[PATCH v2] drivers: watchdog: ast2600 support bootstatus
PeterYin
peteryin.openbmc at gmail.com
Wed Mar 20 20:05:28 AEDT 2024
Guenter Roeck 於 3/19/24 08:46 寫道:
> On 3/17/24 22:52, Peter Yin wrote:
>> Add WDIOF_EXTERN1 and WDIOF_CARDRESET bootstatus in ast2600
>>
>> Regarding the AST2600 specification, the WDTn Timeout Status Register
>> (WDT10) has bit 1 reserved. To verify the second boot source,
>> we need to check SEC14 bit 12 and bit 13.
>> The bits 8-23 in the WDTn Timeout Status Register are the Watchdog
>> Event Count, which we can use to verify WDIOF_EXTERN1.
>>
>> Signed-off-by: Peter Yin <peteryin.openbmc at gmail.com>
>
> You'll have to separate dts and yaml file changes from driver changes.
>
>> ---
>> Change log:
>>
>> v1 -> v2
>> - Add comment and support WDIOF_CARDRESET in ast2600
>>
>> v1
>> - Patch 0001 - Add WDIOF_EXTERN1 bootstatus
>> ---
>> arch/arm/boot/dts/aspeed/aspeed-g6.dtsi | 8 ++---
>> drivers/watchdog/aspeed_wdt.c | 45 ++++++++++++++++++++++---
>> 2 files changed, 44 insertions(+), 9 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi
>> b/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi
>> index e0b44498269f..23ae7f0430e9 100644
>> --- a/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi
>> +++ b/arch/arm/boot/dts/aspeed/aspeed-g6.dtsi
>> @@ -556,24 +556,24 @@ uart5: serial at 1e784000 {
>> wdt1: watchdog at 1e785000 {
>> compatible = "aspeed,ast2600-wdt";
>> - reg = <0x1e785000 0x40>;
>> + reg = <0x1e785000 0x40>, <0x1e6f2000 0x20>;
>> };
>> wdt2: watchdog at 1e785040 {
>> compatible = "aspeed,ast2600-wdt";
>> - reg = <0x1e785040 0x40>;
>> + reg = <0x1e785040 0x40>, <0x1e6f2000 0x020>;
>> status = "disabled";
>> };
>> wdt3: watchdog at 1e785080 {
>> compatible = "aspeed,ast2600-wdt";
>> - reg = <0x1e785080 0x40>;
>> + reg = <0x1e785080 0x40>, <0x1e6f2000 0x020>;
>> status = "disabled";
>> };
>> wdt4: watchdog at 1e7850c0 {
>> compatible = "aspeed,ast2600-wdt";
>> - reg = <0x1e7850C0 0x40>;
>> + reg = <0x1e7850C0 0x40>, <0x1e6f2000 0x020>;
>> status = "disabled";
>> };
>> diff --git a/drivers/watchdog/aspeed_wdt.c
>> b/drivers/watchdog/aspeed_wdt.c
>> index b4773a6aaf8c..65118e461130 100644
>> --- a/drivers/watchdog/aspeed_wdt.c
>> +++ b/drivers/watchdog/aspeed_wdt.c
>> @@ -33,6 +33,7 @@ struct aspeed_wdt {
>> void __iomem *base;
>> u32 ctrl;
>> const struct aspeed_wdt_config *cfg;
>> + void __iomem *sec_base;
>> };
>> static const struct aspeed_wdt_config ast2400_config = {
>> @@ -82,6 +83,15 @@ MODULE_DEVICE_TABLE(of, aspeed_wdt_of_table);
>> #define WDT_RESET_MASK1 0x1c
>> #define WDT_RESET_MASK2 0x20
>> +/*
>> + * Only Ast2600 support
>> + */
>> +#define WDT_EVENT_COUNTER_MASK (0xFFF << 8)
>> +#define WDT_SECURE_ENGINE_STATUS (0x14)
>> +#define ABR_IMAGE_SOURCE BIT(12)
>> +#define ABR_IMAGE_SOURCE_SPI BIT(13)
>> +#define SECOND_BOOT_ENABLE BIT(14)
>> +
>> /*
>> * WDT_RESET_WIDTH controls the characteristics of the external
>> pulse (if
>> * enabled), specifically:
>> @@ -313,6 +323,7 @@ static int aspeed_wdt_probe(struct platform_device
>> *pdev)
