Re: [RESEND PATCH v6 5/7] clk: starfive: jh7110-sys: Add PLL clocks source from DTS
From: Xingyu Wu
Date: Fri Jul 14 2023 - 04:08:07 EST
On 2023/7/13 21:15, Emil Renner Berthing wrote:
> On Tue, 4 Jul 2023 at 08:49, Xingyu Wu <xingyu.wu@xxxxxxxxxxxxxxxx> wrote:
>>
>> Modify PLL clocks source to be got from DTS or
>> the fixed factor clocks.
>>
>> Signed-off-by: Xingyu Wu <xingyu.wu@xxxxxxxxxxxxxxxx>
>> ---
>> drivers/clk/starfive/Kconfig | 1 +
>> .../clk/starfive/clk-starfive-jh7110-sys.c | 45 +++++++++++--------
>> 2 files changed, 28 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/clk/starfive/Kconfig b/drivers/clk/starfive/Kconfig
>> index 5195f7be5213..978b78ec08b1 100644
>> --- a/drivers/clk/starfive/Kconfig
>> +++ b/drivers/clk/starfive/Kconfig
>> @@ -35,6 +35,7 @@ config CLK_STARFIVE_JH7110_SYS
>> select AUXILIARY_BUS
>> select CLK_STARFIVE_JH71X0
>> select RESET_STARFIVE_JH7110 if RESET_CONTROLLER
>> + select CLK_STARFIVE_JH7110_PLL
>> default ARCH_STARFIVE
>> help
>> Say yes here to support the system clock controller on the
>> diff --git a/drivers/clk/starfive/clk-starfive-jh7110-sys.c b/drivers/clk/starfive/clk-starfive-jh7110-sys.c
>> index e6031345ef05..d56f48013388 100644
>> --- a/drivers/clk/starfive/clk-starfive-jh7110-sys.c
>> +++ b/drivers/clk/starfive/clk-starfive-jh7110-sys.c
>> @@ -7,6 +7,7 @@
>> */
>>
>> #include <linux/auxiliary_bus.h>
>> +#include <linux/clk.h>
>> #include <linux/clk-provider.h>
>> #include <linux/init.h>
>> #include <linux/io.h>
>> @@ -386,6 +387,7 @@ EXPORT_SYMBOL_GPL(jh7110_reset_controller_register);
>>
>> static int __init jh7110_syscrg_probe(struct platform_device *pdev)
>> {
>> + bool use_fixed_pll = true; /* PLL clocks use fixed factor clocks or PLL driver */
>
> nit: reverse christmas tree ordering, eg. move this below priv
>
>> struct jh71x0_clk_priv *priv;
>> unsigned int idx;
>> int ret;
>> @@ -402,28 +404,29 @@ static int __init jh7110_syscrg_probe(struct platform_device *pdev)
>> if (IS_ERR(priv->base))
>> return PTR_ERR(priv->base);
>>
>> - /*
>> - * These PLL clocks are not actually fixed factor clocks and can be
>> - * controlled by the syscon registers of JH7110. They will be dropped
>> - * and registered in the PLL clock driver instead.
>> - */
>> + if (!IS_ERR(devm_clk_get(priv->dev, "pll0_out")))
>> + use_fixed_pll = false; /* can get pll clocks from PLL driver */
>
> The devm_clk_get() variant will allocate memory for a callback to call
> clk_put() when the driver is unloaded, but proper references
> associated with the consumers of the pll0_out clock are already taken
> below. So unless we find a better way to detect if the pll references
> are specified in the device tree or not, maybe something like this
> instead:
>
Thanks. It looks more reasonable. I will follow it in next version.
> priv->pll[0] = clk_get(priv->dev, "pll0_out);
The priv->pll[] are clk_hw* struct no clk* struct and this could be failed
when building. So maybe use a temporary clk* struct.
> if (IS_ERR(priv->pll[0])) {
> /* 24MHZ -> 1000.0MHz */
> priv->pll[0] = ...
> ...
>
> } else {
> clk_put(priv->pll[0]);
> priv->pll[0] = NULL;
>
>> + /* Use fixed factor clocks if can not get the PLL clocks from DTS */
>> + if (use_fixed_pll) {
>> /* 24MHz -> 1000.0MHz */
>
> These comments are not indented with the code, which just looks weird.
Will fix.
>
>> - priv->pll[0] = devm_clk_hw_register_fixed_factor(priv->dev, "pll0_out",
>> - "osc", 0, 125, 3);
>> - if (IS_ERR(priv->pll[0]))
>> - return PTR_ERR(priv->pll[0]);
>> + priv->pll[0] = devm_clk_hw_register_fixed_factor(priv->dev, "pll0_out",
>> + "osc", 0, 125, 3);
>> + if (IS_ERR(priv->pll[0]))
>> + return PTR_ERR(priv->pll[0]);
>>
>> /* 24MHz -> 1066.0MHz */
>> - priv->pll[1] = devm_clk_hw_register_fixed_factor(priv->dev, "pll1_out",
>> - "osc", 0, 533, 12);
>> - if (IS_ERR(priv->pll[1]))
>> - return PTR_ERR(priv->pll[1]);
>> + priv->pll[1] = devm_clk_hw_register_fixed_factor(priv->dev, "pll1_out",
>> + "osc", 0, 533, 12);
>> + if (IS_ERR(priv->pll[1]))
>> + return PTR_ERR(priv->pll[1]);
>>
>> /* 24MHz -> 1188.0MHz */
>> - priv->pll[2] = devm_clk_hw_register_fixed_factor(priv->dev, "pll2_out",
>> - "osc", 0, 99, 2);
>> - if (IS_ERR(priv->pll[2]))
>> - return PTR_ERR(priv->pll[2]);
>> + priv->pll[2] = devm_clk_hw_register_fixed_factor(priv->dev, "pll2_out",
>> + "osc", 0, 99, 2);
>> + if (IS_ERR(priv->pll[2]))
>> + return PTR_ERR(priv->pll[2]);
>> + }
>>
>> for (idx = 0; idx < JH7110_SYSCLK_END; idx++) {
>> u32 max = jh7110_sysclk_data[idx].max;
>> @@ -462,8 +465,14 @@ static int __init jh7110_syscrg_probe(struct platform_device *pdev)
>> parents[i].fw_name = "tdm_ext";
>> else if (pidx == JH7110_SYSCLK_MCLK_EXT)
>> parents[i].fw_name = "mclk_ext";
>> - else
>> + else if (use_fixed_pll)
>
> else if (priv->pll[0])
Will change.
>
>> parents[i].hw = priv->pll[pidx - JH7110_SYSCLK_PLL0_OUT];
>> + else if (pidx == JH7110_SYSCLK_PLL0_OUT)
>> + parents[i].fw_name = "pll0_out";
>> + else if (pidx == JH7110_SYSCLK_PLL1_OUT)
>> + parents[i].fw_name = "pll1_out";
>> + else if (pidx == JH7110_SYSCLK_PLL2_OUT)
>> + parents[i].fw_name = "pll2_out";
>> }
>>
>> clk->hw.init = &init;
>> --
>> 2.25.1
>>
Best regards,
Xingyu Wu