Am 13.04.23 um 16:22 schrieb Bas Nieuwenhuizen:
This info would be used by radv to figure out when we need to
split a submission into multiple submissions. radv currently has
a limit of 192 which seems to work for most gfx submissions, but
is way too high for e.g. compute or sdma.
Userspace is available at
https://gitlab.freedesktop.org/bnieuwenhuizen/mesa/-/commits/ib-rejection-v3
v3: Completely rewrote based on suggestion of making it a separate query.
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2498
Signed-off-by: Bas Nieuwenhuizen <bas@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 9 +++++++++
include/uapi/drm/amdgpu_drm.h | 2 ++
2 files changed, 11 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index 0efb38539d70..1a2e342af1c0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -1140,6 +1140,15 @@ int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
kfree(caps);
return r;
}
+ case AMDGPU_INFO_MAX_IBS: {
+ uint32_t max_ibs[AMDGPU_HW_IP_NUM];
+
+ for (i = 0; i < AMDGPU_HW_IP_NUM; ++i)
+ max_ibs[i] = amdgpu_ring_max_ibs(i);
+
+ return copy_to_user(out, max_ibs,
+ min((size_t)size, sizeof(max_ibs))) ? -EFAULT : 0;
+ }
default:
DRM_DEBUG_KMS("Invalid request %d\n", info->query);
return -EINVAL;
diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
index b6eb90df5d05..6981e59a9401 100644
--- a/include/uapi/drm/amdgpu_drm.h
+++ b/include/uapi/drm/amdgpu_drm.h
@@ -876,6 +876,8 @@ struct drm_amdgpu_cs_chunk_data {
#define AMDGPU_INFO_VIDEO_CAPS_DECODE 0
/* Subquery id: Encode */
#define AMDGPU_INFO_VIDEO_CAPS_ENCODE 1
+/* Query the max number of IBs per gang per submission */
+#define AMDGPU_INFO_MAX_IBS 0x22
#define AMDGPU_INFO_MMR_SE_INDEX_SHIFT 0
#define AMDGPU_INFO_MMR_SE_INDEX_MASK 0xff
