From nobody Fri Oct 2 08:24:45 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 ADE1A524AE8; Tue, 29 Sep 2026 12:38:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790685494; cv=none; b=mkckStkbkLc8rDNhitrZPZS+S6G0DmVtZnrbU04gKJR0byEGx4NmqUGCL8LVIN82k8/l3xGo7ccBVerHdGL+STP6F0D7+Qzikuq5DdAYXNV4wUYYonXcXBrCEG+7HZ1gXbDRjnvrkp5ynotHyjzy/NdK1IfMyYSyk1Hs8pLUwRE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790685494; c=relaxed/simple; bh=PnJBgVnbIgcWLNLYch9cQewKsDFIC4Led3KTymkokH4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CU/fxtEElOTKJ/QP5TqHcZaQeWCR7pv0C9LOz6JKG0ZRroq0GFsCZji4nN90LsJ0M+khW/N4dE3AvJV1AxfLWC3Ad7RLZiSzjIGwX+W5JEymnBOOZGfX4WRWWT1xzdjmVSzF4HGsGKQZ81qAd/HvAvzNKvCwUk2f3NjB2RCYIHo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=W62Ep8tg; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="W62Ep8tg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D70B91F00893; Tue, 29 Sep 2026 12:38:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790685493; bh=xQvqh5V0jEHbs9qUBqtF9FaB1INU8MfQPD5WaPzmvXE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=W62Ep8tgE+ySxjojeOR3jnKlHVdgP8VdVCPFperhYxYzy9sg3KDEAgZ9VEMvbROou 564WHbkJgnXg5x1Ui5KOc0qCXRLOqEhWxCDwZo+fPgIOq6tBxzfVS8LXK/Q6F8N6DA HyZr6IQqSHaXM8nCNCvx31w4nB43XOvZAmhSqKYiTgAIGMFgEuw+ACJU/0/OJAhXmy nEfxVSBnFzWuM2CLX1uQWGu1zSJbr2lsEluML0KL6U/np56tNTsxV0UBEPhgtBoH0d RKVZxZ/pg+s/EUy/6JTa/Uwr0VFJ1P/lb/LRbhmbmH6RQBaILTGLZMP8KXS/JgPuAu IbICRk56PkHOw== From: Jisheng Zhang To: Mark Brown , Joseph Steel Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 1/5] spi: dw: use DW_SPI_ISR directly Date: Tue, 29 Sep 2026 20:18:13 +0800 Message-ID: <20260929121817.20896-2-jszhang@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260929121817.20896-1-jszhang@kernel.org> References: <20260929121817.20896-1-jszhang@kernel.org> 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 DW_SPI_ISR register reports the masked interrupts, no need to mask again. Signed-off-by: Jisheng Zhang --- drivers/spi/spi-dw-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index 206d3f9dd83d..1c060f0ec50c 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -275,7 +275,7 @@ static irqreturn_t dw_spi_irq(int irq, void *dev_id) { struct spi_controller *ctlr =3D dev_id; struct dw_spi *dws =3D spi_controller_get_devdata(ctlr); - u16 irq_status =3D dw_readl(dws, DW_SPI_ISR) & DW_SPI_INT_MASK; + u16 irq_status =3D dw_readl(dws, DW_SPI_ISR); =20 if (!irq_status) return IRQ_NONE; --=20 2.53.0 From nobody Fri Oct 2 08:24:45 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 BD693496D31; Tue, 29 Sep 2026 12:38:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790685497; cv=none; b=oBu27wt1+irsAs60p+BrcJUJ5VEos+XgBAPk69CWiM3DC5FvFUhUAm5VTdoPLYoIbpY/zlsPpIrjhf5yKx0WEUwu/uzpm3ReZjRn0SiJ15h9F2LFFtnJV2vjvUreJMO9aksdPuuzYhgWaUF6Ijeq5j/ExAV9Th0WeA9vc5RlYhc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790685497; c=relaxed/simple; bh=YoBqXSNWbmIJDpbWGo5PSN1FJHiwmzLJwcB374omhe4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=t2cc/XvBL8UtFZJgD5XEljmy+vjXhKhPLfyodXmEfuk+5SVPaWbXPUk8Bzkm8gfuvJQjJtWHL54Mmykkv3mtn4u7I6TSdGbDKqyVtgyKORQw2DpAwsv4g5jDU/TgxkhU5SkL1zHR3XChFPFKzonp9jokrvHcMALa3fBVgMmK+OQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Yz3hc+6R; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Yz3hc+6R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A84961F0089A; Tue, 