From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751161AbdAPP0C (ORCPT ); Mon, 16 Jan 2017 10:26:02 -0500 Received: from mail-pg0-f46.google.com ([74.125.83.46]:35448 "EHLO mail-pg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038AbdAPPZ7 (ORCPT ); Mon, 16 Jan 2017 10:25:59 -0500 Subject: Re: [PATCH v1 3/3] watchdog: zx2967: add watchdog controller driver for ZTE's zx2967 family To: Baoyou Xie , wim@iguana.be, linux@roeck-us.net, robh+dt@kernel.org, mark.rutland@arm.com References: <1484540395-3335-1-git-send-email-baoyou.xie@linaro.org> <1484540395-3335-3-git-send-email-baoyou.xie@linaro.org> Cc: linux-arm-kernel@lists.infradead.org, linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, shawnguo@kernel.org, xie.baoyou@zte.com.cn, chen.chaokai@zte.com.cn, wang.qiang01@zte.com.cn From: Jun Nie Message-ID: <464a75ef-d3c5-9b17-3e73-12ca3cbdb69f@linaro.org> Date: Mon, 16 Jan 2017 23:25:52 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <1484540395-3335-3-git-send-email-baoyou.xie@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017年01月16日 12:19, Baoyou Xie wrote: > This patch adds watchdog controller driver for ZTE's zx2967 family. > > Signed-off-by: Baoyou Xie > --- > drivers/watchdog/Kconfig | 10 ++ > drivers/watchdog/Makefile | 1 + > drivers/watchdog/zx2967_wdt.c | 405 ++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 416 insertions(+) > create mode 100644 drivers/watchdog/zx2967_wdt.c > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 3eb58cb..79027da 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -714,6 +714,16 @@ config ASPEED_WATCHDOG > To compile this driver as a module, choose M here: the > module will be called aspeed_wdt. > > +config ZX2967_WATCHDOG > + tristate "ZTE zx2967 SoCs watchdog support" > + depends on ARCH_ZX > + select WATCHDOG_CORE > + help > + Say Y here to include support for the watchdog timer > + in ZTE zx2967 SoCs. > + To compile this driver as a module, choose M here: the > + module will be called zx2967_wdt. > + > # AVR32 Architecture > > config AT32AP700X_WDT > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index caa9f4a..ea08925 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -82,6 +82,7 @@ obj-$(CONFIG_BCM7038_WDT) += bcm7038_wdt.o > obj-$(CONFIG_ATLAS7_WATCHDOG) += atlas7_wdt.o > obj-$(CONFIG_RENESAS_WDT) += renesas_wdt.o > obj-$(CONFIG_ASPEED_WATCHDOG) += aspeed_wdt.o > +obj-$(CONFIG_ZX2967_WATCHDOG) += zx2967_wdt.o > > # AVR32 Architecture > obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o > diff --git a/drivers/watchdog/zx2967_wdt.c b/drivers/watchdog/zx2967_wdt.c > new file mode 100644 > index 0000000..8791dd2 > --- /dev/null > +++ b/drivers/watchdog/zx2967_wdt.c > @@ -0,0 +1,405 @@ > +/* > + * watchdog driver for ZTE's zx2967 family > + * > + * Copyright (C) 2017 ZTE Ltd. > + * > + * Author: Baoyou Xie > + * > + * License terms: GNU General Public License (GPL) version 2 > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#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 0x3f > + > +#define ZX2967_WDT_CFG_DIV(n) ((((n)&0xff) - 1) << 8) > +#define