>> const char *reset_type;
>> u32 duration;
>> u32 status;
>> + u32 sec_st;
>> int ret;
>> wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
>> @@ -330,6 +341,12 @@ static int aspeed_wdt_probe(struct
>> platform_device *pdev)
>> if (IS_ERR(wdt->base))
>> return PTR_ERR(wdt->base);
>> + if (of_device_is_compatible(np, "aspeed,ast2600-wdt")) {
>> + wdt->sec_base = devm_platform_ioremap_resource(pdev, 1);
>> + if (IS_ERR(wdt->sec_base))
>> + return PTR_ERR(wdt->sec_base);
>> + }
>> +
>> wdt->wdd.info = &aspeed_wdt_info;
>> if (wdt->cfg->irq_mask) {
>> @@ -459,12 +476,30 @@ static int aspeed_wdt_probe(struct
>> platform_device *pdev)
>> }
>> status = readl(wdt->base + WDT_TIMEOUT_STATUS);
>> - if (status & WDT_TIMEOUT_STATUS_BOOT_SECONDARY) {
>> - 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")) {
>> + /*
>> + * The WDTn Timeout Status Register bit 1 is reserved.
>> + * To verify the second boot source,
>> + * we need to check SEC14 bit 12 and bit 13.
>> + */
>> + sec_st = readl(wdt->sec_base + WDT_SECURE_ENGINE_STATUS);
>> + if( sec_st & SECOND_BOOT_ENABLE)
>> + if (sec_st & ABR_IMAGE_SOURCE ||
>> + sec_st & ABR_IMAGE_SOURCE_SPI)
>
> I am sure that checkpatch as something to say here. Either case, I would
> very
> much prefer a single if() statement such as
>
> if (sec_st & SECOND_BOOT_ENABLE &&
> sec_st & (ABR_IMAGE_SOURCE | ABR_IMAGE_SOURCE_SPI))
>
>> + wdt->wdd.bootstatus |= WDIOF_CARDRESET;
>> +
>> + /*
>> + * To check Watchdog Event Count for WDIOF_EXTERN1
>> + */
>> + if (status & WDT_EVENT_COUNTER_MASK) {
>> + wdt->wdd.bootstatus |= WDIOF_EXTERN1;
>> + }
>
> Unnecessary { }
>
> ... but does this really indicate that there was a reset due to some
> event ?
> This reads three 8-bit counters. Wouldn't it make more sense to check bit 0
> instead ?
>
> I am also not sure if reading the watchdog status from
> WDT_SECURE_ENGINE_STATUS
> adds any value over the status reported in the watchdog status register.
> You'll have to explain why the added complexity is necessary or even adds
> value.
>
> Never mind, though ...
>
> Looking into the datasheets, the current code is quite completely wrong
> anyway.
> 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. The boot source is out of scope for the
> watchdog
> status bits.
>
> Thanks,
> Guenter
>
Ast2600 has external reset flag on scu74 bit 1
Can I modify the code like this?
To set WDIOF_EXTERN1 if EXTERN_RESET_FLAG is set,
To set WDIOF_CARDRESET if WDT_TIMEOUT_STATUS_EVENT(bit0) is set
#define WDT_TIMEOUT_STATUS_EVENT BIT(0)
#define EXTERN_RESET_FLAG BIT(1)
#define ASPEED_SYSTEM_RESET_EVENT (0x74)
status = readl(wdt->base + WDT_TIMEOUT_STATUS);
if (status & WDT_TIMEOUT_STATUS_EVENT)
wdt->wdd.bootstatus = WDIOF_CARDRESET;
if (of_device_is_compatible(np, "aspeed,ast2600-wdt")) {
status = readl(wdt->scu_base + ASPEED_SYSTEM_RESET_EVENT);
if (status & EXTERN_RESET_FLAG)
/*
* Reset cause by Extern Reset
*/
wdt->wdd.bootstatus |= WDIOF_EXTERN1;
} else {
wdt->wdd.groups = bswitch_groups;
}
Thanks,
Peter.
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