[net-next-2.6.git] / drivers / firmware / dcdbas.c

/*
 *  dcdbas.c: Dell Systems Management Base Driver
 *
 *  The Dell Systems Management Base Driver provides a sysfs interface for
 *  systems management software to perform System Management Interrupts (SMIs)
 *  and Host Control Actions (power cycle or power off after OS shutdown) on
 *  Dell systems.
 *
 *  See Documentation/dcdbas.txt for more information.
 *
 *  Copyright (C) 1995-2006 Dell Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License v2.0 as published by
 *  the Free Software Foundation.
 *
 *  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.
 */

#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mc146818rtc.h>
#include <linux/module.h>
#include <linux/reboot.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <asm/io.h>

#include "dcdbas.h"

#define DRIVER_NAME		"dcdbas"
#define DRIVER_VERSION		"5.6.0-3.2"
#define DRIVER_DESCRIPTION	"Dell Systems Management Base Driver"

static struct platform_device *dcdbas_pdev;

static u8 *smi_data_buf;
static dma_addr_t smi_data_buf_handle;
static unsigned long smi_data_buf_size;
static u32 smi_data_buf_phys_addr;
static DEFINE_MUTEX(smi_data_lock);

static unsigned int host_control_action;
static unsigned int host_control_smi_type;
static unsigned int host_control_on_shutdown;

/**
 * smi_data_buf_free: free SMI data buffer
 */
static void smi_data_buf_free(void)
{
	if (!smi_data_buf)
		return;

	dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
		__func__, smi_data_buf_phys_addr, smi_data_buf_size);

	dma_free_coherent(&dcdbas_pdev->dev, smi_data_buf_size, smi_data_buf,
			  smi_data_buf_handle);
	smi_data_buf = NULL;
	smi_data_buf_handle = 0;
	smi_data_buf_phys_addr = 0;
	smi_data_buf_size = 0;
}

/**
 * smi_data_buf_realloc: grow SMI data buffer if needed
 */
static int smi_data_buf_realloc(unsigned long size)
{
	void *buf;
	dma_addr_t handle;

	if (smi_data_buf_size >= size)
		return 0;

	if (size > MAX_SMI_DATA_BUF_SIZE)
		return -EINVAL;

	/* new buffer is needed */
	buf = dma_alloc_coherent(&dcdbas_pdev->dev, size, &handle, GFP_KERNEL);
	if (!buf) {
		dev_dbg(&dcdbas_pdev->dev,
			"%s: failed to allocate memory size %lu\n",
			__func__, size);
		return -ENOMEM;
	}
	/* memory zeroed by dma_alloc_coherent */

	if (smi_data_buf)
		memcpy(buf, smi_data_buf, smi_data_buf_size);

	/* free any existing buffer */
	smi_data_buf_free();

	/* set up new buffer for use */
	smi_data_buf = buf;
	smi_data_buf_handle = handle;
	smi_data_buf_phys_addr = (u32) virt_to_phys(buf);
	smi_data_buf_size = size;

	dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
		__func__, smi_data_buf_phys_addr, smi_data_buf_size);

	return 0;
}

static ssize_t smi_data_buf_phys_addr_show(struct device *dev,
					   struct device_attribute *attr,
					   char *buf)
{
	return sprintf(buf, "%x\n", smi_data_buf_phys_addr);
}

static ssize_t smi_data_buf_size_show(struct device *dev,
				      struct device_attribute *attr,
				      char *buf)
{
	return sprintf(buf, "%lu\n", smi_data_buf_size);
}

static ssize_t smi_data_buf_size_store(struct device *dev,
				       struct device_attribute *attr,
				       const char *buf, size_t count)
{
	unsigned long buf_size;
	ssize_t ret;

	buf_size = simple_strtoul(buf, NULL, 10);

	/* make sure SMI data buffer is at least buf_size */
	mutex_lock(&smi_data_lock);
	ret = smi_data_buf_realloc(buf_size);
	mutex_unlock(&smi_data_lock);
	if (ret)
		return ret;

	return count;
}

static ssize_t smi_data_read(struct kobject *kobj,
			     struct bin_attribute *bin_attr,
			     char *buf, loff_t pos, size_t count)
{
	ssize_t ret;

	mutex_lock(&smi_data_lock);
	ret = memory_read_from_buffer(buf, count, &pos, smi_data_buf,
					smi_data_buf_size);
	mutex_unlock(&smi_data_lock);
	return ret;
}

static ssize_t smi_data_write(struct kobject *kobj,
			      struct bin_attribute *bin_attr,
			      char *buf, loff_t pos, size_t count)
{
	ssize_t ret;

	if ((pos + count) > MAX_SMI_DATA_BUF_SIZE)
		return -EINVAL;

	mutex_lock(&smi_data_lock);

	ret = smi_data_buf_realloc(pos + count);
	if (ret)
		goto out;

	memcpy(smi_data_buf + pos, buf, count);
	ret = count;
out:
	mutex_unlock(&smi_data_lock);
	return ret;
}

static ssize_t host_control_action_show(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	return sprintf(buf, "%u\n", host_control_action);
}

static ssize_t host_control_action_store(struct device *dev,
					 struct device_attribute *attr,
					 const char *buf, size_t count)
{
	ssize_t ret;

