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 * 11 * Copyright (C) 1995-2006 Dell Inc. 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 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> 38#include <asm/io.h> 39 40#include "dcdbas.h" 41 42#define DRIVER_NAME "dcdbas" 43#define DRIVER_VERSION "5.6.0-3.2" 44#define DRIVER_DESCRIPTION "Dell Systems Management Base Driver" 45 46static struct platform_device *dcdbas_pdev; 47 48static u8 *smi_data_buf; 49static dma_addr_t smi_data_buf_handle; 50static unsigned long smi_data_buf_size; 51static u32 smi_data_buf_phys_addr; 52static DEFINE_MUTEX(smi_data_lock); 53 54static unsigned int host_control_action; 55static unsigned int host_control_smi_type; 56static unsigned int host_control_on_shutdown; 57 58/** 59 * smi_data_buf_free: free SMI data buffer 60 */ 61static void smi_data_buf_free(void) 62{ 63 if (!smi_data_buf) 64 return; 65 66 dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", 67 __func__, smi_data_buf_phys_addr, smi_data_buf_size); 68 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; 75} 76 77/** 78 * smi_data_buf_realloc: grow SMI data buffer if needed 79 */ 80static int smi_data_buf_realloc(unsigned long size) 81{ 82 void *buf; 83 dma_addr_t handle; 84 85 if (smi_data_buf_size >= size) 86 return 0; 87 88 if (size > MAX_SMI_DATA_BUF_SIZE) 89 return -EINVAL; 90 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 __func__, size); 97 return -ENOMEM; 98 } 99 /* memory zeroed by dma_alloc_coherent */ 100 101 if (smi_data_buf) 102 memcpy(buf, smi_data_buf, smi_data_buf_size); 103 104 /* free any existing buffer */ 105 smi_data_buf_free(); 106 107 /* 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; 112 113 dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", 114 __func__, smi_data_buf_phys_addr, smi_data_buf_size); 115 116 return 0; 117} 118 119static ssize_t smi_data_buf_phys_addr_show(struct device *dev, 120 struct device_attribute *attr, 121 char *buf) 122{ 123 return sprintf(buf, "%x\n", smi_data_buf_phys_addr); 124} 125 126static ssize_t smi_data_buf_size_show(struct device *dev, 127 struct device_attribute *attr, 128 char *buf) 129{ 130 return sprintf(buf, "%lu\n", smi_data_buf_size); 131} 132 133static ssize_t smi_data_buf_size_store(struct device *dev, 134 struct device_attribute *attr, 135 const char *buf, size_t count) 136{ 137 unsigned long buf_size; 138 ssize_t ret; 139 140 buf_size = simple_strtoul(buf, NULL, 10); 141 142 /* 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; 148 149 return count; 150} 151 152static 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) 155{ 156 ssize_t ret; 157 158 mutex_lock(&smi_data_lock); 159 ret = memory_read_from_buffer(buf, count, &pos, smi_data_buf, 160 smi_data_buf_size); 161 mutex_unlock(&smi_data_lock); 162 return ret; 163} 164 165static 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) 168{ 169 ssize_t ret; 170 171 if ((pos + count) > MAX_SMI_DATA_BUF_SIZE) 172 return -EINVAL; 173 174 mutex_lock(&smi_data_lock); 175 176 ret = smi_data_buf_realloc(pos + count); 177 if (ret) 178 goto out; 179 180 memcpy(smi_data_buf + pos, buf, count); 181 ret = count; 182out: 183 mutex_unlock(&smi_data_lock); 184 return ret; 185} 186 187static ssize_t host_control_action_show(struct device *dev, 188 struct device_attribute *attr, 189 char *buf) 190{ 191 return sprintf(buf, "%u\n", host_control_action); 192} 193 194static ssize_t host_control_action_store(struct