1 /* 2 * PowerMac G5 SMU driver 3 * 4 * Copyright 2004 J. Mayer <l_indien@magic.fr> 5 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp. 6 * 7 * Released under the term of the GNU GPL v2. 8 */ 9 10 /* 11 * TODO: 12 * - maybe add timeout to commands ? 13 * - blocking version of time functions 14 * - polling version of i2c commands (including timer that works with 15 * interrutps off) 16 * - maybe avoid some data copies with i2c by directly using the smu cmd 17 * buffer and a lower level internal interface 18 * - understand SMU -> CPU events and implement reception of them via 19 * the userland interface 20 */ 21 22 #include <linux/config.h> 23 #include <linux/types.h> 24 #include <linux/kernel.h> 25 #include <linux/device.h> 26 #include <linux/dmapool.h> 27 #include <linux/bootmem.h> 28 #include <linux/vmalloc.h> 29 #include <linux/highmem.h> 30 #include <linux/jiffies.h> 31 #include <linux/interrupt.h> 32 #include <linux/rtc.h> 33 #include <linux/completion.h> 34 #include <linux/miscdevice.h> 35 #include <linux/delay.h> 36 #include <linux/sysdev.h> 37 #include <linux/poll.h> 38 39 #include <asm/byteorder.h> 40 #include <asm/io.h> 41 #include <asm/prom.h> 42 #include <asm/machdep.h> 43 #include <asm/pmac_feature.h> 44 #include <asm/smu.h> 45 #include <asm/sections.h> 46 #include <asm/abs_addr.h> 47 #include <asm/uaccess.h> 48 #include <asm/of_device.h> 49 50 #define VERSION "0.7" 51 #define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp." 52 53 #undef DEBUG_SMU 54 55 #ifdef DEBUG_SMU 56 #define DPRINTK(fmt, args...) do { udbg_printf(KERN_DEBUG fmt , ##args); } while (0) 57 #else 58 #define DPRINTK(fmt, args...) do { } while (0) 59 #endif 60 61 /* 62 * This is the command buffer passed to the SMU hardware 63 */ 64 #define SMU_MAX_DATA 254 65 66 struct smu_cmd_buf { 67 u8 cmd; 68 u8 length; 69 u8 data[SMU_MAX_DATA]; 70 }; 71 72 struct smu_device { 73 spinlock_t lock; 74 struct device_node *of_node; 75 struct of_device *of_dev; 76 int doorbell; /* doorbell gpio */ 77 u32 __iomem *db_buf; /* doorbell buffer */ 78 int db_irq; 79 int msg; 80 int msg_irq; 81 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ 82 u32 cmd_buf_abs; /* command buffer absolute */ 83 struct list_head cmd_list; 84 struct smu_cmd *cmd_cur; /* pending command */ 85 struct list_head cmd_i2c_list; 86 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 87 struct timer_list i2c_timer; 88 }; 89 90 /* 91 * I don't think there will ever be more than one SMU, so 92 * for now, just hard code that 93 */ 94 static struct smu_device *smu; 95 static DECLARE_MUTEX(smu_part_access); 96 97 /* 98 * SMU driver low level stuff 99 */ 100 101 static void smu_start_cmd(void) 102 { 103 unsigned long faddr, fend; 104 struct smu_cmd *cmd; 105 106 if (list_empty(&smu->cmd_list)) 107 return; 108 109 /* Fetch first command in queue */ 110 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 111 smu->cmd_cur = cmd; 112 list_del(&cmd->link); 113 114 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 115 cmd->data_len); 116 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 117 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 118 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 119 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 120 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 121 122 /* Fill the SMU command buffer */ 123 smu->cmd_buf->cmd = cmd->cmd; 124 smu->cmd_buf->length = cmd->data_len; 125 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 126 127 /* Flush command and data to RAM */ 128 faddr = (unsigned long)smu->cmd_buf; 129 fend = faddr + smu->cmd_buf->length + 2; 130 flush_inval_dcache_range(faddr, fend); 131 132 /* This isn't exactly a DMA mapping here, I suspect 133 * the SMU is actually communicating with us via i2c to the 134 * northbridge or the CPU to access RAM. 135 */ 136 writel(smu->cmd_buf_abs, smu->db_buf); 137 138 /* Ring the SMU doorbell */ 139 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 140 } 141 142 143 static irqreturn_t smu_db_intr(int irq, void *arg, struct pt_regs *regs) 144 { 145 unsigned