pcwd_pci.c

linux-2.6.15.6

/*
 *	Berkshire PCI-PC Watchdog Card Driver
 *
 *	(c) Copyright 2003-2005 Wim Van Sebroeck <[e-mail]>.
 *
 *	Based on source code of the following authors:
 *	  Ken Hollis <[e-mail]>,
 *	  Lindsay Harris <[e-mail]>,
 *	  Alan Cox <[e-mail]>,
 *	  Matt Domsch <[e-mail]>,
 *	  Rob Radez <[e-mail]>
 *
 *	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.
 *
 *	Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
 *	provide warranty for any of this software. This material is
 *	provided "AS-IS" and at no charge.
 */

/*
 *	A bells and whistles driver is available from: 
 *	http://www.kernel.org/pub/linux/kernel/people/wim/pcwd/pcwd_pci/
 *
 *	More info available at http://www.berkprod.com/ or http://www.pcwatchdog.com/
 */

/*
 *	Includes, defines, variables, module parameters, ...
 */

#include <linux/config.h>	/* For CONFIG_WATCHDOG_NOWAYOUT/... */
#include <linux/module.h>	/* For module specific items */
#include <linux/moduleparam.h>	/* For new moduleparam's */
#include <linux/types.h>	/* For standard types (like size_t) */
#include <linux/errno.h>	/* For the -ENODEV/... values */
#include <linux/kernel.h>	/* For printk/panic/... */
#include <linux/delay.h>	/* For mdelay function */
#include <linux/miscdevice.h>	/* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
#include <linux/watchdog.h>	/* For the watchdog specific items */
#include <linux/notifier.h>	/* For notifier support */
#include <linux/reboot.h>	/* For reboot_notifier stuff */
#include <linux/init.h>		/* For __init/__exit/... */
#include <linux/fs.h>		/* For file operations */
#include <linux/pci.h>		/* For pci functions */
#include <linux/ioport.h>	/* For io-port access */
#include <linux/spinlock.h>	/* For spin_lock/spin_unlock/... */

#include <asm/uaccess.h>	/* For copy_to_user/put_user/... */
#include <asm/io.h>		/* For inb/outb/... */

/* Module and version information */
#define WATCHDOG_VERSION "1.02"
#define WATCHDOG_DATE "03 Sep 2005"
#define WATCHDOG_DRIVER_NAME "PCI-PC Watchdog"
#define WATCHDOG_NAME "pcwd_pci"
#define PFX WATCHDOG_NAME ": "
#define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION " (" WATCHDOG_DATE ")\n"

/* Stuff for the PCI ID's  */
#ifndef PCI_VENDOR_ID_QUICKLOGIC
#define PCI_VENDOR_ID_QUICKLOGIC    0x11e3
#endif

#ifndef PCI_DEVICE_ID_WATCHDOG_PCIPCWD
#define PCI_DEVICE_ID_WATCHDOG_PCIPCWD 0x5030
#endif

/*
 * These are the defines that describe the control status bits for the
 * PCI-PC Watchdog card.
 */
/* Port 1 : Control Status #1 */
#define WD_PCI_WTRP		0x01	/* Watchdog Trip status */
#define WD_PCI_HRBT		0x02	/* Watchdog Heartbeat */
#define WD_PCI_TTRP		0x04	/* Temperature Trip status */
#define WD_PCI_RL2A		0x08	/* Relay 2 Active */
#define WD_PCI_RL1A		0x10	/* Relay 1 Active */
#define WD_PCI_R2DS		0x40	/* Relay 2 Disable Temperature-trip/reset */
#define WD_PCI_RLY2		0x80	/* Activate Relay 2 on the board */
/* Port 2 : Control Status #2 */
#define WD_PCI_WDIS		0x10	/* Watchdog Disable */
#define WD_PCI_ENTP		0x20	/* Enable Temperature Trip Reset */
#define WD_PCI_WRSP		0x40	/* Watchdog wrote response */
#define WD_PCI_PCMD		0x80	/* PC has sent command */

/* according to documentation max. time to process a command for the pci
 * watchdog card is 100 ms, so we give it 150 ms to do it's job */
#define PCI_COMMAND_TIMEOUT	150

/* Watchdog's internal commands */
#define CMD_GET_STATUS				0x04
#define CMD_GET_FIRMWARE_VERSION		0x08
#define CMD_READ_WATCHDOG_TIMEOUT		0x18
#define CMD_WRITE_WATCHDOG_TIMEOUT		0x19
#define CMD_GET_CLEAR_RESET_COUNT		0x84

