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 #include <linux/mutex.h> 39 40 #include <asm/byteorder.h> 41 #include <asm/io.h> 42 #include <asm/prom.h> 43 #include <asm/machdep.h> 44 #include <asm/pmac_feature.h> 45 #include <asm/smu.h> 46 #include <asm/sections.h> 47 #include <asm/abs_addr.h> 48 #include <asm/uaccess.h> 49 #include <asm/of_device.h> 50 51 #define VERSION "0.7" 52 #define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp." 53 54 #undef DEBUG_SMU 55 56 #ifdef DEBUG_SMU 57 #define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0) 58 #else 59 #define DPRINTK(fmt, args...) do { } while (0) 60 #endif 61 62 /* 63 * This is the command buffer passed to the SMU hardware 64 */ 65 #define SMU_MAX_DATA 254 66 67 struct smu_cmd_buf { 68 u8 cmd; 69 u8 length; 70 u8 data[SMU_MAX_DATA]; 71 }; 72 73 struct smu_device { 74 spinlock_t lock; 75 struct device_node *of_node; 76 struct of_device *of_dev; 77 int doorbell; /* doorbell gpio */ 78 u32 __iomem *db_buf; /* doorbell buffer */ 79 int db_irq; 80 int msg; 81 int msg_irq; 82 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ 83 u32 cmd_buf_abs; /* command buffer absolute */ 84 struct list_head cmd_list; 85 struct smu_cmd *cmd_cur; /* pending command */ 86 struct list_head cmd_i2c_list; 87 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 88 struct timer_list i2c_timer; 89 }; 90 91 /* 92 * I don't think there will ever be more than one SMU, so 93 * for now, just hard code that 94 */ 95 static struct smu_device *smu; 96 static DEFINE_MUTEX(smu_part_access); 97 98 static void smu_i2c_retry(unsigned long data); 99 100 /* 101 * SMU driver low level stuff 102 */ 103 104 static void smu_start_cmd(void) 105 { 106 unsigned long faddr, fend; 107 struct smu_cmd *cmd; 108 109 if (list_empty(&smu->cmd_list)) 110 return; 111 112 /* Fetch first command in queue */ 113 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 114 smu->cmd_cur = cmd; 115 list_del(&cmd->link); 116 117 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 118 cmd->data_len); 119 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 120 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 121 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 122 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 123 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 124 125 /* Fill the SMU command buffer */ 126 smu->cmd_buf->cmd = cmd->cmd; 127 smu->cmd_buf->length = cmd->data_len; 128 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 129 130 /* Flush command and data to RAM */ 131 faddr = (unsigned long)smu->cmd_buf; 132 fend = faddr + smu->cmd_buf->length + 2; 133 flush_inval_dcache_range(faddr, fend); 134 135 /* This isn't exactly a DMA mapping here, I suspect 136 * the SMU is actually communicating with us via i2c to the 137 * northbridge or the CPU to access RAM. 138 */ 139 writel(smu->cmd_buf_abs, smu->db_buf); 140 141 /* Ring the SMU doorbell */ 142 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 143 } 144 145 146 static irqreturn_t smu_db_intr(int irq, void *arg, struct pt_regs *regs) 147 { 148 unsigned long flags; 149 struct smu_cmd *cmd; 150 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 151 void *misc = NULL; 152 u8 gpio; 153 int rc = 0; 154 155 /* SMU completed the command, well, we hope, let's make sure 156 * of it 157 */ 158 spin_lock_irqsave(&smu->lock, flags); 159 160 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 161 if ((gpio & 7) != 7) { 162 spin_unlock_irqrestore(&smu->lock, flags); 163 return IRQ_HANDLED; 164 } 165 166 cmd = smu->cmd_cur; 167 smu->cmd_cur = NULL; 168 if (cmd == NULL) 169 goto bail; 170 171 if (rc == 0) { 172 unsigned long faddr; 173 int reply_len; 174 u8 ack; 175 176 /* CPU might have brought back the cache line, so we need 177 * to flush again before peeking at the SMU response. We 178 * flush the entire buffer for now as we haven't read the 179 * reply lenght (it's only 2 cache lines anyway) 180 */ 181 faddr = (unsigned