clk: qcom: a53-pll: Add MSM8939 a53pll support

MSM8939 has 3 a53pll clocks with different frequency table for Cluster0,
Cluster1 and CCI.  It adds function qcom_a53pll_get_freq_tbl() to create
pll_freq_tbl from OPP, so that those a53pll frequencies can be defined
in DT with operating-points-v2 bindings rather than being coded in the
driver.  In this case, one compatible rather than three would be needed
for these 3 a53pll clocks.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20210704024032.11559-5-shawn.guo@linaro.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

diff --git a/drivers/clk/qcom/a53-pll.c b/drivers/clk/qcom/a53-pll.c
index 96a118b..9e6decb 100644 (file)
--- a/drivers/clk/qcom/a53-pll.c
+++ b/drivers/clk/qcom/a53-pll.c
@@ -6,9 +6,11 @@
  * Author: Georgi Djakov <georgi.djakov@linaro.org>
  */
 
+#include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
+#include <linux/pm_opp.h>
 #include <linux/regmap.h>
 #include <linux/module.h>
 
@@ -34,6 +36,55 @@ static const struct regmap_config a53pll_regmap_config = {
        .fast_io                = true,
 };
 
+static struct pll_freq_tbl *qcom_a53pll_get_freq_tbl(struct device *dev)
+{
+       struct pll_freq_tbl *freq_tbl;
+       unsigned long xo_freq;
+       unsigned long freq;
+       struct clk *xo_clk;
+       int count;
+       int ret;
+       int i;
+
+       xo_clk = devm_clk_get(dev, "xo");
+       if (IS_ERR(xo_clk))
+               return NULL;
+
+       xo_freq = clk_get_rate(xo_clk);
+
+       ret = devm_pm_opp_of_add_table(dev);
+       if (ret)
+               return NULL;
+
+       count = dev_pm_opp_get_opp_count(dev);
+       if (count <= 0)
+               return NULL;
+
+       freq_tbl = devm_kcalloc(dev, count + 1, sizeof(*freq_tbl), GFP_KERNEL);
+       if (!freq_tbl)
+               return NULL;
+
+       for (i = 0, freq = 0; i < count; i++, freq++) {
+               struct dev_pm_opp *opp;
+
+               opp = dev_pm_opp_find_freq_ceil(dev, &freq);
+               if (IS_ERR(opp))
+                       return NULL;
+
+               /* Skip the freq that is not divisible */
+               if (freq % xo_freq)
+                       continue;
+
+               freq_tbl[i].freq = freq;
+               freq_tbl[i].l = freq / xo_freq;
+               freq_tbl[i].n = 1;
+
+               dev_pm_opp_put(opp);
+       }
+
+       return freq_tbl;
+}
+
 static int qcom_a53pll_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
@@ -65,7 +116,12 @@ static int qcom_a53pll_probe(struct platform_device *pdev)
        pll->mode_reg = 0x00;
        pll->status_reg = 0x1c;
        pll->status_bit = 16;
-       pll->freq_tbl = a53pll_freq;
+
+       pll->freq_tbl = qcom_a53pll_get_freq_tbl(dev);
+       if (!pll->freq_tbl) {
+               /* Fall on a53pll_freq if no freq_tbl is found from OPP */
+               pll->freq_tbl = a53pll_freq;
+       }
 
        /* Use an unique name by appending @unit-address */
        init.name = devm_kasprintf(dev, GFP_KERNEL, "a53pll%s",
@@ -96,6 +152,7 @@ static int qcom_a53pll_probe(struct platform_device *pdev)
 
 static const struct of_device_id qcom_a53pll_match_table[] = {
        { .compatible = "qcom,msm8916-a53pll" },
+       { .compatible = "qcom,msm8939-a53pll" },
        { }
 };
 MODULE_DEVICE_TABLE(of, qcom_a53pll_match_table);