2 * dcdbas.c: Dell Systems Management Base Driver
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
9 * See Documentation/dcdbas.txt for more information.
11 * Copyright (C) 1995-2006 Dell Inc.
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.
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.
23 #include <linux/platform_device.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/errno.h>
26 #include <linux/gfp.h>
27 #include <linux/init.h>
28 #include <linux/kernel.h>
29 #include <linux/mc146818rtc.h>
30 #include <linux/module.h>
31 #include <linux/reboot.h>
32 #include <linux/sched.h>
33 #include <linux/smp.h>
34 #include <linux/spinlock.h>
35 #include <linux/string.h>
36 #include <linux/types.h>
37 #include <linux/mutex.h>
42 #define DRIVER_NAME "dcdbas"
43 #define DRIVER_VERSION "5.6.0-3.2"
44 #define DRIVER_DESCRIPTION "Dell Systems Management Base Driver"
46 static struct platform_device *dcdbas_pdev;
48 static u8 *smi_data_buf;
49 static dma_addr_t smi_data_buf_handle;
50 static unsigned long smi_data_buf_size;
51 static u32 smi_data_buf_phys_addr;
52 static DEFINE_MUTEX(smi_data_lock);
54 static unsigned int host_control_action;
55 static unsigned int host_control_smi_type;
56 static unsigned int host_control_on_shutdown;
59 * smi_data_buf_free: free SMI data buffer
61 static void smi_data_buf_free(void)
66 dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
67 __func__, smi_data_buf_phys_addr, smi_data_buf_size);
69 dma_free_coherent(&dcdbas_pdev->dev, smi_data_buf_size, smi_data_buf,
72 smi_data_buf_handle = 0;
73 smi_data_buf_phys_addr = 0;
74 smi_data_buf_size = 0;
78 * smi_data_buf_realloc: grow SMI data buffer if needed
80 static int smi_data_buf_realloc(unsigned long size)
85 if (smi_data_buf_size >= size)
88 if (size > MAX_SMI_DATA_BUF_SIZE)
91 /* new buffer is needed */
92 buf = dma_alloc_coherent(&dcdbas_pdev->dev, size, &handle, GFP_KERNEL);
94 dev_dbg(&dcdbas_pdev->dev,
95 "%s: failed to allocate memory size %lu\n",
99 /* memory zeroed by dma_alloc_coherent */
102 memcpy(buf, smi_data_buf, smi_data_buf_size);
104 /* free any existing buffer */
107 /* set up new buffer for use */
109 smi_data_buf_handle = handle;
110 smi_data_buf_phys_addr = (u32) virt_to_phys(buf);
111 smi_data_buf_size = size;
113 dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
114 __func__, smi_data_buf_phys_addr, smi_data_buf_size);
119 static ssize_t smi_data_buf_phys_addr_show(struct device *dev,
120 struct device_attribute *attr,
123 return sprintf(buf, "%x\n", smi_data_buf_phys_addr);
126 static ssize_t smi_data_buf_size_show(struct device *dev,
127 struct device_attribute *attr,
130 return sprintf(buf, "%lu\n", smi_data_buf_size);
133 static ssize_t smi_data_buf_size_store(struct device *dev,
134 struct device_attribute *attr,
135 const char *buf, size_t count)
137 unsigned long buf_size;
140 buf_size = simple_strtoul(buf, NULL, 10);
142 /* make sure SMI data buffer is at least buf_size */
143 mutex_lock(&smi_data_lock);
144 ret = smi_data_buf_realloc(buf_size);
145 mutex_unlock(&smi_data_lock);
152 static ssize_t smi_data_read(struct file *filp, struct kobject *kobj,
153 struct bin_attribute *bin_attr,
154 char *buf, loff_t pos, size_t count)
158 mutex_lock(&smi_data_lock);
159 ret = memory_read_from_buffer(buf, count, &pos, smi_data_buf,
161 mutex_unlock(&smi_data_lock);