long)smu->cmd_buf; 182 flush_inval_dcache_range(faddr, faddr + 256); 183 184 /* Now check ack */ 185 ack = (~cmd->cmd) & 0xff; 186 if (ack != smu->cmd_buf->cmd) { 187 DPRINTK("SMU: incorrect ack, want %x got %x\n", 188 ack, smu->cmd_buf->cmd); 189 rc = -EIO; 190 } 191 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 192 DPRINTK("SMU: reply len: %d\n", reply_len); 193 if (reply_len > cmd->reply_len) { 194 printk(KERN_WARNING "SMU: reply buffer too small," 195 "got %d bytes for a %d bytes buffer\n", 196 reply_len, cmd->reply_len); 197 reply_len = cmd->reply_len; 198 } 199 cmd->reply_len = reply_len; 200 if (cmd->reply_buf && reply_len) 201 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 202 } 203 204 /* Now complete the command. Write status last in order as we lost 205 * ownership of the command structure as soon as it's no longer -1 206 */ 207 done = cmd->done; 208 misc = cmd->misc; 209 mb(); 210 cmd->status = rc; 211 bail: 212 /* Start next command if any */ 213 smu_start_cmd(); 214 spin_unlock_irqrestore(&smu->lock, flags); 215 216 /* Call command completion handler if any */ 217 if (done) 218 done(cmd, misc); 219 220 /* It's an edge interrupt, nothing to do */ 221 return IRQ_HANDLED; 222 } 223 224 225 static irqreturn_t smu_msg_intr(int irq, void *arg, struct pt_regs *regs) 226 { 227 /* I don't quite know what to do with this one, we seem to never 228 * receive it, so I suspect we have to arm it someway in the SMU 229 * to start getting events that way. 230 */ 231 232 printk(KERN_INFO "SMU: message interrupt !\n"); 233 234 /* It's an edge interrupt, nothing to do */ 235 return IRQ_HANDLED; 236 } 237 238 239 /* 240 * Queued command management. 241 * 242 */ 243 244 int smu_queue_cmd(struct smu_cmd *cmd) 245 { 246 unsigned long flags; 247 248 if (smu == NULL) 249 return -ENODEV; 250 if (cmd->data_len > SMU_MAX_DATA || 251 cmd->reply_len > SMU_MAX_DATA) 252 return -EINVAL; 253 254 cmd->status = 1; 255 spin_lock_irqsave(&smu->lock, flags); 256 list_add_tail(&cmd->link, &smu->cmd_list); 257 if (smu->cmd_cur == NULL) 258 smu_start_cmd(); 259 spin_unlock_irqrestore(&smu->lock, flags); 260 261 return 0; 262 } 263 EXPORT_SYMBOL(smu_queue_cmd); 264 265 266 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 267 unsigned int data_len, 268 void (*done)(struct smu_cmd *cmd, void *misc), 269 void *misc, ...) 270 { 271 struct smu_cmd *cmd = &scmd->cmd; 272 va_list list; 273 int i; 274 275 if (data_len > sizeof(scmd->buffer)) 276 return -EINVAL; 277 278 memset(scmd, 0, sizeof(*scmd)); 279 cmd->cmd = command; 280 cmd->data_len = data_len; 281 cmd->data_buf = scmd->buffer; 282 cmd->reply_len = sizeof(scmd->buffer); 283 cmd->reply_buf = scmd->buffer; 284 cmd->done = done; 285 cmd->misc = misc; 286 287 va_start(list, misc); 288 for (i = 0; i < data_len; ++i) 289 scmd->buffer[i] = (u8)va_arg(list, int); 290 va_end(list); 291 292 return smu_queue_cmd(cmd); 293 } 294 EXPORT_SYMBOL(smu_queue_simple); 295 296 297 void smu_poll(void) 298 { 299 u8 gpio; 300 301 if (smu == NULL) 302 return; 303 304 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 305 if ((gpio & 7) == 7) 306 smu_db_intr(smu->db_irq, smu, NULL); 307 } 308 EXPORT_SYMBOL(smu_poll); 309 310 311 void smu_done_complete(struct smu_cmd *cmd, void *misc) 312 { 313 struct completion *comp = misc; 314 315 complete(comp); 316 } 317 EXPORT_SYMBOL(smu_done_complete); 318 319 320 void smu_spinwait_cmd(struct smu_cmd *cmd) 321 { 322 while(cmd->status == 1) 323 smu_poll(); 324 } 325 EXPORT_SYMBOL(smu_spinwait_cmd); 326 327 328 /* RTC low level commands */ 329 static inline int bcd2hex (int n) 330 { 331 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 332 } 333 334 335 static inline int hex2bcd (int n) 336 { 337 return ((n / 10) << 4) + (n % 10); 338 } 339 340 341 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 342 struct rtc_time *time) 343 { 344 cmd_buf->cmd = 0x8e; 345 cmd_buf->length = 8; 346 cmd_buf->data[0] = 0x80; 347 cmd_buf->data[1] = hex2bcd(time->tm_sec); 