From: John Brooks <john@xxxxxxxxxxxxx>
Allow specifying a limit on visible VRAM via a module parameter. This is
helpful for testing performance under visible VRAM pressure.
v2: Add cast to 64-bit (Christian König)
Signed-off-by: John Brooks <john at fastquake.com>
Reviewed-by: Michel Dänzer <michel.daenzer at amd.com>
Reviewed-by: Christian König <christian.koenig at amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 +
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 ++++
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 8 ++++++++
3 files changed, 13 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 8b4e8ed9e9dc..b95c1074d42c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -75,6 +75,7 @@
*/
extern int amdgpu_modeset;
extern int amdgpu_vram_limit;
+extern int amdgpu_vis_vram_limit;
extern int amdgpu_gart_size;
extern int amdgpu_moverate;
extern int amdgpu_benchmarking;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 271c9d528af6..72ff7223447e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -74,6 +74,7 @@
#define KMS_DRIVER_PATCHLEVEL 0
int amdgpu_vram_limit = 0;
+int amdgpu_vis_vram_limit = 0;
int amdgpu_gart_size = -1; /* auto */
int amdgpu_moverate = -1; /* auto */
int amdgpu_benchmarking = 0;
@@ -121,6 +122,9 @@ int amdgpu_lbpw = -1;
MODULE_PARM_DESC(vramlimit, "Restrict VRAM for testing, in megabytes");
module_param_named(vramlimit, amdgpu_vram_limit, int, 0600);
+MODULE_PARM_DESC(vis_vramlimit, "Restrict visible VRAM for testing, in megabytes");
+module_param_named(vis_vramlimit, amdgpu_vis_vram_limit, int, 0444);
+
MODULE_PARM_DESC(gartsize, "Size of PCIE/IGP gart to setup in megabytes (32, 64, etc., -1 = auto)");
module_param_named(gartsize, amdgpu_gart_size, int, 0600);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index a81c4e5e9f6b..9d4861aea18a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1092,6 +1092,7 @@ static struct ttm_bo_driver amdgpu_bo_driver = {
int amdgpu_ttm_init(struct amdgpu_device *adev)
{
int r;
+ u64 vis_vram_limit;
r = amdgpu_ttm_global_init(adev);
if (r) {
@@ -1115,6 +1116,13 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
DRM_ERROR("Failed initializing VRAM heap.\n");
return r;
}
+
+ /* Reduce size of CPU-visible VRAM if requested */
+ vis_vram_limit = (u64)amdgpu_vis_vram_limit * 1024 * 1024;
+ if (amdgpu_vis_vram_limit > 0 &&
+ vis_vram_limit <= adev->mc.visible_vram_size)
+ adev->mc.visible_vram_size = vis_vram_limit;
+
/* Change the size here instead of the init above so only lpfn is affected */
amdgpu_ttm_set_active_vram_size(adev, adev->mc.visible_vram_size);
--
2.13.2
