Re: [PATCH V3 4/6] remoteproc: imx_rproc: support kicking Mcore from Linux for i.MX8QXP

[Mathieu Poirier]

On Tue, May 17, 2022 at 02:49:35PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
> 
> When M4 is in the same hardware partition with Cortex-A, it
> could be start/stop by Linux.
> 
> Added power domain to make sure M4 could run, it requires several power
> domains to work. Make clk always optional for i.MX8QXP, because
> SCFW handles it when power up M4 core.
> 
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> ---
>  drivers/remoteproc/imx_rproc.c | 69 +++++++++++++++++++++++++++++++++-
>  1 file changed, 67 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
> index 2e751fc90760..49cce9dd55c7 100644
> --- a/drivers/remoteproc/imx_rproc.c
> +++ b/drivers/remoteproc/imx_rproc.c
> @@ -16,6 +16,7 @@
>  #include <linux/of_reserved_mem.h>
>  #include <linux/of_device.h>
>  #include <linux/platform_device.h>
> +#include <linux/pm_domain.h>
>  #include <linux/regmap.h>
>  #include <linux/remoteproc.h>
>  #include <linux/workqueue.h>
> @@ -96,6 +97,10 @@ struct imx_rproc {
>  	struct notifier_block		rproc_nb;
>  	u32				rproc_pt;	/* partition id */
>  	u32				rsrc_id;	/* resource id */
> +	u32				entry;		/* cpu start address */
> +	int                             num_pd;
> +	struct device                   **pd_dev;
> +	struct device_link              **pd_dev_link;
>  };
>  
>  static const struct imx_rproc_att imx_rproc_att_imx93[] = {
> @@ -335,6 +340,9 @@ static int imx_rproc_start(struct rproc *rproc)
>  		arm_smccc_smc(IMX_SIP_RPROC, IMX_SIP_RPROC_START, 0, 0, 0, 0, 0, 0, &res);
>  		ret = res.a0;
>  		break;
> +	case IMX_RPROC_SCU_API:
> +		ret = imx_sc_pm_cpu_start(priv->ipc_handle, priv->rsrc_id, true, priv->entry);
> +		break;
>  	default:
>  		return -EOPNOTSUPP;
>  	}
> @@ -364,6 +372,9 @@ static int imx_rproc_stop(struct rproc *rproc)
>  		if (res.a1)
>  			dev_info(dev, "Not in wfi, force stopped\n");
>  		break;
> +	case IMX_RPROC_SCU_API:
> +		ret = imx_sc_pm_cpu_start(priv->ipc_handle, priv->rsrc_id, false, priv->entry);
> +		break;
>  	default:
>  		return -EOPNOTSUPP;
>  	}
> @@ -724,6 +735,56 @@ static int imx_rproc_partition_notify(struct notifier_block *nb,
>  	return 0;
>  }
>  
> +static int imx_rproc_attach_pd(struct imx_rproc *priv)
> +{
> +	struct device *dev = priv->dev;
> +	int ret, i;
> +
> +	priv->num_pd = of_count_phandle_with_args(dev->of_node, "power-domains",
> +						  "#power-domain-cells");
> +	if (priv->num_pd < 0)
> +		return priv->num_pd;
> +
> +	if (!priv->num_pd)
> +		return 0;
> +
> +	priv->pd_dev = devm_kmalloc_array(dev, priv->num_pd, sizeof(*priv->pd_dev), GFP_KERNEL);
> +	if (!priv->pd_dev)
> +		return -ENOMEM;
> +
> +	priv->pd_dev_link = devm_kmalloc_array(dev, priv->num_pd, sizeof(*priv->pd_dev_link),
> +					       GFP_KERNEL);
> +
> +	if (!priv->pd_dev_link)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < priv->num_pd; i++) {
> +		priv->pd_dev[i] = dev_pm_domain_attach_by_id(dev, i);
> +		if (IS_ERR(priv->pd_dev[i])) {
> +			ret = PTR_ERR(priv->pd_dev[i]);
> +			goto detach_pd;
> +		}
> +
> +		priv->pd_dev_link[i] = device_link_add(dev, priv->pd_dev[i], DL_FLAG_STATELESS |
> +						       DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
> +		if (!priv->pd_dev_link[i]) {
> +			dev_pm_domain_detach(priv->pd_dev[i], false);
> +			ret = -EINVAL;
> +			goto detach_pd;
> +		}
> +	}
> +
> +	return 0;
> +
> +detach_pd:
> +	while (--i >= 0) {
> +		device_link_del(priv->pd_dev_link[i]);
> +		dev_pm_domain_detach(priv->pd_dev[i], false);

Same here - why are these not called during driver removal and along the error
path in probe()?

> +	}
> +
> +	return ret;
> +}
> +
>  static int imx_rproc_detect_mode(struct imx_rproc *priv)
>  {
>  	struct regmap_config config = { .name = "imx-rproc" };
> @@ -758,8 +819,12 @@ static int imx_rproc_detect_mode(struct imx_rproc *priv)
>  		 * If Mcore resource is not owned by Acore partition, It is kicked by ROM,
>  		 * and Linux could only do IPC with Mcore and nothing else.
>  		 */
> -		if (imx_sc_rm_is_resource_owned(priv->ipc_handle, priv->rsrc_id))
> -			return 0;
> +		if (imx_sc_rm_is_resource_owned(priv->ipc_handle, priv->rsrc_id)) {
> +			if (of_property_read_u32(dev->of_node, "fsl,entry-address", &priv->entry))
> +				return -EINVAL;
> +
> +			return imx_rproc_attach_pd(priv);
> +		}
>  
>  		priv->rproc->state = RPROC_DETACHED;
>  		priv->rproc->recovery_disabled = true;
> -- 
> 2.25.1
>