Re: [PATCH v2 12/26] drm/sun4i: Add support for multiple DW HDMI PHY clock parents
From: Jernej Åkrabec
Date: Fri May 18 2018 - 10:20:15 EST
Hi,
Dne petek, 18. maj 2018 ob 17:09:40 CEST je Sergey Suloev napisal(a):
> Hi, guys,
>
> On 05/18/2018 05:46 PM, Jernej Åkrabec wrote:
> > Hi,
> >
> > Dne petek, 18. maj 2018 ob 12:01:16 CEST je Maxime Ripard napisal(a):
> >> On Fri, May 18, 2018 at 03:15:22PM +0530, Jagan Teki wrote:
> >>> From: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> >>>
> >>> Some SoCs with DW HDMI have multiple possible clock parents, like A64
> >>> and R40.
> >>>
> >>> Expand HDMI PHY clock driver to support second clock parent.
> >>>
> >>> Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> >>> Signed-off-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
> >>> ---
> >>> Changes for v2:
> >>> - new patch
> >>>
> >>> drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h | 9 ++-
> >>> drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c | 33 ++++++++---
> >>> drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c | 89
> >>> ++++++++++++++++++++++-------- 3 files changed, 96 insertions(+), 35
> >>> deletions(-)
> >>>
> >>> diff --git a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
> >>> b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h index 79154f0f674a..303189d6602c
> >>> 100644
> >>> --- a/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
> >>> +++ b/drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h
> >>> @@ -98,7 +98,8 @@
> >>>
> >>> #define SUN8I_HDMI_PHY_PLL_CFG1_LDO2_EN BIT(29)
> >>> #define SUN8I_HDMI_PHY_PLL_CFG1_LDO1_EN BIT(28)
> >>> #define SUN8I_HDMI_PHY_PLL_CFG1_HV_IS_33 BIT(27)
> >>>
> >>> -#define SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL BIT(26)
> >>> +#define SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK BIT(26)
> >>> +#define SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_SHIFT 26
> >>>
> >>> #define SUN8I_HDMI_PHY_PLL_CFG1_PLLEN BIT(25)
> >>> #define SUN8I_HDMI_PHY_PLL_CFG1_LDO_VSET(x) ((x) << 22)
> >>> #define SUN8I_HDMI_PHY_PLL_CFG1_UNKNOWN(x) ((x) << 20)
> >>>
> >>> @@ -146,7 +147,7 @@
> >>>
> >>> struct sun8i_hdmi_phy;
> >>>
> >>> struct sun8i_hdmi_phy_variant {
> >>>
> >>> - bool has_phy_clk;
> >>> + int phy_clk_num;
> >>>
> >>> void (*phy_init)(struct sun8i_hdmi_phy *phy);
> >>> void (*phy_disable)(struct dw_hdmi *hdmi,
> >>>
> >>> struct sun8i_hdmi_phy *phy);
> >>>
> >>> @@ -160,6 +161,7 @@ struct sun8i_hdmi_phy {
> >>>
> >>> struct clk *clk_mod;
> >>> struct clk *clk_phy;
> >>> struct clk *clk_pll0;
> >>>
> >>> + struct clk *clk_pll1;
> >>>
> >>> unsigned int rcal;
> >>> struct regmap *regs;
> >>> struct reset_control *rst_phy;
> >>>
> >>> @@ -188,6 +190,7 @@ void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi
> >>> *hdmi);
> >>>
> >>> void sun8i_hdmi_phy_init(struct sun8i_hdmi_phy *phy);
> >>> const struct dw_hdmi_phy_ops *sun8i_hdmi_phy_get_ops(void);
> >>>
> >>> -int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device
> >>> *dev);
> >>> +int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device
> >>> *dev,
> >>> + int clk_num);
> >>>
> >>> #endif /* _SUN8I_DW_HDMI_H_ */
> >>>
> >>> diff --git a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
> >>> b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c index
> >>> 5a52fc489a9d..0eadf087fc46
> >>> 100644
> >>> --- a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
> >>> +++ b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
> >>> @@ -183,7 +183,13 @@ static int sun8i_hdmi_phy_config_h3(struct dw_hdmi
> >>> *hdmi,>
> >>>
> >>> regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_ANA_CFG1_REG,
> >>>
> >>> SUN8I_HDMI_PHY_ANA_CFG1_TXEN_MASK, 0);
> >>>
> >>> - regmap_write(phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG, pll_cfg1_init);
> >>> + /*
> >>> + * NOTE: We have to be careful not to overwrite PHY parent
> >>> + * clock selection bit and clock divider.