348 cmd_buf->data[2] = hex2bcd(time->tm_min); 349 cmd_buf->data[3] = hex2bcd(time->tm_hour); 350 cmd_buf->data[4] = time->tm_wday; 351 cmd_buf->data[5] = hex2bcd(time->tm_mday); 352 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 353 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 354 } 355 356 357 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 358 { 359 struct smu_simple_cmd cmd; 360 int rc; 361 362 if (smu == NULL) 363 return -ENODEV; 364 365 memset(time, 0, sizeof(struct rtc_time)); 366 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 367 SMU_CMD_RTC_GET_DATETIME); 368 if (rc) 369 return rc; 370 smu_spinwait_simple(&cmd); 371 372 time->tm_sec = bcd2hex(cmd.buffer[0]); 373 time->tm_min = bcd2hex(cmd.buffer[1]); 374 time->tm_hour = bcd2hex(cmd.buffer[2]); 375 time->tm_wday = bcd2hex(cmd.buffer[3]); 376 time->tm_mday = bcd2hex(cmd.buffer[4]); 377 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 378 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 379 380 return 0; 381 } 382 383 384 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 385 { 386 struct smu_simple_cmd cmd; 387 int rc; 388 389 if (smu == NULL) 390 return -ENODEV; 391 392 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 393 SMU_CMD_RTC_SET_DATETIME, 394 hex2bcd(time->tm_sec), 395 hex2bcd(time->tm_min), 396 hex2bcd(time->tm_hour), 397 time->tm_wday, 398 hex2bcd(time->tm_mday), 399 hex2bcd(time->tm_mon) + 1, 400 hex2bcd(time->tm_year - 100)); 401 if (rc) 402 return rc; 403 smu_spinwait_simple(&cmd); 404 405 return 0; 406 } 407 408 409 void smu_shutdown(void) 410 { 411 struct smu_simple_cmd cmd; 412 413 if (smu == NULL) 414 return; 415 416 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 417 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 418 return; 419 smu_spinwait_simple(&cmd); 420 for (;;) 421 ; 422 } 423 424 425 void smu_restart(void) 426 { 427 struct smu_simple_cmd cmd; 428 429 if (smu == NULL) 430 return; 431 432 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 433 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 434 return; 435 smu_spinwait_simple(&cmd); 436 for (;;) 437 ; 438 } 439 440 441 int smu_present(void) 442 { 443 return smu != NULL; 444 } 445 EXPORT_SYMBOL(smu_present); 446 447 448 int __init smu_init (void) 449 { 450 struct device_node *np; 451 u32 *data; 452 453 np = of_find_node_by_type(NULL, "smu"); 454 if (np == NULL) 455 return -ENODEV; 456 457 printk(KERN_INFO "SMU driver %s %s\n", VERSION, AUTHOR); 458 459 if (smu_cmdbuf_abs == 0) { 460 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 461 return -EINVAL; 462 } 463 464 smu = alloc_bootmem(sizeof(struct smu_device)); 465 if (smu == NULL) 466 return -ENOMEM; 467 memset(smu, 0, sizeof(*smu)); 468 469 spin_lock_init(&smu->lock); 470 INIT_LIST_HEAD(&smu->cmd_list); 471 INIT_LIST_HEAD(&smu->cmd_i2c_list); 472 smu->of_node = np; 473 smu->db_irq = NO_IRQ; 474 smu->msg_irq = NO_IRQ; 475 476 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 477 * 32 bits value safely 478 */ 479 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 480 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); 481 482 np = of_find_node_by_name(NULL, "smu-doorbell"); 483 if (np == NULL) { 484 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 485 goto fail; 486 } 487 data = (u32 *)get_property(np, "reg", NULL); 488 if (data == NULL) { 489 of_node_put(np); 490 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 491 goto fail; 492 } 493 494 /* Current setup has one doorbell GPIO that does both doorbell 495 * and ack. GPIOs are at 0x50, best would be to find that out 496 * in the device-tree though. 