From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 99C9D4CA26E; Tue, 12 May 2026 12:12:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587951; cv=none; b=D4rPQ5PSrgYwU5G8bnC3qMHRfg/YPYtNu3Bd/CbnEycBRVRJlkDzXJoRtedah2KP31WMXTeGi0OiUsImZVR9IfyYG4lJvAsTe5qNA3I4i7bkFKluiCMayQ+weg3NtmDzFRaZsBwy2vMojOGqREOOv/PJWvv3J73UzYUA/YEKPCY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587951; c=relaxed/simple; bh=AcuMBWGxKM+Z1SUVj3sxCy77yb/cSX8ht4tQTqkYlmY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=psTw+iIJCiawMLoB1po1cFGTKBxh7bNvPZZHV2Zfx2jWpQhrnbqqteBA14Pah9HtIyGsb356IdhmI+4MgxElACho4WY8zRrcBttRN0leOrHbzR2hteOsYjl+S+QnJ3BdthOkGGsX1mhFhuK4rLdAfTT516vHhMkGrBd5HD4rqU8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id F19C2C2BCB0; Tue, 12 May 2026 12:12:26 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea , stable@vger.kernel.org Subject: [PATCH v5 01/17] dmaengine: sh: rz-dmac: Move interrupt request after everything is set up Date: Tue, 12 May 2026 15:12:02 +0300 Message-ID: <20260512121219.216159-2-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Once the interrupt is requested, the interrupt handler may run immediately. Since the IRQ handler can access channel->ch_base, which is initialized only after requesting the IRQ, this may lead to invalid memory access. Likewise, the IRQ thread may access uninitialized data (the ld_free, ld_queue, and ld_active lists), which may also lead to issues. Request the interrupts only after everything is set up. To keep the error path simpler, use dmam_alloc_coherent() instead of dma_alloc_coherent(). Fixes: 5000d37042a6 ("dmaengine: sh: Add DMAC driver for RZ/G2L SoC") Cc: stable@vger.kernel.org Signed-off-by: Claudiu Beznea Reviewed-by: Frank Li --- Changes in v5: - none Changes in v4: - none, this patch is new drivers/dma/sh/rz-dmac.c | 88 +++++++++++++++------------------------- 1 file changed, 33 insertions(+), 55 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 625ff29024de..9f206a33dcc6 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -981,25 +981,6 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, channel->index =3D index; channel->mid_rid =3D -EINVAL; =20 - /* Request the channel interrupt. */ - scnprintf(pdev_irqname, sizeof(pdev_irqname), "ch%u", index); - irq =3D platform_get_irq_byname(pdev, pdev_irqname); - if (irq < 0) - return irq; - - irqname =3D devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u", - dev_name(dmac->dev), index); - if (!irqname) - return -ENOMEM; - - ret =3D devm_request_threaded_irq(dmac->dev, irq, rz_dmac_irq_handler, - rz_dmac_irq_handler_thread, 0, - irqname, channel); - if (ret) { - dev_err(dmac->dev, "failed to request IRQ %u (%d)\n", irq, ret); - return ret; - } - /* Set io base address for each channel */ if (index < 8) { channel->ch_base =3D dmac->base + CHANNEL_0_7_OFFSET + @@ -1012,9 +993,9 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, } =20 /* Allocate descriptors */ - lmdesc =3D dma_alloc_coherent(&pdev->dev, - sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, - &channel->lmdesc.base_dma, GFP_KERNEL); + lmdesc =3D dmam_alloc_coherent(&pdev->dev, + sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, + &channel->lmdesc.base_dma, GFP_KERNEL); if (!lmdesc) { dev_err(&pdev->dev, "Can't allocate memory (lmdesc)\n"); return -ENOMEM; @@ -1030,7 +1011,24 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, INIT_LIST_HEAD(&channel->ld_free); INIT_LIST_HEAD(&channel->ld_active); =20 - return 0; + /* Request the channel interrupt. */ + scnprintf(pdev_irqname, sizeof(pdev_irqname), "ch%u", index); + irq =3D platform_get_irq_byname(pdev, pdev_irqname); + if (irq < 0) + return irq; + + irqname =3D devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u", + dev_name(dmac->dev), index); + if (!irqname) + return -ENOMEM; + + ret =3D devm_request_threaded_irq(dmac->dev, irq, rz_dmac_irq_handler, + rz_dmac_irq_handler_thread, 0, + irqname, channel); + if (ret) + dev_err(dmac->dev, "failed to request IRQ %u (%d)\n", irq, ret); + + return ret; } =20 static void rz_dmac_put_device(void *_dev) @@ -1099,7 +1097,6 @@ static int rz_dmac_probe(struct platform_device *pdev) const char *irqname =3D "error"; struct dma_device *engine; struct rz_dmac *dmac; - int channel_num; int ret; int irq; u8 i; @@ -1132,18 +1129,6 @@ static int rz_dmac_probe(struct platform_device *pde= v) return PTR_ERR(dmac->ext_base); } =20 - /* Register interrupt handler for error */ - irq =3D platform_get_irq_byname_optional(pdev, irqname); - if (irq > 0) { - ret =3D devm_request_irq(&pdev->dev, irq, rz_dmac_irq_handler, 0, - irqname, NULL); - if (ret) { - dev_err(&pdev->dev, "failed to request IRQ %u (%d)\n", - irq, ret); - return ret; - } - } - /* Initialize the channels. */ INIT_LIST_HEAD(&dmac->engine.channels); =20 @@ -1169,6 +1154,18 @@ static int rz_dmac_probe(struct platform_device *pde= v) goto err; } =20 + /* Register interrupt handler for error */ + irq =3D platform_get_irq_byname_optional(pdev, irqname); + if (irq > 0) { + ret =3D devm_request_irq(&pdev->dev, irq, rz_dmac_irq_handler, 0, + irqname, NULL); + if (ret) { + dev_err(&pdev->dev, "failed to request IRQ %u (%d)\n", + irq, ret); + goto err; + } + } + /* Register the DMAC as a DMA provider for DT. */ ret =3D of_dma_controller_register(pdev->dev.of_node, rz_dmac_of_xlate, NULL); @@ -1210,16 +1207,6 @@ static int rz_dmac_probe(struct platform_device *pde= v) dma_register_err: of_dma_controller_free(pdev->dev.of_node); err: - channel_num =3D i ? i - 1 : 0; - for (i =3D 0; i < channel_num; i++) { - struct rz_dmac_chan *channel =3D &dmac->channels[i]; - - dma_free_coherent(&pdev->dev, - sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, - channel->lmdesc.base, - channel->lmdesc.base_dma); - } - reset_control_assert(dmac->rstc); err_pm_runtime_put: pm_runtime_put(&pdev->dev); @@ -1232,18 +1219,9 @@ static int rz_dmac_probe(struct platform_device *pde= v) static void rz_dmac_remove(struct platform_device *pdev) { struct rz_dmac *dmac =3D platform_get_drvdata(pdev); - unsigned int i; =20 dma_async_device_unregister(&dmac->engine); of_dma_controller_free(pdev->dev.of_node); - for (i =3D 0; i < dmac->n_channels; i++) { - struct rz_dmac_chan *channel =3D &dmac->channels[i]; - - dma_free_coherent(&pdev->dev, - sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, - channel->lmdesc.base, - channel->lmdesc.base_dma); - } reset_control_assert(dmac->rstc); pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev); --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8EC0E4C957B; Tue, 12 May 2026 12:12:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587956; cv=none; b=j6J7j26/uBugpIHTlcgTyB1yU3MvCJ/DM6lt0xTssOuTyIWdqCp+tR30/qGXioRM3NdpmrO49FAV8IW8X5a/K/ymJLLTWdv5dEpEebKkoA/YtHUrma2dpLNbsGPj2Kd5wZ5Pf4g4JIQS9lfDbt9XRs0deUGH9x18rQiM+7Y0qiU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587956; c=relaxed/simple; bh=NGeh6VbMXJbRCOaAXOFaMvZWqB1dLolk0xEwA2DIvqM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G+PeI6mPkICOYxbaZt/yrZcCTk073w7wmK0gEI2AQKo5Wh3gD73UpFa2KoV+KijT4OCfU4/3HUj6srib7DEVvABOQ1r2sf2OKsN3zRLKWPmAJMlGB45GzOP1tYNIBvSe/sVUSIOJxinNxF7NCIhMTvNJp8Xddn6ViTz6pFKIMQg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA7EEC2BCB0; Tue, 12 May 2026 12:12:31 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea , stable@vger.kernel.org Subject: [PATCH v5 02/17] dmaengine: sh: rz-dmac: Fix incorrect NULL check on list_first_entry() Date: Tue, 12 May 2026 15:12:03 +0300 Message-ID: <20260512121219.216159-3-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The list passed as argument to list_first_entry() is expected to be not empty. Use list_first_entry_or_null() to avoid dereferencing invalid memory. Fixes: 21323b118c16 ("dmaengine: sh: rz-dmac: Add device_tx_status() callba= ck") Cc: stable@vger.kernel.org Signed-off-by: Claudiu Beznea --- Changes in v5: - none Changes in v4: - none, this patch is new drivers/dma/sh/rz-dmac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 9f206a33dcc6..6d80cb668957 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -723,8 +723,8 @@ static u32 rz_dmac_chan_get_residue(struct rz_dmac_chan= *channel, u32 crla, crtb, i; =20 /* Get current processing virtual descriptor */ - current_desc =3D list_first_entry(&channel->ld_active, - struct rz_dmac_desc, node); + current_desc =3D list_first_entry_or_null(&channel->ld_active, + struct rz_dmac_desc, node); if (!current_desc) return 0; =20 --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 49FFE4C77DD; Tue, 12 May 2026 12:12:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587961; cv=none; b=QkUFBZjdVPgCKURalKrBf6uQ4ewcRjDONSUSb5RW5+frwUGwuPAGjISfGWnkGdhxfLq+kCLGxkJpkfNiD1VyX4JsCzwEQXkIvZVj5JggIs2hTFekafplYMB9CdkZxJ8rdtxP78e+J+jXgA3PqHetG1NgIrH5asZY/INyhABXGhc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587961; c=relaxed/simple; bh=K0OX8V9yxkNRCnZ6OMdT1vA5+id18o/Lx8X7w/dOPNY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YYUemDJGQO5OhinjfFkOadUEsnyTyFtVrQwGGJOkg47/RCDH1MpziYr6+vILr4G2QZSbptwXJ0WfWGDUNrdAkPHTQCnnnP+HeP2s1qMr5gACFuTh7oDk1olixL5pf4WDIOiQVCYqZw02qkYr7BePczATWolf9zPGJGN8QGWLkR8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id A9584C2BCB0; Tue, 12 May 2026 12:12:36 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 03/17] dmaengine: sh: rz-dmac: Use list_first_entry_or_null() Date: Tue, 12 May 2026 15:12:04 +0300 Message-ID: <20260512121219.216159-4-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Use list_first_entry_or_null() instead of open-coding it with a list_empty() check and list_first_entry(). This simplifies the code. Signed-off-by: Claudiu Beznea Reviewed-by: Frank Li --- Changes in v5: - none Changes in v4: - none Changes in v3: - none, this patch is new drivers/dma/sh/rz-dmac.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 6d80cb668957..1717b407ab9e 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -503,11 +503,10 @@ rz_dmac_prep_dma_memcpy(struct dma_chan *chan, dma_ad= dr_t dest, dma_addr_t src, __func__, channel->index, &src, &dest, len); =20 scoped_guard(spinlock_irqsave, &channel->vc.lock) { - if (list_empty(&channel->ld_free)) + desc =3D list_first_entry_or_null(&channel->ld_free, struct rz_dmac_desc= , node); + if (!desc) return NULL; =20 - desc =3D list_first_entry(&channel->ld_free, struct rz_dmac_desc, node); - desc->type =3D RZ_DMAC_DESC_MEMCPY; desc->src =3D src; desc->dest =3D dest; @@ -533,11 +532,10 @@ rz_dmac_prep_slave_sg(struct dma_chan *chan, struct s= catterlist *sgl, int i =3D 0; =20 scoped_guard(spinlock_irqsave, &channel->vc.lock) { - if (list_empty(&channel->ld_free)) + desc =3D list_first_entry_or_null(&channel->ld_free, struct rz_dmac_desc= , node); + if (!desc) return NULL; =20 - desc =3D list_first_entry(&channel->ld_free, struct rz_dmac_desc, node); - for_each_sg(sgl, sg, sg_len, i) dma_length +=3D sg_dma_len(sg); =20 --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D0F084C900F; Tue, 12 May 2026 12:12:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587965; cv=none; b=nHE0xfAA0sglohbNCVQquvUXbYm6+tTqMbJcsTBIMZHfNAxwQeFoyTPQMtw7LOfIloM0Y4uQn/tH2ljw3+U2hjaXbcsfQp69+0DyoSzy7C3BG+L6BmRCmBur95RfATYvrOXT96/SHqWoHbx8a+PZhoi1uMHpoDt58MMpLahavzQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587965; c=relaxed/simple; bh=YcNUW7z3TMPf4u5I451KlVvNO7PLtoJobPjSqeogKYc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OTRVqGY36wxuRRxSH40SZJjnWsDaQPRCLE7ZqeYgNktY/hkAGXG/aaLHV4KQH2ziqkQ2n+aolbFRGrbBbFXgacom4bawSWRyJUBwH8HEacaQHsCNhnA6Kmo90gJxiXrXGBMM6nyWXg894UsNXCJ3Qvum7eeIP6L8Z2bhGNS1IcM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FF2AC2BCF5; Tue, 12 May 2026 12:12:41 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 04/17] dmaengine: sh: rz-dmac: Use rz_dmac_disable_hw() Date: Tue, 12 May 2026 15:12:05 +0300 Message-ID: <20260512121219.216159-5-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Use rz_dmac_disable_hw() instead of open codding it. This unifies the code and prepares it for the addition of suspend to RAM and cyclic DMA. The rz_dmac_disable_hw() from rz_dmac_chan_probe() was moved after vchan_init() as it initializes the channel->vc.chan.device used in rz_dmac_disable_hw(). Signed-off-by: Claudiu Beznea Reviewed-by: Frank Li --- Changes in v5: - none Changes in v4: - in rz_dmac_chan_probe(): moved rz_dmac_disable_hw() after the vchan_init(&channel->vc, &dmac->engine) call as this is the one which initializes data structures used by the debug code from rz_dmac_disable_hw(); updated the patch description to reflect this =20 Changes in v3: - none, this patch is new drivers/dma/sh/rz-dmac.