Re: [PATCH 1/3] clk: qcom: clk-alpha-pll: add support for zonda pll

[Robert Foss]

Hey Jonathan,

On Thu, 13 May 2021 at 19:53, Jonathan Marek <jonathan@xxxxxxxx> wrote:
>
> Ported over from the downstream driver. Will be used by SM8250 CAMCC.
>
> Signed-off-by: Jonathan Marek <jonathan@xxxxxxxx>
> ---
>  drivers/clk/qcom/clk-alpha-pll.c | 245 +++++++++++++++++++++++++++++++
>  drivers/clk/qcom/clk-alpha-pll.h |   6 +
>  2 files changed, 251 insertions(+)
>
> diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
> index c6eb99169ddc..7b332a8935f4 100644
> --- a/drivers/clk/qcom/clk-alpha-pll.c
> +++ b/drivers/clk/qcom/clk-alpha-pll.c
> @@ -126,6 +126,19 @@ const u8 clk_alpha_pll_regs[][PLL_OFF_MAX_REGS] = {
>                 [PLL_OFF_TEST_CTL_U] = 0x1c,
>                 [PLL_OFF_STATUS] = 0x2c,
>         },
> +       [CLK_ALPHA_PLL_TYPE_ZONDA] =  {
> +               [PLL_OFF_L_VAL] = 0x04,
> +               [PLL_OFF_ALPHA_VAL] = 0x08,
> +               [PLL_OFF_USER_CTL] = 0x0c,
> +               [PLL_OFF_CONFIG_CTL] = 0x10,
> +               [PLL_OFF_CONFIG_CTL_U] = 0x14,
> +               [PLL_OFF_CONFIG_CTL_U1] = 0x18,
> +               [PLL_OFF_TEST_CTL] = 0x1c,
> +               [PLL_OFF_TEST_CTL_U] = 0x20,
> +               [PLL_OFF_TEST_CTL_U1] = 0x24,
> +               [PLL_OFF_OPMODE] = 0x28,
> +               [PLL_OFF_STATUS] = 0x38,
> +       },
>  };
>  EXPORT_SYMBOL_GPL(clk_alpha_pll_regs);
>
> @@ -162,6 +175,11 @@ EXPORT_SYMBOL_GPL(clk_alpha_pll_regs);
>  #define LUCID_5LPE_PLL_LATCH_INPUT     BIT(14)
>  #define LUCID_5LPE_ENABLE_VOTE_RUN     BIT(21)
>
> +/* ZONDA PLL specific */
> +#define ZONDA_PLL_OUT_MASK     0xf
> +#define ZONDA_STAY_IN_CFA      BIT(16)
> +#define ZONDA_PLL_FREQ_LOCK_DET        BIT(29)
> +
>  #define pll_alpha_width(p)                                     \
>                 ((PLL_ALPHA_VAL_U(p) - PLL_ALPHA_VAL(p) == 4) ? \
>                                  ALPHA_REG_BITWIDTH : ALPHA_REG_16BIT_WIDTH)
> @@ -208,6 +226,9 @@ static int wait_for_pll(struct clk_alpha_pll *pll, u32 mask, bool inverse,
>  #define wait_for_pll_enable_lock(pll) \
>         wait_for_pll(pll, PLL_LOCK_DET, 0, "enable")
>
> +#define wait_for_zonda_pll_freq_lock(pll) \
> +       wait_for_pll(pll, ZONDA_PLL_FREQ_LOCK_DET, 0, "freq enable")
> +
>  #define wait_for_pll_disable(pll) \
>         wait_for_pll(pll, PLL_ACTIVE_FLAG, 1, "disable")
>
> @@ -1398,6 +1419,13 @@ const struct clk_ops clk_alpha_pll_postdiv_fabia_ops = {
>  };
>  EXPORT_SYMBOL_GPL(clk_alpha_pll_postdiv_fabia_ops);
>
> +const struct clk_ops clk_alpha_pll_postdiv_zonda_ops = {
> +       .recalc_rate = clk_alpha_pll_postdiv_fabia_recalc_rate,
> +       .round_rate = clk_alpha_pll_postdiv_fabia_round_rate,
> +       .set_rate = clk_alpha_pll_postdiv_fabia_set_rate,
> +};
> +EXPORT_SYMBOL(clk_alpha_pll_postdiv_zonda_ops);
> +
>  /**
>   * clk_lucid_pll_configure - configure the lucid pll
>   *
> @@ -1777,3 +1805,220 @@ const struct clk_ops clk_alpha_pll_postdiv_lucid_5lpe_ops = {
>         .set_rate = clk_lucid_5lpe_pll_postdiv_set_rate,
>  };
>  EXPORT_SYMBOL(clk_alpha_pll_postdiv_lucid_5lpe_ops);
> +
> +void clk_zonda_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
> +                               const struct alpha_pll_config *config)
> +{
> +       if (config->l)
> +               regmap_write(regmap, PLL_L_VAL(pll), config->l);
> +
> +       if (config->alpha)
> +               regmap_write(regmap, PLL_ALPHA_VAL(pll), config->alpha);
> +
> +       if (config->config_ctl_val)
> +               regmap_write(regmap, PLL_CONFIG_CTL(pll),
> +                               config->config_ctl_val);
> +
> +       if (config->config_ctl_hi_val)
> +               regmap_write(regmap, PLL_CONFIG_CTL_U(pll),
> +                               config->config_ctl_hi_val);
> +
> +       if (config->config_ctl_hi1_val)
> +               regmap_write(regmap, PLL_CONFIG_CTL_U1(pll),
> +                               config->config_ctl_hi1_val);
> +
> +       if (config->user_ctl_val)