	/* make sure buffer is available for host control command */
	mutex_lock(&smi_data_lock);
	ret = smi_data_buf_realloc(sizeof(struct apm_cmd));
	mutex_unlock(&smi_data_lock);
	if (ret)
		return ret;

	host_control_action = simple_strtoul(buf, NULL, 10);
	return count;
}

static ssize_t host_control_smi_type_show(struct device *dev,
					  struct device_attribute *attr,
					  char *buf)
{
	return sprintf(buf, "%u\n", host_control_smi_type);
}

static ssize_t host_control_smi_type_store(struct device *dev,
					   struct device_attribute *attr,
					   const char *buf, size_t count)
{
	host_control_smi_type = simple_strtoul(buf, NULL, 10);
	return count;
}

static ssize_t host_control_on_shutdown_show(struct device *dev,
					     struct device_attribute *attr,
					     char *buf)
{
	return sprintf(buf, "%u\n", host_control_on_shutdown);
}

static ssize_t host_control_on_shutdown_store(struct device *dev,
					      struct device_attribute *attr,
					      const char *buf, size_t count)
{
	host_control_on_shutdown = simple_strtoul(buf, NULL, 10);
	return count;
}

/**
 * dcdbas_smi_request: generate SMI request
 *
 * Called with smi_data_lock.
 */
int dcdbas_smi_request(struct smi_cmd *smi_cmd)
{
	cpumask_var_t old_mask;
	int ret = 0;

	if (smi_cmd->magic != SMI_CMD_MAGIC) {
		dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
			 __func__);
		return -EBADR;
	}

	/* SMI requires CPU 0 */
	if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
		return -ENOMEM;

	cpumask_copy(old_mask, &current->cpus_allowed);
	set_cpus_allowed_ptr(current, cpumask_of(0));
	if (smp_processor_id() != 0) {
		dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n",
			__func__);
		ret = -EBUSY;
		goto out;
	}

	/* generate SMI */
	asm volatile (
		"outb %b0,%w1"
		: /* no output args */
		: "a" (smi_cmd->command_code),
		  "d" (smi_cmd->command_address),
		  "b" (smi_cmd->ebx),
		  "c" (smi_cmd->ecx)
		: "memory"
	);

out:
	set_cpus_allowed_ptr(current, old_mask);
	free_cpumask_var(old_mask);
	return ret;
}

/**
 * smi_request_store:
 *
 * The valid values are:
 * 0: zero SMI data buffer
 * 1: generate calling interface SMI
 * 2: generate raw SMI
 *
 * User application writes smi_cmd to smi_data before telling driver
 * to generate SMI.
 */
static ssize_t smi_request_store(struct device *dev,
				 struct device_attribute *attr,
				 const char *buf, size_t count)
{
	struct smi_cmd *smi_cmd;
	unsigned long val = simple_strtoul(buf, NULL, 10);
	ssize_t ret;

	mutex_lock(&smi_data_lock);

	if (smi_data_buf_size < sizeof(struct smi_cmd)) {
		ret = -ENODEV;
		goto out;
	}
	smi_cmd = (struct smi_cmd *)smi_data_buf;

	switch (val) {
	case 2:
		/* Raw SMI */
		ret = dcdbas_smi_request(smi_cmd);
		if (!ret)
			ret = count;
		break;
	case 1:
		/* Calling Interface SMI */
		smi_cmd->ebx = (u32) virt_to_phys(smi_cmd->command_buffer);
		ret = dcdbas_smi_request(smi_cmd);
		if (!ret)
			ret = count;
		break;
	case 0:
		memset(smi_data_buf, 0, smi_data_buf_size);
		ret = count;
		break;
	default:
		ret = -EINVAL;
		break;
	}

out:
	mutex_unlock(&smi_data_lock);
	return ret;
}
EXPORT_SYMBOL(dcdbas_smi_request);

/**
 * host_control_smi: generate host control SMI
 *
 * Caller must set up the host control command in smi_data_buf.
 */
static int host_control_smi(void)
{
	struct apm_cmd *apm_cmd;
	u8 *data;
	unsigned long flags;
	u32 num_ticks;
	s8 cmd_status;
	u8 index;

	apm_cmd = (struct apm_cmd *)smi_data_buf;
	apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL;

	switch (host_control_smi_type) {
	case HC_SMITYPE_TYPE1:
		spin_lock_irqsave(&rtc_lock, flags);
		/* write SMI data buffer physical address */
		data = (u8 *)&smi_data_buf_phys_addr;
		for (index = PE1300_CMOS_CMD_STRUCT_PTR;
		     index < (PE1300_CMOS_CMD_STRUCT_PTR + 4);
		     index++, data++) {
			outb(index,
			     (CMOS_BASE_PORT + CMOS_PAGE2_INDEX_PORT_PIIX4));
			outb(*data,
			     (CMOS_BASE_PORT + CMOS_PAGE2_DATA_PORT_PIIX4));
		}

		/* first set status to -1 as called by spec */
		cmd_status = ESM_STATUS_CMD_UNSUCCESSFUL;
		outb((u8) cmd_status, PCAT_APM_STATUS_PORT);

		/* generate SMM call */
		outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
		spin_unlock_irqrestore(&rtc_lock, flags);

		/* wait a few to see if it executed */
		num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
		while ((cmd_status = inb(PCAT_APM_STATUS_PORT))
		       == ESM_STATUS_CMD_UNSUCCESSFUL) {
			num_ticks--;
			if (num_ticks == EXPIRED_TIMER)
				return -ETIME;
		}
		break;

	case HC_SMITYPE_TYPE2:
	case HC_SMITYPE_TYPE3:
		spin_lock_irqsave(&rtc_lock, flags);
		/* write SMI data buffer physical address */
		data = (u8 *)&smi_data_buf_phys_addr;
		for (index = PE1400_CMOS_CMD_STRUCT_PTR;
		     index < (PE1400_CMOS_CMD_STRUCT_PTR + 4);
		     index++, data++) {
			outb(index, (CMOS_BASE_PORT + CMOS_PAGE1_INDEX_PORT));
			outb(*data, (CMOS_BASE_PORT + CMOS_PAGE1_DATA_PORT));
		}