long flags; 146 struct smu_cmd *cmd; 147 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 148 void *misc = NULL; 149 u8 gpio; 150 int rc = 0; 151 152 /* SMU completed the command, well, we hope, let's make sure 153 * of it 154 */ 155 spin_lock_irqsave(&smu->lock, flags); 156 157 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 158 if ((gpio & 7) != 7) { 159 spin_unlock_irqrestore(&smu->lock, flags); 160 return IRQ_HANDLED; 161 } 162 163 cmd = smu->cmd_cur; 164 smu->cmd_cur = NULL; 165 if (cmd == NULL) 166 goto bail; 167 168 if (rc == 0) { 169 unsigned long faddr; 170 int reply_len; 171 u8 ack; 172 173 /* CPU might have brought back the cache line, so we need 174 * to flush again before peeking at the SMU response. We 175 * flush the entire buffer for now as we haven't read the 176 * reply lenght (it's only 2 cache lines anyway) 177 */ 178 faddr = (unsigned long)smu->cmd_buf; 179 flush_inval_dcache_range(faddr, faddr + 256); 180 181 /* Now check ack */ 182 ack = (~cmd->cmd) & 0xff; 183 if (ack != smu->cmd_buf->cmd) { 184 DPRINTK("SMU: incorrect ack, want %x got %x\n", 185 ack, smu->cmd_buf->cmd); 186 rc = -EIO; 187 } 188 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 189 DPRINTK("SMU: reply len: %d\n", reply_len); 190 if (reply_len > cmd->reply_len) { 191 printk(KERN_WARNING "SMU: reply buffer too small," 192 "got %d bytes for a %d bytes buffer\n", 193 reply_len, cmd->reply_len); 194 reply_len = cmd->reply_len; 195 } 196 cmd->reply_len = reply_len; 197 if (cmd->reply_buf && reply_len) 198 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 199 } 200 201 /* Now complete the command. Write status last in order as we lost 202 * ownership of the command structure as soon as it's no longer -1 203 */ 204 done = cmd->done; 205 misc = cmd->misc; 206 mb(); 207 cmd->status = rc; 208 bail: 209 /* Start next command if any */ 210 smu_start_cmd(); 211 spin_unlock_irqrestore(&smu->lock, flags); 212 213 /* Call command completion handler if any */ 214 if (done) 215 done(cmd, misc); 216 217 /* It's an edge interrupt, nothing to do */ 218 return IRQ_HANDLED; 219 } 220 221 222 static irqreturn_t smu_msg_intr(int irq, void *arg, struct pt_regs *regs) 223 { 224 /* I don't quite know what to do with this one, we seem to never 225 * receive it, so I suspect we have to arm it someway in the SMU 226 * to start getting events that way. 227 */ 228 229 printk(KERN_INFO "SMU: message interrupt !\n"); 230 231 /* It's an edge interrupt, nothing to do */ 232 return IRQ_HANDLED; 233 } 234 235 236 /* 237 * Queued command management. 238 * 239 */ 240 241 int smu_queue_cmd(struct smu_cmd *cmd) 242 { 243 unsigned long flags; 244 245 if (smu == NULL) 246 return -ENODEV; 247 if (cmd->data_len > SMU_MAX_DATA || 248 cmd->reply_len > SMU_MAX_DATA) 249 return -EINVAL; 250 251 cmd->status = 1; 252 spin_lock_irqsave(&smu->lock, flags); 253 list_add_tail(&cmd->link, &smu->cmd_list); 254 if (smu->cmd_cur == NULL) 255 smu_start_cmd(); 256 spin_unlock_irqrestore(&smu->lock, flags); 257 258 return 0; 259 } 260 EXPORT_SYMBOL(smu_queue_cmd); 261 262 263 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 264 unsigned int data_len, 265 void (*done)(struct smu_cmd *cmd, void *misc), 266 void *misc, ...) 267 { 268 struct smu_cmd *cmd = &scmd->cmd; 269 va_list list; 270 int i; 271 272 if (data_len > sizeof(scmd->buffer)) 273 return -EINVAL; 274 275 memset(scmd, 0, sizeof(*scmd)); 276 cmd->cmd = command; 277 cmd->data_len = data_len; 278 cmd->data_buf = scmd->buffer; 279 cmd->reply_len = sizeof(scmd->buffer); 280 cmd->reply_buf = scmd->buffer; 281 cmd->done = done; 282 cmd->misc = misc; 283 284 va_start(list, misc); 285 for (i = 0; i < data_len; ++i) 286 scmd->buffer[i] = (u8)va_arg(list, int); 287 va_end(list); 288 289 return smu_queue_cmd(cmd); 290 } 291 EXPORT_SYMBOL(smu_queue_simple); 292 293 294 void smu_poll(void) 295 { 296 u8 gpio; 297 298 if (smu == NULL) 299 return; 300 301 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 302 if ((gpio & 7) == 7) 303 smu_db_intr(smu->db_irq, smu, NULL); 304 } 305 EXPORT_SYMBOL(smu_poll); 306 307 308 