29 Sep 2026 12:38:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790685495; bh=yAQ2P8CHyaU39zrns5eUxUPj6PC6Gwq9Dx1e55SbnRg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Yz3hc+6RgR95Sl4+oLMp7RZZxMmjGQN7yMdN0YehlyDLwa33ThvIFSoVGeev/go+J hIrlFtYWE9gvywxaZlTpLfuOsekIbPGkyodyo32G5VMp6lYbYrGdds394qNF55f5/8 IOxre0newjbw3Or+tlEDZyhopp03NpkFfu0JN1xKuBqYWNIYhVwwdxCwlxDP4hGVfK hBRX9TiHe/TcB7DtXWlH/P2svgT0i1cTqy0vdKBFq3Gm7qdEMZp7E3xuvKAyETGgiN dQPYlFholB6mX6cNyNu6X5h6VnN+njzhR55USyMPSxloidpitly1KW+tGf0drK6P0w bXtfs4H5Pa+Ng== From: Jisheng Zhang To: Mark Brown , Joseph Steel Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 2/5] spi: dw: remove useless dws->transfer_handler check Date: Tue, 29 Sep 2026 20:18:14 +0800 Message-ID: <20260929121817.20896-3-jszhang@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260929121817.20896-1-jszhang@kernel.org> References: <20260929121817.20896-1-jszhang@kernel.org> 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" transfer_handler is initialized before any DW SPI interrupt is unmasked. While the IRQ is registered but the handler is NULL, dw_spi_hw_init() has all DW SPI interrupts disabled. Therefore dw_spi_irq() cannot observe a DW SPI interrupt with a NULL transfer_handler. Signed-off-by: Jisheng Zhang --- drivers/spi/spi-dw-core.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index 1c060f0ec50c..f4c4e9dae25e 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -280,8 +280,7 @@ static irqreturn_t dw_spi_irq(int irq, void *dev_id) if (!irq_status) return IRQ_NONE; =20 - if (!dws->transfer_handler || - (!ctlr->cur_msg && dws->transfer_handler =3D=3D dw_spi_transfer_handl= er)) { + if (!ctlr->cur_msg && dws->transfer_handler =3D=3D dw_spi_transfer_handle= r) { dw_spi_mask_intr(dws, 0xff); return IRQ_HANDLED; } --=20 2.53.0 From nobody Fri Oct 2 08:24:45 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 3A9E1524AF9; Tue, 29 Sep 2026 12:38:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; 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Tue, 29 Sep 2026 12:38:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790685496; bh=neytlIQXdUaSH2YGaKdqCIIZLNyrglaw5V1+1H8MeMc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=I5sCsvBlrUPNRmrKN5CgO2xwlg0B40eO6Y/wOo8c8UMxHKD0QHrJGm8rf1DPZdVCi XGClQKYeJ4FBu6BaB2tNE5nKv6Dho/hhiTkyLKcCjDojmw3sYRNlPtjOaCvwujVMRS Zci6oIq9KQzcX+qo3thAb4Twd5ry7iEbQLy2kWACLRXw+wlbbuZAs8eUTa25YS0hMO vFI2PZuUmHiBwL+2se/ESEK+w1IKghzSQDJM8EffilxNgyUY2AXoDdYKoygScO54iF ofxKPeXRyDl6gOaYT4StcxmfI+R2eqqFqbd9rzgGmPcEFV70FvfrQSEZbH6lB3TRaf 9vjz60EsicYZQ== From: Jisheng Zhang To: Mark Brown , Joseph Steel Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 3/5] spi: dw: remove duplicated "!rx_len && !tx_len" handling from dw_spi_irq Date: Tue, 29 Sep 2026 20:18:15 +0800 Message-ID: <20260929121817.20896-4-jszhang@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260929121817.20896-1-jszhang@kernel.org> References: <20260929121817.20896-1-jszhang@kernel.org> 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" dw_spi_irq() need not handle enhanced-transfer's "!rx_len && !tx_len" case as that state is already handled by dw_spi_enh_handler() Signed-off-by: Jisheng Zhang --- drivers/spi/spi-dw-core.