drm/amdgpu: Add pci replay count to nbio v7.9

Add implementation to get pcie replay count for nbio v7.9.

Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/nbio_v7_9.c

@@ -32,6 +32,9 @@
 
 #define NPS_MODE_MASK 0x000000FFL
 
+/* Core 0 Port 0 counter */
+#define smnPCIEP_NAK_COUNTER 0x1A340218
+
 static void nbio_v7_9_remap_hdp_registers(struct amdgpu_device *adev)
 {
 	WREG32_SOC15(NBIO, 0, regBIF_BX0_REMAP_HDP_MEM_FLUSH_CNTL,
@@ -427,6 +430,22 @@ static void nbio_v7_9_init_registers(struct amdgpu_device *adev)
 	}
 }
 
+static u64 nbio_v7_9_get_pcie_replay_count(struct amdgpu_device *adev)
+{
+	u32 val, nak_r, nak_g;
+
+	if (adev->flags & AMD_IS_APU)
+		return 0;
+
+	/* Get the number of NAKs received and generated */
+	val = RREG32_PCIE(smnPCIEP_NAK_COUNTER);
+	nak_r = val & 0xFFFF;
+	nak_g = val >> 16;
+
+	/* Add the total number of NAKs, i.e the number of replays */
+	return (nak_r + nak_g);
+}
+
 const struct amdgpu_nbio_funcs nbio_v7_9_funcs = {
 	.get_hdp_flush_req_offset = nbio_v7_9_get_hdp_flush_req_offset,
 	.get_hdp_flush_done_offset = nbio_v7_9_get_hdp_flush_done_offset,
@@ -450,4 +469,5 @@ const struct amdgpu_nbio_funcs nbio_v7_9_funcs = {
 	.get_compute_partition_mode = nbio_v7_9_get_compute_partition_mode,
 	.get_memory_partition_mode = nbio_v7_9_get_memory_partition_mode,
 	.init_registers = nbio_v7_9_init_registers,
+	.get_pcie_replay_count = nbio_v7_9_get_pcie_replay_count,
 };

drivers/gpu/drm/amd/amdgpu/soc15.c

@@ -895,7 +895,7 @@ static const struct amdgpu_asic_funcs aqua_vanjaram_asic_funcs =
 	.init_doorbell_index = &aqua_vanjaram_doorbell_index_init,
 	.get_pcie_usage = &vega20_get_pcie_usage,
 	.need_reset_on_init = &soc15_need_reset_on_init,
-	.get_pcie_replay_count = &soc15_get_pcie_replay_count,
+	.get_pcie_replay_count = &amdgpu_nbio_get_pcie_replay_count,
 	.supports_baco = &soc15_supports_baco,
 	.pre_asic_init = &soc15_pre_asic_init,
 	.query_video_codecs = &soc15_query_video_codecs,