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/poll.h> 36 #include <linux/mutex.h> 37 #include <linux/of_device.h> 38 #include <linux/of_irq.h> 39 #include <linux/of_platform.h> 40 #include <linux/slab.h> 41 42 #include <asm/byteorder.h> 43 #include <asm/io.h> 44 #include <asm/prom.h> 45 #include <asm/machdep.h> 46 #include <asm/pmac_feature.h> 47 #include <asm/smu.h> 48 #include <asm/sections.h> 49 #include <asm/uaccess.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 platform_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 DEFINE_MUTEX(smu_mutex); 99 static struct smu_device *smu; 100 static DEFINE_MUTEX(smu_part_access); 101 static int smu_irq_inited; 102 103 static void smu_i2c_retry(unsigned long data); 104 105 /* 106 * SMU driver low level stuff 107 */ 108 109 static void smu_start_cmd(void) 110 { 111 unsigned long faddr, fend; 112 struct smu_cmd *cmd; 113 114 if (list_empty(&smu->cmd_list)) 115 return; 116 117 /* Fetch first command in queue */ 118 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 119 smu->cmd_cur = cmd; 120 list_del(&cmd->link); 121 122 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 123 cmd->data_len); 124 DPRINTK("SMU: data buffer: %8ph\n", cmd->data_buf); 125 126 /* Fill the SMU command buffer */ 127 smu->cmd_buf->cmd = cmd->cmd; 128 smu->cmd_buf->length = cmd->data_len; 129 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 130 131 /* Flush command and data to RAM */ 132 faddr = (unsigned long)smu->cmd_buf; 133 fend = faddr + smu->cmd_buf->length + 2; 134 flush_inval_dcache_range(faddr, fend); 135 136 137 /* We also disable NAP mode for the duration of the command 138 * on U3 based machines. 139 * This is slightly racy as it can be written back to 1 by a sysctl 140 * but that never happens in practice. There seem to be an issue with 141 * U3 based machines such as the iMac G5 where napping for the 142 * whole duration of the command prevents the SMU from fetching it 143 * from memory. This might be related to the strange i2c based 144 * mechanism the SMU uses to access memory. 145 */ 146 if (smu->broken_nap) 147 powersave_nap = 0; 148 149 /* This isn't exactly a DMA mapping here, I suspect 150 * the SMU is actually communicating with us via i2c to the 151 * northbridge or the CPU to access RAM. 152 */ 153 writel(smu->cmd_buf_abs, smu->db_buf); 154 155 /* Ring the SMU doorbell */ 156 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 157 } 158 159 160 static irqreturn_t smu_db_intr(int irq, void *arg) 161 { 162 unsigned long flags; 163 struct smu_cmd *cmd; 164 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 165 void *misc = NULL; 166 u8 gpio; 167 int rc = 0; 168 169 /* SMU completed the command, well, we hope, let's make sure 170 * of it 171 */ 172 spin_lock_irqsave(&smu->lock, flags); 173 174 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 175 if ((gpio & 7) != 7) { 176 spin_unlock_irqrestore(&smu->lock, flags); 177 return IRQ_HANDLED; 178 } 179 180 cmd = smu->cmd_cur; 181 smu->cmd_cur = NULL; 182 if (cmd == NULL) 183 goto bail; 184 185 if (rc == 0) { 186 unsigned long faddr; 187 int reply_len; 188 u8 ack; 189 190 /* CPU might have brought back the cache line, so we need 191 * to flush again before peeking at the SMU response. We 192 * flush the entire buffer for now as we haven't read the 193 * reply length (it's only 2 cache lines anyway) 194 */ 195 faddr = (unsigned long)smu->cmd_buf; 196 flush_inval_dcache_range(faddr, faddr + 256); 197 198 /* Now check ack */ 199 ack = (~cmd->cmd) & 0xff; 200 if (ack != smu->cmd_buf->cmd) { 201 DPRINTK("SMU: incorrect ack, want %x got %x\n", 202 ack, smu->cmd_buf->cmd); 203 rc = -EIO; 204 } 205 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 206 DPRINTK("SMU: reply len: %d\n", reply_len); 207 if (reply_len > cmd->reply_len) { 208 printk(KERN_WARNING "SMU: reply buffer too small," 209 "got %d bytes for a %d bytes buffer\n", 210 reply_len, cmd->reply_len); 211 reply_len = cmd->reply_len; 212 } 213 cmd->reply_len = reply_len; 214 if (cmd->reply_buf && reply_len) 