Am Sonntag, dem 08.09.2024 um 17:43 +0800 schrieb 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) {
obj->flags & ETNA_BO_CACHE_MASK
> + 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)
