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 { printk(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 static void smu_i2c_retry(unsigned long data); 98 99 /* 100 * SMU driver low level stuff 101 */ 102 103 static void smu_start_cmd(void) 104 { 105 unsigned long faddr, fend; 106 struct smu_cmd *cmd; 107 108 if (list_empty(&smu->cmd_list)) 109 return; 110 111 /* Fetch first command in queue */ 112 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 113 smu->cmd_cur = cmd; 114 list_del(&cmd->link); 115 116 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 117 cmd->data_len); 118 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 119 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 120 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 121 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 122 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 123 124 /* Fill the SMU command buffer */ 125 smu->cmd_buf->cmd = cmd->cmd; 126 smu->cmd_buf->length = cmd->data_len; 127 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 128 129 /* Flush command and data to RAM */ 130 faddr = (unsigned long)smu->cmd_buf; 131 fend = faddr + smu->cmd_buf->length + 2; 132 flush_inval_dcache_range(faddr, fend); 133 134 /* This isn't exactly a DMA mapping here, I suspect 135 * the SMU is actually communicating with us via i2c to the 136 * northbridge or the CPU to access RAM. 137 */ 138 writel(smu->cmd_buf_abs, smu->db_buf); 139 140 /* Ring the SMU doorbell */ 141 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 142 } 143 144 145 static irqreturn_t smu_db_intr(int irq, void *arg, struct pt_regs *regs) 146 { 147 unsigned long flags; 148 struct smu_cmd *cmd; 149 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 150 void *misc = NULL; 151 u8 gpio; 152 int rc = 0; 153 154 /* SMU completed the command, well, we hope, let's make sure 155 * of it 156 */ 157 spin_lock_irqsave(&smu->lock, flags); 158 159 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 160 if ((gpio & 7) != 7) { 161 spin_unlock_irqrestore(&smu->lock, flags); 162 return IRQ_HANDLED; 163 } 164 165 cmd = smu->cmd_cur; 166 smu->cmd_cur = NULL; 167 if (cmd == NULL) 168 goto bail; 169 170 if (rc == 0) { 171 unsigned long faddr; 172 int reply_len; 173 u8 ack; 174 175 /* CPU might have brought back the cache line, so we need 176 * to flush again before peeking at the SMU response. We 177 * flush the entire buffer for now as we haven't read the 178 * reply lenght (it's only 2 cache lines anyway) 179 */ 180 faddr = (unsigned long)smu->cmd_buf; 181 flush_inval_dcache_range(faddr, faddr + 256); 182 183 /* Now check ack */ 184 ack = (~cmd->cmd) & 0xff; 185 if (ack != smu->cmd_buf->cmd) { 186 DPRINTK("SMU: incorrect ack, want %x got %x\n", 187 ack, smu->cmd_buf->cmd); 188 rc = -EIO; 189 } 190 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 191 DPRINTK("SMU: reply len: %d\n", reply_len); 192 if (reply_len > cmd->reply_len) { 193 printk(KERN_WARNING "SMU: reply buffer too small," 194 "got %d bytes for a %d bytes buffer\n", 195 reply_len, cmd->reply_len); 196 reply_len = cmd->reply_len; 197 } 198 cmd->reply_len = reply_len; 199 if (cmd->reply_buf && reply_len) 200 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 201 } 202 203 /* Now complete the command. Write status last in order as we lost 204 * ownership of the command structure as soon as it's no longer -1 205 */ 206 done = cmd->done; 207 misc = cmd->misc; 208 mb(); 209 cmd->status = rc; 210 bail: 211 /* Start next command if any */ 212 smu_start_cmd(); 213 spin_unlock_irqrestore(&smu->lock, flags); 214 215 /* Call command completion handler if any */ 216 if (done) 217 done(cmd, misc); 218 219 /* It's an edge interrupt, nothing to do */ 220 return IRQ_HANDLED; 221 } 222 223 224 static irqreturn_t smu_msg_intr(int irq, void *arg, struct pt_regs *regs) 225 { 226 /* I don't quite know what to do with this one, we seem to never 227 * receive it, so I suspect we have to arm it someway in the SMU 228 * to start getting events that way. 229 */ 230 231 printk(KERN_INFO "SMU: message interrupt !