Re: [PATCH v3 1/2] pmdomain: imx: Fix i.MX8MP power notifier

[Frank Li <Frank.li@nxp.com>]

On Thu, Apr 09, 2026 at 04:07:17PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@nxp.com>
>
> Using imx8mm_vpu_power_notifier() for i.MX8MP is wrong, as it ungates
> the VPU clocks to provide the ADB clock, which is necessary on i.MX8MM,
> but on i.MX8MP there is a separate gate (bit 3) for the NoC. So add
> imx8mp_vpu_power_notifier() for i.MX8MP.
>
> Fixes: a1a5f15f7f6cb ("soc: imx: imx8m-blk-ctrl: add i.MX8MP VPU blk ctrl")
> Cc: stable@vger.kernel.org
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/pmdomain/imx/imx8m-blk-ctrl.c | 27 ++++++++++++++++++++++++++-
>  1 file changed, 26 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pmdomain/imx/imx8m-blk-ctrl.c b/drivers/pmdomain/imx/imx8m-blk-ctrl.c
> index 19e992d2ee3b845bc9382bcd494a5d96f9c6ac44..e13a47eeed75d7189aa15370a7bee4cceb05a1d6 100644
> --- a/drivers/pmdomain/imx/imx8m-blk-ctrl.c
> +++ b/drivers/pmdomain/imx/imx8m-blk-ctrl.c
> @@ -514,9 +514,34 @@ static const struct imx8m_blk_ctrl_domain_data imx8mp_vpu_blk_ctl_domain_data[]
>  	},
>  };
>
> +static int imx8mp_vpu_power_notifier(struct notifier_block *nb,
> +				     unsigned long action, void *data)
> +{
> +	struct imx8m_blk_ctrl *bc = container_of(nb, struct imx8m_blk_ctrl,
> +						 power_nb);
> +
> +	if (action == GENPD_NOTIFY_ON) {
> +		/*
> +		 * On power up we have no software backchannel to the GPC to
> +		 * wait for the ADB handshake to happen, so we just delay for a
> +		 * bit. On power down the GPC driver waits for the handshake.
> +		 */
> +
> +		udelay(5);
> +
> +		/* set "fuse" bits to enable the VPUs */
> +		regmap_set_bits(bc->regmap, 0x8, 0xffffffff);
> +		regmap_set_bits(bc->regmap, 0xc, 0xffffffff);
> +		regmap_set_bits(bc->regmap, 0x10, 0xffffffff);
> +		regmap_set_bits(bc->regmap, 0x14, 0xffffffff);
> +	}
> +
> +	return NOTIFY_OK;
> +}
> +
>  static const struct imx8m_blk_ctrl_data imx8mp_vpu_blk_ctl_dev_data = {
>  	.max_reg = 0x18,
> -	.power_notifier_fn = imx8mm_vpu_power_notifier,
> +	.power_notifier_fn = imx8mp_vpu_power_notifier,
>  	.domains = imx8mp_vpu_blk_ctl_domain_data,
>  	.num_domains = ARRAY_SIZE(imx8mp_vpu_blk_ctl_domain_data),
>  };
>
> --
> 2.37.1
>