void smu_done_complete(struct smu_cmd *cmd, void *misc) 309 { 310 struct completion *comp = misc; 311 312 complete(comp); 313 } 314 EXPORT_SYMBOL(smu_done_complete); 315 316 317 void smu_spinwait_cmd(struct smu_cmd *cmd) 318 { 319 while(cmd->status == 1) 320 smu_poll(); 321 } 322 EXPORT_SYMBOL(smu_spinwait_cmd); 323 324 325 /* RTC low level commands */ 326 static inline int bcd2hex (int n) 327 { 328 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 329 } 330 331 332 static inline int hex2bcd (int n) 333 { 334 return ((n / 10) << 4) + (n % 10); 335 } 336 337 338 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 339 struct rtc_time *time) 340 { 341 cmd_buf->cmd = 0x8e; 342 cmd_buf->length = 8; 343 cmd_buf->data[0] = 0x80; 344 cmd_buf->data[1] = hex2bcd(time->tm_sec); 345 cmd_buf->data[2] = hex2bcd(time->tm_min); 346 cmd_buf->data[3] = hex2bcd(time->tm_hour); 347 cmd_buf->data[4] = time->tm_wday; 348 cmd_buf->data[5] = hex2bcd(time->tm_mday); 349 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 350 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 351 } 352 353 354 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 355 { 356 struct smu_simple_cmd cmd; 357 int rc; 358 359 if (smu == NULL) 360 return -ENODEV; 361 362 memset(time, 0, sizeof(struct rtc_time)); 363 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 364 SMU_CMD_RTC_GET_DATETIME); 365 if (rc) 366 return rc; 367 smu_spinwait_simple(&cmd); 368 369 time->tm_sec = bcd2hex(cmd.buffer[0]); 370 time->tm_min = bcd2hex(cmd.buffer[1]); 371 time->tm_hour = bcd2hex(cmd.buffer[2]); 372 time->tm_wday = bcd2hex(cmd.buffer[3]); 373 time->tm_mday = bcd2hex(cmd.buffer[4]); 374 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 375 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 376 377 return 0; 378 } 379 380 381 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 382 { 383 struct smu_simple_cmd cmd; 384 int rc; 385 386 if (smu == NULL) 387 return -ENODEV; 388 389 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 390 SMU_CMD_RTC_SET_DATETIME, 391 hex2bcd(time->tm_sec), 392 hex2bcd(time->tm_min), 393 hex2bcd(time->tm_hour), 394 time->tm_wday, 395 hex2bcd(time->tm_mday), 396 hex2bcd(time->tm_mon) + 1, 397 hex2bcd(time->tm_year - 100)); 398 if (rc) 399 return rc; 400 smu_spinwait_simple(&cmd); 401 402 return 0; 403 } 404 405 406 void smu_shutdown(void) 407 { 408 struct smu_simple_cmd cmd; 409 410 if (smu == NULL) 411 return; 412 413 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 414 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 415 return; 416 smu_spinwait_simple(&cmd); 417 for (;;) 418 ; 419 } 420 421 422 void smu_restart(void) 423 { 424 struct smu_simple_cmd cmd; 425 426 if (smu == NULL) 427 return; 428 429 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 430 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 431 return; 432 smu_spinwait_simple(&cmd); 433 for (;;) 434 ; 435 } 436 437 438 int smu_present(void) 439 { 440 return smu != NULL; 441 } 442 EXPORT_SYMBOL(smu_present); 443 444 445 int __init smu_init (void) 446 { 447 struct device_node *np; 448 u32 *data; 449 450 np = of_find_node_by_type(NULL, "smu"); 451 if (np == NULL) 452 return -ENODEV; 453 454 printk(KERN_INFO "SMU driver %s %s\n", VERSION, AUTHOR); 455 456 if (smu_cmdbuf_abs == 0) { 457 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 458 return -EINVAL; 459 } 460 461 smu = alloc_bootmem(sizeof(struct smu_device)); 462 if (smu == NULL) 463 return -ENOMEM; 464 memset(smu, 0, sizeof(*smu)); 465 466 spin_lock_init(&smu->lock); 467 INIT_LIST_HEAD(&smu->cmd_list); 468 INIT_LIST_HEAD(&smu->cmd_i2c_list); 469 smu->of_node = np; 470 smu->db_irq = NO_IRQ; 471 smu->msg_irq = NO_IRQ; 472 init_timer(&smu->i2c_timer); 473 474 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 475 * 32 bits value safely 476 */ 477 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 478 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); 479 480 np = of_find_node_by_name(NULL, "smu-doorbell"); 481 if (np == NULL) { 482 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 483 goto fail; 484 } 485 data = (u32 *)get_property(np, "reg", NULL); 486 if (data == NULL) { 487 of_node_put(np); 488 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 489 goto fail; 490 } 491 492 /* Current setup has one doorbell GPIO that does both doorbell 493 * and ack. GPIOs are at 0x50, best would be to find that out 494 * in the device-tree though. 