165 static ssize_t smi_data_write(struct file *filp, struct kobject *kobj,
166 struct bin_attribute *bin_attr,
167 char *buf, loff_t pos, size_t count)
171 if ((pos + count) > MAX_SMI_DATA_BUF_SIZE)
174 mutex_lock(&smi_data_lock);
176 ret = smi_data_buf_realloc(pos + count);
180 memcpy(smi_data_buf + pos, buf, count);
183 mutex_unlock(&smi_data_lock);
187 static ssize_t host_control_action_show(struct device *dev,
188 struct device_attribute *attr,
191 return sprintf(buf, "%u\n", host_control_action);
194 static ssize_t host_control_action_store(struct device *dev,
195 struct device_attribute *attr,
196 const char *buf, size_t count)
200 /* make sure buffer is available for host control command */
201 mutex_lock(&smi_data_lock);
202 ret = smi_data_buf_realloc(sizeof(struct apm_cmd));
203 mutex_unlock(&smi_data_lock);
207 host_control_action = simple_strtoul(buf, NULL, 10);
211 static ssize_t host_control_smi_type_show(struct device *dev,
212 struct device_attribute *attr,
215 return sprintf(buf, "%u\n", host_control_smi_type);
218 static ssize_t host_control_smi_type_store(struct device *dev,
219 struct device_attribute *attr,
220 const char *buf, size_t count)
222 host_control_smi_type = simple_strtoul(buf, NULL, 10);
226 static ssize_t host_control_on_shutdown_show(struct device *dev,
227 struct device_attribute *attr,
230 return sprintf(buf, "%u\n", host_control_on_shutdown);
233 static ssize_t host_control_on_shutdown_store(struct device *dev,
234 struct device_attribute *attr,
235 const char *buf, size_t count)
237 host_control_on_shutdown = simple_strtoul(buf, NULL, 10);
242 * dcdbas_smi_request: generate SMI request
244 * Called with smi_data_lock.
246 int dcdbas_smi_request(struct smi_cmd *smi_cmd)
248 cpumask_var_t old_mask;
251 if (smi_cmd->magic != SMI_CMD_MAGIC) {
252 dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
257 /* SMI requires CPU 0 */
258 if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
261 cpumask_copy(old_mask, ¤t->cpus_allowed);
262 set_cpus_allowed_ptr(current, cpumask_of(0));
263 if (smp_processor_id() != 0) {
264 dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n",
271 /* inb to force posted write through and make SMI happen now */
275 : /* no output args */
276 : "a" (smi_cmd->command_code),
277 "d" (smi_cmd->command_address),
284 set_cpus_allowed_ptr(current, old_mask);
285 free_cpumask_var(old_mask);
292 * The valid values are:
293 * 0: zero SMI data buffer
294 * 1: generate calling interface SMI
295 * 2: generate raw SMI
297 * User application writes smi_cmd to smi_data before telling driver
300 static ssize_t smi_request_store(struct device *dev,
301 struct device_attribute *attr,
302 const char *buf, size_t count)
304 struct smi_cmd *smi_cmd;
305 unsigned long val = simple_strtoul(buf, NULL, 10);
308 mutex_lock(&smi_data_lock);
310 if (smi_data_buf_size < sizeof(struct smi_cmd)) {
314 smi_cmd = (struct smi_cmd *)smi_data_buf;
319 ret = dcdbas_smi_request(smi_cmd);
324 /* Calling Interface SMI */
325 smi_cmd->ebx = (u32) virt_to_phys(smi_cmd->command_buffer);
326 ret = dcdbas_smi_request(smi_cmd);
331 memset(smi_data_buf, 0, smi_data_buf_size);
340 mutex_unlock(&smi_data_lock);
343 EXPORT_SYMBOL(dcdbas_smi_request);
346 * host_control_smi: generate host control SMI
348 * Caller must set up the host control command in smi_data_buf.
