From 33a2ee4d019adc99b461c05fc19fa18a3174e7c0 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Mon, 9 May 2005 14:32:04 -0700 Subject: [PATCH] Add OMAP watchdog driver Adds OMAP watchdog driver. Signed-off-by: Tony Lindgren --- drivers/char/watchdog/Kconfig | 7 + drivers/char/watchdog/Makefile | 1 + drivers/char/watchdog/omap1610_wdt.c | 243 +++++++++++++++++++++++++++ drivers/char/watchdog/omap1610_wdt.h | 52 ++++++ 4 files changed, 303 insertions(+) create mode 100644 drivers/char/watchdog/omap1610_wdt.c create mode 100644 drivers/char/watchdog/omap1610_wdt.h diff --git a/drivers/char/watchdog/Kconfig b/drivers/char/watchdog/Kconfig index 06a31da2381..9e38cc4accf 100644 --- a/drivers/char/watchdog/Kconfig +++ b/drivers/char/watchdog/Kconfig @@ -546,4 +546,11 @@ config USBPCWATCHDOG Most people will say N. +config OMAP16XX_WATCHDOG + tristate "OMAP1610/OMAP1710 Watchdog" + depends on WATCHDOG && ARCH_OMAP16XX + help + Support for TI OMAP1610/OMAP1710 watchdog. Say 'Y' here to enable the + OMAP1610/OMAP1710 watchdog timer. + endmenu diff --git a/drivers/char/watchdog/Makefile b/drivers/char/watchdog/Makefile index 1cd27efa35c..568572162e4 100644 --- a/drivers/char/watchdog/Makefile +++ b/drivers/char/watchdog/Makefile @@ -33,6 +33,7 @@ obj-$(CONFIG_USBPCWATCHDOG) += pcwd_usb.o obj-$(CONFIG_IXP4XX_WATCHDOG) += ixp4xx_wdt.o obj-$(CONFIG_IXP2000_WATCHDOG) += ixp2000_wdt.o obj-$(CONFIG_8xx_WDT) += mpc8xx_wdt.o +obj-$(CONFIG_OMAP16XX_WATCHDOG) += omap1610_wdt.o # Only one watchdog can succeed. We probe the hardware watchdog # drivers first, then the softdog driver. This means if your hardware diff --git a/drivers/char/watchdog/omap1610_wdt.c b/drivers/char/watchdog/omap1610_wdt.c new file mode 100644 index 00000000000..e610e400154 --- /dev/null +++ b/drivers/char/watchdog/omap1610_wdt.c @@ -0,0 +1,243 @@ +/* + * linux/drivers/char/omap1610_wdt.c + * + * Watchdog driver for the TI OMAP + * + * Author: MontaVista Software, Inc. + * or + * + * 2003 (c) MontaVista Software, Inc. This file is licensed under the + * terms of the GNU General Public License version 2. This program is + * licensed "as is" without any warranty of any kind, whether express + * or implied. + * + * History: + * + * 20030527: George G. Davis + * Initially based on linux-2.4.19-rmk7-pxa1/drivers/char/sa1100_wdt.c + * (c) Copyright 2000 Oleg Drokin + * Based on SoftDog driver by Alan Cox + * + * Copyright (c) 2004 Texas Instruments. + * + * 1. Modified to support OMAP1610 32-KHz watchdog timer + * 2. Ported to 2.6 kernel + * + * + * TODO: + * 1. Need to disable watchdog when entering chip idle mode. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include "omap1610_wdt.h" + +static int timer_margin; /* in seconds */ +static int pre_margin; +static int omap_wdt_users; +static struct clk *armwdt_ck = 0; +static struct miscdevice omap_wdt_miscdev; /* Forward declaration */ + +static unsigned int wdt_trgr_pattern = 0x1234; + +static void +omap_wdt_ping(void) +{ + while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x08) ; /* wait for posted write to complete */ + wdt_trgr_pattern = ~wdt_trgr_pattern; + omap_writel(wdt_trgr_pattern, (OMAP_WATCHDOG_TGR)); + while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x08) ; /* wait for posted write to complete */ + return; +} + +static void +omap_wdt_enable(void) +{ + /* Sequence to enable the watchdog */ + omap_writel(0xBBBB, OMAP_WATCHDOG_SPR); + while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10) ; + omap_writel(0x4444, OMAP_WATCHDOG_SPR); + while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10) ; + return; +} + +static void +omap_wdt_disable(void) +{ + /* sequence required to disable watchdog */ + omap_writel(0xAAAA, OMAP_WATCHDOG_SPR); /* TIMER_MODE */ + while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10) ; + omap_writel(0x5555, OMAP_WATCHDOG_SPR); /* TIMER_MODE */ + while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10) ; + return; +} + +/* + * Allow only one person to hold it open + */ + +static int +omap_wdt_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(1, (unsigned long *) &omap_wdt_users)) + return -EBUSY; + + if (armwdt_ck == 0 || IS_ERR(armwdt_ck)) { + armwdt_ck = clk_get(omap_wdt_miscdev.dev, "armwdt_ck"); + if (IS_ERR(armwdt_ck)) { + omap_wdt_users = 0; + return