ZX2967_WDT_START_EN 0x1 > + > +#define ZX2967_WDT_WRITEKEY 0x12340000 > + > +#define ZX2967_WDT_DIV_DEFAULT 16 > +#define ZX2967_WDT_DEFAULT_TIMEOUT 32 > +#define ZX2967_WDT_MIN_TIMEOUT 1 > +#define ZX2967_WDT_MAX_TIMEOUT 500 > +#define ZX2967_WDT_MAX_COUNT 0xffff > + > +#define ZX2967_WDT_FLAG_REBOOT_MON (1 << 0) > + > +#define ZX2967_RESET_MASK_REG 0xb0 > + > +#define zx2967_wdt_write_reg(v, r) \ > + writel((v) | ZX2967_WDT_WRITEKEY, r) > +#define zx2967_wdt_read_reg(r) readl(r) For writel and readl, *_relaxed is recommended. > + > +static bool nowayout = WATCHDOG_NOWAYOUT; > +static unsigned int timeout = ZX2967_WDT_DEFAULT_TIMEOUT; > + > +struct zx2967_wdt { > + struct device *dev; > + struct clk *clock; > + void __iomem *reg_base; > + unsigned int conf; > + unsigned int load; > + unsigned int flags; > + spinlock_t lock; > + struct watchdog_device wdt_device; > + struct notifier_block restart_handler; > + struct notifier_block reboot_handler; > +}; > + > +static void zx2967_wdt_refresh(struct zx2967_wdt *wdt) > +{ > + unsigned int val; > + > + spin_lock(&wdt->lock); > + > + val = zx2967_wdt_read_reg(wdt->reg_base + ZX2967_WDT_REFRESH_REG); > + val ^= ZX2967_WDT_REFRESH_MASK; > + zx2967_wdt_write_reg(val, wdt->reg_base + ZX2967_WDT_REFRESH_REG); > + > + spin_unlock(&wdt->lock); > +} > + > +static void __zx2967_wdt_stop(struct zx2967_wdt *wdt) > +{ > + unsigned int val; > + > + spin_lock(&wdt->lock); > + > + val = zx2967_wdt_read_reg(wdt->reg_base + ZX2967_WDT_START_REG); > + val &= ~(ZX2967_WDT_START_EN); > + zx2967_wdt_write_reg(val, wdt->reg_base + ZX2967_WDT_START_REG); > + > + spin_unlock(&wdt->lock); > +} > + > +static void __zx2967_wdt_start(struct zx2967_wdt *wdt) > +{ > + unsigned int val; > + > + spin_lock(&wdt->lock); > + > + val = zx2967_wdt_read_reg(wdt->reg_base + ZX2967_WDT_START_REG); > + val |= ZX2967_WDT_START_EN; > + zx2967_wdt_write_reg(val, wdt->reg_base + ZX2967_WDT_START_REG); > + > + spin_unlock(&wdt->lock); > +} > + > +static unsigned int > +__zx2967_wdt_set_timeout(struct zx2967_wdt *wdt, unsigned int timeout) > +{ > + unsigned int freq = clk_get_rate(wdt->clock); > + unsigned int divisor = ZX2967_WDT_DIV_DEFAULT, count; > + > + count = timeout * 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_write_reg(ZX2967_WDT_CFG_DIV(divisor), > + wdt->reg_base + ZX2967_WDT_CFG_REG); > + zx2967_wdt_write_reg(count, wdt->reg_base + ZX2967_WDT_LOAD_REG); No spin lock here. Do we really need the spin lock? > + zx2967_wdt_refresh(wdt); > + > + wdt->load = count; > + dev_info(wdt->dev, "count=%d, timeout=%d, divisor=%d\n", > + count, timeout, divisor); > + > + return (count * divisor) / freq; > +} > + > +static int zx2967_wdt_set_timeout(struct watchdog_device *wdd, > + unsigned int timeout) > +{ > + struct zx2967_wdt *wdt = watchdog_get_drvdata(wdd); > + > + if (watchdog_timeout_invalid(&wdt->wdt_device, timeout)) { > + dev_err(wdt->dev, "timeout %d is invalid\n", timeout); > + > + return -EINVAL; > + } > + > + wdd->timeout = __zx2967_wdt_set_timeout(wdt, timeout); > + > + return 0; > +} > + > +static int zx2967_wdt_start(struct