Add WDIOF_EXTERN1 and WDIOF_CARDRESET bootstatus in ast2500/ast2600
Regarding the AST2600 specification, the WDTn Timeout Status Register
(WDT10) has bit 1 reserved. Bit 1 of the status register indicates
on ast2500 if the boot was from the second boot source.
It does not indicate that the most recent reset was triggered by
the watchdog. The code should just be changed to set WDIOF_CARDRESET
if bit 0 of the status register is set.
Include SCU register to veriy WDIOF_EXTERN1 in ast2600 SCU74 or
ast2500 SCU3C when bit1 is set.
Change Log:
v5 -> v6
- Fixed missing WDT_TIMEOUT_STATUS_EVENT.
v4 -> v5
- Revert indentation.
v3 -> v4
- Add error handling for syscon_regmap_lookup_by_phandle and
regmap_read.
v2 -> v3
- Fixed WDIOF_CARDRESET status bit check and added support
for WDIOF_EXTERN1 on ast2500 and ast2600.
v1 -> v2
- Add comment and support WDIOF_CARDRESET in ast2600
v1
- Patch 0001 - Add WDIOF_EXTERN1 bootstatus
---
Peter Yin (4):
ARM: dts: aspeed: Add the AST2500 WDT with SCU register
ARM: dts: aspeed: Add the AST2600 WDT with SCU register
dt-bindings: watchdog: aspeed-wdt: Add aspeed,scu
drivers: watchdog: ast2500 and ast2600 support bootstatus
.../bindings/watchdog/aspeed-wdt.txt | 4 +++
arch/arm/boot/dts/aspeed/aspeed-g5.dtsi | 3 ++
arch/arm/boot/dts/aspeed/aspeed-g6.dtsi | 4 +++
drivers/watchdog/aspeed_wdt.c | 35 ++++++++++++++++---
4 files changed, 42 insertions(+), 4 deletions(-)
--
2.25.1
The AST2600 Watchdog Timer (WDT) references
the System Control Unit (SCU) register for its operation.
Signed-off-by: Peter Yin <[email protected]>
---
arch/arm/boot/dts/aspeed/aspeed-g6.dtsi | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi b/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi
index ead835fca657..b47850f0dca0 100644
--- a/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi
+++ b/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi
@@ -557,23 +557,27 @@ uart5: serial@1e784000 {
wdt1: watchdog@1e785000 {
compatible = "aspeed,ast2600-wdt";
reg = <0x1e785000 0x40>;
+ aspeed,scu = <&syscon>;
};
wdt2: watchdog@1e785040 {
compatible = "aspeed,ast2600-wdt";
reg = <0x1e785040 0x40>;
+ aspeed,scu = <&syscon>;
status = "disabled";
};
wdt3: watchdog@1e785080 {
compatible = "aspeed,ast2600-wdt";
reg = <0x1e785080 0x40>;
+ aspeed,scu = <&syscon>;
status = "disabled";
};
wdt4: watchdog@1e7850c0 {
compatible = "aspeed,ast2600-wdt";
reg = <0x1e7850C0 0x40>;
+ aspeed,scu = <&syscon>;
status = "disabled";
};
--
2.25.1
Add WDIOF_EXTERN1 and WDIOF_CARDRESET bootstatus in ast2600
Regarding the AST2600 specification, the WDTn Timeout Status Register
(WDT10) has bit 1 reserved. Bit 1 of the status register indicates
on ast2500 if the boot was from the second boot source.
It does not indicate that the most recent reset was triggered by
the watchdog. The code should just be changed to set WDIOF_CARDRESET
if bit 0 of the status register is set.
Include SCU register to veriy WDIOF_EXTERN1 in ast2600 SCU74 or
ast2500 SCU3C when bit1 is set.
