[PATCH 11/14] drm/amdgpu: add AMDGPU_INFO_DOORBELL

["David (Ming Qiang) Wu" <David.Wu3@amd.com>]

Use it to get the doorbell range and aggregated doorbell
enablement and offset. This patch only supports VCN for now.

V2 - drop VPE and use vcn.agdb_offset saved in
     umsch_mm_agdb_index_init() (suggested by Alex)

Signed-off-by: David (Ming Qiang) Wu <David.Wu3@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 18 ++++++++++++++++++
 include/uapi/drm/amdgpu_drm.h           | 13 +++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index f512b6ec6c53..1b935d285053 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -1425,6 +1425,24 @@ int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 			return -EINVAL;
 		}
 	}
+	case AMDGPU_INFO_DOORBELL: {
+		struct drm_amdgpu_info_doorbell doorbell_info = {};
+		/* note: may need to check asic_type */
+		switch (info->query_hw_ip.type) {
+		case AMDGPU_HW_IP_VCN_ENC:
+			if (adev->agdb_bo) {
+				doorbell_info.agdb_enable = 1;
+				doorbell_info.agdb_offset = adev->vcn.agdb_offset;
+			}
+			doorbell_info.index_start = adev->doorbell_index.vcn.vcn_ring0_1 << 1;
+			doorbell_info.index_end = (adev->doorbell_index.vcn.vcn_ring6_7 << 1) + 1;
+			break;
+		default:
+			return -EINVAL;
+		}
+		return copy_to_user(out, &doorbell_info,
+				    min((size_t)size, sizeof(doorbell_info))) ? -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 3e7c12d5987f..902201303700 100644
--- a/include/uapi/drm/amdgpu_drm.h
+++ b/include/uapi/drm/amdgpu_drm.h
@@ -1279,6 +1279,8 @@ struct drm_amdgpu_cs_chunk_cp_gfx_shadow {
 #define AMDGPU_INFO_GPUVM_FAULT			0x23
 /* query FW object size and alignment */
 #define AMDGPU_INFO_UQ_FW_AREAS			0x24
+/* query doorbell info */
+#define AMDGPU_INFO_DOORBELL			0x25
 
 #define AMDGPU_INFO_MMR_SE_INDEX_SHIFT	0
 #define AMDGPU_INFO_MMR_SE_INDEX_MASK	0xff
@@ -1688,6 +1690,17 @@ struct drm_color_ctm_3x4 {
 	__u64 matrix[12];
 };
 
+/* for AMDGPU_INFO_DOORBELL query */
+struct drm_amdgpu_info_doorbell {
+	__u32 index_start;
+	/* could be equal to index_start */
+	__u32 index_end;
+	/* aggregated doorbell, 0 for disable */
+	__u32 agdb_enable;
+	/* if agdb_enable, it is a value in [index_start, index_end] */
+	__u32 agdb_offset;
+};
+
 #if defined(__cplusplus)
 }
 #endif
-- 
2.43.0