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 #include <linux/of_device.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/abs_addr.h> 50 #include <asm/uaccess.h> 51 52 #define VERSION "0.7" 53 #define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp." 54 55 #undef DEBUG_SMU 56 57 #ifdef DEBUG_SMU 58 #define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0) 59 #else 60 #define DPRINTK(fmt, args...) do { } while (0) 61 #endif 62 63 /* 64 * This is the command buffer passed to the SMU hardware 65 */ 66 #define SMU_MAX_DATA 254 67 68 struct smu_cmd_buf { 69 u8 cmd; 70 u8 length; 71 u8 data[SMU_MAX_DATA]; 72 }; 73 74 struct smu_device { 75 spinlock_t lock; 76 struct device_node *of_node; 77 struct platform_device *of_dev; 78 int doorbell; /* doorbell gpio */ 79 u32 __iomem *db_buf; /* doorbell buffer */ 80 struct device_node *db_node; 81 unsigned int db_irq; 82 int msg; 83 struct device_node *msg_node; 84 unsigned int msg_irq; 85 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ 86 u32 cmd_buf_abs; /* command buffer absolute */ 87 struct list_head cmd_list; 88 struct smu_cmd *cmd_cur; /* pending command */ 89 int broken_nap; 90 struct list_head cmd_i2c_list; 91 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 92 struct timer_list i2c_timer; 93 }; 94 95 /* 96 * I don't think there will ever be more than one SMU, so 97 * for now, just hard code that 98 */ 99 static DEFINE_MUTEX(smu_mutex); 100 static struct smu_device *smu; 101 static DEFINE_MUTEX(smu_part_access); 102 static int smu_irq_inited; 103 104 static void smu_i2c_retry(unsigned long data); 105 106 /* 107 * SMU driver low level stuff 108 */ 109 110 static void smu_start_cmd(void) 111 { 112 unsigned long faddr, fend; 113 struct smu_cmd *cmd; 114 115 if (list_empty(&smu->cmd_list)) 116 return; 117 118 /* Fetch first command in queue */ 119 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 120 smu->cmd_cur = cmd; 121 list_del(&cmd->link); 122 123 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 124 cmd->data_len); 125 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 126 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 127 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 128 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 129 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 130 131 /* Fill the SMU command buffer */ 132 smu->cmd_buf->cmd = cmd->cmd; 133 smu->cmd_buf->length = cmd->data_len; 134 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 135 136 /* Flush command and data to RAM */ 137 faddr = (unsigned long)smu->cmd_buf; 138 fend = faddr + smu->cmd_buf->length + 2; 139 flush_inval_dcache_range(faddr, fend); 140 141 142 /* We also disable NAP mode for the duration of the command 143 * on U3 based machines. 144 * This is slightly racy as it can be written back to 1 by a sysctl 145 * but that never happens in practice. There seem to be an issue with 146 * U3 based machines such as the iMac G5 where napping for the 147 * whole duration of the command prevents the SMU from fetching it 148 * from memory. This might be related to the strange i2c based 149 * mechanism the SMU uses to access memory. 