Alpha PLLs which do not support dynamic update feature need to be explicitly disabled before a rate change. The ones which do support dynamic update do so within a single vco range, so add a min/max freq check for such PLLs so they fall in the vco range.
Signed-off-by: Taniya Das <[email protected]> Signed-off-by: Rajendra Nayak <[email protected]> --- drivers/clk/qcom/clk-alpha-pll.c | 49 +++++++++++++++++++++++++++++++++------- drivers/clk/qcom/clk-alpha-pll.h | 3 +++ 2 files changed, 44 insertions(+), 8 deletions(-) diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c index 89c7fdb..6f90a86 100644 --- a/drivers/clk/qcom/clk-alpha-pll.c +++ b/drivers/clk/qcom/clk-alpha-pll.c @@ -382,16 +382,41 @@ 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) { + bool enabled; struct clk_alpha_pll *pll = to_clk_alpha_pll(hw); const struct pll_vco *vco; u32 l, off = pll->offset; u64 a; rate = alpha_pll_round_rate(rate, prate, &l, &a); - vco = alpha_pll_find_vco(pll, rate); - if (!vco) { - pr_err("alpha pll not in a valid vco range\n"); - return -EINVAL; + enabled = clk_hw_is_enabled(hw); + + if (pll->flags & SUPPORTS_DYNAMIC_UPDATE) { + /* + * PLLs which support dynamic updates support one single + * vco range, between min_rate and max_rate supported + */ + if (rate < pll->min_rate || rate > pll->max_rate) { + pr_err("alpha pll rate outside supported min/max range\n"); + return -EINVAL; + } + } else { + /* + * All alpha PLLs which do not support dynamic update, + * should be disabled before a vco update. + */ + if (enabled) + hw->init->ops->disable(hw); + + vco = alpha_pll_find_vco(pll, rate); + if (!vco) { + pr_err("alpha pll not in a valid vco range\n"); + return -EINVAL; + } + + regmap_update_bits(pll->clkr.regmap, off + PLL_USER_CTL, + PLL_VCO_MASK << PLL_VCO_SHIFT, + vco->val << PLL_VCO_SHIFT); } regmap_write(pll->clkr.regmap, off + PLL_L_VAL, l); @@ -404,13 +429,12 @@ static int clk_alpha_pll_set_rate(struct clk_hw *hw, unsigned long rate, regmap_write(pll->clkr.regmap, off + PLL_ALPHA_VAL_U, a >> 32); } - regmap_update_bits(pll->clkr.regmap, off + PLL_USER_CTL, - PLL_VCO_MASK << PLL_VCO_SHIFT, - vco->val << PLL_VCO_SHIFT); - 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); + return 0; } @@ -423,6 +447,15 @@ static long clk_alpha_pll_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long min_freq, max_freq; rate = alpha_pll_round_rate(rate, *prate, &l, &a); + + if (pll->flags & SUPPORTS_DYNAMIC_UPDATE) { + if (rate < pll->min_rate) + rate = pll->min_rate; + else if (rate > pll->max_rate) + rate = pll->max_rate; + return rate; + } + if (alpha_pll_find_vco(pll, rate)) return rate; diff --git a/drivers/clk/qcom/clk-alpha-pll.h b/drivers/clk/qcom/clk-alpha-pll.h index d6e1ee2..e43a9c0 100644 --- a/drivers/clk/qcom/clk-alpha-pll.h +++ b/drivers/clk/qcom/clk-alpha-pll.h @@ -37,8 +37,11 @@ struct clk_alpha_pll { #define SUPPORTS_OFFLINE_REQ BIT(0) #define SUPPORTS_16BIT_ALPHA BIT(1) #define SUPPORTS_FSM_MODE BIT(2) +#define SUPPORTS_DYNAMIC_UPDATE BIT(3) u8 flags; + unsigned long min_rate; + unsigned long max_rate; struct clk_regmap clkr; }; -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
