Add SIGALRM based watchdog driver. This can reset barebox if stuck and plays nicely with $global.system.reset.
Signed-off-by: Ahmad Fatoum <[email protected]> --- v1 -> v2: no changes --- arch/sandbox/board/Makefile | 1 + arch/sandbox/board/watchdog.c | 84 +++++++++++++++++++ arch/sandbox/dts/sandbox.dts | 5 ++ .../sandbox/mach-sandbox/include/mach/linux.h | 2 + arch/sandbox/os/common.c | 25 ++++++ 5 files changed, 117 insertions(+) create mode 100644 arch/sandbox/board/watchdog.c diff --git a/arch/sandbox/board/Makefile b/arch/sandbox/board/Makefile index e50d2ca0f148..c504c967decd 100644 --- a/arch/sandbox/board/Makefile +++ b/arch/sandbox/board/Makefile @@ -6,5 +6,6 @@ obj-y += devices.o obj-y += dtb.o obj-y += power.o obj-y += dev-random.o +obj-y += watchdog.o extra-y += barebox.lds diff --git a/arch/sandbox/board/watchdog.c b/arch/sandbox/board/watchdog.c new file mode 100644 index 000000000000..336451282fd3 --- /dev/null +++ b/arch/sandbox/board/watchdog.c @@ -0,0 +1,84 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <common.h> +#include <errno.h> +#include <driver.h> +#include <mach/linux.h> +#include <of.h> +#include <watchdog.h> +#include <mfd/syscon.h> +#include <reset_source.h> + +struct sandbox_watchdog { + struct watchdog wdd; + bool cant_disable :1; +}; + +static inline struct sandbox_watchdog *to_sandbox_watchdog(struct watchdog *wdd) +{ + return container_of(wdd, struct sandbox_watchdog, wdd); +} + +static int sandbox_watchdog_set_timeout(struct watchdog *wdd, unsigned int timeout) +{ + struct sandbox_watchdog *wd = to_sandbox_watchdog(wdd); + + if (!timeout && wd->cant_disable) + return -ENOSYS; + + if (timeout > wdd->timeout_max) + return -EINVAL; + + return linux_watchdog_set_timeout(timeout); +} + +static int sandbox_watchdog_probe(struct device_d *dev) +{ + struct device_node *np = dev->device_node; + struct sandbox_watchdog *wd; + struct watchdog *wdd; + struct regmap *src; + u32 src_offset; + int ret; + + wd = xzalloc(sizeof(*wd)); + + wdd = &wd->wdd; + wdd->hwdev = dev; + wdd->set_timeout = sandbox_watchdog_set_timeout; + wdd->timeout_max = 1000; + + wd->cant_disable = of_property_read_bool(np, "barebox,cant-disable"); + + ret = watchdog_register(wdd); + if (ret) { + dev_err(dev, "Failed to register watchdog device\n"); + return ret; + } + + src = syscon_regmap_lookup_by_phandle(np, "barebox,reset-source"); + if (IS_ERR(src)) + return 0; + + ret = of_property_read_u32_index(np, "barebox,reset-source", 1, &src_offset); + if (ret) + return 0; + + regmap_update_bits(src, src_offset, 0xff, RESET_WDG); + + dev_info(dev, "probed\n"); + return 0; +} + + +static __maybe_unused struct of_device_id sandbox_watchdog_dt_ids[] = { + { .compatible = "barebox,sandbox-watchdog" }, + { /* sentinel */ } +}; + +static struct driver_d sandbox_watchdog_drv = { + .name = "sandbox-watchdog", + .of_compatible = sandbox_watchdog_dt_ids, + .probe = sandbox_watchdog_probe, +}; +device_platform_driver(sandbox_watchdog_drv); diff --git a/arch/sandbox/dts/sandbox.dts b/arch/sandbox/dts/sandbox.dts index be96745b4274..f830adecf796 100644 --- a/arch/sandbox/dts/sandbox.dts +++ b/arch/sandbox/dts/sandbox.dts @@ -54,4 +54,9 @@ compatible = "barebox,sandbox-power"; barebox,reset-source = <&stickypage 0>; }; + + watchdog { + compatible = "barebox,sandbox-watchdog"; + barebox,reset-source = <&stickypage 0>; + }; }; diff --git a/arch/sandbox/mach-sandbox/include/mach/linux.h b/arch/sandbox/mach-sandbox/include/mach/linux.h index 7bb022a6de1d..b26bfc24a291 100644 --- a/arch/sandbox/mach-sandbox/include/mach/linux.h +++ b/arch/sandbox/mach-sandbox/include/mach/linux.h @@ -25,6 +25,8 @@ void linux_reexec(void); int linux_execve(const char * filename, char *const argv[], char *const envp[]); +int linux_watchdog_set_timeout(unsigned int timeout); + int barebox_register_console(int stdinfd, int stdoutfd); int barebox_register_dtb(const void *dtb); diff --git a/arch/sandbox/os/common.c b/arch/sandbox/os/common.c index 54d2b97b4af7..da87be29c74d 100644 --- a/arch/sandbox/os/common.c +++ b/arch/sandbox/os/common.c @@ -39,6 +39,8 @@ #include <sys/wait.h> #include <sys/ioctl.h> #include <linux/fs.h> +#include <sys/time.h> +#include <signal.h> /* * ...except the ones needed to connect with barebox */ @@ -244,6 +246,29 @@ int linux_execve(const char * filename, char *const argv[], char *const envp[]) } } +static void linux_watchdog(int signo) +{ + linux_reexec(); + _exit(0); +} + +int linux_watchdog_set_timeout(unsigned int timeout) +{ + static int signal_handler_installed; + + if (!signal_handler_installed) { + struct sigaction sact = { + .sa_flags = SA_NODEFER, .sa_handler = linux_watchdog + }; + + sigemptyset(&sact.sa_mask); + sigaction(SIGALRM, &sact, NULL); + signal_handler_installed = 1; + } + + return alarm(timeout); +} + extern void start_barebox(void); extern void mem_malloc_init(void *start, void *end); -- 2.28.0 _______________________________________________ barebox mailing list [email protected] http://lists.infradead.org/mailman/listinfo/barebox
