drm/amdgpu: add VRAM manager v2

Split VRAM allocations into 4MB blocks.

v2: fix typo in comment, some suggested cleanups
v3: document how to disable the feature, fix rebase issue

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Tested-by: Mike Lothian <mike@fireburn.co.uk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 246bbd1ab5ec..9df66d1e843d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -1052,6 +1052,13 @@ static void amdgpu_check_arguments(struct amdgpu_device *adev)
                          amdgpu_vm_block_size);
                 amdgpu_vm_block_size = 9;
         }
+
+        if ((amdgpu_vram_page_split != -1 && amdgpu_vram_page_split < 16) ||
+            !amdgpu_check_pot_argument(amdgpu_vram_page_split)) {
+                dev_warn(adev->dev, "invalid VRAM page split (%d)\n",
+                         amdgpu_vram_page_split);
+                amdgpu_vram_page_split = 1024;
+        }
 }
 
 /**