Signed-off-by: Peter Yin <[email protected]>
---
drivers/watchdog/aspeed_wdt.c | 35 +++++++++++++++++++++++++++++++----
1 file changed, 31 insertions(+), 4 deletions(-)
diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index b4773a6aaf8c..0e7ef860cbdc 100644
--- a/drivers/watchdog/aspeed_wdt.c
+++ b/drivers/watchdog/aspeed_wdt.c
@@ -11,10 +11,12 @@
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/kstrtox.h>
+#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
#include <linux/watchdog.h>
static bool nowayout = WATCHDOG_NOWAYOUT;
@@ -77,11 +79,19 @@ MODULE_DEVICE_TABLE(of, aspeed_wdt_of_table);
#define WDT_TIMEOUT_STATUS 0x10
#define WDT_TIMEOUT_STATUS_IRQ BIT(2)
#define WDT_TIMEOUT_STATUS_BOOT_SECONDARY BIT(1)
+#define WDT_TIMEOUT_STATUS_EVENT BIT(0)
#define WDT_CLEAR_TIMEOUT_STATUS 0x14
#define WDT_CLEAR_TIMEOUT_AND_BOOT_CODE_SELECTION BIT(0)
#define WDT_RESET_MASK1 0x1c
#define WDT_RESET_MASK2 0x20
+/*
+ * Ast2600 SCU74 bit1 is External reset flag
+ * Ast2500 SCU3C bit1 is External reset flag
+ */
+#define AST2500_SYSTEM_RESET_EVENT 0x3C
+#define AST2600_SYSTEM_RESET_EVENT 0x74
+#define EXTERN_RESET_FLAG BIT(1)
/*
* WDT_RESET_WIDTH controls the characteristics of the external pulse (if
* enabled), specifically:
@@ -330,6 +340,11 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
if (IS_ERR(wdt->base))
return PTR_ERR(wdt->base);
+ struct regmap *scu_base = syscon_regmap_lookup_by_phandle(dev->of_node,
+ "aspeed,scu");
+ if (IS_ERR(scu_base))
+ return PTR_ERR(scu_base);
+
wdt->wdd.info = &aspeed_wdt_info;
if (wdt->cfg->irq_mask) {
@@ -459,14 +474,26 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
}
status = readl(wdt->base + WDT_TIMEOUT_STATUS);
- if (status & WDT_TIMEOUT_STATUS_BOOT_SECONDARY) {
+ if (status & WDT_TIMEOUT_STATUS_EVENT)
wdt->wdd.bootstatus = WDIOF_CARDRESET;
- if (of_device_is_compatible(np, "aspeed,ast2400-wdt") ||
- of_device_is_compatible(np, "aspeed,ast2500-wdt"))
- wdt->wdd.groups = bswitch_groups;
+ if (of_device_is_compatible(np, "aspeed,ast2600-wdt")) {
+ ret = regmap_read(scu_base,
+ AST2600_SYSTEM_RESET_EVENT,
+ &status);
+ } else {
+ ret = regmap_read(scu_base,
+ AST2500_SYSTEM_RESET_EVENT,
+ &status);
+ wdt->wdd.groups = bswitch_groups;
}
+ /*
+ * Reset cause by Extern Reset
+ */
+ if (status & EXTERN_RESET_FLAG && !ret)
+ wdt->wdd.bootstatus |= WDIOF_EXTERN1;
+
dev_set_drvdata(dev, wdt);
return devm_watchdog_register_device(dev, &wdt->wdd);
--
2.25.1
Peter Yin 於 3/28/24 10:22 寫道:
> Add WDIOF_EXTERN1 and WDIOF_CARDRESET bootstatus in ast2600
>
> Regarding the AST2600 specification, the WDTn Timeout Status Register
> (WDT10) has bit 1 reserved. Bit 1 of the status register indicates
> on ast2500 if the boot was from the second boot source.
> It does not indicate that the most recent reset was triggered by
> the watchdog. The code should just be changed to set WDIOF_CARDRESET
> if bit 0 of the status register is set.
>
> Include SCU register to veriy WDIOF_EXTERN1 in ast2600 SCU74 or
> ast2500 SCU3C when bit1 is set.