215 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 216 } 217 218 /* Now complete the command. Write status last in order as we lost 219 * ownership of the command structure as soon as it's no longer -1 220 */ 221 done = cmd->done; 222 misc = cmd->misc; 223 mb(); 224 cmd->status = rc; 225 226 /* Re-enable NAP mode */ 227 if (smu->broken_nap) 228 powersave_nap = 1; 229 bail: 230 /* Start next command if any */ 231 smu_start_cmd(); 232 spin_unlock_irqrestore(&smu->lock, flags); 233 234 /* Call command completion handler if any */ 235 if (done) 236 done(cmd, misc); 237 238 /* It's an edge interrupt, nothing to do */ 239 return IRQ_HANDLED; 240 } 241 242 243 static irqreturn_t smu_msg_intr(int irq, void *arg) 244 { 245 /* I don't quite know what to do with this one, we seem to never 246 * receive it, so I suspect we have to arm it someway in the SMU 247 * to start getting events that way. 248 */ 249 250 printk(KERN_INFO "SMU: message interrupt !\n"); 251 252 /* It's an edge interrupt, nothing to do */ 253 return IRQ_HANDLED; 254 } 255 256 257 /* 258 * Queued command management. 259 * 260 */ 261 262 int smu_queue_cmd(struct smu_cmd *cmd) 263 { 264 unsigned long flags; 265 266 if (smu == NULL) 267 return -ENODEV; 268 if (cmd->data_len > SMU_MAX_DATA || 269 cmd->reply_len > SMU_MAX_DATA) 270 return -EINVAL; 271 272 cmd->status = 1; 273 spin_lock_irqsave(&smu->lock, flags); 274 list_add_tail(&cmd->link, &smu->cmd_list); 275 if (smu->cmd_cur == NULL) 276 smu_start_cmd(); 277 spin_unlock_irqrestore(&smu->lock, flags); 278 279 /* Workaround for early calls when irq isn't available */ 280 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 281 smu_spinwait_cmd(cmd); 282 283 return 0; 284 } 285 EXPORT_SYMBOL(smu_queue_cmd); 286 287 288 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 289 unsigned int data_len, 290 void (*done)(struct smu_cmd *cmd, void *misc), 291 void *misc, ...) 292 { 293 struct smu_cmd *cmd = &scmd->cmd; 294 va_list list; 295 int i; 296 297 if (data_len > sizeof(scmd->buffer)) 298 return -EINVAL; 299 300 memset(scmd, 0, sizeof(*scmd)); 301 cmd->cmd = command; 302 cmd->data_len = data_len; 303 cmd->data_buf = scmd->buffer; 304 cmd->reply_len = sizeof(scmd->buffer); 305 cmd->reply_buf = scmd->buffer; 306 cmd->done = done; 307 cmd->misc = misc; 308 309 va_start(list, misc); 310 for (i = 0; i < data_len; ++i) 311 scmd->buffer[i] = (u8)va_arg(list, int); 312 va_end(list); 313 314 return smu_queue_cmd(cmd); 315 } 316 EXPORT_SYMBOL(smu_queue_simple); 317 318 319 void smu_poll(void) 320 { 321 u8 gpio; 322 323 if (smu == NULL) 324 return; 325 326 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 327 if ((gpio & 7) == 7) 328 smu_db_intr(smu->db_irq, smu); 329 } 330 EXPORT_SYMBOL(smu_poll); 331 332 333 void smu_done_complete(struct smu_cmd *cmd, void *misc) 334 { 335 struct completion *comp = misc; 336 337 complete(comp); 338 } 339 EXPORT_SYMBOL(smu_done_complete); 340 341 342 void smu_spinwait_cmd(struct smu_cmd *cmd) 343 { 344 while(cmd->status == 1) 345 smu_poll(); 346 } 347 EXPORT_SYMBOL(smu_spinwait_cmd); 348 349 350 /* RTC low level commands */ 351 static inline int bcd2hex (int n) 352 { 353 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 354 } 355 356 357 static inline int hex2bcd (int n) 358 { 359 return ((n / 10) << 4) + (n % 10); 360 } 361 362 363 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 364 struct rtc_time *time) 365 { 366 cmd_buf->cmd = 0x8e; 367 cmd_buf->length = 8; 368 cmd_buf->data[0] = 0x80; 369 cmd_buf->data[1] = hex2bcd(time->tm_sec); 370 cmd_buf->data[2] = hex2bcd(time->tm_min); 371 cmd_buf->data[3] = hex2bcd(time->tm_hour); 372 cmd_buf->data[4] = time->tm_wday; 373 cmd_buf->data[5] = hex2bcd(time->tm_mday); 374 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 375 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 376 } 377 378 379 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 380 { 381 struct smu_simple_cmd cmd; 382 int rc; 383 384 if (smu == NULL) 385 return -ENODEV; 386 387 memset(time, 0, sizeof(struct