[AMD Official Use Only]
Reviewed-by: Evan Quan <evan.quan@xxxxxxx>
> -----Original Message-----
> From: amd-gfx <amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Alex
> Deucher
> Sent: Thursday, November 4, 2021 11:26 AM
> To: amd-gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>
> Subject: [PATCH] drm/amdgpu: fix SI handling in
> amdgpu_device_asic_has_dc_support()
>
> Properly handle SI DC support when CONFIG_DRM_AMD_DC_SI is not
> set.
>
> Fixes: f7f12b25823c0d ("drm/amdgpu: default to true in
> amdgpu_device_asic_has_dc_support")
> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 95fec36e385e..db3728a11481 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -3166,11 +3166,21 @@ bool
> amdgpu_device_asic_has_dc_support(enum amd_asic_type asic_type)
> {
> switch (asic_type) {
> #if defined(CONFIG_DRM_AMD_DC)
> -#if defined(CONFIG_DRM_AMD_DC_SI)
> case CHIP_TAHITI:
> 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
> case CHIP_BONAIRE:
> case CHIP_KAVERI:
> --
> 2.31.1
