Subject: Re: [PATCH 1/4] pmdomain: bcm: bcm2835-power: Prepare to support BCM2712

From: Andrea della Porta <[email-masked]>
Date: Tue, 11 Nov 2025 12:51:40 +0100

Hi Stan,

On 09:32 Wed 17 Sep     , Stanimir Varbanov wrote:
> BCM2712 has a PM block but lacks asb and rpivid_asb register
> spaces. To avoid unwanted results add a check for asb existence
> during probe and also add a new register offset for bcm2712 to
> control grafx_v3d power domain. The decision to use the new
> register is implicit - if asb register base is null then the
> driver is probed for bcm2712 (the other supported SoCs have
> asb register space).
> 
> Signed-off-by: Stanimir Varbanov <[email-masked]>
> ---
>  drivers/pmdomain/bcm/bcm2835-power.c | 17 +++++++++++++----
>  1 file changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/pmdomain/bcm/bcm2835-power.c b/drivers/pmdomain/bcm/bcm2835-power.c
> index f5289fd184d0..1d29addfe036 100644
> --- a/drivers/pmdomain/bcm/bcm2835-power.c
> +++ b/drivers/pmdomain/bcm/bcm2835-power.c
> @@ -79,6 +79,7 @@
>  #define PM_IMAGE			0x108
>  #define PM_GRAFX			0x10c
>  #define PM_PROC				0x110
> +#define PM_GRAFX_2712			0x304
>  #define PM_ENAB				BIT(12)
>  #define PM_ISPRSTN			BIT(8)
>  #define PM_H264RSTN			BIT(7)
> @@ -381,6 +382,9 @@ static int bcm2835_power_pd_power_on(struct generic_pm_domain *domain)
>  		return bcm2835_power_power_on(pd, PM_GRAFX);
>  
>  	case BCM2835_POWER_DOMAIN_GRAFX_V3D:
> +		if (!power->asb)
> +			return bcm2835_asb_power_on(pd, PM_GRAFX_2712,
> +						    0, 0, PM_V3DRSTN);
>  		return bcm2835_asb_power_on(pd, PM_GRAFX,
>  					    ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
>  					    PM_V3DRSTN);
> @@ -447,6 +451,9 @@ static int bcm2835_power_pd_power_off(struct generic_pm_domain *domain)
>  		return bcm2835_power_power_off(pd, PM_GRAFX);
>  
>  	case BCM2835_POWER_DOMAIN_GRAFX_V3D:
> +		if (!power->asb)
> +			return bcm2835_asb_power_off(pd, PM_GRAFX_2712,
> +						     0, 0, PM_V3DRSTN);
>  		return bcm2835_asb_power_off(pd, PM_GRAFX,
>  					     ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
>  					     PM_V3DRSTN);
> @@ -635,10 +642,12 @@ static int bcm2835_power_probe(struct platform_device *pdev)
>  	power->asb = pm->asb;
>  	power->rpivid_asb = pm->rpivid_asb;
>  
> -	id = readl(power->asb + ASB_AXI_BRDG_ID);
> -	if (id != BCM2835_BRDG_ID /* "BRDG" */) {
> -		dev_err(dev, "ASB register ID returned 0x%08x\n", id);
> -		return -ENODEV;
> +	if (power->asb) {
> +		id = readl(power->asb + ASB_AXI_BRDG_ID);
> +		if (id != BCM2835_BRDG_ID /* "BRDG" */) {
> +			dev_err(dev, "ASB register ID returned 0x%08x\n", id);
> +			return -ENODEV;
> +		}
>  	}
>  
>  	if (power->rpivid_asb) {
> -- 
> 2.47.0
>

Tested-by: Andrea della Porta <[email-masked]>

Cheers,
Andrea