\n"); 232 233 /* It's an edge interrupt, nothing to do */ 234 return IRQ_HANDLED; 235 } 236 237 238 /* 239 * Queued command management. 240 * 241 */ 242 243 int smu_queue_cmd(struct smu_cmd *cmd) 244 { 245 unsigned long flags; 246 247 if (smu == NULL) 248 return -ENODEV; 249 if (cmd->data_len > SMU_MAX_DATA || 250 cmd->reply_len > SMU_MAX_DATA) 251 return -EINVAL; 252 253 cmd->status = 1; 254 spin_lock_irqsave(&smu->lock, flags); 255 list_add_tail(&cmd->link, &smu->cmd_list); 256 if (smu->cmd_cur == NULL) 257 smu_start_cmd(); 258 spin_unlock_irqrestore(&smu->lock, flags); 259 260 return 0; 261 } 262 EXPORT_SYMBOL(smu_queue_cmd); 263 264 265 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 266 unsigned int data_len, 267 void (*done)(struct smu_cmd *cmd, void *misc), 268 void *misc, ...) 269 { 270 struct smu_cmd *cmd = &scmd->cmd; 271 va_list list; 272 int i; 273 274 if (data_len > sizeof(scmd->buffer)) 275 return -EINVAL; 276 277 memset(scmd, 0, sizeof(*scmd)); 278 cmd->cmd = command; 279 cmd->data_len = data_len; 280 cmd->data_buf = scmd->buffer; 281 cmd->reply_len = sizeof(scmd->buffer); 282 cmd->reply_buf = scmd->buffer; 283 cmd->done = done; 284 cmd->misc = misc; 285 286 va_start(list, misc); 287 for (i = 0; i < data_len; ++i) 288 scmd->buffer[i] = (u8)va_arg(list, int); 289 va_end(list); 290 291 return smu_queue_cmd(cmd); 292 } 293 EXPORT_SYMBOL(smu_queue_simple); 294 295 296 void smu_poll(void) 297 { 298 u8 gpio; 299 300 if (smu == NULL) 301 return; 302 303 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 304 if ((gpio & 7) == 7) 305 smu_db_intr(smu->db_irq, smu, NULL); 306 } 307 EXPORT_SYMBOL(smu_poll); 308 309 310 void smu_done_complete(struct smu_cmd *cmd, void *misc) 311 { 312 struct completion *comp = misc; 313 314 complete(comp); 315 } 316 EXPORT_SYMBOL(smu_done_complete); 317 318 319 void smu_spinwait_cmd(struct smu_cmd *cmd) 320 { 321 while(cmd->status == 1) 322 smu_poll(); 323 } 324 EXPORT_SYMBOL(smu_spinwait_cmd); 325 326 327 /* RTC low level commands */ 328 static inline int bcd2hex (int n) 329 { 330 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 331 } 332 333 334 static inline int hex2bcd (int n) 335 { 336 return ((n / 10) << 4) + (n % 10); 337 } 338 339 340 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 341 struct rtc_time *time) 342 { 343 cmd_buf->cmd = 0x8e; 344 cmd_buf->length = 8; 345 cmd_buf->data[0] = 0x80; 346 cmd_buf->data[1] = hex2bcd(time->tm_sec); 347 cmd_buf->data[2] = hex2bcd(time->tm_min); 348 cmd_buf->data[3] = hex2bcd(time->tm_hour); 349 cmd_buf->data[4] = time->tm_wday; 350 cmd_buf->data[5] = hex2bcd(time->tm_mday); 351 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 352 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 353 } 354 355 356 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 357 { 358 struct smu_simple_cmd cmd; 359 int rc; 360 361 if (smu == NULL) 362 return -ENODEV; 363 364 memset(time, 0, sizeof(struct rtc_time)); 365 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 366 SMU_CMD_RTC_GET_DATETIME); 367 if (rc) 368 return rc; 369 smu_spinwait_simple(&cmd); 370 371 time->tm_sec = bcd2hex(cmd.buffer[0]); 372 time->tm_min = bcd2hex(cmd.buffer[1]); 373 time->tm_hour = bcd2hex(cmd.buffer[2]); 374 time->tm_wday = bcd2hex(cmd.buffer[3]); 375 time->tm_mday = bcd2hex(cmd.buffer[4]); 376 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 377 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 378 379 return 0; 380 } 381 382 383 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 