device *dev, 195 struct device_attribute *attr, 196 const char *buf, size_t count) 197{ 198 ssize_t ret; 199 200 /* 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); 204 if (ret) 205 return ret; 206 207 host_control_action = simple_strtoul(buf, NULL, 10); 208 return count; 209} 210 211static ssize_t host_control_smi_type_show(struct device *dev, 212 struct device_attribute *attr, 213 char *buf) 214{ 215 return sprintf(buf, "%u\n", host_control_smi_type); 216} 217 218static ssize_t host_control_smi_type_store(struct device *dev, 219 struct device_attribute *attr, 220 const char *buf, size_t count) 221{ 222 host_control_smi_type = simple_strtoul(buf, NULL, 10); 223 return count; 224} 225 226static ssize_t host_control_on_shutdown_show(struct device *dev, 227 struct device_attribute *attr, 228 char *buf) 229{ 230 return sprintf(buf, "%u\n", host_control_on_shutdown); 231} 232 233static ssize_t host_control_on_shutdown_store(struct device *dev, 234 struct device_attribute *attr, 235 const char *buf, size_t count) 236{ 237 host_control_on_shutdown = simple_strtoul(buf, NULL, 10); 238 return count; 239} 240 241/** 242 * dcdbas_smi_request: generate SMI request 243 * 244 * Called with smi_data_lock. 245 */ 246int dcdbas_smi_request(struct smi_cmd *smi_cmd) 247{ 248 cpumask_var_t old_mask; 249 int ret = 0; 250 251 if (smi_cmd->magic != SMI_CMD_MAGIC) { 252 dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n", 253 __func__); 254 return -EBADR; 255 } 256 257 /* SMI requires CPU 0 */ 258 if (!alloc_cpumask_var(&old_mask, GFP_KERNEL)) 259 return -ENOMEM; 260 261 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", 265 __func__); 266 ret = -EBUSY; 267 goto out; 268 } 269 270 /* generate SMI */ 271 /* inb to force posted write through and make SMI happen now */ 272 asm volatile ( 273 "outb %b0,%w1\n" 274 "inb %w1" 275 : /* no output args */ 276 : "a" (smi_cmd->command_code), 277 "d" (smi_cmd->command_address), 278 "b" (smi_cmd->ebx), 279 "c" (smi_cmd->ecx) 280 : "memory" 281 ); 282 283out: 284 set_cpus_allowed_ptr(current, old_mask); 285 free_cpumask_var(old_mask); 286 return ret; 287} 288 289/** 290 * smi_request_store: 291 * 292 * The valid values are: 293 * 0: zero SMI data buffer 294 * 1: generate calling interface SMI 295 * 2: generate raw SMI 296 * 297 * User application writes smi_cmd to smi_data before telling driver 298 * to generate SMI. 299 */ 300static ssize_t smi_request_store(struct device *dev, 301 struct device_attribute *attr, 302 const char *buf, size_t count) 303{ 304 struct smi_cmd *smi_cmd; 305 unsigned long val = simple_strtoul(buf, NULL, 10); 306 ssize_t ret; 307 308 mutex_lock(&smi_data_lock); 309 310 if (smi_data_buf_size < sizeof(struct smi_cmd)) { 311 ret = -ENODEV; 312 goto out; 313 } 314 smi_cmd = (struct smi_cmd *)smi_data_buf; 315 316 switch (val) { 317 case 2: 318 /* Raw SMI */ 319 ret = dcdbas_smi_request(smi_cmd); 320 if (!ret) 321 ret = count; 322 break; 323 case 1: 324 /* Calling Interface SMI */ 325 smi_cmd->ebx = (u32) virt_to_phys(smi_cmd->command_buffer); 326 ret = dcdbas_smi_request(smi_cmd); 327 if (!ret) 328 ret = count; 329 break; 330 case 0: 331 memset(smi_data_buf, 0, smi_data_buf_size); 332 ret = count; 333 break; 334 default: 335 ret = -EINVAL; 336 break; 337 } 338 339out: 340 mutex_unlock(&smi_data_lock); 341 return ret; 342} 343EXPORT_SYMBOL(dcdbas_smi_request); 344 345/** 346 * host_control_smi: generate host control SMI 347 * 348 * Caller