ACPI: C-States: accounting of sleep states
[linux-2.6/mini2440.git] / drivers / firmware / dcdbas.c
blob339f405ff708a999fa93018d400e4ebab2e52b25
1 /*
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
7 * Dell systems.
9 * See Documentation/dcdbas.txt for more information.
11 * Copyright (C) 1995-2005 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/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>
36 #include <linux/mutex.h>
37 #include <asm/io.h>
38 #include <asm/semaphore.h>
40 #include "dcdbas.h"
42 #define DRIVER_NAME "dcdbas"
43 #define DRIVER_VERSION "5.6.0-2"
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;
58 /**
59 * smi_data_buf_free: free SMI data buffer
61 static void smi_data_buf_free(void)
63 if (!smi_data_buf)
64 return;
66 dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
67 __FUNCTION__, smi_data_buf_phys_addr, smi_data_buf_size);
69 dma_free_coherent(&dcdbas_pdev->dev, smi_data_buf_size, smi_data_buf,
70 smi_data_buf_handle);
71 smi_data_buf = NULL;
72 smi_data_buf_handle = 0;
73 smi_data_buf_phys_addr = 0;
74 smi_data_buf_size = 0;
77 /**
78 * smi_data_buf_realloc: grow SMI data buffer if needed
80 static int smi_data_buf_realloc(unsigned long size)
82 void *buf;
83 dma_addr_t handle;
85 if (smi_data_buf_size >= size)
86 return 0;
88 if (size > MAX_SMI_DATA_BUF_SIZE)
89 return -EINVAL;
91 /* new buffer is needed */
92 buf = dma_alloc_coherent(&dcdbas_pdev->dev, size, &handle, GFP_KERNEL);
93 if (!buf) {
94 dev_dbg(&dcdbas_pdev->dev,
95 "%s: failed to allocate memory size %lu\n",
96 __FUNCTION__, size);
97 return -ENOMEM;
99 /* memory zeroed by dma_alloc_coherent */
101 if (smi_data_buf)
102 memcpy(buf, smi_data_buf, smi_data_buf_size);
104 /* free any existing buffer */
105 smi_data_buf_free();
107 /* set up new buffer for use */
108 smi_data_buf = buf;
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 __FUNCTION__, smi_data_buf_phys_addr, smi_data_buf_size);
116 return 0;
119 static ssize_t smi_data_buf_phys_addr_show(struct device *dev,
120 struct device_attribute *attr,
121 char *buf)
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,
128 char *buf)
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;
138 ssize_t ret;
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);
146 if (ret)
147 return ret;
149 return count;
152 static ssize_t smi_data_read(struct kobject *kobj, char *buf, loff_t pos,
153 size_t count)
155 size_t max_read;
156 ssize_t ret;
158 mutex_lock(&smi_data_lock);
160 if (pos >= smi_data_buf_size) {
161 ret = 0;
162 goto out;
165 max_read = smi_data_buf_size - pos;
166 ret = min(max_read, count);
167 memcpy(buf, smi_data_buf + pos, ret);
168 out:
169 mutex_unlock(&smi_data_lock);
170 return ret;
173 static ssize_t smi_data_write(struct kobject *kobj, char *buf, loff_t pos,
174 size_t count)
176 ssize_t ret;
178 mutex_lock(&smi_data_lock);
180 ret = smi_data_buf_realloc(pos + count);
181 if (ret)
182 goto out;
184 memcpy(smi_data_buf + pos, buf, count);
185 ret = count;
186 out:
187 mutex_unlock(&smi_data_lock);
188 return ret;
191 static ssize_t host_control_action_show(struct device *dev,
192 struct device_attribute *attr,
193 char *buf)
195 return sprintf(buf, "%u\n", host_control_action);
198 static ssize_t host_control_action_store(struct device *dev,
199 struct device_attribute *attr,
200 const char *buf, size_t count)
202 ssize_t ret;
204 /* make sure buffer is available for host control command */
205 mutex_lock(&smi_data_lock);
206 ret = smi_data_buf_realloc(sizeof(struct apm_cmd));
207 mutex_unlock(&smi_data_lock);
208 if (ret)
209 return ret;
211 host_control_action = simple_strtoul(buf, NULL, 10);
212 return count;
215 static ssize_t host_control_smi_type_show(struct device *dev,
216 struct device_attribute *attr,
217 char *buf)
219 return sprintf(buf, "%u\n", host_control_smi_type);
222 static ssize_t host_control_smi_type_store(struct device *dev,
223 struct device_attribute *attr,
224 const char *buf, size_t count)
226 host_control_smi_type = simple_strtoul(buf, NULL, 10);
227 return count;
230 static ssize_t host_control_on_shutdown_show(struct device *dev,
231 struct device_attribute *attr,
232 char *buf)
234 return sprintf(buf, "%u\n", host_control_on_shutdown);
237 static ssize_t host_control_on_shutdown_store(struct device *dev,
238 struct device_attribute *attr,
239 const char *buf, size_t count)
241 host_control_on_shutdown = simple_strtoul(buf, NULL, 10);
242 return count;
246 * smi_request: generate SMI request
248 * Called with smi_data_lock.