497 */ 498 smu->doorbell = *data; 499 if (smu->doorbell < 0x50) 500 smu->doorbell += 0x50; 501 if (np->n_intrs > 0) 502 smu->db_irq = np->intrs[0].line; 503 504 of_node_put(np); 505 506 /* Now look for the smu-interrupt GPIO */ 507 do { 508 np = of_find_node_by_name(NULL, "smu-interrupt"); 509 if (np == NULL) 510 break; 511 data = (u32 *)get_property(np, "reg", NULL); 512 if (data == NULL) { 513 of_node_put(np); 514 break; 515 } 516 smu->msg = *data; 517 if (smu->msg < 0x50) 518 smu->msg += 0x50; 519 if (np->n_intrs > 0) 520 smu->msg_irq = np->intrs[0].line; 521 of_node_put(np); 522 } while(0); 523 524 /* Doorbell buffer is currently hard-coded, I didn't find a proper 525 * device-tree entry giving the address. Best would probably to use 526 * an offset for K2 base though, but let's do it that way for now. 527 */ 528 smu->db_buf = ioremap(0x8000860c, 0x1000); 529 if (smu->db_buf == NULL) { 530 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 531 goto fail; 532 } 533 534 sys_ctrler = SYS_CTRLER_SMU; 535 return 0; 536 537 fail: 538 smu = NULL; 539 return -ENXIO; 540 541 } 542 543 544 static int smu_late_init(void) 545 { 546 if (!smu) 547 return 0; 548 549 init_timer(&smu->i2c_timer); 550 smu->i2c_timer.function = smu_i2c_retry; 551 smu->i2c_timer.data = (unsigned long)smu; 552 553 /* 554 * Try to request the interrupts 555 */ 556 557 if (smu->db_irq != NO_IRQ) { 558 if (request_irq(smu->db_irq, smu_db_intr, 559 SA_SHIRQ, "SMU doorbell", smu) < 0) { 560 printk(KERN_WARNING "SMU: can't " 561 "request interrupt %d\n", 562 smu->db_irq); 563 smu->db_irq = NO_IRQ; 564 } 565 } 566 567 if (smu->msg_irq != NO_IRQ) { 568 if (request_irq(smu->msg_irq, smu_msg_intr, 569 SA_SHIRQ, "SMU message", smu) < 0) { 570 printk(KERN_WARNING "SMU: can't " 571 "request interrupt %d\n", 572 smu->msg_irq); 573 smu->msg_irq = NO_IRQ; 574 } 575 } 576 577 return 0; 578 } 579 /* This has to be before arch_initcall as the low i2c stuff relies on the 580 * above having been done before we reach arch_initcalls 581 */ 582 core_initcall(smu_late_init); 583 584 /* 585 * sysfs visibility 586 */ 587 588 static void smu_expose_childs(void *unused) 589 { 590 struct device_node *np; 591 592 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 593 if (device_is_compatible(np, "smu-sensors")) 594 of_platform_device_create(np, "smu-sensors", 595 &smu->of_dev->dev); 596 } 597 598 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs, NULL); 599 600 static int smu_platform_probe(struct of_device* dev, 601 const struct of_device_id *match) 602 { 603 if (!smu) 604 return -ENODEV; 605 smu->of_dev = dev; 606 607 /* 608 * Ok, we are matched, now expose all i2c busses. We have to defer 609 * that unfortunately or it would deadlock inside the device model 610 */ 611 schedule_work(&smu_expose_childs_work); 612 613 return 0; 614 } 615 616 static struct of_device_id smu_platform_match[] = 617 { 618 { 619 .type = "smu", 620 }, 621 {}, 622 }; 623 624 static struct of_platform_driver smu_of_platform_driver = 625 { 626 .name = "smu", 627 .match_table = smu_platform_match, 628 .probe = smu_platform_probe, 629 }; 630 631 static int __init smu_init_sysfs(void) 632 { 633 /* 634 * Due to sysfs bogosity, a sysdev is not a real device, so 635 * we should in fact create both if we want sysdev semantics 636 * for power management. 637 * For now, we don't power manage machines with an SMU chip, 638 * I'm a bit too far from figuring out how that works with those 639 * new chipsets, but that will come back and bite us 640 */ 641 of_register_driver(&smu_of_platform_driver); 642 return 0; 643 } 644 645 device_initcall(smu_init_sysfs); 646 647 struct of_device *smu_get_ofdev(void) 648 { 649 if (!smu) 650 return NULL; 651 return smu->of_dev; 652 } 653 654 EXPORT_SYMBOL_GPL(smu_get_ofdev); 655 656 /* 657 * i2c interface 658 */ 659 660 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 661 { 662 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 663 void *misc = cmd->misc; 664 unsigned long flags; 665 666 /* Check for read case */ 667 if (!fail && cmd->read) { 668 if (cmd->pdata[0] < 1) 669 fail = 1; 670 else 671 memcpy(cmd->info.data, &cmd->pdata[1], 672 cmd->info.datalen); 673 } 674 675 DPRINTK("SMU: completing, success: %d\n", !fail); 676 677 /* Update status and mark no pending i2c command with lock 678 * held so nobody