In order to reach the frequencies needed to output at 594MHz, the firmware needs to be configured with the appropriate parameters in the config.txt file (enable_hdmi_4kp60 and force_turbo).
Let's detect it at bind time, warn the user if we can't, and filter out the relevant modes.
Signed-off-by: Maxime Ripard maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_hdmi.c | 17 +++++++++++++++++ drivers/gpu/drm/vc4/vc4_hdmi.h | 8 ++++++++ 2 files changed, 25 insertions(+)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index b5bc742993a4..f05f6da286f7 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -953,6 +953,9 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder, if (pixel_rate > vc4_hdmi->variant->max_pixel_clock) return -EINVAL;
+ if (vc4_hdmi->disable_4kp60 && (pixel_rate > HDMI_14_MAX_TMDS_CLK)) + return -EINVAL; + vc4_state->pixel_rate = pixel_rate;
return 0; @@ -972,6 +975,9 @@ vc4_hdmi_encoder_mode_valid(struct drm_encoder *encoder, if ((mode->clock * 1000) > vc4_hdmi->variant->max_pixel_clock) return MODE_CLOCK_HIGH;
+ if (vc4_hdmi->disable_4kp60 && ((mode->clock * 1000) > HDMI_14_MAX_TMDS_CLK)) + return MODE_CLOCK_HIGH; + return MODE_OK; }
@@ -1986,6 +1992,17 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data) vc4_hdmi->disable_wifi_frequencies = of_property_read_bool(dev->of_node, "wifi-2.4ghz-coexistence");
+ if (variant->max_pixel_clock == 600000000) { + struct vc4_dev *vc4 = to_vc4_dev(drm); + long max_rate = clk_get_max_rate(vc4->hvs->core_clk); + + if (max_rate < 550000000) { + drm_warn(drm, "The core clock cannot reach frequencies high enough to support 4k @ 60Hz."); + drm_warn(drm, "Please change your config.txt file to add hdmi_enable_4kp60 and force_turbo"); + vc4_hdmi->disable_4kp60 = true; + } + } + if (vc4_hdmi->variant->reset) vc4_hdmi->variant->reset(vc4_hdmi);
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h index 3cebd1fd00fc..3cd021136402 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.h +++ b/drivers/gpu/drm/vc4/vc4_hdmi.h @@ -154,6 +154,14 @@ struct vc4_hdmi { */ bool disable_wifi_frequencies;
+ /* + * Even if HDMI0 on the RPi4 can output modes requiring a pixel + * rate higher than 297MHz, it needs some adjustments in the + * config.txt file to be able to do so and thus won't always be + * available. + */ + bool disable_4kp60; + struct cec_adapter *cec_adap; struct cec_msg cec_rx_msg; bool cec_tx_ok;