From da264550980aee9d5ed4e6c18d4a4b027c2e242b Mon Sep 17 00:00:00 2001 From: Chanho Park Date: Mon, 6 Nov 2023 08:13:16 +0900 Subject: [PATCH] watchdog: Add StarFive Watchdog driver Add to support StarFive watchdog driver. The driver is imported from linux kernel's drivers/watchdog/starfive-wdt.c without jh7100 support because there is no support of jh7100 SoC in u-boot yet. Howver, this patch has been kept the variant coding style because JH7100 can be added later and have a consistency with the linux driver. Signed-off-by: Chanho Park Reviewed-by: Leo Yu-Chi Liang --- drivers/watchdog/Kconfig | 7 + drivers/watchdog/Makefile | 1 + drivers/watchdog/starfive_wdt.c | 329 ++++++++++++++++++++++++++++++++ 3 files changed, 337 insertions(+) create mode 100644 drivers/watchdog/starfive_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 07fc4940e9..569726119c 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -344,6 +344,13 @@ config WDT_STM32MP Enable the STM32 watchdog (IWDG) driver. Enable support to configure STM32's on-SoC watchdog. +config WDT_STARFIVE + bool "StarFive watchdog timer support" + depends on WDT + imply WATCHDOG + help + Enable support for the watchdog timer of StarFive JH7110 SoC. + config WDT_SUNXI bool "Allwinner sunxi watchdog timer support" depends on WDT && ARCH_SUNXI diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index eef786f5e7..5520d3d9ae 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_WDT_SBSA) += sbsa_gwdt.o obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o obj-$(CONFIG_WDT_SL28CPLD) += sl28cpld-wdt.o obj-$(CONFIG_WDT_SP805) += sp805_wdt.o +obj-$(CONFIG_WDT_STARFIVE) += starfive_wdt.o obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o obj-$(CONFIG_WDT_SUNXI) += sunxi_wdt.o obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o diff --git a/drivers/watchdog/starfive_wdt.c b/drivers/watchdog/starfive_wdt.c new file mode 100644 index 0000000000..ee9ec4cdc3 --- /dev/null +++ b/drivers/watchdog/starfive_wdt.c @@ -0,0 +1,329 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Starfive Watchdog driver + * + * Copyright (C) 2022 StarFive Technology Co., Ltd. + */ + +#include +#include +#include +#include +#include + +/* JH7110 Watchdog register define */ +#define STARFIVE_WDT_JH7110_LOAD 0x000 +#define STARFIVE_WDT_JH7110_VALUE 0x004 +#define STARFIVE_WDT_JH7110_CONTROL 0x008 /* + * [0]: reset enable; + * [1]: interrupt enable && watchdog enable + * [31:2]: reserved. + */ +#define STARFIVE_WDT_JH7110_INTCLR 0x00c /* clear intterupt and reload the counter */ +#define STARFIVE_WDT_JH7110_IMS 0x014 +#define STARFIVE_WDT_JH7110_LOCK 0xc00 /* write 0x1ACCE551 to unlock */ + +/* WDOGCONTROL */ +#define STARFIVE_WDT_ENABLE 0x1 +#define STARFIVE_WDT_EN_SHIFT 0 +#define STARFIVE_WDT_RESET_EN 0x1 +#define STARFIVE_WDT_JH7110_RST_EN_SHIFT 1 + +/* WDOGLOCK */ +#define STARFIVE_WDT_JH7110_UNLOCK_KEY 0x1acce551 + +/* WDOGINTCLR */ +#define STARFIVE_WDT_INTCLR 0x1 +#define STARFIVE_WDT_JH7100_INTCLR_AVA_SHIFT 1 /* Watchdog can clear interrupt when 0 */ + +#define STARFIVE_WDT_MAXCNT 0xffffffff +#define STARFIVE_WDT_DEFAULT_TIME (15) +#define STARFIVE_WDT_DELAY_US 0 +#define STARFIVE_WDT_TIMEOUT_US 10000 + +/* module parameter */ +#define STARFIVE_WDT_EARLY_ENA 0 + +struct starfive_wdt_variant { + unsigned int control; /* Watchdog Control Resgister for reset enable */ + unsigned int load; /* Watchdog Load register */ + unsigned