250 static int smi_request(struct smi_cmd *smi_cmd)
252 cpumask_t old_mask;
253 int ret = 0;
255 if (smi_cmd->magic != SMI_CMD_MAGIC) {
256 dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
257 __FUNCTION__);
258 return -EBADR;
261 /* SMI requires CPU 0 */
262 old_mask = current->cpus_allowed;
263 set_cpus_allowed(current, cpumask_of_cpu(0));
264 if (smp_processor_id() != 0) {
265 dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n",
266 __FUNCTION__);
267 ret = -EBUSY;
268 goto out;
271 /* generate SMI */
272 asm volatile (
273 "outb %b0,%w1"
274 : /* no output args */
275 : "a" (smi_cmd->command_code),
276 "d" (smi_cmd->command_address),
277 "b" (smi_cmd->ebx),
278 "c" (smi_cmd->ecx)
279 : "memory"
282 out:
283 set_cpus_allowed(current, old_mask);
284 return ret;
288 * smi_request_store:
290 * The valid values are:
291 * 0: zero SMI data buffer
292 * 1: generate calling interface SMI
293 * 2: generate raw SMI
295 * User application writes smi_cmd to smi_data before telling driver
296 * to generate SMI.
298 static ssize_t smi_request_store(struct device *dev,
299 struct device_attribute *attr,
300 const char *buf, size_t count)
302 struct smi_cmd *smi_cmd;
303 unsigned long val = simple_strtoul(buf, NULL, 10);
304 ssize_t ret;
306 mutex_lock(&smi_data_lock);
308 if (smi_data_buf_size < sizeof(struct smi_cmd)) {
309 ret = -ENODEV;
310 goto out;
312 smi_cmd = (struct smi_cmd *)smi_data_buf;
314 switch (val) {
315 case 2:
316 /* Raw SMI */
317 ret = smi_request(smi_cmd);
318 if (!ret)
319 ret = count;
320 break;
321 case 1:
322 /* Calling Interface SMI */
323 smi_cmd->ebx = (u32) virt_to_phys(smi_cmd->command_buffer);
324 ret = smi_request(smi_cmd);
325 if (!ret)
326 ret = count;
327 break;
328 case 0:
329 memset(smi_data_buf, 0, smi_data_buf_size);
330 ret = count;
331 break;
332 default:
333 ret = -EINVAL;
334 break;
337 out:
338 mutex_unlock(&smi_data_lock);
339 return ret;
343 * host_control_smi: generate host control SMI
345 * Caller must set up the host control command in smi_data_buf.
347 static int host_control_smi(void)
349 struct apm_cmd *apm_cmd;
350 u8 *data;
351 unsigned long flags;
352 u32 num_ticks;
353 s8 cmd_status;
354 u8 index;
356 apm_cmd = (struct apm_cmd *)smi_data_buf;
357 apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL;
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));
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);
377 /* generate SMM call */
378 outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
379 spin_unlock_irqrestore(&rtc_lock, flags);
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;
389 break;
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));
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);
409 /* restore RTC index pointer since it was written to above */
410 CMOS_READ(RTC_REG_C);
411 spin_unlock_irqrestore(&rtc_lock, flags);
413 /* read control port back to serialize write */
414 cmd_status = inb(PE1400_APM_CONTROL_PORT);
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;
423 break;
425 default:
426 dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n",
427 __FUNCTION__, host_control_smi_type);
428 return -ENOSYS;
431 return 0;
435 * dcdbas_host_control: initiate host control
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.
