From nobody Sun Feb 8 12:19:37 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6447BC6FD18 for ; Fri, 31 Mar 2023 09:53:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230044AbjCaJxg (ORCPT ); Fri, 31 Mar 2023 05:53:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232032AbjCaJxG (ORCPT ); Fri, 31 Mar 2023 05:53:06 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 9019720336 for ; Fri, 31 Mar 2023 02:52:04 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A31922F4; Fri, 31 Mar 2023 02:52:48 -0700 (PDT) Received: from e112269-lin.cambridge.arm.com (e112269-lin.cambridge.arm.com [10.1.194.34]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D834D3F6C4; Fri, 31 Mar 2023 02:52:02 -0700 (PDT) From: Steven Price To: Heiko Stuebner , Joerg Roedel , Jason Gunthorpe Cc: Steven Price , Will Deacon , Robin Murphy , iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org, John Keeping Subject: [PATCH v4] iommu/rockchip: Add missing set_platform_dma_ops callback Date: Fri, 31 Mar 2023 10:51:54 +0100 Message-Id: <20230331095154.2671129-1-steven.price@arm.com> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Similar to exynos, we need a set_platform_dma_ops() callback for proper operation on ARM 32 bit after recent changes in the IOMMU framework (detach ops removal). But also the use of a NULL domain is confusing. Rework the code to add support for IOMMU_DOMAIN_IDENTITY and a singleton rk_identity_domain which is assigned to domain when using an identity mapping rather than "detaching". This makes the code easier to reason about. Signed-off-by: Steven Price Acked-by: Heiko Stuebner Tested-by: Heiko Stuebner --- Changes since v3[1]: * Added a dummy free callback to rk_identity_ops. [1] https://lore.kernel.org/r/20230330144604.2431436-1-steven.price%40arm.c= om drivers/iommu/rockchip-iommu.c | 61 ++++++++++++++++++++++++++-------- 1 file changed, 47 insertions(+), 14 deletions(-) diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index f30db22ea5d7..ea5a3088bb7e 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -124,6 +124,7 @@ struct rk_iommudata { =20 static struct device *dma_dev; static const struct rk_iommu_ops *rk_ops; +static struct iommu_domain rk_identity_domain; =20 static inline void rk_table_flush(struct rk_iommu_domain *dom, dma_addr_t = dma, unsigned int count) @@ -646,7 +647,7 @@ static irqreturn_t rk_iommu_irq(int irq, void *dev_id) * Ignore the return code, though, since we always zap cache * and clear the page fault anyway. */ - if (iommu->domain) + if (iommu->domain !=3D &rk_identity_domain) report_iommu_fault(iommu->domain, iommu->dev, iova, flags); else @@ -980,26 +981,27 @@ static int rk_iommu_enable(struct rk_iommu *iommu) return ret; } =20 -static void rk_iommu_detach_device(struct iommu_domain *domain, - struct device *dev) +static int rk_iommu_identity_attach(struct iommu_domain *identity_domain, + struct device *dev) { struct rk_iommu *iommu; - struct rk_iommu_domain *rk_domain =3D to_rk_domain(domain); + struct rk_iommu_domain *rk_domain; unsigned long flags; int ret; =20 /* Allow 'virtual devices' (eg drm) to detach from domain */ iommu =3D rk_iommu_from_dev(dev); if (!iommu) - return; + return -ENODEV; + + rk_domain =3D to_rk_domain(iommu->domain); =20 dev_dbg(dev, "Detaching from iommu domain\n"); =20 - /* iommu already detached */ - if (iommu->domain !=3D domain) - return; + if (iommu->domain =3D=3D identity_domain) + return 0; =20 - iommu->domain =3D NULL; + iommu->domain =3D identity_domain; =20 spin_lock_irqsave(&rk_domain->iommus_lock, flags); list_del_init(&iommu->node); @@ -1011,8 +1013,31 @@ static void rk_iommu_detach_device(struct iommu_doma= in *domain, rk_iommu_disable(iommu); pm_runtime_put(iommu->dev); } + + return 0; } =20 +static void rk_iommu_identity_free(struct iommu_domain *domain) +{ +} + +static struct iommu_domain_ops rk_identity_ops =3D { + .attach_dev =3D rk_iommu_identity_attach, + .free =3D rk_iommu_identity_free, +}; + +static struct iommu_domain rk_identity_domain =3D { + .type =3D IOMMU_DOMAIN_IDENTITY, + .ops =3D &rk_identity_ops, +}; + +#ifdef CONFIG_ARM +static void rk_iommu_set_platform_dma(struct device *dev) +{ + WARN_ON(rk_iommu_identity_attach(&rk_identity_domain, dev)); +} +#endif + static int rk_iommu_attach_device(struct iommu_domain *domain, struct device *dev) { @@ -1035,8 +1060,9 @@ static int rk_iommu_attach_device(struct iommu_domain= *domain, if (iommu->domain =3D=3D domain) return 0; =20 - if (iommu->domain) - rk_iommu_detach_device(iommu->domain, dev); + ret =3D rk_iommu_identity_attach(&rk_identity_domain, dev); + if (ret) + return ret; =20 iommu->domain =3D domain; =20 @@ -1050,7 +1076,7 @@ static int rk_iommu_attach_device(struct iommu_domain= *domain, =20 ret =3D rk_iommu_enable(iommu); if (ret) - rk_iommu_detach_device(iommu->domain, dev); + WARN_ON(rk_iommu_identity_attach(&rk_identity_domain, dev)); =20 pm_runtime_put(iommu->dev); =20 @@ -1061,6 +1087,9 @@ static struct iommu_domain *rk_iommu_domain_alloc(uns= igned type) { struct rk_iommu_domain *rk_domain; =20 + if (type =3D=3D IOMMU_DOMAIN_IDENTITY) + return &rk_identity_domain; + if (type !=3D IOMMU_DOMAIN_UNMANAGED && type !=3D IOMMU_DOMAIN_DMA) return NULL; =20 @@ -1176,6 +1205,7 @@ static int rk_iommu_of_xlate(struct device *dev, iommu_dev =3D of_find_device_by_node(args->np); =20 data->iommu =3D platform_get_drvdata(iommu_dev); + data->iommu->domain =3D &rk_identity_domain; dev_iommu_priv_set(dev, data); =20 platform_device_put(iommu_dev); @@ -1188,6 +1218,9 @@ static const struct iommu_ops rk_iommu_ops =3D { .probe_device =3D rk_iommu_probe_device, .release_device =3D rk_iommu_release_device, .device_group =3D rk_iommu_device_group, +#ifdef CONFIG_ARM + .set_platform_dma_ops =3D rk_iommu_set_platform_dma, +#endif .pgsize_bitmap =3D RK_IOMMU_PGSIZE_BITMAP, .of_xlate =3D rk_iommu_of_xlate, .default_domain_ops =3D &(const struct iommu_domain_ops) { @@ -1343,7 +1376,7 @@ static int __maybe_unused rk_iommu_suspend(struct dev= ice *dev) { struct rk_iommu *iommu =3D dev_get_drvdata(dev); =20 - if (!iommu->domain) + if (iommu->domain =3D=3D &rk_identity_domain) return 0; =20 rk_iommu_disable(iommu); @@ -1354,7 +1387,7 @@ static int __maybe_unused rk_iommu_resume(struct devi= ce *dev) { struct rk_iommu *iommu =3D dev_get_drvdata(dev); =20 - if (!iommu->domain) + if (iommu->domain =3D=3D &rk_identity_domain) return 0; =20 return rk_iommu_enable(iommu); --=20 2.39.2