495 */ 496 smu->doorbell = *data; 497 if (smu->doorbell < 0x50) 498 smu->doorbell += 0x50; 499 if (np->n_intrs > 0) 500 smu->db_irq = np->intrs[0].line; 501 502 of_node_put(np); 503 504 /* Now look for the smu-interrupt GPIO */ 505 do { 506 np = of_find_node_by_name(NULL, "smu-interrupt"); 507 if (np == NULL) 508 break; 509 data = (u32 *)get_property(np, "reg", NULL); 510 if (data == NULL) { 511 of_node_put(np); 512 break; 513 } 514 smu->msg = *data; 515 if (smu->msg < 0x50) 516 smu->msg += 0x50; 517 if (np->n_intrs > 0) 518 smu->msg_irq = np->intrs[0].line; 519 of_node_put(np); 520 } while(0); 521 522 /* Doorbell buffer is currently hard-coded, I didn't find a proper 523 * device-tree entry giving the address. Best would probably to use 524 * an offset for K2 base though, but let's do it that way for now. 525 */ 526 smu->db_buf = ioremap(0x8000860c, 0x1000); 527 if (smu->db_buf == NULL) { 528 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 529 goto fail; 530 } 531 532 sys_ctrler = SYS_CTRLER_SMU; 533 return 0; 534 535 fail: 536 smu = NULL; 537 return -ENXIO; 538 539 } 540 541 542 static int smu_late_init(void) 543 { 544 if (!smu) 545 return 0; 546 547 /* 548 * Try to request the interrupts 549 */ 550 551 if (smu->db_irq != NO_IRQ) { 552 if (request_irq(smu->db_irq, smu_db_intr, 553 SA_SHIRQ, "SMU doorbell", smu) < 0) { 554 printk(KERN_WARNING "SMU: can't " 555 "request interrupt %d\n", 556 smu->db_irq); 557 smu->db_irq = NO_IRQ; 558 } 559 } 560 561 if (smu->msg_irq != NO_IRQ) { 562 if (request_irq(smu->msg_irq, smu_msg_intr, 563 SA_SHIRQ, "SMU message", smu) < 0) { 564 printk(KERN_WARNING "SMU: can't " 565 "request interrupt %d\n", 566 smu->msg_irq); 567 smu->msg_irq = NO_IRQ; 568 } 569 } 570 571 return 0; 572 } 573 arch_initcall(smu_late_init); 574 575 /* 576 * sysfs visibility 577 */ 578 579 static void smu_expose_childs(void *unused) 580 { 581 struct device_node *np; 582 583 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) { 584 if (device_is_compatible(np, "smu-i2c")) { 585 char name[32]; 586 u32 *reg = (u32 *)get_property(np, "reg", NULL); 587 588 if (reg == NULL) 589 continue; 590 sprintf(name, "smu-i2c-%02x", *reg); 591 of_platform_device_create(np, name, &smu->of_dev->dev); 592 } 593 if (device_is_compatible(np, "smu-sensors")) 594 of_platform_device_create(np, "smu-sensors", &smu->of_dev->dev); 595 } 596 597 } 598 599 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs, NULL); 600 601 static int smu_platform_probe(struct of_device* dev, 602 const struct of_device_id *match) 603 { 604 if (!smu) 605 return -ENODEV; 606 smu->of_dev = dev; 607 608 /* 609 * Ok, we are matched, now expose all i2c busses. We have to defer 610 * that unfortunately or it would deadlock inside the device model 611 */ 612 schedule_work(&smu_expose_childs_work); 613 614 return 0; 615 } 616 617 static struct of_device_id smu_platform_match[] = 618 { 619 { 620 .type = "smu", 621 }, 622 {}, 623 }; 624 625 static struct of_platform_driver smu_of_platform_driver = 626 { 627 .name = "smu", 628 .match_table = smu_platform_match, 629 .probe = smu_platform_probe, 630 }; 631 632 static int __init smu_init_sysfs(void) 633 { 634 int rc; 635 636 /* 637 * Due to sysfs bogosity, a sysdev is not a real device, so 638 * we should in fact create both if we want sysdev semantics 639 * for power management. 