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 1717b407ab9e..40ddf534c094 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -873,7 +873,7 @@ static void rz_dmac_irq_handle_channel(struct rz_dmac_c= han *channel) channel->index, chstat); =20 scoped_guard(spinlock_irqsave, &channel->vc.lock) - rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); + rz_dmac_disable_hw(channel); return; } =20 @@ -1000,15 +1000,15 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, } rz_lmdesc_setup(channel, lmdesc); =20 - /* Initialize register for each channel */ - rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); - channel->vc.desc_free =3D rz_dmac_virt_desc_free; vchan_init(&channel->vc, &dmac->engine); INIT_LIST_HEAD(&channel->ld_queue); INIT_LIST_HEAD(&channel->ld_free); INIT_LIST_HEAD(&channel->ld_active); =20 + /* Initialize register for each channel */ + rz_dmac_disable_hw(channel); + /* Request the channel interrupt. */ scnprintf(pdev_irqname, sizeof(pdev_irqname), "ch%u", index); irq =3D platform_get_irq_byname(pdev, pdev_irqname); --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 87F4E3859D2; Tue, 12 May 2026 12:12:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587970; cv=none; b=qHU529FLjx8zJVloSVOgaJepXzEg1v7ehS71PwpdjaR7sKx7AsMjJuJQMLZpX5fxB4GPlCuKU4x3eNeFcw1Ys1n6WOc7tVj/atwNnEIUOhN1cxTCZB1lQigNFsV1b3w1p5W7lshc3t59jKusph+Y6eOwtNGjM/s04tTEpMhA0+g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587970; c=relaxed/simple; bh=wCRVG1+Al3r6VktOLGZhtmmbhoSh6FU64fB0b55xhgg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=b6KXVxGK70xGxl+qzmh1A4SpL59RaWNLLo/L545o9cq5mt/2X51vlbZUtXYrOoce2QnYCkYtfevWNTAB5jKoaORnrwUciNrV0q0QfL89Uv1CPuHYT1x8BLm5LrUWnKnuo1TYqN6TEr6+fbLB/9oqsem0Ji0XDqPtm/KtbIDKGqY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id F00C8C2BCB0; Tue, 12 May 2026 12:12:45 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 05/17] dmaengine: sh: rz-dmac: Add helper to compute the lmdesc address Date: Tue, 12 May 2026 15:12:06 +0300 Message-ID: <20260512121219.216159-6-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a helper function to compute the lmdesc address. This makes the code easier to understand, and the helper will be used in subsequent patches. Signed-off-by: Claudiu Beznea Reviewed-by: Frank Li --- Changes in v5: - none Changes in v4: - none Changes in v3: - none, this patch is new drivers/dma/sh/rz-dmac.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 40ddf534c094..c48858b68dee 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -259,6 +259,12 @@ static void rz_lmdesc_setup(struct rz_dmac_chan *chann= el, * Descriptors preparation */ =20 +static u32 rz_dmac_lmdesc_addr(struct rz_dmac_chan *channel, struct rz_lmd= esc *lmdesc) +{ + return channel->lmdesc.base_dma + + (sizeof(struct rz_lmdesc) * (lmdesc - channel->lmdesc.base)); +} + static void rz_dmac_lmdesc_recycle(struct rz_dmac_chan *channel) { struct rz_lmdesc *lmdesc =3D channel->lmdesc.head; @@ -284,9 +290,7 @@ static void rz_dmac_enable_hw(struct rz_dmac_chan *chan= nel) =20 rz_dmac_lmdesc_recycle(channel); =20 - nxla =3D channel->lmdesc.base_dma + - (sizeof(struct rz_lmdesc) * (channel->lmdesc.head - - channel->lmdesc.base)); + nxla =3D rz_dmac_lmdesc_addr(channel, channel->lmdesc.head); =20 chstat =3D rz_dmac_ch_readl(channel, CHSTAT, 1); if (!(chstat & CHSTAT_EN)) { --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3A06A3859D2; Tue, 12 May 2026 12:12:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587975; cv=none; b=Ks3KoJDtSAW44Uty6qeq8UqMgw1HbcfoPBtfnrqnS9Q0QMc8Hz0eAhVhYgLM6CPJD6/IjPMXI6X+4KVrxkpg12tfyxWaIkOwYuqT/wHClWKX13fkcqn8bY/S96n7vBTp5G5Tepxm0J9yPgIF370WYMGFHewPJLCqMQa0KUavx8s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587975; c=relaxed/simple; bh=qQ19DrfnIDdGoT2grVOqiAVtiTPY/GxqXYQrs+yywPg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sL3ilELfwmjOHg6LeZ2mqEI9xxL977KNog2zCxh7qpJxS+XBtOrXeAUp5xSt246j6+u+XOiGRACAp4kvSgpjmibin1V98TZB8r5opp0hYXAKuw+ScjiqPTulqalKZZcAjoiryyuHMV3cuNTDrpgOkG/4eNXBonaOJX/ONhuSbNY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A819C2BCF5; Tue, 12 May 2026 12:12:50 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 06/17] dmaengine: sh: rz-dmac: Save the start LM descriptor Date: Tue, 12 May 2026 15:12:07 +0300 Message-ID: <20260512121219.216159-7-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Save the start LM descriptor to avoid looping through the entire channel's LM descriptor list when computing the residue. This avoids unnecessary iterations. Signed-off-by: Claudiu Beznea --- Changes in v5: - none Changes in v4: - none Changes in v3: - none, this patch is new drivers/dma/sh/rz-dmac.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index c48858b68dee..d3926ecd63ac 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -58,6 +58,7 @@ struct rz_dmac_desc { /* For slave sg */ struct scatterlist *sg; unsigned int sgcount; + struct rz_lmdesc *start_lmdesc; }; =20 #define to_rz_dmac_desc(d) container_of(d, struct rz_dmac_desc, vd) @@ -343,6 +344,8 @@ static void rz_dmac_prepare_desc_for_memcpy(struct rz_d= mac_chan *channel) struct rz_dmac_desc *d =3D channel->desc; u32 chcfg =3D CHCFG_MEM_COPY; =20 + d->start_lmdesc =3D lmdesc; + /* prepare descriptor */ lmdesc->sa =3D d->src; lmdesc->da =3D d->dest; @@ -377,6 +380,7 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct r= z_dmac_chan *channel) } =20 lmdesc =3D channel->lmdesc.tail; + d->start_lmdesc =3D lmdesc; =20 for (i =3D 0, sg =3D sgl; i < sg_len; i++, sg =3D sg_next(sg)) { if (d->direction =3D=3D DMA_DEV_TO_MEM) { @@ -693,9 +697,10 @@ rz_dmac_get_next_lmdesc(struct rz_lmdesc *base, struct= rz_lmdesc *lmdesc) return next; } =20 -static u32 rz_dmac_calculate_residue_bytes_in_vd(struct rz_dmac_chan *chan= nel, u32 crla) +static u32 rz_dmac_calculate_residue_bytes_in_vd(struct rz_dmac_chan *chan= nel, + struct rz_dmac_desc *desc, u32 crla) { - struct rz_lmdesc *lmdesc =3D channel->lmdesc.head; + struct rz_lmdesc *lmdesc =3D desc->start_lmdesc; struct dma_chan *chan =3D &channel->vc.chan; struct rz_dmac *dmac =3D to_rz_dmac(chan->device); u32 residue =3D 0, i =3D 0; @@ -794,7 +799,7 @@ static u32 rz_dmac_chan_get_residue(struct rz_dmac_chan= *channel, * Calculate number of bytes transferred in processing virtual descriptor. * One virtual descriptor can have many lmdesc. */ - return crtb + rz_dmac_calculate_residue_bytes_in_vd(channel, crla); + return crtb + rz_dmac_calculate_residue_bytes_in_vd(channel, current_desc= , crla); } =20 static enum dma_status rz_dmac_tx_status(struct dma_chan *chan, --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E2F144C77BE; Tue, 12 May 2026 12:12:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587979; cv=none; b=aZj2Bdg86C18s48T1FFSqq5Dxo8p87XPD4IJ+l0Hvvlprqloo0NwB63Y6XYvp1MhCOz35s6ApyFMVk/KRf9xSqUvzandtRtu4JR4JmcvmSIxWDDYRraJGN3+g7eKxIOTzAbFkgXgmm0Sk8/rcFgBEGZaFKtLwJ11yGaon6p8V1w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587979; c=relaxed/simple; bh=06hy3/fsys1DTWKDjfj3VVtBqDjPHe+h+KVYYXDB3GA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fTj0n7AY3nOWyK8NpXZKPq3VQ0ESfLhRMvT8UW6fo5aNpHrRtgHq+gPwHQqm+9cnSVICV+giD3Zz93G+V9gtWr9YHl7QwF5scECNKlEHl1S1Zsb4cjDgkw/hD0JFTAHes51dOXRuIHOuEkTUtS780IJXNTlOgUBaQl2fGKTNQbI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59E45C2BCB0; Tue, 12 May 2026 12:12:55 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 07/17] dmaengine: sh: rz-dmac: Add helper to check if the channel is enabled Date: Tue, 12 May 2026 15:12:08 +0300 Message-ID: <20260512121219.216159-8-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a helper to check if the channel is enabled. This will be reused in subsequent patches. Signed-off-by: Claudiu Beznea Reviewed-by: Frank Li --- Changes in v5: - none Changes in v4: - none Changes in v3: - none, this patch is new drivers/dma/sh/rz-dmac.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index d3926ecd63ac..c7337cf27136 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -279,6 +279,13 @@ static void rz_dmac_lmdesc_recycle(struct rz_dmac_chan= *channel) channel->lmdesc.head =3D lmdesc; } =20 +static bool rz_dmac_chan_is_enabled(struct rz_dmac_chan *chan) +{ + u32 val =3D rz_dmac_ch_readl(chan, CHSTAT, 1); + + return !!(val & CHSTAT_EN); +} + static void rz_dmac_enable_hw(struct rz_dmac_chan *channel) { struct dma_chan *chan =3D &channel->vc.chan; @@ -840,8 +847,7 @@ static int rz_dmac_device_pause(struct dma_chan *chan) =20 guard(spinlock_irqsave)(&channel->vc.lock); =20 - val =3D rz_dmac_ch_readl(channel, CHSTAT, 1); - if (!(val & CHSTAT_EN)) + if (!rz_dmac_chan_is_enabled(channel)) return 0; =20 rz_dmac_ch_writel(channel, CHCTRL_SETSUS, CHCTRL, 1); --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BBECB4D98F6; Tue, 12 May 2026 12:13:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587984; cv=none; b=NRJ/BitlhWEt28cBSVLnGbsfNrDcU+Vl5aA8wjTjHpl+uXSNpwiiVNMMei4XTsDAfzZKsHAphbFUbbP31tF73W/pu18EqHg4tPuIILK7z9c4akka9g1gyP0aZ2Ko7/F8QlEdbB4rHMIAvMfQl8MsGGhZVK32b2ToBdKsIYPBPK0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587984; c=relaxed/simple; bh=X3LJNaLbS05gixSj6TGHk0OFYoT5XuAF7LL7kOAtbdQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IMWyo8WLxK3iIXBH+RRsINblr+iyVc9Qu6u8Yn3MCuvHcJVS5waJSOP8Zj6jVGRXK/bw9zdE/eVJyT3JO8qtef0EtFQydInQeGH2vBAcYKDKHmzNyTkJLhj+MutaAfTgH6IL8Wvn6yMouYUdNn7e4iv507WkSP8K6Ua33m72aiU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 29A6EC2BCB0; Tue, 12 May 2026 12:12:59 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 08/17] dmaengine: sh: rz-dmac: Add helper to check if the channel is paused Date: Tue, 12 May 2026 15:12:09 +0300 Message-ID: <20260512121219.216159-9-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a helper to check if the channel is paused. This will be reused in subsequent patches. Signed-off-by: Claudiu Beznea Reviewed-by: Frank Li --- Changes in v5: - none Changes in v4: - none Changes in v3: - none, this patch is new drivers/dma/sh/rz-dmac.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index c7337cf27136..042f85e58a79 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -286,6 +286,13 @@ static bool rz_dmac_chan_is_enabled(struct rz_dmac_cha= n *chan) return !!(val & CHSTAT_EN); } =20 +static bool rz_dmac_chan_is_paused(struct rz_dmac_chan *chan) +{ + u32 val =3D rz_dmac_ch_readl(chan, CHSTAT, 1); + + return !!(val & CHSTAT_SUS); +} + static void rz_dmac_enable_hw(struct rz_dmac_chan *channel) { struct dma_chan *chan =3D &channel->vc.chan; @@ -822,12 +829,9 @@ static enum dma_status rz_dmac_tx_status(struct dma_ch= an *chan, return status; =20 scoped_guard(spinlock_irqsave, &channel->vc.lock) { - u32 val; - residue =3D rz_dmac_chan_get_residue(channel, cookie); =20 - val =3D rz_dmac_ch_readl(channel, CHSTAT, 1); - if (val & CHSTAT_SUS) + if (rz_dmac_chan_is_paused(channel)) status =3D DMA_PAUSED; } =20 --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9BBA64E378E; Tue, 12 May 2026 12:13:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587989; cv=none; b=DUQKgE4hxjwBnjSJSNuj7ro6gI/A4PGaBnk4wbrNJzwBPJiy15bQBH/1bYtL3SsruvEZGr3V+rGTl0P7RA5PHwj+GZq0QFDp4c8zUChhXZZn68duY2VCvFq6t6n2l/RezLw0kuexNfJQcJtVNSxJfps45kKowgw5YEgBVO0dXyo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587989; c=relaxed/simple; bh=sD54EqZbsJWFBd9zrfXglD3j3zqkgX+TTFtABKNhgV4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KDUGfdVH3LnRUoOol2xi2DdpznxKmCT1B2+clr6Z75wJEAlTFRiXoBbP5QvGzPlL040a22tnP+CZl/nwp2K8ypCqNdYe93FZSY0t2qSsGe+nGqtn32jio6ZBRUb+cEt5icwnDFQIYHZXlR07w/Tsd96nRD7THZosdkSvXxQI3wk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id D08DFC2BCF7; Tue, 12 May 2026 12:13:04 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 09/17] dmaengine: sh: rz-dmac: Use virt-dma APIs for channel descriptor processing Date: Tue, 12 May 2026 15:12:10 +0300 Message-ID: <20260512121219.216159-10-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The driver used a mix of virt-dma APIs and driver specific logic to process descriptors. It maintained three internal queues: ld_free, ld_queue, and ld_active as follows: - ld_free: stores the descriptors pre-allocated at probe time - ld_queue: stores descriptors after they are taken from ld_free and prepared. At the same time, vchan_tx_prep() queues them to vc->desc_allocated. The vc->desc_allocated list is then checked in rz_dmac_issue_pending() and rz_dmac_irq_handler_thread() before starting a new transfer via rz_dmac_xfer_desc(). In turn, rz_dmac_xfer_desc() grabs the next descriptor from vc->desc_issued and submits it for transfer - ld_active: stores the descriptors currently being transferred The interrupt handler moved a completed descriptor to ld_free before invoking its completion callback. Once returned to ld_free, the descriptor can be reused to prepare a new transfer. In theory, this means the descriptor could be re-prepared before its completion callback is called. Commit fully back the driver by the virt-dma APIs. With this, only ld_free need to be kept to track how many free descriptors are available. This is now done as follows: - the prepare stage removes the first descriptor from the ld_free and prepares it - the completion calls for it vc->desc_free() (rz_dmac_virt_desc_free()) which re-adds the descriptor at the end of ld_free With this, the critical areas in prepare callbacks were minimized to only getting the descriptor from the ld_free list. This change introduces struct rz_dmac_chan::desc to keep track of the currently transferred descriptor. It is cleared in rz_dmac_terminate_all(), referenced from rz_dmac_issue_pending() to determine whether a new transfer can be started, and from rz_dmac_irq_handler_thread() once a descriptor has completed. Finally, the rz_dmac_device_synchronize() was updated with vchan_synchronize() call to ensure the terminated descriptor is freed and the tasklet is killed. With this, residue computation is also simplified, as it can now be handled entirely through the virt-dma APIs. The spin_lock/unlock operations from rz_dmac_irq_handler_thread() were replaced by guard as the final code after rework is simpler this way. As subsequent commits will set the Link End bit on the last descriptor of a transfer, rz_dmac_enable_hw() is also adjusted as part of the full conversion to virt-dma APIs. It no longer checks the channel enable status itself; instead, its callers verify whether the channel is enabled and whether the previous transfer has completed before starting a new one. Signed-off-by: Claudiu Beznea --- Changes in v5: - none Changes in v4: - in rz_dmac_tx_status(): return DMA_PAUSED if the channel is paused; call rz_dmac_chan_get_residue() only if status is not complete Changes in v3: - none, this patch is new drivers/dma/sh/rz-dmac.c | 233 +++++++++++++++------------------------ 1 file changed, 86 insertions(+), 147 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 042f85e58a79..53ee9fe65261 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -79,8 +79,6 @@ struct rz_dmac_chan { int mid_rid; =20 struct list_head ld_free; - struct list_head ld_queue; - struct list_head ld_active; =20 struct { struct rz_lmdesc *base; @@ -299,7 +297,6 @@ static void rz_dmac_enable_hw(struct rz_dmac_chan *chan= nel) struct rz_dmac *dmac =3D to_rz_dmac(chan->device); u32 nxla; u32 chctrl; - u32 chstat; =20 dev_dbg(dmac->dev, "%s channel %d\n", __func__, channel->index); =20 @@ -307,14 +304,11 @@ static void rz_dmac_enable_hw(struct rz_dmac_chan *ch= annel) =20 nxla =3D rz_dmac_lmdesc_addr(channel, channel->lmdesc.head); =20 - chstat =3D rz_dmac_ch_readl(channel, CHSTAT, 1); - if (!