must set up the host control command in smi_data_buf. 349 */ 350static int host_control_smi(void) 351{ 352 struct apm_cmd *apm_cmd; 353 u8 *data; 354 unsigned long flags; 355 u32 num_ticks; 356 s8 cmd_status; 357 u8 index; 358 359 apm_cmd = (struct apm_cmd *)smi_data_buf; 360 apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL; 361 362 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); 369 index++, data++) { 370 outb(index, 371 (CMOS_BASE_PORT + CMOS_PAGE2_INDEX_PORT_PIIX4)); 372 outb(*data, 373 (CMOS_BASE_PORT + CMOS_PAGE2_DATA_PORT_PIIX4)); 374 } 375 376 /* 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); 379 380 /* generate SMM call */ 381 outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT); 382 spin_unlock_irqrestore(&rtc_lock, flags); 383 384 /* 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) { 388 num_ticks--; 389 if (num_ticks == EXPIRED_TIMER) 390 return -ETIME; 391 } 392 break; 393 394 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); 401 index++, data++) { 402 outb(index, (CMOS_BASE_PORT + CMOS_PAGE1_INDEX_PORT)); 403 outb(*data, (CMOS_BASE_PORT + CMOS_PAGE1_DATA_PORT)); 404 } 405 406 /* generate SMM call */ 407 if (host_control_smi_type == HC_SMITYPE_TYPE3) 408 outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT); 409 else 410 outb(ESM_APM_CMD, PE1400_APM_CONTROL_PORT); 411 412 /* restore RTC index pointer since it was written to above */ 413 CMOS_READ(RTC_REG_C); 414 spin_unlock_irqrestore(&rtc_lock, flags); 415 416 /* read control port back to serialize write */ 417 cmd_status = inb(PE1400_APM_CONTROL_PORT); 418 419 /* 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) { 422 num_ticks--; 423 if (num_ticks == EXPIRED_TIMER) 424 return -ETIME; 425 } 426 break; 427 428 default: 429 dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n", 430 __func__, host_control_smi_type); 431 return -ENOSYS; 432 } 433 434 return 0; 435} 436 437/** 438 * dcdbas_host_control: initiate host control 439 * 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. 445 */ 446static void dcdbas_host_control(void) 447{ 448 struct apm_cmd *apm_cmd; 449 u8 action; 450 451 if (host_control_action == HC_ACTION_NONE) 452 return; 453 454 action = host_control_action; 455 host_control_action = HC_ACTION_NONE; 456 457 if (!smi_data_buf) { 458 dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__); 459 return; 460 } 461 462 if (smi_data_buf_size < sizeof(struct apm_cmd)) { 463 dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n", 464 __func__); 465 return; 466 } 467 468 apm_cmd = (struct apm_cmd *)smi_data_buf; 469 470 /* 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; 475 host_control_smi(); 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; 480 host_control_smi(); 481 } 482} 483 484/** 485 * dcdbas_reboot_notify: handle reboot notification for host control 486 */ 487static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code, 488 void *unused) 489{ 490 switch (code) { 491 case SYS_DOWN: 492 case SYS_HALT: 493 case SYS_POWER_OFF: 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(); 499 } 500 break; 501 } 502 503 return NOTIFY_DONE; 504} 505 506static struct notifier_block dcdbas_reboot_nb = { 507 .notifier_call = dcdbas_reboot_notify, 508 .next = NULL, 509 .priority = INT_MIN 510}; 511 512static DCDBAS_BIN_ATTR_RW(smi_data); 513 514static struct bin_attribute *dcdbas_bin_attrs[] = { 515 &bin_attr_smi_data, 516 NULL 517}; 518 519static