Commit 95a16160 authored by Arunpravin Paneer Selvam's avatar Arunpravin Paneer Selvam Committed by Christian König
Browse files

drm/amdgpu: Reset the clear flag in buddy during resume 



- Added a handler in DRM buddy manager to reset the cleared
  flag for the blocks in the freelist.

- This is necessary because, upon resuming, the VRAM becomes
  cluttered with BIOS data, yet the VRAM backend manager
  believes that everything has been cleared.

v2:
  - Add lock before accessing drm_buddy_clear_reset_blocks()(Matthew Auld)
  - Force merge the two dirty blocks.(Matthew Auld)
  - Add a new unit test case for this issue.(Matthew Auld)
  - Having this function being able to flip the state either way would be
    good. (Matthew Brost)

v3(Matthew Auld):
  - Do merge step first to avoid the use of extra reset flag.

Signed-off-by: default avatarArunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Suggested-by: default avatarChristian König <christian.koenig@amd.com>
Acked-by: default avatarChristian König <christian.koenig@amd.com>
Reviewed-by: default avatarMatthew Auld <matthew.auld@intel.com>
Cc: stable@vger.kernel.org
Fixes: a68c7eaa ("drm/amdgpu: Enable clear page functionality")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3812


Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20250716075125.240637-2-Arunpravin.PaneerSelvam@amd.com
parent cb345f95

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

+2 −0
Original line number Diff line number Diff line
@@ -5193,6 +5193,8 @@ int amdgpu_device_resume(struct drm_device *dev, bool notify_clients) 
		dev->dev->power.disable_depth--;

#endif

	}



	amdgpu_vram_mgr_clear_reset_blocks(adev);

	adev->in_suspend = false;



	if (amdgpu_acpi_smart_shift_update(dev, AMDGPU_SS_DEV_D0))

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h

+1 −0
Original line number Diff line number Diff line
@@ -154,6 +154,7 @@ int amdgpu_vram_mgr_reserve_range(struct amdgpu_vram_mgr *mgr, 
				  uint64_t start, uint64_t size);

int amdgpu_vram_mgr_query_page_status(struct amdgpu_vram_mgr *mgr,

				      uint64_t start);

void amdgpu_vram_mgr_clear_reset_blocks(struct amdgpu_device *adev);



bool amdgpu_res_cpu_visible(struct amdgpu_device *adev,

			    struct ttm_resource *res);

drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c

+17 −0
Original line number Diff line number Diff line
@@ -782,6 +782,23 @@ uint64_t amdgpu_vram_mgr_vis_usage(struct amdgpu_vram_mgr *mgr) 
	return atomic64_read(&mgr->vis_usage);

}



/**

 * amdgpu_vram_mgr_clear_reset_blocks - reset clear blocks

 *

 * @adev: amdgpu device pointer

 *

 * Reset the cleared drm buddy blocks.

 */

void amdgpu_vram_mgr_clear_reset_blocks(struct amdgpu_device *adev)

{

	struct amdgpu_vram_mgr *mgr = &adev->mman.vram_mgr;

	struct drm_buddy *mm = &mgr->mm;



	mutex_lock(&mgr->lock);

	drm_buddy_reset_clear(mm, false);

	mutex_unlock(&mgr->lock);

}



/**

 * amdgpu_vram_mgr_intersects - test each drm buddy block for intersection

 *

drivers/gpu/drm/drm_buddy.c

+43 −0
Original line number Diff line number Diff line
@@ -404,6 +404,49 @@ drm_get_buddy(struct drm_buddy_block *block) 
}

EXPORT_SYMBOL(drm_get_buddy);



/**

 * drm_buddy_reset_clear - reset blocks clear state

 *

 * @mm: DRM buddy manager

 * @is_clear: blocks clear state

 *

 * Reset the clear state based on @is_clear value for each block

 * in the freelist.

 */

void drm_buddy_reset_clear(struct drm_buddy *mm, bool is_clear)

{

	u64 root_size, size, start;

	unsigned int order;

	int i;



	size = mm->size;

	for (i = 0; i < mm->n_roots; ++i) {

		order = ilog2(size) - ilog2(mm->chunk_size);

		start = drm_buddy_block_offset(mm->roots[i]);

		__force_merge(mm, start, start + size, order);



		root_size = mm->chunk_size << order;

		size -= root_size;

	}



	for (i = 0; i <= mm->max_order; ++i) {

		struct drm_buddy_block *block;



		list_for_each_entry_reverse(block, &mm->free_list[i], link) {

			if (is_clear != drm_buddy_block_is_clear(block)) {

				if (is_clear) {

					mark_cleared(block);

					mm->clear_avail += drm_buddy_block_size(mm, block);

				} else {

					clear_reset(block);

					mm->clear_avail -= drm_buddy_block_size(mm, block);

				}

			}

		}

	}

}

EXPORT_SYMBOL(drm_buddy_reset_clear);



/**

 * drm_buddy_free_block - free a block

 *

include/drm/drm_buddy.h

+2 −0
Original line number Diff line number Diff line
@@ -160,6 +160,8 @@ int drm_buddy_block_trim(struct drm_buddy *mm, 
			 u64 new_size,

			 struct list_head *blocks);



void drm_buddy_reset_clear(struct drm_buddy *mm, bool is_clear);



void drm_buddy_free_block(struct drm_buddy *mm, struct drm_buddy_block *block);



void drm_buddy_free_list(struct drm_buddy *mm,