comes in while we dequeue an eventual 679 * pending next i2c command 680 */ 681 spin_lock_irqsave(&smu->lock, flags); 682 smu->cmd_i2c_cur = NULL; 683 wmb(); 684 cmd->status = fail ? -EIO : 0; 685 686 /* Is there another i2c command waiting ? */ 687 if (!list_empty(&smu->cmd_i2c_list)) { 688 struct smu_i2c_cmd *newcmd; 689 690 /* Fetch it, new current, remove from list */ 691 newcmd = list_entry(smu->cmd_i2c_list.next, 692 struct smu_i2c_cmd, link); 693 smu->cmd_i2c_cur = newcmd; 694 list_del(&cmd->link); 695 696 /* Queue with low level smu */ 697 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 698 if (smu->cmd_cur == NULL) 699 smu_start_cmd(); 700 } 701 spin_unlock_irqrestore(&smu->lock, flags); 702 703 /* Call command completion handler if any */ 704 if (done) 705 done(cmd, misc); 706 707 } 708 709 710 static void smu_i2c_retry(unsigned long data) 711 { 712 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 713 714 DPRINTK("SMU: i2c failure, requeuing...\n"); 715 716 /* requeue command simply by resetting reply_len */ 717 cmd->pdata[0] = 0xff; 718 cmd->scmd.reply_len = sizeof(cmd->pdata); 719 smu_queue_cmd(&cmd->scmd); 720 } 721 722 723 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 724 { 725 struct smu_i2c_cmd *cmd = misc; 726 int fail = 0; 727 728 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 729 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 730 731 /* Check for possible status */ 732 if (scmd->status < 0) 733 fail = 1; 734 else if (cmd->read) { 735 if (cmd->stage == 0) 736 fail = cmd->pdata[0] != 0; 737 else 738 fail = cmd->pdata[0] >= 0x80; 739 } else { 740 fail = cmd->pdata[0] != 0; 741 } 742 743 /* Handle failures by requeuing command, after 5ms interval 744 */ 745 if (fail && --cmd->retries > 0) { 746 DPRINTK("SMU: i2c failure, starting timer...\n"); 747 BUG_ON(cmd != smu->cmd_i2c_cur); 748 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 749 return; 750 } 751 752 /* If failure or stage 1, command is complete */ 753 if (fail || cmd->stage != 0) { 754 smu_i2c_complete_command(cmd, fail); 755 return; 756 } 757 758 DPRINTK("SMU: going to stage 1\n"); 759 760 /* Ok, initial command complete, now poll status */ 761 scmd->reply_buf = cmd->pdata; 762 scmd->reply_len = sizeof(cmd->pdata); 763 scmd->data_buf = cmd->pdata; 764 scmd->data_len = 1; 765 cmd->pdata[0] = 0; 766 cmd->stage = 1; 767 cmd->retries = 20; 768 smu_queue_cmd(scmd); 769 } 770 771 772 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 773 { 774 unsigned long flags; 775 776 if (smu == NULL) 777 return -ENODEV; 778 779 /* Fill most fields of scmd */ 780 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 781 cmd->scmd.done = smu_i2c_low_completion; 782 cmd->scmd.misc = cmd; 783 cmd->scmd.reply_buf = cmd->pdata; 784 cmd->scmd.reply_len = sizeof(cmd->pdata); 785 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 786 cmd->scmd.status = 1; 787 cmd->stage = 0; 788 cmd->pdata[0] = 0xff; 789 cmd->retries = 20; 790 cmd->status = 1; 791 792 /* Check transfer type, sanitize some "info" fields 793 * based on transfer type and do more checking 794 */ 795 cmd->info.caddr = cmd->info.devaddr; 796 cmd->read = cmd->info.devaddr & 0x01; 797 switch(cmd->info.type) { 798 case SMU_I2C_TRANSFER_SIMPLE: 799 memset(&cmd->info.sublen, 0, 4); 800 break; 801 case SMU_I2C_TRANSFER_COMBINED: 802 cmd->info.devaddr &= 0xfe; 803 case SMU_I2C_TRANSFER_STDSUB: 804 if (cmd->info.sublen > 3) 805 return -EINVAL; 806 break; 807 default: 808 return -EINVAL; 809 } 810 811 /* Finish setting up command based on transfer direction 812 */ 813 if (cmd->read) { 814 if (cmd->info.datalen > SMU_I2C_READ_MAX) 815 return -EINVAL; 816 memset(cmd->info.data, 0xff, cmd->info.datalen); 817 cmd->scmd.data_len = 9; 818 } else { 819 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 820 return -EINVAL; 821 cmd->scmd.data_len = 9 + cmd->info.datalen; 822 } 823 824 DPRINTK("SMU: i2c enqueuing command\n"); 825 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 