150 */ 151 if (smu->broken_nap) 152 powersave_nap = 0; 153 154 /* This isn't exactly a DMA mapping here, I suspect 155 * the SMU is actually communicating with us via i2c to the 156 * northbridge or the CPU to access RAM. 157 */ 158 writel(smu->cmd_buf_abs, smu->db_buf); 159 160 /* Ring the SMU doorbell */ 161 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 162 } 163 164 165 static irqreturn_t smu_db_intr(int irq, void *arg) 166 { 167 unsigned long flags; 168 struct smu_cmd *cmd; 169 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 170 void *misc = NULL; 171 u8 gpio; 172 int rc = 0; 173 174 /* SMU completed the command, well, we hope, let's make sure 175 * of it 176 */ 177 spin_lock_irqsave(&smu->lock, flags); 178 179 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 180 if ((gpio & 7) != 7) { 181 spin_unlock_irqrestore(&smu->lock, flags); 182 return IRQ_HANDLED; 183 } 184 185 cmd = smu->cmd_cur; 186 smu->cmd_cur = NULL; 187 if (cmd == NULL) 188 goto bail; 189 190 if (rc == 0) { 191 unsigned long faddr; 192 int reply_len; 193 u8 ack; 194 195 /* CPU might have brought back the cache line, so we need 196 * to flush again before peeking at the SMU response. We 197 * flush the entire buffer for now as we haven't read the 198 * reply length (it's only 2 cache lines anyway) 199 */ 200 faddr = (unsigned long)smu->cmd_buf; 201 flush_inval_dcache_range(faddr, faddr + 256); 202 203 /* Now check ack */ 204 ack = (~cmd->cmd) & 0xff; 205 if (ack != smu->cmd_buf->cmd) { 206 DPRINTK("SMU: incorrect ack, want %x got %x\n", 207 ack, smu->cmd_buf->cmd); 208 rc = -EIO; 209 } 210 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 211 DPRINTK("SMU: reply len: %d\n", reply_len); 212 if (reply_len > cmd->reply_len) { 213 printk(KERN_WARNING "SMU: reply buffer too small," 214 "got %d bytes for a %d bytes buffer\n", 215 reply_len, cmd->reply_len); 216 reply_len = cmd->reply_len; 217 } 218 cmd->reply_len = reply_len; 219 if (cmd->reply_buf && reply_len) 220 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 221 } 222 223 /* Now complete the command. Write status last in order as we lost 224 * ownership of the command structure as soon as it's no longer -1 225 */ 226 done = cmd->done; 227 misc = cmd->misc; 228 mb(); 229 cmd->status = rc; 230 231 /* Re-enable NAP mode */ 232 if (smu->broken_nap) 233 powersave_nap = 1; 234 bail: 235 /* Start next command if any */ 236 smu_start_cmd(); 237 spin_unlock_irqrestore(&smu->lock, flags); 238 239 /* Call command completion handler if any */ 240 if (done) 241 done(cmd, misc); 242 243 /* It's an edge interrupt, nothing to do */ 244 return IRQ_HANDLED; 245 } 246 247 248 static irqreturn_t smu_msg_intr(int irq, void *arg) 249 { 250 /* I don't quite know what to do with this one, we seem to never 251 * receive it, so I suspect we have to arm it someway in the SMU 252 * to start getting events that way. 253 */ 254 255 printk(KERN_INFO "SMU: message interrupt !\n"); 256 257 /* It's an edge interrupt, nothing to do */ 258 return IRQ_HANDLED; 259 } 260 261 262 /* 263 * Queued command management. 264 * 265 */ 266 267 int smu_queue_cmd(struct smu_cmd *cmd) 268 { 269 unsigned long flags; 270 271 if (smu == NULL) 272 return -ENODEV; 273 if (cmd->data_len > SMU_MAX_DATA || 274 cmd->reply_len > SMU_MAX_DATA) 275 return -EINVAL; 276 277 cmd->status = 1; 278 spin_lock_irqsave(&smu->lock, flags); 279 list_add_tail(&cmd->link, &smu->cmd_list); 280 if (smu->cmd_cur == NULL) 281 smu_start_cmd(); 282 spin_unlock_irqrestore(&smu->lock, flags); 283 284 /* Workaround for early calls when irq isn't available */ 285 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 286 smu_spinwait_cmd(cmd); 287 288 return 0; 289 } 290 EXPORT_SYMBOL(smu_queue_cmd); 291 292 293 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 294 unsigned int data_len, 295 void (*done)(struct smu_cmd *cmd, void *misc), 296 void *misc, ...) 