443 static void dcdbas_host_control(void)
445 struct apm_cmd *apm_cmd;
446 u8 action;
448 if (host_control_action == HC_ACTION_NONE)
449 return;
451 action = host_control_action;
452 host_control_action = HC_ACTION_NONE;
454 if (!smi_data_buf) {
455 dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __FUNCTION__);
456 return;
459 if (smi_data_buf_size < sizeof(struct apm_cmd)) {
460 dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n",
461 __FUNCTION__);
462 return;
465 apm_cmd = (struct apm_cmd *)smi_data_buf;
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();
482 * dcdbas_reboot_notify: handle reboot notification for host control
484 static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code,
485 void *unused)
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 */
493 printk(KERN_WARNING "Please wait for shutdown "
494 "action to complete...\n");
495 dcdbas_host_control();
497 break;
500 return NOTIFY_DONE;
503 static struct notifier_block dcdbas_reboot_nb = {
504 .notifier_call = dcdbas_reboot_notify,
505 .next = NULL,
506 .priority = INT_MIN
509 static DCDBAS_BIN_ATTR_RW(smi_data);
511 static struct bin_attribute *dcdbas_bin_attrs[] = {
512 &bin_attr_smi_data,
513 NULL
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);
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,
530 NULL
533 static struct attribute_group dcdbas_attr_group = {
534 .attrs = dcdbas_dev_attrs,
537 static int __devinit dcdbas_probe(struct platform_device *dev)
539 int i, error;
541 host_control_action = HC_ACTION_NONE;
542 host_control_smi_type = HC_SMITYPE_NONE;
545 * BIOS SMI calls require buffer addresses be in 32-bit address space.
546 * This is done by setting the DMA mask below.
548 dcdbas_pdev->dev.coherent_dma_mask = DMA_32BIT_MASK;
549 dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask;
551 error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
552 if (error)
553 return error;
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]);
562 sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
563 return error;
567 register_reboot_notifier(&dcdbas_reboot_nb);
569 dev_info(&dev->dev, "%s (version %s)\n",
570 DRIVER_DESCRIPTION, DRIVER_VERSION);
572 return 0;
575 static int __devexit dcdbas_remove(struct platform_device *dev)
577 int i;
579 unregister_reboot_notifier(&dcdbas_reboot_nb);
580 for (i = 0; dcdbas_bin_attrs[i]; i++)
581 sysfs_remove_bin_file(&dev->dev.kobj, dcdbas_bin_attrs[i]);
582 sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);
584 return 0;
587 static struct platform_driver dcdbas_driver = {
588 .driver = {
589 .name = DRIVER_NAME,
590 .owner = THIS_MODULE,
592 .probe = dcdbas_probe,
593 .remove = __devexit_p(dcdbas_remove),
597 * dcdbas_init: initialize driver
599 static int __init dcdbas_init(void)
601 int error;
603 error = platform_driver_register(&dcdbas_driver);
604 if (error)
605 return error;
607 dcdbas_pdev = platform_device_alloc(DRIVER_NAME, -1);
608 if (!dcdbas_pdev) {
609 error = -ENOMEM;
610 goto err_unregister_driver;
613 error = platform_device_add(dcdbas_pdev);
614 if (error)
615 goto err_free_device;
617 return 0;
619 err_free_device:
620 platform_device_put(dcdbas_pdev);
621 err_unregister_driver:
622 platform_driver_unregister(&dcdbas_driver);
623 return error;
627 * dcdbas_exit: perform driver cleanup
629 static void __exit dcdbas_exit(void)
632 * make sure functions that use dcdbas_pdev are called
633 * before platform_device_unregister
635 unregister_reboot_notifier(&dcdbas_reboot_nb);
636 smi_data_buf_free();
637 platform_device_unregister(dcdbas_pdev);
638 platform_driver_unregister(&dcdbas_driver);
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.
646 smi_data_buf_free();
649 module_init(dcdbas_init);
650 module_exit(dcdbas_exit);
652 MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")");
653 MODULE_VERSION(DRIVER_VERSION);
654 MODULE_AUTHOR("Dell Inc.");
655 MODULE_LICENSE("GPL");