		/* generate SMM call */
		if (host_control_smi_type == HC_SMITYPE_TYPE3)
			outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
		else
			outb(ESM_APM_CMD, PE1400_APM_CONTROL_PORT);

		/* restore RTC index pointer since it was written to above */
		CMOS_READ(RTC_REG_C);
		spin_unlock_irqrestore(&rtc_lock, flags);

		/* read control port back to serialize write */
		cmd_status = inb(PE1400_APM_CONTROL_PORT);

		/* wait a few to see if it executed */
		num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
		while (apm_cmd->status == ESM_STATUS_CMD_UNSUCCESSFUL) {
			num_ticks--;
			if (num_ticks == EXPIRED_TIMER)
				return -ETIME;
		}
		break;

	default:
		dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n",
			__func__, host_control_smi_type);
		return -ENOSYS;
	}

	return 0;
}

/**
 * dcdbas_host_control: initiate host control
 *
 * This function is called by the driver after the system has
 * finished shutting down if the user application specified a
 * host control action to perform on shutdown.  It is safe to
 * use smi_data_buf at this point because the system has finished
 * shutting down and no userspace apps are running.
 */
static void dcdbas_host_control(void)
{
	struct apm_cmd *apm_cmd;
	u8 action;

	if (host_control_action == HC_ACTION_NONE)
		return;

	action = host_control_action;
	host_control_action = HC_ACTION_NONE;

	if (!smi_data_buf) {
		dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__);
		return;
	}

	if (smi_data_buf_size < sizeof(struct apm_cmd)) {
		dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n",
			__func__);
		return;
	}

	apm_cmd = (struct apm_cmd *)smi_data_buf;

	/* power off takes precedence */
	if (action & HC_ACTION_HOST_CONTROL_POWEROFF) {
		apm_cmd->command = ESM_APM_POWER_CYCLE;
		apm_cmd->reserved = 0;
		*((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 0;
		host_control_smi();
	} else if (action & HC_ACTION_HOST_CONTROL_POWERCYCLE) {
		apm_cmd->command = ESM_APM_POWER_CYCLE;
		apm_cmd->reserved = 0;
		*((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 20;
		host_control_smi();
	}
}

/**
 * dcdbas_reboot_notify: handle reboot notification for host control
 */
static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code,
				void *unused)
{
	switch (code) {
	case SYS_DOWN:
	case SYS_HALT:
	case SYS_POWER_OFF:
		if (host_control_on_shutdown) {
			/* firmware is going to perform host control action */
			printk(KERN_WARNING "Please wait for shutdown "
			       "action to complete...\n");
			dcdbas_host_control();
		}
		break;
	}

	return NOTIFY_DONE;
}

static struct notifier_block dcdbas_reboot_nb = {
	.notifier_call = dcdbas_reboot_notify,
	.next = NULL,
	.priority = INT_MIN
};

static DCDBAS_BIN_ATTR_RW(smi_data);

static struct bin_attribute *dcdbas_bin_attrs[] = {
	&bin_attr_smi_data,
	NULL
};

static DCDBAS_DEV_ATTR_RW(smi_data_buf_size);
static DCDBAS_DEV_ATTR_RO(smi_data_buf_phys_addr);
static DCDBAS_DEV_ATTR_WO(smi_request);
static DCDBAS_DEV_ATTR_RW(host_control_action);
static DCDBAS_DEV_ATTR_RW(host_control_smi_type);
static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown);

static struct attribute *dcdbas_dev_attrs[] = {
	&dev_attr_smi_data_buf_size.attr,
	&dev_attr_smi_data_buf_phys_addr.attr,
	&dev_attr_smi_request.attr,
	&dev_attr_host_control_action.attr,
	&dev_attr_host_control_smi_type.attr,
	&dev_attr_host_control_on_shutdown.attr,
	NULL
};

static struct attribute_group dcdbas_attr_group = {
	.attrs = dcdbas_dev_attrs,
};

static int __devinit dcdbas_probe(struct platform_device *dev)
{
	int i, error;

	host_control_action = HC_ACTION_NONE;
	host_control_smi_type = HC_SMITYPE_NONE;

	/*
	 * BIOS SMI calls require buffer addresses be in 32-bit address space.
	 * This is done by setting the DMA mask below.
	 */
	dcdbas_pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
	dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask;

	error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
	if (error)
		return error;

	for (i = 0; dcdbas_bin_attrs[i]; i++) {
		error = sysfs_create_bin_file(&dev->dev.kobj,
					      dcdbas_bin_attrs[i]);
		if (error) {
			while (--i >= 0)
				sysfs_remove_bin_file(&dev->dev.kobj,
						      dcdbas_bin_attrs[i]);
			sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);
			return error;
		}
	}

	register_reboot_notifier(&dcdbas_reboot_nb);

	dev_info(&dev->dev, "%s (version %s)\n",
		 DRIVER_DESCRIPTION, DRIVER_VERSION);

	return 0;
}

static int __devexit dcdbas_remove(struct platform_device *dev)
{
	int i;

	unregister_reboot_notifier(&dcdbas_reboot_nb);
	for (i = 0; dcdbas_bin_attrs[i]; i++)
		sysfs_remove_bin_file(&dev->dev.kobj, dcdbas_bin_attrs[i]);
	sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);

	return 0;
}

static struct platform_driver dcdbas_driver = {
	.driver		= {
		.name	= DRIVER_NAME,
		.owner	= THIS_MODULE,
	},
	.probe		= dcdbas_probe,
	.remove		= __devexit_p(dcdbas_remove),
};