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index f4c4e9dae25e..91de357f97f3 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -284,12 +284,6 @@ static irqreturn_t dw_spi_irq(int irq, void *dev_id) dw_spi_mask_intr(dws, 0xff); return IRQ_HANDLED; } - if (dws->transfer_handler =3D=3D dw_spi_enh_handler && - !dws->rx_len && !dws->tx_len) { - dw_spi_mask_intr(dws, 0xff); - spi_finalize_current_transfer(ctlr); - return IRQ_HANDLED; - } =20 return dws->transfer_handler(dws); } --=20 2.53.0 From nobody Fri Oct 2 08:24:45 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 BB55D524AF4; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dxs21gkd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35C3A1F00898; Tue, 29 Sep 2026 12:38:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790685498; bh=ov9JwG7dTxYqZs760mQ1kon32dW5uXkE9+e7+SDMk24=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=dxs21gkdX6rAPQH7a9fsAlBEu1oEvWxE+vvfllmHdUyl3P9REdXWaTlh2woFWtcrg lbC66DaQ+bDgppbMmB49UQdxnu3WMzAA8Yf/eB4fryFtWF4s+tcrS7gaJvggLuIKo9 4OpmkQghX6GAGo+yIqlfm1DCkyhuJPQfkuraqQW7lxNm/4ikrV0JAWD3lP3+Y9ou5F KCegNbweTBSeDdGO90Gm/2xQzY8DHEGdd8YS6Z4j5ZNdSMMV30Y3MdH9AB+b90RZ/P 1Un2U+jzHEx+OYlJFrZuTG2UfOL/BM9IqZvM8c0K8te1+BR4hyoSOb6k6UiTXTKHQb gOhwxzJ5oGBzg== From: Jisheng Zhang To: Mark Brown , Joseph Steel Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 4/5] spi: dw: restore previous irq handling behavior when !ctlr->cur_msg Date: Tue, 29 Sep 2026 20:18:16 +0800 Message-ID: <20260929121817.20896-5-jszhang@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260929121817.20896-1-jszhang@kernel.org> References: <20260929121817.20896-1-jszhang@kernel.org> 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" Recent "enhanced" support changes the dw_spi_irq() behavior a bit when !!ctlr->cur_msg: if (!ctlr->cur_msg && dws->transfer_handler =3D=3D dw_spi_transfer_hand= ler) { dw_spi_mask_intr(dws, 0xff); return IRQ_HANDLED; } But it misses the dma case, where the transfer_handler =3D=3D dw_spi_dma_transfer_handler, so this changes the previous long time working behavior, let's restore the previous handling by only filtering out the dw_spi_enh_handler. Signed-off-by: Jisheng Zhang --- drivers/spi/spi-dw-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index 91de357f97f3..da7d4872e513 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -280,7 +280,7 @@ static irqreturn_t dw_spi_irq(int irq, void *dev_id) if (!irq_status) return IRQ_NONE; =20 - if (!ctlr->cur_msg && dws->transfer_handler =3D=3D dw_spi_transfer_handle= r) { + if (!ctlr->cur_msg && dws->transfer_handler !=3D dw_spi_enh_handler) { dw_spi_mask_intr(dws, 0xff); return IRQ_HANDLED; } --=20 2.53.0 From nobody Fri Oct 2 08:24:45 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7EF43528439; Tue, 29 Sep 2026 12:38:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790685502; cv=none; b=i19g9gcKiAoGNWFj7zja5fXdmTniH22C0JJOxUuzKxaL54yZkcuEl9LCz+smR3m8EiC5CnAVh//MZeLNn1YqhFq/OOEROnjFC+UcE5SKxgKhj0iPoFn9xaMEP7l8/fkFn7v5lAf8XBcbvorYBf5FoPQoqtwhtZhSRl3dl7VrxKU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790685502; c=relaxed/simple; bh=IIRWm7X+L5whAybhd2Ti0m0bZtAz9JahezDgaMJxjl4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RJuQZfH4ulmrp4mGLgA+hxG+IdwpzN/c/Ur6Aqk6vdrFz5g6uAzuhLplq3rkY8SCcxqNxJNQbLR9YiPDuWEZBRBqjuUnAehwsAk8XHD75gTIYoE4uj93s9itU9EKqYXzZMd0/nKfI9oN03i5fnuXsufZzah5WL3AXNTZME07a8s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ca28aGvM; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ca28aGvM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C7E201F00893; Tue, 