640 * For now, we don't power manage machines with an SMU chip, 641 * I'm a bit too far from figuring out how that works with those 642 * new chipsets, but that will come back and bite us 643 */ 644 rc = of_register_driver(&smu_of_platform_driver); 645 return 0; 646 } 647 648 device_initcall(smu_init_sysfs); 649 650 struct of_device *smu_get_ofdev(void) 651 { 652 if (!smu) 653 return NULL; 654 return smu->of_dev; 655 } 656 657 EXPORT_SYMBOL_GPL(smu_get_ofdev); 658 659 /* 660 * i2c interface 661 */ 662 663 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 664 { 665 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 666 void *misc = cmd->misc; 667 unsigned long flags; 668 669 /* Check for read case */ 670 if (!fail && cmd->read) { 671 if (cmd->pdata[0] < 1) 672 fail = 1; 673 else 674 memcpy(cmd->info.data, &cmd->pdata[1], 675 cmd->info.datalen); 676 } 677 678 DPRINTK("SMU: completing, success: %d\n", !fail); 679 680 /* Update status and mark no pending i2c command with lock 681 * held so nobody comes in while we dequeue an eventual 682 * pending next i2c command 683 */ 684 spin_lock_irqsave(&smu->lock, flags); 685 smu->cmd_i2c_cur = NULL; 686 wmb(); 687 cmd->status = fail ? -EIO : 0; 688 689 /* Is there another i2c command waiting ? */ 690 if (!list_empty(&smu->cmd_i2c_list)) { 691 struct smu_i2c_cmd *newcmd; 692 693 /* Fetch it, new current, remove from list */ 694 newcmd = list_entry(smu->cmd_i2c_list.next, 695 struct smu_i2c_cmd, link); 696 smu->cmd_i2c_cur = newcmd; 697 list_del(&cmd->link); 698 699 /* Queue with low level smu */ 700 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 701 if (smu->cmd_cur == NULL) 702 smu_start_cmd(); 703 } 704 spin_unlock_irqrestore(&smu->lock, flags); 705 706 /* Call command completion handler if any */ 707 if (done) 708 done(cmd, misc); 709 710 } 711 712 713 static void smu_i2c_retry(unsigned long data) 714 { 715 struct smu_i2c_cmd *cmd = (struct smu_i2c_cmd *)data; 716 717 DPRINTK("SMU: i2c failure, requeuing...\n"); 718 719 /* requeue command simply by resetting reply_len */ 720 cmd->pdata[0] = 0xff; 721 cmd->scmd.reply_len = 0x10; 722 smu_queue_cmd(&cmd->scmd); 723 } 724 725 726 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 727 { 728 struct smu_i2c_cmd *cmd = misc; 729 int fail = 0; 730 731 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 732 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 733 734 /* Check for possible status */ 735 if (scmd->status < 0) 736 fail = 1; 737 else if (cmd->read) { 738 if (cmd->stage == 0) 739 fail = cmd->pdata[0] != 0; 740 else 741 fail = cmd->pdata[0] >= 0x80; 742 } else { 743 fail = cmd->pdata[0] != 0; 744 } 745 746 /* Handle failures by requeuing command, after 5ms interval 747 */ 748 if (fail && --cmd->retries > 0) { 749 DPRINTK("SMU: i2c failure, starting timer...\n"); 750 smu->i2c_timer.function = smu_i2c_retry; 751 smu->i2c_timer.data = (unsigned long)cmd; 752 smu->i2c_timer.expires = jiffies + msecs_to_jiffies(5); 753 add_timer(&smu->i2c_timer); 754 return; 755 } 756 757 /* If failure or stage 1, command is complete */ 758 if (fail || cmd->stage != 0) { 759 smu_i2c_complete_command(cmd, fail); 760 return; 761 } 762 763 DPRINTK("SMU: going to stage 1\n"); 764 765 /* Ok, initial command complete, now poll status */ 766 scmd->reply_buf = cmd->pdata; 767 scmd->reply_len = 0x10; 768 scmd->data_buf = cmd->pdata; 769 scmd->data_len = 1; 770 cmd->pdata[0] = 0; 771 cmd->stage = 1; 772 cmd->retries = 20; 773 smu_queue_cmd(scmd); 774 } 775 776 777 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 778 { 779 unsigned long flags; 780 781 if (smu == NULL) 782 return -ENODEV; 783 784 /* Fill most fields of scmd */ 785 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 786 cmd->scmd.done = smu_i2c_low_completion; 787 cmd->scmd.misc = cmd; 788 cmd->scmd.reply_buf = cmd->pdata; 789 cmd->scmd.reply_len = 0x10; 790 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 791 cmd->scmd.status = 1; 792 cmd->stage = 0; 793 cmd->pdata[0] = 0xff; 794 cmd->retries = 20; 795 cmd->status = 1; 796 797 /* Check transfer type, sanitize some "info" fields 798 * based on transfer type and do more checking 799 */ 800 cmd->info.caddr = cmd->info.devaddr; 801 cmd->read = cmd->info.devaddr & 0x01; 802 switch(cmd->info.type) { 803 case SMU_I2C_TRANSFER_SIMPLE: 804 memset(&cmd->info.sublen, 0, 4); 805 break; 806 case SMU_I2C_TRANSFER_COMBINED: 807 cmd->info.devaddr &= 0xfe; 808 case SMU_I2C_TRANSFER_STDSUB: 809 