rtc_time)); 388 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 389 SMU_CMD_RTC_GET_DATETIME); 390 if (rc) 391 return rc; 392 smu_spinwait_simple(&cmd); 393 394 time->tm_sec = bcd2hex(cmd.buffer[0]); 395 time->tm_min = bcd2hex(cmd.buffer[1]); 396 time->tm_hour = bcd2hex(cmd.buffer[2]); 397 time->tm_wday = bcd2hex(cmd.buffer[3]); 398 time->tm_mday = bcd2hex(cmd.buffer[4]); 399 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 400 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 401 402 return 0; 403 } 404 405 406 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 407 { 408 struct smu_simple_cmd cmd; 409 int rc; 410 411 if (smu == NULL) 412 return -ENODEV; 413 414 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 415 SMU_CMD_RTC_SET_DATETIME, 416 hex2bcd(time->tm_sec), 417 hex2bcd(time->tm_min), 418 hex2bcd(time->tm_hour), 419 time->tm_wday, 420 hex2bcd(time->tm_mday), 421 hex2bcd(time->tm_mon) + 1, 422 hex2bcd(time->tm_year - 100)); 423 if (rc) 424 return rc; 425 smu_spinwait_simple(&cmd); 426 427 return 0; 428 } 429 430 431 void smu_shutdown(void) 432 { 433 struct smu_simple_cmd cmd; 434 435 if (smu == NULL) 436 return; 437 438 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 439 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 440 return; 441 smu_spinwait_simple(&cmd); 442 for (;;) 443 ; 444 } 445 446 447 void smu_restart(void) 448 { 449 struct smu_simple_cmd cmd; 450 451 if (smu == NULL) 452 return; 453 454 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 455 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 456 return; 457 smu_spinwait_simple(&cmd); 458 for (;;) 459 ; 460 } 461 462 463 int smu_present(void) 464 { 465 return smu != NULL; 466 } 467 EXPORT_SYMBOL(smu_present); 468 469 470 int __init smu_init (void) 471 { 472 struct device_node *np; 473 const u32 *data; 474 int ret = 0; 475 476 np = of_find_node_by_type(NULL, "smu"); 477 if (np == NULL) 478 return -ENODEV; 479 480 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR); 481 482 if (smu_cmdbuf_abs == 0) { 483 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 484 ret = -EINVAL; 485 goto fail_np; 486 } 487 488 smu = alloc_bootmem(sizeof(struct smu_device)); 489 490 spin_lock_init(&smu->lock); 491 INIT_LIST_HEAD(&smu->cmd_list); 492 INIT_LIST_HEAD(&smu->cmd_i2c_list); 493 smu->of_node = np; 494 smu->db_irq = NO_IRQ; 495 smu->msg_irq = NO_IRQ; 496 497 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 498 * 32 bits value safely 499 */ 500 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 501 smu->cmd_buf = __va(smu_cmdbuf_abs); 502 503 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell"); 504 if (smu->db_node == NULL) { 505 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 506 ret = -ENXIO; 507 goto fail_bootmem; 508 } 509 data = of_get_property(smu->db_node, "reg", NULL); 510 if (data == NULL) { 511 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 512 ret = -ENXIO; 513 goto fail_db_node; 514 } 515 516 /* Current setup has one doorbell GPIO that does both doorbell 517 * and ack. GPIOs are at 0x50, best would be to find that out 518 * in the device-tree though. 519 */ 520 smu->doorbell = *data; 521 if (smu->doorbell < 0x50) 522 smu->doorbell += 0x50; 523 524 /* Now look for the smu-interrupt GPIO */ 525 do { 526 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt"); 527 if (smu->msg_node == NULL) 528 break; 529 data = of_get_property(smu->msg_node, "reg", NULL); 530 if (data == NULL) { 531 of_node_put(smu->msg_node); 532 smu->msg_node = NULL; 533 break; 534 } 535 smu->msg = *data; 536 if (smu->msg < 0x50) 537 smu->msg += 0x50; 538 } while(0); 539 540 /* Doorbell buffer is currently hard-coded, I didn't find a proper 541 * device-tree entry giving the address. Best would probably to use 542 * an offset for K2 base though, but let's do it that way for now. 543 */ 544 smu->db_buf = ioremap(0x8000860c, 0x1000); 545 if (smu->db_buf == NULL) { 546 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 547 ret = -ENXIO; 548 goto fail_msg_node; 549 } 550 551 /* U3 has an issue with NAP mode when issuing SMU commands */ 552 smu->broken_nap = pmac_get_uninorth_variant() < 4; 553 if (smu->broken_nap) 554 printk(KERN_INFO "SMU: using NAP mode workaround\n"); 555 556 sys_ctrler = SYS_CTRLER_SMU; 557 return 0; 558 559 fail_msg_node: 560 if (smu->msg_node) 561 of_node_put(smu->msg_node); 562 fail_db_node: 563 of_node_put(smu->db_node); 564 fail_bootmem: 565 free_bootmem(__pa(smu), sizeof(struct smu_device)); 566 smu = NULL; 567 fail_np: 568 of_node_put(np); 569 return ret; 570 } 571 572 573 static int smu_late_init(void) 574 { 575 if (!smu) 576 return 0; 577 578 init_timer(&smu->i2c_timer); 579 smu->i2c_timer.function = smu_i2c_retry; 580 smu->i2c_timer.data = (unsigned long)smu; 581 582 if (smu->db_node) { 583 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); 584 if (smu->db_irq == NO_IRQ) 585 printk(KERN_ERR "smu: failed to map irq for node %s\n", 586 smu->db_node->full_name); 587 } 588 if (smu->msg_node) { 589 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); 590 if (smu->msg_irq == NO_IRQ) 591 printk(KERN_ERR "smu: failed to map irq for node %s\n", 592 smu->msg_node->full_name); 593 } 594 595 /* 596 * Try to request the interrupts 597 */ 598 599 if (smu->db_irq != NO_IRQ) { 600 if (request_irq(smu->db_irq, smu_db_intr, 601 IRQF_SHARED, "SMU doorbell", smu) < 0) { 602 printk(KERN_WARNING "SMU: can't " 603 "request interrupt %d\n", 604 smu->db_irq); 605 smu->db_irq = NO_IRQ; 606 } 607 } 608 609 if (smu->msg_irq != NO_IRQ) { 610 if (request_irq(smu->msg_irq, smu_msg_intr, 611 IRQF_SHARED, "SMU message", smu) < 0) { 612 printk(KERN_WARNING "SMU: can't " 613 "request interrupt %d\n", 614 smu->msg_irq); 615 smu->msg_irq = NO_IRQ; 616 } 617 } 618 619 smu_irq_inited = 1; 620 return 0; 621 } 622 /* This has to be before arch_initcall as the low i2c stuff relies on the 623 * above having been done before we reach arch_initcalls 624 */ 625 core_initcall(smu_late_init); 626 627 /* 628 * sysfs visibility 629 */ 630 631 static void smu_expose_childs(struct work_struct *unused) 632 { 633 struct device_node *np; 634 635 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 636 if (of_device_is_compatible(np, "smu-sensors")) 637 of_platform_device_create(np, "smu-sensors", 638 &smu->of_dev->dev); 639 } 640 641 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 642 643 static int smu_platform_probe(struct platform_device* dev) 644 { 645 if (!smu) 646 return -ENODEV; 647 smu->of_dev = dev; 648 649 /* 650 * Ok, we are matched, now expose all i2c busses. We have to defer 651 * that unfortunately or it would deadlock inside the device model 652 */ 653 schedule_work(&smu_expose_childs_work); 654 655 return 0; 656 } 657 658 static const struct of_device_id smu_platform_match[] = 659 { 660 { 661 .type = "smu", 662 }, 663 {}, 664 }; 665 666 static struct platform_driver smu_of_platform_driver = 667 { 668 .driver = { 669 .name = "smu", 670 .of_match_table = smu_platform_match, 671 }, 672 .probe = smu_platform_probe, 673 }; 674 675 static int __init smu_init_sysfs(void) 676 { 677 /* 678 * For now, we don't power manage machines with an SMU chip, 679 * I'm a bit too far from figuring out how that works with those 680 * new chipsets, but that will come back and bite us 681 */ 682 platform_driver_register(&smu_of_platform_driver); 683 return 0; 684 } 685 686 device_initcall(smu_init_sysfs); 687 688 struct platform_device *smu_get_ofdev(void) 689 { 690 if (!smu) 691 return NULL; 692 return smu->of_dev; 693 } 694 695 EXPORT_SYMBOL_GPL(smu_get_ofdev); 696 697 /* 698 * i2c interface 699 */ 700 701 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 702 { 703 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 704 void *misc = cmd->misc; 705 unsigned long flags; 706 707 /* Check for read case */ 708 if (!fail && cmd->read) { 709 if (cmd->pdata[0] < 1) 710 fail = 1; 711 else 712 memcpy(cmd->info.data, &cmd->pdata[1], 713 cmd->info.datalen); 714 } 715 716 DPRINTK("SMU: completing, success: %d\n", !fail); 717 718 /* Update status and mark