29 Sep 2026 12:38:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790685500; bh=5r86svmXaUvZkvutPi56IOBmX8MkvlkgG4CpprlIsuQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Ca28aGvMzwfRUB2EvGlgPQhK1RFyt/G5oSnQjAbmfQrFPV0D7XJbbncFrvcqzg4sj XDPifwSDsfApWjc9jGekUAxWymoJgWr0IeOlBtjH+8rIw2jSWZq6j0dGWq9cFVkq6z RJT/bazBCmcsuo1ry85/j2hInLq/xd5OTF0PgDNUjHFKPHAXAgI4J2OKWD4hVADoqd T0muYUBwS7K+bciuyOV2klc8FIqoxjmCQGhqC66M0Cxe5FB7uSvSm8rgKrYNIVtyT8 EqGFeL1FcnE5phH+Suojx40IkhLEBH54dANGmelO8iEcbWdeTAKyc5dTB49zpZyI2V li17axB2eBGVQ== From: Jisheng Zhang To: Mark Brown , Joseph Steel Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 5/5] spi: dw: use threaded interrupt and optimize the threaded ISR Date: Tue, 29 Sep 2026 20:18:17 +0800 Message-ID: <20260929121817.20896-6-jszhang@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260929121817.20896-1-jszhang@kernel.org> References: <20260929121817.20896-1-jszhang@kernel.org> 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" To avoid blocking for an excessive amount of time, eventually impacting on system responsiveness, hard interrupt handlers should finish executing in as little time as possible. Use threaded interrupt and move the SPI transfer handling to an interrupt thread when non-native CS and host only. After that, since the dw_reader() and dw_writer() are called in threaded ISR now, so we can delay the unmasking interrupts until no rx and tx action is taken, thus reduce the interrupt numbers further. Tested with below two cmds ./spidev_test -D /dev/spidev1.3 -s 30000000 -S 327680 -I 1 ./spidev_test -D /dev/spidev1.3 -s 30000000 -S 327680 -I 1000 ./rtla timerlat top -q -k -P f:95 The first cmd is to check the interrupt numbers optmizaion result, the 2nd cmd group is to check the threaded interrupt improvement. Before the patch: each 320KB spi spidev_test transfer triggers 33118 interrupts spidev_test reports ~22090 kbps and rtla reports: Timer Latency 0 00:00:37 | IRQ Timer Latency (us) | Thread Ti= mer Latency (us) CPU COUNT | cur min avg max | cur mi= n avg max 0 #9958 | 1 0 67 103394 | 6 = 4 2198 105031 1 #36902 | 1 0 1 18 | 5 = 4 5 29 After the patch: each 320KB spi spidev_test transfer only triggers 1 interrupts spidev_test reports ~23520 kbps and now rtla reports: Timer Latency 0 00:00:58 | IRQ Timer Latency (us) | Thread Ti= mer Latency (us) CPU COUNT | cur min avg max | cur mi= n avg max 0 #58362 | 1 0 0 29 | 6 = 3 4 56 1 #58363 | 1 0 1 23 | 6 = 4 5 68 In summary: before the patch after the patch 33118 interrutps 1 interrupts reduced by 33117 times! 103394 us max latency 29 us max latency reduced by 3564 times! 22090 kbps rate 23520 kbps rate improved by 6.5% Signed-off-by: Jisheng Zhang --- drivers/spi/spi-dw-core.c | 67 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 62 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index da7d4872e513..bd86cbe8fcfe 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -132,10 +132,11 @@ static inline u32 dw_spi_rx_max(struct dw_spi *dws) return min_t(u32, dws->rx_len, dw_readl(dws, DW_SPI_RXFLR)); } =20 -static void dw_writer(struct dw_spi *dws) +static u32 dw_writer(struct dw_spi *dws) { u32 max =3D dw_spi_tx_max(dws); u32 txw =3D 0; + u32 tx =3D 0; =20 while (max--) { if (dws->tx) { @@ -150,13 +151,16 @@ static void dw_writer(struct dw_spi *dws) } dw_write_io_reg(dws, DW_SPI_DR, txw); --dws->tx_len; + ++tx; } + return tx; } =20 -static void dw_reader(struct dw_spi *dws) +static u32 dw_reader(struct dw_spi *dws) { u32 max =3D dw_spi_rx_max(dws); u32 rxw; + u32 rx =3D 0; =20 while (max--) { rxw =3D dw_read_io_reg(dws, DW_SPI_DR); @@ -171,7 +175,9 @@ static void dw_reader(struct dw_spi *dws) dws->rx +=3D dws->n_bytes; } --dws->rx_len; + ++rx; } + return rx; } =20 int dw_spi_check_status(struct dw_spi *dws, bool raw) @@ -210,6 +216,51 @@ int dw_spi_check_status(struct dw_spi *dws, bool raw) } EXPORT_SYMBOL_NS_GPL(dw_spi_check_status, "SPI_DW_CORE"); =20 +static irqreturn_t dw_spi_irq_thread_fn(int irq, void *dev_id) +{ + struct spi_controller *ctlr =3D dev_id; + struct dw_spi *dws =3D spi_controller_get_devdata(ctlr); + u32 rx, tx, imask, mask =3D 0; + bool finalize =3D false; + + do { + /* + * Read data from the Rx FIFO every time we've got a chance executing + * this method. If there is nothing left to receive, terminate the + * procedure. Otherwise adjust the Rx FIFO Threshold level if it's a + * final stage of the transfer. By doing so we'll get the next IRQ + * right when the leftover incoming data is received. + */ + rx =3D dw_reader(dws); + if (!dws->rx_len) { + mask |=3D 0xff; + finalize =3D true; + } else if (dws->rx_len <=3D dw_readl(dws, DW_SPI_RXFTLR)) { + dw_writel(dws, DW_SPI_RXFTLR, dws->rx_len - 1); + } + + /* + * Send data out as much as possible. The Tx FIFO Empty IRQ will be + * disabled after the data transmission is finished so not to + * have the TXE IRQ flood at the final stage of the transfer. + */ + tx =3D dw_writer(dws); + if (!dws->tx_len) + mask |=3D DW_SPI_INT_TXEI; + cond_resched(); + } while (rx !=3D 0 || tx !=3D 0); + + imask =3D DW_SPI_INT_TXEI | DW_SPI_INT_TXOI | + DW_SPI_INT_RXUI | DW_SPI_INT_RXOI | DW_SPI_INT_RXFI; + imask &=3D ~mask; + dw_spi_umask_intr(dws, imask); + + if (finalize) + spi_finalize_current_transfer(dws->ctlr); + + return IRQ_HANDLED; +} + static irqreturn_t dw_spi_transfer_handler(struct dw_spi *dws) { u16 irq_status =3D dw_readl(dws, DW_SPI_ISR); @@ -245,7 +296,13 @@ static irqreturn_t dw_spi_transfer_handler(struct dw_s= pi *dws) dw_spi_mask_intr(dws, DW_SPI_INT_TXEI); } =20 - return IRQ_HANDLED; + if (spi_controller_is_target(dws->ctlr) || !dws->rx_len || !dws->tx_len || + !spi_get_csgpiod(dws->ctlr->cur_msg->spi, 0)) { + return IRQ_HANDLED; + } else { + dw_spi_mask_intr(dws, 0xff); + return IRQ_WAKE_THREAD; + } } =20 static irqreturn_t dw_spi_enh_handler(struct dw_spi *dws) @@ -1305,8 +1362,8 @@ int dw_spi_add_controller(struct device *dev, struct = dw_spi *dws) /* Basic HW init */ dw_spi_hw_init(dev, dws); =20 - ret =3D request_irq(dws->irq, dw_spi_irq, IRQF_SHARED, dev_name(dev), - ctlr); + ret =3D request_threaded_irq(dws->irq, dw_spi_irq, dw_spi_irq_thread_fn, + IRQF_SHARED, dev_name(dev), ctlr); if (ret < 0 && ret !=3D -ENOTCONN) { dev_err(dev, "can not request IRQ\n"); goto err_free_ctlr; --=20 2.53.0