384 { 385 struct smu_simple_cmd cmd; 386 int rc; 387 388 if (smu == NULL) 389 return -ENODEV; 390 391 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 392 SMU_CMD_RTC_SET_DATETIME, 393 hex2bcd(time->tm_sec), 394 hex2bcd(time->tm_min), 395 hex2bcd(time->tm_hour), 396 time->tm_wday, 397 hex2bcd(time->tm_mday), 398 hex2bcd(time->tm_mon) + 1, 399 hex2bcd(time->tm_year - 100)); 400 if (rc) 401 return rc; 402 smu_spinwait_simple(&cmd); 403 404 return 0; 405 } 406 407 408 void smu_shutdown(void) 409 { 410 struct smu_simple_cmd cmd; 411 412 if (smu == NULL) 413 return; 414 415 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 416 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 417 return; 418 smu_spinwait_simple(&cmd); 419 for (;;) 420 ; 421 } 422 423 424 void smu_restart(void) 425 { 426 struct smu_simple_cmd cmd; 427 428 if (smu == NULL) 429 return; 430 431 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 432 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 433 return; 434 smu_spinwait_simple(&cmd); 435 for (;;) 436 ; 437 } 438 439 440 int smu_present(void) 441 { 442 return smu != NULL; 443 } 444 EXPORT_SYMBOL(smu_present); 445 446 447 int __init smu_init (void) 448 { 449 struct device_node *np; 450 u32 *data; 451 452 np = of_find_node_by_type(NULL, "smu"); 453 if (np == NULL) 454 return -ENODEV; 455 456 printk(KERN_INFO "SMU driver %s %s\n", VERSION, AUTHOR); 457 458 if (smu_cmdbuf_abs == 0) { 459 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 460 return -EINVAL; 461 } 462 463 smu = alloc_bootmem(sizeof(struct smu_device)); 464 if (smu == NULL) 465 return -ENOMEM; 466 memset(smu, 0, sizeof(*smu)); 467 468 spin_lock_init(&smu->lock); 469 INIT_LIST_HEAD(&smu->cmd_list); 470 INIT_LIST_HEAD(&smu->cmd_i2c_list); 471 smu->of_node = np; 472 smu->db_irq = NO_IRQ; 473 smu->msg_irq = NO_IRQ; 474 475 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 476 * 32 bits value safely 477 */ 478 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 479 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); 480 481 np = of_find_node_by_name(NULL, "smu-doorbell"); 482 if (np == NULL) { 483 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 484 goto fail; 485 } 486 data = (u32 *)get_property(np, "reg", NULL); 487 if (data == NULL) { 488 of_node_put(np); 489 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 490 goto fail; 491 } 492 493 /* Current setup has one doorbell GPIO that does both doorbell 494 * and ack. GPIOs are at 0x50, best would be to find that out 495 * in the device-tree though. 496 */ 497 smu->doorbell = *data; 498 if (smu->doorbell < 0x50) 499 smu->doorbell += 0x50; 500 if (np->n_intrs > 0) 501 smu->db_irq = np->intrs[0].line; 502 503 of_node_put(np); 504 505 /* Now look for the smu-interrupt GPIO */ 506 do { 507 np = of_find_node_by_name(NULL, "smu-interrupt"); 508 if (np == NULL) 509 break; 510 data = (u32 *)get_property(np, "reg", NULL); 511 if (data == NULL) { 512 of_node_put(np); 513 break; 514 } 515 smu->msg = *data; 516 if (smu->msg < 0x50) 517 smu->msg += 0x50; 518 if (np->n_intrs > 0) 519 smu->msg_irq = np->intrs[0].line; 520 of_node_put(np); 521 } while(0); 522 523 /* Doorbell buffer is currently hard-coded, I didn't find a proper 524 * device-tree entry giving the address. Best would probably to use 525 * an offset for K2 base though, but let's do it that way for now. 526 */ 527 smu->db_buf = ioremap(0x8000860c, 0x1000); 528 if (smu->db_buf == NULL) { 529 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 530 goto fail; 531 } 532 533 sys_ctrler = SYS_CTRLER_SMU; 534 return 0; 535 536 fail: 537 smu = NULL; 538 return -ENXIO; 539 540 } 541 542 543 static int smu_late_init(void) 544 { 545 if (!smu) 546 return 0; 547 548 init_timer(&smu->i2c_timer); 549 smu->i2c_timer.function = smu_i2c_retry; 550 