If the firmware hadn't brought up HDMI for us, we need to do its power-on reset sequence (reset HD and and clear its STANDBY bits, reset HDMI, and leave the PHY disabled).
Signed-off-by: Eric Anholt eric@anholt.net --- drivers/gpu/drm/vc4/vc4_hdmi.c | 29 ++++++++++++++++++++++++++++- drivers/gpu/drm/vc4/vc4_regs.h | 2 ++ 2 files changed, 30 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index c49cb44..d189906 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -497,6 +497,16 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data) goto err_put_i2c; }
+ /* This is the rate that is set by the firmware. The number + * needs to be a bit higher than the pixel clock rate + * (generally 148.5Mhz). + */ + ret = clk_set_rate(hdmi->hsm_clock, 163682864); + if (ret) { + DRM_ERROR("Failed to set HSM clock rate: %d\n", ret); + goto err_unprepare_pix; + } + ret = clk_prepare_enable(hdmi->hsm_clock); if (ret) { DRM_ERROR("Failed to turn on HDMI state machine clock: %d\n", @@ -518,7 +528,24 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data) vc4->hdmi = hdmi;
/* HDMI core must be enabled. */ - WARN_ON_ONCE((HD_READ(VC4_HD_M_CTL) & VC4_HD_M_ENABLE) == 0); + if (!(HD_READ(VC4_HD_M_CTL) & VC4_HD_M_ENABLE)) { + HD_WRITE(VC4_HD_M_CTL, VC4_HD_M_SW_RST); + udelay(1); + HD_WRITE(VC4_HD_M_CTL, 0); + + HD_WRITE(VC4_HD_M_CTL, VC4_HD_M_ENABLE); + + HDMI_WRITE(VC4_HDMI_SW_RESET_CONTROL, + VC4_HDMI_SW_RESET_HDMI | + VC4_HDMI_SW_RESET_FORMAT_DETECT); + + HDMI_WRITE(VC4_HDMI_SW_RESET_CONTROL, 0); + + /* PHY should be in reset, like + * vc4_hdmi_encoder_disable() does. + */ + HDMI_WRITE(VC4_HDMI_TX_PHY_RESET_CTL, 0xf << 16); + }
drm_encoder_init(drm, hdmi->encoder, &vc4_hdmi_encoder_funcs, DRM_MODE_ENCODER_TMDS, NULL); diff --git a/drivers/gpu/drm/vc4/vc4_regs.h b/drivers/gpu/drm/vc4/vc4_regs.h index 25df20e..31042a4 100644 --- a/drivers/gpu/drm/vc4/vc4_regs.h +++ b/drivers/gpu/drm/vc4/vc4_regs.h @@ -456,6 +456,8 @@ #define VC4_HDMI_TX_PHY_RESET_CTL 0x2c0
#define VC4_HD_M_CTL 0x00c +# define VC4_HD_M_REGISTER_FILE_STANDBY (3 << 6) +# define VC4_HD_M_RAM_STANDBY (3 << 4) # define VC4_HD_M_SW_RST BIT(2) # define VC4_HD_M_ENABLE BIT(0)