Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753457AbYAURvL (ORCPT ); Mon, 21 Jan 2008 12:51:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751558AbYAURu4 (ORCPT ); Mon, 21 Jan 2008 12:50:56 -0500 Received: from outbound-dub.frontbridge.com ([213.199.154.16]:13603 "EHLO outbound7-dub-R.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751668AbYAURuy (ORCPT ); Mon, 21 Jan 2008 12:50:54 -0500 X-Greylist: delayed 2503 seconds by postgrey-1.27 at vger.kernel.org; Mon, 21 Jan 2008 12:50:54 EST X-BigFish: VP X-MS-Exchange-Organization-Antispam-Report: OrigIP: 163.181.251.8;Service: EHS X-Server-Uuid: DF9F24A0-1A5C-40A5-8B0A-DEB676E72ECF Date: Mon, 21 Jan 2008 10:07:00 -0700 From: "Jordan Crouse" To: "Arnd Hannemann" cc: "Andres Salomon" , marc.jones@amd.com, "Linux Kernel Mailing List" , wim@iguana.be Subject: Re: Geode GX/LX watchdog timer (RESEND) Message-ID: <20080121170700.GC6884@cosmic.amd.com> References: <20080116165606.3ebc06a4@ephemeral> <478F25D6.3060503@i4.informatik.rwth-aachen.de> <20080117134032.4cc1a1cf@ephemeral> <478FB255.5040001@i4.informatik.rwth-aachen.de> <20080117211917.GF8244@cosmic.amd.com> <478FCDB6.4010708@i4.informatik.rwth-aachen.de> <20080117223644.GK8244@cosmic.amd.com> <478FDC12.6020505@i4.informatik.rwth-aachen.de> <20080119010624.GA25328@cosmic.amd.com> <47934B2E.3020707@i4.informatik.rwth-aachen.de> MIME-Version: 1.0 In-Reply-To: <47934B2E.3020707@i4.informatik.rwth-aachen.de> User-Agent: Mutt/1.5.15+20070412 (2007-04-11) X-OriginalArrivalTime: 21 Jan 2008 17:05:52.0589 (UTC) FILETIME=[E0ED77D0:01C85C4F] X-WSS-ID: 6B8A0F7B07S8666279-01-01 Content-Type: multipart/mixed; boundary="jI8keyz6grp/JLjh" Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12289 Lines: 456 --jI8keyz6grp/JLjh Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 20/01/08 14:22 +0100, Arnd Hannemann wrote: > Hi, >=20 > Jordan Crouse wrote: > > On 17/01/08 23:52 +0100, Arnd Hannemann wrote: > >>>> Watchdog for the new API would be great :-) > >>> Coming soon. > >=20 > > As promised, a watchdog driver for the Geode GX/LX processors is attach= ed. > > I basically just ported the previous patch forward to 2.6.24. >=20 > Great work! >=20 > >=20 > > I also have good news or bad news depending on your perspective. I wan= ted > > to test this against 2.6.24, and OLPC is stuck at an older kernel versi= on, > > so I had to test this with coreboot (LinuxBIOS) on another Geode=20 > > platform. Like all BIOSen execpt for the OLPC firmware, coreboot uses > > VSA (SMM handler) which consumes all the timers. > >=20 > > So I used the magical MSR and surprise! - the timer tick hung. =20 > > I compiled out the timer tick, and tested the watchdog timer instead, > > and it worked fine on timer 0. So I don't think the MFGPTs themselves > > have anything to do with this problem, but I do think it might be=20 > > related to VSA and possibly interrupts too. I'm going to invoke the > > strong BIOS fu of our LinuxBIOS / BIOS expert Marc Jones, and see what > > he comes up with. > >=20 > > I don't know how much of a hassle it would be for Andres to get a 2.6.24 > > kernel running on the OLPC to make sure that this isn't a regression > > in the timer tick code (I suspect it isn't a regression, but you never > > know). I also think that it would probably be in our best interest to > > default CONFIG_GEODE_MFGPT_TIMER to 'n' until we get this figured > > out. Since most BIOSen don't have timers available, that shouldn't aff= ect > > too many people. > >=20 > > So, anyway, enjoy the watchdog timer - I hope it meets everybody's > > expectations for the 2.6.25 kernel. >=20 > Thanks a lot for this, it works great! (with CONFIG_GEODE_MFGPT_TIMER > not set). > However some minor issues: > Could the name of the /dev entry perhaps be changed from > "geode-watchdog" to "watchdog" instead? > I think all other watchdogs use "watchdog", and using two different > watchdogs in the same machine won't work anyway, because of the same > minor number, right? >=20 > As a second point my gcc (4.1.2) issues a warning: >=20 > drivers/watchdog/geodewdt.c: In function =E2=80=98geodewdt_remove=E2=80= =99: > drivers/watchdog/geodewdt.c:256: warning: control reaches end of > non-void function >=20 > which I think is a valid one. Resending with Arnd's concern's addressed. Thanks. =20 Jordan --jI8keyz6grp/JLjh Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename=geode-watchdog.patch Content-Transfer-Encoding: 7bit [GEODE] Add a watchdog driver based on the CS5535/CS5536 MFGPT timers From: Jordan Crouse Add a watchdog timer based on the MFGPT timers in the CS5535/CS5536 companion chips to the AMD Geode GX and LX processors. Only caveat is that the BIOS must provide at least a one free timer, and most do not. Signed-off-by: Jordan Crouse --- drivers/watchdog/Kconfig | 13 ++ drivers/watchdog/Makefile | 1 drivers/watchdog/geodewdt.c | 309 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 323 insertions(+), 0 deletions(-) diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 52dff40..15b4c29 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -295,6 +295,19 @@ config ALIM7101_WDT Most people will say N. +config GEODE_WDT + tristate "AMD Geode CS5535/CS5536 Watchdog" + depends on MGEODE_LX + help + This driver enables a watchdog capability built into the + CS5535/CS5536 companion chips for the AMD Geode GX and LX + processors. This watchdog watches your kernel to make sure + it doesn't freeze, and if it does, it reboots your computer after + a certain amount of time. + + You can compile this driver directly into the kernel, or use + it as a module. The module will be called geodewdt. + config SC520_WDT tristate "AMD Elan SC520 processor Watchdog" depends on X86 diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 87483cc..830ce70 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -59,6 +59,7 @@ obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o obj-$(CONFIG_ADVANTECH_WDT) += advantechwdt.o obj-$(CONFIG_ALIM1535_WDT) += alim1535_wdt.o obj-$(CONFIG_ALIM7101_WDT) += alim7101_wdt.o +obj-$(CONFIG_GEODE_WDT) += geodewdt.o obj-$(CONFIG_SC520_WDT) += sc520_wdt.o obj-$(CONFIG_EUROTECH_WDT) += eurotechwdt.o obj-$(CONFIG_IB700_WDT) += ib700wdt.o diff --git a/drivers/watchdog/geodewdt.c b/drivers/watchdog/geodewdt.c new file mode 100644 index 0000000..f85b196 --- /dev/null +++ b/drivers/watchdog/geodewdt.c @@ -0,0 +1,309 @@ +/* Watchdog timer for the Geode GX/LX with the CS5535/CS5536 companion chip + * + * Copyright (C) 2006-2007, Advanced Micro Devices, Inc. + * + * 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 + +#define GEODEWDT_HZ 500 +#define GEODEWDT_SCALE 6 +#define GEODEWDT_MAX_SECONDS 131 + +#define WDT_FLAGS_OPEN 1 +#define WDT_FLAGS_ORPHAN 2 + +#define DRV_NAME "geodewdt" +#define WATCHDOG_NAME "Geode GX/LX WDT" +#define WATCHDOG_TIMEOUT 60 + +static int timeout = WATCHDOG_TIMEOUT; +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=131, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); + +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static struct platform_device *geodewdt_platform_device; +static unsigned long wdt_flags; +static int wdt_timer; +static int safe_close; + +static void geodewdt_ping(void) +{ + /* Stop the counter */ + geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0); + + /* Reset the counter */ + geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0); + + /* Enable the counter */ + geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, MFGPT_SETUP_CNTEN); +} + +static void geodewdt_disable(void) +{ + geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0); + geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0); +} + +static int geodewdt_set_heartbeat(int val) +{ + if (val < 1 || val > GEODEWDT_MAX_SECONDS) + return -EINVAL; + + geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, 0); + geode_mfgpt_write(wdt_timer, MFGPT_REG_CMP2, val * GEODEWDT_HZ); + geode_mfgpt_write(wdt_timer, MFGPT_REG_COUNTER, 0); + geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, MFGPT_SETUP_CNTEN); + + timeout = val; + return 0; +} + +static int +geodewdt_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(WDT_FLAGS_OPEN, &wdt_flags)) + return -EBUSY; + + if (!test_and_clear_bit(WDT_FLAGS_ORPHAN, &wdt_flags)) + __module_get(THIS_MODULE); + + geodewdt_ping(); + return nonseekable_open(inode, file); +} + +static int +geodewdt_release(struct inode *inode, struct file *file) +{ + if (safe_close) { + geodewdt_disable(); + module_put(THIS_MODULE); + } + else { + printk(KERN_CRIT "Unexpected close - watchdog is not stopping.