[PATCH v15 08/19] drm/etnaviv: Fix wrong caching mode being used for non writecombine buffers

[Sui Jingfeng]

In the etnaviv_gem_vmap_impl() function, the driver vmap whatever buffers
with write combine(WC) page property. This is incorrect, as some platforms
are cached coherent. Cached buffers should be mapped with cached page
property.

Fixes: a0a5ab3e99b8 ("drm/etnaviv: call correct function when trying to vmap a 
DMABUF")
Signed-off-by: Sui Jingfeng <sui.jingf...@linux.dev>
---
 drivers/gpu/drm/etnaviv/etnaviv_gem.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c 
b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
index 1fd2cff20ef4..b899aea64e22 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
@@ -393,6 +393,7 @@ static void etnaviv_gem_object_vunmap(struct drm_gem_object 
*obj,
 static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
 {
        struct page **pages;
+       pgprot_t prot;
 
        lockdep_assert_held(&obj->lock);
 
@@ -400,8 +401,19 @@ static void *etnaviv_gem_vmap_impl(struct 
etnaviv_gem_object *obj)
        if (IS_ERR(pages))
                return NULL;
 
-       return vmap(pages, obj->base.size >> PAGE_SHIFT,
-                       VM_MAP, pgprot_writecombine(PAGE_KERNEL));
+       switch (obj->flags) {
+       case ETNA_BO_CACHED:
+               prot = PAGE_KERNEL;
+               break;
+       case ETNA_BO_UNCACHED:
+               prot = pgprot_noncached(PAGE_KERNEL);
+               break;
+       case ETNA_BO_WC:
+       default:
+               prot = pgprot_writecombine(PAGE_KERNEL);
+       }
+
+       return vmap(pages, obj->base.size >> PAGE_SHIFT, VM_MAP, prot);
 }
 
 static inline enum dma_data_direction etnaviv_op_to_dma_dir(u32 op)
-- 
2.43.0