drm/amdgpu: Use DC by default on SI dGPUs

Now that DC supports analog connectors, it has reached feature
parity with the legacy non-DC display driver on SI dGPUs.
Use the DC display driver by default on SI dGPUs, unless it is
explicitly disabled using the amdgpu.dc=0 module parameter.

DC brings proper support for DP/HDMI audio, DP MST,
10-bit colors, some HDR features, atomic modesetting, etc.

Also clarify the comment about what is missing to have full
DC support for CIK APUs.

Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 86255c13fbb79295b8896a4841cfea1117a03f21..bfbf874a10008e4d871e4e7da8d1b8d4fb02f862 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4249,24 +4249,13 @@ bool amdgpu_device_asic_has_dc_support(struct pci_dev *pdev,
        case CHIP_PITCAIRN:
        case CHIP_VERDE:
        case CHIP_OLAND:
-               /*
-                * We have systems in the wild with these ASICs that require
-                * LVDS and VGA support which is not supported with DC.
-                *
-                * Fallback to the non-DC driver here by default so as not to
-                * cause regressions.
-                */
-#if defined(CONFIG_DRM_AMD_DC_SI)
-               return amdgpu_dc > 0;
-#else
-               return false;
-#endif
+               return amdgpu_dc != 0 && IS_ENABLED(CONFIG_DRM_AMD_DC_SI);
        case CHIP_KAVERI:
        case CHIP_KABINI:
        case CHIP_MULLINS:
                /*
                 * We have systems in the wild with these ASICs that require
-                * VGA support which is not supported with DC.
+                * TRAVIS and NUTMEG support which is not supported with DC.
                 *
                 * Fallback to the non-DC driver here by default so as not to
                 * cause regressions.