smu->i2c_timer.data = (unsigned long)smu; 551 552 /* 553 * Try to request the interrupts 554 */ 555 556 if (smu->db_irq != NO_IRQ) { 557 if (request_irq(smu->db_irq, smu_db_intr, 558 SA_SHIRQ, "SMU doorbell", smu) < 0) { 559 printk(KERN_WARNING "SMU: can't " 560 "request interrupt %d\n", 561 smu->db_irq); 562 smu->db_irq = NO_IRQ; 563 } 564 } 565 566 if (smu->msg_irq != NO_IRQ) { 567 if (request_irq(smu->msg_irq, smu_msg_intr, 568 SA_SHIRQ, "SMU message", smu) < 0) { 569 printk(KERN_WARNING "SMU: can't " 570 "request interrupt %d\n", 571 smu->msg_irq); 572 smu->msg_irq = NO_IRQ; 573 } 574 } 575 576 return 0; 577 } 578 /* This has to be before arch_initcall as the low i2c stuff relies on the 579 * above having been done before we reach arch_initcalls 580 */ 581 core_initcall(smu_late_init); 582 583 /* 584 * sysfs visibility 585 */ 586 587 static void smu_expose_childs(void *unused) 588 { 589 struct device_node *np; 590 591 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 592 if (device_is_compatible(np, "smu-sensors")) 593 of_platform_device_create(np, "smu-sensors", 594 &smu->of_dev->dev); 595 } 596 597 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs, NULL); 598 599 static int smu_platform_probe(struct of_device* dev, 600 const struct of_device_id *match) 601 { 602 if (!smu) 603 return -ENODEV; 604 smu->of_dev = dev; 605 606 /* 607 * Ok, we are matched, now expose all i2c busses. We have to defer 608 * that unfortunately or it would deadlock inside the device model 609 */ 610 schedule_work(&smu_expose_childs_work); 611 612 return 0; 613 } 614 615 static struct of_device_id smu_platform_match[] = 616 { 617 { 618 .type = "smu", 619 }, 620 {}, 621 }; 622 623 static struct of_platform_driver smu_of_platform_driver = 624 { 625 .name = "smu", 626 .match_table = smu_platform_match, 627 .probe = smu_platform_probe, 628 }; 629 630 static int __init smu_init_sysfs(void) 631 { 632 int rc; 633 634 /* 635 * Due to sysfs bogosity, a sysdev is not a real device, so 636 * we should in fact create both if we want sysdev semantics 637 * for power management. 638 * For now, we don't power manage machines with an SMU chip, 639 * I'm a bit too far from figuring out how that works with those 640 * new chipsets, but that will come back and bite us 641 */ 642 rc = of_register_driver(&smu_of_platform_driver); 643 return 0; 644 } 645 646 device_initcall(smu_init_sysfs); 647 648 struct of_device *smu_get_ofdev(void) 649 { 650 if (!smu) 651 return NULL; 652 return smu->of_dev; 653 } 654 655 EXPORT_SYMBOL_GPL(smu_get_ofdev); 656 657 /* 658 * i2c interface 659 */ 660 661 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 662 { 663 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 664 void *misc = cmd->misc; 665 unsigned long flags; 666 667 /* Check for read case */ 668 if (!fail && cmd->read) { 669 if (cmd->pdata[0] < 1) 670 fail = 1; 671 else 672 memcpy(cmd->info.data, &cmd->pdata[1], 673 cmd->info.datalen); 674 } 675 676 DPRINTK("SMU: completing, success: %d\n", !fail); 677 678 /* Update status and mark no pending i2c command with lock 679 * held so nobody comes in while we dequeue an eventual 680 * pending next i2c command 681 */ 682 spin_lock_irqsave(&smu->lock, flags); 683 smu->cmd_i2c_cur = NULL; 684 wmb(); 685 cmd->status = fail ? -EIO : 0; 686 687 /* Is there another i2c command waiting ? */ 688 if (!list_empty(&smu->cmd_i2c_list)) { 689 struct smu_i2c_cmd *newcmd; 690 691 /* Fetch it, new current, remove from list */ 692 newcmd = list_entry(smu->cmd_i2c_list.next, 693 struct smu_i2c_cmd, link); 694 smu->cmd_i2c_cur = newcmd; 695 list_del(&cmd->link); 696 697 /* Queue with low level smu */ 698 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 699 if (smu->cmd_cur == NULL) 700 smu_start_cmd(); 701 } 702 spin_unlock_irqrestore(&smu->lock, flags); 703 704 /* Call command completion handler if any */ 705 if (done) 706 done(cmd, misc); 707 708 } 709 710 711 static void smu_i2c_retry(unsigned long data) 712 { 713 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 714 715 DPRINTK("SMU: i2c failure, requeuing...