This patch limits the pixel clock to 13.4 MHz - 266 MHz for i.MX6Q and 13.5 MHz - 270 MHz for i.MX6DL, which is the range documented in the HDMI Transmitter chapter of the respective reference manuals.
Without this patch, when connected to a monitor capable of 2160p60 modes, dw_hdmi will happily report this mode and the IPU code will cause a division by zero in ipu_di_config_clock when trying to figure out how to divide the 264 MHz HSP clock down to ~600 MHz.
Signed-off-by: Philipp Zabel p.zabel@pengutronix.de --- drivers/gpu/drm/imx/dw_hdmi-imx.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/imx/dw_hdmi-imx.c b/drivers/gpu/drm/imx/dw_hdmi-imx.c index 121d30c..d25aaef 100644 --- a/drivers/gpu/drm/imx/dw_hdmi-imx.c +++ b/drivers/gpu/drm/imx/dw_hdmi-imx.c @@ -136,11 +136,34 @@ static struct drm_encoder_funcs dw_hdmi_imx_encoder_funcs = { .destroy = drm_encoder_cleanup, };
+static enum drm_mode_status imx6q_hdmi_mode_valid(struct drm_connector *con, + struct drm_display_mode *mode) +{ + if (mode->clock < 13500) + return MODE_CLOCK_LOW; + if (mode->clock > 266000) + return MODE_CLOCK_HIGH; + + return MODE_OK; +} + +static enum drm_mode_status imx6dl_hdmi_mode_valid(struct drm_connector *con, + struct drm_display_mode *mode) +{ + if (mode->clock < 13500) + return MODE_CLOCK_LOW; + if (mode->clock > 270000) + return MODE_CLOCK_HIGH; + + return MODE_OK; +} + static struct dw_hdmi_plat_data imx6q_hdmi_drv_data = { - .mpll_cfg = imx_mpll_cfg, - .cur_ctr = imx_cur_ctr, - .sym_term = imx_sym_term, - .dev_type = IMX6Q_HDMI, + .mpll_cfg = imx_mpll_cfg, + .cur_ctr = imx_cur_ctr, + .sym_term = imx_sym_term, + .dev_type = IMX6Q_HDMI, + .mode_valid = imx6q_hdmi_mode_valid, };
static struct dw_hdmi_plat_data imx6dl_hdmi_drv_data = { @@ -148,6 +171,7 @@ static struct dw_hdmi_plat_data imx6dl_hdmi_drv_data = { .cur_ctr = imx_cur_ctr, .sym_term = imx_sym_term, .dev_type = IMX6DL_HDMI, + .mode_valid = imx6dl_hdmi_mode_valid, };
static const struct of_device_id dw_hdmi_imx_dt_ids[] = {