[PATCH v5 2/2] drivers/watchdog: ASPEED reference dev tree properties for config
From: Christopher Bostic <hidden>
Date: 2017-07-17 19:26:12
Also in:
linux-watchdog, lkml, openbmc
Subsystem:
the rest, watchdog device drivers · Maintainers:
Linus Torvalds, Wim Van Sebroeck, Guenter Roeck
Reference the system device tree when configuring the watchdog
engines. If property 'aspeed,reset_type' is present then set
reset behavior based on the specified value. This can be one of
three different mutually exclusive values
* cpu - Reset CPU only on watchdog timeout
* soc - Reset System on Chip
* system - Full system reset
No reset can also be specified by indicating:
* none - No reset, assumes another watchdog is responsible for
this.
Add optional property 'aspeed,external-signal'. If present then
configure to generate external signal on watchdog timeout.
Signed-off-by: Christopher Bostic <redacted>
---
v5 - Add explicit check for property type "none". Return error
if property type is not a known value.
- Default reset type when no property present changed to
match original code: SOC + SYSTEM reset
v4 - Change the three reset type parameters to a new property
'aspeed,reset_type' and check assignment for one of four
different values, cpu, soc, system, none
v3 - Invert the logic for system reset dev tree property to
preserve backwards compatibility. If not specified the
default is to configure for system reset
- Add check for 'aspeed,no-soc-reset' property and only if
not present is SOC reset to be configured. This preserves
backwards compatibility.
v2 - Change of_get_property() to of_property_read_bool()
- Remove redundant check for NULL struct device_node pointer
- Optional property names now start with prefix 'aspeed,'
---
drivers/watchdog/aspeed_wdt.c | 29 ++++++++++++++++++++++++-----
1 file changed, 24 insertions(+), 5 deletions(-)
diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index 1c65258..c707ab6 100644
--- a/drivers/watchdog/aspeed_wdt.c
+++ b/drivers/watchdog/aspeed_wdt.c@@ -36,6 +36,7 @@ struct aspeed_wdt { #define WDT_CTRL 0x0C #define WDT_CTRL_RESET_MODE_SOC (0x00 << 5) #define WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5) +#define WDT_CTRL_RESET_MODE_ARM_CPU (0x10 << 5) #define WDT_CTRL_1MHZ_CLK BIT(4) #define WDT_CTRL_WDT_EXT BIT(3) #define WDT_CTRL_WDT_INTR BIT(2)
@@ -140,6 +141,8 @@ static int aspeed_wdt_probe(struct platform_device *pdev) { struct aspeed_wdt *wdt; struct resource *res; + struct device_node *np; + const char *reset_type; int ret; wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
@@ -164,14 +167,30 @@ static int aspeed_wdt_probe(struct platform_device *pdev) wdt->wdd.timeout = WDT_DEFAULT_TIMEOUT; watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev); + wdt->ctrl = WDT_CTRL_1MHZ_CLK; + /* * Control reset on a per-device basis to ensure the - * host is not affected by a BMC reboot, so only reset - * the SOC and not the full chip + * host is not affected by a BMC reboot */ - wdt->ctrl = WDT_CTRL_RESET_MODE_SOC | - WDT_CTRL_1MHZ_CLK | - WDT_CTRL_RESET_SYSTEM; + np = pdev->dev.of_node; + ret = of_property_read_string(np, "aspeed,reset-type", &reset_type); + if (ret) { + wdt->ctrl |= WDT_CTRL_RESET_MODE_SOC | WDT_CTRL_RESET_SYSTEM; + } else { + if (!strcmp(reset_type, "cpu")) + wdt->ctrl |= WDT_CTRL_RESET_MODE_ARM_CPU; + else if (!strcmp(reset_type, "soc")) + wdt->ctrl |= WDT_CTRL_RESET_MODE_SOC; + else if (!strcmp(reset_type, "system")) + wdt->ctrl |= WDT_CTRL_RESET_SYSTEM; + else if (strcmp(reset_type, "none")) + return -EINVAL; + } + if (of_property_read_bool(np, "aspeed,external-signal")) + wdt->ctrl |= WDT_CTRL_WDT_EXT; + + writel(wdt->ctrl, wdt->base + WDT_CTRL); if (readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE) { aspeed_wdt_start(&wdt->wdd);
--
1.8.2.2