\n"); 716 717 /* requeue command simply by resetting reply_len */ 718 cmd->pdata[0] = 0xff; 719 cmd->scmd.reply_len = sizeof(cmd->pdata); 720 smu_queue_cmd(&cmd->scmd); 721 } 722 723 724 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 725 { 726 struct smu_i2c_cmd *cmd = misc; 727 int fail = 0; 728 729 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 730 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 731 732 /* Check for possible status */ 733 if (scmd->status < 0) 734 fail = 1; 735 else if (cmd->read) { 736 if (cmd->stage == 0) 737 fail = cmd->pdata[0] != 0; 738 else 739 fail = cmd->pdata[0] >= 0x80; 740 } else { 741 fail = cmd->pdata[0] != 0; 742 } 743 744 /* Handle failures by requeuing command, after 5ms interval 745 */ 746 if (fail && --cmd->retries > 0) { 747 DPRINTK("SMU: i2c failure, starting timer...\n"); 748 BUG_ON(cmd != smu->cmd_i2c_cur); 749 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 750 return; 751 } 752 753 /* If failure or stage 1, command is complete */ 754 if (fail || cmd->stage != 0) { 755 smu_i2c_complete_command(cmd, fail); 756 return; 757 } 758 759 DPRINTK("SMU: going to stage 1\n"); 760 761 /* Ok, initial command complete, now poll status */ 762 scmd->reply_buf = cmd->pdata; 763 scmd->reply_len = sizeof(cmd->pdata); 764 scmd->data_buf = cmd->pdata; 765 scmd->data_len = 1; 766 cmd->pdata[0] = 0; 767 cmd->stage = 1; 768 cmd->retries = 20; 769 smu_queue_cmd(scmd); 770 } 771 772 773 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 774 { 775 unsigned long flags; 776 777 if (smu == NULL) 778 return -ENODEV; 779 780 /* Fill most fields of scmd */ 781 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 782 cmd->scmd.done = smu_i2c_low_completion; 783 cmd->scmd.misc = cmd; 784 cmd->scmd.reply_buf = cmd->pdata; 785 cmd->scmd.reply_len = sizeof(cmd->pdata); 786 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 787 cmd->scmd.status = 1; 788 cmd->stage = 0; 789 cmd->pdata[0] = 0xff; 790 cmd->retries = 20; 791 cmd->status = 1; 792 793 /* Check transfer type, sanitize some "info" fields 794 * based on transfer type and do more checking 795 */ 796 cmd->info.caddr = cmd->info.devaddr; 797 cmd->read = cmd->info.devaddr & 0x01; 798 switch(cmd->info.type) { 799 case SMU_I2C_TRANSFER_SIMPLE: 800 memset(&cmd->info.sublen, 0, 4); 801 break; 802 case SMU_I2C_TRANSFER_COMBINED: 803 cmd->info.devaddr &= 0xfe; 804 case SMU_I2C_TRANSFER_STDSUB: 805 if (cmd->info.sublen > 3) 806 return -EINVAL; 807 break; 808 default: 809 return -EINVAL; 810 } 811 812 /* Finish setting up command based on transfer direction 813 */ 814 if (cmd->read) { 815 if (cmd->info.datalen > SMU_I2C_READ_MAX) 816 return -EINVAL; 817 memset(cmd->info.data, 0xff, cmd->info.datalen); 818 cmd->scmd.data_len = 9; 819 } else { 820 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 821 return -EINVAL; 822 cmd->scmd.data_len = 9 + cmd->info.datalen; 823 } 824 825 DPRINTK("SMU: i2c enqueuing command\n"); 826 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 827 cmd->read ? "read" : "write", cmd->info.datalen, 828 cmd->info.bus, cmd->info.caddr, 829 cmd->info.subaddr[0], cmd->info.type); 830 831 832 /* Enqueue command in i2c list, and if empty, enqueue also in 833 * main command list 834 */ 835 spin_lock_irqsave(&smu->lock, flags); 836 if (smu->cmd_i2c_cur == NULL) { 837 smu->cmd_i2c_cur = cmd; 838 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 839 if (smu->cmd_cur == NULL) 840 smu_start_cmd(); 841 } else 842 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 