/**
 * dcdbas_init: initialize driver
 */
static int __init dcdbas_init(void)
{
	int error;

	error = platform_driver_register(&dcdbas_driver);
	if (error)
		return error;

	dcdbas_pdev = platform_device_alloc(DRIVER_NAME, -1);
	if (!dcdbas_pdev) {
		error = -ENOMEM;
		goto err_unregister_driver;
	}

	error = platform_device_add(dcdbas_pdev);
	if (error)
		goto err_free_device;

	return 0;

 err_free_device:
	platform_device_put(dcdbas_pdev);
 err_unregister_driver:
	platform_driver_unregister(&dcdbas_driver);
	return error;
}

/**
 * dcdbas_exit: perform driver cleanup
 */
static void __exit dcdbas_exit(void)
{
	/*
	 * make sure functions that use dcdbas_pdev are called
	 * before platform_device_unregister
	 */
	unregister_reboot_notifier(&dcdbas_reboot_nb);
	smi_data_buf_free();
	platform_device_unregister(dcdbas_pdev);
	platform_driver_unregister(&dcdbas_driver);

	/*
	 * We have to free the buffer here instead of dcdbas_remove
	 * because only in module exit function we can be sure that
	 * all sysfs attributes belonging to this module have been
	 * released.
	 */
	smi_data_buf_free();
}

module_init(dcdbas_init);
module_exit(dcdbas_exit);

MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")");
MODULE_VERSION(DRIVER_VERSION);
MODULE_AUTHOR("Dell Inc.");
MODULE_LICENSE("GPL");
/* Any System or BIOS claiming to be by Dell */
MODULE_ALIAS("dmi:*:[bs]vnD[Ee][Ll][Ll]*:*");
Commit	Line	Data
90563ec4 DW	1	/*
	2	* dcdbas.c: Dell Systems Management Base Driver
	3	*
	4	* The Dell Systems Management Base Driver provides a sysfs interface for
	5	* systems management software to perform System Management Interrupts (SMIs)
	6	* and Host Control Actions (power cycle or power off after OS shutdown) on
	7	* Dell systems.
	8	*
	9	* See Documentation/dcdbas.txt for more information.
	10	*
b95936cb	11	* Copyright (C) 1995-2006 Dell Inc.
90563ec4 DW	12	*
	13	* This program is free software; you can redistribute it and/or modify
	14	* it under the terms of the GNU General Public License v2.0 as published by
	15	* the Free Software Foundation.
	16	*
	17	* This program is distributed in the hope that it will be useful,
	18	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	* GNU General Public License for more details.
	21	*/
	22
d052d1be	23	#include <linux/platform_device.h>
90563ec4 DW	24	#include <linux/dma-mapping.h>
	25	#include <linux/errno.h>
	26	#include <linux/init.h>
	27	#include <linux/kernel.h>
	28	#include <linux/mc146818rtc.h>
	29	#include <linux/module.h>
	30	#include <linux/reboot.h>
	31	#include <linux/sched.h>
	32	#include <linux/smp.h>
	33	#include <linux/spinlock.h>
	34	#include <linux/string.h>
	35	#include <linux/types.h>
8ed965d6	36	#include <linux/mutex.h>
90563ec4	37	#include <asm/io.h>
90563ec4 DW	38
	39	#include "dcdbas.h"
	40
	41	#define DRIVER_NAME "dcdbas"
b95936cb	42	#define DRIVER_VERSION "5.6.0-3.2"
90563ec4 DW	43	#define DRIVER_DESCRIPTION "Dell Systems Management Base Driver"
	44
	45	static struct platform_device *dcdbas_pdev;
	46
	47	static u8 *smi_data_buf;
	48	static dma_addr_t smi_data_buf_handle;
	49	static unsigned long smi_data_buf_size;
	50	static u32 smi_data_buf_phys_addr;
8ed965d6	51	static DEFINE_MUTEX(smi_data_lock);
90563ec4 DW	52
	53	static unsigned int host_control_action;
	54	static unsigned int host_control_smi_type;
	55	static unsigned int host_control_on_shutdown;
	56
	57	/**
	58	* smi_data_buf_free: free SMI data buffer
	59	*/
	60	static void smi_data_buf_free(void)
	61	{
	62	if (!smi_data_buf)
	63	return;
	64
	65	dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
eecd5853	66	__func__, smi_data_buf_phys_addr, smi_data_buf_size);
90563ec4 DW	67
	68	dma_free_coherent(&dcdbas_pdev->dev, smi_data_buf_size, smi_data_buf,
	69	smi_data_buf_handle);
	70	smi_data_buf = NULL;
	71	smi_data_buf_handle = 0;
	72	smi_data_buf_phys_addr = 0;
	73	smi_data_buf_size = 0;
	74	}
	75
	76	/**
	77	* smi_data_buf_realloc: grow SMI data buffer if needed
	78	*/
	79	static int smi_data_buf_realloc(unsigned long size)
	80	{
	81	void *buf;
	82	dma_addr_t handle;
	83
	84	if (smi_data_buf_size >= size)
	85	return 0;
	86
	87	if (size > MAX_SMI_DATA_BUF_SIZE)
	88	return -EINVAL;
	89
	90	/* new buffer is needed */
	91	buf = dma_alloc_coherent(&dcdbas_pdev->dev, size, &handle, GFP_KERNEL);
	92	if (!buf) {
	93	dev_dbg(&dcdbas_pdev->dev,
	94	"%s: failed to allocate memory size %lu\n",
eecd5853	95	__func__, size);
90563ec4 DW	96	return -ENOMEM;
	97	}
	98	/* memory zeroed by dma_alloc_coherent */
	99
	100	if (smi_data_buf)
	101	memcpy(buf, smi_data_buf, smi_data_buf_size);
	102
	103	/* free any existing buffer */
	104	smi_data_buf_free();
	105
	106	/* set up new buffer for use */
	107	smi_data_buf = buf;
	108	smi_data_buf_handle = handle;
	109	smi_data_buf_phys_addr = (u32) virt_to_phys(buf);
	110	smi_data_buf_size = size;
	111
	112	dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
eecd5853	113	__func__, smi_data_buf_phys_addr, smi_data_buf_size);
90563ec4 DW	114
	115	return 0;
	116	}
	117
	118	static ssize_t smi_data_buf_phys_addr_show(struct device *dev,
	119	struct device_attribute *attr,
	120	char *buf)
	121	{
	122	return sprintf(buf, "%x\n", smi_data_buf_phys_addr);
	123	}
	124
	125	static ssize_t smi_data_buf_size_show(struct device *dev,
	126	struct device_attribute *attr,
	127	char *buf)
	128	{
	129	return sprintf(buf, "%lu\n", smi_data_buf_size);
	130	}
	131
	132	static ssize_t smi_data_buf_size_store(struct device *dev,
	133	struct device_attribute *attr,
	134	const char *buf, size_t count)
	135	{
	136	unsigned long buf_size;
	137	ssize_t ret;
	138
	139	buf_size = simple_strtoul(buf, NULL, 10);
	140
	141	/* make sure SMI data buffer is at least buf_size */
8ed965d6	142	mutex_lock(&smi_data_lock);
90563ec4	143	ret = smi_data_buf_realloc(buf_size);
8ed965d6	144	mutex_unlock(&smi_data_lock);
90563ec4 DW	145	if (ret)
	146	return ret;
	147
	148	return count;
	149	}
	150
91a69029 ZR	151	static ssize_t smi_data_read(struct kobject *kobj,
	152	struct bin_attribute *bin_attr,
	153	char *buf, loff_t pos, size_t count)
90563ec4	154	{
90563ec4 DW	155	ssize_t ret;
