[PATCH v1 1/6] drm/panfrost: Set IOMMU_CACHE flag
From: Ariel D'Alessandro
Date: Mon Mar 10 2025 - 16:00:36 EST
Panfrost does not support uncached mappings, so flag them properly. Also
flag the pages that are mapped as response to a page fault as cached.
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Signed-off-by: Ariel D'Alessandro <ariel.dalessandro@xxxxxxxxxxxxx>
---
drivers/gpu/drm/panfrost/panfrost_mmu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
index b91019cd5acb1..9e6f198ef5c1b 100644
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -327,7 +327,7 @@ int panfrost_mmu_map(struct panfrost_gem_mapping *mapping)
struct drm_gem_object *obj = &shmem->base;
struct panfrost_device *pfdev = to_panfrost_device(obj->dev);
struct sg_table *sgt;
- int prot = IOMMU_READ | IOMMU_WRITE;
+ int prot = IOMMU_READ | IOMMU_WRITE | IOMMU_CACHE;
if (WARN_ON(mapping->active))
return 0;
@@ -528,7 +528,7 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as,
goto err_map;
mmu_map_sg(pfdev, bomapping->mmu, addr,
- IOMMU_WRITE | IOMMU_READ | IOMMU_NOEXEC, sgt);
+ IOMMU_WRITE | IOMMU_READ | IOMMU_CACHE | IOMMU_NOEXEC, sgt);
bomapping->active = true;
bo->heap_rss_size += SZ_2M;
--
2.47.2