diff options
Diffstat (limited to 'drivers/watchdog/zx2967_wdt.c')
-rw-r--r-- | drivers/watchdog/zx2967_wdt.c | 279 |
1 files changed, 0 insertions, 279 deletions
diff --git a/drivers/watchdog/zx2967_wdt.c b/drivers/watchdog/zx2967_wdt.c deleted file mode 100644 index bf183e73671a..000000000000 --- a/drivers/watchdog/zx2967_wdt.c +++ /dev/null @@ -1,279 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * watchdog driver for ZTE's zx2967 family - * - * Copyright (C) 2017 ZTE Ltd. - * - * Author: Baoyou Xie <baoyou.xie@linaro.org> - */ - -#include <linux/clk.h> -#include <linux/io.h> -#include <linux/mfd/syscon.h> -#include <linux/module.h> -#include <linux/of_address.h> -#include <linux/platform_device.h> -#include <linux/regmap.h> -#include <linux/reset.h> -#include <linux/watchdog.h> - -#define ZX2967_WDT_CFG_REG 0x4 -#define ZX2967_WDT_LOAD_REG 0x8 -#define ZX2967_WDT_REFRESH_REG 0x18 -#define ZX2967_WDT_START_REG 0x1c - -#define ZX2967_WDT_REFRESH_MASK GENMASK(5, 0) - -#define ZX2967_WDT_CFG_DIV(n) ((((n) & 0xff) - 1) << 8) -#define ZX2967_WDT_START_EN 0x1 - -/* - * Hardware magic number. - * When watchdog reg is written, the lowest 16 bits are valid, but - * the highest 16 bits should be always this number. - */ -#define ZX2967_WDT_WRITEKEY (0x1234 << 16) -#define ZX2967_WDT_VAL_MASK GENMASK(15, 0) - -#define ZX2967_WDT_DIV_DEFAULT 16 -#define ZX2967_WDT_DEFAULT_TIMEOUT 32 -#define ZX2967_WDT_MIN_TIMEOUT 1 -#define ZX2967_WDT_MAX_TIMEOUT 524 -#define ZX2967_WDT_MAX_COUNT 0xffff - -#define ZX2967_WDT_CLK_FREQ 0x8000 - -#define ZX2967_WDT_FLAG_REBOOT_MON BIT(0) - -struct zx2967_wdt { - struct watchdog_device wdt_device; - void __iomem *reg_base; - struct clk *clock; -}; - -static inline u32 zx2967_wdt_readl(struct zx2967_wdt *wdt, u16 reg) -{ - return readl_relaxed(wdt->reg_base + reg); -} - -static inline void zx2967_wdt_writel(struct zx2967_wdt *wdt, u16 reg, u32 val) -{ - writel_relaxed(val | ZX2967_WDT_WRITEKEY, wdt->reg_base + reg); -} - -static void zx2967_wdt_refresh(struct zx2967_wdt *wdt) -{ - u32 val; - - val = zx2967_wdt_readl(wdt, ZX2967_WDT_REFRESH_REG); - /* - * Bit 4-5, 1 and 2: refresh config info - * Bit 2-3, 1 and 2: refresh counter - * Bit 0-1, 1 and 2: refresh int-value - * we shift each group value between 1 and 2 to refresh all data. - */ - val ^= ZX2967_WDT_REFRESH_MASK; - zx2967_wdt_writel(wdt, ZX2967_WDT_REFRESH_REG, - val & ZX2967_WDT_VAL_MASK); -} - -static int -zx2967_wdt_set_timeout(struct watchdog_device *wdd, unsigned int timeout) -{ - struct zx2967_wdt *wdt = watchdog_get_drvdata(wdd); - unsigned int divisor = ZX2967_WDT_DIV_DEFAULT; - u32 count; - - count = timeout * ZX2967_WDT_CLK_FREQ; - if (count > divisor * ZX2967_WDT_MAX_COUNT) - divisor = DIV_ROUND_UP(count, ZX2967_WDT_MAX_COUNT); - count = DIV_ROUND_UP(count, divisor); - zx2967_wdt_writel(wdt, ZX2967_WDT_CFG_REG, - ZX2967_WDT_CFG_DIV(divisor) & ZX2967_WDT_VAL_MASK); - zx2967_wdt_writel(wdt, ZX2967_WDT_LOAD_REG, - count & ZX2967_WDT_VAL_MASK); - zx2967_wdt_refresh(wdt); - wdd->timeout = (count * divisor) / ZX2967_WDT_CLK_FREQ; - - return 0; -} - -static void __zx2967_wdt_start(struct zx2967_wdt *wdt) -{ - u32 val; - - val = zx2967_wdt_readl(wdt, ZX2967_WDT_START_REG); - val |= ZX2967_WDT_START_EN; - zx2967_wdt_writel(wdt, ZX2967_WDT_START_REG, - val & ZX2967_WDT_VAL_MASK); -} - -static void __zx2967_wdt_stop(struct zx2967_wdt *wdt) -{ - u32 val; - - val = zx2967_wdt_readl(wdt, ZX2967_WDT_START_REG); - val &= ~ZX2967_WDT_START_EN; - zx2967_wdt_writel(wdt, ZX2967_WDT_START_REG, - val & ZX2967_WDT_VAL_MASK); -} - -static int zx2967_wdt_start(struct watchdog_device *wdd) -{ - struct zx2967_wdt *wdt = watchdog_get_drvdata(wdd); - - zx2967_wdt_set_timeout(wdd, wdd->timeout); - __zx2967_wdt_start(wdt); - - return 