if (cmd->info.sublen > 3) 810 return -EINVAL; 811 break; 812 default: 813 return -EINVAL; 814 } 815 816 /* Finish setting up command based on transfer direction 817 */ 818 if (cmd->read) { 819 if (cmd->info.datalen > SMU_I2C_READ_MAX) 820 return -EINVAL; 821 memset(cmd->info.data, 0xff, cmd->info.datalen); 822 cmd->scmd.data_len = 9; 823 } else { 824 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 825 return -EINVAL; 826 cmd->scmd.data_len = 9 + cmd->info.datalen; 827 } 828 829 DPRINTK("SMU: i2c enqueuing command\n"); 830 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 831 cmd->read ? "read" : "write", cmd->info.datalen, 832 cmd->info.bus, cmd->info.caddr, 833 cmd->info.subaddr[0], cmd->info.type); 834 835 836 /* Enqueue command in i2c list, and if empty, enqueue also in 837 * main command list 838 */ 839 spin_lock_irqsave(&smu->lock, flags); 840 if (smu->cmd_i2c_cur == NULL) { 841 smu->cmd_i2c_cur = cmd; 842 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 843 if (smu->cmd_cur == NULL) 844 smu_start_cmd(); 845 } else 846 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 847 spin_unlock_irqrestore(&smu->lock, flags); 848 849 return 0; 850 } 851 852 /* 853 * Handling of "partitions" 854 */ 855 856 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 857 { 858 DECLARE_COMPLETION(comp); 859 unsigned int chunk; 860 struct smu_cmd cmd; 861 int rc; 862 u8 params[8]; 863 864 /* We currently use a chunk size of 0xe. We could check the 865 * SMU firmware version and use bigger sizes though 866 */ 867 chunk = 0xe; 868 869 while (len) { 870 unsigned int clen = min(len, chunk); 871 872 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 873 cmd.data_len = 7; 874 cmd.data_buf = params; 875 cmd.reply_len = chunk; 876 cmd.reply_buf = dest; 877 cmd.done = smu_done_complete; 878 cmd.misc = ∁ 879 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 880 params[1] = 0x4; 881 *((u32 *)¶ms[2]) = addr; 882 params[6] = clen; 883 884 rc = smu_queue_cmd(&cmd); 885 if (rc) 886 return rc; 887 wait_for_completion(&comp); 888 if (cmd.status != 0) 889 return rc; 890 if (cmd.reply_len != clen) { 891 printk(KERN_DEBUG "SMU: short read in " 892 "smu_read_datablock, got: %d, want: %d\n", 893 cmd.reply_len, clen); 894 return -EIO; 895 } 896 len -= clen; 897 addr += clen; 898 dest += clen; 899 } 900 return 0; 901 } 902 903 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 904 { 905 DECLARE_COMPLETION(comp); 906 struct smu_simple_cmd cmd; 907 unsigned int addr, len, tlen; 908 struct smu_sdbp_header *hdr; 909 struct property *prop; 910 911 /* First query the partition info */ 912 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 913 smu_done_complete, &comp, 914 SMU_CMD_PARTITION_LATEST, id); 915 wait_for_completion(&comp); 916 917 /* Partition doesn't exist (or other error) */ 918 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 919 return NULL; 920 921 /* Fetch address and length from reply */ 922 addr = *((u16 *)cmd.buffer); 923 len = cmd.buffer[3] << 2; 924 /* Calucluate total length to allocate, including the 17 bytes 925 * for "sdb-partition-XX" that we append at the end of the buffer 926 */ 927 tlen = sizeof(struct property) + len + 18; 928 929 prop = kcalloc(tlen, 1, GFP_KERNEL); 930 if (prop == NULL) 931 return NULL; 932 hdr = (struct smu_sdbp_header *)(prop + 1); 933 prop->name = ((char *)prop) + tlen - 18; 934 sprintf(prop->name, "sdb-partition-%02x", id); 935 prop->length = len; 936 prop->value = (unsigned char *)hdr; 937 prop->next = NULL; 938 939 /* Read the datablock */ 940 if (smu_read_datablock((u8 *)hdr, addr, len)) { 941 printk(KERN_DEBUG "SMU: datablock read failed while reading " 942 "partition %02x !\n", id); 943 goto failure; 944 } 945 946 /* Got it, check a few things and create the property */ 947 if (hdr->id != id) { 948 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 949 "%02x !\n", id, hdr->id); 950 goto failure; 951 } 952 if (prom_add_property(smu->of_node, prop)) { 953 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 954 "property !