no pending i2c command with lock 719 * held so nobody comes in while we dequeue an eventual 720 * pending next i2c command 721 */ 722 spin_lock_irqsave(&smu->lock, flags); 723 smu->cmd_i2c_cur = NULL; 724 wmb(); 725 cmd->status = fail ? -EIO : 0; 726 727 /* Is there another i2c command waiting ? */ 728 if (!list_empty(&smu->cmd_i2c_list)) { 729 struct smu_i2c_cmd *newcmd; 730 731 /* Fetch it, new current, remove from list */ 732 newcmd = list_entry(smu->cmd_i2c_list.next, 733 struct smu_i2c_cmd, link); 734 smu->cmd_i2c_cur = newcmd; 735 list_del(&cmd->link); 736 737 /* Queue with low level smu */ 738 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 739 if (smu->cmd_cur == NULL) 740 smu_start_cmd(); 741 } 742 spin_unlock_irqrestore(&smu->lock, flags); 743 744 /* Call command completion handler if any */ 745 if (done) 746 done(cmd, misc); 747 748 } 749 750 751 static void smu_i2c_retry(unsigned long data) 752 { 753 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 754 755 DPRINTK("SMU: i2c failure, requeuing...\n"); 756 757 /* requeue command simply by resetting reply_len */ 758 cmd->pdata[0] = 0xff; 759 cmd->scmd.reply_len = sizeof(cmd->pdata); 760 smu_queue_cmd(&cmd->scmd); 761 } 762 763 764 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 765 { 766 struct smu_i2c_cmd *cmd = misc; 767 int fail = 0; 768 769 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 770 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 771 772 /* Check for possible status */ 773 if (scmd->status < 0) 774 fail = 1; 775 else if (cmd->read) { 776 if (cmd->stage == 0) 777 fail = cmd->pdata[0] != 0; 778 else 779 fail = cmd->pdata[0] >= 0x80; 780 } else { 781 fail = cmd->pdata[0] != 0; 782 } 783 784 /* Handle failures by requeuing command, after 5ms interval 785 */ 786 if (fail && --cmd->retries > 0) { 787 DPRINTK("SMU: i2c failure, starting timer...\n"); 788 BUG_ON(cmd != smu->cmd_i2c_cur); 789 if (!smu_irq_inited) { 790 mdelay(5); 791 smu_i2c_retry(0); 792 return; 793 } 794 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 795 return; 796 } 797 798 /* If failure or stage 1, command is complete */ 799 if (fail || cmd->stage != 0) { 800 smu_i2c_complete_command(cmd, fail); 801 return; 802 } 803 804 DPRINTK("SMU: going to stage 1\n"); 805 806 /* Ok, initial command complete, now poll status */ 807 scmd->reply_buf = cmd->pdata; 808 scmd->reply_len = sizeof(cmd->pdata); 809 scmd->data_buf = cmd->pdata; 810 scmd->data_len = 1; 811 cmd->pdata[0] = 0; 812 cmd->stage = 1; 813 cmd->retries = 20; 814 smu_queue_cmd(scmd); 815 } 816 817 818 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 819 { 820 unsigned long flags; 821 822 if (smu == NULL) 823 return -ENODEV; 824 825 /* Fill most fields of scmd */ 826 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 827 cmd->scmd.done = smu_i2c_low_completion; 828 cmd->scmd.misc = cmd; 829 cmd->scmd.reply_buf = cmd->pdata; 830 cmd->scmd.reply_len = sizeof(cmd->pdata); 831 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 832 cmd->scmd.status = 1; 833 cmd->stage = 0; 834 cmd->pdata[0] = 0xff; 835 cmd->retries = 20; 836 cmd->status = 1; 837 838 /* Check transfer type, sanitize some "info" fields 839 * based on transfer type and do more checking 840 */ 841 cmd->info.caddr = cmd->info.devaddr; 842 cmd->read = cmd->info.devaddr & 0x01; 843 switch(cmd->info.type) { 844 case SMU_I2C_TRANSFER_SIMPLE: 845 memset(&cmd->info.sublen, 0, 4); 846 break; 847 case SMU_I2C_TRANSFER_COMBINED: 848 cmd->info.devaddr &= 0xfe; 849 case SMU_I2C_TRANSFER_STDSUB: 850 if (cmd->info.sublen > 3) 851 return -EINVAL; 852 break; 853 default: 854 return -EINVAL; 855 } 856 857 /* Finish setting up command based on transfer direction 858 */ 859 if (cmd->read) { 860 if (cmd->info.datalen > SMU_I2C_READ_MAX) 861 return -EINVAL; 862 memset(cmd->info.data, 0xff, cmd->info.datalen); 863 cmd->scmd.data_len = 9; 864 } else { 865 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 866 return -EINVAL; 867 cmd->scmd.data_len = 9 + cmd->info.datalen; 868 } 869 870 DPRINTK("SMU: i2c