90563ec4 DW	156
8ed965d6	157	mutex_lock(&smi_data_lock);
abe19b7b AM	158	ret = memory_read_from_buffer(buf, count, &pos, smi_data_buf,
abe19b7b AM	159	smi_data_buf_size);
8ed965d6	160	mutex_unlock(&smi_data_lock);
90563ec4 DW	161	return ret;
	162	}
	163
91a69029 ZR	164	static ssize_t smi_data_write(struct kobject *kobj,
	165	struct bin_attribute *bin_attr,
	166	char *buf, loff_t pos, size_t count)
90563ec4 DW	167	{
	168	ssize_t ret;
	169
b95936cb DW	170	if ((pos + count) > MAX_SMI_DATA_BUF_SIZE)
	171	return -EINVAL;
	172
8ed965d6	173	mutex_lock(&smi_data_lock);
90563ec4 DW	174
	175	ret = smi_data_buf_realloc(pos + count);
	176	if (ret)
	177	goto out;
	178
	179	memcpy(smi_data_buf + pos, buf, count);
	180	ret = count;
	181	out:
8ed965d6	182	mutex_unlock(&smi_data_lock);
90563ec4 DW	183	return ret;
	184	}
	185
	186	static ssize_t host_control_action_show(struct device *dev,
	187	struct device_attribute *attr,
	188	char *buf)
	189	{
	190	return sprintf(buf, "%u\n", host_control_action);
	191	}
	192
	193	static ssize_t host_control_action_store(struct device *dev,
	194	struct device_attribute *attr,
	195	const char *buf, size_t count)
	196	{
	197	ssize_t ret;
	198
	199	/* make sure buffer is available for host control command */
8ed965d6	200	mutex_lock(&smi_data_lock);
90563ec4	201	ret = smi_data_buf_realloc(sizeof(struct apm_cmd));
8ed965d6	202	mutex_unlock(&smi_data_lock);
90563ec4 DW	203	if (ret)
	204	return ret;
	205
	206	host_control_action = simple_strtoul(buf, NULL, 10);
	207	return count;
	208	}
	209
	210	static ssize_t host_control_smi_type_show(struct device *dev,
	211	struct device_attribute *attr,
	212	char *buf)
	213	{
	214	return sprintf(buf, "%u\n", host_control_smi_type);
	215	}
	216
	217	static ssize_t host_control_smi_type_store(struct device *dev,
	218	struct device_attribute *attr,
	219	const char *buf, size_t count)
	220	{
	221	host_control_smi_type = simple_strtoul(buf, NULL, 10);
	222	return count;
	223	}
	224
	225	static ssize_t host_control_on_shutdown_show(struct device *dev,
	226	struct device_attribute *attr,
	227	char *buf)
	228	{
	229	return sprintf(buf, "%u\n", host_control_on_shutdown);
	230	}
	231
	232	static ssize_t host_control_on_shutdown_store(struct device *dev,
	233	struct device_attribute *attr,
	234	const char *buf, size_t count)
	235	{
	236	host_control_on_shutdown = simple_strtoul(buf, NULL, 10);
	237	return count;
	238	}
	239
	240	/**
3cab7fd9	241	* dcdbas_smi_request: generate SMI request
90563ec4 DW	242	*
	243	* Called with smi_data_lock.
	244	*/
3cab7fd9	245	int dcdbas_smi_request(struct smi_cmd *smi_cmd)
90563ec4	246	{
c90e785b	247	cpumask_var_t old_mask;
90563ec4 DW	248	int ret = 0;
	249
	250	if (smi_cmd->magic != SMI_CMD_MAGIC) {
	251	dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
eecd5853	252	__func__);
90563ec4 DW	253	return -EBADR;
	254	}
	255
	256	/* SMI requires CPU 0 */
c90e785b MT	257	if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
	258	return -ENOMEM;
	259
	260	cpumask_copy(old_mask, &current->cpus_allowed);
	261	set_cpus_allowed_ptr(current, cpumask_of(0));
90563ec4 DW	262	if (smp_processor_id() != 0) {
90563ec4 DW	263	dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n",
eecd5853	264	__func__);
90563ec4 DW	265	ret = -EBUSY;
	266	goto out;
	267	}
	268
	269	/* generate SMI */
	270	asm volatile (
	271	"outb %b0,%w1"
	272	: /* no output args */
	273	: "a" (smi_cmd->command_code),
	274	"d" (smi_cmd->command_address),
	275	"b" (smi_cmd->ebx),
	276	"c" (smi_cmd->ecx)
	277	: "memory"
	278	);
	279
	280	out:
c90e785b MT	281	set_cpus_allowed_ptr(current, old_mask);
c90e785b MT	282	free_cpumask_var(old_mask);
90563ec4 DW	283	return ret;
	284	}
	285
	286	/**
	287	* smi_request_store:
	288	*
	289	* The valid values are:
	290	* 0: zero SMI data buffer
	291	* 1: generate calling interface SMI
	292	* 2: generate raw SMI
	293	*
	294	* User application writes smi_cmd to smi_data before telling driver
	295	* to generate SMI.
	296	*/
	297	static ssize_t smi_request_store(struct device *dev,
	298	struct device_attribute *attr,
	299	const char *buf, size_t count)
	300	{
	301	struct smi_cmd *smi_cmd;
	302	unsigned long val = simple_strtoul(buf, NULL, 10);
	303	ssize_t ret;
	304
8ed965d6	305	mutex_lock(&smi_data_lock);
90563ec4 DW	306
	307	if (smi_data_buf_size < sizeof(struct smi_cmd)) {
	308	ret = -ENODEV;
	309	goto out;
	310	}
	311	smi_cmd = (struct smi_cmd *)smi_data_buf;
	312
	313	switch (val) {
	314	case 2:
	315	/* Raw SMI */
3cab7fd9	316	ret = dcdbas_smi_request(smi_cmd);
90563ec4 DW	317	if (!ret)
	318	ret = count;
	319	break;
	320	case 1:
	321	/* Calling Interface SMI */
	322	smi_cmd->ebx = (u32) virt_to_phys(smi_cmd->command_buffer);
3cab7fd9	323	ret = dcdbas_smi_request(smi_cmd);
90563ec4 DW	324	if (!ret)
	325	ret = count;
	326	break;
	327	case 0:
	328	memset(smi_data_buf, 0, smi_data_buf_size);
	329	ret = count;
	330	break;
	331	default:
	332	ret = -EINVAL;
	333	break;
