Re: [PATCH 2/3] pmdomain: mediatek: Add bus protect control flow for MT8189

[Matthias Brugger <matthias.bgg@gmail.com>]

On 02/02/2026 07:48, irving.ch.lin wrote:
> 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>

Reviewed-by: Matthias Brugger <matthias.bgg@gmail.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 0f0662676c07..3eeb0dabf7d7 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) !=
> +		    (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,		\