\n"); + geodewdt_ping(); + + set_bit(WDT_FLAGS_ORPHAN, &wdt_flags); + } + + clear_bit(WDT_FLAGS_OPEN, &wdt_flags); + safe_close = 0; + return 0; +} + +static ssize_t +geodewdt_write(struct file *file, const char __user *data, size_t len, + loff_t *ppos) +{ + if(len) { + if (!nowayout) { + size_t i; + safe_close = 0; + + for (i = 0; i != len; i++) { + char c; + + if (get_user(c, data + i)) + return -EFAULT; + + if (c == 'V') + safe_close = 1; + } + } + + geodewdt_ping(); + } + return len; +} + +static int +geodewdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, + unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int __user *p = argp; + int interval; + + static struct watchdog_info ident = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING + | WDIOF_MAGICCLOSE, + .firmware_version = 1, + .identity = WATCHDOG_NAME, + }; + + switch(cmd) { + case WDIOC_GETSUPPORT: + return copy_to_user(argp, &ident, + sizeof(ident)) ? -EFAULT : 0; + break; + + case WDIOC_GETSTATUS: + case WDIOC_GETBOOTSTATUS: + return put_user(0, p); + + case WDIOC_KEEPALIVE: + geodewdt_ping(); + return 0; + + case WDIOC_SETTIMEOUT: + if (get_user(interval, p)) + return -EFAULT; + + if (geodewdt_set_heartbeat(interval)) + return -EINVAL; + +/* Fall through */ + + case WDIOC_GETTIMEOUT: + return put_user(timeout, p); + + case WDIOC_SETOPTIONS: + { + int options, ret = -EINVAL; + + if (get_user(options, p)) + return -EFAULT; + + if (options & WDIOS_DISABLECARD) { + geodewdt_disable(); + ret = 0; + } + + if (options & WDIOS_ENABLECARD) { + geodewdt_ping(); + ret = 0; + } + + return ret; + } + default: + return -ENOTTY; + } + + return 0; +} + +static const struct file_operations geodewdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = geodewdt_write, + .ioctl = geodewdt_ioctl, + .open = geodewdt_open, + .release = geodewdt_release, +}; + +static struct miscdevice geodewdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &geodewdt_fops +}; + +static int __devinit +geodewdt_probe(struct platform_device *dev) +{ + int ret, timer; + + timer = geode_mfgpt_alloc_timer(MFGPT_TIMER_ANY, + MFGPT_DOMAIN_WORKING, THIS_MODULE); + + if (timer == -1) { + printk(KERN_ERR "geodewdt: No timers were available\n"); + return -ENODEV; + } + + wdt_timer = timer; + + /* Set up the timer */ + + geode_mfgpt_write(wdt_timer, MFGPT_REG_SETUP, + GEODEWDT_SCALE | (3 << 8)); + + /* Set up comparator 2 to reset when the event fires */ + geode_mfgpt_toggle_event(wdt_timer, MFGPT_CMP2, MFGPT_EVENT_RESET, 1); + + /* Set up the initial timeout */ + + geode_mfgpt_write(wdt_timer, MFGPT_REG_CMP2, + timeout * GEODEWDT_HZ); + + ret = misc_register(&geodewdt_miscdev); + + return ret; +} + +static int __devexit +geodewdt_remove(struct platform_device *dev) +{ + misc_deregister(&geodewdt_miscdev); + return 0; +} + +static void +geodewdt_shutdown(struct platform_device *dev) +{ + geodewdt_disable(); +} + +static struct platform_driver geodewdt_driver = { + .probe = geodewdt_probe, + .remove = __devexit_p(geodewdt_remove), + .shutdown = geodewdt_shutdown, + .driver = { + .owner = THIS_MODULE, + .name = DRV_NAME, + }, +}; + +static int __init +geodewdt_init(void) +{ + int ret; + + ret = platform_driver_register(&geodewdt_driver); + if (ret) + return ret; + + geodewdt_platform_device = platform_device_register_simple(DRV_NAME, -1, NULL, 0); + if (IS_ERR(geodewdt_platform_device)) { + ret = PTR_ERR(geodewdt_platform_device); + goto err; + } + + return 0; +err: + platform_driver_unregister(&geodewdt_driver); + return ret; +} + +static void __exit +geodewdt_exit(void) +{ + platform_device_unregister(geodewdt_platform_device); + platform_driver_unregister(&geodewdt_driver); +} + +module_init(geodewdt_init); +module_exit(geodewdt_exit); + +MODULE_AUTHOR("Advanced Micro Devices, Inc"); +MODULE_DESCRIPTION("Geode GX/LX Watchdog Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); --jI8keyz6grp/JLjh-- -- 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/