>
> Signed-off-by: Peter Yin <[email protected]>
> ---
> drivers/watchdog/aspeed_wdt.c | 35 +++++++++++++++++++++++++++++++----
> 1 file changed, 31 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
> index b4773a6aaf8c..0e7ef860cbdc 100644
> --- a/drivers/watchdog/aspeed_wdt.c
> +++ b/drivers/watchdog/aspeed_wdt.c
> @@ -11,10 +11,12 @@
> #include <linux/io.h>
> #include <linux/kernel.h>
> #include <linux/kstrtox.h>
> +#include <linux/mfd/syscon.h>
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/of_irq.h>
> #include <linux/platform_device.h>
> +#include <linux/regmap.h>
> #include <linux/watchdog.h>
>
> static bool nowayout = WATCHDOG_NOWAYOUT;
> @@ -77,11 +79,19 @@ MODULE_DEVICE_TABLE(of, aspeed_wdt_of_table);
> #define WDT_TIMEOUT_STATUS 0x10
> #define WDT_TIMEOUT_STATUS_IRQ BIT(2)
> #define WDT_TIMEOUT_STATUS_BOOT_SECONDARY BIT(1)
> +#define WDT_TIMEOUT_STATUS_EVENT BIT(0)
> #define WDT_CLEAR_TIMEOUT_STATUS 0x14
> #define WDT_CLEAR_TIMEOUT_AND_BOOT_CODE_SELECTION BIT(0)
> #define WDT_RESET_MASK1 0x1c
> #define WDT_RESET_MASK2 0x20
>
> +/*
> + * Ast2600 SCU74 bit1 is External reset flag
> + * Ast2500 SCU3C bit1 is External reset flag
> + */
> +#define AST2500_SYSTEM_RESET_EVENT 0x3C
> +#define AST2600_SYSTEM_RESET_EVENT 0x74
> +#define EXTERN_RESET_FLAG BIT(1)
> /*
> * WDT_RESET_WIDTH controls the characteristics of the external pulse (if
> * enabled), specifically:
> @@ -330,6 +340,11 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
> if (IS_ERR(wdt->base))
> return PTR_ERR(wdt->base);
>
> + struct regmap *scu_base = syscon_regmap_lookup_by_phandle(dev->of_node,
> + "aspeed,scu");
> + if (IS_ERR(scu_base))
> + return PTR_ERR(scu_base);
> +
> wdt->wdd.info = &aspeed_wdt_info;
>
> if (wdt->cfg->irq_mask) {
> @@ -459,14 +474,26 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
> }
>
> status = readl(wdt->base + WDT_TIMEOUT_STATUS);
> - if (status & WDT_TIMEOUT_STATUS_BOOT_SECONDARY) {
> + if (status & WDT_TIMEOUT_STATUS_EVENT)
> wdt->wdd.bootstatus = WDIOF_CARDRESET;
>
> - if (of_device_is_compatible(np, "aspeed,ast2400-wdt") ||
> - of_device_is_compatible(np, "aspeed,ast2500-wdt"))
> - wdt->wdd.groups = bswitch_groups;
> + if (of_device_is_compatible(np, "aspeed,ast2600-wdt")) {
> + ret = regmap_read(scu_base,
> + AST2600_SYSTEM_RESET_EVENT,
> + &status);
> + } else {
> + ret = regmap_read(scu_base,
> + AST2500_SYSTEM_RESET_EVENT,
> + &status);
> + wdt->wdd.groups = bswitch_groups;
> }
>
> + /*
> + * Reset cause by Extern Reset
> + */
> + if (status & EXTERN_RESET_FLAG && !ret)
> + wdt->wdd.bootstatus |= WDIOF_EXTERN1;
> +
> dev_set_drvdata(dev, wdt);
>
> return devm_watchdog_register_device(dev, &wdt->wdd);
Hi Guenter,
Could you help me understand the definition of WDIOF_CARDRESET in
the kernel? If it resets the CPU, should all values be reset to default?
Should we check the POR (RstPwr Power on reset SRST# flag) flag in SCU
0x74 register bit 0 in ast2600?
On Wed, Apr 10, 2024 at 12:28:44AM +0800, PeterYin wrote:
[ ... ]
>
> Hi Guenter,
> Could you help me understand the definition of WDIOF_CARDRESET in the
> kernel? If it resets the CPU, should all values be reset to default? Should
Documentation/watchdog/watchdog-api.rst says:
"Card previously reset the CPU"
This is a bit historic and was probably defined when watchdogs were
not typically integrated. The appropriate description, applied to
current watchdog devices, would be something like "The most recent
reset was triggered by this watchdog".
Not sure I understand "If it resets the CPU...". It doesn't _do_
anything, it just reports if the most recent reset was triggered
by the watchdog.
> we check the POR (RstPwr Power on reset SRST# flag) flag in SCU 0x74
> register bit 0 in ast2600?
>
Only if it indicates that the most recent reset was triggered by the
watchdog.
Guenter