> +               regmap_write(regmap, PLL_USER_CTL(pll),
> +                               config->user_ctl_val);
> +
> +       if (config->user_ctl_hi_val)
> +               regmap_write(regmap, PLL_USER_CTL_U(pll),
> +                               config->user_ctl_hi_val);
> +
> +       if (config->user_ctl_hi1_val)
> +               regmap_write(regmap, PLL_USER_CTL_U1(pll),
> +                               config->user_ctl_hi1_val);
> +
> +       if (config->test_ctl_val)
> +               regmap_write(regmap, PLL_TEST_CTL(pll),
> +                               config->test_ctl_val);
> +
> +       if (config->test_ctl_hi_val)
> +               regmap_write(regmap, PLL_TEST_CTL_U(pll),
> +                               config->test_ctl_hi_val);
> +
> +       if (config->test_ctl_hi1_val)
> +               regmap_write(regmap, PLL_TEST_CTL_U1(pll),
> +                               config->test_ctl_hi1_val);
> +
> +       regmap_update_bits(regmap, PLL_MODE(pll),
> +                        PLL_BYPASSNL, 0);
> +
> +       /* Disable PLL output */
> +       regmap_update_bits(regmap, PLL_MODE(pll), PLL_OUTCTRL, 0);
> +
> +       /* Set operation mode to OFF */
> +       regmap_write(regmap, PLL_OPMODE(pll), PLL_STANDBY);
> +
> +       /* PLL should be in OFF mode before continuing */
> +       wmb();
> +
> +       /* Place the PLL in STANDBY mode */
> +       regmap_update_bits(regmap, PLL_MODE(pll), PLL_RESET_N, PLL_RESET_N);
> +}
> +
> +static int clk_zonda_pll_enable(struct clk_hw *hw)
> +{
> +       struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
> +       struct regmap *regmap = pll->clkr.regmap;
> +       u32 val;
> +       int ret;
> +
> +       ret = regmap_read(regmap, PLL_MODE(pll), &val);
> +       if (ret)
> +               return ret;
> +
> +       /* If in FSM mode, just vote for it */
> +       if (val & PLL_VOTE_FSM_ENA) {
> +               ret = clk_enable_regmap(hw);
> +               if (ret)
> +                       return ret;
> +               return wait_for_pll_enable_active(pll);
> +       }
> +
> +       /* Get the PLL out of bypass mode */
> +       regmap_update_bits(regmap, PLL_MODE(pll), PLL_BYPASSNL, PLL_BYPASSNL);
> +
> +       /*
> +        * H/W requires a 1us delay between disabling the bypass and
> +        * de-asserting the reset.
> +        */
> +       mb();
> +       udelay(1);
> +
> +       regmap_update_bits(regmap, PLL_MODE(pll), PLL_RESET_N, PLL_RESET_N);
> +
> +       /* Set operation mode to RUN */
> +       regmap_write(regmap, PLL_OPMODE(pll), PLL_RUN);
> +
> +       ret = regmap_read(regmap, PLL_TEST_CTL(pll), &val);
> +       if (ret)
> +               return ret;
> +
> +       /* If cfa mode then poll for freq lock */
> +       if (val & ZONDA_STAY_IN_CFA)
> +               ret = wait_for_zonda_pll_freq_lock(pll);
> +       else
> +               ret = wait_for_pll_enable_lock(pll);
> +       if (ret)
> +               return ret;
> +
> +       /* Enable the PLL outputs */
> +       ret = regmap_update_bits(regmap, PLL_USER_CTL(pll),
> +                                ZONDA_PLL_OUT_MASK, ZONDA_PLL_OUT_MASK);
> +       if (ret)
> +               return ret;
> +
> +       /* Enable the global PLL outputs */
> +       ret = regmap_update_bits(regmap, PLL_MODE(pll),
> +                                PLL_OUTCTRL, PLL_OUTCTRL);
> +       if (ret)
> +               return ret;
> +
> +       /* Ensure that the write above goes through before returning. */
> +       mb();
> +
> +       return 0;
> +}
> +
> +static void clk_zonda_pll_disable(struct clk_hw *hw)
> +{
> +       struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
> +       struct regmap *regmap = pll->clkr.regmap;
> +       u32 val;
> +       int ret;
> +
> +       ret = regmap_read(regmap, PLL_MODE(pll), &val);
> +       if (ret)
> +               return;
> +
> +       /* If in FSM mode, just unvote it */
> +       if (val & PLL_VOTE_FSM_ENA) {
> +               clk_disable_regmap(hw);
> +               return;
> +       }
> +
> +       /* Disable the global PLL output */