(chstat & CHSTAT_EN)) { - chctrl =3D (channel->chctrl | CHCTRL_SETEN); - rz_dmac_ch_writel(channel, nxla, NXLA, 1); - rz_dmac_ch_writel(channel, channel->chcfg, CHCFG, 1); - rz_dmac_ch_writel(channel, CHCTRL_SWRST, CHCTRL, 1); - rz_dmac_ch_writel(channel, chctrl, CHCTRL, 1); - } + chctrl =3D (channel->chctrl | CHCTRL_SETEN); + rz_dmac_ch_writel(channel, nxla, NXLA, 1); + rz_dmac_ch_writel(channel, channel->chcfg, CHCFG, 1); + rz_dmac_ch_writel(channel, CHCTRL_SWRST, CHCTRL, 1); + rz_dmac_ch_writel(channel, chctrl, CHCTRL, 1); } =20 static void rz_dmac_disable_hw(struct rz_dmac_chan *channel) @@ -426,18 +420,20 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct= rz_dmac_chan *channel) channel->chctrl =3D CHCTRL_SETEN; } =20 -static int rz_dmac_xfer_desc(struct rz_dmac_chan *chan) +static void rz_dmac_xfer_desc(struct rz_dmac_chan *chan) { - struct rz_dmac_desc *d =3D chan->desc; struct virt_dma_desc *vd; =20 vd =3D vchan_next_desc(&chan->vc); - if (!vd) - return 0; + if (!vd) { + chan->desc =3D NULL; + return; + } =20 list_del(&vd->node); + chan->desc =3D to_rz_dmac_desc(vd); =20 - switch (d->type) { + switch (chan->desc->type) { case RZ_DMAC_DESC_MEMCPY: rz_dmac_prepare_desc_for_memcpy(chan); break; @@ -445,14 +441,9 @@ static int rz_dmac_xfer_desc(struct rz_dmac_chan *chan) case RZ_DMAC_DESC_SLAVE_SG: rz_dmac_prepare_descs_for_slave_sg(chan); break; - - default: - return -EINVAL; } =20 rz_dmac_enable_hw(chan); - - return 0; } =20 /* @@ -494,8 +485,6 @@ static void rz_dmac_free_chan_resources(struct dma_chan= *chan) rz_lmdesc_setup(channel, channel->lmdesc.base); =20 rz_dmac_disable_hw(channel); - list_splice_tail_init(&channel->ld_active, &channel->ld_free); - list_splice_tail_init(&channel->ld_queue, &channel->ld_free); =20 if (channel->mid_rid >=3D 0) { clear_bit(channel->mid_rid, dmac->modules); @@ -504,13 +493,19 @@ static void rz_dmac_free_chan_resources(struct dma_ch= an *chan) =20 spin_unlock_irqrestore(&channel->vc.lock, flags); =20 + vchan_free_chan_resources(&channel->vc); + + spin_lock_irqsave(&channel->vc.lock, flags); + list_for_each_entry_safe(desc, _desc, &channel->ld_free, node) { + list_del(&desc->node); kfree(desc); channel->descs_allocated--; } =20 INIT_LIST_HEAD(&channel->ld_free); - vchan_free_chan_resources(&channel->vc); + + spin_unlock_irqrestore(&channel->vc.lock, flags); } =20 static struct dma_async_tx_descriptor * @@ -529,15 +524,15 @@ rz_dmac_prep_dma_memcpy(struct dma_chan *chan, dma_ad= dr_t dest, dma_addr_t src, if (!desc) return NULL; =20 - desc->type =3D RZ_DMAC_DESC_MEMCPY; - desc->src =3D src; - desc->dest =3D dest; - desc->len =3D len; - desc->direction =3D DMA_MEM_TO_MEM; - - list_move_tail(channel->ld_free.next, &channel->ld_queue); + list_del(&desc->node); } =20 + desc->type =3D RZ_DMAC_DESC_MEMCPY; + desc->src =3D src; + desc->dest =3D dest; + desc->len =3D len; + desc->direction =3D DMA_MEM_TO_MEM; + return vchan_tx_prep(&channel->vc, &desc->vd, flags); } =20 @@ -558,22 +553,22 @@ rz_dmac_prep_slave_sg(struct dma_chan *chan, struct s= catterlist *sgl, if (!desc) return NULL; =20 - for_each_sg(sgl, sg, sg_len, i) - dma_length +=3D sg_dma_len(sg); + list_del(&desc->node); + } =20 - desc->type =3D RZ_DMAC_DESC_SLAVE_SG; - desc->sg =3D sgl; - desc->sgcount =3D sg_len; - desc->len =3D dma_length; - desc->direction =3D direction; + for_each_sg(sgl, sg, sg_len, i) + dma_length +=3D sg_dma_len(sg); =20 - if (direction =3D=3D DMA_DEV_TO_MEM) - desc->src =3D channel->src_per_address; - else - desc->dest =3D channel->dst_per_address; + desc->type =3D RZ_DMAC_DESC_SLAVE_SG; + desc->sg =3D sgl; + desc->sgcount =3D sg_len; + desc->len =3D dma_length; + desc->direction =3D direction; =20 - list_move_tail(channel->ld_free.next, &channel->ld_queue); - } + if (direction =3D=3D DMA_DEV_TO_MEM) + desc->src =3D channel->src_per_address; + else + desc->dest =3D channel->dst_per_address; =20 return vchan_tx_prep(&channel->vc, &desc->vd, flags); } @@ -588,8 +583,11 @@ static int rz_dmac_terminate_all(struct dma_chan *chan) rz_dmac_disable_hw(channel); rz_lmdesc_setup(channel, channel->lmdesc.base); =20 - list_splice_tail_init(&channel->ld_active, &channel->ld_free); - list_splice_tail_init(&channel->ld_queue, &channel->ld_free); + if (channel->desc) { + vchan_terminate_vdesc(&channel->desc->vd); + channel->desc =3D NULL; + } + vchan_get_all_descriptors(&channel->vc, &head); spin_unlock_irqrestore(&channel->vc.lock, flags); vchan_dma_desc_free_list(&channel->vc, &head); @@ -600,25 +598,16 @@ static int rz_dmac_terminate_all(struct dma_chan *cha= n) static void rz_dmac_issue_pending(struct dma_chan *chan) { struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); - struct rz_dmac *dmac =3D to_rz_dmac(chan->device); - struct rz_dmac_desc *desc; unsigned long flags; =20 spin_lock_irqsave(&channel->vc.lock, flags); =20 - if (!list_empty(&channel->ld_queue)) { - desc =3D list_first_entry(&channel->ld_queue, - struct rz_dmac_desc, node); - channel->desc =3D desc; - if (vchan_issue_pending(&channel->vc)) { - if (rz_dmac_xfer_desc(channel) < 0) - dev_warn(dmac->dev, "ch: %d couldn't issue DMA xfer\n", - channel->index); - else - list_move_tail(channel->ld_queue.next, - &channel->ld_active); - } - } + /* + * Issue the descriptor. If another transfer is already in progress, the + * issued descriptor will be handled after the current transfer finishes. + */ + if (vchan_issue_pending(&channel->vc) && !channel->desc) + rz_dmac_xfer_desc(channel); =20 spin_unlock_irqrestore(&channel->vc.lock, flags); } @@ -676,13 +665,13 @@ static int rz_dmac_config(struct dma_chan *chan, =20 static void rz_dmac_virt_desc_free(struct virt_dma_desc *vd) { - /* - * Place holder - * Descriptor allocation is done during alloc_chan_resources and - * get freed during free_chan_resources. - * list is used to manage the descriptors and avoid any memory - * allocation/free during DMA read/write. - */ + struct rz_dmac_chan *channel =3D to_rz_dmac_chan(vd->tx.chan); + struct virt_dma_chan *vc =3D to_virt_chan(vd->tx.chan); + struct rz_dmac_desc *desc =3D to_rz_dmac_desc(vd); + + guard(spinlock_irqsave)(&vc->lock); + + list_add_tail(&desc->node, &channel->ld_free); } =20 static void rz_dmac_device_synchronize(struct dma_chan *chan) @@ -692,6 +681,8 @@ static void rz_dmac_device_synchronize(struct dma_chan = *chan) u32 chstat; int ret; =20 + vchan_synchronize(&channel->vc); + ret =3D read_poll_timeout(rz_dmac_ch_readl, chstat, !(chstat & CHSTAT_EN), 100, 100000, false, channel, CHSTAT, 1); if (ret < 0) @@ -739,58 +730,22 @@ static u32 rz_dmac_calculate_residue_bytes_in_vd(stru= ct rz_dmac_chan *channel, static u32 rz_dmac_chan_get_residue(struct rz_dmac_chan *channel, dma_cookie_t cookie) { - struct rz_dmac_desc *current_desc, *desc; - enum dma_status status; + struct rz_dmac_desc *desc =3D NULL; + struct virt_dma_desc *vd; u32 crla, crtb, i; =20 - /* Get current processing virtual descriptor */ - current_desc =3D list_first_entry_or_null(&channel->ld_active, - struct rz_dmac_desc, node); - if (!current_desc) - return 0; - - /* - * If the cookie corresponds to a descriptor that has been completed - * there is no residue. The same check has already been performed by the - * caller but without holding the channel lock, so the descriptor could - * now be complete. - */ - status =3D dma_cookie_status(&channel->vc.chan, cookie, NULL); - if (status =3D=3D DMA_COMPLETE) - return 0; - - /* - * If the cookie doesn't correspond to the currently processing virtual - * descriptor then the descriptor hasn't been processed yet, and the - * residue is equal to the full descriptor size. Also, a client driver - * is possible to call this function before rz_dmac_irq_handler_thread() - * runs. In this case, the running descriptor will be the next - * descriptor, and will appear in the done list. So, if the argument - * cookie matches the done list's cookie, we can assume the residue is - * zero. - */ - if (cookie !=3D current_desc->vd.tx.cookie) { - list_for_each_entry(desc, &channel->ld_free, node) { - if (cookie =3D=3D desc->vd.tx.cookie) - return 0; - } - - list_for_each_entry(desc, &channel->ld_queue, node) { - if (cookie =3D=3D desc->vd.tx.cookie) - return desc->len; - } - - list_for_each_entry(desc, &channel->ld_active, node) { - if (cookie =3D=3D desc->vd.tx.cookie) - return desc->len; - } + vd =3D vchan_find_desc(&channel->vc, cookie); + if (vd) { + /* Descriptor has been issued but not yet processed. */ + desc =3D to_rz_dmac_desc(vd); + return desc->len; + } else if (channel->desc && channel->desc->vd.tx.cookie =3D=3D cookie) { + /* Descriptor is currently processed. */ + desc =3D channel->desc; + } =20 - /* - * No descriptor found for the cookie, there's thus no residue. - * This shouldn't happen if the calling driver passes a correct - * cookie value. - */ - WARN(1, "No descriptor for cookie!"); + if (!desc) { + /* Descriptor was not found. May be already completed by now. */ return 0; } =20 @@ -813,7 +768,7 @@ static u32 rz_dmac_chan_get_residue(struct rz_dmac_chan= *channel, * Calculate number of bytes transferred in processing virtual descriptor. * One virtual descriptor can have many lmdesc. */ - return crtb + rz_dmac_calculate_residue_bytes_in_vd(channel, current_desc= , crla); + return crtb + rz_dmac_calculate_residue_bytes_in_vd(channel, desc, crla); } =20 static enum dma_status rz_dmac_tx_status(struct dma_chan *chan, @@ -824,21 +779,17 @@ static enum dma_status rz_dmac_tx_status(struct dma_c= han *chan, enum dma_status status; u32 residue; =20 - status =3D dma_cookie_status(chan, cookie, txstate); - if (status =3D=3D DMA_COMPLETE || !txstate) - return status; - scoped_guard(spinlock_irqsave, &channel->vc.lock) { + status =3D dma_cookie_status(chan, cookie, txstate); + if (status =3D=3D DMA_COMPLETE || !txstate) + return status; + residue =3D rz_dmac_chan_get_residue(channel, cookie); =20 - if (rz_dmac_chan_is_paused(channel)) + if (status =3D=3D DMA_IN_PROGRESS && rz_dmac_chan_is_paused(channel)) status =3D DMA_PAUSED; } =20 - /* if there's no residue and no paused, the cookie is complete */ - if (!residue && status !