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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8432ac28-e91a-48f8-c5da-08db6e9c4be4 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Jun 2023 19:02:57.2096 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: xo3hQky/RWgqvR/tBzImuNwyuKAg9b3MbkHx4ofQ0363QPc6bJLEHCTyog6D1xXh X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ1PR12MB6051 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230616_120317_961470_68EE4A67 X-CRM114-Status: GOOD ( 23.07 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Even though dma-iommu.c and CONFIG_ARM_DMA_USE_IOMMU do approximately the same stuff, the way they relate to the IOMMU core is quiet different. dma-iommu.c expects the core code to setup an UNMANAGED domain (of type IOMMU_DOMAIN_DMA) and then configures itself to use that domain. This becomes the default_domain for the group. ARM_DMA_USE_IOMMU does not use the default_domain, instead it directly allocates an UNMANAGED domain and operates it just like an external driver. In this case group->default_domain is NULL. If the driver provides a global static identity_domain then automatically use it as the default_domain when in ARM_DMA_USE_IOMMU mode. This allows drivers that implemented default_domain == NULL as an IDENTITY translation to trivially get a properly labeled non-NULL default_domain on ARM32 configs. With this arrangment when ARM_DMA_USE_IOMMU wants to disconnect from the device the normal detach_domain flow will restore the IDENTITY domain as the default domain. Overall this makes attach_dev() of the IDENTITY domain called in the same places as detach_dev(). This effectively migrates these drivers to default_domain mode. For drivers that support ARM64 they will gain support for the IDENTITY translation mode for the dma_api and behave in a uniform way. Drivers use this by setting ops->identity_domain to a static singleton iommu_domain that implements the identity attach. If the core detects ARM_DMA_USE_IOMMU mode then it automatically attaches the IDENTITY domain during probe. Drivers can continue to prevent the use of DMA translation by returning IOMMU_DOMAIN_IDENTITY from def_domain_type, this will completely prevent IOMMU_DMA from running but will not impact ARM_DMA_USE_IOMMU. This allows removing the set_platform_dma_ops() from every remaining driver. Remove the set_platform_dma_ops from rockchip and mkt_v1 as all it does is set an existing global static identity domain. mkt_v1 does not support IOMMU_DOMAIN_DMA and it does not compile on ARM64 so this transformation is safe. Tested-by: Steven Price Tested-by: Marek Szyprowski Tested-by: Nicolin Chen Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommu.c | 26 +++++++++++++++++++++++--- drivers/iommu/mtk_iommu_v1.c | 12 ------------ drivers/iommu/rockchip-iommu.c | 10 ---------- 3 files changed, 23 insertions(+), 25 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 0c4fc46c210366..7ca70e2a3f51e9 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1757,15 +1757,35 @@ static int iommu_get_default_domain_type(struct iommu_group *group, int type; lockdep_assert_held(&group->mutex); + + /* + * ARM32 drivers supporting CONFIG_ARM_DMA_USE_IOMMU can declare an + * identity_domain and it will automatically become their default + * domain. Later on ARM_DMA_USE_IOMMU will install its UNMANAGED domain. + * Override the selection to IDENTITY if we are sure the driver supports + * it. + */ + if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) && ops->identity_domain) { + type = IOMMU_DOMAIN_IDENTITY; + if (best_type && type && best_type != type) + goto err; + best_type = target_type = IOMMU_DOMAIN_IDENTITY; + } + for_each_group_device(group, gdev) { type = best_type; if (ops->def_domain_type) { type = ops->def_domain_type(gdev->dev); - if (best_type && type && best_type != type) + if (best_type && type && best_type != type) { + /* Stick with the last driver override we saw */ + best_type = type; goto err; + } } - if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted) { + /* No ARM32 using systems will set untrusted, it cannot work. */ + if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted && + !WARN_ON(IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU))) { type = IOMMU_DOMAIN_DMA; if (best_type && type && best_type != type) goto err; @@ -1790,7 +1810,7 @@ static int iommu_get_default_domain_type(struct iommu_group *group, "Device needs domain type %s, but device %s in the same iommu group requires type %s - using default\n", iommu_domain_type_str(type), dev_name(last_dev), iommu_domain_type_str(best_type)); - return 0; + return best_type; } static void iommu_group_do_probe_finalize(struct device *dev) diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index cc3e7d53d33ad9..7c0c1d50df5f75 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -337,11 +337,6 @@ static struct iommu_domain mtk_iommu_v1_identity_domain = { .ops = &mtk_iommu_v1_identity_ops, }; -static void mtk_iommu_v1_set_platform_dma(struct device *dev) -{ - mtk_iommu_v1_identity_attach(&mtk_iommu_v1_identity_domain, dev); -} - static int mtk_iommu_v1_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t pgsize, size_t pgcount, int prot, gfp_t gfp, size_t *mapped) @@ -457,11 +452,6 @@ static int mtk_iommu_v1_create_mapping(struct device *dev, struct of_phandle_arg return 0; } -static int mtk_iommu_v1_def_domain_type(struct device *dev) -{ - return IOMMU_DOMAIN_IDENTITY; -} - static struct iommu_device *mtk_iommu_v1_probe_device(struct device *dev) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); @@ -599,10 +589,8 @@ static const struct iommu_ops mtk_iommu_v1_ops = { .probe_device = mtk_iommu_v1_probe_device, .probe_finalize = mtk_iommu_v1_probe_finalize, .release_device = mtk_iommu_v1_release_device, - .def_domain_type = mtk_iommu_v1_def_domain_type, .device_group = generic_device_group, .pgsize_bitmap = MT2701_IOMMU_PAGE_SIZE, - .set_platform_dma_ops = mtk_iommu_v1_set_platform_dma, .owner = THIS_MODULE, .default_domain_ops = &(const struct iommu_domain_ops) { .attach_dev = mtk_iommu_v1_attach_device, diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index 4fbede269e6712..818748a76e2469 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -1026,13 +1026,6 @@ static struct iommu_domain rk_identity_domain = { .ops = &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) { @@ -1211,9 +1204,6 @@ static const struct iommu_ops rk_iommu_ops = { .probe_device = rk_iommu_probe_device, .release_device = rk_iommu_release_device, .device_group = rk_iommu_device_group, -#ifdef CONFIG_ARM - .set_platform_dma_ops = rk_iommu_set_platform_dma, -#endif .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP, .of_xlate = rk_iommu_of_xlate, .default_domain_ops = &(const struct iommu_domain_ops) {