0; -} - -static int zx2967_wdt_stop(struct watchdog_device *wdd) -{ - struct zx2967_wdt *wdt = watchdog_get_drvdata(wdd); - - __zx2967_wdt_stop(wdt); - - return 0; -} - -static int zx2967_wdt_keepalive(struct watchdog_device *wdd) -{ - struct zx2967_wdt *wdt = watchdog_get_drvdata(wdd); - - zx2967_wdt_refresh(wdt); - - return 0; -} - -#define ZX2967_WDT_OPTIONS \ - (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE) -static const struct watchdog_info zx2967_wdt_ident = { - .options = ZX2967_WDT_OPTIONS, - .identity = "zx2967 watchdog", -}; - -static const struct watchdog_ops zx2967_wdt_ops = { - .owner = THIS_MODULE, - .start = zx2967_wdt_start, - .stop = zx2967_wdt_stop, - .ping = zx2967_wdt_keepalive, - .set_timeout = zx2967_wdt_set_timeout, -}; - -static void zx2967_wdt_reset_sysctrl(struct device *dev) -{ - int ret; - void __iomem *regmap; - unsigned int offset, mask, config; - struct of_phandle_args out_args; - - ret = of_parse_phandle_with_fixed_args(dev->of_node, - "zte,wdt-reset-sysctrl", 3, 0, &out_args); - if (ret) - return; - - offset = out_args.args[0]; - config = out_args.args[1]; - mask = out_args.args[2]; - - regmap = syscon_node_to_regmap(out_args.np); - if (IS_ERR(regmap)) { - of_node_put(out_args.np); - return; - } - - regmap_update_bits(regmap, offset, mask, config); - of_node_put(out_args.np); -} - -static void zx2967_clk_disable_unprepare(void *data) -{ - clk_disable_unprepare(data); -} - -static int zx2967_wdt_probe(struct platform_device *pdev) -{ - struct device *dev = &pdev->dev; - struct zx2967_wdt *wdt; - int ret; - struct reset_control *rstc; - - wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); - if (!wdt) - return -ENOMEM; - - platform_set_drvdata(pdev, wdt); - - wdt->wdt_device.info = &zx2967_wdt_ident; - wdt->wdt_device.ops = &zx2967_wdt_ops; - wdt->wdt_device.timeout = ZX2967_WDT_DEFAULT_TIMEOUT; - wdt->wdt_device.max_timeout = ZX2967_WDT_MAX_TIMEOUT; - wdt->wdt_device.min_timeout = ZX2967_WDT_MIN_TIMEOUT; - wdt->wdt_device.parent = dev; - - wdt->reg_base = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(wdt->reg_base)) - return PTR_ERR(wdt->reg_base); - - zx2967_wdt_reset_sysctrl(dev); - - wdt->clock = devm_clk_get(dev, NULL); - if (IS_ERR(wdt->clock)) { - dev_err(dev, "failed to find watchdog clock source\n"); - return PTR_ERR(wdt->clock); - } - - ret = clk_prepare_enable(wdt->clock); - if (ret < 0) { - dev_err(dev, "failed to enable clock\n"); - return ret; - } - ret = devm_add_action_or_reset(dev, zx2967_clk_disable_unprepare, - wdt->clock); - if (ret) - return ret; - clk_set_rate(wdt->clock, ZX2967_WDT_CLK_FREQ); - - rstc = devm_reset_control_get_exclusive(dev, NULL); - if (IS_ERR(rstc)) { - dev_err(dev, "failed to get rstc"); - return PTR_ERR(rstc); - } - - reset_control_assert(rstc); - reset_control_deassert(rstc); - - watchdog_set_drvdata(&wdt->wdt_device, wdt); - watchdog_init_timeout(&wdt->wdt_device, - ZX2967_WDT_DEFAULT_TIMEOUT, dev); - watchdog_set_nowayout(&wdt->wdt_device, WATCHDOG_NOWAYOUT); - - ret = devm_watchdog_register_device(dev, &wdt->wdt_device); - if (ret) - return ret; - - dev_info(dev, "watchdog enabled (timeout=%d sec, nowayout=%d)", - wdt->wdt_device.timeout, WATCHDOG_NOWAYOUT); - - return 0; -} - -static const struct of_device_id zx2967_wdt_match[] = { - { .compatible = "zte,zx296718-wdt", }, - {} -}; -MODULE_DEVICE_TABLE(of, zx2967_wdt_match); - -static struct platform_driver zx2967_wdt_driver = { - .probe = zx2967_wdt_probe, - .driver = { - .name = "zx2967-wdt", - .of_match_table = of_match_ptr(zx2967_wdt_match), - }, -}; -module_platform_driver(zx2967_wdt_driver); - -MODULE_AUTHOR("Baoyou Xie <baoyou.xie@linaro.org>"); -MODULE_DESCRIPTION("ZTE zx2967 Watchdog Device Driver"); -MODULE_LICENSE("GPL v2"); |