PTR_ERR(armwdt_ck); + } + clk_use(armwdt_ck); /* Enable the clock */ + } + + omap_wdt_enable(); + + return 0; +} + +static int +omap_wdt_release(struct inode *inode, struct file *file) +{ + /* + * Shut off the timer. + * Lock it in if it's a module and we defined ...NOWAYOUT + */ +#ifndef CONFIG_WATCHDOG_NOWAYOUT + omap_wdt_disable(); + clk_unuse(armwdt_ck); /* Disable the clock */ + clk_put(armwdt_ck); + armwdt_ck = 0; +#endif + omap_wdt_users = 0; + return 0; +} + +static ssize_t +omap_wdt_write(struct file *file, const char *data, size_t len, loff_t * ppos) +{ + /* Can't seek (pwrite) on this device */ + if (ppos != &file->f_pos) + return -ESPIPE; + + /* Refresh LOAD_TIME. */ + if (len) { + omap_wdt_ping(); + return 1; + } + return 0; +} + +static int +omap_wdt_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + int new_margin; + static struct watchdog_info ident = { + .identity = "OMAP Watchdog", + .options = WDIOF_SETTIMEOUT, + .firmware_version = 0, + }; + + switch (cmd) { + default: + return -ENOIOCTLCMD; + case WDIOC_GETSUPPORT: + return copy_to_user((struct watchdog_info *) arg, &ident, + sizeof (ident)); + case WDIOC_GETSTATUS: + return put_user(0, (int *) arg); + case WDIOC_GETBOOTSTATUS: + return put_user(omap_readw(ARM_SYSST), (int *) arg); + case WDIOC_KEEPALIVE: + omap_wdt_ping(); + return 0; + case WDIOC_SETTIMEOUT: + if (get_user(new_margin, (int *) arg)) + return -EFAULT; + if ((new_margin < TIMER_MARGIN_MIN) + || (new_margin > TIMER_MARGIN_MAX)) + timer_margin = TIMER_MARGIN_MAX; /* default timeout */ + else + timer_margin = new_margin; + pre_margin = GET_WLDR_VAL(timer_margin); + + omap_wdt_disable(); + + while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x04) ; /* wait for posted write to complete */ + omap_writel(pre_margin, (OMAP_WATCHDOG_LDR)); + while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x04) ; /* wait for posted write to complete */ + + omap_wdt_enable(); + + omap_wdt_ping(); + /* Fall */ + case WDIOC_GETTIMEOUT: + return put_user(timer_margin, (int *) arg); + } +} + +static struct file_operations omap_wdt_fops = { + .owner = THIS_MODULE, + .write = omap_wdt_write, + .ioctl = omap_wdt_ioctl, + .open = omap_wdt_open, + .release = omap_wdt_release, +}; + +static struct miscdevice omap_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "omap_wdt", + .fops = &omap_wdt_fops +}; + +static int __init +omap_wdt_init(void) +{ + int ret; + + ret = misc_register(&omap_wdt_miscdev); + + if (ret) + return ret; + + omap_wdt_disable(); + + if (timer_margin < 1 || timer_margin > 32) + timer_margin = 32; + + printk(KERN_INFO "%s: TI OMAP Watchdog Timer: timer margin %d sec\n", + omap_wdt_miscdev.name, timer_margin); + + return 0; +} + +static void __exit +omap_wdt_exit(void) +{ + misc_deregister(&omap_wdt_miscdev); +} + +module_init(omap_wdt_init); +module_exit(omap_wdt_exit); + +MODULE_AUTHOR("George G. Davis"); +MODULE_LICENSE("GPL"); +module_param(timer_margin, int, 0); diff --git a/drivers/char/watchdog/omap1610_wdt.h b/drivers/char/watchdog/omap1610_wdt.h new file mode 100644 index 00000000000..48a0e80ef52 --- /dev/null +++ b/drivers/char/watchdog/omap1610_wdt.h @@ -0,0 +1,52 @@ +/* + * linux/drivers/char/watchdog/omap1610_wdt.h + * + * BRIEF MODULE DESCRIPTION + * OMAP Watchdog timer register definitions + * + * Copyright (C) 2004 Texas Instruments. + * + * 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 SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#ifndef _OMAP_WATCHDOG_H +#define _OMAP_WATCHDOG_H + +#define OMAP1610_WATCHDOG_BASE 0xfffeb000 + +#define OMAP_WATCHDOG_BASE OMAP1610_WATCHDOG_BASE + +#define OMAP_WATCHDOG_REV (OMAP_WATCHDOG_BASE + 0x00) +#define OMAP_WATCHDOG_SYS_CONFIG (OMAP_WATCHDOG_BASE + 0x10) +#define OMAP_WATCHDOG_STATUS (OMAP_WATCHDOG_BASE + 0x14) +#define OMAP_WATCHDOG_CNTRL (OMAP_WATCHDOG_BASE + 0x24) +#define OMAP_WATCHDOG_CRR (OMAP_WATCHDOG_BASE + 0x28) +#define OMAP_WATCHDOG_LDR (OMAP_WATCHDOG_BASE + 0x2c) +#define OMAP_WATCHDOG_TGR (OMAP_WATCHDOG_BASE + 0x30) +#define OMAP_WATCHDOG_WPS (OMAP_WATCHDOG_BASE + 0x34) +#define OMAP_WATCHDOG_SPR (OMAP_WATCHDOG_BASE + 0x48) + +#define TIMER_MARGIN_MAX 32 /* Default is 32 seconds */ +#define TIMER_MARGIN_MIN 1 + +#define GET_WLDR_VAL(x) (0xffffffff - ((x) * 32768)) + 1 + +#endif /* _OMAP_WATCHDOG_H */ -- 2.41.1