843 spin_unlock_irqrestore(&smu->lock, flags); 844 845 return 0; 846 } 847 848 /* 849 * Handling of "partitions" 850 */ 851 852 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 853 { 854 DECLARE_COMPLETION(comp); 855 unsigned int chunk; 856 struct smu_cmd cmd; 857 int rc; 858 u8 params[8]; 859 860 /* We currently use a chunk size of 0xe. We could check the 861 * SMU firmware version and use bigger sizes though 862 */ 863 chunk = 0xe; 864 865 while (len) { 866 unsigned int clen = min(len, chunk); 867 868 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 869 cmd.data_len = 7; 870 cmd.data_buf = params; 871 cmd.reply_len = chunk; 872 cmd.reply_buf = dest; 873 cmd.done = smu_done_complete; 874 cmd.misc = ∁ 875 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 876 params[1] = 0x4; 877 *((u32 *)¶ms[2]) = addr; 878 params[6] = clen; 879 880 rc = smu_queue_cmd(&cmd); 881 if (rc) 882 return rc; 883 wait_for_completion(&comp); 884 if (cmd.status != 0) 885 return rc; 886 if (cmd.reply_len != clen) { 887 printk(KERN_DEBUG "SMU: short read in " 888 "smu_read_datablock, got: %d, want: %d\n", 889 cmd.reply_len, clen); 890 return -EIO; 891 } 892 len -= clen; 893 addr += clen; 894 dest += clen; 895 } 896 return 0; 897 } 898 899 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 900 { 901 DECLARE_COMPLETION(comp); 902 struct smu_simple_cmd cmd; 903 unsigned int addr, len, tlen; 904 struct smu_sdbp_header *hdr; 905 struct property *prop; 906 907 /* First query the partition info */ 908 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 909 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 910 smu_done_complete, &comp, 911 SMU_CMD_PARTITION_LATEST, id); 912 wait_for_completion(&comp); 913 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 914 cmd.cmd.status, cmd.cmd.reply_len); 915 916 /* Partition doesn't exist (or other error) */ 917 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 918 return NULL; 919 920 /* Fetch address and length from reply */ 921 addr = *((u16 *)cmd.buffer); 922 len = cmd.buffer[3] << 2; 923 /* Calucluate total length to allocate, including the 17 bytes 924 * for "sdb-partition-XX" that we append at the end of the buffer 925 */ 926 tlen = sizeof(struct property) + len + 18; 927 928 prop = kcalloc(tlen, 1, GFP_KERNEL); 929 if (prop == NULL) 930 return NULL; 931 hdr = (struct smu_sdbp_header *)(prop + 1); 932 prop->name = ((char *)prop) + tlen - 18; 933 sprintf(prop->name, "sdb-partition-%02x", id); 934 prop->length = len; 935 prop->value = (unsigned char *)hdr; 936 prop->next = NULL; 937 938 /* Read the datablock */ 939 if (smu_read_datablock((u8 *)hdr, addr, len)) { 940 printk(KERN_DEBUG "SMU: datablock read failed while reading " 941 "partition %02x !\n", id); 942 goto failure; 943 } 944 945 /* Got it, check a few things and create the property */ 946 if (hdr->id != id) { 947 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 948 "%02x !\n", id, hdr->id); 949 goto failure; 950 } 951 if (prom_add_property(smu->of_node, prop)) { 952 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 953 "property !\n", id); 954 goto failure; 955 } 956 957 return hdr; 958 failure: 959 kfree(prop); 960 return NULL; 961 } 962 963 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 964 * when interruptible is 1 965 */ 966 struct smu_sdbp_header *__smu_get_sdb_partition(int id, unsigned int *size, 967 int interruptible) 968 { 969 char pname[32]; 970 struct smu_sdbp_header *part; 971 972 if (!smu) 973 return NULL; 974 975 sprintf(pname, "sdb-partition-%02x", id); 976 977 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 978 979 if (interruptible) { 980 int rc; 981 rc = down_interruptible(&smu_part_access); 982 if (rc) 983 return ERR_PTR(rc); 984 } else 985 down(&smu_part_access); 986 987 part = (struct smu_sdbp_header *)get_property(smu->of_node, 988 pname, size); 989 if (part == NULL) { 990 DPRINTK("trying to extract from SMU ...\n"); 991 part = smu_create_sdb_partition(id); 992 if (part != NULL && size) 993 *size = part->len << 2; 994 } 995 up(&smu_part_access); 996 return part; 997 } 998 999 struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1000 { 1001 return __smu_get_sdb_partition(id, size, 0); 1002 } 1003 EXPORT_SYMBOL(smu_get_sdb_partition); 1004 1005 1006 /* 1007 * Userland driver interface 1008 */ 1009 1010 1011 static LIST_HEAD(smu_clist); 1012 static DEFINE_SPINLOCK(smu_clist_lock); 1013 1014 enum smu_file_mode { 1015 smu_file_commands, 1016 smu_file_events, 1017 smu_file_closing 1018 }; 1019 1020 struct smu_private 1021 { 1022 struct list_head list; 1023 enum smu_file_mode mode; 1024 int busy; 1025 struct smu_cmd cmd; 1026 spinlock_t lock; 1027 wait_queue_head_t wait; 1028 u8 buffer[SMU_MAX_DATA]; 1029 }; 1030 1031 1032 static int smu_open(struct inode *inode, struct file *file) 1033 { 1034 struct smu_private *pp; 1035 unsigned long flags; 1036 1037 pp = kmalloc(sizeof(struct smu_private), GFP_KERNEL); 1038 if (pp == 0) 1039 return -ENOMEM; 1040 memset(pp, 0, sizeof(struct smu_private)); 1041 spin_lock_init(&pp->lock); 1042 pp->mode = smu_file_commands; 1043 init_waitqueue_head(&pp->wait); 1044 1045 spin_lock_irqsave(&smu_clist_lock, flags); 1046 list_add(&pp->list, &smu_clist); 1047 spin_unlock_irqrestore(&smu_clist_lock, flags); 1048 file->private_data = pp; 1049 1050 return 0; 1051 } 1052 1053 1054 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1055 { 1056 struct smu_private *pp = misc; 1057 1058 wake_up_all(&pp->wait); 1059 } 1060 1061 1062 static ssize_t smu_write(struct file *file, const char __user *buf, 1063 size_t count, loff_t *ppos) 1064 { 1065 struct smu_private *pp = file->private_data; 1066 unsigned long flags; 1067 struct smu_user_cmd_hdr hdr; 1068 int rc = 0; 1069 1070 if (pp->busy) 1071 return -EBUSY; 1072 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1073 return -EFAULT; 1074 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1075 pp->mode = smu_file_events; 1076 return 0; 1077 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1078 struct smu_sdbp_header *part; 1079 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1080 if (part == NULL) 1081 return -EINVAL; 1082 else if (IS_ERR(part)) 1083 return PTR_ERR(part); 1084 return 0; 1085 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1086 return -EINVAL; 1087 else if (pp->mode != smu_file_commands) 1088 return -EBADFD; 1089 else if (hdr.data_len > SMU_MAX_DATA) 1090 return -EINVAL; 1091 1092 spin_lock_irqsave(&pp->lock, flags); 1093 if (pp->busy) { 1094 spin_unlock_irqrestore(&pp->lock, flags); 1095 return -EBUSY; 1096 } 1097 pp->busy = 1; 1098 pp->cmd.status = 1; 1099 spin_unlock_irqrestore(&pp->lock, flags); 1100 1101 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1102 pp->busy = 0; 1103 return -EFAULT; 1104 } 1105 1106 pp->cmd.cmd = hdr.cmd; 1107 pp->cmd.data_len = hdr.data_len; 1108 pp->cmd.reply_len = SMU_MAX_DATA; 1109 pp->cmd.data_buf = pp->buffer; 1110 pp->cmd.reply_buf = pp->buffer; 1111 pp->cmd.done = smu_user_cmd_done; 1112 pp->cmd.misc = pp; 1113 rc = smu_queue_cmd(&pp->cmd); 1114 if (rc < 0) 1115 return rc; 1116 return count; 1117 } 1118 1119 1120 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1121 char __user *buf, size_t count) 1122 { 1123 DECLARE_WAITQUEUE(wait, current); 1124 struct smu_user_reply_hdr hdr; 1125 unsigned long flags; 1126 int size, rc = 0; 1127 1128 if (!pp->busy) 1129 return 0; 1130 if (count < sizeof(struct smu_user_reply_hdr)) 1131 return -EOVERFLOW; 1132 spin_lock_irqsave(&pp->lock, flags); 1133 if (pp->cmd.status == 1) { 1134 if (file->f_flags & O_NONBLOCK) 1135 return -EAGAIN; 1136 add_wait_queue(&pp->wait, &wait); 1137 for (;;) { 1138 set_current_state(TASK_INTERRUPTIBLE); 1139 rc = 0; 1140 if (pp->cmd.status != 1) 1141 break; 1142 rc = -ERESTARTSYS; 1143 if (signal_pending(current)) 1144 break; 1145 spin_unlock_irqrestore(&pp->lock, flags); 1146 schedule(); 1147 spin_lock_irqsave(&pp->lock, flags); 1148 } 1149 set_current_state(TASK_RUNNING); 1150 remove_wait_queue(&pp->wait, &wait); 1151 } 1152 spin_unlock_irqrestore(&pp->lock, flags); 1153 if (rc) 1154 return rc; 1155 if (pp->cmd.status != 0) 1156 pp->cmd.reply_len = 0; 1157 size = sizeof(hdr) + pp->cmd.reply_len; 1158 if (count < size) 1159 size = count; 1160 rc = size; 1161 hdr.status = pp->cmd.status; 1162 hdr.reply_len = pp->cmd.reply_len; 1163 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1164 return -EFAULT; 1165 size -= sizeof(hdr); 1166 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1167 return -EFAULT; 1168 pp->busy = 0; 1169 1170 return rc; 1171 } 1172 1173 1174 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1175 char __user *buf, size_t count) 1176 { 1177 /* Not implemented */ 1178 msleep_interruptible(1000); 1179 return 0; 1180 } 1181 1182 1183 static ssize_t smu_read(struct file *file, char __user *buf, 1184 size_t count, loff_t *ppos) 1185 { 1186 struct smu_private *pp = file->private_data; 1187 1188 if (pp->mode == smu_file_commands) 1189 return smu_read_command(file, pp, buf, count); 1190 if (pp->mode == smu_file_events) 1191 return smu_read_events(file, pp, buf, count); 1192 1193 return -EBADFD; 1194 } 1195 1196 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1197 { 1198 struct smu_private *pp = file->private_data; 1199 unsigned int mask = 0; 1200 unsigned long flags; 1201 1202 if (pp == 0) 1203 return 0; 1204 1205 if (pp->mode == smu_file_commands) { 1206 poll_wait(file, &pp->wait, wait); 1207 1208 spin_lock_irqsave(&pp->lock, flags); 1209 if (pp->busy && pp->cmd.status != 1) 1210 mask |= POLLIN; 1211 spin_unlock_irqrestore(&pp->lock, flags); 1212 } if (pp->mode == smu_file_events) { 1213 /* Not yet implemented */ 1214 } 1215 return mask; 1216 } 1217 1218 static int smu_release(struct inode *inode, struct file *file) 1219 { 1220 struct smu_private *pp = file->private_data; 1221 unsigned long flags; 1222 unsigned int busy; 1223 1224 if (pp == 0) 1225 return 0; 1226 1227 file->private_data = NULL; 1228 1229 /* Mark file as closing to avoid races with new request */ 1230 spin_lock_irqsave(&pp->lock, flags); 1231 pp->mode = smu_file_closing; 1232 busy = pp->busy; 1233 1234 /* Wait for any pending request to complete */ 1235 if (busy && pp->cmd.status == 1) { 1236 DECLARE_WAITQUEUE(wait, current); 1237 1238 add_wait_queue(&pp->wait, &wait); 1239 for (;;) { 1240 set_current_state(TASK_UNINTERRUPTIBLE); 1241 if (pp->cmd.status != 1) 1242 break; 1243 spin_lock_irqsave(&pp->lock, flags); 1244 schedule(); 1245 spin_unlock_irqrestore(&pp->lock, flags); 1246 } 1247 set_current_state(TASK_RUNNING); 1248 remove_wait_queue(&pp->wait, &wait); 1249 } 1250 spin_unlock_irqrestore(&pp->lock, flags); 1251 1252 spin_lock_irqsave(&smu_clist_lock, flags); 1253 list_del(&pp->list); 1254 spin_unlock_irqrestore(&smu_clist_lock, flags); 1255 kfree(pp); 1256 1257 return 0; 1258 } 1259 1260 1261 static struct file_operations smu_device_fops = { 1262 .llseek = no_llseek, 1263 .read = smu_read, 1264 .write = smu_write, 1265 .poll = smu_fpoll, 1266 .open = smu_open, 1267 .release = smu_release, 1268 }; 1269 1270 static struct miscdevice pmu_device = { 1271 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1272 }; 1273 1274 static int smu_device_init(void) 1275 { 1276 if (!smu) 1277 return -ENODEV; 1278 if (misc_register(&pmu_device) < 0) 1279 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1280 return 0; 1281 } 1282 device_initcall(smu_device_init); 1283