Re: [PATCH v2 10/10] clk: qcom: Fix .set_rate to handle alpha PLLs w/wo dynamic update

Stephen Boyd
2016-08-24T06:26:16Z

On 08/11, Rajendra Nayak wrote:
> diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
> index 2184dc1..68c90f3 100644
> --- a/drivers/clk/qcom/clk-alpha-pll.c
> +++ b/drivers/clk/qcom/clk-alpha-pll.c
> @@ -113,6 +113,11 @@ static int wait_for_pll_offline(struct clk_alpha_pll *pll, u32 mask)
> #define PLL_OFFLINE_ACK BIT(28)
> #define PLL_ACTIVE_FLAG BIT(30)
>
> +/* alpha pll with dynamic update support */
> +#define PLL_UPDATE BIT(22)
> +#define PLL_HW_LOGIC_BYPASS BIT(23)
> +#define PLL_ACK_LATCH BIT(29)

These need to move next to associated registers.

> +
> void clk_alpha_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
> const struct alpha_pll_config *config)
> {
> @@ -366,6 +402,7 @@ clk_alpha_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
> static int clk_alpha_pll_set_rate(struct clk_hw *hw, unsigned long rate,
> unsigned long prate)
> {
> + int enabled;

bool

> struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
> const struct pll_vco *vco;
> u32 l, off = pll->offset;
> @@ -378,6 +415,11 @@ static int clk_alpha_pll_set_rate(struct clk_hw *hw, unsigned long rate,
> return -EINVAL;
> }
>
> + enabled = hw->init->ops->is_enabled(hw);

We have clk_hw_is_enabled() for this.

> +
> + if (!(pll->flags & SUPPORTS_DYNAMIC_UPDATE) && enabled)
> + hw->init->ops->disable(hw);

Please call the function directly instead of going through the
init structure to get the clk ops.

> +
> a <<= (ALPHA_REG_BITWIDTH - ALPHA_BITWIDTH);
>
> regmap_write(pll->clkr.regmap, off + PLL_L_VAL, l);
> @@ -391,6 +433,12 @@ static int clk_alpha_pll_set_rate(struct clk_hw *hw, unsigned long rate,
> regmap_update_bits(pll->clkr.regmap, off + PLL_USER_CTL, PLL_ALPHA_EN,
> PLL_ALPHA_EN);
>
> + if (!(pll->flags & SUPPORTS_DYNAMIC_UPDATE) && enabled)
> + hw->init->ops->enable(hw);
> +
> + if (pll->flags & SUPPORTS_DYNAMIC_UPDATE)
> + clk_alpha_pll_dynamic_update(pll);
> +

Perhaps write it as

if (pll->flags & SUPPORTS_DYNAMIC_UPDATE)
clk_alpha_pll_dynamic_update()
else if (enabled)
toggle the enable bit...

--
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