=3D DMA_PAUSED) - return DMA_COMPLETE; - dma_set_residue(txstate, residue); =20 return status; @@ -918,28 +869,18 @@ static irqreturn_t rz_dmac_irq_handler(int irq, void = *dev_id) static irqreturn_t rz_dmac_irq_handler_thread(int irq, void *dev_id) { struct rz_dmac_chan *channel =3D dev_id; - struct rz_dmac_desc *desc =3D NULL; - unsigned long flags; + struct rz_dmac_desc *desc; =20 - spin_lock_irqsave(&channel->vc.lock, flags); + guard(spinlock_irqsave)(&channel->vc.lock); =20 - if (list_empty(&channel->ld_active)) { - /* Someone might have called terminate all */ - goto out; - } + desc =3D channel->desc; + if (!desc) + return IRQ_HANDLED; =20 - desc =3D list_first_entry(&channel->ld_active, struct rz_dmac_desc, node); vchan_cookie_complete(&desc->vd); - list_move_tail(channel->ld_active.next, &channel->ld_free); - if (!list_empty(&channel->ld_queue)) { - desc =3D list_first_entry(&channel->ld_queue, struct rz_dmac_desc, - node); - channel->desc =3D desc; - if (rz_dmac_xfer_desc(channel) =3D=3D 0) - list_move_tail(channel->ld_queue.next, &channel->ld_active); - } -out: - spin_unlock_irqrestore(&channel->vc.lock, flags); + channel->desc =3D NULL; + + rz_dmac_xfer_desc(channel); =20 return IRQ_HANDLED; } @@ -1021,9 +962,7 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, =20 channel->vc.desc_free =3D rz_dmac_virt_desc_free; vchan_init(&channel->vc, &dmac->engine); - INIT_LIST_HEAD(&channel->ld_queue); INIT_LIST_HEAD(&channel->ld_free); - INIT_LIST_HEAD(&channel->ld_active); =20 /* Initialize register for each channel */ rz_dmac_disable_hw(channel); --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C9CD44DA54C; Tue, 12 May 2026 12:13:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587993; cv=none; b=niA9Uc11VXi72PiMIOQ0A9Bg784Uk3Cr0njw72GzsefQ3aFvC49f7W3B5ZkC9fvQmabK9JO2rSORwgZeSm9fPYwcbDPnVf2/lO7ZIN7mLR0HsmhEniXNq5Ai7QtmlEb751tTkExGC0BF9z/Bt2fHjVAkKo7XwbT2lwGSD0O2sDc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587993; c=relaxed/simple; bh=9x0vcYPg0jIbWOCHQxnptunZPxreXjlirrb5GA932BQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=P2lTs3wlOQQ29p4EPbW/bH6TJ9uI8rUrMXaqCDt68E0SUmJ+ZJAk9e+cTItTGDKC6AHDY/z+GLqj9ZcA6AqZpTKQFvZhckyFQDtpiFVar9y62AZFz3rtcnMyDlzkJ74cnPZxORH3Z8tawl99SPilePOy6mKwHH3jIMADti65EC4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7460BC2BCB0; Tue, 12 May 2026 12:13:09 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 10/17] dmaengine: sh: rz-dmac: Refactor pause/resume code Date: Tue, 12 May 2026 15:12:11 +0300 Message-ID: <20260512121219.216159-11-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Subsequent patches will add suspend/resume and cyclic DMA support to the rz-dmac driver. This support needs to work on SoCs where power to most components (including DMA) is turned off during system suspend. For this, some channels (for example cyclic ones) may need to be paused and resumed manually by the DMA driver during system suspend/resume. Refactor the pause/resume support so the same code can be reused in the system suspend/resume path. Signed-off-by: Claudiu Beznea --- Changes in v5: - none Changes in v4: - reset channel->status in rz_dmac_free_chan_resources() and rz_dmac_terminate_all() Changes in v3: - none, this patch new new drivers/dma/sh/rz-dmac.c | 73 ++++++++++++++++++++++++++++++++++------ 1 file changed, 62 insertions(+), 11 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 53ee9fe65261..2bf796dcc5f6 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -63,6 +64,14 @@ struct rz_dmac_desc { =20 #define to_rz_dmac_desc(d) container_of(d, struct rz_dmac_desc, vd) =20 +/** + * enum rz_dmac_chan_status: RZ DMAC channel status + * @RZ_DMAC_CHAN_STATUS_PAUSED: Channel is paused though DMA engine callba= cks + */ +enum rz_dmac_chan_status { + RZ_DMAC_CHAN_STATUS_PAUSED, +}; + struct rz_dmac_chan { struct virt_dma_chan vc; void __iomem *ch_base; @@ -74,6 +83,8 @@ struct rz_dmac_chan { dma_addr_t src_per_address; dma_addr_t dst_per_address; =20 + unsigned long status; + u32 chcfg; u32 chctrl; int mid_rid; @@ -491,6 +502,8 @@ static void rz_dmac_free_chan_resources(struct dma_chan= *chan) channel->mid_rid =3D -EINVAL; } =20 + channel->status =3D 0; + spin_unlock_irqrestore(&channel->vc.lock, flags); =20 vchan_free_chan_resources(&channel->vc); @@ -589,6 +602,9 @@ static int rz_dmac_terminate_all(struct dma_chan *chan) } =20 vchan_get_all_descriptors(&channel->vc, &head); + + channel->status =3D 0; + spin_unlock_irqrestore(&channel->vc.lock, flags); vchan_dma_desc_free_list(&channel->vc, &head); =20 @@ -795,35 +811,70 @@ static enum dma_status rz_dmac_tx_status(struct dma_c= han *chan, return status; } =20 -static int rz_dmac_device_pause(struct dma_chan *chan) +static int rz_dmac_device_pause_set(struct rz_dmac_chan *channel, + unsigned long set_bitmask) { - struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); + int ret =3D 0; u32 val; =20 - guard(spinlock_irqsave)(&channel->vc.lock); + lockdep_assert_held(&channel->vc.lock); =20 if (!rz_dmac_chan_is_enabled(channel)) return 0; =20 + if (rz_dmac_chan_is_paused(channel)) + goto set_bit; + rz_dmac_ch_writel(channel, CHCTRL_SETSUS, CHCTRL, 1); - return read_poll_timeout_atomic(rz_dmac_ch_readl, val, - (val & CHSTAT_SUS), 1, 1024, - false, channel, CHSTAT, 1); + ret =3D read_poll_timeout_atomic(rz_dmac_ch_readl, val, + (val & CHSTAT_SUS), 1, 1024, false, + channel, CHSTAT, 1); + +set_bit: + channel->status |=3D set_bitmask; + + return ret; } =20 -static int rz_dmac_device_resume(struct dma_chan *chan) +static int rz_dmac_device_pause(struct dma_chan *chan) { struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); - u32 val; =20 guard(spinlock_irqsave)(&channel->vc.lock); =20 + return rz_dmac_device_pause_set(channel, BIT(RZ_DMAC_CHAN_STATUS_PAUSED)); +} + +static int rz_dmac_device_resume_set(struct rz_dmac_chan *channel, + unsigned long clear_bitmask) +{ + int ret =3D 0; + u32 val; + + lockdep_assert_held(&channel->vc.lock); + /* Do not check CHSTAT_SUS but rely on HW capabilities. */ =20 rz_dmac_ch_writel(channel, CHCTRL_CLRSUS, CHCTRL, 1); - return read_poll_timeout_atomic(rz_dmac_ch_readl, val, - !(val & CHSTAT_SUS), 1, 1024, - false, channel, CHSTAT, 1); + ret =3D read_poll_timeout_atomic(rz_dmac_ch_readl, val, + !(val & CHSTAT_SUS), 1, 1024, false, + channel, CHSTAT, 1); + + channel->status &=3D ~clear_bitmask; + + return ret; +} + +static int rz_dmac_device_resume(struct dma_chan *chan) +{ + struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); + + guard(spinlock_irqsave)(&channel->vc.lock); + + if (!(channel->status & BIT(RZ_DMAC_CHAN_STATUS_PAUSED))) + return 0; + + return rz_dmac_device_resume_set(channel, BIT(RZ_DMAC_CHAN_STATUS_PAUSED)= ); } =20 /* --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 062BA372074; Tue, 12 May 2026 12:13:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587999; cv=none; b=LjGaQA0rCP6PbfSHj/hXSzxXdhdwi4lJ8ufigu5taSZDLek7VbshJHGykFFhtTkDe0TMiIZwV2u5mYKYQQWwIRVyDBEXaI9hAd+JPv8SJljHkx4NoCkfm9pi0TXNWq/GC2L2FCRQH/HdYWY/qKbOUCC7FvSaadhELvBczUK+c/E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778587999; c=relaxed/simple; bh=R9/nh0mO0m1YKOfs7OiCWqAIrmDezsFxxZ0vqQit3KI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MIXWsGgtk+OBBiA7bWh9Pq3SpUia8Yi5UrSpqCxh6mpnM/422ACk3uxzq7JXeOg/Gu+doeILXNbz3PswqTO3gS3vdg1+/SqQrFZYhZQOBmAKpczps3ZvfoynU+MDJTQgSwrtNTylJXaQeq9JSrJmMmfGwR/wjkmgCavOaEi+xMo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 367D6C2BCF5; Tue, 12 May 2026 12:13:13 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 11/17] dmaengine: sh: rz-dmac: Drop the update of channel->chctrl with CHCTRL_SETEN Date: Tue, 12 May 2026 15:12:12 +0300 Message-ID: <20260512121219.216159-12-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The CHCTRL_SETEN bit is explicitly set in rz_dmac_enable_hw(). Updating struct rz_dmac_chan::chctrl with this bit in rz_dmac_prepare_desc_for_memcpy() and rz_dmac_prepare_descs_for_slave_sg() is unnecessary in the current code base. Moreover, it conflicts with the configuration sequence that will be used for cyclic DMA channels during suspend to RAM. Cyclic DMA support will be introduced in subsequent commits. This is a preparatory commit for cyclic DMA suspend to RAM support. Signed-off-by: Claudiu Beznea Reviewed-by: Frank Li --- Changes in v5: - none Changes in v4: - set channel->chctrl =3D 0 in rz_dmac_prepare_descs_for_slave_sg() Changes in v3: - none Changes in v2: - fixed typos in patch title and patch description drivers/dma/sh/rz-dmac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 2bf796dcc5f6..2de519b581b6 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -377,7 +377,7 @@ static void rz_dmac_prepare_desc_for_memcpy(struct rz_d= mac_chan *channel) rz_dmac_set_dma_req_no(dmac, channel->index, dmac->info->default_dma_req_= no); =20 channel->chcfg =3D chcfg; - channel->chctrl =3D CHCTRL_STG | CHCTRL_SETEN; + channel->chctrl =3D CHCTRL_STG; } =20 static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channe= l) @@ -428,7 +428,7 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct r= z_dmac_chan *channel) =20 rz_dmac_set_dma_req_no(dmac, channel->index, channel->mid_rid); =20 - channel->chctrl =3D CHCTRL_SETEN; + channel->chctrl =3D 0; } =20 static void rz_dmac_xfer_desc(struct rz_dmac_chan *chan) --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 59064495536; Tue, 12 May 2026 12:13:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588003; cv=none; b=hzX9kHzMgW9o5brJE6P9zGMh+Iz8jDepuT+QL9BsoY7rrhKSgVf8pys/7j8LPhkQlztb3Cc/gvTVzzvJnzO2q73RsagXvKjAlZmCrNxNQ19LyTcj/+u4q9DQsm+yyuXjHy23nDT1ASaPSFu4U4ePSKoVuitxRXFTtMAP8EjrOD8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588003; c=relaxed/simple; bh=9X9g/CU8G0YHhhwaET+v/14/On7q/ooXBqV/fKblSOQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YWzj0O3g54SHmPc6Wz7Rni+n9OMN5cDENZa5b8vzWMCnjwTTgkyryNeRrpLnKhhooXWPIrCv4/WFdOCiLtbKgeg1xneanplhpxXWEKZRHMTbh+UByXotc9vQ/KFV9ehKiy1Jew2CroMm71H+Ii88SAvOwkd26bM3pZ6UBU9dlxo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id EECE2C2BCF6; Tue, 12 May 2026 12:13:18 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 12/17] dmaengine: sh: rz-dmac: Add cyclic DMA support Date: Tue, 12 May 2026 15:12:13 +0300 Message-ID: <20260512121219.216159-13-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add cyclic DMA support to the RZ DMAC driver. A per-channel status bit is introduced to mark cyclic channels and is set during the DMA prepare callback. The IRQ handler checks this status bit and calls vchan_cyclic_callback() accordingly. Signed-off-by: Claudiu Beznea --- Changes in v5: - none Changes in v4: - drop the nxla update logic in rz_dmac_lmdesc_recycle() as this is not needed for any kind of transfers - drop the update of channel->status =3D 0 from rz_dmac_free_chan_resources= () and rz_dmac_terminate_all() as this was moved in patch 09/17 Changes in v3: - updated rz_dmac_lmdesc_recycle() to restore the lmdesc->nxla - in rz_dmac_prepare_descs_for_cyclic() update directly the desc->start_lmdesc with the descriptor pointer insted of the descriptor address - used rz_dmac_lmdesc_addr() to compute the descritor address - set channel->status =3D 0 in rz_dmac_free_chan_resources() - in rz_dmac_prep_dma_cyclic() check for invalid periods or buffer len and limit the critical area protected by spinlock - set channel->status =3D 0 in rz_dmac_terminate_all() - updated rz_dmac_calculate_residue_bytes_in_vd() to use=20 rz_dmac_lmdesc_addr() - dropped goto in rz_dmac_irq_handler_thread() as it is not needed anymore; dropped also the local variable desc Changes in v2: - none drivers/dma/sh/rz-dmac.c | 136 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 130 insertions(+), 6 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 2de519b581b6..d6ad070be705 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -35,6 +35,7 @@ enum rz_dmac_prep_type { RZ_DMAC_DESC_MEMCPY, RZ_DMAC_DESC_SLAVE_SG, + RZ_DMAC_DESC_CYCLIC, }; =20 struct rz_lmdesc { @@ -67,9 +68,11 @@ struct rz_dmac_desc { /** * enum rz_dmac_chan_status: RZ DMAC channel status * @RZ_DMAC_CHAN_STATUS_PAUSED: Channel is paused though DMA engine callba= cks + * @RZ_DMAC_CHAN_STATUS_CYCLIC: Channel is cyclic */ enum rz_dmac_chan_status { RZ_DMAC_CHAN_STATUS_PAUSED, + RZ_DMAC_CHAN_STATUS_CYCLIC, }; =20 struct rz_dmac_chan { @@ -191,6 +194,7 @@ struct rz_dmac { =20 /* LINK MODE DESCRIPTOR */ #define HEADER_LV BIT(0) +#define HEADER_WBD BIT(2) =20 #define RZ_DMAC_MAX_CHAN_DESCRIPTORS 16 #define RZ_DMAC_MAX_CHANNELS 16 @@ -431,6 +435,57 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct = rz_dmac_chan *channel) channel->chctrl =3D 0; } =20 +static void rz_dmac_prepare_descs_for_cyclic(struct rz_dmac_chan *channel) +{ + struct dma_chan *chan =3D &channel->vc.chan; + struct rz_dmac *dmac =3D to_rz_dmac(chan->device); + struct rz_dmac_desc *d =3D channel->desc; + size_t period_len =3D d->sgcount; + struct rz_lmdesc *lmdesc; + size_t buf_len =3D d->len; + size_t periods =3D buf_len / period_len; + + lockdep_assert_held(&channel->vc.lock); + + channel->chcfg |=3D CHCFG_SEL(channel->index) | CHCFG_DMS; + + if (d->direction =3D=3D DMA_DEV_TO_MEM) { + channel->chcfg |=3D CHCFG_SAD; + channel->chcfg &=3D ~CHCFG_REQD; + } else { + channel->chcfg |=3D CHCFG_DAD | CHCFG_REQD; + } + + lmdesc =3D channel->lmdesc.tail; + d->start_lmdesc =3D lmdesc; + + for (size_t i =3D 0; i < periods; i++) { + if (d->direction =3D=3D DMA_DEV_TO_MEM) { + lmdesc->sa =3D d->src; + lmdesc->da =3D d->dest + (i * period_len); + } else { + lmdesc->sa =3D d->src + (i * period_len); + lmdesc->da =3D d->dest; + } + + lmdesc->tb =3D period_len; + lmdesc->chitvl =3D 0; + lmdesc->chext =3D 0; + lmdesc->chcfg =3D channel->chcfg; + lmdesc->header =3D HEADER_LV | HEADER_WBD; + + if (i =3D=3D periods - 1) + lmdesc->nxla =3D rz_dmac_lmdesc_addr(channel, d->start_lmdesc); + + if (++lmdesc >=3D (channel->lmdesc.base + DMAC_NR_LMDESC)) + lmdesc =3D channel->lmdesc.base; + } + + channel->lmdesc.tail =3D lmdesc; + + rz_dmac_set_dma_req_no(dmac, channel->index, channel->mid_rid); +} + static void rz_dmac_xfer_desc(struct rz_dmac_chan *chan) { struct virt_dma_desc *vd; @@ -452,6 +507,10 @@ static void rz_dmac_xfer_desc(struct rz_dmac_chan *cha= n) case RZ_DMAC_DESC_SLAVE_SG: rz_dmac_prepare_descs_for_slave_sg(chan); break; + + case RZ_DMAC_DESC_CYCLIC: + rz_dmac_prepare_descs_for_cyclic(chan); + break; } =20 rz_dmac_enable_hw(chan); @@ -586,6 +645,55 @@ rz_dmac_prep_slave_sg(struct dma_chan *chan, struct sc= atterlist *sgl, return vchan_tx_prep(&channel->vc, &desc->vd, flags); } =20 +static struct dma_async_tx_descriptor * +rz_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, + size_t buf_len, size_t period_len, + enum dma_transfer_direction direction, + unsigned long flags) +{ + struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); + struct rz_dmac_desc *desc; + size_t periods; + + if (!is_slave_direction(direction)) + return NULL; + + if (!period_len || !buf_len) + return NULL; + + periods =3D buf_len / period_len; + if (!periods || periods > DMAC_NR_LMDESC) + return NULL; + + scoped_guard(spinlock_irqsave, &channel->vc.lock) { + if (channel->status & BIT(RZ_DMAC_CHAN_STATUS_CYCLIC)) + return NULL; + + desc =3D list_first_entry_or_null(&channel->ld_free, struct rz_dmac_desc= , node); + if (!desc) + return NULL; + + list_del(&desc->node); + + channel->status |=3D BIT(RZ_DMAC_CHAN_STATUS_CYCLIC); + } + + desc->type =3D RZ_DMAC_DESC_CYCLIC; + desc->sgcount =3D period_len; + desc->len =3D buf_len; + desc->direction =3D direction; + + if (direction =3D=3D DMA_DEV_TO_MEM) { + desc->src =3D channel->src_per_address; + desc->dest =3D buf_addr; + } else { + desc->src =3D buf_addr; + desc->dest =3D channel->dst_per_address; + } + + return vchan_tx_prep(&channel->vc, &desc->vd, flags); +} + static int rz_dmac_terminate_all(struct dma_chan *chan) { struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); @@ -733,9 +841,18 @@ static u32 rz_dmac_calculate_residue_bytes_in_vd(struc= t rz_dmac_chan *channel, } =20 /* Calculate residue from next lmdesc to end of virtual desc */ - while (lmdesc->chcfg & CHCFG_DEM) { - residue +=3D lmdesc->tb; - lmdesc =3D rz_dmac_get_next_lmdesc(channel->lmdesc.base, lmdesc); + if (channel->status & BIT(RZ_DMAC_CHAN_STATUS_CYCLIC)) { + u32 start_lmdesc_addr =3D rz_dmac_lmdesc_addr(channel, desc->start_lmdes= c); + + while (lmdesc->nxla !