Re: Re: [PATCH] drm/sun4i: dw-hdmi: Fix HDMI PHY clock setup

From: Jernej Škrabec
Date: Tue Sep 14 2021 - 11:42:50 EST


Hi!

Dne torek, 14. september 2021 ob 10:59:22 CEST je Ondřej Jirman napisal(a):
> Hello Jernej,
>
> On Mon, Sep 13, 2021 at 07:21:54PM +0200, Jernej Skrabec wrote:
> > Recent rework, which made HDMI PHY driver a platform device, inadvertely
> > reversed clock setup order. HW is very touchy about it. Proper way is to
> > handle controllers resets and clocks first and HDMI PHYs second.
> >
> > Currently, without this fix, first mode set completely fails (nothing on
> > HDMI monitor) on H3 era PHYs. On H6, it still somehow work.
> >
> > Move HDMI PHY reset & clocks handling to sun8i_hdmi_phy_init() which
> > will assure that code is executed after controllers reset & clocks are
> > handled. Additionally, add sun8i_hdmi_phy_deinit() which will deinit
> > them at controllers driver unload.
> >
> > Tested on A64, H3, H6 and R40.
> >
> > Fixes: 9bf3797796f5 ("drm/sun4i: dw-hdmi: Make HDMI PHY into a platform
device")
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c | 7 +-
> > drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h | 4 +-
> > drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c | 97 ++++++++++++++------------
> > 3 files changed, 61 insertions(+), 47 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c b/drivers/gpu/drm/sun4i/
sun8i_dw_hdmi.c
> > index f75fb157f2ff..5fa5407ac583 100644
> > --- a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c
> > +++ b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c
> > @@ -216,11 +216,13 @@ static int sun8i_dw_hdmi_bind(struct device *dev,
struct device *master,
> > goto err_disable_clk_tmds;
> > }
>
> ^^^ This looks like...
>
> > + ret = sun8i_hdmi_phy_init(hdmi->phy);
> > + if (ret)
> > + return ret;
>
> ... you need 'goto err_disable_clk_tmds;' here, instead.

Ah, right. Will fix in v2.

>
> > +
> > drm_encoder_helper_add(encoder,
&sun8i_dw_hdmi_encoder_helper_funcs);
> > drm_simple_encoder_init(drm, encoder, DRM_MODE_ENCODER_TMDS);
> >
> > - sun8i_hdmi_phy_init(hdmi->phy);
> > -
> > plat_data->mode_valid = hdmi->quirks->mode_valid;
> > plat_data->use_drm_infoframe = hdmi->quirks->use_drm_infoframe;
> > sun8i_hdmi_phy_set_ops(hdmi->phy, plat_data);
> > @@ -262,6 +264,7 @@ static void sun8i_dw_hdmi_unbind(struct device *dev,
struct device *master,
> > struct sun8i_dw_hdmi *hdmi = dev_get_drvdata(dev);
> >
> > dw_hdmi_unbind(hdmi->hdmi);
> > + sun8i_hdmi_phy_deinit(hdmi->phy);
> > clk_disable_unprepare(hdmi->clk_tmds);
> > reset_control_assert(hdmi->rst_ctrl);
> > gpiod_set_value(hdmi->ddc_en, 0);
> > diff --git a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h b/drivers/gpu/drm/sun4i/
sun8i_dw_hdmi.h
> > index 74f6ed0e2570..bffe1b9cd3dc 100644
> > --- a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
> > +++ b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
> > @@ -169,6 +169,7 @@ struct sun8i_hdmi_phy {
> > struct clk *clk_phy;
> > struct clk *clk_pll0;
> > struct clk *clk_pll1;
> > + struct device *dev;
> > unsigned int rcal;
> > struct regmap *regs;
> > struct reset_control *rst_phy;
> > @@ -205,7 +206,8 @@ encoder_to_sun8i_dw_hdmi(struct drm_encoder *encoder)
> >
> > int sun8i_hdmi_phy_get(struct sun8i_dw_hdmi *hdmi, struct device_node
*node);
> >
> > -void sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy);
> > +int sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy);
> > +void sun8i_hdmi_phy_deinit(struct sun8i_hdmi_phy *phy);
> > void sun8i_hdmi_phy_set_ops(struct sun8i_hdmi_phy *phy,
> > struct dw_hdmi_plat_data *plat_data);
> >
> > diff --git a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c b/drivers/gpu/drm/
sun4i/sun8i_hdmi_phy.c
> > index c9239708d398..78b152973957 100644
> > --- a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
> > +++ b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
> > @@ -506,9 +506,60 @@ static void sun8i_hdmi_phy_init_h3(struct
sun8i_hdmi_phy *phy)
> > phy->rcal = (val & SUN8I_HDMI_PHY_ANA_STS_RCAL_MASK) >> 2;
> > }
> >
> > -void sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy)
> > +int sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy)
> > {
> > + int ret;
> > +
> > + ret = reset_control_deassert(phy->rst_phy);
> > + if (ret) {
> > + dev_err(phy->dev, "Cannot deassert phy reset control:
%d\n", ret);
> > + return ret;
> > + }
> > +
> > + ret = clk_prepare_enable(phy->clk_bus);
> > + if (ret) {
> > + dev_err(phy->dev, "Cannot enable bus clock: %d\n",
ret);
> > + goto err_deassert_rst_phy;
>
> I know it was there before, but please:
>
> s/deassert/assert/

Ok.

Best regards,
Jernej

>
> kind regards,
> o.
>
> > + }
> > +
> > + ret = clk_prepare_enable(phy->clk_mod);
> > + if (ret) {
> > + dev_err(phy->dev, "Cannot enable mod clock: %d\n",
ret);
> > + goto err_disable_clk_bus;
> > + }
> > +
> > + if (phy->variant->has_phy_clk) {
> > + ret = sun8i_phy_clk_create(phy, phy->dev,
> > + phy->variant-
>has_second_pll);
> > + if (ret) {
> > + dev_err(phy->dev, "Couldn't create the PHY
clock\n");
> > + goto err_disable_clk_mod;
> > + }
> > +
> > + clk_prepare_enable(phy->clk_phy);
> > + }
> > +
> > phy->variant->phy_init(phy);
> > +
> > + return 0;
> > +
> > +err_disable_clk_mod:
> > + clk_disable_unprepare(phy->clk_mod);
> > +err_disable_clk_bus:
> > + clk_disable_unprepare(phy->clk_bus);
> > +err_deassert_rst_phy:
> > + reset_control_assert(phy->rst_phy);
> > +
> > + return ret;
> > +}
> > +
> >
> > [......]
>