drm/amdgpu: Add module param to control SI support

If AMDGPU supports SI, add a module parameter to control SI
support. It's off by default in AMDGPU as long as SI suppost is
experimental, while it is on by default in radeon.

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Acked-by: Michel Dänzer <michel.daenzer@amd.com>

[ Michel Dänzer: Squash in amdgpu_si_support initialization fix ]
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index e0911798e2c2..bd35c83c7c78 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -87,6 +87,23 @@ int amdgpu_driver_load_kms(struct drm_device *dev, unsigned long flags)
         struct amdgpu_device *adev;
         int r, acpi_status;
 
+#ifdef CONFIG_DRM_AMDGPU_SI
+        if (!amdgpu_si_support) {
+                switch (flags & AMD_ASIC_MASK) {
+                case CHIP_TAHITI:
+                case CHIP_PITCAIRN:
+                case CHIP_VERDE:
+                case CHIP_OLAND:
+                case CHIP_HAINAN:
+                        dev_info(dev->dev,
+                                 "SI support provided by radeon.\n");
+                        dev_info(dev->dev,
+                "Use radeon.si_support=0 amdgpu.si_support=1 to override.\n"
+                                );
+                        return -ENODEV;
+                }
+        }
+#endif
 #ifdef CONFIG_DRM_AMDGPU_CIK
         if (!amdgpu_cik_support) {
                 switch (flags & AMD_ASIC_MASK) {