drm/amdgpu: add nbio 6.1 register init function

Used for nbio registers that need to be initialized.  Currently
only used for a golden setting that got missed on some boards.

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/nbio_v6_1.c

@@ -32,6 +32,7 @@
 
 #define smnCPM_CONTROL                                                                                  0x11180460
 #define smnPCIE_CNTL2                                                                                   0x11180070
+#define smnPCIE_CONFIG_CNTL                                                                             0x11180044
 
 u32 nbio_v6_1_get_rev_id(struct amdgpu_device *adev)
 {
@@ -256,3 +257,15 @@ void nbio_v6_1_detect_hw_virt(struct amdgpu_device *adev)
 			adev->virt.caps |= AMDGPU_PASSTHROUGH_MODE;
 	}
 }
+
+void nbio_v6_1_init_registers(struct amdgpu_device *adev)
+{
+	uint32_t def, data;
+
+	def = data = RREG32_PCIE(smnPCIE_CONFIG_CNTL);
+	data = REG_SET_FIELD(data, PCIE_CONFIG_CNTL, CI_SWUS_MAX_READ_REQUEST_SIZE_MODE, 1);
+	data = REG_SET_FIELD(data, PCIE_CONFIG_CNTL, CI_SWUS_MAX_READ_REQUEST_SIZE_PRIV, 1);
+
+	if (def != data)
+		WREG32_PCIE(smnPCIE_CONFIG_CNTL, data);
+}

drivers/gpu/drm/amd/amdgpu/nbio_v6_1.h

@@ -50,5 +50,6 @@ void nbio_v6_1_update_medium_grain_clock_gating(struct amdgpu_device *adev, bool
 void nbio_v6_1_update_medium_grain_light_sleep(struct amdgpu_device *adev, bool enable);
 void nbio_v6_1_get_clockgating_state(struct amdgpu_device *adev, u32 *flags);
 void nbio_v6_1_detect_hw_virt(struct amdgpu_device *adev);
+void nbio_v6_1_init_registers(struct amdgpu_device *adev);
 
 #endif