<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <style type="text/css" style="display:none;"></style> </head> <body dir="ltr"> <div id="divtagdefaultwrapper" style="font-size:12pt;color:#000000;font-family:Calibri,Helvetica,sans-serif;" dir="ltr"> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> </div> <hr style="display:inline-block;width:98%" tabindex="-1"> <div id="divRplyFwdMsg" dir="ltr">From: amd-gfx <amd-gfx-bounces@lists.freedesktop.org> on behalf of Harry Wentland <harry.wentland@amd.com> Sent: Tuesday, May 8, 2018 11:33:42 AM To: amd-gfx@lists.freedesktop.org; Deucher, Alexander Cc: Wentland, Harry Subject: [PATCH v3] drm/amdgpu: Don't default to DC support for Kaveri and older <div> </div> </div> <div class="BodyFragment"> <div class="PlainText">We've had a number of users report failures to detect and light up display with DC with LVDS and VGA. These connector types are not currently supported with DC. I'd like to add support but unfortunately don't have a system with LVDS or VGA available. In order not to cause regressions we should probably fallback to the non-DC driver for ASICs that support VGA and LVDS. These ASICs are: * Bonaire * Kabini * Kaveri * Mullins ASIC support can always be force enabled with amdgpu.dc=1 v2: Keep Hawaii on DC v3: Added Mullins to the list Signed-off-by: Harry Wentland <harry.wentland@amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index 887f7c9e84e0..f3ed4950d129 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -2141,10 +2141,18 @@ bool amdgpu_device_asic_has_dc_support(enum amd_asic_type asic_type) switch (asic_type) { #if defined(CONFIG_DRM_AMD_DC) case CHIP_BONAIRE: - case CHIP_HAWAII: case CHIP_KAVERI: case CHIP_KABINI: case CHIP_MULLINS: + /* + * 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. + */ + return amdgpu_dc > 0; + case CHIP_HAWAII: case CHIP_CARRIZO: case CHIP_STONEY: case CHIP_POLARIS10: -- 2.17.0 _______________________________________________ amd-gfx mailing list amd-gfx@lists.freedesktop.org <a href="https://lists.freedesktop.org/mailman/listinfo/amd-gfx">https://lists.freedesktop.org/mailman/listinfo/amd-gfx</a> </div> </div> </body> </html>