/* We can only use 1 card due to the /dev/watchdog restriction */
static int cards_found;

/* internal variables */
static int temp_panic;
static unsigned long is_active;
static char expect_release;
static struct {				/* this is private data for each PCI-PC watchdog card */
	int supports_temp;		/* Wether or not the card has a temperature device */
	int boot_status;		/* The card's boot status */
	unsigned long io_addr;		/* The cards I/O address */
	spinlock_t io_lock;		/* the lock for io operations */
	struct pci_dev *pdev;		/* the PCI-device */
} pcipcwd_private;

/* module parameters */
#define QUIET	0	/* Default */
#define VERBOSE	1	/* Verbose */
#define DEBUG	2	/* print fancy stuff too */
static int debug = QUIET;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)");

#define WATCHDOG_HEARTBEAT 2	/* 2 sec default heartbeat */
static int heartbeat = WATCHDOG_HEARTBEAT;
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");

static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");

/*
 *	Internal functions
 */

static int send_command(int cmd, int *msb, int *lsb)
{
	int got_response, count;

	if (debug >= DEBUG)
		printk(KERN_DEBUG PFX "sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x\n",
		cmd, *msb, *lsb);

	spin_lock(&pcipcwd_private.io_lock);
	/* If a command requires data it should be written first.
	 * Data for commands with 8 bits of data should be written to port 4.
	 * Commands with 16 bits of data, should be written as LSB to port 4
	 * and MSB to port 5.
	 * After the required data has been written then write the command to
	 * port 6. */
	outb_p(*lsb, pcipcwd_private.io_addr + 4);
	outb_p(*msb, pcipcwd_private.io_addr + 5);
	outb_p(cmd, pcipcwd_private.io_addr + 6);

	/* wait till the pci card processed the command, signaled by
	 * the WRSP bit in port 2 and give it a max. timeout of
	 * PCI_COMMAND_TIMEOUT to process */
	got_response = inb_p(pcipcwd_private.io_addr + 2) & WD_PCI_WRSP;
	for (count = 0; (count < PCI_COMMAND_TIMEOUT) && (!got_response); count++) {
		mdelay(1);
		got_response = inb_p(pcipcwd_private.io_addr + 2) & WD_PCI_WRSP;
	}

	if (debug >= DEBUG) {
		if (got_response) {
			printk(KERN_DEBUG PFX "time to process command was: %d ms\n",
				count);
		} else {
			printk(KERN_DEBUG PFX "card did not respond on command!\n");
		}
	}

	if (got_response) {
		/* read back response */
		*lsb = inb_p(pcipcwd_private.io_addr + 4);
		*msb = inb_p(pcipcwd_private.io_addr + 5);

		/* clear WRSP bit */
		inb_p(pcipcwd_private.io_addr + 6);

		if (debug >= DEBUG)
			printk(KERN_DEBUG PFX "received following data for cmd=0x%02x: msb=0x%02x lsb=0x%02x\n",
				cmd, *msb, *lsb);
	}

	spin_unlock(&pcipcwd_private.io_lock);

	return got_response;
}

static inline void pcipcwd_check_temperature_support(void)
{
	if (inb_p(pcipcwd_private.io_addr) != 0xF0)
		pcipcwd_private.supports_temp = 1;
}

static int pcipcwd_get_option_switches(void)
{
	int option_switches;

	option_switches = inb_p(pcipcwd_private.io_addr + 3);
	return option_switches;
}

static void pcipcwd_show_card_info(void)
{
	int got_fw_rev, fw_rev_major, fw_rev_minor;
	char fw_ver_str[20];		/* The cards firmware version */
	int option_switches;

	got_fw_rev = send_command(CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
	if (got_fw_rev) {
		sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
	} else {
		sprintf(fw_ver_str, "<card no answer>");
	}

	/* Get switch settings */
	option_switches = pcipcwd_get_option_switches();

	printk(KERN_INFO PFX "Found card at port 0x%04x (Firmware: %s) %s temp option\n",
		(int) pcipcwd_private.io_addr, fw_ver_str,
		(pcipcwd_private.supports_temp ? "with" : "without"));

	printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
		option_switches,
		((option_switches & 0x10) ? "ON" : "OFF"),
		((option_switches & 0x08) ? "ON" : "OFF"));

	if (pcipcwd_private.boot_status & WDIOF_CARDRESET)
		printk(KERN_INFO PFX "Previous reset was caused by the Watchdog card\n");

	if (pcipcwd_private.boot_status & WDIOF_OVERHEAT)
		printk(KERN_INFO PFX "Card sensed a CPU Overheat\n");

