Am 10.05.22 um 17:20 schrieb Arunpravin Paneer Selvam:
Hi Christian,
On 5/10/2022 5:06 PM, Christian König wrote:
We still need to calculate a virtual start address for the resource to
aid checking of it is visible or not.
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 22 +++++++++++++-------
1 file changed, 14 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
index 49e4092f447f..51d9d3a4456c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
@@ -496,16 +496,22 @@ static int amdgpu_vram_mgr_new(struct
ttm_resource_manager *man,
list_splice_tail(trim_list, &vres->blocks);
}
- list_for_each_entry(block, &vres->blocks, link)
- vis_usage += amdgpu_vram_mgr_vis_size(adev, block);
+ vres->base.start = 0;
+ list_for_each_entry(block, &vres->blocks, link) {
+ unsigned long start;
- block = amdgpu_vram_mgr_first_block(&vres->blocks);
- if (!block) {
- r = -EINVAL;
- goto error_fini;
- }
+ start = amdgpu_vram_mgr_block_start(block) +
+ amdgpu_vram_mgr_block_size(block);
+ start >>= PAGE_SHIFT;
- vres->base.start = amdgpu_vram_mgr_block_start(block) >>
PAGE_SHIFT;
+ if (start > vres->base.num_pages)
+ start -= vres->base.num_pages;
I think this works for continuous blocks of addresses, but for a non
continuous blocks allocated at different
locations and linked together using list, this might fetch an invalid
address. I will check this patch on my
setup and inform you.
It indeed does fetch an invalid address and that is perfectly expected
behavior.
See the resource->start value for non-contiguous allocations is just the
maximum allocated address.
This makes it possible to easily check if a buffer is inside the CPU
accessible VRAM window or not.
As I said we should probably get rid of that, but for now it's necessary.
Regards,
Christian.
Regards,
Arun
+ else
+ start = 0;
+ vres->base.start = max(vres->base.start, start);
+
+ vis_usage += amdgpu_vram_mgr_vis_size(adev, block);
+ }
if (amdgpu_is_vram_mgr_blocks_contiguous(&vres->blocks))
vres->base.placement |= TTM_PL_FLAG_CONTIGUOUS;