=3D start_lmdesc_addr) { + residue +=3D lmdesc->tb; + lmdesc =3D rz_dmac_get_next_lmdesc(channel->lmdesc.base, lmdesc); + } + } else { + while (lmdesc->chcfg & CHCFG_DEM) { + residue +=3D lmdesc->tb; + lmdesc =3D rz_dmac_get_next_lmdesc(channel->lmdesc.base, lmdesc); + } } =20 dev_dbg(dmac->dev, "%s: VD residue is %u\n", __func__, residue); @@ -928,10 +1045,14 @@ static irqreturn_t rz_dmac_irq_handler_thread(int ir= q, void *dev_id) if (!desc) return IRQ_HANDLED; =20 - vchan_cookie_complete(&desc->vd); - channel->desc =3D NULL; + if (channel->status & BIT(RZ_DMAC_CHAN_STATUS_CYCLIC)) { + vchan_cyclic_callback(&desc->vd); + } else { + vchan_cookie_complete(&desc->vd); + channel->desc =3D NULL; =20 - rz_dmac_xfer_desc(channel); + rz_dmac_xfer_desc(channel); + } =20 return IRQ_HANDLED; } @@ -1183,6 +1304,8 @@ static int rz_dmac_probe(struct platform_device *pdev) engine =3D &dmac->engine; dma_cap_set(DMA_SLAVE, engine->cap_mask); dma_cap_set(DMA_MEMCPY, engine->cap_mask); + dma_cap_set(DMA_CYCLIC, engine->cap_mask); + engine->directions =3D BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); engine->residue_granularity =3D DMA_RESIDUE_GRANULARITY_BURST; rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_0_7_COMMON_BASE + DCTRL); rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_8_15_COMMON_BASE + DCTRL); @@ -1194,6 +1317,7 @@ static int rz_dmac_probe(struct platform_device *pdev) engine->device_tx_status =3D rz_dmac_tx_status; engine->device_prep_slave_sg =3D rz_dmac_prep_slave_sg; engine->device_prep_dma_memcpy =3D rz_dmac_prep_dma_memcpy; + engine->device_prep_dma_cyclic =3D rz_dmac_prep_dma_cyclic; engine->device_config =3D rz_dmac_config; engine->device_terminate_all =3D rz_dmac_terminate_all; engine->device_issue_pending =3D rz_dmac_issue_pending; --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8095B4D8D9D; Tue, 12 May 2026 12:13:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588008; cv=none; b=qdP8+hsMg5j/xtJsvVjOwajbtHvNUBouXGZXrX9hbdIAWrtTLsP1WaLSYT5eJg+6FbdZeateLEBxUQ3OfFlxl3TYmbaY032pvIl1XIpqc67md3BQlYncIx91TPoyFWzVn5vF3MjrncmRTCTaPekmjROi2tJGnS5k02SSaJVdk4o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588008; c=relaxed/simple; bh=C1uzurnunbaZHN2hjU/EdY8OcHRWiCmz2+SqJSoaMQs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=C0yteYWToQqt/Jc3KFCQiSuzTZHTItW1UNSLhfVSiTfmlwD8eAoQfmMuJ4oXa3GvMLA6fH4Oo7Y6x6SayOFhqED/CPVKY2Z6fWSVyFM/qOvt6y2jleKpZCJ8wBSd6YPqJpz2CeZZbm1vi2NkEb0iHYYirrK9uoHyjbpG9QstPqk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77BB8C2BCF5; Tue, 12 May 2026 12:13:23 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 13/17] dmaengine: sh: rz-dmac: Add runtime PM support Date: Tue, 12 May 2026 15:12:14 +0300 Message-ID: <20260512121219.216159-14-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Protect the driver exposed APIs with runtime PM suspend/resume calls before accessing HW registers. As the current driver leaves runtime PM enabled in probe, the purpose of the changes in this patch is to avoid accessing HW registers after a failed system suspend leaves the runtime PM state of the device improperly reinitialized. In that case, the driver remains bound to the device, the APIs are still exposed, and any access to HW registers without runtime resuming the device may lead to synchronous aborts. This patch prepares the driver for suspend-to-RAM support. Signed-off-by: Claudiu Beznea --- Changes in v5: - none, this patch is new drivers/dma/sh/rz-dmac.c | 48 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index d6ad070be705..df91657fd5e3 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -488,7 +488,15 @@ static void rz_dmac_prepare_descs_for_cyclic(struct rz= _dmac_chan *channel) =20 static void rz_dmac_xfer_desc(struct rz_dmac_chan *chan) { + struct dma_chan *ch =3D &chan->vc.chan; + struct rz_dmac *dmac =3D to_rz_dmac(ch->device); struct virt_dma_desc *vd; + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return; =20 vd =3D vchan_next_desc(&chan->vc); if (!vd) { @@ -549,6 +557,12 @@ static void rz_dmac_free_chan_resources(struct dma_cha= n *chan) struct rz_dmac *dmac =3D to_rz_dmac(chan->device); struct rz_dmac_desc *desc, *_desc; unsigned long flags; + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return; =20 spin_lock_irqsave(&channel->vc.lock, flags); =20 @@ -697,8 +711,15 @@ rz_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_add= r_t buf_addr, static int rz_dmac_terminate_all(struct dma_chan *chan) { struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); + struct rz_dmac *dmac =3D to_rz_dmac(chan->device); unsigned long flags; LIST_HEAD(head); + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return ret; =20 spin_lock_irqsave(&channel->vc.lock, flags); rz_dmac_disable_hw(channel); @@ -807,6 +828,11 @@ static void rz_dmac_device_synchronize(struct dma_chan= *chan) =20 vchan_synchronize(&channel->vc); =20 + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return; + ret =3D read_poll_timeout(rz_dmac_ch_readl, chstat, !(chstat & CHSTAT_EN), 100, 100000, false, channel, CHSTAT, 1); if (ret < 0) @@ -909,8 +935,15 @@ static enum dma_status rz_dmac_tx_status(struct dma_ch= an *chan, struct dma_tx_state *txstate) { struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); + struct rz_dmac *dmac =3D to_rz_dmac(chan->device); enum dma_status status; u32 residue; + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return ret; =20 scoped_guard(spinlock_irqsave, &channel->vc.lock) { status =3D dma_cookie_status(chan, cookie, txstate); @@ -956,6 +989,13 @@ static int rz_dmac_device_pause_set(struct rz_dmac_cha= n *channel, static int rz_dmac_device_pause(struct dma_chan *chan) { struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); + struct rz_dmac *dmac =3D to_rz_dmac(chan->device); + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return ret; =20 guard(spinlock_irqsave)(&channel->vc.lock); =20 @@ -985,6 +1025,13 @@ static int rz_dmac_device_resume_set(struct rz_dmac_c= han *channel, static int rz_dmac_device_resume(struct dma_chan *chan) { struct rz_dmac_chan *channel =3D to_rz_dmac_chan(chan); + struct rz_dmac *dmac =3D to_rz_dmac(chan->device); + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return ret; =20 guard(spinlock_irqsave)(&channel->vc.lock); =20 @@ -1265,6 +1312,7 @@ static int rz_dmac_probe(struct platform_device *pdev) return dev_err_probe(&pdev->dev, PTR_ERR(dmac->rstc), "failed to get resets\n"); =20 + pm_runtime_irq_safe(&pdev->dev); pm_runtime_enable(&pdev->dev); ret =3D pm_runtime_resume_and_get(&pdev->dev); if (ret < 0) { --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AC0B5379C4F; Tue, 12 May 2026 12:13:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588012; cv=none; b=EL9+zxjxvytKWSD8rpD7fRQ+aPMAsQWNU7phNLAHujkgfGAsrt45U3jf8TnzBBJuuFhpPYAbl7IYMSt9MLB8hjsDrZFFoLNXsBArKV1MfdYE1Y3VX9FVjCZ74pwijjsnmX2oB25cC9W8vevCnadO+0ltEUkZFt3QxWXkYTYIyms= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588012; c=relaxed/simple; bh=8t65VgXhLIJLjonli8OKtYr5Wv0hGAfxcXujWKJJxSs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NPN+/TF7AR8c5w3aTXdmruVMVNMPtihDCrUQ9HDRCpCRqkDy+qgOvR5MCELYJsIBsX5R4QVaMuAZW4yfpfLWOCYoOpp4k56BlWHMIaaO1f9gnmn+g7UZ/vKTt/lq7+TidBD6CWaFODiTt0ODSEHLdENPCwD46Zo4Mfdjx+KYVwU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00654C2BCFB; Tue, 12 May 2026 12:13:27 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 14/17] dmaengine: sh: rz-dmac: Add suspend to RAM support Date: Tue, 12 May 2026 15:12:15 +0300 Message-ID: <20260512121219.216159-15-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The Renesas RZ/G3S SoC supports a power saving mode in which power to most of the SoC components is turned off, including the DMA IP. Add suspend to RAM support to save and restore the DMA IP registers. Cyclic DMA channels require special handling. Since they can be paused and resumed during system suspend/resume, the driver restores additional registers for these channels during the system resume phase. If a channel was not explicitly paused during suspend, the driver ensures that it is paused and resumed as part of the system suspend/resume flow. This might be the case of a serial device being used with no_console_suspend. For non-cyclic channels, the dev_pm_ops::prepare callback waits for all the ongoing transfers to complete before allowing suspend-to-RAM to proceed. Signed-off-by: Claudiu Beznea --- Changes in v5: - runtime PM enable in rz_dmac_suspend_prepare() and rz_dmac_suspend_recove= r() - initialize ret in rz_dmac_suspend() - in suspend/resume APIs changed the order b/w runtime PM and reset calls to follow the sequence present in remove and probe - in rz_dmac_suspend(): take into account the error code returned by pm_runtime_put_sync() - in rz_dmac_resume(): use "return errors ? : 0;" instead of "return errors ? : ret;" Changes in v4: - in rz_dmac_device_synchronize() kept the read_poll_timeout() as this doesn't fail anymore with the proper status return from ->device_tx_status() API in case the channel is paused; with it the patch description was updated - keep the cleanup path in rz_dmac_suspend() simpler to avoid confusion when using guard() - used SYSTEM_SLEEP_PM_OPS() as there is no need for having the suspend/resume callbacks being called in NOIRQ phase Changes in v3: - dropped RZ_DMAC_CHAN_STATUS_SYS_SUSPENDED - dropped read_poll_timeout() from rz_dmac_device_synchronze() as with audio drivers this times out all the time on suspend because the audio DMA is already paused when the rz_dmac_device_synchronize() is called; updated the commit description to describe this change - call rz_dmac_device_pause_internal() only if RZ_DMAC_CHAN_STATUS_PAUSED bit is not set or the device is enabled in HW - updated rz_dmac_device_resume_set() to have it simpler and cover the cases when it is called with the channel enabled or paused; updated the comment describing the covered use cases - call rz_dmac_device_resume_internal() only if RZ_DMAC_CHAN_STATUS_PAUSED_INTERNAL bit is set - in rz_dmac_chan_is_enabled() return -EAGAIN only if the channel is enabled in HW - in rz_dmac_suspend_recover() drop the update of RZ_DMAC_CHAN_STATUS_SYS_SUSPENDED as this is not available anymore - in rz_dmac_suspend() call rz_dmac_device_pause_internal() unconditionally as the logic is now handled inside the called function; also, do not ignore anymore the failure of internal suspend and abort the suspend instead - report channel internal resume failures in rz_dmac_resume() - use rz_dmac_disable_hw() instead of open coding it in rz_dmac_resume() - call rz_dmac_device_resume_internal() uncoditionally as the skip logic is now handled in the function itself - use NOIRQ_SYSTEM_SLEEP_PM_OPS() - didn't collect Tommaso's Tb tag as the series was changed a lot since v2 Changes in v2: - fixed typos in patch description - in rz_dmac_suspend_prepare(): return -EAGAIN based on the value returned by vchan_issue_pending() - in rz_dmac_suspend_recover(): clear RZ_DMAC_CHAN_STATUS_SYS_SUSPENDED for non cyclic channels - in rz_dmac_resume(): call rz_dmac_set_dma_req_no() only for cyclic channe= ls drivers/dma/sh/rz-dmac.c | 209 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 204 insertions(+), 5 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index df91657fd5e3..b0a8590f4a9d 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -69,10 +69,12 @@ struct rz_dmac_desc { * enum rz_dmac_chan_status: RZ DMAC channel status * @RZ_DMAC_CHAN_STATUS_PAUSED: Channel is paused though DMA engine callba= cks * @RZ_DMAC_CHAN_STATUS_CYCLIC: Channel is cyclic + * @RZ_DMAC_CHAN_STATUS_PAUSED_INTERNAL: Channel is paused through driver = internal logic */ enum rz_dmac_chan_status { RZ_DMAC_CHAN_STATUS_PAUSED, RZ_DMAC_CHAN_STATUS_CYCLIC, + RZ_DMAC_CHAN_STATUS_PAUSED_INTERNAL, }; =20 struct rz_dmac_chan { @@ -92,6 +94,10 @@ struct rz_dmac_chan { u32 chctrl; int mid_rid; =20 + struct { + u32 nxla; + } pm_state; + struct list_head ld_free; =20 struct { @@ -1002,20 +1008,57 @@ static int rz_dmac_device_pause(struct dma_chan *ch= an) return rz_dmac_device_pause_set(channel, BIT(RZ_DMAC_CHAN_STATUS_PAUSED)); } =20 +static int rz_dmac_device_pause_internal(struct rz_dmac_chan *channel) +{ + lockdep_assert_held(&channel->vc.lock); + + /* Skip channels explicitly paused by consummers or disabled. */ + if (channel->status & BIT(RZ_DMAC_CHAN_STATUS_PAUSED) || + !rz_dmac_chan_is_enabled(channel)) + return 0; + + return rz_dmac_device_pause_set(channel, BIT(RZ_DMAC_CHAN_STATUS_PAUSED_I= NTERNAL)); +} + static int rz_dmac_device_resume_set(struct rz_dmac_chan *channel, unsigned long clear_bitmask) { - int ret =3D 0; u32 val; + int ret; =20 lockdep_assert_held(&channel->vc.lock); =20 - /* Do not check CHSTAT_SUS but rely on HW capabilities. */ + /* + * We can be: + * + * 1/ after the channel was paused by a consummer and now it + * needs to be resummed + * 2/ after the channel was paused internally (as a result of + * a system suspend with power loss or not) + * 3/ after the channel was paused by a consummer, the system + * went through a system suspend (with power loss or not) + * and the consummer wants to resume the channel + * + * To cover all the above cases we set both CLRSUS and SETEN. + * + * In case 1/ setting SETEN while the channel is still enabled + * is harmless for the controller. + * + * In case 2/ the channel is disabled when calling this function + * and setting CLRSUS is harmless for the controller as the + * channel is disabled anyway. + * + * In case 3/ the channel is disabled/enabled if the system + * went though a suspend with power loss/or not and setting + * CLRSUS/SETEN is harmless for the controller as the channel + * is enabled/disabled anyway. + */ + + rz_dmac_ch_writel(channel, CHCTRL_CLRSUS | CHCTRL_SETEN, CHCTRL, 1); =20 - rz_dmac_ch_writel(channel, CHCTRL_CLRSUS, CHCTRL, 1); ret =3D read_poll_timeout_atomic(rz_dmac_ch_readl, val, - !