drm/vc4: hdmi: Take into account the clock doubling flag in atomic_check

Commit 63495f6b4aed ("drm/vc4: hdmi: Make sure our clock rate is within
limits") was intended to compute the pixel rate to make sure we remain
within the boundaries of what the hardware can provide.

However, unlike what mode_valid was checking for, we forgot to take
into account the clock doubling flag that can be set for modes. Let's
honor that flag if it's there.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reported-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Fixes: 63495f6b4aed ("drm/vc4: hdmi: Make sure our clock rate is within limits")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215154243.540115-4-maxime@cerno.tech

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 8ce5dd65f6e4a6cbabd25f111222986b41ebf719..3dac839b0fa5a51916c115f2a380275d4893b543 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -799,6 +799,9 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
                pixel_rate = mode->clock * 1000;
        }
 
+       if (mode->flags & DRM_MODE_FLAG_DBLCLK)
+               pixel_rate = pixel_rate * 2;
+
        if (pixel_rate > vc4_hdmi->variant->max_pixel_clock)
                return -EINVAL;