\n", id); 955 goto failure; 956 } 957 958 return hdr; 959 failure: 960 kfree(prop); 961 return NULL; 962 } 963 964 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 965 * when interruptible is 1 966 */ 967 struct smu_sdbp_header *__smu_get_sdb_partition(int id, unsigned int *size, 968 int interruptible) 969 { 970 char pname[32]; 971 struct smu_sdbp_header *part; 972 973 if (!smu) 974 return NULL; 975 976 sprintf(pname, "sdb-partition-%02x", id); 977 978 if (interruptible) { 979 int rc; 980 rc = down_interruptible(&smu_part_access); 981 if (rc) 982 return ERR_PTR(rc); 983 } else 984 down(&smu_part_access); 985 986 part = (struct smu_sdbp_header *)get_property(smu->of_node, 987 pname, size); 988 if (part == NULL) { 989 part = smu_create_sdb_partition(id); 990 if (part != NULL && size) 991 *size = part->len << 2; 992 } 993 up(&smu_part_access); 994 return part; 995 } 996 997 struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 998 { 999 return __smu_get_sdb_partition(id, size, 0); 1000 } 1001 EXPORT_SYMBOL(smu_get_sdb_partition); 1002 1003 1004 /* 1005 * Userland driver interface 1006 */ 1007 1008 1009 static LIST_HEAD(smu_clist); 1010 static DEFINE_SPINLOCK(smu_clist_lock); 1011 1012 enum smu_file_mode { 1013 smu_file_commands, 1014 smu_file_events, 1015 smu_file_closing 1016 }; 1017 1018 struct smu_private 1019 { 1020 struct list_head list; 1021 enum smu_file_mode mode; 1022 int busy; 1023 struct smu_cmd cmd; 1024 spinlock_t lock; 1025 wait_queue_head_t wait; 1026 u8 buffer[SMU_MAX_DATA]; 1027 }; 1028 1029 1030 static int smu_open(struct inode *inode, struct file *file) 1031 { 1032 struct smu_private *pp; 1033 unsigned long flags; 1034 1035 pp = kmalloc(sizeof(struct smu_private), GFP_KERNEL); 1036 if (pp == 0) 1037 return -ENOMEM; 1038 memset(pp, 0, sizeof(struct smu_private)); 1039 spin_lock_init(&pp->lock); 1040 pp->mode = smu_file_commands; 1041 init_waitqueue_head(&pp->wait); 1042 1043 spin_lock_irqsave(&smu_clist_lock, flags); 1044 list_add(&pp->list, &smu_clist); 1045 spin_unlock_irqrestore(&smu_clist_lock, flags); 1046 file->private_data = pp; 1047 1048 return 0; 1049 } 1050 1051 1052 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1053 { 1054 struct smu_private *pp = misc; 1055 1056 wake_up_all(&pp->wait); 1057 } 1058 1059 1060 static ssize_t smu_write(struct file *file, const char __user *buf, 1061 size_t count, loff_t *ppos) 1062 { 1063 struct smu_private *pp = file->private_data; 1064 unsigned long flags; 1065 struct smu_user_cmd_hdr hdr; 1066 int rc = 0; 1067 1068 if (pp->busy) 1069 return -EBUSY; 1070 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1071 return -EFAULT; 1072 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1073 pp->mode = smu_file_events; 1074 return 0; 1075 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1076 struct smu_sdbp_header *part; 1077 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1078 if (part == NULL) 1079 return -EINVAL; 1080 else if (IS_ERR(part)) 1081 return PTR_ERR(part); 1082 return 0; 1083 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1084 return -EINVAL; 1085 else if (pp->mode != smu_file_commands) 1086 return -EBADFD; 1087 else if (hdr.data_len > SMU_MAX_DATA) 1088 return -EINVAL; 1089 1090 spin_lock_irqsave(&pp->lock, flags); 1091 if (pp->busy) { 1092 spin_unlock_irqrestore(&pp->lock, flags); 1093 return -EBUSY; 1094 } 1095 pp->busy = 1; 1096 pp->cmd.status = 1; 1097 spin_unlock_irqrestore(&pp->lock, flags); 1098 1099 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1100 pp->busy = 0; 1101 return -EFAULT; 1102 } 1103 1104 pp->cmd.cmd = hdr.cmd; 1105 pp->cmd.data_len = hdr.data_len; 1106 pp->cmd.reply_len = SMU_MAX_DATA; 1107 pp->cmd.data_buf = pp->buffer; 1108 pp->cmd.reply_buf = pp->buffer; 1109 pp->cmd.done = smu_user_cmd_done; 1110 pp->cmd.misc = pp; 1111 rc = smu_queue_cmd(&pp->cmd); 1112 if (rc < 0) 1113 return rc; 1114 return count; 1115 } 1116 1117 1118 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1119 char __user *buf, size_t count) 1120 { 1121 DECLARE_WAITQUEUE(wait, current); 1122 struct smu_user_reply_hdr hdr; 1123 unsigned long flags; 1124 