[PATCH v5 5/5] iommu/tegra-smmu: Support managed domains

Thierry Reding
2022-05-12T19:01:23Z

From: Navneet Kumar <navneetk@nvidia.com>

Allow creating identity and DMA API compatible IOMMU domains. When
creating a DMA API compatible domain, make sure to also create the
required cookie.

Signed-off-by: Navneet Kumar <navneetk@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
---
Changes in v5:
- remove DMA cookie initialization that's now no longer needed

drivers/iommu/tegra-smmu.c | 37 ++++++++++++++++++++-----------------
1 file changed, 20 insertions(+), 17 deletions(-)

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 93879c40056c..f8b2b863c111 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -16,6 +16,7 @@
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/dma-mapping.h>
+#include <linux/dma-iommu.h>

#include <soc/tegra/ahb.h>
#include <soc/tegra/mc.h>
@@ -277,7 +278,9 @@ static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
{
struct tegra_smmu_as *as;

- if (type != IOMMU_DOMAIN_UNMANAGED)
+ if (type != IOMMU_DOMAIN_UNMANAGED &&
+ type != IOMMU_DOMAIN_DMA &&
+ type != IOMMU_DOMAIN_IDENTITY)
return NULL;

as = kzalloc(sizeof(*as), GFP_KERNEL);
@@ -287,25 +290,16 @@ static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
as->attr = SMMU_PD_READABLE | SMMU_PD_WRITABLE | SMMU_PD_NONSECURE;

as->pd = alloc_page(GFP_KERNEL | __GFP_DMA | __GFP_ZERO);
- if (!as->pd) {
- kfree(as);
- return NULL;
- }
+ if (!as->pd)
+ goto free_as;

as->count = kcalloc(SMMU_NUM_PDE, sizeof(u32), GFP_KERNEL);
- if (!as->count) {
- __free_page(as->pd);
- kfree(as);
- return NULL;
- }
+ if (!as->count)
+ goto free_pd_range;

as->pts = kcalloc(SMMU_NUM_PDE, sizeof(*as->pts), GFP_KERNEL);
- if (!as->pts) {
- kfree(as->count);
- __free_page(as->pd);
- kfree(as);
- return NULL;
- }
+ if (!as->pts)
+ goto free_pts;

spin_lock_init(&as->lock);

@@ -315,6 +309,15 @@ static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
as->domain.geometry.force_aperture = true;

return &as->domain;
+
+free_pts:
+ kfree(as->pts);
+free_pd_range:
+ __free_page(as->pd);
+free_as:
+ kfree(as);
+
+ return NULL;
}

static void tegra_smmu_domain_free(struct iommu_domain *domain)
@@ -1009,7 +1012,7 @@ static const struct iommu_ops tegra_smmu_ops = {
.probe_device = tegra_smmu_probe_device,
.release_device = tegra_smmu_release_device,
.device_group = tegra_smmu_device_group,
- .get_resv_regions = of_iommu_get_resv_regions,
+ .get_resv_regions = iommu_dma_get_resv_regions,
.put_resv_regions = generic_iommu_put_resv_regions,
.of_xlate = tegra_smmu_of_xlate,
.pgsize_bitmap = SZ_4K,
--
2.36.1