(val & CHSTAT_SUS), 1, 1024, false, - channel, CHSTAT, 1); + ((val & (CHSTAT_SUS | CHSTAT_EN)) =3D=3D CHSTAT_EN), + 1, 1024, false, channel, CHSTAT, 1); =20 channel->status &=3D ~clear_bitmask; =20 @@ -1041,6 +1084,16 @@ static int rz_dmac_device_resume(struct dma_chan *ch= an) return rz_dmac_device_resume_set(channel, BIT(RZ_DMAC_CHAN_STATUS_PAUSED)= ); } =20 +static int rz_dmac_device_resume_internal(struct rz_dmac_chan *channel) +{ + lockdep_assert_held(&channel->vc.lock); + + if (!(channel->status & BIT(RZ_DMAC_CHAN_STATUS_PAUSED_INTERNAL))) + return 0; + + return rz_dmac_device_resume_set(channel, BIT(RZ_DMAC_CHAN_STATUS_PAUSED_= INTERNAL)); +} + /* * -----------------------------------------------------------------------= ------ * IRQ handling @@ -1406,6 +1459,151 @@ static void rz_dmac_remove(struct platform_device *= pdev) pm_runtime_disable(&pdev->dev); } =20 +static int rz_dmac_suspend_prepare(struct device *dev) +{ + struct rz_dmac *dmac =3D dev_get_drvdata(dev); + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return ret; + + for (unsigned int i =3D 0; i < dmac->n_channels; i++) { + struct rz_dmac_chan *channel =3D &dmac->channels[i]; + + guard(spinlock_irqsave)(&channel->vc.lock); + + /* Wait for transfer completion, except in cyclic case. */ + if (channel->status & BIT(RZ_DMAC_CHAN_STATUS_CYCLIC)) + continue; + + if (rz_dmac_chan_is_enabled(channel)) + return -EAGAIN; + } + + return 0; +} + +static void rz_dmac_suspend_recover(struct rz_dmac *dmac) +{ + int ret; + + PM_RUNTIME_ACQUIRE_IF_ENABLED(dmac->dev, pm); + ret =3D PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return; + + for (unsigned int i =3D 0; i < dmac->n_channels; i++) { + struct rz_dmac_chan *channel =3D &dmac->channels[i]; + + guard(spinlock_irqsave)(&channel->vc.lock); + + if (!(channel->status & BIT(RZ_DMAC_CHAN_STATUS_CYCLIC))) + continue; + + rz_dmac_device_resume_internal(channel); + } +} + +static int rz_dmac_suspend(struct device *dev) +{ + struct rz_dmac *dmac =3D dev_get_drvdata(dev); + int ret =3D 0; + + for (unsigned int i =3D 0; i < dmac->n_channels; i++) { + struct rz_dmac_chan *channel =3D &dmac->channels[i]; + + guard(spinlock_irqsave)(&channel->vc.lock); + + if (!(channel->status & BIT(RZ_DMAC_CHAN_STATUS_CYCLIC))) + continue; + + ret =3D rz_dmac_device_pause_internal(channel); + if (ret) { + dev_err(dev, "Failed to suspend channel %s\n", + dma_chan_name(&channel->vc.chan)); + break; + } + + channel->pm_state.nxla =3D rz_dmac_ch_readl(channel, NXLA, 1); + } + + if (ret) + goto suspend_recover; + + ret =3D reset_control_assert(dmac->rstc); + if (ret) + goto suspend_recover; + + ret =3D pm_runtime_put_sync(dev); + if (ret < 0) + goto reset_deassert; + + return 0; + +reset_deassert: + reset_control_deassert(dmac->rstc); +suspend_recover: + rz_dmac_suspend_recover(dmac); + return ret; +} + +static int rz_dmac_resume(struct device *dev) +{ + struct rz_dmac *dmac =3D dev_get_drvdata(dev); + int errors =3D 0, ret; + + ret =3D pm_runtime_resume_and_get(dev); + if (ret) + return ret; + + ret =3D reset_control_deassert(dmac->rstc); + if (ret) { + /* + * Do not put runtime PM here and keep the same state as in + * probe. As subsequent suspend/resume cycles may follow, leave + * the runtime PM as is, here, to avoid imbalances. + */ + return ret; + } + + rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_0_7_COMMON_BASE + DCTRL); + rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_8_15_COMMON_BASE + DCTRL); + + for (unsigned int i =3D 0; i < dmac->n_channels; i++) { + struct rz_dmac_chan *channel =3D &dmac->channels[i]; + + guard(spinlock_irqsave)(&channel->vc.lock); + + rz_dmac_disable_hw(&dmac->channels[i]); + + if (!(channel->status & BIT(RZ_DMAC_CHAN_STATUS_CYCLIC))) + continue; + + rz_dmac_set_dma_req_no(dmac, channel->index, channel->mid_rid); + + rz_dmac_ch_writel(channel, channel->pm_state.nxla, NXLA, 1); + rz_dmac_ch_writel(channel, channel->chcfg, CHCFG, 1); + rz_dmac_ch_writel(channel, CHCTRL_SWRST, CHCTRL, 1); + rz_dmac_ch_writel(channel, channel->chctrl, CHCTRL, 1); + + ret =3D rz_dmac_device_resume_internal(channel); + if (ret) { + errors =3D ret; + dev_err(dev, "Failed to resume channel %s, ret=3D%d\n", + dma_chan_name(&channel->vc.chan), ret); + } + } + + return errors ? : 0; +} + +static const struct dev_pm_ops rz_dmac_pm_ops =3D { + .prepare =3D rz_dmac_suspend_prepare, + SYSTEM_SLEEP_PM_OPS(rz_dmac_suspend, rz_dmac_resume) +}; + static const struct rz_dmac_info rz_dmac_v2h_info =3D { .icu_register_dma_req =3D rzv2h_icu_register_dma_req, .default_dma_req_no =3D RZV2H_ICU_DMAC_REQ_NO_DEFAULT, @@ -1432,6 +1630,7 @@ static struct platform_driver rz_dmac_driver =3D { .driver =3D { .name =3D "rz-dmac", .of_match_table =3D of_rz_dmac_match, + .pm =3D pm_sleep_ptr(&rz_dmac_pm_ops), }, .probe =3D rz_dmac_probe, .remove =3D rz_dmac_remove, --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 60F5138889C; Tue, 12 May 2026 12:13:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588017; cv=none; b=ULeQ7R/zL3QE1t+dFkqOHADYzoliSwvnNCU3k8EmdR8UVq8k01CeuVM7AorDBswdxMEzfuUxleHX8ZdavtMkz3lYaNP3rs5FfzizBAuVoiTuZ+f35RlG6Rlb+HrHwGiHWM92fLi8VE82u6+RalQvEG+heSmrkg56ByzQA4fGbiE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588017; c=relaxed/simple; bh=GuqZ+5BByRYIwSHpwJsCK4AGDxOAeXArdET2gFOVGkM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eme+4OX5WoStNVC42h4KF972sKn5om51brG5hNgXRY7yxXbFRgbW3WFO0Zh+QfD0laEKcvVqWBm7KjwLm9hPTfSyqjJ3epVU49lrmkO5F3Aij1+xjvLgiA6HkTUKlNHGSbzrwUqFyr0qTFuKpPe+qLQzn55k1TejWpumC41NuBE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9FE3AC2BCB0; Tue, 12 May 2026 12:13:32 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 15/17] ASoC: renesas: rz-ssi: Add pause support Date: Tue, 12 May 2026 15:12:16 +0300 Message-ID: <20260512121219.216159-16-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add pause support as a preparatory step to switch to PCM dmaengine APIs. Acked-by: Mark Brown Signed-off-by: Claudiu Beznea --- Changes in v5: - none Changes in v4: - collected tags Changes in v3: - none, this patch is new sound/soc/renesas/rz-ssi.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/sound/soc/renesas/rz-ssi.c b/sound/soc/renesas/rz-ssi.c index 71e434cfe07b..d4e1dded3a9c 100644 --- a/sound/soc/renesas/rz-ssi.c +++ b/sound/soc/renesas/rz-ssi.c @@ -847,6 +847,7 @@ static int rz_ssi_dai_trigger(struct snd_pcm_substream = *substream, int cmd, =20 switch (cmd) { case SNDRV_PCM_TRIGGER_RESUME: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: ret =3D rz_ssi_trigger_resume(ssi, strm); if (ret) return ret; @@ -888,6 +889,7 @@ static int rz_ssi_dai_trigger(struct snd_pcm_substream = *substream, int cmd, break; =20 case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: rz_ssi_stop(ssi, strm); break; =20 @@ -1054,7 +1056,8 @@ static const struct snd_pcm_hardware rz_ssi_pcm_hardw= are =3D { .info =3D SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | - SNDRV_PCM_INFO_RESUME, + SNDRV_PCM_INFO_RESUME | + SNDRV_PCM_INFO_PAUSE, .buffer_bytes_max =3D PREALLOC_BUFFER, .period_bytes_min =3D 32, .period_bytes_max =3D 8192, --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 15A1944E053; Tue, 12 May 2026 12:13:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588022; cv=none; b=a8HUFtyoJ8am3In2gXmc7XPsAv8wuW+EMJd3th0F+H4W4Hbmq3DjgP+psRGF+qjm8tmFq8+DKd6/dx8MOLmpP3/vPIWYPo9qS36D472p6AWj1wO0GTNNtpwF/1XprPF4JTUucNQISrdEs3emSnE+jQWM3i4vGPPCXnNgLy9srg8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588022; c=relaxed/simple; bh=e1AEbLalrnVih0/xHMEY1am+HimQCNOVLnpMxWNljjg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fBLY5SPCtDg5B1MeyUzizfqcVfZJ+x9GWXOUQp+PuATH5FFIUolj8LJ6QWBgGhKH05POVCtmwXUtgtXLSF2ywQWjK7JRVlKnGqkV7bP7uZxssGxEhmMvBS1OL1FjLyeiSM6Ow/ENfqTBhcdm7nIM0VPggzE7S7dcITZy2q+v/aY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59B3CC2BCF5; Tue, 12 May 2026 12:13:37 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 16/17] ASoC: renesas: rz-ssi: Use generic PCM dmaengine APIs Date: Tue, 12 May 2026 15:12:17 +0300 Message-ID: <20260512121219.216159-17-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" On Renesas RZ/G2L and RZ/G3S SoCs (where this was tested), captured audio files occasionally contained random spikes when viewed with a tool such as Audacity. These spikes were also audible as popping noises. Using cyclic DMA resolves this issue. The driver was reworked to use the existing support provided by the generic PCM dmaengine APIs. In addition to eliminating the random spikes, the following issues were addressed: - blank periods at the beginning of recorded files, which occurred intermittently, are no longer present - no overruns or underruns were observed when continuously recording short audio files (e.g. 5 seconds long) in a loop - concurrency issues in the SSI driver when enqueuing DMA requests were eliminated; previously, DMA requests could be prepared and submitted both from the DMA completion callback and the interrupt handler, which led to crashes after several hours of testing - the SSI driver logic is simplified - the number of generated interrupts is reduced by approximately 250% In the SSI platform driver probe function, the following changes were made: - the driver-specific DMA configuration was removed in favor of the generic PCM dmaengine APIs. As a result, explicit cleanup goto labels are no longer required and the driver remove callback was dropped, since resource management is now handled via devres helpers - special handling was added for IP variants operating in half-duplex mode, where the DMA channel name in the device tree is "rt"; this DMA channel name is taken into account and passed to the generic PCM dmaengine configuration data All code previously responsible for preparing and completing DMA transfers was removed, as this functionality is now handled entirely by the generic PCM dmaengine APIs. Since DMA channels must be paused and resumed during recovery paths (overruns and underruns reported by the hardware), the DMA channel references are stored in rz_ssi_hw_params(). The logic in rz_ssi_is_dma_enabled() was updated to reflect that the driver no longer manages DMA transfers directly. To avoid software reported underruns (e.g. when running aplay during consecutive suspend/resume cycles, or when the CPU is nearly 100% loaded), rz_ssi_pcm_hardware.buffer_bytes_max was increased to 192K. At the same time, rz_ssi_pcm_hardware.period_bytes_max was set to 48K to reduce interrupt overhead. Finally, rz_ssi_stream_is_play() was removed, as it had only a single remaining user after this rework, and its logic was inlined at the call site. Acked-by: Mark Brown Signed-off-by: Claudiu Beznea --- Changes in v5: - in rz_ssi_interrupt(): check if playback and capture dmas are the same to avoid calling dmaengine_pause() twice, on the same DMA channel - in rz_ssi_shutdown(): set ssi->dmas[i] =3D NULL - still preserved the Mark's Ack Changes in v4: - collected tags - in rz_ssi_interrupt() checked the dma channel is valid before calling dmaengine_pause(); at the same time initialized the rz_ssi->dmas[] with NULL in case the DMA is not available in rz_ssi_dai_hw_params() - set rz_ssi_dmaengine_pcm_conf.prealloc_buffer_size - dinamically allocate the object of type snd_dmaengine_pcm_config passed to devm_snd_dmaengine_pcm_register() to avoid issues when the driver is instantiated for more than one HW instance - I considered keeping the ack was still OK; Mark, please let me know if you consider otherwise Changes in v3: - s/CONFIG_SND_SOC_GENERIC_DMAENGINE_PCM/SND_SOC_GENERIC_DMAENGINE_PCM in Kconfig - in rz_ssi_clk_setup(): drop the update of dma_dai->maxburst - in rz_ssi_interrupt(): pause the DMA channels in case of HW over/underruns - add different open APIs for rz_ssi_soc_component_pio and rz_ssi_soc_component_dma=20 - set rz_ssi_pcm_hardware to rz_ssi_dmaengine_pcm_conf.pcm_hardware and updated the buffer_bytes_max to avoid underruns detected by applications just before suspending; along with it updated period_bytes_max for lower interrupt overhead; updated the patch description for this; with it updated the snd_pcm_set_managed_buffer_all() arguments to use the rz_ssi_pcm_hardware - added back rz_ssi_soc_component_pio.pcm_new instantiation as the PIO mode was broken w/o it - use specific rz_ssi_soc_component_dma.open implementation for DMA - updated rz_ssi_dmaengine_pcm_conf.chan_names[].