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 * interrupts 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 int broken_nap; 89 struct list_head cmd_i2c_list; 90 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 91 struct timer_list i2c_timer; 92 }; 93 94 /* 95 * I don't think there will ever be more than one SMU, so 96 * for now, just hard code that 97 */ 98 static struct smu_device *smu; 99 static DEFINE_MUTEX(smu_part_access); 100 static int smu_irq_inited; 101 102 static void smu_i2c_retry(unsigned long data); 103 104 /* 105 * SMU driver low level stuff 106 */ 107 108 static void smu_start_cmd(void) 109 { 110 unsigned long faddr, fend; 111 struct smu_cmd *cmd; 112 113 if (list_empty(&smu->cmd_list)) 114 return; 115 116 /* Fetch first command in queue */ 117 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 118 smu->cmd_cur = cmd; 119 list_del(&cmd->link); 120 121 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 122 cmd->data_len); 123 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 124 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 125 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 126 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 127 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 128 129 /* Fill the SMU command buffer */ 130 smu->cmd_buf->cmd = cmd->cmd; 131 smu->cmd_buf->length = cmd->data_len; 132 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 133 134 /* Flush command and data to RAM */ 135 faddr = (unsigned long)smu->cmd_buf; 136 fend = faddr + smu->cmd_buf->length + 2; 137 flush_inval_dcache_range(faddr, fend); 138 139 140 /* We also disable NAP mode for the duration of the command 141 * on U3 based machines. 142 * This is slightly racy as it can be written back to 1 by a sysctl 143 * but that never happens in practice. There seem to be an issue with 144 * U3 based machines such as the iMac G5 where napping for the 145 * whole duration of the command prevents the SMU from fetching it 146 * from memory. This might be related to the strange i2c based 147 * mechanism the SMU uses to access memory. 148 */ 149 if (smu->broken_nap) 150 powersave_nap = 0; 151 152 /* This isn't exactly a DMA mapping here, I suspect 153 * the SMU is actually communicating with us via i2c to the 154 * northbridge or the CPU to access RAM. 155 */ 156 writel(smu->cmd_buf_abs, smu->db_buf); 157 158 /* Ring the SMU doorbell */ 159 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 160 } 161 162 163 static irqreturn_t smu_db_intr(int irq, void *arg) 164 { 165 unsigned long flags; 166 struct smu_cmd *cmd; 167 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 168 void *misc = NULL; 169 u8 gpio; 170 int rc = 0; 171 172 /* SMU completed the command, well, we hope, let's make sure 173 * of it 174 */ 175 spin_lock_irqsave(&smu->lock, flags); 176 177 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 178 if ((gpio & 7) != 7) { 179 spin_unlock_irqrestore(&smu->lock, flags); 180 return IRQ_HANDLED; 181 } 182 183 cmd = smu->cmd_cur; 184 smu->cmd_cur = NULL; 185 if (cmd == NULL) 186 goto bail; 187 188 if (rc == 0) { 189 unsigned long faddr; 190 int reply_len; 191 u8 ack; 192 193 /* CPU might have brought back the cache line, so we need 194 * to flush again before peeking at the SMU response. We 195 * flush the entire buffer for now as we haven't read the 196 * reply length (it's only 2 cache lines anyway) 197 */ 198 faddr = (unsigned long)smu->cmd_buf; 199 flush_inval_dcache_range(faddr, faddr + 256); 200 201 /* Now check ack */ 202 ack = (~cmd->cmd) & 0xff; 203 if (ack != smu->cmd_buf->cmd) { 204 DPRINTK("SMU: incorrect ack, want %x got %x\n", 205 ack, smu->cmd_buf->cmd); 206 rc = -EIO; 207 } 208 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 209 DPRINTK("SMU: reply len: %d\n", reply_len); 210 if (reply_len > cmd->reply_len) { 211 printk(KERN_WARNING "SMU: reply buffer too small," 212 "got %d bytes for a %d bytes buffer\n", 213 reply_len, cmd->reply_len); 214 reply_len = cmd->reply_len; 215 } 216 cmd->reply_len = reply_len; 217 if (cmd->reply_buf && reply_len) 218 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 219 } 220 221 /* Now complete the command. Write status last in order as we lost 222 * ownership of the command structure as soon as it's no longer -1 223 */ 224 done = cmd->done; 225 misc = cmd->misc; 226 mb(); 227 cmd->status = rc; 228 229 /* Re-enable NAP mode */ 230 if (smu->broken_nap) 231 powersave_nap = 1; 232 bail: 233 /* Start next command if any */ 234 smu_start_cmd(); 235 spin_unlock_irqrestore(&smu->lock, flags); 236 237 /* Call command completion handler if any */ 238 if (done) 239 done(cmd, misc); 240 241 /* It's an edge interrupt, nothing to do */ 242 return IRQ_HANDLED; 243 } 244 245 246 static irqreturn_t smu_msg_intr(int irq, void *arg) 247 { 248 /* I don't quite know what to do with this one, we seem to never 249 * receive it, so I suspect we have to arm it someway in the SMU 250 * to start getting events that way. 251 */ 252 253 printk(KERN_INFO "SMU: message interrupt !\n"); 254 255 /* It's an edge interrupt, nothing to do */ 256 return IRQ_HANDLED; 257 } 258 259 260 /* 261 * Queued command management. 262 * 263 */ 264 265 int smu_queue_cmd(struct smu_cmd *cmd) 266 { 267 unsigned long flags; 268 269 if (smu == NULL) 270 return -ENODEV; 271 if (cmd->data_len > SMU_MAX_DATA || 272 cmd->reply_len > SMU_MAX_DATA) 273 return -EINVAL; 274 275 cmd->status = 1; 276 spin_lock_irqsave(&smu->lock, flags); 277 list_add_tail(&cmd->link, &smu->cmd_list); 278 if (smu->cmd_cur == NULL) 279 smu_start_cmd(); 280 spin_unlock_irqrestore(&smu->lock, flags); 281 282 /* Workaround for early calls when irq isn't available */ 283 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 284 smu_spinwait_cmd(cmd); 285 286 return 0; 287 } 288 EXPORT_SYMBOL(smu_queue_cmd); 289 290 291 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 292 unsigned int data_len, 293 void (*done)(struct smu_cmd *cmd, void *misc), 294 void *misc, ...) 295 { 296 struct smu_cmd *cmd = &scmd->cmd; 297 va_list list; 298 int i; 299 300 if (data_len > sizeof(scmd->buffer)) 301 return -EINVAL; 302 303 memset(scmd, 0, sizeof(*scmd)); 304 cmd->cmd = command; 305 cmd->data_len = data_len; 306 cmd->data_buf = scmd->buffer; 307 cmd->reply_len = sizeof(scmd->buffer); 308 cmd->reply_buf = scmd->buffer; 309 cmd->done = done; 310 cmd->misc = misc; 311 312 va_start(list, misc); 313 for (i = 0; i < data_len; ++i) 314 scmd->buffer[i] = (u8)va_arg(list, int); 315 va_end(list); 316 317 return smu_queue_cmd(cmd); 318 } 319 EXPORT_SYMBOL(smu_queue_simple); 320 321 322 void smu_poll(void) 323 { 324 u8 gpio; 325 326 if (smu == NULL) 327 return; 328 329 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 330 if ((gpio & 7) == 7) 331 smu_db_intr(smu->db_irq, smu); 332 } 333 EXPORT_SYMBOL(smu_poll); 334 335 336 void smu_done_complete(struct smu_cmd *cmd, void *misc) 337 { 338 struct completion *comp = misc; 339 340 complete(comp); 341 } 342 EXPORT_SYMBOL(smu_done_complete); 343 344 345 void smu_spinwait_cmd(struct smu_cmd *cmd) 346 { 347 while(cmd->status == 1) 348 smu_poll(); 349 } 350 EXPORT_SYMBOL(smu_spinwait_cmd); 351 352 353 /* RTC low level commands */ 354 static inline int bcd2hex (int n) 355 { 356 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 357 } 358 359 360 static inline int hex2bcd (int n) 361 { 362 return ((n / 10) << 4) + (n % 10); 363 } 364 365 366 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 367 struct rtc_time *time) 368 { 369 cmd_buf->cmd = 0x8e; 370 cmd_buf->length = 8; 371 cmd_buf->data[0] = 0x80; 372 cmd_buf->data[1] = hex2bcd(time->tm_sec); 373 cmd_buf->data[2] = hex2bcd(time->tm_min); 374 cmd_buf->data[3] = hex2bcd(time->tm_hour); 375 cmd_buf->data[4] = time->tm_wday; 376 cmd_buf->data[5] = hex2bcd(time->tm_mday); 377 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 378 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 379 } 380 381 382 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 383 { 384 struct smu_simple_cmd cmd; 385 int rc; 386 387 if (smu == NULL) 388 return -ENODEV; 389 390 memset(time, 0, sizeof(struct rtc_time)); 391 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 392 SMU_CMD_RTC_GET_DATETIME); 393 if (rc) 394 return rc; 395 smu_spinwait_simple(&cmd); 396 397 time->tm_sec = bcd2hex(cmd.buffer[0]); 398 time->tm_min = bcd2hex(cmd.buffer[1]); 399 time->tm_hour = bcd2hex(cmd.buffer[2]); 400 time->tm_wday = bcd2hex(cmd.buffer[3]); 401 time->tm_mday = bcd2hex(cmd.buffer[4]); 402 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 403 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 404 405 return 0; 406 } 407 408 409 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 410 { 411 struct smu_simple_cmd cmd; 412 int rc; 413 414 if (smu == NULL) 415 return -ENODEV; 416 417 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 418 SMU_CMD_RTC_SET_DATETIME, 419 hex2bcd(time->tm_sec), 420 hex2bcd(time->tm_min), 421 hex2bcd(time->tm_hour), 422 time->tm_wday, 423 hex2bcd(time->tm_mday), 424 hex2bcd(time->tm_mon) + 1, 425 hex2bcd(time->tm_year - 100)); 426 if (rc) 427 return rc; 428 smu_spinwait_simple(&cmd); 429 430 return 0; 431 } 432 433 434 void smu_shutdown(void) 435 { 436 struct smu_simple_cmd cmd; 437 438 if (smu == NULL) 439 return; 440 441 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 442 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 443 return; 444 smu_spinwait_simple(&cmd); 445 for (;;) 446 ; 447 } 448 449 450 void smu_restart(void) 451 { 452 struct smu_simple_cmd cmd; 453 454 if (smu == NULL) 455 return; 456 457 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 458 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 459 return; 460 smu_spinwait_simple(&cmd); 461 for (;;) 462 ; 463 } 464 465 466 int smu_present(void) 467 { 468 return smu != NULL; 469 } 470 EXPORT_SYMBOL(smu_present); 471 472 473 int __init smu_init (void) 474 { 475 struct device_node *np; 476 const u32 *data; 477 478 np = of_find_node_by_type(NULL, "smu"); 479 if (np == NULL) 480 return -ENODEV; 481 482 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR); 483 484 if (smu_cmdbuf_abs == 0) { 485 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 486 return -EINVAL; 487 } 488 489 smu = alloc_bootmem(sizeof(struct smu_device)); 490 if (smu == NULL) 491 return -ENOMEM; 492 memset(smu, 0, sizeof(*smu)); 493 494 spin_lock_init(&smu->lock); 495 INIT_LIST_HEAD(&smu->cmd_list); 496 INIT_LIST_HEAD(&smu->cmd_i2c_list); 497 smu->of_node = np; 498 smu->db_irq = NO_IRQ; 499 smu->msg_irq = NO_IRQ; 500 501 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 502 * 32 bits value safely 503 */ 504 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 505 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); 506 507 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell"); 508 if (smu->db_node == NULL) { 509 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 510 goto fail; 511 } 512 data = of_get_property(smu->db_node, "reg", NULL); 513 if (data == NULL) { 514 of_node_put(smu->db_node); 515 smu->db_node = NULL; 516 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 517 goto fail; 518 } 519 520 /* Current setup has one doorbell GPIO that does both doorbell 521 * and ack. GPIOs are at 0x50, best would be to find that out 522 * in the device-tree though. 523 */ 524 smu->doorbell = *data; 525 if (smu->doorbell < 0x50) 526 smu->doorbell += 0x50; 527 528 /* Now look for the smu-interrupt GPIO */ 529 do { 530 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt"); 531 if (smu->msg_node == NULL) 532 break; 533 data = of_get_property(smu->msg_node, "reg", NULL); 534 if (data == NULL) { 535 of_node_put(smu->msg_node); 536 smu->msg_node = NULL; 537 break; 538 } 539 smu->msg = *data; 540 if (smu->msg < 0x50) 541 smu->msg += 0x50; 542 } while(0); 543 544 /* Doorbell buffer is currently hard-coded, I didn't find a proper 545 * device-tree entry giving the address. Best would probably to use 546 * an offset for K2 base though, but let's do it that way for now. 547 */ 548 smu->db_buf = ioremap(0x8000860c, 