Re: [PATCH 09/16] soc: imx: gpcv2: add support for optional resets

[Frieder Schrempf]

On 29.04.21 09:30, Peng Fan (OSS) wrote:
> From: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
>
> Normally the reset for the devices inside the power domain is
> triggered automatically from the PGC in the power-up sequencing,
> however on i.MX8MM this doesn't work for the GPU power domains.
>
> Add support for triggering the reset explicitly during the power
> up sequencing.
>
> Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> ---
>   drivers/soc/imx/gpcv2.c | 15 +++++++++++++++
>   1 file changed, 15 insertions(+)
>
> diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
> index 640f4165cfba..4a2c2a255d1a 100644
> --- a/drivers/soc/imx/gpcv2.c
> +++ b/drivers/soc/imx/gpcv2.c
> @@ -15,6 +15,7 @@
>   #include <linux/pm_runtime.h>
>   #include <linux/regmap.h>
>   #include <linux/regulator/consumer.h>
> +#include <linux/reset.h>
>   #include <linux/sizes.h>
>   #include <dt-bindings/power/imx7-power.h>
>   #include <dt-bindings/power/imx8mq-power.h>
> @@ -108,6 +109,7 @@ struct imx_pgc_domain {
>   	struct generic_pm_domain genpd;
>   	struct regmap *regmap;
>   	struct regulator *regulator;
> +	struct reset_control *reset;
>   	struct clk_bulk_data *clks;
>   	int num_clks;
>   
> @@ -163,6 +165,8 @@ static int imx_pgc_power_up(struct generic_pm_domain *genpd)
>   		goto out_regulator_disable;
>   	}
>   
> +	reset_control_assert(domain->reset);
> +
>   	if (domain->bits.pxx) {
>   		/* request the domain to power up */
>   		regmap_update_bits(domain->regmap, GPC_PU_PGC_SW_PUP_REQ,
> @@ -185,6 +189,11 @@ static int imx_pgc_power_up(struct generic_pm_domain *genpd)
>   				   GPC_PGC_CTRL_PCR, 0);
>   	}
>   
> +	/* delay for reset to propagate */
> +	udelay(5);
> +
> +	reset_control_deassert(domain->reset);
> +
>   	/* request the ADB400 to power up */
>   	if (domain->bits.hskreq) {
>   		regmap_update_bits(domain->regmap, GPC_PU_PWRHSK,
> @@ -531,11 +540,17 @@ static int imx_pgc_domain_probe(struct platform_device *pdev)
>   				      domain->voltage, domain->voltage);
>   	}
>   
> +

Spurious blank line. Otherwise:

Reviewed-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>

>   	domain->num_clks = devm_clk_bulk_get_all(domain->dev, &domain->clks);
>   	if (domain->num_clks < 0)
>   		return dev_err_probe(domain->dev, domain->num_clks,
>   				     "Failed to get domain's clocks\n");
>   
> +	domain->reset = devm_reset_control_array_get_optional_exclusive(domain->dev);
> +	if (IS_ERR(domain->reset))
> +		return dev_err_probe(domain->dev, PTR_ERR(domain->reset),
> +				     "Failed to get domain's resets\n");
> +
>   	pm_runtime_enable(domain->dev);
>   
>   	if (domain->bits.map)