Re: [U-Boot] [U-Boot,RFC,v1] wdt: Add a glue driver for watchdog

On 07/05/2017 07:45 PM, Andy Shevchenko wrote:

This driver enables first found watchdog as a system one and uses it as a system hardware watchdog device by providing hw_watchdog_reset(), hw_watchdog_disable() and void hw_watchdog_init() hooks.

Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com

This is not a working solution, just an opinion to which direction we might go with ugly broken WDT class.

We need a watchdog driver to complete the UEFI implementation.

Currently you are only thinking about a hardware watchdog. We do not have hardware watchdog drivers for every board.

I would prefer if we had a software fallback solution that would update the timer ticks when waiting for keyboard or in other loops like network traffic.

Best regards

Heinrich

Feel free to ignore, drop, modify, etc.

drivers/watchdog/Kconfig | 8 +++++++ drivers/watchdog/Makefile | 1 + drivers/watchdog/wdt-hw.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 64 insertions(+) create mode 100644 drivers/watchdog/wdt-hw.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 0ed5aa987f..4837e73565 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -35,6 +35,14 @@ config WDT What exactly happens when the timer expires is up to a particular device/driver.

+config WDT_HW

• bool "Enable hardware Watchdog Timer"
• depends on WDT
• select HW_WATCHDOG
• help

• Enable hardware Watchdog Timer. This is a glue driver to enable
  

• first found watchdog device as a system one.
  

config WDT_SANDBOX bool "Enable Watchdog Timer support for Sandbox" depends on SANDBOX && WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 0ad16f661e..c4a297e88b 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_OMAP_WATCHDOG) += omap_wdt.o obj-$(CONFIG_DESIGNWARE_WATCHDOG) += designware_wdt.o obj-$(CONFIG_ULP_WATCHDOG) += ulp_wdog.o obj-$(CONFIG_WDT) += wdt-uclass.o +obj-$(CONFIG_WDT_HW) += wdt-hw.o obj-$(CONFIG_WDT_SANDBOX) += sandbox_wdt.o obj-$(CONFIG_WDT_ASPEED) += ast_wdt.o obj-$(CONFIG_WDT_BCM6345) += bcm6345_wdt.o diff --git a/drivers/watchdog/wdt-hw.c b/drivers/watchdog/wdt-hw.c new file mode 100644 index 0000000000..3e98db86c8 --- /dev/null +++ b/drivers/watchdog/wdt-hw.c @@ -0,0 +1,55 @@ +/*

• • Copyright (c) 2017 Intel Corporation
• • SPDX-License-Identifier: GPL-2.0+
• */

+#include <common.h> +#include <dm.h> +#include <wdt.h>

+/* Hardware timeout in milliseconds */ +#ifdef CONFIG_WATCHDOG_TIMEOUT_MSECS +#define WATCHDOG_HEARTBEAT CONFIG_WATCHDOG_TIMEOUT_MSECS +#else +#define WATCHDOG_HEARTBEAT 60000 +#endif

+static struct udevice *wdt;

+void hw_watchdog_reset(void) +{

• int ret;
• if (!wdt)

• return;
  

• ret = wdt_reset(wdt);
• if (ret)

• printf("Can't reset watchdog device: %d\n", ret);
  

+}

+void hw_watchdog_disable(void) +{

• int ret;
• if (!wdt)

• return;
  

• ret = wdt_stop(wdt);
• if (ret)

• printf("Can't stop watchdog device: %d\n", ret);
  

+}

+void hw_watchdog_init(void) +{

• int ret;
• ret = uclass_first_device(UCLASS_WDT, &wdt);
• if (ret)

• printf("Can't find watchdog device: %d\n", ret);
  

• else {

• ret = wdt_start(wdt, WATCHDOG_HEARTBEAT * 1000, 0);
  

• if (ret)
  

• 	printf("Can't start watchdog device: %d\n", ret);
  

• }

+}