Re: [PATCH 1/2] cpufreq: sun50i: add a100 cpufreq support

[Clément Péron]

Hi Shuosheng,

On Sun, 6 Dec 2020 at 21:49, Clément Péron <peron.clem@xxxxxxxxx> wrote:
>
> Hi Shuosheng,
>
> On 04/12/2020 08:09, Shuosheng Huang wrote:
> > Let's add cpufreq nvmem based for allwinner a100 soc. It's similar to h6,
> > let us use efuse_xlate to extract the differentiated part.
>
> So you introduce 2 modifications here.
> In this case it's better to have 2 patches.
> One to introduce the efuse_xlate
> And one to introduce the A100 support.
>
> Regards,
> Clement
>
> >
> > Signed-off-by: Shuosheng Huang <huangshuosheng@xxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/cpufreq/cpufreq-dt-platdev.c   |  1 +
> >   drivers/cpufreq/sun50i-cpufreq-nvmem.c | 81 ++++++++++++++++++++------
> >   2 files changed, 64 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
> > index 3776d960f405..2ebf5d9cb616 100644
> > --- a/drivers/cpufreq/cpufreq-dt-platdev.c
> > +++ b/drivers/cpufreq/cpufreq-dt-platdev.c
> > @@ -102,6 +102,7 @@ static const struct of_device_id whitelist[] __initconst = {
> >    */
> >   static const struct of_device_id blacklist[] __initconst = {
> >       { .compatible = "allwinner,sun50i-h6", },
> > +     { .compatible = "allwinner,sun50i-a100", },
> >
> >       { .compatible = "calxeda,highbank", },
> >       { .compatible = "calxeda,ecx-2000", },
> > diff --git a/drivers/cpufreq/sun50i-cpufreq-nvmem.c b/drivers/cpufreq/sun50i-cpufreq-nvmem.c
> > index 9907a165135b..044e44a763f5 100644
> > --- a/drivers/cpufreq/sun50i-cpufreq-nvmem.c
> > +++ b/drivers/cpufreq/sun50i-cpufreq-nvmem.c
> > @@ -21,21 +21,63 @@
> >
> >   #define NVMEM_MASK  0x7
> >   #define NVMEM_SHIFT 5
> > +#define SUN50I_A100_NVMEM_MASK               0xf
> > +#define SUN50I_A100_NVMEM_SHIFT              12
> > +
> > +#define SUN50I_H6_NVMEM_MASK         0x7
> > +#define SUN50I_H6_NVMEM_SHIFT                5
> > +
> > +struct sunxi_cpufreq_soc_data {
> > +     u32 (*efuse_xlate)(void *efuse);

Maybe it's better to pass the speedbin_nvmem.
And call nvmem_cell_read_u16 or nvmem_cell_read_u32 regarding the SoC.

But I'm not a Maintainer.

