Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423038AbWAMW1t (ORCPT ); Fri, 13 Jan 2006 17:27:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423034AbWAMW1s (ORCPT ); Fri, 13 Jan 2006 17:27:48 -0500 Received: from gate.crashing.org ([63.228.1.57]:29578 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S1423035AbWAMW1r (ORCPT ); Fri, 13 Jan 2006 17:27:47 -0500 Date: Fri, 13 Jan 2006 16:18:58 -0600 (CST) From: Kumar Gala To: wim@iguana.be, Andrew Morton cc: linux-kernel@vger.kernel.org, , , , Paul Mackerras Subject: [PATCH] powerpc: Add support for the MPC83xx watchdog Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8163 Lines: 289 Added support for the PowerPC MPC83xx watchdog. The MPC83xx has a simple watchdog that once enabled it can not be stopped, has some simple timeout range selection, and the ability to either reset the processor or take a machine check. Signed-off-by: Dave Updegraff Signed-off-by: Kumar Gala --- commit 829b5a27d84d8ea95f6ba7314702c11127b5102c tree 1eb3a840aea5ff2de729e510458d24688e4da59e parent ae97a598202f4076627acaba0fcc1884f0c703d7 author Kumar Gala Fri, 13 Jan 2006 16:22:58 -0600 committer Kumar Gala Fri, 13 Jan 2006 16:22:58 -0600 drivers/char/watchdog/Kconfig | 4 + drivers/char/watchdog/Makefile | 1 drivers/char/watchdog/mpc83xx_wdt.c | 230 +++++++++++++++++++++++++++++++++++ 3 files changed, 235 insertions(+), 0 deletions(-) diff --git a/drivers/char/watchdog/Kconfig b/drivers/char/watchdog/Kconfig index a654479..32c035b 100644 --- a/drivers/char/watchdog/Kconfig +++ b/drivers/char/watchdog/Kconfig @@ -401,6 +401,10 @@ config 8xx_WDT tristate "MPC8xx Watchdog Timer" depends on WATCHDOG && 8xx +config 83xx_WDT + tristate "MPC83xx Watchdog Timer" + depends on WATCHDOG && PPC_83xx + config MV64X60_WDT tristate "MV64X60 (Marvell Discovery) Watchdog Timer" depends on WATCHDOG && MV64X60 diff --git a/drivers/char/watchdog/Makefile b/drivers/char/watchdog/Makefile index cfd0a39..4342b0d 100644 --- a/drivers/char/watchdog/Makefile +++ b/drivers/char/watchdog/Makefile @@ -55,6 +55,7 @@ obj-$(CONFIG_MACHZ_WDT) += machzwd.o # PowerPC Architecture obj-$(CONFIG_8xx_WDT) += mpc8xx_wdt.o +obj-$(CONFIG_83xx_WDT) += mpc83xx_wdt.o obj-$(CONFIG_MV64X60_WDT) += mv64x60_wdt.o obj-$(CONFIG_BOOKE_WDT) += booke_wdt.o diff --git a/drivers/char/watchdog/mpc83xx_wdt.c b/drivers/char/watchdog/mpc83xx_wdt.c new file mode 100644 index 0000000..5734839 --- /dev/null +++ b/drivers/char/watchdog/mpc83xx_wdt.c @@ -0,0 +1,230 @@ +/* + * mpc83xx_wdt.c - MPC83xx watchdog userspace interface + * + * Authors: Dave Updegraff + * Kumar Gala + * Attribution: from 83xx_wst: Florian Schirmer + * ..and from sc520_wdt + * + * Note: it appears that you can only actually ENABLE or DISABLE the thing + * once after POR. Once enabled, you cannot disable, and vice versa. + * + * 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. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct mpc83xx_wdt { + __be32 res0; + __be32 swcrr; /* System watchdog control register */ +#define SWCRR_SWTC 0xFFFF0000 /* Software Watchdog Time Count. */ +#define SWCRR_SWEN 0x00000004 /* Watchdog Enable bit. */ +#define SWCRR_SWRI 0x00000002 /* Software Watchdog Reset/Interrupt Select bit.