350 static int host_control_smi(void)
352 struct apm_cmd *apm_cmd;
359 apm_cmd = (struct apm_cmd *)smi_data_buf;
360 apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL;
362 switch (host_control_smi_type) {
363 case HC_SMITYPE_TYPE1:
364 spin_lock_irqsave(&rtc_lock, flags);
365 /* write SMI data buffer physical address */
366 data = (u8 *)&smi_data_buf_phys_addr;
367 for (index = PE1300_CMOS_CMD_STRUCT_PTR;
368 index < (PE1300_CMOS_CMD_STRUCT_PTR + 4);
371 (CMOS_BASE_PORT + CMOS_PAGE2_INDEX_PORT_PIIX4));
373 (CMOS_BASE_PORT + CMOS_PAGE2_DATA_PORT_PIIX4));
376 /* first set status to -1 as called by spec */
377 cmd_status = ESM_STATUS_CMD_UNSUCCESSFUL;
378 outb((u8) cmd_status, PCAT_APM_STATUS_PORT);
380 /* generate SMM call */
381 outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
382 spin_unlock_irqrestore(&rtc_lock, flags);
384 /* wait a few to see if it executed */
385 num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
386 while ((cmd_status = inb(PCAT_APM_STATUS_PORT))
387 == ESM_STATUS_CMD_UNSUCCESSFUL) {
389 if (num_ticks == EXPIRED_TIMER)
394 case HC_SMITYPE_TYPE2:
395 case HC_SMITYPE_TYPE3:
396 spin_lock_irqsave(&rtc_lock, flags);
397 /* write SMI data buffer physical address */
398 data = (u8 *)&smi_data_buf_phys_addr;
399 for (index = PE1400_CMOS_CMD_STRUCT_PTR;
400 index < (PE1400_CMOS_CMD_STRUCT_PTR + 4);
402 outb(index, (CMOS_BASE_PORT + CMOS_PAGE1_INDEX_PORT));
403 outb(*data, (CMOS_BASE_PORT + CMOS_PAGE1_DATA_PORT));
406 /* generate SMM call */
407 if (host_control_smi_type == HC_SMITYPE_TYPE3)
408 outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
410 outb(ESM_APM_CMD, PE1400_APM_CONTROL_PORT);
412 /* restore RTC index pointer since it was written to above */
413 CMOS_READ(RTC_REG_C);
414 spin_unlock_irqrestore(&rtc_lock, flags);
416 /* read control port back to serialize write */
417 cmd_status = inb(PE1400_APM_CONTROL_PORT);
419 /* wait a few to see if it executed */
420 num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
421 while (apm_cmd->status == ESM_STATUS_CMD_UNSUCCESSFUL) {
423 if (num_ticks == EXPIRED_TIMER)
429 dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n",
430 __func__, host_control_smi_type);
438 * dcdbas_host_control: initiate host control
440 * This function is called by the driver after the system has
441 * finished shutting down if the user application specified a
442 * host control action to perform on shutdown. It is safe to
443 * use smi_data_buf at this point because the system has finished
444 * shutting down and no userspace apps are running.