Clement


> > +};
> >
> >   static struct platform_device *cpufreq_dt_pdev, *sun50i_cpufreq_pdev;
> >
> > +static u32 sun50i_a100_efuse_xlate(void *efuse)
> > +{
> > +     u32 efuse_value = (*(u16 *)efuse >> SUN50I_A100_NVMEM_SHIFT) &
> > +                       SUN50I_A100_NVMEM_MASK;
> > +
> > +     switch (efuse_value) {
> > +     case 0b100:
> > +             return 2;
> > +     case 0b010:
> > +             return 1;
> > +     default:
> > +             return 0;
> > +     }
> > +}
> > +
> > +static u32 sun50i_h6_efuse_xlate(void *efuse)
> > +{
> > +     u32 efuse_value = (*(u32 *)efuse >> SUN50I_H6_NVMEM_SHIFT) &
> > +                       SUN50I_H6_NVMEM_MASK;
> > +
> > +     /*
> > +      * We treat unexpected efuse values as if the SoC was from
> > +      * the slowest bin. Expected efuse values are 1-3, slowest
> > +      * to fastest.
> > +      */
> > +     if (efuse_value >= 1 && efuse_value <= 3)
> > +             return efuse_value - 1;
> > +     else
> > +             return 0;
> > +}
> > +
> >   /**
> >    * sun50i_cpufreq_get_efuse() - Determine speed grade from efuse value
> > + * @soc_data: pointer to sunxi_cpufreq_soc_data context
> >    * @versions: Set to the value parsed from efuse
> >    *
> >    * Returns 0 if success.
> >    */
> > -static int sun50i_cpufreq_get_efuse(u32 *versions)
> > +static int sun50i_cpufreq_get_efuse(const struct sunxi_cpufreq_soc_data *soc_data,
> > +                                 u32 *versions)
> >   {
> >       struct nvmem_cell *speedbin_nvmem;
> >       struct device_node *np;
> >       struct device *cpu_dev;
> > -     u32 *speedbin, efuse_value;
> > +     u32 *speedbin;
> >       size_t len;
> >       int ret;
> >
> > @@ -68,17 +110,7 @@ static int sun50i_cpufreq_get_efuse(u32 *versions)
> >       if (IS_ERR(speedbin))
> >               return PTR_ERR(speedbin);
> >
> > -     efuse_value = (*speedbin >> NVMEM_SHIFT) & NVMEM_MASK;
> > -
> > -     /*
> > -      * We treat unexpected efuse values as if the SoC was from
> > -      * the slowest bin. Expected efuse values are 1-3, slowest
> > -      * to fastest.
> > -      */
> > -     if (efuse_value >= 1 && efuse_value <= 3)
> > -             *versions = efuse_value - 1;
> > -     else
> > -             *versions = 0;
> > +     *versions = soc_data->efuse_xlate(speedbin);
> >
> >       kfree(speedbin);
> >       return 0;
> > @@ -86,18 +118,23 @@ static int sun50i_cpufreq_get_efuse(u32 *versions)
> >
> >   static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev)
> >   {
> > +     const struct of_device_id *match;
> >       struct opp_table **opp_tables;
> >       char name[MAX_NAME_LEN];
> >       unsigned int cpu;
> >       u32 speed = 0;
> >       int ret;
> >
> > +     match = dev_get_platdata(&pdev->dev);
> > +     if (!match)
> > +             return -EINVAL;
> > +
> >       opp_tables = kcalloc(num_possible_cpus(), sizeof(*opp_tables),
> >                            GFP_KERNEL);
> >       if (!opp_tables)
> >               return -ENOMEM;
> >
> > -     ret = sun50i_cpufreq_get_efuse(&speed);
> > +     ret = sun50i_cpufreq_get_efuse(match->data, &speed);
> >       if (ret)
> >               return ret;
> >
> > @@ -163,8 +200,17 @@ static struct platform_driver sun50i_cpufreq_driver = {
> >       },
> >   };
> >
> > +static const struct sunxi_cpufreq_soc_data sun50i_a100_data = {
> > +     .efuse_xlate = sun50i_a100_efuse_xlate,
> > +};
> > +
> > +static const struct sunxi_cpufreq_soc_data sun50i_h6_data = {
> > +     .efuse_xlate = sun50i_h6_efuse_xlate,
> > +};
> > +
> >   static const struct of_device_id sun50i_cpufreq_match_list[] = {
> > -     { .compatible = "allwinner,sun50i-h6" },
> > +     { .compatible = "allwinner,sun50i-h6", .data = &sun50i_h6_data },
> > +     { .compatible = "allwinner,sun50i-a100", .data = &sun50i_a100_data >    {}
> >   };
> >
> > @@ -198,9 +244,8 @@ static int __init sun50i_cpufreq_init(void)
> >       if (unlikely(ret < 0))
> >               return ret;
> >
> > -     sun50i_cpufreq_pdev =
> > -             platform_device_register_simple("sun50i-cpufreq-nvmem",
> > -                                             -1, NULL, 0);
> > +     sun50i_cpufreq_pdev = platform_device_register_data(NULL,
> > +             "sun50i-cpufreq-nvmem", -1, match, sizeof(*match));
> >       ret = PTR_ERR_OR_ZERO(sun50i_cpufreq_pdev);
> >       if (ret == 0)
> >               return 0;
> >