Re: [PATCH v3 2/2] remoteproc: k3-r5: Do not allow core1 to power up before core0 via sysfs

[Christophe JAILLET <christophe.jaillet@wanadoo.fr>]

Le 30/04/2024 à 12:53, Beleswar Padhi a écrit :
> PSC controller has a limitation that it can only power-up the second
> core when the first core is in ON state. Power-state for core0 should be
> equal to or higher than core1.
> 
> Therefore, prevent core1 from powering up before core0 during the start
> process from sysfs. Similarly, prevent core0 from shutting down before
> core1 has been shut down from sysfs.
> 
> Fixes: 6dedbd1d5443 ("remoteproc: k3-r5: Add a remoteproc driver for R5F subsystem")
> 
> Signed-off-by: Beleswar Padhi <b-padhi@ti.com>
> ---
>   drivers/remoteproc/ti_k3_r5_remoteproc.c | 23 +++++++++++++++++++++--
>   1 file changed, 21 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/remoteproc/ti_k3_r5_remoteproc.c b/drivers/remoteproc/ti_k3_r5_remoteproc.c
> index 6d6afd6beb3a..1799b4f6d11e 100644
> --- a/drivers/remoteproc/ti_k3_r5_remoteproc.c
> +++ b/drivers/remoteproc/ti_k3_r5_remoteproc.c
> @@ -548,7 +548,7 @@ static int k3_r5_rproc_start(struct rproc *rproc)
>   	struct k3_r5_rproc *kproc = rproc->priv;
>   	struct k3_r5_cluster *cluster = kproc->cluster;
>   	struct device *dev = kproc->dev;
> -	struct k3_r5_core *core;
> +	struct k3_r5_core *core0, *core;
>   	u32 boot_addr;
>   	int ret;
>   
> @@ -574,6 +574,15 @@ static int k3_r5_rproc_start(struct rproc *rproc)
>   				goto unroll_core_run;
>   		}
>   	} else {
> +		/* do not allow core 1 to start before core 0 */
> +		core0 = list_first_entry(&cluster->cores, struct k3_r5_core,
> +					 elem);
> +		if (core != core0 && core0->rproc->state == RPROC_OFFLINE) {
> +			dev_err(dev, "%s: can not start core 1 before core 0\n",
> +				__func__);
> +			return -EPERM;
> +		}
> +
>   		ret = k3_r5_core_run(core);
>   		if (ret)
>   			goto put_mbox;
> @@ -619,7 +628,8 @@ static int k3_r5_rproc_stop(struct rproc *rproc)
>   {
>   	struct k3_r5_rproc *kproc = rproc->priv;
>   	struct k3_r5_cluster *cluster = kproc->cluster;
> -	struct k3_r5_core *core = kproc->core;
> +	struct device *dev = kproc->dev;
> +	struct k3_r5_core *core1, *core = kproc->core;
>   	int ret;
>   
>   	/* halt all applicable cores */
> @@ -632,6 +642,15 @@ static int k3_r5_rproc_stop(struct rproc *rproc)
>   			}
>   		}
>   	} else {
> +		/* do not allow core 0 to stop before core 1 */
> +		core1 = list_last_entry(&cluster->cores, struct k3_r5_core,
> +					elem);
> +		if (core != core1 && core1->rproc->state != RPROC_OFFLINE) {
> +			dev_err(dev, "%s: can not stop core 0 before core 1\n",
> +				__func__);
> +			return -EPERM;

Hi,

this patch has already reached -next, but should this "return -EPERM;" be :
	ret = -EPERM;
	goto put_mbox;

instead?

CJ

> +		}
> +
>   		ret = k3_r5_core_halt(core);
>   		if (ret)
>   			goto out;