It seems like the mixer can only run properly when clocked at 150MHz. In order to have something more robust than simply a fire-and-forget assigned-clocks-rate, let's put that in the code.
Reviewed-by: Chen-Yu Tsai wens@csie.org Signed-off-by: Maxime Ripard maxime.ripard@free-electrons.com --- drivers/gpu/drm/sun4i/sun8i_mixer.c | 10 ++++++++++ drivers/gpu/drm/sun4i/sun8i_mixer.h | 3 +++ 2 files changed, 13 insertions(+)
diff --git a/drivers/gpu/drm/sun4i/sun8i_mixer.c b/drivers/gpu/drm/sun4i/sun8i_mixer.c index 29ceeb016d72..3a610a87cbd2 100644 --- a/drivers/gpu/drm/sun4i/sun8i_mixer.c +++ b/drivers/gpu/drm/sun4i/sun8i_mixer.c @@ -398,6 +398,15 @@ static int sun8i_mixer_bind(struct device *dev, struct device *master, ret = PTR_ERR(mixer->mod_clk); goto err_disable_bus_clk; } + + /* + * It seems that we need to enforce that rate for whatever + * reason for the mixer to be functional. Make sure it's the + * case. + */ + if (mixer->cfg->mod_rate) + clk_set_rate(mixer->mod_clk, mixer->cfg->mod_rate); + clk_prepare_enable(mixer->mod_clk);
list_add_tail(&mixer->engine.list, &drv->engine_list); @@ -474,6 +483,7 @@ static const struct sun8i_mixer_cfg sun8i_v3s_mixer_cfg = { .ui_num = 1, .scaler_mask = 0x3, .ccsc = 0, + .mod_rate = 150000000, };
static const struct of_device_id sun8i_mixer_of_table[] = { diff --git a/drivers/gpu/drm/sun4i/sun8i_mixer.h b/drivers/gpu/drm/sun4i/sun8i_mixer.h index bc58040a88f9..f34e70c42adf 100644 --- a/drivers/gpu/drm/sun4i/sun8i_mixer.h +++ b/drivers/gpu/drm/sun4i/sun8i_mixer.h @@ -121,12 +121,15 @@ struct de2_fmt_info { * Set value to 0 if this is first mixer or second mixer with VEP support. * Set value to 1 if this is second mixer without VEP support. Other values * are invalid. + * @mod_rate: module clock rate that needs to be set in order to have + * a functional block. */ struct sun8i_mixer_cfg { int vi_num; int ui_num; int scaler_mask; int ccsc; + unsigned long mod_rate; };
struct sun8i_mixer {