linux-kernel - Re: [PATCH 07/12] soc: mediatek: pm-domains: Add extra sram control

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Message-ID: <277b1656-4a64-4fdd-865d-88cf253b7b0e@suse.com>
Date:   Thu, 10 Sep 2020 20:27:32 +0200
From:   Matthias Brugger <mbrugger@...e.com>
To:     Enric Balletbo i Serra <enric.balletbo@...labora.com>,
        linux-kernel@...r.kernel.org
Cc:     Collabora Kernel ML <kernel@...labora.com>, fparent@...libre.com,
        matthias.bgg@...il.com, drinkcat@...omium.org, hsinyi@...omium.org,
        weiyi.lu@...iatek.com, linux-arm-kernel@...ts.infradead.org,
        linux-mediatek@...ts.infradead.org
Subject: Re: [PATCH 07/12] soc: mediatek: pm-domains: Add extra sram control



On 10/09/2020 19:28, Enric Balletbo i Serra wrote:
> From: Matthias Brugger <mbrugger@...e.com>
> 
> For some power domains like vpu_core on MT8183 whose sram need to do clock
> and internal isolation while power on/off sram. We add a cap
> "MTK_SCPD_SRAM_ISO" to judge if we need to do the extra sram isolation
> control or not.
> 
> Signed-off-by: Weiyi Lu <weiyi.lu@...iatek.com>
> Signed-off-by: Matthias Brugger <mbrugger@...e.com>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@...labora.com>
> ---
> 
>   drivers/soc/mediatek/mtk-pm-domains.c | 22 ++++++++++++++++++++--
>   1 file changed, 20 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/soc/mediatek/mtk-pm-domains.c b/drivers/soc/mediatek/mtk-pm-domains.c
> index 3aa430a60602..0802eccc3a0b 100644
> --- a/drivers/soc/mediatek/mtk-pm-domains.c
> +++ b/drivers/soc/mediatek/mtk-pm-domains.c
> @@ -21,6 +21,7 @@
>   
>   #define MTK_SCPD_ACTIVE_WAKEUP		BIT(0)
>   #define MTK_SCPD_FWAIT_SRAM		BIT(1)
> +#define MTK_SCPD_SRAM_ISO		BIT(2)
>   #define MTK_SCPD_CAPS(_scpd, _x)	((_scpd)->data->caps & (_x))
>   
>   #define SPM_VDE_PWR_CON			0x0210
> @@ -42,6 +43,8 @@
>   #define PWR_ON_BIT			BIT(2)
>   #define PWR_ON_2ND_BIT			BIT(3)
>   #define PWR_CLK_DIS_BIT			BIT(4)
> +#define PWR_SRAM_CLKISO_BIT		BIT(5)
> +#define PWR_SRAM_ISOINT_B_BIT		BIT(6)
>   
>   #define PWR_STATUS_DISP			BIT(3)
>   #define PWR_STATUS_MFG			BIT(4)
> @@ -162,6 +165,14 @@ static int scpsys_sram_enable(struct scpsys_domain *pd, void __iomem *ctl_addr)
>   	if (ret < 0)
>   		return ret;
>   
> +	if (MTK_SCPD_CAPS(pd, MTK_SCPD_SRAM_ISO))	{
> +		val = readl(ctl_addr) | PWR_SRAM_ISOINT_B_BIT;
> +		writel(val, ctl_addr);
> +		udelay(1);
> +		val &= ~PWR_SRAM_CLKISO_BIT;
> +		writel(val, ctl_addr);
> +	}
> +
>   	return 0;
>   }
>   
> @@ -171,8 +182,15 @@ static int scpsys_sram_disable(struct scpsys_domain *pd, void __iomem *ctl_addr)
>   	u32 val;
>   	int tmp;
>   
> -	val = readl(ctl_addr);
> -	val |= pd->data->sram_pdn_bits;
> +	if (MTK_SCPD_CAPS(pd, MTK_SCPD_SRAM_ISO))	{
> +		val = readl(ctl_addr) | PWR_SRAM_CLKISO_BIT;
> +		writel(val, ctl_addr);
> +		val &= ~PWR_SRAM_ISOINT_B_BIT;
> +		writel(val, ctl_addr);
> +		udelay(1);
> +	}
> +
> +	val = readl(ctl_addr) | pd->data->sram_pdn_bits;

Nit, I'd prefer:
val = readl(ctl_addr);
val |= pd->data->sram_pdn_bits;


>   	writel(val, ctl_addr);
>   
>   	/* Either wait until SRAM_PDN_ACK all 1 or 0 */
>