diff options
Diffstat (limited to 'roms/u-boot/drivers/watchdog/imx_watchdog.c')
-rw-r--r-- | roms/u-boot/drivers/watchdog/imx_watchdog.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/watchdog/imx_watchdog.c b/roms/u-boot/drivers/watchdog/imx_watchdog.c new file mode 100644 index 000000000..3586246fb --- /dev/null +++ b/roms/u-boot/drivers/watchdog/imx_watchdog.c @@ -0,0 +1,176 @@ +/* + * watchdog.c - driver for i.mx on-chip watchdog + * + * Licensed under the GPL-2 or later. + */ + +#include <common.h> +#include <cpu_func.h> +#include <dm.h> +#include <hang.h> +#include <asm/io.h> +#include <wdt.h> +#include <watchdog.h> +#include <asm/arch/imx-regs.h> +#ifdef CONFIG_FSL_LSCH2 +#include <asm/arch/immap_lsch2.h> +#endif +#include <fsl_wdog.h> +#include <div64.h> + +#define TIMEOUT_MAX 128000 +#define TIMEOUT_MIN 500 + +static void imx_watchdog_expire_now(struct watchdog_regs *wdog, bool ext_reset) +{ + u16 wcr = WCR_WDE; + + if (ext_reset) + wcr |= WCR_SRS; /* do not assert internal reset */ + else + wcr |= WCR_WDA; /* do not assert external reset */ + + /* Write 3 times to ensure it works, due to IMX6Q errata ERR004346 */ + writew(wcr, &wdog->wcr); + writew(wcr, &wdog->wcr); + writew(wcr, &wdog->wcr); + + while (1) { + /* + * spin before reset + */ + } +} + +#if !defined(CONFIG_IMX_WATCHDOG) || \ + (defined(CONFIG_IMX_WATCHDOG) && !CONFIG_IS_ENABLED(WDT)) +void __attribute__((weak)) reset_cpu(void) +{ + struct watchdog_regs *wdog = (struct watchdog_regs *)WDOG1_BASE_ADDR; + + imx_watchdog_expire_now(wdog, true); +} +#endif + +#if defined(CONFIG_IMX_WATCHDOG) +static void imx_watchdog_reset(struct watchdog_regs *wdog) +{ +#ifndef CONFIG_WATCHDOG_RESET_DISABLE + writew(0x5555, &wdog->wsr); + writew(0xaaaa, &wdog->wsr); +#endif /* CONFIG_WATCHDOG_RESET_DISABLE*/ +} + +static void imx_watchdog_init(struct watchdog_regs *wdog, bool ext_reset, + u64 timeout) +{ + u16 wcr; + + /* + * The timer watchdog can be set between + * 0.5 and 128 Seconds. If not defined + * in configuration file, sets 128 Seconds + */ +#ifndef CONFIG_WATCHDOG_TIMEOUT_MSECS +#define CONFIG_WATCHDOG_TIMEOUT_MSECS 128000 +#endif + + timeout = max_t(u64, timeout, TIMEOUT_MIN); + timeout = min_t(u64, timeout, TIMEOUT_MAX); + timeout = lldiv(timeout, 500) - 1; + +#ifdef CONFIG_FSL_LSCH2 + wcr = (WCR_WDA | WCR_SRS | WCR_WDE) << 8 | timeout; +#else + wcr = WCR_WDZST | WCR_WDBG | WCR_WDE | WCR_SRS | + WCR_WDA | SET_WCR_WT(timeout); + if (ext_reset) + wcr |= WCR_WDT; +#endif /* CONFIG_FSL_LSCH2*/ + writew(wcr, &wdog->wcr); + imx_watchdog_reset(wdog); +} + +#if !CONFIG_IS_ENABLED(WDT) +void hw_watchdog_reset(void) +{ + struct watchdog_regs *wdog = (struct watchdog_regs *)WDOG1_BASE_ADDR; + + imx_watchdog_reset(wdog); +} + +void hw_watchdog_init(void) +{ + struct watchdog_regs *wdog = (struct watchdog_regs *)WDOG1_BASE_ADDR; + + imx_watchdog_init(wdog, true, CONFIG_WATCHDOG_TIMEOUT_MSECS); +} +#else +struct imx_wdt_priv { + void __iomem *base; + bool ext_reset; +}; + +static int imx_wdt_reset(struct udevice *dev) +{ + struct imx_wdt_priv *priv = dev_get_priv(dev); + + imx_watchdog_reset(priv->base); + + return 0; +} + +static int imx_wdt_expire_now(struct udevice *dev, ulong flags) +{ + struct imx_wdt_priv *priv = dev_get_priv(dev); + + imx_watchdog_expire_now(priv->base, priv->ext_reset); + hang(); + + return 0; +} + +static int imx_wdt_start(struct udevice *dev, u64 timeout, ulong flags) +{ + struct imx_wdt_priv *priv = dev_get_priv(dev); + + imx_watchdog_init(priv->base, priv->ext_reset, timeout); + + return 0; +} + +static int imx_wdt_probe(struct udevice *dev) +{ + struct imx_wdt_priv *priv = dev_get_priv(dev); + + priv->base = dev_read_addr_ptr(dev); + if (!priv->base) + return -ENOENT; + + priv->ext_reset = dev_read_bool(dev, "fsl,ext-reset-output"); + + return 0; +} + +static const struct wdt_ops imx_wdt_ops = { + .start = imx_wdt_start, + .reset = imx_wdt_reset, + .expire_now = imx_wdt_expire_now, +}; + +static const struct udevice_id imx_wdt_ids[] = { + { .compatible = "fsl,imx21-wdt" }, + {} +}; + +U_BOOT_DRIVER(imx_wdt) = { + .name = "imx_wdt", + .id = UCLASS_WDT, + .of_match = imx_wdt_ids, + .probe = imx_wdt_probe, + .ops = &imx_wdt_ops, + .priv_auto = sizeof(struct imx_wdt_priv), + .flags = DM_FLAG_PRE_RELOC, +}; +#endif +#endif |