Re: [PATCH v5 07/14] soc: mediatek: Refactor sram control

[Nicolas Boichat]

On Tue, Mar 19, 2019 at 4:02 PM Weiyi Lu <weiyi.lu@xxxxxxxxxxxx> wrote:
>
> Put sram enable and disable control in separate functions.
>
> Signed-off-by: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>

Refactoring looks ok, just a small comment.

Reviewed-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx>

> ---
>  drivers/soc/mediatek/mtk-scpsys.c | 79 ++++++++++++++++++++-----------
>  1 file changed, 51 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
> index 3e9be07a2627..65b734b40098 100644
> --- a/drivers/soc/mediatek/mtk-scpsys.c
> +++ b/drivers/soc/mediatek/mtk-scpsys.c
> @@ -235,12 +235,55 @@ static void scpsys_clk_disable(struct clk *clk[], int max_num)
>         }
>  }
>
> +static int scpsys_sram_enable(struct scp_domain *scpd, void __iomem *ctl_addr)
> +{
> +       u32 val;
> +       u32 pdn_ack = scpd->data->sram_pdn_ack_bits;
> +       int tmp;
> +
> +       val = readl(ctl_addr) & ~scpd->data->sram_pdn_bits;
> +       writel(val, ctl_addr);
> +
> +       /* Either wait until SRAM_PDN_ACK all 0 or have a force wait */
> +       if (MTK_SCPD_CAPS(scpd, MTK_SCPD_FWAIT_SRAM)) {
> +               /*
> +                * Currently, MTK_SCPD_FWAIT_SRAM is necessary only for
> +                * MT7622_POWER_DOMAIN_WB and thus just a trivial setup
> +                * is applied here.
> +                */
> +               usleep_range(12000, 12100);

Does the range really need to be so tight? Would 12000, 13000 also be ok?

> +       } else {
> +               /* Either wait until SRAM_PDN_ACK all 1 or 0 */
> +               int ret = readl_poll_timeout(ctl_addr, tmp,
> +                               (tmp & pdn_ack) == 0,
> +                               MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
> +               if (ret < 0)
> +                       return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static int scpsys_sram_disable(struct scp_domain *scpd, void __iomem *ctl_addr)
> +{
> +       u32 val;
> +       u32 pdn_ack = scpd->data->sram_pdn_ack_bits;
> +       int tmp;
> +
> +       val = readl(ctl_addr) | scpd->data->sram_pdn_bits;
> +       writel(val, ctl_addr);
> +
> +       /* Either wait until SRAM_PDN_ACK all 1 or 0 */
> +       return readl_poll_timeout(ctl_addr, tmp,
> +                       (tmp & pdn_ack) == pdn_ack,
> +                       MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
> +}
> +
>  static int scpsys_power_on(struct generic_pm_domain *genpd)
>  {
>         struct scp_domain *scpd = container_of(genpd, struct scp_domain, genpd);
>         struct scp *scp = scpd->scp;
>         void __iomem *ctl_addr = scp->base + scpd->data->ctl_offs;
> -       u32 pdn_ack = scpd->data->sram_pdn_ack_bits;
>         u32 val;
>         int ret, tmp;
>
> @@ -252,6 +295,7 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
>         if (ret)
>                 goto err_clk;
>
> +       /* subsys power on */
>         val = readl(ctl_addr);
>         val |= PWR_ON_BIT;
>         writel(val, ctl_addr);
> @@ -273,24 +317,9 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
>         val |= PWR_RST_B_BIT;
>         writel(val, ctl_addr);
>
> -       val &= ~scpd->data->sram_pdn_bits;
> -       writel(val, ctl_addr);
> -
> -       /* Either wait until SRAM_PDN_ACK all 0 or have a force wait */
> -       if (MTK_SCPD_CAPS(scpd, MTK_SCPD_FWAIT_SRAM)) {
> -               /*
> -                * Currently, MTK_SCPD_FWAIT_SRAM is necessary only for
> -                * MT7622_POWER_DOMAIN_WB and thus just a trivial setup is
> -                * applied here.
> -                */
> -               usleep_range(12000, 12100);
> -
> -       } else {
> -               ret = readl_poll_timeout(ctl_addr, tmp, (tmp & pdn_ack) == 0,
> -                                        MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
> -               if (ret < 0)
> -                       goto err_pwr_ack;
> -       }
> +       ret = scpsys_sram_enable(scpd, ctl_addr);
> +       if (ret < 0)
> +               goto err_pwr_ack;
>
>         if (scpd->data->bus_prot_mask) {
>                 ret = mtk_infracfg_clear_bus_protection(scp->infracfg,
> @@ -317,7 +346,6 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
>         struct scp_domain *scpd = container_of(genpd, struct scp_domain, genpd);
>         struct scp *scp = scpd->scp;
>         void __iomem *ctl_addr = scp->base + scpd->data->ctl_offs;
> -       u32 pdn_ack = scpd->data->sram_pdn_ack_bits;
>         u32 val;
>         int ret, tmp;
>
> @@ -329,17 +357,12 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
>                         goto out;
>         }
>
> -       val = readl(ctl_addr);
> -       val |= scpd->data->sram_pdn_bits;
> -       writel(val, ctl_addr);
> -
> -       /* wait until SRAM_PDN_ACK all 1 */
> -       ret = readl_poll_timeout(ctl_addr, tmp, (tmp & pdn_ack) == pdn_ack,
> -                                MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
> +       ret = scpsys_sram_disable(scpd, ctl_addr);
>         if (ret < 0)
>                 goto out;
>
> -       val |= PWR_ISO_BIT;
> +       /* subsys power off */
> +       val = readl(ctl_addr) | PWR_ISO_BIT;
>         writel(val, ctl_addr);
>
>         val &= ~PWR_RST_B_BIT;
> --
> 2.18.0
>