enqueuing command\n"); 871 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 872 cmd->read ? "read" : "write", cmd->info.datalen, 873 cmd->info.bus, cmd->info.caddr, 874 cmd->info.subaddr[0], cmd->info.type); 875 876 877 /* Enqueue command in i2c list, and if empty, enqueue also in 878 * main command list 879 */ 880 spin_lock_irqsave(&smu->lock, flags); 881 if (smu->cmd_i2c_cur == NULL) { 882 smu->cmd_i2c_cur = cmd; 883 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 884 if (smu->cmd_cur == NULL) 885 smu_start_cmd(); 886 } else 887 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 888 spin_unlock_irqrestore(&smu->lock, flags); 889 890 return 0; 891 } 892 893 /* 894 * Handling of "partitions" 895 */ 896 897 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 898 { 899 DECLARE_COMPLETION_ONSTACK(comp); 900 unsigned int chunk; 901 struct smu_cmd cmd; 902 int rc; 903 u8 params[8]; 904 905 /* We currently use a chunk size of 0xe. We could check the 906 * SMU firmware version and use bigger sizes though 907 */ 908 chunk = 0xe; 909 910 while (len) { 911 unsigned int clen = min(len, chunk); 912 913 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 914 cmd.data_len = 7; 915 cmd.data_buf = params; 916 cmd.reply_len = chunk; 917 cmd.reply_buf = dest; 918 cmd.done = smu_done_complete; 919 cmd.misc = ∁ 920 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 921 params[1] = 0x4; 922 *((u32 *)¶ms[2]) = addr; 923 params[6] = clen; 924 925 rc = smu_queue_cmd(&cmd); 926 if (rc) 927 return rc; 928 wait_for_completion(&comp); 929 if (cmd.status != 0) 930 return rc; 931 if (cmd.reply_len != clen) { 932 printk(KERN_DEBUG "SMU: short read in " 933 "smu_read_datablock, got: %d, want: %d\n", 934 cmd.reply_len, clen); 935 return -EIO; 936 } 937 len -= clen; 938 addr += clen; 939 dest += clen; 940 } 941 return 0; 942 } 943 944 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 945 { 946 DECLARE_COMPLETION_ONSTACK(comp); 947 struct smu_simple_cmd cmd; 948 unsigned int addr, len, tlen; 949 struct smu_sdbp_header *hdr; 950 struct property *prop; 951 952 /* First query the partition info */ 953 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 954 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 955 smu_done_complete, &comp, 956 SMU_CMD_PARTITION_LATEST, id); 957 wait_for_completion(&comp); 958 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 959 cmd.cmd.status, cmd.cmd.reply_len); 960 961 /* Partition doesn't exist (or other error) */ 962 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 963 return NULL; 964 965 /* Fetch address and length from reply */ 966 addr = *((u16 *)cmd.buffer); 967 len = cmd.buffer[3] << 2; 968 /* Calucluate total length to allocate, including the 17 bytes 969 * for "sdb-partition-XX" that we append at the end of the buffer 970 */ 971 tlen = sizeof(struct property) + len + 18; 972 973 prop = kzalloc(tlen, GFP_KERNEL); 974 if (prop == NULL) 975 return NULL; 976 hdr = (struct smu_sdbp_header *)(prop + 1); 977 prop->name = ((char *)prop) + tlen - 18; 978 sprintf(prop->name, "sdb-partition-%02x", id); 979 prop->length = len; 980 prop->value = hdr; 981 prop->next = NULL; 982 983 /* Read the datablock */ 984 if (smu_read_datablock((u8 *)hdr, addr, len)) { 985 printk(KERN_DEBUG "SMU: datablock read failed while reading " 986 "partition %02x !\n", id); 987 goto failure; 988 } 989 990 /* Got it, check a few things and create the property */ 991 if (hdr->id != id) { 992 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 993 "%02x !\n", id, hdr->id); 994 goto failure; 995 } 996 if (of_add_property(smu->of_node, prop)) { 997 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 998 "property !