> +       ret = regmap_update_bits(regmap, PLL_MODE(pll), PLL_OUTCTRL, 0);
> +
> +       /* Disable the PLL outputs */
> +       regmap_update_bits(regmap, PLL_USER_CTL(pll), ZONDA_PLL_OUT_MASK, 0);
> +
> +       /* Put the PLL in bypass and reset */
> +       regmap_update_bits(regmap, PLL_MODE(pll), PLL_RESET_N | PLL_BYPASSNL, 0);
> +
> +       /* Place the PLL mode in OFF state */
> +       regmap_write(regmap, PLL_OPMODE(pll), 0x0);
> +}
> +
> +static int clk_zonda_pll_set_rate(struct clk_hw *hw, unsigned long rate,
> +                                 unsigned long prate)
> +{
> +       struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
> +       unsigned long rrate;
> +       u32 test_ctl_val;
> +       u32 l;
> +       u64 a;
> +       int ret;
> +
> +       rrate = alpha_pll_round_rate(rate, prate, &l, &a, ALPHA_BITWIDTH);
> +
> +       ret = alpha_pll_check_rate_margin(hw, rrate, rate);
> +       if (ret < 0)
> +               return ret;
> +
> +       regmap_write(pll->clkr.regmap, PLL_ALPHA_VAL(pll), a);
> +       regmap_write(pll->clkr.regmap, PLL_L_VAL(pll), l);
> +
> +       /* Wait before polling for the frequency latch */
> +       udelay(5);
> +
> +       /* Read stay in cfa mode */
> +       ret = regmap_read(pll->clkr.regmap, PLL_TEST_CTL(pll), &test_ctl_val);
> +       if (ret)
> +               return ret;
> +
> +       /* If cfa mode then poll for freq lock */
> +       if (test_ctl_val & ZONDA_STAY_IN_CFA)
> +               ret = wait_for_zonda_pll_freq_lock(pll);
> +       else
> +               ret = wait_for_pll_enable_lock(pll);
> +       if (ret)
> +               return ret;
> +
> +       /* Wait for PLL output to stabilize */
> +       udelay(100);
> +       return 0;
> +}
> +
> +static unsigned long
> +clk_zonda_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
> +{
> +       struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
> +       u32 l, frac;
> +
> +       regmap_read(pll->clkr.regmap, PLL_L_VAL(pll), &l);
> +       regmap_read(pll->clkr.regmap, PLL_ALPHA_VAL(pll), &frac);
> +
> +       return alpha_pll_calc_rate(parent_rate, l, frac, ALPHA_BITWIDTH);
> +}
> +
> +const struct clk_ops clk_alpha_pll_zonda_ops = {
> +       .enable = clk_zonda_pll_enable,
> +       .disable = clk_zonda_pll_disable,
> +       .is_enabled = clk_trion_pll_is_enabled,
> +       .recalc_rate = clk_zonda_pll_recalc_rate,
> +       .round_rate = clk_alpha_pll_round_rate,
> +       .set_rate = clk_zonda_pll_set_rate,
> +};
> +EXPORT_SYMBOL(clk_alpha_pll_zonda_ops);
> diff --git a/drivers/clk/qcom/clk-alpha-pll.h b/drivers/clk/qcom/clk-alpha-pll.h
> index 6943e933be0f..4871af27cf76 100644
> --- a/drivers/clk/qcom/clk-alpha-pll.h
> +++ b/drivers/clk/qcom/clk-alpha-pll.h
> @@ -16,6 +16,7 @@ enum {
>         CLK_ALPHA_PLL_TYPE_TRION,
>         CLK_ALPHA_PLL_TYPE_LUCID = CLK_ALPHA_PLL_TYPE_TRION,
>         CLK_ALPHA_PLL_TYPE_AGERA,
> +       CLK_ALPHA_PLL_TYPE_ZONDA,
>         CLK_ALPHA_PLL_TYPE_MAX,
>  };
>
> @@ -148,6 +149,9 @@ extern const struct clk_ops clk_alpha_pll_lucid_5lpe_ops;
>  extern const struct clk_ops clk_alpha_pll_fixed_lucid_5lpe_ops;
>  extern const struct clk_ops clk_alpha_pll_postdiv_lucid_5lpe_ops;
>
> +extern const struct clk_ops clk_alpha_pll_zonda_ops;
> +extern const struct clk_ops clk_alpha_pll_postdiv_zonda_ops;
> +
>  void clk_alpha_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
>                              const struct alpha_pll_config *config);
>  void clk_fabia_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
> @@ -159,6 +163,8 @@ void clk_agera_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
>  #define clk_lucid_pll_configure(pll, regmap, config) \
>         clk_trion_pll_configure(pll, regmap, config)
>
> +void clk_zonda_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
> +                            const struct alpha_pll_config *config);
>
>
>  #endif

I'm seeing some checkpatch --strict warnings, with those fixed this
patch looks good to me.

Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>