{tx, rx} either if there is about full or half duplex instantiation and move the flags variable local to the code block that uses it - check devm_snd_dmaengine_pcm_register() for defer errors Changes in v2: - fixed typos in patch description - select CONFIG_SND_SOC_GENERIC_DMAENGINE_PCM for rz-ssi driver - in rz_ssi_dai_hw_params() check if DMA is enabled before calling snd_dmaengine_pcm_get_chan() to avoid failures for PIO mode - do not drop rz_ssi_pcm_pointer() and rz_ssi_pcm_new() as these are necessary for PIO mode - added 2 struct snd_soc_component_driver, one for PIO mode, one for DMA and updated probe() to register the proper snd_soc_component_driver based on the working mode sound/soc/renesas/Kconfig | 1 + sound/soc/renesas/rz-ssi.c | 388 ++++++++++++------------------------- 2 files changed, 130 insertions(+), 259 deletions(-) diff --git a/sound/soc/renesas/Kconfig b/sound/soc/renesas/Kconfig index 11c2027c88a7..6520217e7407 100644 --- a/sound/soc/renesas/Kconfig +++ b/sound/soc/renesas/Kconfig @@ -56,6 +56,7 @@ config SND_SOC_MSIOF config SND_SOC_RZ tristate "RZ/G2L series SSIF-2 support" depends on ARCH_RZG2L || COMPILE_TEST + select SND_SOC_GENERIC_DMAENGINE_PCM help This option enables RZ/G2L SSIF-2 sound support. =20 diff --git a/sound/soc/renesas/rz-ssi.c b/sound/soc/renesas/rz-ssi.c index d4e1dded3a9c..5406f9a3547f 100644 --- a/sound/soc/renesas/rz-ssi.c +++ b/sound/soc/renesas/rz-ssi.c @@ -13,6 +13,8 @@ #include #include #include +#include +#include #include #include =20 @@ -87,8 +89,6 @@ struct rz_ssi_stream { struct rz_ssi_priv *priv; struct snd_pcm_substream *substream; int fifo_sample_size; /* sample capacity of SSI FIFO */ - int dma_buffer_pos; /* The address for the next DMA descriptor */ - int completed_dma_buf_pos; /* The address of the last completed DMA descr= iptor. */ int period_counter; /* for keeping track of periods transferred */ int buffer_pos; /* current frame position in the buffer */ int running; /* 0=3Dstopped, 1=3Drunning */ @@ -96,8 +96,6 @@ struct rz_ssi_stream { int uerr_num; int oerr_num; =20 - struct dma_chan *dma_ch; - int (*transfer)(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm); }; =20 @@ -108,7 +106,6 @@ struct rz_ssi_priv { struct clk *sfr_clk; struct clk *clk; =20 - phys_addr_t phys; int irq_int; int irq_tx; int irq_rx; @@ -148,9 +145,10 @@ struct rz_ssi_priv { unsigned int sample_width; unsigned int sample_bits; } hw_params_cache; -}; =20 -static void rz_ssi_dma_complete(void *data); + struct snd_dmaengine_dai_dma_data dma_dais[SNDRV_PCM_STREAM_LAST + 1]; + struct dma_chan *dmas[SNDRV_PCM_STREAM_LAST + 1]; +}; =20 static void rz_ssi_reg_writel(struct rz_ssi_priv *priv, uint reg, u32 data) { @@ -172,11 +170,6 @@ static void rz_ssi_reg_mask_setl(struct rz_ssi_priv *p= riv, uint reg, writel(val, (priv->base + reg)); } =20 -static inline bool rz_ssi_stream_is_play(struct snd_pcm_substream *substre= am) -{ - return substream->stream =3D=3D SNDRV_PCM_STREAM_PLAYBACK; -} - static inline struct rz_ssi_stream * rz_ssi_stream_get(struct rz_ssi_priv *ssi, struct snd_pcm_substream *subst= ream) { @@ -185,7 +178,7 @@ rz_ssi_stream_get(struct rz_ssi_priv *ssi, struct snd_p= cm_substream *substream) =20 static inline bool rz_ssi_is_dma_enabled(struct rz_ssi_priv *ssi) { - return (ssi->playback.dma_ch && (ssi->dma_rt || ssi->capture.dma_ch)); + return !ssi->playback.transfer && !ssi->capture.transfer; } =20 static void rz_ssi_set_substream(struct rz_ssi_stream *strm, @@ -215,8 +208,6 @@ static void rz_ssi_stream_init(struct rz_ssi_stream *st= rm, struct snd_pcm_substream *substream) { rz_ssi_set_substream(strm, substream); - strm->dma_buffer_pos =3D 0; - strm->completed_dma_buf_pos =3D 0; strm->period_counter =3D 0; strm->buffer_pos =3D 0; =20 @@ -242,12 +233,13 @@ static void rz_ssi_stream_quit(struct rz_ssi_priv *ss= i, dev_info(dev, "underrun =3D %d\n", strm->uerr_num); } =20 -static int rz_ssi_clk_setup(struct rz_ssi_priv *ssi, unsigned int rate, - unsigned int channels) +static int rz_ssi_clk_setup(struct rz_ssi_priv *ssi, struct snd_pcm_substr= eam *substream, + unsigned int rate, unsigned int channels) { static u8 ckdv[] =3D { 1, 2, 4, 8, 16, 32, 64, 128, 6, 12, 24, 48, 96 = }; unsigned int channel_bits =3D 32; /* System Word Length */ unsigned long bclk_rate =3D rate * channels * channel_bits; + struct snd_dmaengine_dai_dma_data *dma_dai; unsigned int div; unsigned int i; u32 ssicr =3D 0; @@ -290,6 +282,8 @@ static int rz_ssi_clk_setup(struct rz_ssi_priv *ssi, un= signed int rate, return -EINVAL; } =20 + dma_dai =3D &ssi->dma_dais[substream->stream]; + /* * DWL: Data Word Length =3D {16, 24, 32} bits * SWL: System Word Length =3D 32 bits @@ -298,12 +292,15 @@ static int rz_ssi_clk_setup(struct rz_ssi_priv *ssi, = unsigned int rate, switch (ssi->hw_params_cache.sample_width) { case 16: ssicr |=3D SSICR_DWL(1); + dma_dai->addr_width =3D DMA_SLAVE_BUSWIDTH_2_BYTES; break; case 24: ssicr |=3D SSICR_DWL(5) | SSICR_PDTA; + dma_dai->addr_width =3D DMA_SLAVE_BUSWIDTH_4_BYTES; break; case 32: ssicr |=3D SSICR_DWL(6); + dma_dai->addr_width =3D DMA_SLAVE_BUSWIDTH_4_BYTES; break; default: dev_err(ssi->dev, "Not support %u data width", @@ -344,7 +341,7 @@ static void rz_ssi_set_idle(struct rz_ssi_priv *ssi) =20 static int rz_ssi_start(struct rz_ssi_priv *ssi, struct rz_ssi_stream *str= m) { - bool is_play =3D rz_ssi_stream_is_play(strm->substream); + bool is_play =3D strm->substream->stream =3D=3D SNDRV_PCM_STREAM_PLAYBACK; bool is_full_duplex; u32 ssicr, ssifcr; =20 @@ -423,14 +420,6 @@ static int rz_ssi_stop(struct rz_ssi_priv *ssi, struct= rz_ssi_stream *strm) /* Disable TX/RX */ rz_ssi_reg_mask_setl(ssi, SSICR, SSICR_TEN | SSICR_REN, 0); =20 - /* Cancel all remaining DMA transactions */ - if (rz_ssi_is_dma_enabled(ssi)) { - if (ssi->playback.dma_ch) - dmaengine_terminate_async(ssi->playback.dma_ch); - if (ssi->capture.dma_ch) - dmaengine_terminate_async(ssi->capture.dma_ch); - } - rz_ssi_set_idle(ssi); =20 return 0; @@ -458,10 +447,6 @@ static void rz_ssi_pointer_update(struct rz_ssi_stream= *strm, int frames) snd_pcm_period_elapsed(strm->substream); strm->period_counter =3D current_period; } - - strm->completed_dma_buf_pos +=3D runtime->period_size; - if (strm->completed_dma_buf_pos >=3D runtime->buffer_size) - strm->completed_dma_buf_pos =3D 0; } =20 static int rz_ssi_pio_recv(struct rz_ssi_priv *ssi, struct rz_ssi_stream *= strm) @@ -606,12 +591,6 @@ static irqreturn_t rz_ssi_interrupt(int irq, void *dat= a) if (irq =3D=3D ssi->irq_int) { /* error or idle */ bool is_stopped =3D !!(ssisr & (SSISR_RUIRQ | SSISR_ROIRQ | SSISR_TUIRQ | SSISR_TOIRQ)); - int i, count; - - if (rz_ssi_is_dma_enabled(ssi)) - count =3D 4; - else - count =3D 1; =20 if (ssi->capture.substream && is_stopped) { if (ssisr & SSISR_RUIRQ) @@ -631,18 +610,34 @@ static irqreturn_t rz_ssi_interrupt(int irq, void *da= ta) rz_ssi_stop(ssi, strm_playback); } =20 + if (!rz_ssi_is_stream_running(&ssi->playback) && + !rz_ssi_is_stream_running(&ssi->capture) && + rz_ssi_is_dma_enabled(ssi)) { + if (ssi->dmas[SNDRV_PCM_STREAM_PLAYBACK]) + dmaengine_pause(ssi->dmas[SNDRV_PCM_STREAM_PLAYBACK]); + if (ssi->dmas[SNDRV_PCM_STREAM_CAPTURE] && + /* Avoid calling pause twice in case of half duplex. */ + ssi->dmas[SNDRV_PCM_STREAM_PLAYBACK] !=3D + ssi->dmas[SNDRV_PCM_STREAM_CAPTURE]) + dmaengine_pause(ssi->dmas[SNDRV_PCM_STREAM_CAPTURE]); + } + /* Clear all flags */ rz_ssi_reg_mask_setl(ssi, SSISR, SSISR_TOIRQ | SSISR_TUIRQ | SSISR_ROIRQ | SSISR_RUIRQ, 0); =20 /* Add/remove more data */ if (ssi->capture.substream && is_stopped) { - for (i =3D 0; i < count; i++) + if (rz_ssi_is_dma_enabled(ssi)) + dmaengine_resume(ssi->dmas[SNDRV_PCM_STREAM_CAPTURE]); + else strm_capture->transfer(ssi, strm_capture); } =20 if (ssi->playback.substream && is_stopped) { - for (i =3D 0; i < count; i++) + if (rz_ssi_is_dma_enabled(ssi)) + dmaengine_resume(ssi->dmas[SNDRV_PCM_STREAM_PLAYBACK]); + else strm_playback->transfer(ssi, strm_playback); } =20 @@ -679,153 +674,11 @@ static irqreturn_t rz_ssi_interrupt(int irq, void *d= ata) return IRQ_HANDLED; } =20 -static int rz_ssi_dma_slave_config(struct rz_ssi_priv *ssi, - struct dma_chan *dma_ch, bool is_play) -{ - struct dma_slave_config cfg; - - memset(&cfg, 0, sizeof(cfg)); - - cfg.direction =3D is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM; - cfg.dst_addr =3D ssi->phys + SSIFTDR; - cfg.src_addr =3D ssi->phys + SSIFRDR; - if (ssi->hw_params_cache.sample_width =3D=3D 16) { - cfg.src_addr_width =3D DMA_SLAVE_BUSWIDTH_2_BYTES; - cfg.dst_addr_width =3D DMA_SLAVE_BUSWIDTH_2_BYTES; - } else { - cfg.src_addr_width =3D DMA_SLAVE_BUSWIDTH_4_BYTES; - cfg.dst_addr_width =3D DMA_SLAVE_BUSWIDTH_4_BYTES; - } - - return dmaengine_slave_config(dma_ch, &cfg); -} - -static int rz_ssi_dma_transfer(struct rz_ssi_priv *ssi, - struct rz_ssi_stream *strm) -{ - struct snd_pcm_substream *substream =3D strm->substream; - struct dma_async_tx_descriptor *desc; - struct snd_pcm_runtime *runtime; - enum dma_transfer_direction dir; - u32 dma_paddr, dma_size; - int amount; - - if (!rz_ssi_stream_is_valid(ssi, strm)) - return -EINVAL; - - runtime =3D substream->runtime; - if (runtime->state =3D=3D SNDRV_PCM_STATE_DRAINING) - /* - * Stream is ending, so do not queue up any more DMA - * transfers otherwise we play partial sound clips - * because we can't shut off the DMA quick enough. - */ - return 0; - - dir =3D rz_ssi_stream_is_play(substream) ? DMA_MEM_TO_DEV : DMA_DEV_TO_ME= M; - - /* Always transfer 1 period */ - amount =3D runtime->period_size; - - /* DMA physical address and size */ - dma_paddr =3D runtime->dma_addr + frames_to_bytes(runtime, - strm->dma_buffer_pos); - dma_size =3D frames_to_bytes(runtime, amount); - desc =3D dmaengine_prep_slave_single(strm->dma_ch, dma_paddr, dma_size, - dir, - DMA_PREP_INTERRUPT | DMA_CTRL_ACK); - if (!desc) { - dev_err(ssi->dev, "dmaengine_prep_slave_single() fail\n"); - return -ENOMEM; - } - - desc->callback =3D rz_ssi_dma_complete; - desc->callback_param =3D strm; - - if (dmaengine_submit(desc) < 0) { - dev_err(ssi->dev, "dmaengine_submit() fail\n"); - return -EIO; - } - - /* Update DMA pointer */ - strm->dma_buffer_pos +=3D amount; - if (strm->dma_buffer_pos >=3D runtime->buffer_size) - strm->dma_buffer_pos =3D 0; - - /* Start DMA */ - dma_async_issue_pending(strm->dma_ch); - - return 0; -} - -static void rz_ssi_dma_complete(void *data) -{ - struct rz_ssi_stream *strm =3D (struct rz_ssi_stream *)data; - - if (!strm->running || !strm->substream || !strm->substream->runtime) - return; - - /* Note that next DMA transaction has probably already started */ - rz_ssi_pointer_update(strm, strm->substream->runtime->period_size); - - /* Queue up another DMA transaction */ - rz_ssi_dma_transfer(strm->priv, strm); -} - -static void rz_ssi_release_dma_channels(struct rz_ssi_priv *ssi) -{ - if (ssi->playback.dma_ch) { - dma_release_channel(ssi->playback.dma_ch); - ssi->playback.dma_ch =3D NULL; - if (ssi->dma_rt) - ssi->dma_rt =3D false; - } - - if (ssi->capture.dma_ch) { - dma_release_channel(ssi->capture.dma_ch); - ssi->capture.dma_ch =3D NULL; - } -} - -static int rz_ssi_dma_request(struct rz_ssi_priv *ssi, struct device *dev) -{ - ssi->playback.dma_ch =3D dma_request_chan(dev, "tx"); - if (IS_ERR(ssi->playback.dma_ch)) - ssi->playback.dma_ch =3D NULL; - - ssi->capture.dma_ch =3D dma_request_chan(dev, "rx"); - if (IS_ERR(ssi->capture.dma_ch)) - ssi->capture.dma_ch =3D NULL; - - if (!ssi->playback.dma_ch && !ssi->capture.dma_ch) { - ssi->playback.dma_ch =3D dma_request_chan(dev, "rt"); - if (IS_ERR(ssi->playback.dma_ch)) { - ssi->playback.dma_ch =3D NULL; - goto no_dma; - } - - ssi->dma_rt =3D true; - } - - if (!rz_ssi_is_dma_enabled(ssi)) - goto no_dma; - - return 0; - -no_dma: - rz_ssi_release_dma_channels(ssi); - - return -ENODEV; -} - static int rz_ssi_trigger_resume(struct rz_ssi_priv *ssi, struct rz_ssi_st= ream *strm) { struct snd_pcm_substream *substream =3D strm->substream; - struct snd_pcm_runtime *runtime =3D substream->runtime; int ret; =20 - strm->dma_buffer_pos =3D strm->completed_dma_buf_pos + runtime->period_si= ze; - if (rz_ssi_is_stream_running(&ssi->playback) || rz_ssi_is_stream_running(&ssi->capture)) return 0; @@ -834,7 +687,7 @@ static int rz_ssi_trigger_resume(struct rz_ssi_priv *ss= i, struct rz_ssi_stream * if (ret) return ret; =20 - return rz_ssi_clk_setup(ssi, ssi->hw_params_cache.rate, + return rz_ssi_clk_setup(ssi, substream, ssi->hw_params_cache.rate, ssi->hw_params_cache.channels); } =20 @@ -843,7 +696,7 @@ static int