> >>> + */
> >>> + regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG,
> >>> + (u32)~SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK,
> >>> + pll_cfg1_init);
> >>>
> >>> regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_PLL_CFG2_REG,
> >>>
> >>> (u32)~SUN8I_HDMI_PHY_PLL_CFG2_PREDIV_MSK,
> >>> pll_cfg2_init);
> >>>
> >>> @@ -232,7 +238,7 @@ static int sun8i_hdmi_phy_config(struct dw_hdmi
> >>> *hdmi,
> >>> void *data,>
> >>>
> >>> regmap_update_bits(phy->regs, SUN8I_HDMI_PHY_DBG_CTRL_REG,
> >>>
> >>> SUN8I_HDMI_PHY_DBG_CTRL_POL_MASK, val);
> >>>
> >>> - if (phy->variant->has_phy_clk)
> >>> + if (phy->variant->phy_clk_num)
> >>>
> >>> clk_set_rate(phy->clk_phy, mode->crtc_clock * 1000);
> >>>
> >>> return phy->variant->phy_config(hdmi, phy, mode->crtc_clock * 1000);
> >>>
> >>> @@ -393,7 +399,7 @@ static const struct sun8i_hdmi_phy_variant
> >>> sun8i_a83t_hdmi_phy = {>
> >>>
> >>> };
> >>>
> >>> static const struct sun8i_hdmi_phy_variant sun8i_h3_hdmi_phy = {
> >>>
> >>> - .has_phy_clk = true,
> >>> + .phy_clk_num = 1,
> >>>
> >>> .phy_init = &sun8i_hdmi_phy_init_h3,
> >>> .phy_disable = &sun8i_hdmi_phy_disable_h3,
> >>> .phy_config = &sun8i_hdmi_phy_config_h3,
> >>>
> >>> @@ -464,7 +470,7 @@ int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi,
> >>> struct device_node *node)>
> >>>
> >>> goto err_put_clk_bus;
> >>>
> >>> }
> >>>
> >>> - if (phy->variant->has_phy_clk) {
> >>> + if (phy->variant->phy_clk_num) {
> >>>
> >>> phy->clk_pll0 = of_clk_get_by_name(node, "pll-0");
> >>> if (IS_ERR(phy->clk_pll0)) {
> >>>
> >>> dev_err(dev, "Could not get pll-0 clock\n");
> >>>
> >>> @@ -472,7 +478,16 @@ int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi
> >>> *hdmi,
> >>> struct device_node *node)>
> >>>
> >>> goto err_put_clk_mod;
> >>>
> >>> }
> >>>
> >>> - ret = sun8i_phy_clk_create(phy, dev);
> >>> + if (phy->variant->phy_clk_num) {
> >>> + phy->clk_pll1 = of_clk_get_by_name(node, "pll-1");
> >>> + if (IS_ERR(phy->clk_pll1)) {
> >>> + dev_err(dev, "Could not get pll-1 clock\n");
> >>> + ret = PTR_ERR(phy->clk_pll1);
> >>> + goto err_put_clk_mod;
> >>> + }
> >>> + }
> >>> +
> >>
> >> You have a bug here. If phy_clk_num == 1, you'll still try to lookup
> >> pll-1.
> >
> > This is actually WIP patch taken from my github. This issue was fixed
> > already locally on disk. I thought Jagan will not use it until SRAM C
> > patches land.>
> >> And this is a bit sloppy, since if phy_clk_num == 3, you won't try to
> >> lookup pll-2 either.
> >
> > It is highly unlikely this will be higher than 2, at least for this HDMI
> > PHY, since it has only 1 bit reserved for parent selection. But since I
> > have to fix it, I'll add ">= 2"
> >
> >>> + ret = sun8i_phy_clk_create(phy, dev, phy->variant->phy_clk_num);
> >>>
> >>> if (ret) {
> >>>
> >>> dev_err(dev, "Couldn't create the PHY clock\n");
> >>> goto err_put_clk_pll0;
> >>>
> >>> @@ -515,8 +530,8 @@ int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi,
> >>> struct device_node *node)>
> >>>
> >>> err_put_rst_phy:
> >>> reset_control_put(phy->rst_phy);
> >>>
> >>> err_put_clk_pll0:
> >>> - if (phy->variant->has_phy_clk)
> >>> - clk_put(phy->clk_pll0);
> >>> + clk_put(phy->clk_pll0);
> >>> + clk_put(phy->clk_pll1);
> >>>
> >>> err_put_clk_mod:
> >>> clk_put(phy->clk_mod);
> >>>
> >>> err_put_clk_bus:
> >>> @@ -536,8 +551,8 @@ void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi
> >>> *hdmi)
> >>>
> >>> reset_control_put(phy->rst_phy);
> >>>
> >>> - if (phy->variant->has_phy_clk)
> >>> - clk_put(phy->clk_pll0);
> >>> + clk_put(phy->clk_pll0);
> >>> + clk_put(phy->clk_pll1);
> >>>
> >>> clk_put(phy->clk_mod);
> >>> clk_put(phy->clk_bus);
> >>>
> >>> }
> >>>
> >>> diff --git a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c
> >>> b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c index
> >>> faea449812f8..85b12fc96dbc 100644