446 static void dcdbas_host_control(void)
448 struct apm_cmd *apm_cmd;
451 if (host_control_action == HC_ACTION_NONE)
454 action = host_control_action;
455 host_control_action = HC_ACTION_NONE;
458 dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__);
462 if (smi_data_buf_size < sizeof(struct apm_cmd)) {
463 dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n",
468 apm_cmd = (struct apm_cmd *)smi_data_buf;
470 /* power off takes precedence */
471 if (action & HC_ACTION_HOST_CONTROL_POWEROFF) {
472 apm_cmd->command = ESM_APM_POWER_CYCLE;
473 apm_cmd->reserved = 0;
474 *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 0;
476 } else if (action & HC_ACTION_HOST_CONTROL_POWERCYCLE) {
477 apm_cmd->command = ESM_APM_POWER_CYCLE;
478 apm_cmd->reserved = 0;
479 *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 20;
485 * dcdbas_reboot_notify: handle reboot notification for host control
487 static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code,
494 if (host_control_on_shutdown) {
495 /* firmware is going to perform host control action */
496 printk(KERN_WARNING "Please wait for shutdown "
497 "action to complete...\n");
498 dcdbas_host_control();
506 static struct notifier_block dcdbas_reboot_nb = {
507 .notifier_call = dcdbas_reboot_notify,
512 static DCDBAS_BIN_ATTR_RW(smi_data);
514 static struct bin_attribute *dcdbas_bin_attrs[] = {
519 static DCDBAS_DEV_ATTR_RW(smi_data_buf_size);
520 static DCDBAS_DEV_ATTR_RO(smi_data_buf_phys_addr);
521 static DCDBAS_DEV_ATTR_WO(smi_request);
522 static DCDBAS_DEV_ATTR_RW(host_control_action);
523 static DCDBAS_DEV_ATTR_RW(host_control_smi_type);
524 static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown);
526 static struct attribute *dcdbas_dev_attrs[] = {
527 &dev_attr_smi_data_buf_size.attr,
528 &dev_attr_smi_data_buf_phys_addr.attr,
529 &dev_attr_smi_request.attr,
530 &dev_attr_host_control_action.attr,
531 &dev_attr_host_control_smi_type.attr,
532 &dev_attr_host_control_on_shutdown.attr,
536 static struct attribute_group dcdbas_attr_group = {
537 .attrs = dcdbas_dev_attrs,
538 .bin_attrs = dcdbas_bin_attrs,
541 static int dcdbas_probe(struct platform_device *dev)
545 host_control_action = HC_ACTION_NONE;
546 host_control_smi_type = HC_SMITYPE_NONE;
551 * BIOS SMI calls require buffer addresses be in 32-bit address space.
552 * This is done by setting the DMA mask below.
554 error = dma_set_coherent_mask(&dcdbas_pdev->dev, DMA_BIT_MASK(32));
558 error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
562 register_reboot_notifier(&dcdbas_reboot_nb);
564 dev_info(&dev->dev, "%s (version %s)\n",
565 DRIVER_DESCRIPTION, DRIVER_VERSION);
570 static int dcdbas_remove(struct platform_device *dev)
572 unregister_reboot_notifier(&dcdbas_reboot_nb);
573 sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);
578 static struct platform_driver dcdbas_driver = {
582 .probe = dcdbas_probe,
583 .remove = dcdbas_remove,
586 static const struct platform_device_info dcdbas_dev_info __initconst = {
589 .dma_mask = DMA_BIT_MASK(32),
592 static struct platform_device *dcdbas_pdev_reg;
595 * dcdbas_init: initialize driver
597 static int __init dcdbas_init(void)
601 error = platform_driver_register(&dcdbas_driver);
605 dcdbas_pdev_reg = platform_device_register_full(&dcdbas_dev_info);
606 if (IS_ERR(dcdbas_pdev_reg)) {
607 error = PTR_ERR(dcdbas_pdev_reg);
608 goto err_unregister_driver;
613 err_unregister_driver:
614 platform_driver_unregister(&dcdbas_driver);
619 * dcdbas_exit: perform driver cleanup
621 static void __exit dcdbas_exit(void)
624 * make sure functions that use dcdbas_pdev are called
625 * before platform_device_unregister
627 unregister_reboot_notifier(&dcdbas_reboot_nb);
630 * We have to free the buffer here instead of dcdbas_remove
631 * because only in module exit function we can be sure that
632 * all sysfs attributes belonging to this module have been
637 platform_device_unregister(dcdbas_pdev_reg);
638 platform_driver_unregister(&dcdbas_driver);
641 module_init(dcdbas_init);
642 module_exit(dcdbas_exit);
644 MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")");
645 MODULE_VERSION(DRIVER_VERSION);
646 MODULE_AUTHOR("Dell Inc.");
647 MODULE_LICENSE("GPL");
648 /* Any System or BIOS claiming to be by Dell */
649 MODULE_ALIAS("dmi:*:[bs]vnD[Ee][Ll][Ll]*:*");