From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from canuck.infradead.org ([2001:4978:20e::1]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1Si0Z6-0007rd-90 for barebox@lists.infradead.org; Fri, 22 Jun 2012 09:54:08 +0000 Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by canuck.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1Si0Z4-0004jh-Rj for barebox@lists.infradead.org; Fri, 22 Jun 2012 09:54:08 +0000 Received: from dude.hi.pengutronix.de ([2001:6f8:1178:2:21e:67ff:fe11:9c5c]) by metis.ext.pengutronix.de with esmtp (Exim 4.72) (envelope-from ) id 1Si0Z2-0006zc-Nz for barebox@lists.infradead.org; Fri, 22 Jun 2012 11:54:04 +0200 Received: from jbe by dude.hi.pengutronix.de with local (Exim 4.80) (envelope-from ) id 1Si0Z2-0001PN-MN for barebox@lists.infradead.org; Fri, 22 Jun 2012 11:54:04 +0200 From: Juergen Beisert Date: Fri, 22 Jun 2012 11:54:03 +0200 Message-Id: <1340358843-30614-3-git-send-email-jbe@pengutronix.de> In-Reply-To: <1340358843-30614-1-git-send-email-jbe@pengutronix.de> References: <1340358843-30614-1-git-send-email-jbe@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 2/2] ARM/MXS: add a watchdog driver for i.MX28 To: barebox@lists.infradead.org Signed-off-by: Juergen Beisert --- drivers/watchdog/Kconfig | 7 +++ drivers/watchdog/Makefile | 1 + drivers/watchdog/im28wd.c | 121 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 129 insertions(+) create mode 100644 drivers/watchdog/im28wd.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index b5970c9..b1a73c0 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -7,4 +7,11 @@ if WATCHDOG config WATCHDOG_CORE bool +config WATCHDOG_MXS28 + bool "i.MX28" + depends on ARCH_IMX28 + select WATCHDOG_CORE + help + Add support for watchdog management for the i.MX28 SoC. + endif diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 7a446d7..b0d4d2a 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_WATCHDOG_CORE) += wd_core.o +obj-$(CONFIG_WATCHDOG_MXS28) += im28wd.o diff --git a/drivers/watchdog/im28wd.c b/drivers/watchdog/im28wd.c new file mode 100644 index 0000000..b1c4809 --- /dev/null +++ b/drivers/watchdog/im28wd.c @@ -0,0 +1,121 @@ +/* + * (c) 2012 Juergen Beisert + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Note: this driver works for the i.MX28 SoC. It might work for the + * i.MX23 Soc as well, but is not tested yet. + */ + +#include +#include +#include +#include +#include + +#define MXS_RTC_CTRL 0x0 +#define MXS_RTC_SET_ADDR 0x4 +#define MXS_RTC_CLR_ADDR 0x8 +# define MXS_RTC_CTRL_WATCHDOGEN (1 << 4) + +#define MXS_RTC_STAT 0x10 +# define MXS_RTC_STAT_WD_PRESENT (1 << 29) + +#define MXS_RTC_WATCHDOG 0x50 + +#define MXS_RTC_PERSISTENT0 0x60 +/* dubious meaning from inside the SoC's firmware ROM */ +# define MXS_RTC_PERSISTENT0_EXT_RST (1 << 21) +/* dubious meaning from inside the SoC's firmware ROM */ +# define MXS_RTC_PERSISTENT0_THM_RST (1 << 20) + +#define MXS_RTC_PERSISTENT1 0x70 +/* dubious meaning from inside the SoC's firmware ROM */ +# define MXS_RTC_PERSISTENT1_FORCE_UPDATER (1 << 31) + +#define MXS_RTC_DEBUG 0xc0 + +#define WDOG_TICK_RATE 1000 /* the watchdog uses a 1 kHz clock rate */ + +struct imx28_wd { + void __iomem *regs; + u32 timeout; +}; + +static struct imx28_wd *wd; + +/* note: 'timeout' in clock ticks */ +static void imx28_wd_set_timeout(const struct imx28_wd *p, unsigned timeout) +{ + void __iomem *base; + + if (timeout) { + writel(timeout, p->regs + MXS_RTC_WATCHDOG); + base = p->regs + MXS_RTC_SET_ADDR; + } else { + base = p->regs + MXS_RTC_CLR_ADDR; + } + writel(MXS_RTC_CTRL_WATCHDOGEN, base + MXS_RTC_CTRL); + writel(MXS_RTC_PERSISTENT1_FORCE_UPDATER, base + MXS_RTC_PERSISTENT1); +} + +/* note: 'timeout' in [seconds] */ +int watchdog_set_timeout(unsigned timeout) +{ + if (timeout > (ULONG_MAX / WDOG_TICK_RATE)) + return -EINVAL; + + imx28_wd_set_timeout(wd, timeout * WDOG_TICK_RATE); + return 0; +} +EXPORT_SYMBOL(watchdog_set_timeout); + +static int imx28_wd_probe(struct device_d *dev) +{ + struct imx28_wd *priv; + + priv = xzalloc(sizeof(struct imx28_wd)); + priv->regs = dev_request_mem_region(dev, 0); + priv->timeout = 20; + dev->priv = priv; + wd = priv; + + if (!(readl(priv->regs + MXS_RTC_STAT) & MXS_RTC_STAT_WD_PRESENT)) { + free(priv); + return -ENODEV; + } + + /* disable the debug feature to ensure a working WD */ + writel(0x00000000, priv->regs + MXS_RTC_DEBUG); + + return 0; +} + +static void imx28_wd_remove(struct device_d *dev) +{ + struct imx28_wd *priv= dev->priv; + wd = NULL; + free(priv); +} + +static struct driver_d imx28_wd_driver = { + .name = "im28wd", + .probe = imx28_wd_probe, + .remove = imx28_wd_remove, +}; + +static int imx28_wd_init(void) +{ + register_driver(&imx28_wd_driver); + return 0; +} + +device_initcall(imx28_wd_init); -- 1.7.10 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox