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/types.h> 23 #include <linux/kernel.h> 24 #include <linux/device.h> 25 #include <linux/dmapool.h> 26 #include <linux/bootmem.h> 27 #include <linux/vmalloc.h> 28 #include <linux/highmem.h> 29 #include <linux/jiffies.h> 30 #include <linux/interrupt.h> 31 #include <linux/rtc.h> 32 #include <linux/completion.h> 33 #include <linux/miscdevice.h> 34 #include <linux/delay.h> 35 #include <linux/sysdev.h> 36 #include <linux/poll.h> 37 #include <linux/mutex.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 #include <asm/of_platform.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 struct device_node *db_node; 80 unsigned int db_irq; 81 int msg; 82 struct device_node *msg_node; 83 unsigned int msg_irq; 84 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ 85 u32 cmd_buf_abs; /* command buffer absolute */ 86 struct list_head cmd_list; 87 struct smu_cmd *cmd_cur; /* pending command */ 88 struct list_head cmd_i2c_list; 89 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 90 struct timer_list i2c_timer; 91 }; 92 93 /* 94 * I don't think there will ever be more than one SMU, so 95 * for now, just hard code that 96 */ 97 static struct smu_device *smu; 98 static DEFINE_MUTEX(smu_part_access); 99 static int smu_irq_inited; 100 101 static void smu_i2c_retry(unsigned long data); 102 103 /* 104 * SMU driver low level stuff 105 */ 106 107 static void smu_start_cmd(void) 108 { 109 unsigned long faddr, fend; 110 struct smu_cmd *cmd; 111 112 if (list_empty(&smu->cmd_list)) 113 return; 114 115 /* Fetch first command in queue */ 116 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 117 smu->cmd_cur = cmd; 118 list_del(&cmd->link); 119 120 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 121 cmd->data_len); 122 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 123 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 124 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 125 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 126 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 127 128 /* Fill the SMU command buffer */ 129 smu->cmd_buf->cmd = cmd->cmd; 130 smu->cmd_buf->length = cmd->data_len; 131 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 132 133 /* Flush command and data to RAM */ 134 faddr = (unsigned long)smu->cmd_buf; 135 fend = faddr + smu->cmd_buf->length + 2; 136 flush_inval_dcache_range(faddr, fend); 137 138 /* This isn't exactly a DMA mapping here, I suspect 139 * the SMU is actually communicating with us via i2c to the 140 * northbridge or the CPU to access RAM. 141 */ 142 writel(smu->cmd_buf_abs, smu->db_buf); 143 144 /* Ring the SMU doorbell */ 145 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 146 } 147 148 149 static irqreturn_t smu_db_intr(int irq, void *arg) 150 { 151 unsigned long flags; 152 struct smu_cmd *cmd; 153 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 154 void *misc = NULL; 155 u8 gpio; 156 int rc = 0; 157 158 /* SMU completed the command, well, we hope, let's make sure 159 * of it 160 */ 161 spin_lock_irqsave(&smu->lock, flags); 162 163 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 164 if ((gpio & 7) != 7) { 165 spin_unlock_irqrestore(&smu->lock, flags); 166 return IRQ_HANDLED; 167 } 168 169 cmd = smu->cmd_cur; 170 smu->cmd_cur = NULL; 171 if (cmd == NULL) 172 goto bail; 173 174 if (rc == 0) { 175 unsigned long faddr; 176 int reply_len; 177 u8 ack; 178 179 /* CPU might have brought back the cache line, so we need 180 * to flush again before peeking at the SMU response. We 181 * flush the entire buffer for now as we haven't read the 182 * reply lenght (it's only 2 cache lines anyway) 183 */ 184 faddr = (unsigned long)smu->cmd_buf; 185 flush_inval_dcache_range(faddr, faddr + 256); 186 187 /* Now check ack */ 188 ack = (~cmd->cmd) & 0xff; 189 if (ack != smu->cmd_buf->cmd) { 190 DPRINTK("SMU: incorrect ack, want %x got %x\n", 191 ack, smu->cmd_buf->cmd); 192 rc = -EIO; 193 } 194 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 195 DPRINTK("SMU: reply len: %d\n", reply_len); 196 if (reply_len > cmd->reply_len) { 197 printk(KERN_WARNING "SMU: reply buffer too small," 198 "got %d bytes for a %d bytes buffer\n", 199 reply_len, cmd->reply_len); 200 reply_len = cmd->reply_len; 201 } 202 cmd->reply_len = reply_len; 203 if (cmd->reply_buf && reply_len) 204 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 205 } 206 207 /* Now complete the command. Write status last in order as we lost 208 * ownership of the command structure as soon as it's no longer -1 209 */ 210 done = cmd->done; 211 misc = cmd->misc; 212 mb(); 213 cmd->status = rc; 214 bail: 215 /* Start next command if any */ 216 smu_start_cmd(); 217 spin_unlock_irqrestore(&smu->lock, flags); 218 219 /* Call command completion handler if any */ 220 if (done) 221 done(cmd, misc); 222 223 /* It's an edge interrupt, nothing to do */ 224 return IRQ_HANDLED; 225 } 226 227 228 static irqreturn_t smu_msg_intr(int irq, void *arg) 229 { 230 /* I don't quite know what to do with this one, we seem to never 231 * receive it, so I suspect we have to arm it someway in the SMU 232 * to start getting events that way. 233 */ 234 235 printk(KERN_INFO "SMU: message interrupt !\n"); 236 237 /* It's an edge interrupt, nothing to do */ 238 return IRQ_HANDLED; 239 } 240 241 242 /* 243 * Queued command management. 244 * 245 */ 246 247 int smu_queue_cmd(struct smu_cmd *cmd) 248 { 249 unsigned long flags; 250 251 if (smu == NULL) 252 return -ENODEV; 253 if (cmd->data_len > SMU_MAX_DATA || 254 cmd->reply_len > SMU_MAX_DATA) 255 return -EINVAL; 256 257 cmd->status = 1; 258 spin_lock_irqsave(&smu->lock, flags); 259 list_add_tail(&cmd->link, &smu->cmd_list); 260 if (smu->cmd_cur == NULL) 261 smu_start_cmd(); 262 spin_unlock_irqrestore(&smu->lock, flags); 263 264 /* Workaround for early calls when irq isn't available */ 265 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 266 smu_spinwait_cmd(cmd); 267 268 return 0; 269 } 270 EXPORT_SYMBOL(smu_queue_cmd); 271 272 273 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 274 unsigned int data_len, 275 void (*done)(struct smu_cmd *cmd, void *misc), 276 void *misc, ...) 277 { 278 struct smu_cmd *cmd = &scmd->cmd; 279 va_list list; 280 int i; 281 282 if (data_len > sizeof(scmd->buffer)) 283 return -EINVAL; 284 285 memset(scmd, 0, sizeof(*scmd)); 286 cmd->cmd = command; 287 cmd->data_len = data_len; 288 cmd->data_buf = scmd->buffer; 289 cmd->reply_len = sizeof(scmd->buffer); 290 cmd->reply_buf = scmd->buffer; 291 cmd->done = done; 292 cmd->misc = misc; 293 294 va_start(list, misc); 295 for (i = 0; i < data_len; ++i) 296 scmd->buffer[i] = (u8)va_arg(list, int); 297 va_end(list); 298 299 return smu_queue_cmd(cmd); 300 } 301 EXPORT_SYMBOL(smu_queue_simple); 302 303 304 void smu_poll(void) 305 { 306 u8 gpio; 307 308 if (smu == NULL) 309 return; 310 311 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 312 if ((gpio & 7) == 7) 313 smu_db_intr(smu->db_irq, smu); 314 } 315 EXPORT_SYMBOL(smu_poll); 316 317 318 void smu_done_complete(struct smu_cmd *cmd, void *misc) 319 { 320 struct completion *comp = misc; 321 322 complete(comp); 323 } 324 EXPORT_SYMBOL(smu_done_complete); 325 326 327 void smu_spinwait_cmd(struct smu_cmd *cmd) 328 { 329 while(cmd->status == 1) 330 smu_poll(); 331 } 332 EXPORT_SYMBOL(smu_spinwait_cmd); 333 334 335 /* RTC low level commands */ 336 static inline int bcd2hex (int n) 337 { 338 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 339 } 340 341 342 static inline int hex2bcd (int n) 343 { 344 return ((n / 10) << 4) + (n % 10); 345 } 346 347 348 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 349 struct rtc_time *time) 350 { 351 cmd_buf->cmd = 0x8e; 352 cmd_buf->length = 8; 353 cmd_buf->data[0] = 0x80; 354 cmd_buf->data[1] = hex2bcd(time->tm_sec); 355 cmd_buf->data[2] = hex2bcd(time->tm_min); 356 cmd_buf->data[3] = hex2bcd(time->tm_hour); 357 cmd_buf->data[4] = time->tm_wday; 358 cmd_buf->data[5] = hex2bcd(time->tm_mday); 359 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 360 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 361 } 362 363 364 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 365 { 366 struct smu_simple_cmd cmd; 367 int rc; 368 369 if (smu == NULL) 370 return -ENODEV; 371 372 memset(time, 0, sizeof(struct rtc_time)); 373 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 374 SMU_CMD_RTC_GET_DATETIME); 375 if (rc) 376 return rc; 377 smu_spinwait_simple(&cmd); 378 379 time->tm_sec = bcd2hex(cmd.buffer[0]); 380 time->tm_min = bcd2hex(cmd.buffer[1]); 381 time->tm_hour = bcd2hex(cmd.buffer[2]); 382 time->tm_wday = bcd2hex(cmd.buffer[3]); 383 time->tm_mday = bcd2hex(cmd.buffer[4]); 384 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 385 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 386 387 return 0; 388 } 389 390 391 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 392 { 393 struct smu_simple_cmd cmd; 394 int rc; 395 396 if (smu == NULL) 397 return -ENODEV; 398 399 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 400 SMU_CMD_RTC_SET_DATETIME, 401 hex2bcd(time->tm_sec), 402 hex2bcd(time->tm_min), 403 hex2bcd(time->tm_hour), 404 time->tm_wday, 405 hex2bcd(time->tm_mday), 406 hex2bcd(time->tm_mon) + 1, 407 hex2bcd(time->tm_year - 100)); 408 if (rc) 409 return rc; 410 smu_spinwait_simple(&cmd); 411 412 return 0; 413 } 414 415 416 void smu_shutdown(void) 417 { 418 struct smu_simple_cmd cmd; 419 420 if (smu == NULL) 421 return; 422 423 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 424 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 425 return; 426 smu_spinwait_simple(&cmd); 427 for (;;) 428 ; 429 } 430 431 432 void smu_restart(void) 433 { 434 struct smu_simple_cmd cmd; 435 436 if (smu == NULL) 437 return; 438 439 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 440 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 441 return; 442 smu_spinwait_simple(&cmd); 443 for (;;) 444 ; 445 } 446 447 448 int smu_present(void) 449 { 450 return smu != NULL; 451 } 452 EXPORT_SYMBOL(smu_present); 453 454 455 int __init smu_init (void) 456 { 457 struct device_node *np; 458 const u32 *data; 459 460 np = of_find_node_by_type(NULL, "smu"); 461 if (np == NULL) 462 return -ENODEV; 463 464 printk(KERN_INFO "SMU driver %s %s\n", VERSION, AUTHOR); 465 466 if (smu_cmdbuf_abs == 0) { 467 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 468 return -EINVAL; 469 } 470 471 smu = alloc_bootmem(sizeof(struct smu_device)); 472 if (smu == NULL) 473 return -ENOMEM; 474 memset(smu, 0, sizeof(*smu)); 475 476 spin_lock_init(&smu->lock); 477 INIT_LIST_HEAD(&smu->cmd_list); 478 INIT_LIST_HEAD(&smu->cmd_i2c_list); 479 smu->of_node = np; 480 smu->db_irq = NO_IRQ; 481 smu->msg_irq = NO_IRQ; 482 483 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 484 * 32 bits value safely 485 */ 486 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 487 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); 488 489 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell"); 490 if (smu->db_node == NULL) { 491 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 492 goto fail; 493 } 494 data = of_get_property(smu->db_node, "reg", NULL); 495 if (data == NULL) { 496 of_node_put(smu->db_node); 497 smu->db_node = NULL; 498 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 499 goto fail; 500 } 501 502 /* Current setup has one doorbell GPIO that does both doorbell 503 * and ack. GPIOs are at 0x50, best would be to find that out 504 * in the device-tree though. 505 */ 506 smu->doorbell = *data; 507 if (smu->doorbell < 0x50) 508 smu->doorbell += 0x50; 509 510 /* Now look for the smu-interrupt GPIO */ 511 do { 512 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt"); 513 if (smu->msg_node == NULL) 514 break; 515 data = of_get_property(smu->msg_node, "reg", NULL); 516 if (data == NULL) { 517 of_node_put(smu->msg_node); 518 smu->msg_node = NULL; 519 break; 520 } 521 smu->msg = *data; 522 if (smu->msg < 0x50) 523 smu->msg += 0x50; 524 } while(0); 525 526 /* Doorbell buffer is currently hard-coded, I didn't find a proper 527 * device-tree entry giving the address. Best would probably to use 528 * an offset for K2 base though, but let's do it that way for now. 529 */ 530 smu->db_buf = ioremap(0x8000860c, 0x1000); 531 if (smu->db_buf == NULL) { 532 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 533 goto fail; 534 } 535 536 sys_ctrler = SYS_CTRLER_SMU; 537 return 0; 538 539 fail: 540 smu = NULL; 541 return -ENXIO; 542 543 } 544 545 546 static int smu_late_init(void) 547 { 548 if (!smu) 549 return 0; 550 551 init_timer(&smu->i2c_timer); 552 smu->i2c_timer.function = smu_i2c_retry; 553 smu->i2c_timer.data = (unsigned long)smu; 554 555 if (smu->db_node) { 556 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); 557 if (smu->db_irq == NO_IRQ) 558 printk(KERN_ERR "smu: failed to map irq for node %s\n", 559 smu->db_node->full_name); 560 } 561 if (smu->msg_node) { 562 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); 563 if (smu->msg_irq == NO_IRQ) 564 printk(KERN_ERR "smu: failed to map irq for node %s\n", 565 smu->msg_node->full_name); 566 } 567 568 /* 569 * Try to request the interrupts 570 */ 571 572 if (smu->db_irq != NO_IRQ) { 573 if (request_irq(smu->db_irq, smu_db_intr, 574 IRQF_SHARED, "SMU doorbell", smu) < 0) { 575 printk(KERN_WARNING "SMU: can't " 576 "request interrupt %d\n", 577 smu->db_irq); 578 smu->db_irq = NO_IRQ; 579 } 580 } 581 582 if (smu->msg_irq != NO_IRQ) { 583 if (request_irq(smu->msg_irq, smu_msg_intr, 584 IRQF_SHARED, "SMU message", smu) < 0) { 585 printk(KERN_WARNING "SMU: can't " 586 "request interrupt %d\n", 587 smu->msg_irq); 588 smu->msg_irq = NO_IRQ; 589 } 590 } 591 592 smu_irq_inited = 1; 593 return 0; 594 } 595 /* This has to be before arch_initcall as the low i2c stuff relies on the 596 * above having been done before we reach arch_initcalls 597 */ 598 core_initcall(smu_late_init); 599 600 /* 601 * sysfs visibility 602 */ 603 604 static void smu_expose_childs(struct work_struct *unused) 605 { 606 struct device_node *np; 607 608 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 609 if (of_device_is_compatible(np, "smu-sensors")) 610 of_platform_device_create(np, "smu-sensors", 611 &smu->of_dev->dev); 612 } 613 614 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 615 616 static int smu_platform_probe(struct of_device* dev, 617 const struct of_device_id *match) 618 { 619 if (!smu) 620 return -ENODEV; 621 smu->of_dev = dev; 622 623 /* 624 * Ok, we are matched, now expose all i2c busses. We have to defer 625 * that unfortunately or it would deadlock inside the device model 626 */ 627 schedule_work(&smu_expose_childs_work); 628 629 return 0; 630 } 631 632 static struct of_device_id smu_platform_match[] = 633 { 634 { 635 .type = "smu", 636 }, 637 {}, 638 }; 639 640 static struct of_platform_driver smu_of_platform_driver = 641 { 642 .name = "smu", 643 .match_table = smu_platform_match, 644 .probe = smu_platform_probe, 645 }; 646 647 static int __init smu_init_sysfs(void) 648 { 649 /* 650 * Due to sysfs bogosity, a sysdev is not a real device, so 651 * we should in fact create both if we want sysdev semantics 652 * for power management. 653 * For now, we don't power manage machines with an SMU chip, 654 * I'm a bit too far from figuring out how that works with those 655 * new chipsets, but that will come back and bite us 656 */ 657 of_register_platform_driver(&smu_of_platform_driver); 658 return 0; 659 } 660 661 device_initcall(smu_init_sysfs); 662 663 struct of_device *smu_get_ofdev(void) 664 { 665 if (!smu) 666 return NULL; 667 return smu->of_dev; 668 } 669 670 EXPORT_SYMBOL_GPL(smu_get_ofdev); 671 672 /* 673 * i2c interface 674 */ 675 676 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 677 { 678 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 679 void *misc = cmd->misc; 680 unsigned long flags; 681 682 /* Check for read case */ 683 if (!fail && cmd->read) { 684 if (cmd->pdata[0] < 1) 685 fail = 1; 686 else 687 memcpy(cmd->info.data, &cmd->pdata[1], 688 cmd->info.datalen); 689 } 690 691 DPRINTK("SMU: completing, success: %d\n", !fail); 692 693 /* Update status and mark no pending i2c command with lock 694 * held so nobody comes in while we dequeue an eventual 695 * pending next i2c command 696 */ 697 spin_lock_irqsave(&smu->lock, flags); 698 smu->cmd_i2c_cur = NULL; 699 wmb(); 700 cmd->status = fail ? -EIO : 0; 701 702 /* Is there another i2c command waiting ? */ 703 if (!list_empty(&smu->cmd_i2c_list)) { 704 struct smu_i2c_cmd *newcmd; 705 706 /* Fetch it, new current, remove from list */ 707 newcmd = list_entry(smu->cmd_i2c_list.next, 708 struct smu_i2c_cmd, link); 709 smu->cmd_i2c_cur = newcmd; 710 list_del(&cmd->link); 711 712 /* Queue with low level smu */ 713 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 714 if (smu->cmd_cur == NULL) 715 smu_start_cmd(); 716 } 717 spin_unlock_irqrestore(&smu->lock, flags); 718 719 /* Call command completion handler if any */ 720 if (done) 721 done(cmd, misc); 722 723 } 724 725 726 static void smu_i2c_retry(unsigned long data) 727 { 728 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 729 730 DPRINTK("SMU: i2c failure, requeuing...\n"); 731 732 /* requeue command simply by resetting reply_len */ 733 cmd->pdata[0] = 0xff; 734 cmd->scmd.reply_len = sizeof(cmd->pdata); 735 smu_queue_cmd(&cmd->scmd); 736 } 737 738 739 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 740 { 741 struct smu_i2c_cmd *cmd = misc; 742 int fail = 0; 743 744 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 745 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 746 747 /* Check for possible status */ 748 if (scmd->status < 0) 749 fail = 1; 750 else if (cmd->read) { 751 if (cmd->stage == 0) 752 fail = cmd->pdata[0] != 0; 753 else 754 fail = cmd->pdata[0] >= 0x80; 755 } else { 756 fail = cmd->pdata[0] != 0; 757 } 758 759 /* Handle failures by requeuing command, after 5ms interval 760 */ 761 if (fail && --cmd->retries > 0) { 762 DPRINTK("SMU: i2c failure, starting timer...\n"); 763 BUG_ON(cmd != smu->cmd_i2c_cur); 764 if (!smu_irq_inited) { 765 mdelay(5); 766 smu_i2c_retry(0); 767 return; 768 } 769 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 770 return; 771 } 772 773 /* If failure or stage 1, command is complete */ 774 if (fail || cmd->stage != 0) { 775 smu_i2c_complete_command(cmd, fail); 776 return; 777 } 778 779 DPRINTK("SMU: going to stage 1\n"); 780 781 /* Ok, initial command complete, now poll status */ 782 scmd->reply_buf = cmd->pdata; 783 scmd->reply_len = sizeof(cmd->pdata); 784 scmd->data_buf = cmd->pdata; 785 scmd->data_len = 1; 786 cmd->pdata[0] = 0; 787 cmd->stage = 1; 788 cmd->retries = 20; 789 smu_queue_cmd(scmd); 790 } 791 792 793 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 794 { 795 unsigned long flags; 796 797 if (smu == NULL) 798 return -ENODEV; 799 800 /* Fill most fields of scmd */ 801 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 802 cmd->scmd.done = smu_i2c_low_completion; 803 cmd->scmd.misc = cmd; 804 cmd->scmd.reply_buf = cmd->pdata; 805 cmd->scmd.reply_len = sizeof(cmd->pdata); 806 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 807 cmd->scmd.status = 1; 808 cmd->stage = 0; 809 cmd->pdata[0] = 0xff; 810 cmd->retries = 20; 811 cmd->status = 1; 812 813 /* Check transfer type, sanitize some "info" fields 814 * based on transfer type and do more checking 815 */ 816 cmd->info.caddr = cmd->info.devaddr; 817 cmd->read = cmd->info.devaddr & 0x01; 818 switch(cmd->info.type) { 819 case SMU_I2C_TRANSFER_SIMPLE: 820 memset(&cmd->info.sublen, 0, 4); 821 break; 822 case SMU_I2C_TRANSFER_COMBINED: 823 cmd->info.devaddr &= 0xfe; 824 case SMU_I2C_TRANSFER_STDSUB: 825 if (cmd->info.sublen > 3) 826 return -EINVAL; 827 break; 828 default: 829 return -EINVAL; 830 } 831 832 /* Finish setting up command based on transfer direction 833 */ 834 if (cmd->read) { 835 if (cmd->info.datalen > SMU_I2C_READ_MAX) 836 return -EINVAL; 837 memset(cmd->info.data, 0xff, cmd->info.datalen); 838 cmd->scmd.data_len = 9; 839 } else { 840 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 841 return -EINVAL; 842 cmd->scmd.data_len = 9 + cmd->info.datalen; 843 } 844 845 DPRINTK("SMU: i2c enqueuing command\n"); 846 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 847 cmd->read ? "read" : "write", cmd->info.datalen, 848 cmd->info.bus, cmd->info.caddr, 849 cmd->info.subaddr[0], cmd->info.type); 850 851 852 /* Enqueue command in i2c list, and if empty, enqueue also in 853 * main command list 854 */ 855 spin_lock_irqsave(&smu->lock, flags); 856 if (smu->cmd_i2c_cur == NULL) { 857 smu->cmd_i2c_cur = cmd; 858 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 859 if (smu->cmd_cur == NULL) 860 smu_start_cmd(); 861 } else 862 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 863 spin_unlock_irqrestore(&smu->lock, flags); 864 865 return 0; 866 } 867 868 /* 869 * Handling of "partitions" 870 */ 871 872 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 873 { 874 DECLARE_COMPLETION_ONSTACK(comp); 875 unsigned int chunk; 876 struct smu_cmd cmd; 877 int rc; 878 u8 params[8]; 879 880 /* We currently use a chunk size of 0xe. We could check the 881 * SMU firmware version and use bigger sizes though 882 */ 883 chunk = 0xe; 884 885 while (len) { 886 unsigned int clen = min(len, chunk); 887 888 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 889 cmd.data_len = 7; 890 cmd.data_buf = params; 891 cmd.reply_len = chunk; 892 cmd.reply_buf = dest; 893 cmd.done = smu_done_complete; 894 cmd.misc = ∁ 895 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 896 params[1] = 0x4; 897 *((u32 *)¶ms[2]) = addr; 898 params[6] = clen; 899 900 rc = smu_queue_cmd(&cmd); 901 if (rc) 902 return rc; 903 wait_for_completion(&comp); 904 if (cmd.status != 0) 905 return rc; 906 if (cmd.reply_len != clen) { 907 printk(KERN_DEBUG "SMU: short read in " 908 "smu_read_datablock, got: %d, want: %d\n", 909 cmd.reply_len, clen); 910 return -EIO; 911 } 912 len -= clen; 913 addr += clen; 914 dest += clen; 915 } 916 return 0; 917 } 918 919 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 920 { 921 DECLARE_COMPLETION_ONSTACK(comp); 922 struct smu_simple_cmd cmd; 923 unsigned int addr, len, tlen; 924 struct smu_sdbp_header *hdr; 925 struct property *prop; 926 927 /* First query the partition info */ 928 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 929 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 930 smu_done_complete, &comp, 931 SMU_CMD_PARTITION_LATEST, id); 932 wait_for_completion(&comp); 933 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 934 cmd.cmd.status, cmd.cmd.reply_len); 935 936 /* Partition doesn't exist (or other error) */ 937 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 938 return NULL; 939 940 /* Fetch address and length from reply */ 941 addr = *((u16 *)cmd.buffer); 942 len = cmd.buffer[3] << 2; 943 /* Calucluate total length to allocate, including the 17 bytes 944 * for "sdb-partition-XX" that we append at the end of the buffer 945 */ 946 tlen = sizeof(struct property) + len + 18; 947 948 prop = kzalloc(tlen, GFP_KERNEL); 949 if (prop == NULL) 950 return NULL; 951 hdr = (struct smu_sdbp_header *)(prop + 1); 952 prop->name = ((char *)prop) + tlen - 18; 953 sprintf(prop->name, "sdb-partition-%02x", id); 954 prop->length = len; 955 prop->value = hdr; 956 prop->next = NULL; 957 958 /* Read the datablock */ 959 if (smu_read_datablock((u8 *)hdr, addr, len)) { 960 printk(KERN_DEBUG "SMU: datablock read failed while reading " 961 "partition %02x !\n", id); 962 goto failure; 963 } 964 965 /* Got it, check a few things and create the property */ 966 if (hdr->id != id) { 967 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 968 "%02x !\n", id, hdr->id); 969 goto failure; 970 } 971 if (prom_add_property(smu->of_node, prop)) { 972 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 973 "property !\n", id); 974 goto failure; 975 } 976 977 return hdr; 978 failure: 979 kfree(prop); 980 return NULL; 981 } 982 983 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 984 * when interruptible is 1 985 */ 986 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 987 unsigned int *size, int interruptible) 988 { 989 char pname[32]; 990 const struct smu_sdbp_header *part; 991 992 if (!smu) 993 return NULL; 994 995 sprintf(pname, "sdb-partition-%02x", id); 996 997 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 998 999 if (interruptible) { 1000 int rc; 1001 rc = mutex_lock_interruptible(&smu_part_access); 1002 if (rc) 1003 return ERR_PTR(rc); 1004 } else 1005 mutex_lock(&smu_part_access); 1006 1007 part = of_get_property(smu->of_node, pname, size); 1008 if (part == NULL) { 1009 DPRINTK("trying to extract from SMU ...\n"); 1010 part = smu_create_sdb_partition(id); 1011 if (part != NULL && size) 1012 *size = part->len << 2; 1013 } 1014 mutex_unlock(&smu_part_access); 1015 return part; 1016 } 1017 1018 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1019 { 1020 return __smu_get_sdb_partition(id, size, 0); 1021 } 1022 EXPORT_SYMBOL(smu_get_sdb_partition); 1023 1024 1025 /* 1026 * Userland driver interface 1027 */ 1028 1029 1030 static LIST_HEAD(smu_clist); 1031 static DEFINE_SPINLOCK(smu_clist_lock); 1032 1033 enum smu_file_mode { 1034 smu_file_commands, 1035 smu_file_events, 1036 smu_file_closing 1037 }; 1038 1039 struct smu_private 1040 { 1041 struct list_head list; 1042 enum smu_file_mode mode; 1043 int busy; 1044 struct smu_cmd cmd; 1045 spinlock_t lock; 1046 wait_queue_head_t wait; 1047 u8 buffer[SMU_MAX_DATA]; 1048 }; 1049 1050 1051 static int smu_open(struct inode *inode, struct file *file) 1052 { 1053 struct smu_private *pp; 1054 unsigned long flags; 1055 1056 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1057 if (pp == 0) 1058 return -ENOMEM; 1059 spin_lock_init(&pp->lock); 1060 pp->mode = smu_file_commands; 1061 init_waitqueue_head(&pp->wait); 1062 1063 spin_lock_irqsave(&smu_clist_lock, flags); 1064 list_add(&pp->list, &smu_clist); 1065 spin_unlock_irqrestore(&smu_clist_lock, flags); 1066 file->private_data = pp; 1067 1068 return 0; 1069 } 1070 1071 1072 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1073 { 1074 struct smu_private *pp = misc; 1075 1076 wake_up_all(&pp->wait); 1077 } 1078 1079 1080 static ssize_t smu_write(struct file *file, const char __user *buf, 1081 size_t count, loff_t *ppos) 1082 { 1083 struct smu_private *pp = file->private_data; 1084 unsigned long flags; 1085 struct smu_user_cmd_hdr hdr; 1086 int rc = 0; 1087 1088 if (pp->busy) 1089 return -EBUSY; 1090 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1091 return -EFAULT; 1092 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1093 pp->mode = smu_file_events; 1094 return 0; 1095 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1096 const struct smu_sdbp_header *part; 1097 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1098 if (part == NULL) 1099 return -EINVAL; 1100 else if (IS_ERR(part)) 1101 return PTR_ERR(part); 1102 return 0; 1103 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1104 return -EINVAL; 1105 else if (pp->mode != smu_file_commands) 1106 return -EBADFD; 1107 else if (hdr.data_len > SMU_MAX_DATA) 1108 return -EINVAL; 1109 1110 spin_lock_irqsave(&pp->lock, flags); 1111 if (pp->busy) { 1112 spin_unlock_irqrestore(&pp->lock, flags); 1113 return -EBUSY; 1114 } 1115 pp->busy = 1; 1116 pp->cmd.status = 1; 1117 spin_unlock_irqrestore(&pp->lock, flags); 1118 1119 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1120 pp->busy = 0; 1121 return -EFAULT; 1122 } 1123 1124 pp->cmd.cmd = hdr.cmd; 1125 pp->cmd.data_len = hdr.data_len; 1126 pp->cmd.reply_len = SMU_MAX_DATA; 1127 pp->cmd.data_buf = pp->buffer; 1128 pp->cmd.reply_buf = pp->buffer; 1129 pp->cmd.done = smu_user_cmd_done; 1130 pp->cmd.misc = pp; 1131 rc = smu_queue_cmd(&pp->cmd); 1132 if (rc < 0) 1133 return rc; 1134 return count; 1135 } 1136 1137 1138 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1139 char __user *buf, size_t count) 1140 { 1141 DECLARE_WAITQUEUE(wait, current); 1142 struct smu_user_reply_hdr hdr; 1143 unsigned long flags; 1144 int size, rc = 0; 1145 1146 if (!pp->busy) 1147 return 0; 1148 if (count < sizeof(struct smu_user_reply_hdr)) 1149 return -EOVERFLOW; 1150 spin_lock_irqsave(&pp->lock, flags); 1151 if (pp->cmd.status == 1) { 1152 if (file->f_flags & O_NONBLOCK) 1153 return -EAGAIN; 1154 add_wait_queue(&pp->wait, &wait); 1155 for (;;) { 1156 set_current_state(TASK_INTERRUPTIBLE); 1157 rc = 0; 1158 if (pp->cmd.status != 1) 1159 break; 1160 rc = -ERESTARTSYS; 1161 if (signal_pending(current)) 1162 break; 1163 spin_unlock_irqrestore(&pp->lock, flags); 1164 schedule(); 1165 spin_lock_irqsave(&pp->lock, flags); 1166 } 1167 set_current_state(TASK_RUNNING); 1168 remove_wait_queue(&pp->wait, &wait); 1169 } 1170 spin_unlock_irqrestore(&pp->lock, flags); 1171 if (rc) 1172 return rc; 1173 if (pp->cmd.status != 0) 1174 pp->cmd.reply_len = 0; 1175 size = sizeof(hdr) + pp->cmd.reply_len; 1176 if (count < size) 1177 size = count; 1178 rc = size; 1179 hdr.status = pp->cmd.status; 1180 hdr.reply_len = pp->cmd.reply_len; 1181 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1182 return -EFAULT; 1183 size -= sizeof(hdr); 1184 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1185 return -EFAULT; 1186 pp->busy = 0; 1187 1188 return rc; 1189 } 1190 1191 1192 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1193 char __user *buf, size_t count) 1194 { 1195 /* Not implemented */ 1196 msleep_interruptible(1000); 1197 return 0; 1198 } 1199 1200 1201 static ssize_t smu_read(struct file *file, char __user *buf, 1202 size_t count, loff_t *ppos) 1203 { 1204 struct smu_private *pp = file->private_data; 1205 1206 if (pp->mode == smu_file_commands) 1207 return smu_read_command(file, pp, buf, count); 1208 if (pp->mode == smu_file_events) 1209 return smu_read_events(file, pp, buf, count); 1210 1211 return -EBADFD; 1212 } 1213 1214 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1215 { 1216 struct smu_private *pp = file->private_data; 1217 unsigned int mask = 0; 1218 unsigned long flags; 1219 1220 if (pp == 0) 1221 return 0; 1222 1223 if (pp->mode == smu_file_commands) { 1224 poll_wait(file, &pp->wait, wait); 1225 1226 spin_lock_irqsave(&pp->lock, flags); 1227 if (pp->busy && pp->cmd.status != 1) 1228 mask |= POLLIN; 1229 spin_unlock_irqrestore(&pp->lock, flags); 1230 } if (pp->mode == smu_file_events) { 1231 /* Not yet implemented */ 1232 } 1233 return mask; 1234 } 1235 1236 static int smu_release(struct inode *inode, struct file *file) 1237 { 1238 struct smu_private *pp = file->private_data; 1239 unsigned long flags; 1240 unsigned int busy; 1241 1242 if (pp == 0) 1243 return 0; 1244 1245 file->private_data = NULL; 1246 1247 /* Mark file as closing to avoid races with new request */ 1248 spin_lock_irqsave(&pp->lock, flags); 1249 pp->mode = smu_file_closing; 1250 busy = pp->busy; 1251 1252 /* Wait for any pending request to complete */ 1253 if (busy && pp->cmd.status == 1) { 1254 DECLARE_WAITQUEUE(wait, current); 1255 1256 add_wait_queue(&pp->wait, &wait); 1257 for (;;) { 1258 set_current_state(TASK_UNINTERRUPTIBLE); 1259 if (pp->cmd.status != 1) 1260 break; 1261 spin_unlock_irqrestore(&pp->lock, flags); 1262 schedule(); 1263 spin_lock_irqsave(&pp->lock, flags); 1264 } 1265 set_current_state(TASK_RUNNING); 1266 remove_wait_queue(&pp->wait, &wait); 1267 } 1268 spin_unlock_irqrestore(&pp->lock, flags); 1269 1270 spin_lock_irqsave(&smu_clist_lock, flags); 1271 list_del(&pp->list); 1272 spin_unlock_irqrestore(&smu_clist_lock, flags); 1273 kfree(pp); 1274 1275 return 0; 1276 } 1277 1278 1279 static const struct file_operations smu_device_fops = { 1280 .llseek = no_llseek, 1281 .read = smu_read, 1282 .write = smu_write, 1283 .poll = smu_fpoll, 1284 .open = smu_open, 1285 .release = smu_release, 1286 }; 1287 1288 static struct miscdevice pmu_device = { 1289 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1290 }; 1291 1292 static int smu_device_init(void) 1293 { 1294 if (!smu) 1295 return -ENODEV; 1296 if (misc_register(&pmu_device) < 0) 1297 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1298 return 0; 1299 } 1300 device_initcall(smu_device_init); 1301