On Thu, Sep 29, 2022 at 02:17:03PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
>
> It is possible that when remote processor crash, the communication
> channel will be broken with garbage value in mailbox, such as
> when Linux is issuing a message through mailbox, remote processor
> crashes, we need free & rebuild the mailbox channels to make sure
> no garbage value in mailbox channels.
>
> So move the request/free to start/stop for managing remote procesosr in
> Linux, move to attach/detach for remote processor is out of control of
> Linux.
>
> Previous, we just request mbox when attach for CM4 boot early before
> Linux, but if mbox defer probe, remoteproc core will do resource cleanup
> and corrupt resource table for later probe.
>
> So move request mbox ealier and still keep mbox request when attach
> for self recovery case, but keep a check when request/free mbox.
>
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> ---
> drivers/remoteproc/imx_rproc.c | 26 +++++++++++++++++++++++---
> 1 file changed, 23 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
> index 8175c4c9aa22..bece44b46719 100644
> --- a/drivers/remoteproc/imx_rproc.c
> +++ b/drivers/remoteproc/imx_rproc.c
> @@ -84,6 +84,8 @@ struct imx_rproc_mem {
> #define ATT_CORE_MASK 0xffff
> #define ATT_CORE(I) BIT((I))
>
> +static int imx_rproc_xtr_mbox_init(struct rproc *rproc);
> +static void imx_rproc_free_mbox(struct rproc *rproc);
> static int imx_rproc_detach_pd(struct rproc *rproc);
>
> struct imx_rproc {
> @@ -357,6 +359,10 @@ static int imx_rproc_start(struct rproc *rproc)
> struct arm_smccc_res res;
> int ret;
>
> + ret = imx_rproc_xtr_mbox_init(rproc);
> + if (ret)
> + return ret;
> +
> switch (dcfg->method) {
> case IMX_RPROC_MMIO:
> ret = regmap_update_bits(priv->regmap, dcfg->src_reg, dcfg->src_mask,
> @@ -407,6 +413,8 @@ static int imx_rproc_stop(struct rproc *rproc)
>
> if (ret)
> dev_err(dev, "Failed to stop remote core\n");
> + else
> + imx_rproc_free_mbox(rproc);
>
> return ret;
> }
> @@ -592,7 +600,7 @@ static void imx_rproc_kick(struct rproc *rproc, int vqid)
>
> static int imx_rproc_attach(struct rproc *rproc)
> {
> - return 0;
> + return imx_rproc_xtr_mbox_init(rproc);
> }
>
> static struct resource_table *imx_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz)
> @@ -720,6 +728,9 @@ static int imx_rproc_xtr_mbox_init(struct rproc *rproc)
> struct device *dev = priv->dev;
> struct mbox_client *cl;
>
> + if (priv->tx_ch && priv->rx_ch)
> + return 0;
> +
Why is this needed? The remoteproc core's state machine driven by rproc->state
guarantees that imx_rproc_start(), imx_rproc_stop() and imx_rproc_attach are not
called more than once.
And why is imx_rproc_xtr_mbox_init() in imx_rproc_probe() not removed?
> if (!of_get_property(dev->of_node, "mbox-names", NULL))
> return 0;
>
> @@ -749,8 +760,15 @@ static void imx_rproc_free_mbox(struct rproc *rproc)
> {
> struct imx_rproc *priv = rproc->priv;
>
> - mbox_free_channel(priv->tx_ch);
> - mbox_free_channel(priv->rx_ch);
> + if (priv->tx_ch) {
> + mbox_free_channel(priv->tx_ch);
> + priv->tx_ch = NULL;
> + }
> +
> + if (priv->rx_ch) {
> + mbox_free_channel(priv->rx_ch);
> + priv->rx_ch = NULL;
> + }
> }
>
> static void imx_rproc_put_scu(struct rproc *rproc)
> @@ -779,6 +797,8 @@ static int imx_rproc_partition_notify(struct notifier_block *nb,
> if (!((event & BIT(priv->rproc_pt)) && (*(u8 *)group == IMX_SC_IRQ_GROUP_REBOOTED)))
> return 0;
>
> + imx_rproc_free_mbox(priv->rproc);
Why putting this here when it will be called again in imx_rproc_stop()? If you
need it for the attached scenario, create imx_rproc_detach() and add it there.
> +
> rproc_report_crash(priv->rproc, RPROC_WATCHDOG);
>
> pr_info("Partition%d reset!\n", priv->rproc_pt);
> --
> 2.37.1
>