0x1000); 549 if (smu->db_buf == NULL) { 550 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 551 goto fail; 552 } 553 554 /* U3 has an issue with NAP mode when issuing SMU commands */ 555 smu->broken_nap = pmac_get_uninorth_variant() < 4; 556 if (smu->broken_nap) 557 printk(KERN_INFO "SMU: using NAP mode workaround\n"); 558 559 sys_ctrler = SYS_CTRLER_SMU; 560 return 0; 561 562 fail: 563 smu = NULL; 564 return -ENXIO; 565 566 } 567 568 569 static int smu_late_init(void) 570 { 571 if (!smu) 572 return 0; 573 574 init_timer(&smu->i2c_timer); 575 smu->i2c_timer.function = smu_i2c_retry; 576 smu->i2c_timer.data = (unsigned long)smu; 577 578 if (smu->db_node) { 579 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); 580 if (smu->db_irq == NO_IRQ) 581 printk(KERN_ERR "smu: failed to map irq for node %s\n", 582 smu->db_node->full_name); 583 } 584 if (smu->msg_node) { 585 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); 586 if (smu->msg_irq == NO_IRQ) 587 printk(KERN_ERR "smu: failed to map irq for node %s\n", 588 smu->msg_node->full_name); 589 } 590 591 /* 592 * Try to request the interrupts 593 */ 594 595 if (smu->db_irq != NO_IRQ) { 596 if (request_irq(smu->db_irq, smu_db_intr, 597 IRQF_SHARED, "SMU doorbell", smu) < 0) { 598 printk(KERN_WARNING "SMU: can't " 599 "request interrupt %d\n", 600 smu->db_irq); 601 smu->db_irq = NO_IRQ; 602 } 603 } 604 605 if (smu->msg_irq != NO_IRQ) { 606 if (request_irq(smu->msg_irq, smu_msg_intr, 607 IRQF_SHARED, "SMU message", smu) < 0) { 608 printk(KERN_WARNING "SMU: can't " 609 "request interrupt %d\n", 610 smu->msg_irq); 611 smu->msg_irq = NO_IRQ; 612 } 613 } 614 615 smu_irq_inited = 1; 616 return 0; 617 } 618 /* This has to be before arch_initcall as the low i2c stuff relies on the 619 * above having been done before we reach arch_initcalls 620 */ 621 core_initcall(smu_late_init); 622 623 /* 624 * sysfs visibility 625 */ 626 627 static void smu_expose_childs(struct work_struct *unused) 628 { 629 struct device_node *np; 630 631 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 632 if (of_device_is_compatible(np, "smu-sensors")) 633 of_platform_device_create(np, "smu-sensors", 634 &smu->of_dev->dev); 635 } 636 637 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 638 639 static int smu_platform_probe(struct of_device* dev, 640 const struct of_device_id *match) 641 { 642 if (!smu) 643 return -ENODEV; 644 smu->of_dev = dev; 645 646 /* 647 * Ok, we are matched, now expose all i2c busses. We have to defer 648 * that unfortunately or it would deadlock inside the device model 649 */ 650 schedule_work(&smu_expose_childs_work); 651 652 return 0; 653 } 654 655 static struct of_device_id smu_platform_match[] = 656 { 657 { 658 .type = "smu", 659 }, 660 {}, 661 }; 662 663 static struct of_platform_driver smu_of_platform_driver = 664 { 665 .name = "smu", 666 .match_table = smu_platform_match, 667 .probe = smu_platform_probe, 668 }; 669 670 static int __init smu_init_sysfs(void) 671 { 672 /* 673 * Due to sysfs bogosity, a sysdev is not a real device, so 674 * we should in fact create both if we want sysdev semantics 675 * for power management. 676 * For now, we don't power manage machines with an SMU chip, 677 * I'm a bit too far from figuring out how that works with those 678 * new chipsets, but that will come back and bite us 679 */ 680 of_register_platform_driver(&smu_of_platform_driver); 681 return 0; 682 } 683 684 device_initcall(smu_init_sysfs); 685 686 struct of_device *smu_get_ofdev(void) 687 { 688 if (!smu) 689 return NULL; 690 return smu->of_dev; 691 } 692 693 EXPORT_SYMBOL_GPL(smu_get_ofdev); 694 695 /* 696 * i2c interface 697 */ 698 699 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 700 { 701 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 702 void *misc = cmd->misc; 703 unsigned long flags; 704 705 /* Check for read case */ 706 if (!fail && cmd->read) { 707 if (cmd->pdata[0] < 1) 708 fail = 1; 709 else 710 memcpy(cmd->info.data, &cmd->pdata[1], 711 cmd->info.datalen); 712 } 713 714 DPRINTK("SMU: completing, success: %d\n", !fail); 715 716 /* Update status and mark no pending i2c command with lock 717 * held so nobody comes in while we dequeue an eventual 718 * pending next i2c command 719 */ 720 spin_lock_irqsave(&smu->lock, flags); 721 smu->cmd_i2c_cur = NULL; 722 wmb(); 723 cmd->status = fail ? -EIO : 0; 724 725 /* Is there another i2c command waiting ? */ 726 if (!list_empty(&smu->cmd_i2c_list)) { 727 struct smu_i2c_cmd *newcmd; 728 729 /* Fetch it, new current, remove from list */ 730 newcmd = list_entry(smu->cmd_i2c_list.next, 731 struct smu_i2c_cmd, link); 732 smu->cmd_i2c_cur = newcmd; 733 list_del(&cmd->link); 734 735 /* Queue with low level smu */ 736 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 737 if (smu->cmd_cur == NULL) 738 smu_start_cmd(); 739 } 740 spin_unlock_irqrestore(&smu->lock, flags); 741 742 /* Call command completion handler if any */ 743 if (done) 744 done(cmd, misc); 745 746 } 747 748 749 static void smu_i2c_retry(unsigned long data) 750 { 751 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 752 753 DPRINTK("SMU: i2c failure, requeuing...\n"); 754 755 /* requeue command simply by resetting reply_len */ 756 cmd->pdata[0] = 0xff; 757 cmd->scmd.reply_len = sizeof(cmd->pdata); 758 smu_queue_cmd(&cmd->scmd); 759 } 760 761 762 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 763 { 764 struct smu_i2c_cmd *cmd = misc; 765 int fail = 0; 766 767 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 768 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 769 770 /* Check for possible status */ 771 if (scmd->status < 0) 772 fail = 1; 773 else if (cmd->read) { 774 if (cmd->stage == 0) 775 fail = cmd->pdata[0] != 0; 776 else 777 fail = cmd->pdata[0] >= 0x80; 778 } else { 779 fail = cmd->pdata[0] != 0; 780 } 781 782 /* Handle failures by requeuing command, after 5ms interval 783 */ 784 if (fail && --cmd->retries > 0) { 785 DPRINTK("SMU: i2c failure, starting timer...\n"); 786 BUG_ON(cmd != smu->cmd_i2c_cur); 787 if (!smu_irq_inited) { 788 mdelay(5); 789 smu_i2c_retry(0); 790 return; 791 } 792 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 793 return; 794 } 795 796 /* If failure or stage 1, command is complete */ 797 if (fail || cmd->stage != 0) { 798 smu_i2c_complete_command(cmd, fail); 799 return; 800 } 801 802 DPRINTK("SMU: going to stage 1\n"); 803 804 /* Ok, initial command complete, now poll status */ 805 scmd->reply_buf = cmd->pdata; 806 scmd->reply_len = sizeof(cmd->pdata); 807 scmd->data_buf = cmd->pdata; 808 scmd->data_len = 1; 809 cmd->pdata[0] = 0; 810 cmd->stage = 1; 811 cmd->retries = 20; 812 smu_queue_cmd(scmd); 813 } 814 815 816 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 817 { 818 unsigned long flags; 819 820 if (smu == NULL) 821 return -ENODEV; 822 823 /* Fill most fields of scmd */ 824 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 825 cmd->scmd.done = smu_i2c_low_completion; 826 cmd->scmd.misc = cmd; 827 cmd->scmd.reply_buf = cmd->pdata; 828 cmd->scmd.reply_len = sizeof(cmd->pdata); 829 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 830 cmd->scmd.status = 1; 831 cmd->stage = 0; 832 cmd->pdata[0] = 0xff; 833 cmd->retries = 20; 834 cmd->status = 1; 835 836 /* Check transfer type, sanitize some "info" fields 837 * based on transfer type and do more checking 838 */ 839 cmd->info.caddr = cmd->info.devaddr; 840 cmd->read = cmd->info.devaddr & 0x01; 841 switch(cmd->info.type) { 842 case SMU_I2C_TRANSFER_SIMPLE: 843 memset(&cmd->info.sublen, 0, 4); 844 break; 845 case SMU_I2C_TRANSFER_COMBINED: 846 cmd->info.devaddr &= 0xfe; 847 case SMU_I2C_TRANSFER_STDSUB: 848 if (cmd->info.sublen > 3) 849 return -EINVAL; 850 break; 851 default: 852 return -EINVAL; 853 } 854 855 /* Finish setting up command based on transfer direction 856 */ 857 if (cmd->read) { 858 if (cmd->info.datalen > SMU_I2C_READ_MAX) 859 return -EINVAL; 860 memset(cmd->info.data, 0xff, cmd->info.datalen); 861 cmd->scmd.data_len = 9; 862 } else { 863 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 864 return -EINVAL; 