	334	}
	335
	336	out:
8ed965d6	337	mutex_unlock(&smi_data_lock);
90563ec4 DW	338	return ret;
90563ec4 DW	339	}
3cab7fd9	340	EXPORT_SYMBOL(dcdbas_smi_request);
90563ec4 DW	341
	342	/**
	343	* host_control_smi: generate host control SMI
	344	*
	345	* Caller must set up the host control command in smi_data_buf.
	346	*/
	347	static int host_control_smi(void)
	348	{
	349	struct apm_cmd *apm_cmd;
	350	u8 *data;
	351	unsigned long flags;
	352	u32 num_ticks;
	353	s8 cmd_status;
	354	u8 index;
	355
	356	apm_cmd = (struct apm_cmd *)smi_data_buf;
	357	apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL;
	358
	359	switch (host_control_smi_type) {
	360	case HC_SMITYPE_TYPE1:
	361	spin_lock_irqsave(&rtc_lock, flags);
	362	/* write SMI data buffer physical address */
	363	data = (u8 *)&smi_data_buf_phys_addr;
	364	for (index = PE1300_CMOS_CMD_STRUCT_PTR;
	365	index < (PE1300_CMOS_CMD_STRUCT_PTR + 4);
	366	index++, data++) {
	367	outb(index,
	368	(CMOS_BASE_PORT + CMOS_PAGE2_INDEX_PORT_PIIX4));
	369	outb(*data,
	370	(CMOS_BASE_PORT + CMOS_PAGE2_DATA_PORT_PIIX4));
	371	}
	372
	373	/* first set status to -1 as called by spec */
	374	cmd_status = ESM_STATUS_CMD_UNSUCCESSFUL;
	375	outb((u8) cmd_status, PCAT_APM_STATUS_PORT);
	376
	377	/* generate SMM call */
	378	outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
	379	spin_unlock_irqrestore(&rtc_lock, flags);
	380
	381	/* wait a few to see if it executed */
	382	num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
	383	while ((cmd_status = inb(PCAT_APM_STATUS_PORT))
	384	== ESM_STATUS_CMD_UNSUCCESSFUL) {
	385	num_ticks--;
	386	if (num_ticks == EXPIRED_TIMER)
	387	return -ETIME;
	388	}
	389	break;
	390
	391	case HC_SMITYPE_TYPE2:
	392	case HC_SMITYPE_TYPE3:
	393	spin_lock_irqsave(&rtc_lock, flags);
	394	/* write SMI data buffer physical address */
	395	data = (u8 *)&smi_data_buf_phys_addr;
	396	for (index = PE1400_CMOS_CMD_STRUCT_PTR;
	397	index < (PE1400_CMOS_CMD_STRUCT_PTR + 4);
	398	index++, data++) {
	399	outb(index, (CMOS_BASE_PORT + CMOS_PAGE1_INDEX_PORT));
	400	outb(*data, (CMOS_BASE_PORT + CMOS_PAGE1_DATA_PORT));
	401	}
	402
	403	/* generate SMM call */
	404	if (host_control_smi_type == HC_SMITYPE_TYPE3)
405	outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
406	else
407	outb(ESM_APM_CMD, PE1400_APM_CONTROL_PORT);
408
409	/* restore RTC index pointer since it was written to above */
410	CMOS_READ(RTC_REG_C);
411	spin_unlock_irqrestore(&rtc_lock, flags);
412
413	/* read control port back to serialize write */
414	cmd_status = inb(PE1400_APM_CONTROL_PORT);
415
416	/* wait a few to see if it executed */
417	num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
418	while (apm_cmd->status == ESM_STATUS_CMD_UNSUCCESSFUL) {
419	num_ticks--;
420	if (num_ticks == EXPIRED_TIMER)
421	return -ETIME;
422	}
423	break;
424
425	default:
426	dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n",
eecd5853	427	__func__, host_control_smi_type);
90563ec4 DW	428	return -ENOSYS;
	429	}
	430
	431	return 0;
	432	}
	433
	434	/**
	435	* dcdbas_host_control: initiate host control
	436	*
	437	* This function is called by the driver after the system has
	438	* finished shutting down if the user application specified a
	439	* host control action to perform on shutdown. It is safe to
	440	* use smi_data_buf at this point because the system has finished
	441	* shutting down and no userspace apps are running.
	442	*/
	443	static void dcdbas_host_control(void)
	444	{
	445	struct apm_cmd *apm_cmd;
	446	u8 action;
	447
	448	if (host_control_action == HC_ACTION_NONE)
	449	return;
	450
	451	action = host_control_action;
	452	host_control_action = HC_ACTION_NONE;
	453
	454	if (!smi_data_buf) {
eecd5853	455	dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__);
90563ec4 DW	456	return;
	457	}
	458
	459	if (smi_data_buf_size < sizeof(struct apm_cmd)) {
	460	dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n",
eecd5853	461	__func__);
90563ec4 DW	462	return;
	463	}
	464
	465	apm_cmd = (struct apm_cmd *)smi_data_buf;
	466
	467	/* power off takes precedence */
	468	if (action & HC_ACTION_HOST_CONTROL_POWEROFF) {
	469	apm_cmd->command = ESM_APM_POWER_CYCLE;
	470	apm_cmd->reserved = 0;
	471	((s16 )&apm_cmd->parameters.shortreq.parm[0]) = (s16) 0;
	472	host_control_smi();
	473	} else if (action & HC_ACTION_HOST_CONTROL_POWERCYCLE) {
	474	apm_cmd->command = ESM_APM_POWER_CYCLE;
	475	apm_cmd->reserved = 0;
	476	((s16 )&apm_cmd->parameters.shortreq.parm[0]) = (s16) 20;
	477	host_control_smi();
	478	}
	479	}
	480
	481	/**
	482	* dcdbas_reboot_notify: handle reboot notification for host control
	483	*/
	484	static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code,
	485	void *unused)
	486	{
90563ec4 DW	487	switch (code) {
	488	case SYS_DOWN:
	489	case SYS_HALT:
	490	case SYS_POWER_OFF:
	491	if (host_control_on_shutdown) {
	492	/* firmware is going to perform host control action */