> >>> --- a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c
> >>> +++ b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c
> >>> @@ -22,29 +22,36 @@ static int sun8i_phy_clk_determine_rate(struct
> >>> clk_hw
> >>> *hw,>
> >>>
> >>> {
> >>>
> >>> unsigned long rate = req->rate;
> >>> unsigned long best_rate = 0;
> >>>
> >>> - struct clk_hw *parent;
> >>> + struct clk_hw *best_parent = NULL;
> >>> + struct clk_hw *parent = NULL;
> >>>
> >>> int best_div = 1;
> >>>
> >>> - int i;
> >>> + int i, p;
> >>>
> >>> - parent = clk_hw_get_parent(hw);
> >>> -
> >>> - for (i = 1; i <= 16; i++) {
> >>> - unsigned long ideal = rate * i;
> >>> - unsigned long rounded;
> >>> -
> >>> - rounded = clk_hw_round_rate(parent, ideal);
> >>> -
> >>> - if (rounded == ideal) {
> >>> - best_rate = rounded;
> >>> - best_div = i;
> >>> - break;
> >>> - }
> >>> + for (p = 0; p < clk_hw_get_num_parents(hw); p++) {
> >>> + parent = clk_hw_get_parent_by_index(hw, p);
> >>> + if (!parent)
> >>> + continue;
> >>>
> >>> - if (!best_rate ||
> >>> - abs(rate - rounded / i) <
> >>> - abs(rate - best_rate / best_div)) {
> >>> - best_rate = rounded;
> >>> - best_div = i;
> >>> + for (i = 1; i <= 16; i++) {
> >>> + unsigned long ideal = rate * i;
> >>> + unsigned long rounded;
> >>> +
> >>> + rounded = clk_hw_round_rate(parent, ideal);
> >>> +
> >>> + if (rounded == ideal) {
> >>> + best_rate = rounded;
> >>> + best_div = i;
> >>> + best_parent = parent;
> >>> + break;
> >>> + }
> >>> +
> >>> + if (!best_rate ||
> >>> + abs(rate - rounded / i) <
> >>> + abs(rate - best_rate / best_div)) {
> >>> + best_rate = rounded;
> >>> + best_div = i;
> >>> + best_parent = parent;
> >>> + }
> >>>
> >>> }
> >>>
> >>> }
> >>>
> >>> @@ -95,22 +102,58 @@ static int sun8i_phy_clk_set_rate(struct clk_hw
> >>> *hw,
> >>> unsigned long rate,>
> >>>
> >>> return 0;
> >>>
> >>> }
> >>>
> >>> +static u8 sun8i_phy_clk_get_parent(struct clk_hw *hw)
> >>> +{
> >>> + struct sun8i_phy_clk *priv = hw_to_phy_clk(hw);
> >>> + u32 reg;
> >>> +
> >>> + regmap_read(priv->phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG, ®);
> >>> + reg = (reg & SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK) >>
> >>> + SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_SHIFT;
> >>> +
> >>> + return reg;
> >>> +}
> >>> +
> >>> +static int sun8i_phy_clk_set_parent(struct clk_hw *hw, u8 index)
> >>> +{
> >>> + struct sun8i_phy_clk *priv = hw_to_phy_clk(hw);
> >>> +
> >>> + if (index > 1)
> >>> + return -EINVAL;
> >>> +
> >>> + regmap_update_bits(priv->phy->regs, SUN8I_HDMI_PHY_PLL_CFG1_REG,
> >>> + SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_MSK,
> >>> + index << SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL_SHIFT);
> >>> +
> >>> + return 0;
> >>> +}
> >>> +
> >>
> >> The DT bindings changes and the clk changes should be part of separate
> >> patches.
> >
> > By DT bindings changes you mean code which reads DT and not DT
> > documentation, right?
> >
> > Ok, I'll split it.
> >
> > BTW, I'll resend fixed version of this patch for my R40 HDMI series, since
> > there is nothing to hold it back, unlike for this.
> >
> > Best regards,
> > Jernej
> >
> >
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
> you have been talking about SRAM patches, required for A64 DE2, for
> about a half a year.
> May I ask you to explain in a couple of words why they are so important ?
> I am really curious because I have DE2 already working on my A64 without
> those magic patches..
>
You probably have HDMI enabled in U-Boot, right? If you disable that driver in
U-Boot, Linux driver shouldn't work anymore. There is consensus that Linux A64
DE2 driver shouldn't rely on U-Boot setting bits. Those SRAM C patches will
probably also affect how DT DE2 entries are written, especially if it will be
implemented as a bus, as once proposed by Icenowy.
Best regards,
Jernej