drm/amd/amdgpu: Add pcie indirect support to amdgpu_mm_wreg_mmio_rlc()

The function amdgpu_mm_wreg_mmio_rlc() is used by debugfs to write to
MMIO registers.  It didn't support registers beyond the BAR mapped MMIO
space.  This adds pcie indirect write support.
Signed-off-by: NTom St Denis <tom.stdenis@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

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

@@ -552,7 +552,7 @@ void amdgpu_device_wreg(struct amdgpu_device *adev,
 }
 
 /**
- * amdgpu_mm_wreg_mmio_rlc -  write register either with mmio or with RLC path if in range
+ * amdgpu_mm_wreg_mmio_rlc -  write register either with direct/indirect mmio or with RLC path if in range
  *
  * this function is invoked only the debugfs register access
  */
@@ -567,6 +567,8 @@ void amdgpu_mm_wreg_mmio_rlc(struct amdgpu_device *adev,
 	    adev->gfx.rlc.funcs->is_rlcg_access_range) {
 		if (adev->gfx.rlc.funcs->is_rlcg_access_range(adev, reg))
 			return adev->gfx.rlc.funcs->sriov_wreg(adev, reg, v, 0, 0);
+	} else if ((reg * 4) >= adev->rmmio_size) {
+		adev->pcie_wreg(adev, reg * 4, v);
 	} else {
 		writel(v, ((void __iomem *)adev->rmmio) + (reg * 4));
 	}