865 cmd->scmd.data_len = 9 + cmd->info.datalen; 866 } 867 868 DPRINTK("SMU: i2c enqueuing command\n"); 869 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 870 cmd->read ? "read" : "write", cmd->info.datalen, 871 cmd->info.bus, cmd->info.caddr, 872 cmd->info.subaddr[0], cmd->info.type); 873 874 875 /* Enqueue command in i2c list, and if empty, enqueue also in 876 * main command list 877 */ 878 spin_lock_irqsave(&smu->lock, flags); 879 if (smu->cmd_i2c_cur == NULL) { 880 smu->cmd_i2c_cur = cmd; 881 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 882 if (smu->cmd_cur == NULL) 883 smu_start_cmd(); 884 } else 885 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 886 spin_unlock_irqrestore(&smu->lock, flags); 887 888 return 0; 889 } 890 891 /* 892 * Handling of "partitions" 893 */ 894 895 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 896 { 897 DECLARE_COMPLETION_ONSTACK(comp); 898 unsigned int chunk; 899 struct smu_cmd cmd; 900 int rc; 901 u8 params[8]; 902 903 /* We currently use a chunk size of 0xe. We could check the 904 * SMU firmware version and use bigger sizes though 905 */ 906 chunk = 0xe; 907 908 while (len) { 909 unsigned int clen = min(len, chunk); 910 911 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 912 cmd.data_len = 7; 913 cmd.data_buf = params; 914 cmd.reply_len = chunk; 915 cmd.reply_buf = dest; 916 cmd.done = smu_done_complete; 917 cmd.misc = ∁ 918 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 919 params[1] = 0x4; 920 *((u32 *)¶ms[2]) = addr; 921 params[6] = clen; 922 923 rc = smu_queue_cmd(&cmd); 924 if (rc) 925 return rc; 926 wait_for_completion(&comp); 927 if (cmd.status != 0) 928 return rc; 929 if (cmd.reply_len != clen) { 930 printk(KERN_DEBUG "SMU: short read in " 931 "smu_read_datablock, got: %d, want: %d\n", 932 cmd.reply_len, clen); 933 return -EIO; 934 } 935 len -= clen; 936 addr += clen; 937 dest += clen; 938 } 939 return 0; 940 } 941 942 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 943 { 944 DECLARE_COMPLETION_ONSTACK(comp); 945 struct smu_simple_cmd cmd; 946 unsigned int addr, len, tlen; 947 struct smu_sdbp_header *hdr; 948 struct property *prop; 949 950 /* First query the partition info */ 951 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 952 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 953 smu_done_complete, &comp, 954 SMU_CMD_PARTITION_LATEST, id); 955 wait_for_completion(&comp); 956 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 957 cmd.cmd.status, cmd.cmd.reply_len); 958 959 /* Partition doesn't exist (or other error) */ 960 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 961 return NULL; 962 963 /* Fetch address and length from reply */ 964 addr = *((u16 *)cmd.buffer); 965 len = cmd.buffer[3] << 2; 966 /* Calucluate total length to allocate, including the 17 bytes 967 * for "sdb-partition-XX" that we append at the end of the buffer 968 */ 969 tlen = sizeof(struct property) + len + 18; 970 971 prop = kzalloc(tlen, GFP_KERNEL); 972 if (prop == NULL) 973 return NULL; 974 hdr = (struct smu_sdbp_header *)(prop + 1); 975 prop->name = ((char *)prop) + tlen - 18; 976 sprintf(prop->name, "sdb-partition-%02x", id); 977 prop->length = len; 978 prop->value = hdr; 979 prop->next = NULL; 980 981 /* Read the datablock */ 982 if (smu_read_datablock((u8 *)hdr, addr, len)) { 983 printk(KERN_DEBUG "SMU: datablock read failed while reading " 984 "partition %02x !\n", id); 985 goto failure; 986 } 987 988 /* Got it, check a few things and create the property */ 989 if (hdr->id != id) { 990 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 991 "%02x !\n", id, hdr->id); 992 goto failure; 993 } 994 if (prom_add_property(smu->of_node, prop)) { 995 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 996 "property !