From 57fb32e632be4d406b4594829e3befdae1100c12 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Thu, 29 Oct 2020 13:25:22 +0100 Subject: [PATCH] drm/vc4: hdmi: Block odd horizontal timings The FIFO between the pixelvalve and the HDMI controller runs at 2 pixels per clock cycle, and cannot deal with odd timings. Let's reject any mode with such timings. Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Link: https://patchwork.freedesktop.org/patch/msgid/20201029122522.1917579-2-maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_hdmi.c | 12 ++++++++++++ drivers/gpu/drm/vc4/vc4_hdmi.h | 3 +++ 2 files changed, 15 insertions(+) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 600dd6d..4689a73 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -768,6 +768,11 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder, struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder); unsigned long long pixel_rate = mode->clock * 1000; + if (vc4_hdmi->variant->unsupported_odd_h_timings && + ((mode->hdisplay % 2) || (mode->hsync_start % 2) || + (mode->hsync_end % 2) || (mode->htotal % 2))) + return -EINVAL; + if (pixel_rate > vc4_hdmi->variant->max_pixel_clock) return -EINVAL; @@ -780,6 +785,11 @@ vc4_hdmi_encoder_mode_valid(struct drm_encoder *encoder, { struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder); + if (vc4_hdmi->variant->unsupported_odd_h_timings && + ((mode->hdisplay % 2) || (mode->hsync_start % 2) || + (mode->hsync_end % 2) || (mode->htotal % 2))) + return MODE_H_ILLEGAL; + if ((mode->clock * 1000) > vc4_hdmi->variant->max_pixel_clock) return MODE_CLOCK_HIGH; @@ -1832,6 +1842,7 @@ static const struct vc4_hdmi_variant bcm2711_hdmi0_variant = { PHY_LANE_2, PHY_LANE_CK, }, + .unsupported_odd_h_timings = true, .init_resources = vc5_hdmi_init_resources, .csc_setup = vc5_hdmi_csc_setup, @@ -1857,6 +1868,7 @@ static const struct vc4_hdmi_variant bcm2711_hdmi1_variant = { PHY_LANE_CK, PHY_LANE_2, }, + .unsupported_odd_h_timings = true, .init_resources = vc5_hdmi_init_resources, .csc_setup = vc5_hdmi_csc_setup, diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h index 63c6f8b..6815e93 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.h +++ b/drivers/gpu/drm/vc4/vc4_hdmi.h @@ -62,6 +62,9 @@ struct vc4_hdmi_variant { */ enum vc4_hdmi_phy_channel phy_lane_mapping[4]; + /* The BCM2711 cannot deal with odd horizontal pixel timings */ + bool unsupported_odd_h_timings; + /* Callback to get the resources (memory region, interrupts, * clocks, etc) for that variant. */ -- 2.7.4