*/ +#define SWCRR_SWPR 0x00000001 /* Software Watchdog Counter Prescale bit. */ + __be32 swcnr; /* System watchdog count register */ + u8 res1[2]; + __be16 swsrr; /* System watchdog service register */ + u8 res2[0xF0]; +}; + +static struct mpc83xx_wdt __iomem *wd_base; + +static ushort timeout = 0xffff; +module_param(timeout, ushort, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in ticks. (0swsrr, 0x556c); + out_be16(&wd_base->swsrr, 0xaa39); + spin_unlock(&wdt_spinlock); +} + +static ssize_t mpc83xx_wdt_write(struct file * file, const char __user * buf, + size_t count, loff_t * ppos) +{ + if(count) + mpc83xx_wdt_keepalive(); + return count; +} + +static int mpc83xx_wdt_open(struct inode * inode, struct file * file) +{ + u32 tmp = SWCRR_SWEN; + if (test_and_set_bit(0, &wdt_is_open)) + return -EBUSY; + + /* Once we start the watchdog we can't stop it */ + __module_get(THIS_MODULE); + + /* Good, fire up the show */ + if (prescale) + tmp |= SWCRR_SWPR; + if (reset) + tmp |= SWCRR_SWRI; + + tmp |= timeout << 16; + + out_be32(&wd_base->swcrr, tmp); + + return nonseekable_open(inode, file); +} + +static int mpc83xx_wdt_release(struct inode * inode, struct file * file) +{ + printk(KERN_CRIT "Unexpected close, not stopping watchdog!\n"); + mpc83xx_wdt_keepalive(); + clear_bit(0, &wdt_is_open); + return 0; +} + +static int mpc83xx_wdt_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, + unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int __user *p = argp; + static struct watchdog_info ident = { + .options = WDIOF_KEEPALIVEPING, + .firmware_version = 1, + .identity = "MPC83xx", + }; + + switch(cmd) + { + case WDIOC_GETSUPPORT: + return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0; + case WDIOC_KEEPALIVE: + mpc83xx_wdt_keepalive(); + return 0; + case WDIOC_GETTIMEOUT: + return put_user(timeout_sec, p); + + default: + return -ENOIOCTLCMD; + } +} + +static struct file_operations mpc83xx_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = mpc83xx_wdt_write, + .ioctl = mpc83xx_wdt_ioctl, + .open = mpc83xx_wdt_open, + .release = mpc83xx_wdt_release, +}; + +static struct miscdevice mpc83xx_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &mpc83xx_wdt_fops, +}; + +static int __devinit mpc83xx_wdt_probe(struct platform_device *dev) +{ + struct resource *r; + int ret; + unsigned int *freq = dev->dev.platform_data; + + /* get a pointer to the register memory */ + r = platform_get_resource(dev, IORESOURCE_MEM, 0); + + if (!r) { + ret = -ENODEV; + goto err_out; + } + + wd_base = (struct mpc83xx_wdt *) + ioremap(r->start, sizeof (struct mpc83xx_wdt)); + + if (wd_base == NULL) { + ret = -ENOMEM; + goto err_out; + } + + ret = misc_register(&mpc83xx_wdt_miscdev); + if (ret) { + printk(KERN_ERR "cannot register miscdev on minor=%d (err=%d)\n", + WATCHDOG_MINOR, ret); + goto err_unmap; + } + + /* Calculate the timeout in seconds */ + if (prescale) + timeout_sec = (timeout * 0x10000) / (*freq); + else + timeout_sec = timeout / (*freq); + + printk(KERN_INFO "WDT driver for MPC83xx initialized. " + "mode:%s timeout=%d (%d seconds)\n", + reset ? "reset":"interrupt", timeout, timeout_sec); + + spin_lock_init(&wdt_spinlock); + + return 0; + +err_unmap: + iounmap(wd_base); +err_out: + return ret; +} + +static int __devexit mpc83xx_wdt_remove(struct platform_device *dev) +{ + misc_deregister(&mpc83xx_wdt_miscdev); + iounmap(wd_base); + + return 0; +} + +static struct platform_driver mpc83xx_wdt_driver = { + .probe = mpc83xx_wdt_probe, + .remove = __devexit_p(mpc83xx_wdt_remove), + .driver = { + .owner = THIS_MODULE, + .name = "mpc83xx_wdt", + }, +}; + +static int __init mpc83xx_wdt_init(void) +{ + return platform_driver_register(&mpc83xx_wdt_driver); +} + +static void __exit mpc83xx_wdt_exit(void) +{ + platform_driver_unregister(&mpc83xx_wdt_driver); +} + +module_init(mpc83xx_wdt_init); +module_exit(mpc83xx_wdt_exit); + +MODULE_AUTHOR("Dave Updegraff, Kumar Gala"); +MODULE_DESCRIPTION("Driver for watchdog timer in MPC83xx uProcessor"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/