rz_ssi_dai_trigger(struct snd_pcm_substream = *substream, int cmd, { struct rz_ssi_priv *ssi =3D snd_soc_dai_get_drvdata(dai); struct rz_ssi_stream *strm =3D rz_ssi_stream_get(ssi, substream); - int ret =3D 0, i, num_transfer =3D 1; + int ret =3D 0; =20 switch (cmd) { case SNDRV_PCM_TRIGGER_RESUME: @@ -858,28 +711,7 @@ static int rz_ssi_dai_trigger(struct snd_pcm_substream= *substream, int cmd, if (cmd =3D=3D SNDRV_PCM_TRIGGER_START) rz_ssi_stream_init(strm, substream); =20 - if (rz_ssi_is_dma_enabled(ssi)) { - bool is_playback =3D rz_ssi_stream_is_play(substream); - - if (ssi->dma_rt) - ret =3D rz_ssi_dma_slave_config(ssi, ssi->playback.dma_ch, - is_playback); - else - ret =3D rz_ssi_dma_slave_config(ssi, strm->dma_ch, - is_playback); - - /* Fallback to pio */ - if (ret < 0) { - ssi->playback.transfer =3D rz_ssi_pio_send; - ssi->capture.transfer =3D rz_ssi_pio_recv; - rz_ssi_release_dma_channels(ssi); - } else { - /* For DMA, queue up multiple DMA descriptors */ - num_transfer =3D 4; - } - } - - for (i =3D 0; i < num_transfer; i++) { + if (!rz_ssi_is_dma_enabled(ssi)) { ret =3D strm->transfer(ssi, strm); if (ret) return ret; @@ -975,6 +807,8 @@ static void rz_ssi_shutdown(struct snd_pcm_substream *s= ubstream, ssi->dup.tx_active =3D false; else ssi->dup.rx_active =3D false; + + ssi->dmas[substream->stream] =3D NULL; } =20 static bool rz_ssi_is_valid_hw_params(struct rz_ssi_priv *ssi, unsigned in= t rate, @@ -1026,6 +860,12 @@ static int rz_ssi_dai_hw_params(struct snd_pcm_substr= eam *substream, return -EINVAL; } =20 + /* Save the DMA channels for recovery. */ + if (rz_ssi_is_dma_enabled(ssi)) + ssi->dmas[substream->stream] =3D snd_dmaengine_pcm_get_chan(substream); + else + ssi->dmas[substream->stream] =3D NULL; + if (rz_ssi_is_stream_running(&ssi->playback) || rz_ssi_is_stream_running(&ssi->capture)) { if (rz_ssi_is_valid_hw_params(ssi, rate, channels, sample_width, sample_= bits)) @@ -1041,10 +881,21 @@ static int rz_ssi_dai_hw_params(struct snd_pcm_subst= ream *substream, if (ret) return ret; =20 - return rz_ssi_clk_setup(ssi, rate, channels); + return rz_ssi_clk_setup(ssi, substream, rate, channels); +} + +static int rz_ssi_dai_probe(struct snd_soc_dai *dai) +{ + struct rz_ssi_priv *ssi =3D snd_soc_dai_get_drvdata(dai); + + snd_soc_dai_init_dma_data(dai, &ssi->dma_dais[SNDRV_PCM_STREAM_PLAYBACK], + &ssi->dma_dais[SNDRV_PCM_STREAM_CAPTURE]); + + return 0; } =20 static const struct snd_soc_dai_ops rz_ssi_dai_ops =3D { + .probe =3D rz_ssi_dai_probe, .startup =3D rz_ssi_startup, .shutdown =3D rz_ssi_shutdown, .trigger =3D rz_ssi_dai_trigger, @@ -1058,9 +909,9 @@ static const struct snd_pcm_hardware rz_ssi_pcm_hardwa= re =3D { SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_PAUSE, - .buffer_bytes_max =3D PREALLOC_BUFFER, + .buffer_bytes_max =3D 192 * 1024, .period_bytes_min =3D 32, - .period_bytes_max =3D 8192, + .period_bytes_max =3D 48 * 1024, .channels_min =3D SSI_CHAN_MIN, .channels_max =3D SSI_CHAN_MAX, .periods_min =3D 1, @@ -1068,8 +919,8 @@ static const struct snd_pcm_hardware rz_ssi_pcm_hardwa= re =3D { .fifo_size =3D 32 * 2, }; =20 -static int rz_ssi_pcm_open(struct snd_soc_component *component, - struct snd_pcm_substream *substream) +static int rz_ssi_pcm_open_pio(struct snd_soc_component *component, + struct snd_pcm_substream *substream) { snd_soc_set_runtime_hwparams(substream, &rz_ssi_pcm_hardware); =20 @@ -1077,6 +928,13 @@ static int rz_ssi_pcm_open(struct snd_soc_component *= component, SNDRV_PCM_HW_PARAM_PERIODS); } =20 +static int rz_ssi_pcm_open_dma(struct snd_soc_component *component, + struct snd_pcm_substream *substream) +{ + return snd_pcm_hw_constraint_integer(substream->runtime, + SNDRV_PCM_HW_PARAM_PERIODS); +} + static snd_pcm_uframes_t rz_ssi_pcm_pointer(struct snd_soc_component *comp= onent, struct snd_pcm_substream *substream) { @@ -1093,7 +951,8 @@ static int rz_ssi_pcm_new(struct snd_soc_component *co= mponent, { snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV, rtd->card->snd_card->dev, - PREALLOC_BUFFER, PREALLOC_BUFFER_MAX); + rz_ssi_pcm_hardware.buffer_bytes_max, + rz_ssi_pcm_hardware.buffer_bytes_max); return 0; } =20 @@ -1116,16 +975,30 @@ static struct snd_soc_dai_driver rz_ssi_soc_dai[] = =3D { }, }; =20 -static const struct snd_soc_component_driver rz_ssi_soc_component =3D { +static const struct snd_soc_component_driver rz_ssi_soc_component_pio =3D { .name =3D "rz-ssi", - .open =3D rz_ssi_pcm_open, + .open =3D rz_ssi_pcm_open_pio, .pointer =3D rz_ssi_pcm_pointer, .pcm_new =3D rz_ssi_pcm_new, .legacy_dai_naming =3D 1, }; =20 +static const struct snd_soc_component_driver rz_ssi_soc_component_dma =3D { + .name =3D "rz-ssi", + .open =3D rz_ssi_pcm_open_dma, + .legacy_dai_naming =3D 1, +}; + +static const struct snd_dmaengine_pcm_config rz_ssi_dmaengine_pcm_conf =3D= { + .pcm_hardware =3D &rz_ssi_pcm_hardware, + .prealloc_buffer_size =3D 192 * 1024, + .prepare_slave_config =3D snd_dmaengine_pcm_prepare_slave_config, +}; + static int rz_ssi_probe(struct platform_device *pdev) { + const struct snd_soc_component_driver *component_driver; + struct device_node *np =3D pdev->dev.of_node; struct device *dev =3D &pdev->dev; struct rz_ssi_priv *ssi; struct clk *audio_clk; @@ -1141,7 +1014,6 @@ static int rz_ssi_probe(struct platform_device *pdev) if (IS_ERR(ssi->base)) return PTR_ERR(ssi->base); =20 - ssi->phys =3D res->start; ssi->clk =3D devm_clk_get(dev, "ssi"); if (IS_ERR(ssi->clk)) return PTR_ERR(ssi->clk); @@ -1165,16 +1037,43 @@ static int rz_ssi_probe(struct platform_device *pde= v) =20 ssi->audio_mck =3D ssi->audio_clk_1 ? ssi->audio_clk_1 : ssi->audio_clk_2; =20 - /* Detect DMA support */ - ret =3D rz_ssi_dma_request(ssi, dev); - if (ret < 0) { + ssi->dma_dais[SNDRV_PCM_STREAM_PLAYBACK].addr =3D (dma_addr_t)res->start = + SSIFTDR; + ssi->dma_dais[SNDRV_PCM_STREAM_CAPTURE].addr =3D (dma_addr_t)res->start = + SSIFRDR; + + if (of_property_present(np, "dma-names")) { + struct snd_dmaengine_pcm_config *config; + unsigned int flags =3D 0; + + config =3D devm_kzalloc(dev, sizeof(*config), GFP_KERNEL); + if (!config) + return -ENOMEM; + + config->pcm_hardware =3D rz_ssi_dmaengine_pcm_conf.pcm_hardware; + config->prealloc_buffer_size =3D rz_ssi_dmaengine_pcm_conf.prealloc_buff= er_size; + config->prepare_slave_config =3D rz_ssi_dmaengine_pcm_conf.prepare_slave= _config; + + if (of_property_match_string(np, "dma-names", "rt") =3D=3D 0) { + flags =3D SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX; + config->chan_names[SNDRV_PCM_STREAM_PLAYBACK] =3D "rt"; + } else { + config->chan_names[SNDRV_PCM_STREAM_PLAYBACK] =3D "tx"; + config->chan_names[SNDRV_PCM_STREAM_CAPTURE] =3D "rx"; + } + ret =3D devm_snd_dmaengine_pcm_register(&pdev->dev, config, flags); + } else { + ret =3D -ENODEV; + } + + if (ret =3D=3D -EPROBE_DEFER) { + return ret; + } else if (ret) { dev_warn(dev, "DMA not available, using PIO\n"); ssi->playback.transfer =3D rz_ssi_pio_send; ssi->capture.transfer =3D rz_ssi_pio_recv; + component_driver =3D &rz_ssi_soc_component_pio; } else { - dev_info(dev, "DMA enabled"); - ssi->playback.transfer =3D rz_ssi_dma_transfer; - ssi->capture.transfer =3D rz_ssi_dma_transfer; + dev_info(dev, "DMA enabled\n"); + component_driver =3D &rz_ssi_soc_component_dma; } =20 ssi->playback.priv =3D ssi; @@ -1185,17 +1084,13 @@ static int rz_ssi_probe(struct platform_device *pde= v) =20 /* Error Interrupt */ ssi->irq_int =3D platform_get_irq_byname(pdev, "int_req"); - if (ssi->irq_int < 0) { - ret =3D ssi->irq_int; - goto err_release_dma_chs; - } + if (ssi->irq_int < 0) + return ssi->irq_int; =20 ret =3D devm_request_irq(dev, ssi->irq_int, rz_ssi_interrupt, 0, dev_name(dev), ssi); - if (ret < 0) { - dev_err_probe(dev, ret, "irq request error (int_req)\n"); - goto err_release_dma_chs; - } + if (ret < 0) + return dev_err_probe(dev, ret, "irq request error (int_req)\n"); =20 if (!rz_ssi_is_dma_enabled(ssi)) { /* Tx and Rx interrupts (pio only) */ @@ -1236,43 +1131,19 @@ static int rz_ssi_probe(struct platform_device *pde= v) } =20 ssi->rstc =3D devm_reset_control_get_exclusive(dev, NULL); - if (IS_ERR(ssi->rstc)) { - ret =3D PTR_ERR(ssi->rstc); - goto err_release_dma_chs; - } + if (IS_ERR(ssi->rstc)) + return dev_err_probe(dev, PTR_ERR(ssi->rstc), "Failed to get reset\n"); =20 /* Default 0 for power saving. Can be overridden via sysfs. */ pm_runtime_set_autosuspend_delay(dev, 0); pm_runtime_use_autosuspend(dev); ret =3D devm_pm_runtime_enable(dev); - if (ret < 0) { - dev_err(dev, "Failed to enable runtime PM!\n"); - goto err_release_dma_chs; - } - - ret =3D devm_snd_soc_register_component(dev, &rz_ssi_soc_component, - rz_ssi_soc_dai, - ARRAY_SIZE(rz_ssi_soc_dai)); - if (ret < 0) { - dev_err(dev, "failed to register snd component\n"); - goto err_release_dma_chs; - } - - return 0; - -err_release_dma_chs: - rz_ssi_release_dma_channels(ssi); - - return ret; -} - -static void rz_ssi_remove(struct platform_device *pdev) -{ - struct rz_ssi_priv *ssi =3D dev_get_drvdata(&pdev->dev); - - rz_ssi_release_dma_channels(ssi); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to enable runtime PM!\n"); =20 - reset_control_assert(ssi->rstc); + return devm_snd_soc_register_component(dev, component_driver, + rz_ssi_soc_dai, + ARRAY_SIZE(rz_ssi_soc_dai)); } =20 static const struct of_device_id rz_ssi_of_match[] =3D { @@ -1307,7 +1178,6 @@ static struct platform_driver rz_ssi_driver =3D { .pm =3D pm_ptr(&rz_ssi_pm_ops), }, .probe =3D rz_ssi_probe, - .remove =3D rz_ssi_remove, }; =20 module_platform_driver(rz_ssi_driver); --=20 2.43.0 From nobody Fri Jun 12 21:41:01 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0921B4C77C2; Tue, 12 May 2026 12:13:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588027; cv=none; b=S3vrIaNzp+w239nqgZu34CubEFTup1I8fpnVN3/urdCDwyu4ROnhmlzcRolBYX9Mr9wtJoUEzR6qQ+mDqvBMRajaVXRfzpNHWww+kFd/oIdRAOLEKxT4APQ1KfogIpvNE6pP+w5wcdz8KOrPSZIiTeDex5ff2hdCvttH0G7nmZU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778588027; c=relaxed/simple; bh=3uzQdJwTZ6S8+MkTJnchLAs3gbdNqu6wAWmMoVaBats=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=D389jYl5lHXzbiDTBFRq9aDk+PGU8lwCjJwuj1Koguw0GilqkIKJtm/0972s49q363zuaoMy8D1VcfEBR1xDiPlQ13RLd7sXiZu4AC5bDPGVIMgma4sgBzX4BRUsfVxEqnmipaD1IYukVQyKjyvHR+d4/PEKdOlxczH/op4zx6A= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0437EC2BCB0; Tue, 12 May 2026 12:13:41 +0000 (UTC) From: Claudiu Beznea To: vkoul@kernel.org, Frank.Li@kernel.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, biju.das.jz@bp.renesas.com, prabhakar.mahadev-lad.rj@bp.renesas.com, p.zabel@pengutronix.de, geert+renesas@glider.be, fabrizio.castro.jz@renesas.com, kuninori.morimoto.gx@renesas.com, long.luu.ur@renesas.com Cc: claudiu.beznea@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea Subject: [PATCH v5 17/17] dmaengine: sh: rz-dmac: Set the Link End (LE) bit on the last descriptor Date: Tue, 12 May 2026 15:12:18 +0300 Message-ID: <20260512121219.216159-18-claudiu.beznea.uj@bp.renesas.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> References: <20260512121219.216159-1-claudiu.beznea.uj@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" On an RZ/G2L-based system, it has been observed that when the DMA channels for all enabled IPs are active (TX and RX for one serial IP, TX and RX for one audio IP, and TX and RX for one SPI IP), shortly after all of them are started, the system can become irrecoverably blocked. In one debug session the system did not block, and the DMA HW registers were inspected. It was found that the DER (Descriptor Error) bit in the CHSTAT register for one of the SPI DMA channels was set. According to the RZ/G2L HW Manual, Rev. 1.30, chapter 14.4.7 Channel Status Register n/nS (CHSTAT_n/nS), description of the DER bit, the DER bit is set when the LV (Link Valid) value loaded with a descriptor in link mode is 0. This means that the DMA engine has loaded an invalid descriptor (as defined in Table 14.14, Header Area, of the same manual). The same chapter states that when a descriptor error occurs, the transfer is stopped, but no DMA error interrupt is generated. Set the LE bit on the last descriptor of a transfer. This informs the DMA engine that this is the final descriptor for the transfer. Signed-off-by: Claudiu Beznea --- Changes in v5: - none Changes in v4: - none Changes in v3: - none Changes in v2: - none drivers/dma/sh/rz-dmac.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index b0a8590f4a9d..19095a5492bc 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -200,6 +200,7 @@ struct rz_dmac { =20 /* LINK MODE DESCRIPTOR */ #define HEADER_LV BIT(0) +#define HEADER_LE BIT(1) #define HEADER_WBD BIT(2) =20 #define RZ_DMAC_MAX_CHAN_DESCRIPTORS 16 @@ -382,7 +383,7 @@ static void rz_dmac_prepare_desc_for_memcpy(struct rz_d= mac_chan *channel) lmdesc->chcfg =3D chcfg; lmdesc->chitvl =3D 0; lmdesc->chext =3D 0; - lmdesc->header =3D HEADER_LV; + lmdesc->header =3D HEADER_LV | HEADER_LE; =20 rz_dmac_set_dma_req_no(dmac, channel->index, dmac->info->default_dma_req_= no); =20 @@ -425,7 +426,7 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct r= z_dmac_chan *channel) lmdesc->chext =3D 0; if (i =3D=3D (sg_len - 1)) { lmdesc->chcfg =3D (channel->chcfg & ~CHCFG_DEM); - lmdesc->header =3D HEADER_LV; + lmdesc->header =3D HEADER_LV | HEADER_LE; } else { lmdesc->chcfg =3D channel->chcfg; lmdesc->header =3D HEADER_LV; --=20 2.43.0