826 cmd->read ? "read" : "write", cmd->info.datalen, 827 cmd->info.bus, cmd->info.caddr, 828 cmd->info.subaddr[0], cmd->info.type); 829 830 831 /* Enqueue command in i2c list, and if empty, enqueue also in 832 * main command list 833 */ 834 spin_lock_irqsave(&smu->lock, flags); 835 if (smu->cmd_i2c_cur == NULL) { 836 smu->cmd_i2c_cur = cmd; 837 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 838 if (smu->cmd_cur == NULL) 839 smu_start_cmd(); 840 } else 841 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 842 spin_unlock_irqrestore(&smu->lock, flags); 843 844 return 0; 845 } 846 847 /* 848 * Handling of "partitions" 849 */ 850 851 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 852 { 853 DECLARE_COMPLETION(comp); 854 unsigned int chunk; 855 struct smu_cmd cmd; 856 int rc; 857 u8 params[8]; 858 859 /* We currently use a chunk size of 0xe. We could check the 860 * SMU firmware version and use bigger sizes though 861 */ 862 chunk = 0xe; 863 864 while (len) { 865 unsigned int clen = min(len, chunk); 866 867 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 868 cmd.data_len = 7; 869 cmd.data_buf = params; 870 cmd.reply_len = chunk; 871 cmd.reply_buf = dest; 872 cmd.done = smu_done_complete; 873 cmd.misc = ∁ 874 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 875 params[1] = 0x4; 876 *((u32 *)¶ms[2]) = addr; 877 params[6] = clen; 878 879 rc = smu_queue_cmd(&cmd); 880 if (rc) 881 return rc; 882 wait_for_completion(&comp); 883 if (cmd.status != 0) 884 return rc; 885 if (cmd.reply_len != clen) { 886 printk(KERN_DEBUG "SMU: short read in " 887 "smu_read_datablock, got: %d, want: %d\n", 888 cmd.reply_len, clen); 889 return -EIO; 890 } 891 len -= clen; 892 addr += clen; 893 dest += clen; 894 } 895 return 0; 896 } 897 898 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 899 { 900 DECLARE_COMPLETION(comp); 901 struct smu_simple_cmd cmd; 902 unsigned int addr, len, tlen; 903 struct smu_sdbp_header *hdr; 904 struct property *prop; 905 906 /* First query the partition info */ 907 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 908 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 909 smu_done_complete, &comp, 910 SMU_CMD_PARTITION_LATEST, id); 911 wait_for_completion(&comp); 912 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 913 cmd.cmd.status, cmd.cmd.reply_len); 914 915 /* Partition doesn't exist (or other error) */ 916 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 917 return NULL; 918 919 /* Fetch address and length from reply */ 920 addr = *((u16 *)cmd.buffer); 921 len = cmd.buffer[3] << 2; 922 /* Calucluate total length to allocate, including the 17 bytes 923 * for "sdb-partition-XX" that we append at the end of the buffer 924 */ 925 tlen = sizeof(struct property) + len + 18; 926 927 prop = kcalloc(tlen, 1, GFP_KERNEL); 928 if (prop == NULL) 929 return NULL; 930 hdr = (struct smu_sdbp_header *)(prop + 1); 931 prop->name = ((char *)prop) + tlen - 18; 932 sprintf(prop->name, "sdb-partition-%02x", id); 933 prop->length = len; 934 prop->value = (unsigned char *)hdr; 935 prop->next = NULL; 936 937 /* Read the datablock */ 938 if (smu_read_datablock((u8 *)hdr, addr, len)) { 939 printk(KERN_DEBUG "SMU: datablock read failed while reading " 940 "partition %02x !\n", id); 941 goto failure; 942 } 943 944 /* Got it, check a few things and create the property */ 945 if (hdr->id != id) { 946 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 947 "%02x !\n", id, hdr->id); 948 goto failure; 949 } 950 if (prom_add_property(smu->of_node, prop)) { 951 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 952 "property !