[PATCH v3 20/21] pmdomain: mediatek: Add bus protect control flow for MT8189
Irving-CH Lin (林建弘)
Irving-CH.Lin at mediatek.com
Wed Dec 10 02:30:23 PST 2025
Hi Angelo,
On Fri, 2025-11-07 at 11:36 +0100, AngeloGioacchino Del Regno wrote:
>
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>
> Il 06/11/25 13:42, irving.ch.lin ha scritto:
> > From: Irving-CH Lin <irving-ch.lin at 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 at 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
>
Yes, the purpose is to set bus with two steps:
In general case, bus protection needs to control after subsys clock
enabled. But on MT8189 MM_INFRA subsys, some bus protection set before
subsys clock enabled.
So here i name bus protection setting w/o subsys clock as
IGNORE_SUBCLK.
thanks
BR,
irving
> > + (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, \
>
>
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