int reload; /* Watchdog Reload Control register */ + unsigned int enable; /* Watchdog Enable Register */ + unsigned int value; /* Watchdog Counter Value Register */ + unsigned int int_clr; /* Watchdog Interrupt Clear Register */ + unsigned int unlock; /* Watchdog Lock Register */ + unsigned int int_status; /* Watchdog Interrupt Status Register */ + + u32 unlock_key; + char enrst_shift; + char en_shift; + bool intclr_check; /* whether need to check it before clearing interrupt */ + char intclr_ava_shift; + bool double_timeout; /* The watchdog need twice timeout to reboot */ +}; + +struct starfive_wdt_priv { + void __iomem *base; + struct clk *core_clk; + struct clk *apb_clk; + struct reset_ctl_bulk *rst; + const struct starfive_wdt_variant *variant; + unsigned long freq; + u32 count; /* count of timeout */ + u32 reload; /* restore the count */ +}; + +/* Register layout and configuration for the JH7110 */ +static const struct starfive_wdt_variant starfive_wdt_jh7110_variant = { + .control = STARFIVE_WDT_JH7110_CONTROL, + .load = STARFIVE_WDT_JH7110_LOAD, + .enable = STARFIVE_WDT_JH7110_CONTROL, + .value = STARFIVE_WDT_JH7110_VALUE, + .int_clr = STARFIVE_WDT_JH7110_INTCLR, + .unlock = STARFIVE_WDT_JH7110_LOCK, + .unlock_key = STARFIVE_WDT_JH7110_UNLOCK_KEY, + .int_status = STARFIVE_WDT_JH7110_IMS, + .enrst_shift = STARFIVE_WDT_JH7110_RST_EN_SHIFT, + .en_shift = STARFIVE_WDT_EN_SHIFT, + .intclr_check = false, + .double_timeout = true, +}; + +static int starfive_wdt_enable_clock(struct starfive_wdt_priv *wdt) +{ + int ret; + + ret = clk_enable(wdt->apb_clk); + if (ret) + return ret; + + ret = clk_enable(wdt->core_clk); + if (ret) { + clk_disable(wdt->apb_clk); + return ret; + } + + return 0; +} + +static void starfive_wdt_disable_clock(struct starfive_wdt_priv *wdt) +{ + clk_disable(wdt->core_clk); + clk_disable(wdt->apb_clk); +} + +/* Write unlock-key to unlock. Write other value to lock. */ +static void starfive_wdt_unlock(struct starfive_wdt_priv *wdt) +{ + writel(wdt->variant->unlock_key, wdt->base + wdt->variant->unlock); +} + +static void starfive_wdt_lock(struct starfive_wdt_priv *wdt) +{ + writel(~wdt->variant->unlock_key, wdt->base + wdt->variant->unlock); +} + +/* enable watchdog interrupt to reset/reboot */ +static void starfive_wdt_enable_reset(struct starfive_wdt_priv *wdt) +{ + u32 val; + + val = readl(wdt->base + wdt->variant->control); + val |= STARFIVE_WDT_RESET_EN << wdt->variant->enrst_shift; + writel(val, wdt->base + wdt->variant->control); +} + +/* waiting interrupt can be free to clear */ +static int starfive_wdt_wait_int_free(struct starfive_wdt_priv *wdt) +{ + u32 value; + + return readl_poll_timeout(wdt->base + wdt->variant->int_clr, value, + !(value & BIT(wdt->variant->intclr_ava_shift)), + STARFIVE_WDT_TIMEOUT_US); +} + +/* clear interrupt signal before initialization or reload */ +static int starfive_wdt_int_clr(struct starfive_wdt_priv *wdt) +{ + int ret; + + if (wdt->variant->intclr_check) { + ret = starfive_wdt_wait_int_free(wdt); + if (ret) + return ret; + } + writel(STARFIVE_WDT_INTCLR, wdt->base + wdt->variant->int_clr); + + return 0; +} + +static inline void starfive_wdt_set_count(struct starfive_wdt_priv *wdt, + u32 val) +{ + writel(val, wdt->base + wdt->variant->load); +} + +/* enable watchdog */ +static inline void starfive_wdt_enable(struct starfive_wdt_priv *wdt) +{ + u32 val; + + val = readl(wdt->base + wdt->variant->enable); + val |= STARFIVE_WDT_ENABLE << wdt->variant->en_shift; + writel(val, wdt->base + wdt->variant->enable); +} + +/* disable watchdog */ +static inline void starfive_wdt_disable(struct starfive_wdt_priv *wdt) +{ + u32 val; + + val = readl(wdt->base + wdt->variant->enable); + val &= ~(STARFIVE_WDT_ENABLE << wdt->variant->en_shift); + writel(val, wdt->base + wdt->variant->enable); +} + +static inline void starfive_wdt_set_reload_count(struct starfive_wdt_priv *wdt, + u32 count) +{ + starfive_wdt_set_count(wdt, count); + + /* 7100 need set any value to reload register and could reload value to counter */ + if (wdt->variant->reload) + writel(0x1, wdt->base + wdt->variant->reload); +} + +static int starfive_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags) +{ + int ret; + struct starfive_wdt_priv *wdt = dev_get_priv(dev); + + starfive_wdt_unlock(wdt); + /* disable watchdog, to be safe */ + starfive_wdt_disable(wdt); + + starfive_wdt_enable_reset(wdt); + ret = starfive_wdt_int_clr(wdt); + if (ret) + goto exit; + + wdt->count = (timeout_ms / 1000) * wdt->freq; + if (wdt->variant->double_timeout) + wdt->count /= 2; + + starfive_wdt_set_count(wdt, wdt->count); + starfive_wdt_enable(wdt); + +exit: + starfive_wdt_lock(wdt); + return ret; +} + +static int starfive_wdt_stop(struct udevice *dev) +{ + struct starfive_wdt_priv *wdt = dev_get_priv(dev); + + starfive_wdt_unlock(wdt); + starfive_wdt_disable(wdt); + starfive_wdt_lock(wdt); + + return 0; +} + +static int starfive_wdt_reset(struct udevice *dev) +{ + int ret; + struct starfive_wdt_priv *wdt = dev_get_priv(dev); + + starfive_wdt_unlock(wdt); + ret = starfive_wdt_int_clr(wdt); + if (ret) + goto exit; + + starfive_wdt_set_reload_count(wdt, wdt->count); + +exit: + starfive_wdt_lock(wdt); + + return ret; +} + +static const struct wdt_ops starfive_wdt_ops = { + .start = starfive_wdt_start, + .stop = starfive_wdt_stop, + .reset = starfive_wdt_reset, +}; + +static int starfive_wdt_probe(struct udevice *dev) +{ + struct starfive_wdt_priv *wdt = dev_get_priv(dev); + int ret; + + ret = starfive_wdt_enable_clock(wdt); + if (ret) + return ret; + + ret = reset_deassert_bulk(wdt->rst); + if (ret) + goto err_reset; + + wdt->variant = (const struct starfive_wdt_variant *)dev_get_driver_data(dev); + + wdt->freq = clk_get_rate(wdt->core_clk); + if (!wdt->freq) { + ret = -EINVAL; + goto err_get_freq; + } + + return 0; + +err_get_freq: + reset_assert_bulk(wdt->rst); +err_reset: + starfive_wdt_disable_clock(wdt); + + return ret; +} + +static int starfive_wdt_of_to_plat(struct udevice *dev) +{ + struct starfive_wdt_priv *wdt = dev_get_priv(dev); + + wdt->base = (void *)dev_read_addr(dev); + if (!wdt->base) + return -ENODEV; + + wdt->apb_clk = devm_clk_get(dev, "apb"); + if (IS_ERR(wdt->apb_clk)) + return -ENODEV; + + wdt->core_clk = devm_clk_get(dev, "core"); + if (IS_ERR(wdt->core_clk)) + return -ENODEV; + + wdt->rst = devm_reset_bulk_get(dev); + if (IS_ERR(wdt->rst)) + return -ENODEV; + + return 0; +} + +static const struct udevice_id starfive_wdt_ids[] = { + { + .compatible = "starfive,jh7110-wdt", + .data = (ulong)&starfive_wdt_jh7110_variant + }, { + /* sentinel */ + } +}; + +U_BOOT_DRIVER(starfive_wdt) = { + .name = "starfive_wdt", + .id = UCLASS_WDT, + .of_match = starfive_wdt_ids, + .priv_auto = sizeof(struct starfive_wdt_priv), + .probe = starfive_wdt_probe, + .of_to_plat = starfive_wdt_of_to_plat, + .ops = &starfive_wdt_ops, +};