diff options
| author | Antonio Borneo <antonio.borneo@foss.st.com> | 2025-05-23 11:46:56 +0200 |
|---|---|---|
| committer | Stefan Roese <stefan.roese@mailbox.org> | 2025-07-30 08:01:11 +0200 |
| commit | 6319fabe32e76d72ceb60176b63cf8a46e78d4df (patch) | |
| tree | 0c356b92f0a6623af5618fe5c05be484048200de | |
| parent | 091303c788c2360d6ec0bf1b315d160b3b556a07 (diff) | |
watchdog: arm_smc_wdt: get wdt status through SMCWD_GET_TIMELEFT
The optional SMCWD_GET_TIMELEFT command can be used to detect if
the watchdog has already been started.
See the implementation in OP-TEE secure OS [1].
At probe time, check if the watchdog is already started and then
call wdt_set_force_autostart(). This will keep U-Boot pinging the
watchdog even when the property 'u-boot,noautostart' is present.
Link: https://github.com/OP-TEE/optee_os/commit/a7f2d4bd8632 [1]
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
| -rw-r--r-- | drivers/watchdog/arm_smc_wdt.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/watchdog/arm_smc_wdt.c b/drivers/watchdog/arm_smc_wdt.c index 0ea44445700..f6854aa9ac9 100644 --- a/drivers/watchdog/arm_smc_wdt.c +++ b/drivers/watchdog/arm_smc_wdt.c @@ -46,6 +46,8 @@ static int smcwd_call(struct udevice *dev, enum smcwd_call call, return -ENODEV; if (res->a0 == PSCI_RET_INVALID_PARAMS) return -EINVAL; + if (res->a0 == PSCI_RET_DISABLED) + return -ENODATA; if (res->a0 != PSCI_RET_SUCCESS) return -EIO; @@ -99,6 +101,21 @@ static int smcwd_probe(struct udevice *dev) priv->min_timeout = res.a1; priv->max_timeout = res.a2; + /* If already started, then force u-boot to use it */ + err = smcwd_call(dev, SMCWD_GET_TIMELEFT, 0, NULL); + switch (err) { + case 0: + dev_dbg(dev, "Already started\n"); + wdt_set_force_autostart(dev); + break; + case -ENODATA: + dev_dbg(dev, "Not already started\n"); + break; + default: + /* Optional SMCWD_GET_TIMELEFT not implemented */ + break; + } + return 0; } |