\n", id); 997 goto failure; 998 } 999 1000 return hdr; 1001 failure: 1002 kfree(prop); 1003 return NULL; 1004 } 1005 1006 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 1007 * when interruptible is 1 1008 */ 1009 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 1010 unsigned int *size, int interruptible) 1011 { 1012 char pname[32]; 1013 const struct smu_sdbp_header *part; 1014 1015 if (!smu) 1016 return NULL; 1017 1018 sprintf(pname, "sdb-partition-%02x", id); 1019 1020 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 1021 1022 if (interruptible) { 1023 int rc; 1024 rc = mutex_lock_interruptible(&smu_part_access); 1025 if (rc) 1026 return ERR_PTR(rc); 1027 } else 1028 mutex_lock(&smu_part_access); 1029 1030 part = of_get_property(smu->of_node, pname, size); 1031 if (part == NULL) { 1032 DPRINTK("trying to extract from SMU ...\n"); 1033 part = smu_create_sdb_partition(id); 1034 if (part != NULL && size) 1035 *size = part->len << 2; 1036 } 1037 mutex_unlock(&smu_part_access); 1038 return part; 1039 } 1040 1041 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1042 { 1043 return __smu_get_sdb_partition(id, size, 0); 1044 } 1045 EXPORT_SYMBOL(smu_get_sdb_partition); 1046 1047 1048 /* 1049 * Userland driver interface 1050 */ 1051 1052 1053 static LIST_HEAD(smu_clist); 1054 static DEFINE_SPINLOCK(smu_clist_lock); 1055 1056 enum smu_file_mode { 1057 smu_file_commands, 1058 smu_file_events, 1059 smu_file_closing 1060 }; 1061 1062 struct smu_private 1063 { 1064 struct list_head list; 1065 enum smu_file_mode mode; 1066 int busy; 1067 struct smu_cmd cmd; 1068 spinlock_t lock; 1069 wait_queue_head_t wait; 1070 u8 buffer[SMU_MAX_DATA]; 1071 }; 1072 1073 1074 static int smu_open(struct inode *inode, struct file *file) 1075 { 1076 struct smu_private *pp; 1077 unsigned long flags; 1078 1079 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1080 if (pp == 0) 1081 return -ENOMEM; 1082 spin_lock_init(&pp->lock); 1083 pp->mode = smu_file_commands; 1084 init_waitqueue_head(&pp->wait); 1085 1086 spin_lock_irqsave(&smu_clist_lock, flags); 1087 list_add(&pp->list, &smu_clist); 1088 spin_unlock_irqrestore(&smu_clist_lock, flags); 1089 file->private_data = pp; 1090 1091 return 0; 1092 } 1093 1094 1095 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1096 { 1097 struct smu_private *pp = misc; 1098 1099 wake_up_all(&pp->wait); 1100 } 1101 1102 1103 static ssize_t smu_write(struct file *file, const char __user *buf, 1104 size_t count, loff_t *ppos) 1105 { 1106 struct smu_private *pp = file->private_data; 1107 unsigned long flags; 1108 struct smu_user_cmd_hdr hdr; 1109 int rc = 0; 1110 1111 if (pp->busy) 1112 return -EBUSY; 1113 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1114 return -EFAULT; 1115 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1116 pp->mode = smu_file_events; 1117 return 0; 1118 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1119 const struct smu_sdbp_header *part; 1120 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1121 if (part == NULL) 1122 return -EINVAL; 1123 else if (IS_ERR(part)) 1124 return PTR_ERR(part); 1125 return 0; 1126 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1127 return -EINVAL; 1128 else if (pp->mode != smu_file_commands) 1129 return -EBADFD; 1130 else if (hdr.data_len > SMU_MAX_DATA) 1131 return -EINVAL; 1132 1133 spin_lock_irqsave(&pp->lock, flags); 1134 if (pp->busy) { 1135 spin_unlock_irqrestore(&pp->lock, flags); 1136 return -EBUSY; 1137 } 1138 pp->busy = 1; 1139 pp->cmd.status = 1; 1140 spin_unlock_irqrestore(&pp->lock, flags); 1141 1142 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1143 pp->busy = 0; 1144 return -EFAULT; 1145 } 1146 1147 pp->cmd.cmd = hdr.cmd; 1148 pp->cmd.data_len = hdr.data_len; 1149 pp->cmd.reply_len = SMU_MAX_DATA; 1150 pp->cmd.data_buf = pp->buffer; 1151 pp->cmd.reply_buf = pp->buffer; 1152 pp->cmd.done = smu_user_cmd_done; 1153 pp->cmd.misc = pp; 1154 rc = smu_queue_cmd(&pp->cmd); 1155 if (rc < 0) 1156 return rc; 1157 return count; 1158 } 1159 1160 1161 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1162 char __user *buf, size_t count) 1163 { 1164 DECLARE_WAITQUEUE(wait, current); 1165 struct smu_user_reply_hdr hdr; 1166 unsigned long flags; 1167 int size, rc = 0; 1168 1169 if (!pp->busy) 1170 return 0; 