\n", id); 953 goto failure; 954 } 955 956 return hdr; 957 failure: 958 kfree(prop); 959 return NULL; 960 } 961 962 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 963 * when interruptible is 1 964 */ 965 struct smu_sdbp_header *__smu_get_sdb_partition(int id, unsigned int *size, 966 int interruptible) 967 { 968 char pname[32]; 969 struct smu_sdbp_header *part; 970 971 if (!smu) 972 return NULL; 973 974 sprintf(pname, "sdb-partition-%02x", id); 975 976 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 977 978 if (interruptible) { 979 int rc; 980 rc = mutex_lock_interruptible(&smu_part_access); 981 if (rc) 982 return ERR_PTR(rc); 983 } else 984 mutex_lock(&smu_part_access); 985 986 part = (struct smu_sdbp_header *)get_property(smu->of_node, 987 pname, size); 988 if (part == NULL) { 989 DPRINTK("trying to extract from SMU ...\n"); 990 part = smu_create_sdb_partition(id); 991 if (part != NULL && size) 992 *size = part->len << 2; 993 } 994 mutex_unlock(&smu_part_access); 995 return part; 996 } 997 998 struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 999 { 1000 return __smu_get_sdb_partition(id, size, 0); 1001 } 1002 EXPORT_SYMBOL(smu_get_sdb_partition); 1003 1004 1005 /* 1006 * Userland driver interface 1007 */ 1008 1009 1010 static LIST_HEAD(smu_clist); 1011 static DEFINE_SPINLOCK(smu_clist_lock); 1012 1013 enum smu_file_mode { 1014 smu_file_commands, 1015 smu_file_events, 1016 smu_file_closing 1017 }; 1018 1019 struct smu_private 1020 { 1021 struct list_head list; 1022 enum smu_file_mode mode; 1023 int busy; 1024 struct smu_cmd cmd; 1025 spinlock_t lock; 1026 wait_queue_head_t wait; 1027 u8 buffer[SMU_MAX_DATA]; 1028 }; 1029 1030 1031 static int smu_open(struct inode *inode, struct file *file) 1032 { 1033 struct smu_private *pp; 1034 unsigned long flags; 1035 1036 pp = kmalloc(sizeof(struct smu_private), GFP_KERNEL); 1037 if (pp == 0) 1038 return -ENOMEM; 1039 memset(pp, 0, sizeof(struct smu_private)); 1040 spin_lock_init(&pp->lock); 1041 pp->mode = smu_file_commands; 1042 init_waitqueue_head(&pp->wait); 1043 1044 spin_lock_irqsave(&smu_clist_lock, flags); 1045 list_add(&pp->list, &smu_clist); 1046 spin_unlock_irqrestore(&smu_clist_lock, flags); 1047 file->private_data = pp; 1048 1049 return 0; 1050 } 1051 1052 1053 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1054 { 1055 struct smu_private *pp = misc; 1056 1057 wake_up_all(&pp->wait); 1058 } 1059 1060 1061 static ssize_t smu_write(struct file *file, const char __user *buf, 1062 size_t count, loff_t *ppos) 1063 { 1064 struct smu_private *pp = file->private_data; 1065 unsigned long flags; 1066 struct smu_user_cmd_hdr hdr; 1067 int rc = 0; 1068 1069 if (pp->busy) 1070 return -EBUSY; 1071 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1072 return -EFAULT; 1073 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1074 pp->mode = smu_file_events; 1075 return 0; 1076 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1077 struct smu_sdbp_header *part; 1078 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1079 if (part == NULL) 1080 return -EINVAL; 1081 else if (IS_ERR(part)) 1082 return PTR_ERR(part); 1083 return 0; 1084 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1085 return -EINVAL; 1086 else if (pp->mode != smu_file_commands) 1087 return -EBADFD; 1088 else if (hdr.data_len > SMU_MAX_DATA) 1089 return -EINVAL; 1090 1091 spin_lock_irqsave(&pp->lock, flags); 1092 if (pp->busy) { 1093 spin_unlock_irqrestore(&pp->lock, flags); 1094 return -EBUSY; 1095 } 1096 pp->busy = 1; 1097 pp->cmd.status = 1; 1098 spin_unlock_irqrestore(&pp->lock, flags); 1099 1100 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1101 pp->busy = 0; 1102 return -EFAULT; 1103 } 1104 1105 pp->cmd.cmd = hdr.cmd; 1106 pp->cmd.data_len = hdr.data_len; 1107 pp->cmd.reply_len = SMU_MAX_DATA; 1108 pp->cmd.data_buf = pp->buffer; 1109 pp->cmd.reply_buf = pp->buffer; 1110 pp->cmd.done = smu_user_cmd_done; 1111 pp->cmd.misc = pp; 1112 rc = smu_queue_cmd(&pp->cmd); 1113 if (rc < 0) 1114 return rc; 1115 return count; 1116 } 1117 1118 1119 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1120 char __user *buf, size_t count) 1121 { 1122 DECLARE_WAITQUEUE(wait, current); 1123 struct smu_user_reply_hdr hdr; 1124 unsigned long flags; 1125 int size, rc = 0; 1126 1127 if (!pp->busy) 1128 return 0; 1129 if (count < sizeof(struct