diff options
author | Jason Gunthorpe <jgg@nvidia.com> | 2023-09-13 16:43:42 +0300 |
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committer | Joerg Roedel <jroedel@suse.de> | 2023-09-25 12:40:57 +0300 |
commit | e98befd010bd56b8b3f2afea2d600e30df023e6b (patch) | |
tree | af3f5f4e4cf61510a86335312dfc300212c442ac /drivers/iommu/mtk_iommu_v1.c | |
parent | 59ddce4418da483c932bc7a08b88d6ba14020e83 (diff) | |
download | linux-e98befd010bd56b8b3f2afea2d600e30df023e6b.tar.xz |
iommu: Allow an IDENTITY domain as the default_domain in ARM32
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 <steven.price@arm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/9-v8-81230027b2fa+9d-iommu_all_defdom_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/mtk_iommu_v1.c')
-rw-r--r-- | drivers/iommu/mtk_iommu_v1.c | 12 |
1 files changed, 0 insertions, 12 deletions
diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index cc3e7d53d33a..7c0c1d50df5f 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, |