drm/amdgpu: add helper to query rlcg reg access flag

Query rlc indirect register access approach specified
by sriov host driver per ip blocks
Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Zhou, Peng Ju <PengJu.Zhou@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -820,3 +820,38 @@ void amdgpu_virt_update_sriov_video_codec(struct amdgpu_device *adev,
 		}
 	}
 }
+
+bool amdgpu_virt_get_rlcg_reg_access_flag(struct amdgpu_device *adev, u32 acc_flags,
+					  u32 hwip, bool write, u32 *rlcg_flag)
+{
+	bool ret = false;
+
+	switch (hwip) {
+	case GC_HWIP:
+		if (amdgpu_sriov_reg_indirect_gc(adev)) {
+			*rlcg_flag =
+				write ? AMDGPU_RLCG_GC_WRITE : AMDGPU_RLCG_GC_READ;
+			ret = true;
+		/* only in new version, AMDGPU_REGS_NO_KIQ and
+		 * AMDGPU_REGS_RLC are enabled simultaneously */
+		} else if ((acc_flags & AMDGPU_REGS_RLC) &&
+			   !(acc_flags & AMDGPU_REGS_NO_KIQ)) {
+			*rlcg_flag = AMDGPU_RLCG_GC_WRITE_LEGACY;
+			ret = true;
+		}
+		break;
+	case MMHUB_HWIP:
+		if (amdgpu_sriov_reg_indirect_mmhub(adev) &&
+		    (acc_flags & AMDGPU_REGS_RLC) && write) {
+			*rlcg_flag = AMDGPU_RLCG_MMHUB_WRITE;
+			ret = true;
+		}
+		break;
+	default:
+		dev_err(adev->dev,
+			"indirect registers access through rlcg is not supported\n");
+		ret = false;
+		break;
+	}
+	return ret;
+}

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

@@ -32,6 +32,12 @@
 #define AMDGPU_PASSTHROUGH_MODE        (1 << 3) /* thw whole GPU is pass through for VM */
 #define AMDGPU_SRIOV_CAPS_RUNTIME      (1 << 4) /* is out of full access mode */
 
+/* flags for indirect register access path supported by rlcg for sriov */
+#define AMDGPU_RLCG_GC_WRITE_LEGACY    (0x8 << 28)
+#define AMDGPU_RLCG_GC_WRITE           (0x0 << 28)
+#define AMDGPU_RLCG_GC_READ            (0x1 << 28)
+#define AMDGPU_RLCG_MMHUB_WRITE        (0x2 << 28)
+
 /* all asic after AI use this offset */
 #define mmRCC_IOV_FUNC_IDENTIFIER 0xDE5
 /* tonga/fiji use this offset */
@@ -321,4 +327,6 @@ enum amdgpu_sriov_vf_mode amdgpu_virt_get_sriov_vf_mode(struct amdgpu_device *ad
 void amdgpu_virt_update_sriov_video_codec(struct amdgpu_device *adev,
 			struct amdgpu_video_codec_info *encode, uint32_t encode_array_size,
 			struct amdgpu_video_codec_info *decode, uint32_t decode_array_size);
+bool amdgpu_virt_get_rlcg_reg_access_flag(struct amdgpu_device *adev, u32 acc_flags,
+					  u32 hwip, bool write, u32 *rlcg_flag);
 #endif