On Fri 20 Nov 21:20 CST 2020, Suman Anna wrote:
> A new API, rproc_set_firmware() is added to allow the remoteproc platform
> drivers and remoteproc client drivers to be able to configure a custom
> firmware name that is different from the default name used during
> remoteproc registration. This function is being introduced to provide
> a kernel-level equivalent of the current sysfs interface to remoteproc
> client drivers, and can only change firmwares when the remoteproc is
> offline. This allows some remoteproc drivers to choose different firmwares
> at runtime based on the functionality the remote processor is providing.
> The TI PRU Ethernet driver will be an example of such usage as it
> requires to use different firmwares for different supported protocols.
>
> Also, update the firmware_store() function used by the sysfs interface
> to reuse this function to avoid code duplication.
>
> Signed-off-by: Suman Anna <s-anna@xxxxxx>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Regards,
Bjorn
> ---
> drivers/remoteproc/remoteproc_core.c | 63 +++++++++++++++++++++++++++
> drivers/remoteproc/remoteproc_sysfs.c | 33 +-------------
> include/linux/remoteproc.h | 1 +
> 3 files changed, 66 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index dab2c0f5caf0..46c2937ebea9 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1934,6 +1934,69 @@ struct rproc *rproc_get_by_phandle(phandle phandle)
> #endif
> EXPORT_SYMBOL(rproc_get_by_phandle);
>
> +/**
> + * rproc_set_firmware() - assign a new firmware
> + * @rproc: rproc handle to which the new firmware is being assigned
> + * @fw_name: new firmware name to be assigned
> + *
> + * This function allows remoteproc drivers or clients to configure a custom
> + * firmware name that is different from the default name used during remoteproc
> + * registration. The function does not trigger a remote processor boot,
> + * only sets the firmware name used for a subsequent boot. This function
> + * should also be called only when the remote processor is offline.
> + *
> + * This allows either the userspace to configure a different name through
> + * sysfs or a kernel-level remoteproc or a remoteproc client driver to set
> + * a specific firmware when it is controlling the boot and shutdown of the
> + * remote processor.
> + *
> + * Return: 0 on success or a negative value upon failure
> + */
> +int rproc_set_firmware(struct rproc *rproc, const char *fw_name)
> +{
> + struct device *dev;
> + int ret, len;
> + char *p;
> +
> + if (!rproc || !fw_name)
> + return -EINVAL;
> +
> + dev = rproc->dev.parent;
> +
> + ret = mutex_lock_interruptible(&rproc->lock);
> + if (ret) {
> + dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
> + return -EINVAL;
> + }
> +
> + if (rproc->state != RPROC_OFFLINE) {
> + dev_err(dev, "can't change firmware while running\n");
> + ret = -EBUSY;
> + goto out;
> + }
> +
> + len = strcspn(fw_name, "\n");
> + if (!len) {
> + dev_err(dev, "can't provide empty string for firmware name\n");
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + p = kstrndup(fw_name, len, GFP_KERNEL);
> + if (!p) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + kfree(rproc->firmware);
> + rproc->firmware = p;
> +
> +out:
> + mutex_unlock(&rproc->lock);
> + return ret;
> +}
> +EXPORT_SYMBOL(rproc_set_firmware);
> +
> static int rproc_validate(struct rproc *rproc)
> {
> switch (rproc->state) {
> diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
> index 3fd18a71c188..cf846caf2e1a 100644
> --- a/drivers/remoteproc/remoteproc_sysfs.c
> +++ b/drivers/remoteproc/remoteproc_sysfs.c
> @@ -159,42 +159,13 @@ static ssize_t firmware_store(struct device *dev,
> const char *buf, size_t count)
> {
> struct rproc *rproc = to_rproc(dev);
> - char *p;
> - int err, len = count;
> + int err;
>
> /* restrict sysfs operations if not allowed by remoteproc drivers */
> if (rproc->deny_sysfs_ops)
> return -EPERM;
>
> - err = mutex_lock_interruptible(&rproc->lock);
> - if (err) {
> - dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, err);
> - return -EINVAL;
> - }
> -
> - if (rproc->state != RPROC_OFFLINE) {
> - dev_err(dev, "can't change firmware while running\n");
> - err = -EBUSY;
> - goto out;
> - }
> -
> - len = strcspn(buf, "\n");
> - if (!len) {
> - dev_err(dev, "can't provide a NULL firmware\n");
> - err = -EINVAL;
> - goto out;
> - }
> -
> - p = kstrndup(buf, len, GFP_KERNEL);
> - if (!p) {
> - err = -ENOMEM;
> - goto out;
> - }
> -
> - kfree(rproc->firmware);
> - rproc->firmware = p;
> -out:
> - mutex_unlock(&rproc->lock);
> + err = rproc_set_firmware(rproc, buf);
>
> return err ? err : count;
> }
> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> index dbc3767f7d0e..6e04b99413f8 100644
> --- a/include/linux/remoteproc.h
> +++ b/include/linux/remoteproc.h
> @@ -655,6 +655,7 @@ rproc_of_resm_mem_entry_init(struct device *dev, u32 of_resm_idx, size_t len,
>
> int rproc_boot(struct rproc *rproc);
> void rproc_shutdown(struct rproc *rproc);
> +int rproc_set_firmware(struct rproc *rproc, const char *fw_name);
> void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type);
> int rproc_coredump_add_segment(struct rproc *rproc, dma_addr_t da, size_t size);
> int rproc_coredump_add_custom_segment(struct rproc *rproc,
> --
> 2.28.0
>
