[PATCH 12/18] iommu/tegra-gart: Add IOMMU_DOMAIN_DMA support

Robin Murphy
2020-08-20T15:10:46Z

Now that arch/arm is wired up for default domains and iommu-dma,
implement the corresponding driver-side support for DMA domains.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
drivers/iommu/tegra-gart.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index fac720273889..e081387080f6 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -9,6 +9,7 @@

#define dev_fmt(fmt) "gart: " fmt

+#include <linux/dma-iommu.h>
#include <linux/io.h>
#include <linux/iommu.h>
#include <linux/moduleparam.h>
@@ -145,16 +146,22 @@ static struct iommu_domain *gart_iommu_domain_alloc(unsigned type)
{
struct iommu_domain *domain;

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

domain = kzalloc(sizeof(*domain), GFP_KERNEL);
- if (domain) {
- domain->geometry.aperture_start = gart_handle->iovmm_base;
- domain->geometry.aperture_end = gart_handle->iovmm_end - 1;
- domain->geometry.force_aperture = true;
+ if (!domain)
+ return NULL;
+
+ if (type == IOMMU_DOMAIN_DMA && iommu_get_dma_cookie(domain)) {
+ kfree(domain);
+ return NULL;
}

+ domain->geometry.aperture_start = gart_handle->iovmm_base;
+ domain->geometry.aperture_end = gart_handle->iovmm_end - 1;
+ domain->geometry.force_aperture = true;
+
return domain;
}

--
2.28.0.dirty