From 06a0e398e7dcd6ba0a61713596c32ec6d43b47c8 Mon Sep 17 00:00:00 2001 From: Dave Stevenson Date: Tue, 18 Jun 2019 21:37:45 +0100 Subject: [PATCH] drm/vc4: Limit fkms to modes <= 85Hz Selecting 1080p100 and 120 has very limited gain, but don't want to block VGA85 and similar. Signed-off-by: Dave Stevenson --- drivers/gpu/drm/vc4/vc4_firmware_kms.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/gpu/drm/vc4/vc4_firmware_kms.c +++ b/drivers/gpu/drm/vc4/vc4_firmware_kms.c @@ -822,6 +822,10 @@ vc4_crtc_mode_valid(struct drm_crtc *crt return MODE_NO_DBLESCAN; } + /* Disable refresh rates > 85Hz as limited gain from them */ + if (drm_mode_vrefresh(mode) > 85) + return MODE_BAD_VVALUE; + /* Limit the pixel clock based on the HDMI clock limits from the * firmware */