	if (pcipcwd_private.boot_status == 0)
		printk(KERN_INFO PFX "No previous trip detected - Cold boot or reset\n");
}

static int pcipcwd_start(void)
{
	int stat_reg;

	spin_lock(&pcipcwd_private.io_lock);
	outb_p(0x00, pcipcwd_private.io_addr + 3);
	udelay(1000);

	stat_reg = inb_p(pcipcwd_private.io_addr + 2);
	spin_unlock(&pcipcwd_private.io_lock);

	if (stat_reg & WD_PCI_WDIS) {
		printk(KERN_ERR PFX "Card timer not enabled\n");
		return -1;
	}

	if (debug >= VERBOSE)
		printk(KERN_DEBUG PFX "Watchdog started\n");

	return 0;
}

static int pcipcwd_stop(void)
{
	int stat_reg;

	spin_lock(&pcipcwd_private.io_lock);
	outb_p(0xA5, pcipcwd_private.io_addr + 3);
	udelay(1000);

	outb_p(0xA5, pcipcwd_private.io_addr + 3);
	udelay(1000);

	stat_reg = inb_p(pcipcwd_private.io_addr + 2);
	spin_unlock(&pcipcwd_private.io_lock);

	if (!(stat_reg & WD_PCI_WDIS)) {
		printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
		return -1;
	}

	if (debug >= VERBOSE)
		printk(KERN_DEBUG PFX "Watchdog stopped\n");

	return 0;
}

static int pcipcwd_keepalive(void)
{
	/* Re-trigger watchdog by writing to port 0 */
	outb_p(0x42, pcipcwd_private.io_addr);	/* send out any data */

	if (debug >= DEBUG)
		printk(KERN_DEBUG PFX "Watchdog keepalive signal send\n");

	return 0;
}

static int pcipcwd_set_heartbeat(int t)
{
	int t_msb = t / 256;
	int t_lsb = t % 256;

	if ((t < 0x0001) || (t > 0xFFFF))
		return -EINVAL;

	/* Write new heartbeat to watchdog */
	send_command(CMD_WRITE_WATCHDOG_TIMEOUT, &t_msb, &t_lsb);

	heartbeat = t;
	if (debug >= VERBOSE)
		printk(KERN_DEBUG PFX "New heartbeat: %d\n",
		       heartbeat);

	return 0;
}

static int pcipcwd_get_status(int *status)
{
	int control_status;

	*status=0;
	control_status = inb_p(pcipcwd_private.io_addr + 1);
	if (control_status & WD_PCI_WTRP)
		*status |= WDIOF_CARDRESET;
	if (control_status & WD_PCI_TTRP) {
		*status |= WDIOF_OVERHEAT;
		if (temp_panic)
			panic(PFX "Temperature overheat trip!\n");
	}

	if (debug >= DEBUG)
		printk(KERN_DEBUG PFX "Control Status #1: 0x%02x\n",
		       control_status);

	return 0;
}

static int pcipcwd_clear_status(void)
{
	int control_status;
	int msb;
	int reset_counter;

	if (debug >= VERBOSE)
		printk(KERN_INFO PFX "clearing watchdog trip status & LED\n");

	control_status = inb_p(pcipcwd_private.io_addr + 1);

	if (debug >= DEBUG) {
		printk(KERN_DEBUG PFX "status was: 0x%02x\n", control_status);
		printk(KERN_DEBUG PFX "sending: 0x%02x\n",
		       (control_status & WD_PCI_R2DS) | WD_PCI_WTRP);
	}

	/* clear trip status & LED and keep mode of relay 2 */
	outb_p((control_status & WD_PCI_R2DS) | WD_PCI_WTRP, pcipcwd_private.io_addr + 1);

	/* clear reset counter */
	msb=0;
	reset_counter=0xff;
	send_command(CMD_GET_CLEAR_RESET_COUNT, &msb, &reset_counter);

	if (debug >= DEBUG) {
		printk(KERN_DEBUG PFX "reset count was: 0x%02x\n",
		       reset_counter);
	}

	return 0;
}

static int pcipcwd_get_temperature(int *temperature)
{
	*temperature = 0;
	if (!pcipcwd_private.supports_temp)
		return -ENODEV;

	*temperature = inb_p(pcipcwd_private.io_addr);

	/*
	 * Convert celsius to fahrenheit, since this was
	 * the decided 'standard' for this return value.
	 */
	*temperature = (*temperature * 9 / 5) + 32;

	if (debug >= DEBUG) {
		printk(KERN_DEBUG PFX "temperature is: %d F\n",
		       *temperature);
	}

	return 0;
}