Re: [PATCH v2] clk: starfive: jh7100: Use clk_hw for external input clocks

From: Samuel Holland
Date: Wed Mar 20 2024 - 11:00:02 EST


Hi Geert,

On 2024-03-20 9:28 AM, Geert Uytterhoeven wrote:
> On Wed, Mar 20, 2024 at 2:31 PM Samuel Holland
> <samuel.holland@xxxxxxxxxx> wrote:
>> On 2024-03-20 6:24 AM, Geert Uytterhoeven wrote:
>>> The Starfive JH7100 clock driver does not use the DT "clocks" property
>>> to find the external main input clock, but instead relies on the name of
>>> the actual clock provider ("osc_sys"). This is fragile, and caused
>>> breakage when sanitizing clock node names in DTS.
>>>
>>> Fix this by obtaining the external main input clock using
>>> devm_clk_get(), and passing the returned clk_hw object to
>>> devm_clk_hw_register_fixed_factor_parent_hw().
>>>
>>> While name-based look-up of the other external input clocks works as-is,
>>> convert them to a similar clk_hw-based scheme to increase uniformity,
>>> and to decrease the number of name-based look-ups.
>>>
>>> Fixes: f03606470886 ("riscv: dts: starfive: replace underscores in node names")
>>> Fixes: 4210be668a09ee20 ("clk: starfive: Add JH7100 clock generator driver")
>>> Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
>
>
>>> --- a/drivers/clk/starfive/clk-starfive-jh7100.c
>>> +++ b/drivers/clk/starfive/clk-starfive-jh7100.c
>
>>> @@ -284,8 +293,11 @@ static struct clk_hw *jh7100_clk_get(struct of_phandle_args *clkspec, void *data
>>>
>>> static int __init clk_starfive_jh7100_probe(struct platform_device *pdev)
>>> {
>>> + static const char *jh7100_ext_clk[EXT_NUM_CLKS] =
>>> + { "osc_sys", "osc_aud", "gmac_rmii_ref", "gmac_gr_mii_rxclk" };
>>
>> This should be __initconst. Otherwise:
>
> With
>
> - static const char *jh7100_ext_clk[EXT_NUM_CLKS] =
> + static const char *jh7100_ext_clk[EXT_NUM_CLKS] __initconst =
>
> I get:
>
> drivers/clk/starfive/clk-starfive-jh7100.c: In function
> ‘clk_starfive_jh7100_probe’:
> drivers/clk/starfive/clk-starfive-jh7100.c:35:37: error:
> ‘jh7100_clk_data’ causes a section type conflict with ‘jh7100_ext_clk’
> 35 | static const struct jh71x0_clk_data jh7100_clk_data[]
> __initconst = {
> | ^~~~~~~~~~~~~~~
> drivers/clk/starfive/clk-starfive-jh7100.c:296:28: note:
> ‘jh7100_ext_clk’ was declared here
> 296 | static const char *jh7100_ext_clk[EXT_NUM_CLKS]
> __initconst =
> | ^~~~~~~~~~~~~~
>
> which is a bit strange...
> What am I missing?

I think you need to add another "const" covering the array itself:

static const char *const jh7100_ext_clk[EXT_NUM_CLKS] __initconst =

Regards,
Samuel