-----Original Message-----
From: Stephen Boyd <sboyd@kernel.org>
Sent: Monday, March 19, 2018 18:50
To: Ilia Lin <redacted>; linux-arm-kernel at lists.infradead.org;
linux-arm-msm at vger.kernel.org; linux-clk at vger.kernel.org;
sboyd at codeaurora.org
Cc: mark.rutland at arm.com; devicetree at vger.kernel.org;
rnayak at codeaurora.org; robh at kernel.org; will.deacon at arm.com;
amit.kucheria at linaro.org; tfinkel at codeaurora.org; ilialin at codeaurora.org;
nicolas.dechesne at linaro.org; celster at codeaurora.org
Subject: Re: [PATCH v3 07/10] clk: qcom: clk-cpu-8996: Prepare PLLs on probe

Quoting Ilia Lin (2018-02-14 05:59:49)

quoted

The PLLs must be prepared enabled during the probe to be accessible by
the OPPs. Otherwise an OPP may switch to non-enabled clock.

Sounds like an OPP problem.

And again, it could be solved by a platform specific cpufreq driver. Worth it?

quoted

Signed-off-by: Ilia Lin <redacted>
---
 drivers/clk/qcom/clk-cpu-8996.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/qcom/clk-cpu-8996.c

b/drivers/clk/qcom/clk-cpu-8996.c index 854f327..b0a3b73 100644

--- a/drivers/clk/qcom/clk-cpu-8996.c
+++ b/drivers/clk/qcom/clk-cpu-8996.c

@@ -15,7 +15,7 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
-
+#include <linux/clk-provider.h>

Please leave a newline between linux/* and local includes.

Will be changed in the next spin.

quoted

 #include "clk-alpha-pll.h"

 #define VCO(a, b, c) { \

@@ -376,6 +376,18 @@ struct clk_hw_clks {
        clk_alpha_pll_configure(&perfcl_alt_pll, regmap, &altpll_config);
        clk_alpha_pll_configure(&pwrcl_alt_pll, regmap,

&altpll_config);

+       /* Enable all PLLs and alt PLLs */
+       clk_prepare_enable(pwrcl_alt_pll.clkr.hw.clk);
+       clk_prepare_enable(perfcl_alt_pll.clkr.hw.clk);
+       clk_prepare_enable(pwrcl_pll.clkr.hw.clk);
+       clk_prepare_enable(perfcl_pll.clkr.hw.clk);

And this can't be done by the cpufreq-dt driver?

Are you suggesting changing the cpufreq-dt as well?

quoted

+
+       /* Set initial boot frequencies for power/perf PLLs */
+       clk_set_rate(pwrcl_alt_pll.clkr.hw.clk, 652800000);
+       clk_set_rate(perfcl_alt_pll.clkr.hw.clk, 652800000);
+       clk_set_rate(pwrcl_pll.clkr.hw.clk, 652800000);
+       clk_set_rate(perfcl_pll.clkr.hw.clk, 652800000);

We have assigned rates in DT for this.

I assumed that the clock driver can live without the OPP table and any cpufreq driver. Or do you mean adding this as parameters for the kryocc DT node?

quoted

+
        ret = clk_notifier_register(pwrcl_pmux.clkr.hw.clk, &pwrcl_pmux.nb);
        if (ret)
                return ret;