Re: [PATCH v1 1/3] clk: qcom: clk-alpha-pll: Add support for controlling Agera PLLs
From: Stephen Boyd <sboyd@kernel.org>
Date: 2020-09-15 00:14:11
Also in:
linux-arm-msm, linux-clk, lkml
Quoting Taniya Das (2020-09-08 10:07:26)
quoted hunk
diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c index 26139ef..fb27fcf 100644 --- a/drivers/clk/qcom/clk-alpha-pll.c +++ b/drivers/clk/qcom/clk-alpha-pll.c@@ -1561,3 +1571,75 @@ const struct clk_ops clk_alpha_pll_postdiv_lucid_ops = { .set_rate = clk_alpha_pll_postdiv_fabia_set_rate, }; EXPORT_SYMBOL_GPL(clk_alpha_pll_postdiv_lucid_ops); + +void clk_agera_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->user_ctl_val) + regmap_write(regmap, PLL_USER_CTL(pll), config->user_ctl_val); + + 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->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); +} +EXPORT_SYMBOL_GPL(clk_agera_pll_configure); + +static int alpha_pll_agera_set_rate(struct clk_hw *hw, unsigned long rate,
Why not clk_alpha_pll prefix? We should prefix the other PLL functions in here with clk_alpha_ like trion and fabia
+ unsigned long prate)
+{
+ struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
+ u32 l, alpha_width = pll_alpha_width(pll);
+ unsigned long rrate;
+ u64 a;
+
+ rrate = alpha_pll_round_rate(rate, prate, &l, &a, alpha_width);
+
+ /*
+ * Due to limited number of bits for fractional rate programming, the
+ * rounded up rate could be marginally higher than the requested rate.
+ */
+ if (rrate > (rate + PLL_RATE_MARGIN) || rrate < rate) {
+ pr_err("Call set rate on the PLL with rounded rates!\n");
+ return -EINVAL;
+ }
See commit f78f29079327 ("clk: qcom: alpha-pll: Make error prints more
informative") where I tried to make this better. Can you extract this
check into a function that helps us understand the error better?
+ + /* change L_VAL without having to go through the power on sequence */ + regmap_write(pll->clkr.regmap, PLL_L_VAL(pll), l); + regmap_write(pll->clkr.regmap, PLL_ALPHA_VAL(pll), a); + + /* Ensure that the write above goes through before proceeding. */ + mb();
regmap has an mb() in it. Remove this?
+
+ if (clk_hw_is_enabled(hw))
+ return wait_for_pll_enable_lock(pll);
+
+ return 0;
+}
+
+const struct clk_ops clk_alpha_pll_agera_ops = {
+ .enable = clk_alpha_pll_enable,
+ .disable = clk_alpha_pll_disable,
+ .is_enabled = clk_alpha_pll_is_enabled,
+ .recalc_rate = alpha_pll_fabia_recalc_rate,
+ .round_rate = clk_alpha_pll_round_rate,
+ .set_rate = alpha_pll_agera_set_rate,
+};
+EXPORT_SYMBOL_GPL(clk_alpha_pll_agera_ops);