1171 if (count < sizeof(struct smu_user_reply_hdr)) 1172 return -EOVERFLOW; 1173 spin_lock_irqsave(&pp->lock, flags); 1174 if (pp->cmd.status == 1) { 1175 if (file->f_flags & O_NONBLOCK) 1176 return -EAGAIN; 1177 add_wait_queue(&pp->wait, &wait); 1178 for (;;) { 1179 set_current_state(TASK_INTERRUPTIBLE); 1180 rc = 0; 1181 if (pp->cmd.status != 1) 1182 break; 1183 rc = -ERESTARTSYS; 1184 if (signal_pending(current)) 1185 break; 1186 spin_unlock_irqrestore(&pp->lock, flags); 1187 schedule(); 1188 spin_lock_irqsave(&pp->lock, flags); 1189 } 1190 set_current_state(TASK_RUNNING); 1191 remove_wait_queue(&pp->wait, &wait); 1192 } 1193 spin_unlock_irqrestore(&pp->lock, flags); 1194 if (rc) 1195 return rc; 1196 if (pp->cmd.status != 0) 1197 pp->cmd.reply_len = 0; 1198 size = sizeof(hdr) + pp->cmd.reply_len; 1199 if (count < size) 1200 size = count; 1201 rc = size; 1202 hdr.status = pp->cmd.status; 1203 hdr.reply_len = pp->cmd.reply_len; 1204 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1205 return -EFAULT; 1206 size -= sizeof(hdr); 1207 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1208 return -EFAULT; 1209 pp->busy = 0; 1210 1211 return rc; 1212 } 1213 1214 1215 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1216 char __user *buf, size_t count) 1217 { 1218 /* Not implemented */ 1219 msleep_interruptible(1000); 1220 return 0; 1221 } 1222 1223 1224 static ssize_t smu_read(struct file *file, char __user *buf, 1225 size_t count, loff_t *ppos) 1226 { 1227 struct smu_private *pp = file->private_data; 1228 1229 if (pp->mode == smu_file_commands) 1230 return smu_read_command(file, pp, buf, count); 1231 if (pp->mode == smu_file_events) 1232 return smu_read_events(file, pp, buf, count); 1233 1234 return -EBADFD; 1235 } 1236 1237 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1238 { 1239 struct smu_private *pp = file->private_data; 1240 unsigned int mask = 0; 1241 unsigned long flags; 1242 1243 if (pp == 0) 1244 return 0; 1245 1246 if (pp->mode == smu_file_commands) { 1247 poll_wait(file, &pp->wait, wait); 1248 1249 spin_lock_irqsave(&pp->lock, flags); 1250 if (pp->busy && pp->cmd.status != 1) 1251 mask |= POLLIN; 1252 spin_unlock_irqrestore(&pp->lock, flags); 1253 } if (pp->mode == smu_file_events) { 1254 /* Not yet implemented */ 1255 } 1256 return mask; 1257 } 1258 1259 static int smu_release(struct inode *inode, struct file *file) 1260 { 1261 struct smu_private *pp = file->private_data; 1262 unsigned long flags; 1263 unsigned int busy; 1264 1265 if (pp == 0) 1266 return 0; 1267 1268 file->private_data = NULL; 1269 1270 /* Mark file as closing to avoid races with new request */ 1271 spin_lock_irqsave(&pp->lock, flags); 1272 pp->mode = smu_file_closing; 1273 busy = pp->busy; 1274 1275 /* Wait for any pending request to complete */ 1276 if (busy && pp->cmd.status == 1) { 1277 DECLARE_WAITQUEUE(wait, current); 1278 1279 add_wait_queue(&pp->wait, &wait); 1280 for (;;) { 1281 set_current_state(TASK_UNINTERRUPTIBLE); 1282 if (pp->cmd.status != 1) 1283 break; 1284 spin_unlock_irqrestore(&pp->lock, flags); 1285 schedule(); 1286 spin_lock_irqsave(&pp->lock, flags); 1287 } 1288 set_current_state(TASK_RUNNING); 1289 remove_wait_queue(&pp->wait, &wait); 1290 } 1291 spin_unlock_irqrestore(&pp->lock, flags); 1292 1293 spin_lock_irqsave(&smu_clist_lock, flags); 1294 list_del(&pp->list); 1295 spin_unlock_irqrestore(&smu_clist_lock, flags); 1296 kfree(pp); 1297 1298 return 0; 1299 } 1300 1301 1302 static const struct file_operations smu_device_fops = { 1303 .llseek = no_llseek, 1304 .read = smu_read, 1305 .write = smu_write, 1306 .poll = smu_fpoll, 1307 .open = smu_open, 1308 .release = smu_release, 1309 }; 1310 1311 static struct miscdevice pmu_device = { 1312 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1313 }; 1314 1315 static int smu_device_init(void) 1316 { 1317 if (!smu) 1318 return -ENODEV; 1319 if (misc_register(&pmu_device) < 0) 1320 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1321 return 0; 1322 } 1323 device_initcall(smu_device_init); 1324