Re: [PATCH v3 20/21] pmdomain: mediatek: Add bus protect control flow for MT8189

AngeloGioacchino Del Regno
2025-11-07T10:36:48Z

Il 06/11/25 13:42, irving.ch.lin ha scritto:
> From: Irving-CH Lin <irving-ch.lin@mediatek.com>
>
> In MT8189 mminfra power domain, the bus protect policy separates
> into two parts, one is set before subsys clocks enabled, and another
> need to enable after subsys clocks enable.
>
> Signed-off-by: Irving-CH Lin <irving-ch.lin@mediatek.com>
> ---
> drivers/pmdomain/mediatek/mtk-pm-domains.c | 31 ++++++++++++++++++----
> drivers/pmdomain/mediatek/mtk-pm-domains.h | 5 ++++
> 2 files changed, 31 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pmdomain/mediatek/mtk-pm-domains.c b/drivers/pmdomain/mediatek/mtk-pm-domains.c
> index 164c6b519af3..222846e52daf 100644
> --- a/drivers/pmdomain/mediatek/mtk-pm-domains.c
> +++ b/drivers/pmdomain/mediatek/mtk-pm-domains.c
> @@ -250,7 +250,7 @@ static int scpsys_bus_protect_set(struct scpsys_domain *pd,
> MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
> }
>
> -static int scpsys_bus_protect_enable(struct scpsys_domain *pd)
> +static int scpsys_bus_protect_enable(struct scpsys_domain *pd, u8 flags)
> {
> for (int i = 0; i < SPM_MAX_BUS_PROT_DATA; i++) {
> const struct scpsys_bus_prot_data *bpd = &pd->data->bp_cfg[i];
> @@ -259,6 +259,10 @@ static int scpsys_bus_protect_enable(struct scpsys_domain *pd)
> if (!bpd->bus_prot_set_clr_mask)
> break;
>
> + if ((bpd->flags & BUS_PROT_IGNORE_SUBCLK) !=
> + (flags & BUS_PROT_IGNORE_SUBCLK))
> + continue;
> +
> if (bpd->flags & BUS_PROT_INVERTED)
> ret = scpsys_bus_protect_clear(pd, bpd);
> else
> @@ -270,7 +274,7 @@ static int scpsys_bus_protect_enable(struct scpsys_domain *pd)
> return 0;
> }
>
> -static int scpsys_bus_protect_disable(struct scpsys_domain *pd)
> +static int scpsys_bus_protect_disable(struct scpsys_domain *pd, u8 flags)
> {
> for (int i = SPM_MAX_BUS_PROT_DATA - 1; i >= 0; i--) {
> const struct scpsys_bus_prot_data *bpd = &pd->data->bp_cfg[i];
> @@ -279,6 +283,10 @@ static int scpsys_bus_protect_disable(struct scpsys_domain *pd)
> if (!bpd->bus_prot_set_clr_mask)
> continue;
>
> + if ((bpd->flags & BUS_PROT_IGNORE_SUBCLK) !=

Is that the right name for this flag?

As far as I understand, you have to set bus protection in two steps, right?
So in the first step you're setting bus protection for the MM_INFRA and for
MM_INFRA_2ND - and in the second step you're setting MM_INFRA_IGN and 2_IGN.

So the first step (the prots with BUS_PROT_IGNORE_SUBCLK) unlocks SUBSYS clks
and SRAM ISO access, the second one does the rest.

I think that a better name for this, at this point would be...

if ((bpd->flags & local_flags) & BUS_PROT_SRAM_PROTECTION)
continue;

What do you think?

Regards,
Angelo

> + (flags & BUS_PROT_IGNORE_SUBCLK))
> + continue;
> +
> if (bpd->flags & BUS_PROT_INVERTED)
> ret = scpsys_bus_protect_set(pd, bpd);
> else
> @@ -632,6 +640,15 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
> if (ret)
> goto err_pwr_ack;
>
> + /*
> + * In MT8189 mminfra power domain, the bus protect policy separates
> + * into two parts, one is set before subsys clocks enabled, and another
> + * need to enable after subsys clocks enable.
> + */
> + ret = scpsys_bus_protect_disable(pd, BUS_PROT_IGNORE_SUBCLK);
> + if (ret < 0)
> + goto err_pwr_ack;
> +
> /*
> * In few Mediatek platforms(e.g. MT6779), the bus protect policy is
> * stricter, which leads to bus protect release must be prior to bus
> @@ -648,7 +665,7 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
> if (ret < 0)
> goto err_disable_subsys_clks;
>
> - ret = scpsys_bus_protect_disable(pd);
> + ret = scpsys_bus_protect_disable(pd, 0);
> if (ret < 0)
> goto err_disable_sram;
>
> @@ -662,7 +679,7 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
> return 0;
>
> err_enable_bus_protect:
> - scpsys_bus_protect_enable(pd);
> + scpsys_bus_protect_enable(pd, 0);
> err_disable_sram:
> scpsys_sram_disable(pd);
> err_disable_subsys_clks:
> @@ -683,7 +700,7 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
> bool tmp;
> int ret;
>
> - ret = scpsys_bus_protect_enable(pd);
> + ret = scpsys_bus_protect_enable(pd, 0);
> if (ret < 0)
> return ret;
>
> @@ -697,6 +714,10 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
>
> clk_bulk_disable_unprepare(pd->num_subsys_clks, pd->subsys_clks);
>
> + ret = scpsys_bus_protect_enable(pd, BUS_PROT_IGNORE_SUBCLK);
> + if (ret < 0)
> + return ret;
> +
> if (MTK_SCPD_CAPS(pd, MTK_SCPD_MODEM_PWRSEQ))
> scpsys_modem_pwrseq_off(pd);
> else
> diff --git a/drivers/pmdomain/mediatek/mtk-pm-domains.h b/drivers/pmdomain/mediatek/mtk-pm-domains.h
> index f608e6ec4744..a5dca24cbc2f 100644
> --- a/drivers/pmdomain/mediatek/mtk-pm-domains.h
> +++ b/drivers/pmdomain/mediatek/mtk-pm-domains.h
> @@ -56,6 +56,7 @@ enum scpsys_bus_prot_flags {
> BUS_PROT_REG_UPDATE = BIT(1),
> BUS_PROT_IGNORE_CLR_ACK = BIT(2),
> BUS_PROT_INVERTED = BIT(3),
> + BUS_PROT_IGNORE_SUBCLK = BIT(4),
> };
>
> enum scpsys_bus_prot_block {
> @@ -95,6 +96,10 @@ enum scpsys_bus_prot_block {
> _BUS_PROT(_hwip, _mask, _set, _clr, _mask, _sta, \
> BUS_PROT_REG_UPDATE)
>
> +#define BUS_PROT_WR_IGN_SUBCLK(_hwip, _mask, _set, _clr, _sta) \
> + _BUS_PROT(_hwip, _mask, _set, _clr, _mask, _sta, \
> + BUS_PROT_IGNORE_CLR_ACK | BUS_PROT_IGNORE_SUBCLK)
> +
> #define BUS_PROT_INFRA_UPDATE_TOPAXI(_mask) \
> BUS_PROT_UPDATE(INFRA, _mask, \
> INFRA_TOPAXI_PROTECTEN, \