smu_user_reply_hdr)) 1130 return -EOVERFLOW; 1131 spin_lock_irqsave(&pp->lock, flags); 1132 if (pp->cmd.status == 1) { 1133 if (file->f_flags & O_NONBLOCK) 1134 return -EAGAIN; 1135 add_wait_queue(&pp->wait, &wait); 1136 for (;;) { 1137 set_current_state(TASK_INTERRUPTIBLE); 1138 rc = 0; 1139 if (pp->cmd.status != 1) 1140 break; 1141 rc = -ERESTARTSYS; 1142 if (signal_pending(current)) 1143 break; 1144 spin_unlock_irqrestore(&pp->lock, flags); 1145 schedule(); 1146 spin_lock_irqsave(&pp->lock, flags); 1147 } 1148 set_current_state(TASK_RUNNING); 1149 remove_wait_queue(&pp->wait, &wait); 1150 } 1151 spin_unlock_irqrestore(&pp->lock, flags); 1152 if (rc) 1153 return rc; 1154 if (pp->cmd.status != 0) 1155 pp->cmd.reply_len = 0; 1156 size = sizeof(hdr) + pp->cmd.reply_len; 1157 if (count < size) 1158 size = count; 1159 rc = size; 1160 hdr.status = pp->cmd.status; 1161 hdr.reply_len = pp->cmd.reply_len; 1162 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1163 return -EFAULT; 1164 size -= sizeof(hdr); 1165 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1166 return -EFAULT; 1167 pp->busy = 0; 1168 1169 return rc; 1170 } 1171 1172 1173 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1174 char __user *buf, size_t count) 1175 { 1176 /* Not implemented */ 1177 msleep_interruptible(1000); 1178 return 0; 1179 } 1180 1181 1182 static ssize_t smu_read(struct file *file, char __user *buf, 1183 size_t count, loff_t *ppos) 1184 { 1185 struct smu_private *pp = file->private_data; 1186 1187 if (pp->mode == smu_file_commands) 1188 return smu_read_command(file, pp, buf, count); 1189 if (pp->mode == smu_file_events) 1190 return smu_read_events(file, pp, buf, count); 1191 1192 return -EBADFD; 1193 } 1194 1195 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1196 { 1197 struct smu_private *pp = file->private_data; 1198 unsigned int mask = 0; 1199 unsigned long flags; 1200 1201 if (pp == 0) 1202 return 0; 1203 1204 if (pp->mode == smu_file_commands) { 1205 poll_wait(file, &pp->wait, wait); 1206 1207 spin_lock_irqsave(&pp->lock, flags); 1208 if (pp->busy && pp->cmd.status != 1) 1209 mask |= POLLIN; 1210 spin_unlock_irqrestore(&pp->lock, flags); 1211 } if (pp->mode == smu_file_events) { 1212 /* Not yet implemented */ 1213 } 1214 return mask; 1215 } 1216 1217 static int smu_release(struct inode *inode, struct file *file) 1218 { 1219 struct smu_private *pp = file->private_data; 1220 unsigned long flags; 1221 unsigned int busy; 1222 1223 if (pp == 0) 1224 return 0; 1225 1226 file->private_data = NULL; 1227 1228 /* Mark file as closing to avoid races with new request */ 1229 spin_lock_irqsave(&pp->lock, flags); 1230 pp->mode = smu_file_closing; 1231 busy = pp->busy; 1232 1233 /* Wait for any pending request to complete */ 1234 if (busy && pp->cmd.status == 1) { 1235 DECLARE_WAITQUEUE(wait, current); 1236 1237 add_wait_queue(&pp->wait, &wait); 1238 for (;;) { 1239 set_current_state(TASK_UNINTERRUPTIBLE); 1240 if (pp->cmd.status != 1) 1241 break; 1242 spin_lock_irqsave(&pp->lock, flags); 1243 schedule(); 1244 spin_unlock_irqrestore(&pp->lock, flags); 1245 } 1246 set_current_state(TASK_RUNNING); 1247 remove_wait_queue(&pp->wait, &wait); 1248 } 1249 spin_unlock_irqrestore(&pp->lock, flags); 1250 1251 spin_lock_irqsave(&smu_clist_lock, flags); 1252 list_del(&pp->list); 1253 spin_unlock_irqrestore(&smu_clist_lock, flags); 1254 kfree(pp); 1255 1256 return 0; 1257 } 1258 1259 1260 static struct file_operations smu_device_fops = { 1261 .llseek = no_llseek, 1262 .read = smu_read, 1263 .write = smu_write, 1264 .poll = smu_fpoll, 1265 .open = smu_open, 1266 .release = smu_release, 1267 }; 1268 1269 static struct miscdevice pmu_device = { 1270 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1271 }; 1272 1273 static int smu_device_init(void) 1274 { 1275 if (!smu) 1276 return -ENODEV; 1277 if (misc_register(&pmu_device) < 0) 1278 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1279 return 0; 1280 } 1281 device_initcall(smu_device_init); 1282