e041c683 AS	493	printk(KERN_WARNING "Please wait for shutdown "
	494	"action to complete...\n");
	495	dcdbas_host_control();
90563ec4 DW	496	}
	497	break;
	498	}
	499
	500	return NOTIFY_DONE;
	501	}
	502
	503	static struct notifier_block dcdbas_reboot_nb = {
	504	.notifier_call = dcdbas_reboot_notify,
	505	.next = NULL,
e041c683	506	.priority = INT_MIN
90563ec4 DW	507	};
	508
	509	static DCDBAS_BIN_ATTR_RW(smi_data);
	510
	511	static struct bin_attribute *dcdbas_bin_attrs[] = {
	512	&bin_attr_smi_data,
	513	NULL
	514	};
	515
	516	static DCDBAS_DEV_ATTR_RW(smi_data_buf_size);
	517	static DCDBAS_DEV_ATTR_RO(smi_data_buf_phys_addr);
	518	static DCDBAS_DEV_ATTR_WO(smi_request);
	519	static DCDBAS_DEV_ATTR_RW(host_control_action);
	520	static DCDBAS_DEV_ATTR_RW(host_control_smi_type);
	521	static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown);
	522
a7f3ea72 DT	523	static struct attribute *dcdbas_dev_attrs[] = {
	524	&dev_attr_smi_data_buf_size.attr,
	525	&dev_attr_smi_data_buf_phys_addr.attr,
	526	&dev_attr_smi_request.attr,
	527	&dev_attr_host_control_action.attr,
	528	&dev_attr_host_control_smi_type.attr,
	529	&dev_attr_host_control_on_shutdown.attr,
90563ec4 DW	530	NULL
	531	};
	532
a7f3ea72 DT	533	static struct attribute_group dcdbas_attr_group = {
	534	.attrs = dcdbas_dev_attrs,
	535	};
	536
	537	static int __devinit dcdbas_probe(struct platform_device *dev)
90563ec4	538	{
a7f3ea72	539	int i, error;
90563ec4 DW	540
	541	host_control_action = HC_ACTION_NONE;
	542	host_control_smi_type = HC_SMITYPE_NONE;
	543
90563ec4 DW	544	/*
	545	* BIOS SMI calls require buffer addresses be in 32-bit address space.
	546	* This is done by setting the DMA mask below.
	547	*/
284901a9	548	dcdbas_pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
90563ec4 DW	549	dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask;
90563ec4 DW	550
a7f3ea72 DT	551	error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
	552	if (error)
	553	return error;
	554
	555	for (i = 0; dcdbas_bin_attrs[i]; i++) {
	556	error = sysfs_create_bin_file(&dev->dev.kobj,
	557	dcdbas_bin_attrs[i]);
	558	if (error) {
	559	while (--i >= 0)
	560	sysfs_remove_bin_file(&dev->dev.kobj,
	561	dcdbas_bin_attrs[i]);
0968cf51	562	sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);
a7f3ea72 DT	563	return error;
	564	}
	565	}
	566
90563ec4 DW	567	register_reboot_notifier(&dcdbas_reboot_nb);
90563ec4 DW	568
a7f3ea72 DT	569	dev_info(&dev->dev, "%s (version %s)\n",
	570	DRIVER_DESCRIPTION, DRIVER_VERSION);
	571
	572	return 0;
	573	}
	574
	575	static int __devexit dcdbas_remove(struct platform_device *dev)
	576	{
	577	int i;
	578
	579	unregister_reboot_notifier(&dcdbas_reboot_nb);
90563ec4	580	for (i = 0; dcdbas_bin_attrs[i]; i++)
a7f3ea72 DT	581	sysfs_remove_bin_file(&dev->dev.kobj, dcdbas_bin_attrs[i]);
a7f3ea72 DT	582	sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);
90563ec4	583
a7f3ea72 DT	584	return 0;
a7f3ea72 DT	585	}
90563ec4	586
a7f3ea72 DT	587	static struct platform_driver dcdbas_driver = {
	588	.driver = {
	589	.name = DRIVER_NAME,
	590	.owner = THIS_MODULE,
	591	},
	592	.probe = dcdbas_probe,
	593	.remove = __devexit_p(dcdbas_remove),
	594	};
	595
	596	/**
	597	* dcdbas_init: initialize driver
	598	*/
	599	static int __init dcdbas_init(void)
	600	{
	601	int error;
	602
	603	error = platform_driver_register(&dcdbas_driver);
	604	if (error)
	605	return error;
	606
	607	dcdbas_pdev = platform_device_alloc(DRIVER_NAME, -1);
	608	if (!dcdbas_pdev) {
	609	error = -ENOMEM;
	610	goto err_unregister_driver;
	611	}
	612
	613	error = platform_device_add(dcdbas_pdev);
	614	if (error)
	615	goto err_free_device;
90563ec4 DW	616
90563ec4 DW	617	return 0;
a7f3ea72 DT	618
	619	err_free_device:
	620	platform_device_put(dcdbas_pdev);
	621	err_unregister_driver:
	622	platform_driver_unregister(&dcdbas_driver);
	623	return error;
90563ec4 DW	624	}
	625
	626	/**
	627	* dcdbas_exit: perform driver cleanup
	628	*/
	629	static void __exit dcdbas_exit(void)
	630	{
435a80f6 DW	631	/*
	632	* make sure functions that use dcdbas_pdev are called
	633	* before platform_device_unregister
	634	*/
90563ec4 DW	635	unregister_reboot_notifier(&dcdbas_reboot_nb);
90563ec4 DW	636	smi_data_buf_free();
435a80f6	637	platform_device_unregister(dcdbas_pdev);
a7f3ea72 DT	638	platform_driver_unregister(&dcdbas_driver);
	639
	640	/*
	641	* We have to free the buffer here instead of dcdbas_remove
	642	* because only in module exit function we can be sure that
	643	* all sysfs attributes belonging to this module have been
	644	* released.
	645	*/
	646	smi_data_buf_free();
90563ec4 DW	647	}
	648
	649	module_init(dcdbas_init);
	650	module_exit(dcdbas_exit);
	651
	652	MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")");
	653	MODULE_VERSION(DRIVER_VERSION);
	654	MODULE_AUTHOR("Dell Inc.");
	655	MODULE_LICENSE("GPL");
8f47f0b6 MD	656	/* Any System or BIOS claiming to be by Dell */
8f47f0b6 MD	657	MODULE_ALIAS("dmi::[bs]vnD[Ee][Ll][Ll]:*");