DCDBAS_DEV_ATTR_RW(smi_data_buf_size); 520static DCDBAS_DEV_ATTR_RO(smi_data_buf_phys_addr); 521static DCDBAS_DEV_ATTR_WO(smi_request); 522static DCDBAS_DEV_ATTR_RW(host_control_action); 523static DCDBAS_DEV_ATTR_RW(host_control_smi_type); 524static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown); 525 526static 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, 533 NULL 534}; 535 536static struct attribute_group dcdbas_attr_group = { 537 .attrs = dcdbas_dev_attrs, 538}; 539 540static int __devinit dcdbas_probe(struct platform_device *dev) 541{ 542 int i, error; 543 544 host_control_action = HC_ACTION_NONE; 545 host_control_smi_type = HC_SMITYPE_NONE; 546 547 /* 548 * BIOS SMI calls require buffer addresses be in 32-bit address space. 549 * This is done by setting the DMA mask below. 550 */ 551 dcdbas_pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32); 552 dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask; 553 554 error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group); 555 if (error) 556 return error; 557 558 for (i = 0; dcdbas_bin_attrs[i]; i++) { 559 error = sysfs_create_bin_file(&dev->dev.kobj, 560 dcdbas_bin_attrs[i]); 561 if (error) { 562 while (--i >= 0) 563 sysfs_remove_bin_file(&dev->dev.kobj, 564 dcdbas_bin_attrs[i]); 565 sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group); 566 return error; 567 } 568 } 569 570 register_reboot_notifier(&dcdbas_reboot_nb); 571 572 dev_info(&dev->dev, "%s (version %s)\n", 573 DRIVER_DESCRIPTION, DRIVER_VERSION); 574 575 return 0; 576} 577 578static int __devexit dcdbas_remove(struct platform_device *dev) 579{ 580 int i; 581 582 unregister_reboot_notifier(&dcdbas_reboot_nb); 583 for (i = 0; dcdbas_bin_attrs[i]; i++) 584 sysfs_remove_bin_file(&dev->dev.kobj, dcdbas_bin_attrs[i]); 585 sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group); 586 587 return 0; 588} 589 590static struct platform_driver dcdbas_driver = { 591 .driver = { 592 .name = DRIVER_NAME, 593 .owner = THIS_MODULE, 594 }, 595 .probe = dcdbas_probe, 596 .remove = __devexit_p(dcdbas_remove), 597}; 598 599/** 600 * dcdbas_init: initialize driver 601 */ 602static int __init dcdbas_init(void) 603{ 604 int error; 605 606 error = platform_driver_register(&dcdbas_driver); 607 if (error) 608 return error; 609 610 dcdbas_pdev = platform_device_alloc(DRIVER_NAME, -1); 611 if (!dcdbas_pdev) { 612 error = -ENOMEM; 613 goto err_unregister_driver; 614 } 615 616 error = platform_device_add(dcdbas_pdev); 617 if (error) 618 goto err_free_device; 619 620 return 0; 621 622 err_free_device: 623 platform_device_put(dcdbas_pdev); 624 err_unregister_driver: 625 platform_driver_unregister(&dcdbas_driver); 626 return error; 627} 628 629/** 630 * dcdbas_exit: perform driver cleanup 631 */ 632static void __exit dcdbas_exit(void) 633{ 634 /* 635 * make sure functions that use dcdbas_pdev are called 636 * before platform_device_unregister 637 */ 638 unregister_reboot_notifier(&dcdbas_reboot_nb); 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(); 647 platform_device_unregister(dcdbas_pdev); 648 platform_driver_unregister(&dcdbas_driver); 649} 650 651module_init(dcdbas_init); 652module_exit(dcdbas_exit); 653 654MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")"); 655MODULE_VERSION(DRIVER_VERSION); 656MODULE_AUTHOR("Dell Inc."); 657MODULE_LICENSE("GPL"); 658/* Any System or BIOS claiming to be by Dell */ 659MODULE_ALIAS("dmi:*:[bs]vnD[Ee][Ll][Ll]*:*"); 660