This watchdog driver applies to the following mcf families:
- mcf52x2 (5271 5275 5282) - mcf532x (5329 5373) - mcf523x (5235)
Cpu's not listed for each family does not have WDT module.
Note, after some attempts testing by qemu on 5208 i finally abandoned, watchdog seems not implemented properly.
The driver has been tested in a real M5282EVM.
Signed-off-by: Angelo Dureghello angelo@kernel-space.org --- Changes for v2: - remove unnecessary hardcoded timeouts - remove unnecessary hw_watchdog_xxx stuff - rewrite wdog module reg calculation - using IS_ENABLED() where possible --- drivers/watchdog/Kconfig | 7 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/mcf_wdt.c | 137 +++++++++++++++++++++++++++++++++++++ 3 files changed, 145 insertions(+) create mode 100644 drivers/watchdog/mcf_wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 646663528a..07fc4940e9 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -178,6 +178,13 @@ config WDT_MAX6370 help Select this to enable max6370 watchdog timer.
+config WDT_MCF + bool "ColdFire family watchdog timer support" + depends on WDT + help + Select this to enable ColdFire watchdog timer, + which supports mcf52x2 mcf532x mcf523x families. + config WDT_MESON_GXBB bool "Amlogic watchdog timer support" depends on WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index fd5d9c7376..eef786f5e7 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -31,6 +31,7 @@ obj-$(CONFIG_WDT_CDNS) += cdns_wdt.o obj-$(CONFIG_WDT_FTWDT010) += ftwdt010_wdt.o obj-$(CONFIG_WDT_GPIO) += gpio_wdt.o obj-$(CONFIG_WDT_MAX6370) += max6370_wdt.o +obj-$(CONFIG_WDT_MCF) += mcf_wdt.o obj-$(CONFIG_WDT_MESON_GXBB) += meson_gxbb_wdt.o obj-$(CONFIG_WDT_MPC8xxx) += mpc8xxx_wdt.o obj-$(CONFIG_WDT_MT7620) += mt7620_wdt.o diff --git a/drivers/watchdog/mcf_wdt.c b/drivers/watchdog/mcf_wdt.c new file mode 100644 index 0000000000..cad6097a7d --- /dev/null +++ b/drivers/watchdog/mcf_wdt.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * mcf_wdt.c - driver for ColdFire on-chip watchdog + * + * Author: Angelo Dureghello angelo@kernel-space.org + * + */ + +#include <common.h> +#include <dm.h> +#include <hang.h> +#include <asm/io.h> +#include <wdt.h> +#include <linux/bitops.h> + +#define DIVIDER_5XXX 4096 +#define DIVIDER_5282 8192 + +#define WCR_EN BIT(0) +#define WCR_HALTED BIT(1) +#define WCR_DOZE BIT(2) +#define WCR_WAIT BIT(3) + +struct watchdog_regs { + u16 wcr; /* Control */ + u16 wmr; /* Service */ + u16 wcntr; /* Counter */ + u16 wsr; /* Reset Status */ +}; + +static void mcf_watchdog_reset(struct watchdog_regs *wdog) +{ + if (!IS_ENABLED(CONFIG_WATCHDOG_RESET_DISABLE)) { + writew(0x5555, &wdog->wsr); + writew(0xaaaa, &wdog->wsr); + } +} + +static void mcf_watchdog_init(struct watchdog_regs *wdog, u32 fixed_divider, + u64 timeout_msecs) +{ + u32 wdog_module, cycles_per_sec; + + cycles_per_sec = CFG_SYS_CLK / fixed_divider; + + wdog_module = cycles_per_sec * ((u32)timeout_msecs / 1000); + wdog_module += (cycles_per_sec / 1000) * ((u32)timeout_msecs % 1000); + + /* Limit check, max 16 bits */ + if (wdog_module > 0xffff) + wdog_module = 0xffff; + + wdog_module = 0x8000; + + /* Set timeout and enable watchdog */ + writew((u16)wdog_module, &wdog->wmr); + writew(WCR_EN, &wdog->wcr); + + mcf_watchdog_reset(wdog); +} + +struct mcf_wdt_priv { + void __iomem *base; + u32 fixed_divider; +}; + +static int mcf_wdt_expire_now(struct udevice *dev, ulong flags) +{ + hang(); + + return 0; +} + +static int mcf_wdt_reset(struct udevice *dev) +{ + struct mcf_wdt_priv *priv = dev_get_priv(dev); + + mcf_watchdog_reset(priv->base); + + return 0; +} + +static int mcf_wdt_start(struct udevice *dev, u64 timeout, ulong flags) +{ + struct mcf_wdt_priv *priv = dev_get_priv(dev); + + /* Timeout from fdt (timeout) comes in milliseconds */ + mcf_watchdog_init(priv->base, priv->fixed_divider, timeout); + + return 0; +} + +static int mcf_wdt_stop(struct udevice *dev) +{ + struct mcf_wdt_priv *priv = dev_get_priv(dev); + struct watchdog_regs *wdog = (struct watchdog_regs *)priv->base; + + setbits_be16(&wdog->wcr, WCR_HALTED); + + return 0; +} + +static int mcf_wdt_probe(struct udevice *dev) +{ + struct mcf_wdt_priv *priv = dev_get_priv(dev); + + priv->base = dev_read_addr_ptr(dev); + if (!priv->base) + return -ENOENT; + + priv->fixed_divider = (u32)dev_get_driver_data(dev); + + return 0; +} + +static const struct wdt_ops mcf_wdt_ops = { + .start = mcf_wdt_start, + .stop = mcf_wdt_stop, + .reset = mcf_wdt_reset, + .expire_now = mcf_wdt_expire_now, +}; + +static const struct udevice_id mcf_wdt_ids[] = { + { .compatible = "fsl,mcf5208-wdt", .data = DIVIDER_5XXX }, + { .compatible = "fsl,mcf5282-wdt", .data = DIVIDER_5282 }, + {} +}; + +U_BOOT_DRIVER(mcf_wdt) = { + .name = "mcf_wdt", + .id = UCLASS_WDT, + .of_match = mcf_wdt_ids, + .probe = mcf_wdt_probe, + .ops = &mcf_wdt_ops, + .priv_auto = sizeof(struct mcf_wdt_priv), + .flags = DM_FLAG_PRE_RELOC, +};