\n", id); 999 goto failure; 1000 } 1001 1002 return hdr; 1003 failure: 1004 kfree(prop); 1005 return NULL; 1006 } 1007 1008 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 1009 * when interruptible is 1 1010 */ 1011 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 1012 unsigned int *size, int interruptible) 1013 { 1014 char pname[32]; 1015 const struct smu_sdbp_header *part; 1016 1017 if (!smu) 1018 return NULL; 1019 1020 sprintf(pname, "sdb-partition-%02x", id); 1021 1022 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 1023 1024 if (interruptible) { 1025 int rc; 1026 rc = mutex_lock_interruptible(&smu_part_access); 1027 if (rc) 1028 return ERR_PTR(rc); 1029 } else 1030 mutex_lock(&smu_part_access); 1031 1032 part = of_get_property(smu->of_node, pname, size); 1033 if (part == NULL) { 1034 DPRINTK("trying to extract from SMU ...\n"); 1035 part = smu_create_sdb_partition(id); 1036 if (part != NULL && size) 1037 *size = part->len << 2; 1038 } 1039 mutex_unlock(&smu_part_access); 1040 return part; 1041 } 1042 1043 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1044 { 1045 return __smu_get_sdb_partition(id, size, 0); 1046 } 1047 EXPORT_SYMBOL(smu_get_sdb_partition); 1048 1049 1050 /* 1051 * Userland driver interface 1052 */ 1053 1054 1055 static LIST_HEAD(smu_clist); 1056 static DEFINE_SPINLOCK(smu_clist_lock); 1057 1058 enum smu_file_mode { 1059 smu_file_commands, 1060 smu_file_events, 1061 smu_file_closing 1062 }; 1063 1064 struct smu_private 1065 { 1066 struct list_head list; 1067 enum smu_file_mode mode; 1068 int busy; 1069 struct smu_cmd cmd; 1070 spinlock_t lock; 1071 wait_queue_head_t wait; 1072 u8 buffer[SMU_MAX_DATA]; 1073 }; 1074 1075 1076 static int smu_open(struct inode *inode, struct file *file) 1077 { 1078 struct smu_private *pp; 1079 unsigned long flags; 1080 1081 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1082 if (pp == 0) 1083 return -ENOMEM; 1084 spin_lock_init(&pp->lock); 1085 pp->mode = smu_file_commands; 1086 init_waitqueue_head(&pp->wait); 1087 1088 mutex_lock(&smu_mutex); 1089 spin_lock_irqsave(&smu_clist_lock, flags); 1090 list_add(&pp->list, &smu_clist); 1091 spin_unlock_irqrestore(&smu_clist_lock, flags); 1092 file->private_data = pp; 1093 mutex_unlock(&smu_mutex); 1094 1095 return 0; 1096 } 1097 1098 1099 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1100 { 1101 struct smu_private *pp = misc; 1102 1103 wake_up_all(&pp->wait); 1104 } 1105 1106 1107 static ssize_t smu_write(struct file *file, const char __user *buf, 1108 size_t count, loff_t *ppos) 1109 { 1110 struct smu_private *pp = file->private_data; 1111 unsigned long flags; 1112 struct smu_user_cmd_hdr hdr; 1113 int rc = 0; 1114 1115 if (pp->busy) 1116 return -EBUSY; 1117 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1118 return -EFAULT; 1119 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1120 pp->mode = smu_file_events; 1121 return 0; 1122 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1123 const struct smu_sdbp_header *part; 1124 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1125 if (part == NULL) 1126 return -EINVAL; 1127 else if (IS_ERR(part)) 1128 return PTR_ERR(part); 1129 return 0; 1130 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1131 return -EINVAL; 1132 else if (pp->mode != smu_file_commands) 1133 return -EBADFD; 1134 else if (hdr.data_len > SMU_MAX_DATA) 1135 return -EINVAL; 1136 1137 spin_lock_irqsave(&pp->lock, flags); 1138 if (pp->busy) { 1139 spin_unlock_irqrestore(&pp->lock, flags); 1140 return -EBUSY; 1141 } 1142 pp->busy = 1; 1143 pp->cmd.status = 1; 1144 spin_unlock_irqrestore(&pp->lock, flags); 1145 1146 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1147 pp->busy = 0; 1148 return -EFAULT; 1149 } 1150 1151 pp->cmd.cmd = hdr.cmd; 1152 pp->cmd.data_len = hdr.data_len; 1153 pp->cmd.reply_len = SMU_MAX_DATA; 1154 pp->cmd.data_buf = pp->buffer; 1155 pp->cmd.reply_buf = pp->buffer; 1156 pp->cmd.done = smu_user_cmd_done; 1157 pp->cmd.misc = pp; 1158 rc = smu_queue_cmd(&pp->cmd); 1159 if (rc < 0) 1160 return rc; 1161 return count; 1162 } 1163 1164 1165 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1166 char __user *buf, size_t count) 1167 { 1168 DECLARE_WAITQUEUE(wait, current); 1169 struct smu_user_reply_hdr hdr; 1170 unsigned long flags; 1171 int size, rc = 0; 1172 1173 if (!pp->busy) 1174 return 0; 1175 if (count < sizeof(struct smu_user_reply_hdr)) 