watchdog_device *wdd) > +{ > + struct zx2967_wdt *wdt = watchdog_get_drvdata(wdd); > + > + __zx2967_wdt_stop(wdt); > + 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, > + .firmware_version = 0, > + .identity = "zx2967 watchdog", > +}; > + > +static 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_fix_sysdown(struct zx2967_wdt *wdt) > +{ > + __zx2967_wdt_stop(wdt); > + __zx2967_wdt_set_timeout(wdt, 15); > + __zx2967_wdt_start(wdt); > +} > + > +static int zx2967_wdt_notify_sys(struct notifier_block *this, > + unsigned long code, void *unused) > +{ > + struct zx2967_wdt *wdt = container_of(this, struct zx2967_wdt, > + reboot_handler); > + > + wdt->flags |= ZX2967_WDT_FLAG_REBOOT_MON; > + switch (code) { > + case SYS_HALT: > + case SYS_POWER_OFF: > + case SYS_RESTART: > + zx2967_wdt_fix_sysdown(wdt); > + break; > + default: > + break; > + } > + > + return 0; > +} > + > +static int zx2967_wdt_restart(struct notifier_block *this, > + unsigned long mode, void *cmd) > +{ > + struct zx2967_wdt *wdt; > + > + wdt = container_of(this, struct zx2967_wdt, restart_handler); > + > + zx2967_wdt_stop(&wdt->wdt_device); > + > + zx2967_wdt_write_reg(0x80, wdt->reg_base + ZX2967_WDT_LOAD_REG); > + zx2967_wdt_refresh(wdt); > + zx2967_wdt_write_reg(ZX2967_WDT_START_EN, > + wdt->reg_base + ZX2967_WDT_START_REG); > + > + zx2967_wdt_start(&wdt->wdt_device); > + /* wait for reset*/ > + mdelay(500); > + > + return NOTIFY_DONE; > +} > + > +static void zx2967_reset_mask_config(struct device *dev) > +{ > + struct device_node *np = NULL; > + void __iomem *reg; > + unsigned int val, mask, config, size; > + const unsigned int *prop; > + > + prop = of_get_property(dev->of_node, "reset-mask-config", &size); > + if (size < (sizeof(*prop) * 2)) { > + dev_err(dev, "bad data for reset-mask-config"); > + return; > + } > + config = be32_to_cpup(prop++); > + mask = be32_to_cpup(prop); > + np = of_find_compatible_node(NULL, NULL, "zte,aon-sysctrl"); > + if (!np) { > + dev_err(dev, "Cannot found pcu device node\n"); > + return; > + } > + reg = of_iomap(np, 0) + ZX2967_RESET_MASK_REG; > + of_node_put(np); > + > + val = readl(reg); > + val &= ~mask; > + val |= config; > + writel(val, reg); > +} > + > +static int zx2967_wdt_probe(struct platform_device *pdev) > +{ > + struct device *dev; > + struct zx2967_wdt *wdt; > + struct resource *base; > + int err, ret = 0; > + unsigned int rate, val; > + > + struct reset_control *rstc; > + > + dev = &pdev->dev; > + > + wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); > + if (!wdt) { > + ret = -ENOMEM; > + goto out; > + } > + > + platform_set_drvdata(pdev, wdt); > + > + wdt->dev = dev; > + spin_lock_init(&wdt->lock); > + > + 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 = &pdev->dev; > + > + base = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + wdt->reg_base = devm_ioremap_resource(dev, base); > + > + if (of_find_property(dev->of_node, "reset-mask-config", NULL)) > + zx2967_reset_mask_config(dev); > + > + wdt->reboot_handler.notifier_call = zx2967_wdt_notify_sys; > + ret = register_reboot_notifier(&wdt->reboot_handler); > + wdt->clock = devm_clk_get(dev, "wdtclk"); > + if (IS_ERR(wdt->clock)) { > + dev_err(dev, "failed to find watchdog clock source\n"); > + ret = PTR_ERR(wdt->clock); > + goto out; > + } > + ret = clk_prepare_enable(wdt->clock); > + if (ret < 0) { > + dev_err(dev, "failed to enable clock\n"); > + goto out; > + } > + > + rate = clk_get_rate(wdt->clock); > + if (rate == 24000000) > + ret = clk_set_rate(wdt->clock, 32768); > + rate = clk_get_rate(wdt->clock); Do you want to check rate again? Or you want to just check set_rate return value? > + > + rstc = devm_reset_control_get(dev, "wdtrst"); > + if (!rstc) { > + dev_info(dev, "rstc get failed"); dev_err() may be more feasible. > + } else { > + reset_control_assert(rstc); > + mdelay(10); > + reset_control_deassert(rstc); > + } > + > + watchdog_set_drvdata(&wdt->wdt_device, wdt); > + > + watchdog_init_timeout(&wdt->wdt_device, timeout, &pdev->dev); > + watchdog_set_nowayout(&wdt->wdt_device, nowayout); > + > + zx2967_wdt_stop(&wdt->wdt_device); > + > + err = watchdog_register_device(&wdt->wdt_device); > + if (unlikely(err)) { > + ret = err; > + goto fail_register; > + } > + > + wdt->restart_handler.notifier_call = zx2967_wdt_restart; > + wdt->restart_handler.priority = 128; > + ret = register_restart_handler(&wdt->restart_handler); > + if (ret) { > + pr_err("cannot register restart handler, %d\n", ret); > + goto fail_restart; > + } > + > + val = zx2967_wdt_read_reg(wdt->reg_base + ZX2967_WDT_START_REG); > + dev_info(&pdev->dev, "watchdog enabled (timeout=%d sec, nowayout=%d)", > + wdt->wdt_device.timeout, nowayout); > + > + return 0; > + > +fail_restart: > + watchdog_unregister_device(&wdt->wdt_device); > +fail_register: > + clk_disable_unprepare(wdt->clock); > +out: > + return ret; > +} > + > +static int zx2967_wdt_remove(struct platform_device *pdev) > +{ > + struct zx2967_wdt *wdt = platform_get_drvdata(pdev); > + > + unregister_restart_handler(&wdt->restart_handler); > + watchdog_unregister_device(&wdt->wdt_device); > + clk_disable_unprepare(wdt->clock); > + > + return 0; > +} > + > +static void zx2967_wdt_shutdown(struct platform_device *pdev) > +{ > + struct zx2967_wdt *wdt = platform_get_drvdata(pdev); > + > + if (!(wdt->flags & ZX2967_WDT_FLAG_REBOOT_MON)) > + zx2967_wdt_stop(&wdt->wdt_device); > +} > + > +static const struct of_device_id zx2967_wdt_match[] = { > + { .compatible = "zte,zx296718-wdt", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, zx2967_wdt_match); > + > +static const struct platform_device_id zx2967_wdt_ids[] = { > + { .name = "zx2967-wdt", }, > + {} > +}; > +MODULE_DEVICE_TABLE(platform, zx2967_wdt_ids); > + > +static struct platform_driver zx2967_wdt_driver = { > + .probe = zx2967_wdt_probe, > + .remove = zx2967_wdt_remove, > + .shutdown = zx2967_wdt_shutdown, > + .id_table = zx2967_wdt_ids, > + .driver = { > + .name = "zx2967-wdt", > + .of_match_table = of_match_ptr(zx2967_wdt_match), > + }, > +}; > +module_platform_driver(zx2967_wdt_driver); > + > +MODULE_AUTHOR("Baoyou Xie "); > +MODULE_DESCRIPTION("ZTE zx2967 Watchdog Device Driver"); > +MODULE_LICENSE("GPL"); >