If the size returned by drm buddy allocator is higher than the required size, we take the higher size to calculate the buffer start address. This is required if we couldn't trim the buffer to the requested size. This will fix the display corruption issue on APU's which has limited VRAM size. gitlab issue link: https://gitlab.freedesktop.org/drm/amd/-/issues/2859 JIRA ticket link: https://ontrack-internal.amd.com/browse/SWDEV-425461 Fixes: 0a1844bf0b53 ("drm/buddy: Improve contiguous memory allocation") Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@xxxxxxx> --- drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c index 18f58efc9dc7..08916538a615 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c @@ -77,7 +77,16 @@ static inline bool amdgpu_is_vram_mgr_blocks_contiguous(struct list_head *head) return true; } +static inline u64 amdgpu_vram_mgr_blocks_size(struct list_head *head) +{ + struct drm_buddy_block *block; + u64 size = 0; + list_for_each_entry(block, head, link) + size += amdgpu_vram_mgr_block_size(block); + + return size; +} /** * DOC: mem_info_vram_total @@ -516,6 +525,8 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man, mutex_unlock(&mgr->lock); vres->base.start = 0; + size = max_t(u64, amdgpu_vram_mgr_blocks_size(&vres->blocks), + vres->base.size); list_for_each_entry(block, &vres->blocks, link) { unsigned long start; @@ -523,8 +534,8 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man, amdgpu_vram_mgr_block_size(block); start >>= PAGE_SHIFT; - if (start > PFN_UP(vres->base.size)) - start -= PFN_UP(vres->base.size); + if (start > PFN_UP(size)) + start -= PFN_UP(size); else start = 0; vres->base.start = max(vres->base.start, start); -- 2.25.1