1176 return -EOVERFLOW; 1177 spin_lock_irqsave(&pp->lock, flags); 1178 if (pp->cmd.status == 1) { 1179 if (file->f_flags & O_NONBLOCK) { 1180 spin_unlock_irqrestore(&pp->lock, flags); 1181 return -EAGAIN; 1182 } 1183 add_wait_queue(&pp->wait, &wait); 1184 for (;;) { 1185 set_current_state(TASK_INTERRUPTIBLE); 1186 rc = 0; 1187 if (pp->cmd.status != 1) 1188 break; 1189 rc = -ERESTARTSYS; 1190 if (signal_pending(current)) 1191 break; 1192 spin_unlock_irqrestore(&pp->lock, flags); 1193 schedule(); 1194 spin_lock_irqsave(&pp->lock, flags); 1195 } 1196 set_current_state(TASK_RUNNING); 1197 remove_wait_queue(&pp->wait, &wait); 1198 } 1199 spin_unlock_irqrestore(&pp->lock, flags); 1200 if (rc) 1201 return rc; 1202 if (pp->cmd.status != 0) 1203 pp->cmd.reply_len = 0; 1204 size = sizeof(hdr) + pp->cmd.reply_len; 1205 if (count < size) 1206 size = count; 1207 rc = size; 1208 hdr.status = pp->cmd.status; 1209 hdr.reply_len = pp->cmd.reply_len; 1210 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1211 return -EFAULT; 1212 size -= sizeof(hdr); 1213 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1214 return -EFAULT; 1215 pp->busy = 0; 1216 1217 return rc; 1218 } 1219 1220 1221 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1222 char __user *buf, size_t count) 1223 { 1224 /* Not implemented */ 1225 msleep_interruptible(1000); 1226 return 0; 1227 } 1228 1229 1230 static ssize_t smu_read(struct file *file, char __user *buf, 1231 size_t count, loff_t *ppos) 1232 { 1233 struct smu_private *pp = file->private_data; 1234 1235 if (pp->mode == smu_file_commands) 1236 return smu_read_command(file, pp, buf, count); 1237 if (pp->mode == smu_file_events) 1238 return smu_read_events(file, pp, buf, count); 1239 1240 return -EBADFD; 1241 } 1242 1243 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1244 { 1245 struct smu_private *pp = file->private_data; 1246 unsigned int mask = 0; 1247 unsigned long flags; 1248 1249 if (pp == 0) 1250 return 0; 1251 1252 if (pp->mode == smu_file_commands) { 1253 poll_wait(file, &pp->wait, wait); 1254 1255 spin_lock_irqsave(&pp->lock, flags); 1256 if (pp->busy && pp->cmd.status != 1) 1257 mask |= POLLIN; 1258 spin_unlock_irqrestore(&pp->lock, flags); 1259 } 1260 if (pp->mode == smu_file_events) { 1261 /* Not yet implemented */ 1262 } 1263 return mask; 1264 } 1265 1266 static int smu_release(struct inode *inode, struct file *file) 1267 { 1268 struct smu_private *pp = file->private_data; 1269 unsigned long flags; 1270 unsigned int busy; 1271 1272 if (pp == 0) 1273 return 0; 1274 1275 file->private_data = NULL; 1276 1277 /* Mark file as closing to avoid races with new request */ 1278 spin_lock_irqsave(&pp->lock, flags); 1279 pp->mode = smu_file_closing; 1280 busy = pp->busy; 1281 1282 /* Wait for any pending request to complete */ 1283 if (busy && pp->cmd.status == 1) { 1284 DECLARE_WAITQUEUE(wait, current); 1285 1286 add_wait_queue(&pp->wait, &wait); 1287 for (;;) { 1288 set_current_state(TASK_UNINTERRUPTIBLE); 1289 if (pp->cmd.status != 1) 1290 break; 1291 spin_unlock_irqrestore(&pp->lock, flags); 1292 schedule(); 1293 spin_lock_irqsave(&pp->lock, flags); 1294 } 1295 set_current_state(TASK_RUNNING); 1296 remove_wait_queue(&pp->wait, &wait); 1297 } 1298 spin_unlock_irqrestore(&pp->lock, flags); 1299 1300 spin_lock_irqsave(&smu_clist_lock, flags); 1301 list_del(&pp->list); 1302 spin_unlock_irqrestore(&smu_clist_lock, flags); 1303 kfree(pp); 1304 1305 return 0; 1306 } 1307 1308 1309 static const struct file_operations smu_device_fops = { 1310 .llseek = no_llseek, 1311 .read = smu_read, 1312 .write = smu_write, 1313 .poll = smu_fpoll, 1314 .open = smu_open, 1315 .release = smu_release, 1316 }; 1317 1318 static struct miscdevice pmu_device = { 1319 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1320 }; 1321 1322 static int smu_device_init(void) 1323 { 1324 if (!smu) 1325 return -ENODEV; 1326 if (misc_register(&pmu_device) < 0) 1327 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1328 return 0; 1329 } 1330 device_initcall(smu_device_init); 1331