int size, rc = 0; 1125 1126 if (!pp->busy) 1127 return 0; 1128 if (count < sizeof(struct smu_user_reply_hdr)) 1129 return -EOVERFLOW; 1130 spin_lock_irqsave(&pp->lock, flags); 1131 if (pp->cmd.status == 1) { 1132 if (file->f_flags & O_NONBLOCK) 1133 return -EAGAIN; 1134 add_wait_queue(&pp->wait, &wait); 1135 for (;;) { 1136 set_current_state(TASK_INTERRUPTIBLE); 1137 rc = 0; 1138 if (pp->cmd.status != 1) 1139 break; 1140 rc = -ERESTARTSYS; 1141 if (signal_pending(current)) 1142 break; 1143 spin_unlock_irqrestore(&pp->lock, flags); 1144 schedule(); 1145 spin_lock_irqsave(&pp->lock, flags); 1146 } 1147 set_current_state(TASK_RUNNING); 1148 remove_wait_queue(&pp->wait, &wait); 1149 } 1150 spin_unlock_irqrestore(&pp->lock, flags); 1151 if (rc) 1152 return rc; 1153 if (pp->cmd.status != 0) 1154 pp->cmd.reply_len = 0; 1155 size = sizeof(hdr) + pp->cmd.reply_len; 1156 if (count < size) 1157 size = count; 1158 rc = size; 1159 hdr.status = pp->cmd.status; 1160 hdr.reply_len = pp->cmd.reply_len; 1161 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1162 return -EFAULT; 1163 size -= sizeof(hdr); 1164 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1165 return -EFAULT; 1166 pp->busy = 0; 1167 1168 return rc; 1169 } 1170 1171 1172 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1173 char __user *buf, size_t count) 1174 { 1175 /* Not implemented */ 1176 msleep_interruptible(1000); 1177 return 0; 1178 } 1179 1180 1181 static ssize_t smu_read(struct file *file, char __user *buf, 1182 size_t count, loff_t *ppos) 1183 { 1184 struct smu_private *pp = file->private_data; 1185 1186 if (pp->mode == smu_file_commands) 1187 return smu_read_command(file, pp, buf, count); 1188 if (pp->mode == smu_file_events) 1189 return smu_read_events(file, pp, buf, count); 1190 1191 return -EBADFD; 1192 } 1193 1194 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1195 { 1196 struct smu_private *pp = file->private_data; 1197 unsigned int mask = 0; 1198 unsigned long flags; 1199 1200 if (pp == 0) 1201 return 0; 1202 1203 if (pp->mode == smu_file_commands) { 1204 poll_wait(file, &pp->wait, wait); 1205 1206 spin_lock_irqsave(&pp->lock, flags); 1207 if (pp->busy && pp->cmd.status != 1) 1208 mask |= POLLIN; 1209 spin_unlock_irqrestore(&pp->lock, flags); 1210 } if (pp->mode == smu_file_events) { 1211 /* Not yet implemented */ 1212 } 1213 return mask; 1214 } 1215 1216 static int smu_release(struct inode *inode, struct file *file) 1217 { 1218 struct smu_private *pp = file->private_data; 1219 unsigned long flags; 1220 unsigned int busy; 1221 1222 if (pp == 0) 1223 return 0; 1224 1225 file->private_data = NULL; 1226 1227 /* Mark file as closing to avoid races with new request */ 1228 spin_lock_irqsave(&pp->lock, flags); 1229 pp->mode = smu_file_closing; 1230 busy = pp->busy; 1231 1232 /* Wait for any pending request to complete */ 1233 if (busy && pp->cmd.status == 1) { 1234 DECLARE_WAITQUEUE(wait, current); 1235 1236 add_wait_queue(&pp->wait, &wait); 1237 for (;;) { 1238 set_current_state(TASK_UNINTERRUPTIBLE); 1239 if (pp->cmd.status != 1) 1240 break; 1241 spin_lock_irqsave(&pp->lock, flags); 1242 schedule(); 1243 spin_unlock_irqrestore(&pp->lock, flags); 1244 } 1245 set_current_state(TASK_RUNNING); 1246 remove_wait_queue(&pp->wait, &wait); 1247 } 1248 spin_unlock_irqrestore(&pp->lock, flags); 1249 1250 spin_lock_irqsave(&smu_clist_lock, flags); 1251 list_del(&pp->list); 1252 spin_unlock_irqrestore(&smu_clist_lock, flags); 1253 kfree(pp); 1254 1255 return 0; 1256 } 1257 1258 1259 static struct file_operations smu_device_fops = { 1260 .llseek = no_llseek, 1261 .read = smu_read, 1262 .write = smu_write, 1263 .poll = smu_fpoll, 1264 .open = smu_open, 1265 .release = smu_release, 1266 }; 1267 1268 static struct miscdevice pmu_device = { 1269 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1270 }; 1271 1272 static int smu_device_init(void) 1273 { 1274 if (!smu) 1275 return -ENODEV; 1276 if (misc_register(&pmu_device) < 0) 1277 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1278 return 0; 1279 } 1280 device_initcall(smu_device_init); 1281