Exynos850 WDT IP-core differs a bit from existing platforms:
- Another set of PMU registers
- Separate WDT instance for each CPU cluster, having different PMU
registers/bits
- Source clock is different from PCLK
Implement all missing features above and enable Exynos850 WDT support.
While at it, do a bit of cleaning up.
Changes in v2:
- Added patch to fail probe if no valid timeout was found, as
suggested by Guenter Roeck (03/12)
- Extracted code for separating disable/mask functions into separate
patch (06/12)
- Added patch for inverting mask register value (07/12)
- Extracted PMU cleanup code to separate patch, to ease the review and
porting (09/12)
- Added patch for removing not needed 'err' label in probe function (11/12)
- Addressed all outstanding review comments on mailing list
Sam Protsenko (12):
dt-bindings: watchdog: Require samsung,syscon-phandle for Exynos7
dt-bindings: watchdog: Document Exynos850 watchdog bindings
watchdog: s3c2410: Fail probe if can't find valid timeout
watchdog: s3c2410: Let kernel kick watchdog
watchdog: s3c2410: Make reset disable register optional
watchdog: s3c2410: Extract disable and mask code into separate
functions
watchdog: s3c2410: Implement a way to invert mask reg value
watchdog: s3c2410: Add support for WDT counter enable register
watchdog: s3c2410: Cleanup PMU related code
watchdog: s3c2410: Support separate source clock
watchdog: s3c2410: Remove superfluous err label
watchdog: s3c2410: Add Exynos850 support
.../bindings/watchdog/samsung-wdt.yaml | 47 ++-
drivers/watchdog/s3c2410_wdt.c | 289 +++++++++++++-----
2 files changed, 254 insertions(+), 82 deletions(-)
--
2.30.2
'err' label in probe function is not really need, it just returns.
Remove it and replace all 'goto' statements with actual returns in
place.
No functional change here, just a cleanup patch.
Signed-off-by: Sam Protsenko <[email protected]>
---
Changes in v2:
- (none): it's a new patch
drivers/watchdog/s3c2410_wdt.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index c733917c5470..8fdda2ede1c3 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -588,22 +588,18 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (wdt_irq == NULL) {
dev_err(dev, "no irq resource specified\n");
- ret = -ENOENT;
- goto err;
+ return -ENOENT;
}
/* get the memory region for the watchdog timer */
wdt->reg_base = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(wdt->reg_base)) {
- ret = PTR_ERR(wdt->reg_base);
- goto err;
- }
+ if (IS_ERR(wdt->reg_base))
+ return PTR_ERR(wdt->reg_base);
wdt->bus_clk = devm_clk_get(dev, "watchdog");
if (IS_ERR(wdt->bus_clk)) {
dev_err(dev, "failed to find bus clock\n");
- ret = PTR_ERR(wdt->bus_clk);
- goto err;
+ return PTR_ERR(wdt->bus_clk);
}
ret = clk_prepare_enable(wdt->bus_clk);
@@ -720,7 +716,6 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
err_bus_clk:
clk_disable_unprepare(wdt->bus_clk);
- err:
return ret;
}
--
2.30.2
When "tmr_atboot" module param is set, the watchdog is started in
driver's probe. In that case, also set WDOG_HW_RUNNING bit to let
watchdog core driver know it's running. This way watchdog core can kick
the watchdog for us (if CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED option is
enabled), until user space takes control.
WDOG_HW_RUNNING bit must be set before registering the watchdog. So the
"tmr_atboot" handling code is moved before watchdog registration, to
avoid performing the same check twice. This is also logical because
WDOG_HW_RUNNING bit makes WDT core expect actually running watchdog.
Signed-off-by: Sam Protsenko <[email protected]>
---
Changes in v2:
- Added explanation on moving the code block to commit message
- [PATCH 03/12] handles the case when tmr_atboot is present but valid
timeout wasn't found
drivers/watchdog/s3c2410_wdt.c | 26 +++++++++++++++-----------
1 file changed, 15 insertions(+), 11 deletions(-)
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 00421cf22556..0845c05034a1 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -604,6 +604,21 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt);
wdt->wdt_device.parent = dev;
+ /*
+ * If "tmr_atboot" param is non-zero, start the watchdog right now. Also
+ * set WDOG_HW_RUNNING bit, so that watchdog core can kick the watchdog.
+ *
+ * If we're not enabling the watchdog, then ensure it is disabled if it
+ * has been left running from the bootloader or other source.
+ */
+ if (tmr_atboot) {
+ dev_info(dev, "starting watchdog timer\n");
+ s3c2410wdt_start(&wdt->wdt_device);
+ set_bit(WDOG_HW_RUNNING, &wdt->wdt_device.status);
+ } else {
+ s3c2410wdt_stop(&wdt->wdt_device);
+ }
+
ret = watchdog_register_device(&wdt->wdt_device);
if (ret)
goto err_cpufreq;
@@ -612,17 +627,6 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
if (ret < 0)
goto err_unregister;
- if (tmr_atboot) {
- dev_info(dev, "starting watchdog timer\n");
- s3c2410wdt_start(&wdt->wdt_device);
- } else {
- /* if we're not enabling the watchdog, then ensure it is
- * disabled if it has been left running from the bootloader
- * or other source */
-
- s3c2410wdt_stop(&wdt->wdt_device);
- }
-
platform_set_drvdata(pdev, wdt);
/* print out a statement of readiness */
--
2.30.2
On 31/10/2021 13:22, Sam Protsenko wrote:
> When "tmr_atboot" module param is set, the watchdog is started in
> driver's probe. In that case, also set WDOG_HW_RUNNING bit to let
> watchdog core driver know it's running. This way watchdog core can kick
> the watchdog for us (if CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED option is
> enabled), until user space takes control.
>
> WDOG_HW_RUNNING bit must be set before registering the watchdog. So the
> "tmr_atboot" handling code is moved before watchdog registration, to
> avoid performing the same check twice. This is also logical because
> WDOG_HW_RUNNING bit makes WDT core expect actually running watchdog.
>
> Signed-off-by: Sam Protsenko <[email protected]>
> ---
> Changes in v2:
> - Added explanation on moving the code block to commit message
> - [PATCH 03/12] handles the case when tmr_atboot is present but valid
> timeout wasn't found
>
> drivers/watchdog/s3c2410_wdt.c | 26 +++++++++++++++-----------
> 1 file changed, 15 insertions(+), 11 deletions(-)
>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Best regards,
Krzysztof
On 31/10/2021 13:22, Sam Protsenko wrote:
> 'err' label in probe function is not really need, it just returns.
> Remove it and replace all 'goto' statements with actual returns in
> place.
>
> No functional change here, just a cleanup patch.
>
> Signed-off-by: Sam Protsenko <[email protected]>
> ---
> Changes in v2:
> - (none): it's a new patch
>
> drivers/watchdog/s3c2410_wdt.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Best regards,
Krzysztof