297 { 298 struct smu_cmd *cmd = &scmd->cmd; 299 va_list list; 300 int i; 301 302 if (data_len > sizeof(scmd->buffer)) 303 return -EINVAL; 304 305 memset(scmd, 0, sizeof(*scmd)); 306 cmd->cmd = command; 307 cmd->data_len = data_len; 308 cmd->data_buf = scmd->buffer; 309 cmd->reply_len = sizeof(scmd->buffer); 310 cmd->reply_buf = scmd->buffer; 311 cmd->done = done; 312 cmd->misc = misc; 313 314 va_start(list, misc); 315 for (i = 0; i < data_len; ++i) 316 scmd->buffer[i] = (u8)va_arg(list, int); 317 va_end(list); 318 319 return smu_queue_cmd(cmd); 320 } 321 EXPORT_SYMBOL(smu_queue_simple); 322 323 324 void smu_poll(void) 325 { 326 u8 gpio; 327 328 if (smu == NULL) 329 return; 330 331 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 332 if ((gpio & 7) == 7) 333 smu_db_intr(smu->db_irq, smu); 334 } 335 EXPORT_SYMBOL(smu_poll); 336 337 338 void smu_done_complete(struct smu_cmd *cmd, void *misc) 339 { 340 struct completion *comp = misc; 341 342 complete(comp); 343 } 344 EXPORT_SYMBOL(smu_done_complete); 345 346 347 void smu_spinwait_cmd(struct smu_cmd *cmd) 348 { 349 while(cmd->status == 1) 350 smu_poll(); 351 } 352 EXPORT_SYMBOL(smu_spinwait_cmd); 353 354 355 /* RTC low level commands */ 356 static inline int bcd2hex (int n) 357 { 358 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 359 } 360 361 362 static inline int hex2bcd (int n) 363 { 364 return ((n / 10) << 4) + (n % 10); 365 } 366 367 368 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 369 struct rtc_time *time) 370 { 371 cmd_buf->cmd = 0x8e; 372 cmd_buf->length = 8; 373 cmd_buf->data[0] = 0x80; 374 cmd_buf->data[1] = hex2bcd(time->tm_sec); 375 cmd_buf->data[2] = hex2bcd(time->tm_min); 376 cmd_buf->data[3] = hex2bcd(time->tm_hour); 377 cmd_buf->data[4] = time->tm_wday; 378 cmd_buf->data[5] = hex2bcd(time->tm_mday); 379 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 380 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 381 } 382 383 384 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 385 { 386 struct smu_simple_cmd cmd; 387 int rc; 388 389 if (smu == NULL) 390 return -ENODEV; 391 392 memset(time, 0, sizeof(struct rtc_time)); 393 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 394 SMU_CMD_RTC_GET_DATETIME); 395 if (rc) 396 return rc; 397 smu_spinwait_simple(&cmd); 398 399 time->tm_sec = bcd2hex(cmd.buffer[0]); 400 time->tm_min = bcd2hex(cmd.buffer[1]); 401 time->tm_hour = bcd2hex(cmd.buffer[2]); 402 time->tm_wday = bcd2hex(cmd.buffer[3]); 403 time->tm_mday = bcd2hex(cmd.buffer[4]); 404 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 405 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 406 407 return 0; 408 } 409 410 411 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 412 { 413 struct smu_simple_cmd cmd; 414 int rc; 415 416 if (smu == NULL) 417 return -ENODEV; 418 419 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 420 SMU_CMD_RTC_SET_DATETIME, 421 hex2bcd(time->tm_sec), 422 hex2bcd(time->tm_min), 423 hex2bcd(time->tm_hour), 424 time->tm_wday, 425 hex2bcd(time->tm_mday), 426 hex2bcd(time->tm_mon) + 1, 427 hex2bcd(time->tm_year - 100)); 428 if (rc) 429 return rc; 430 smu_spinwait_simple(&cmd); 431 432 return 0; 433 } 434 435 436 void smu_shutdown(void) 437 { 438 struct smu_simple_cmd cmd; 439 440 if (smu == NULL) 441 return; 442 443 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 444 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 445 return; 446 smu_spinwait_simple(&cmd); 447 for (;;) 448 ; 449 } 450 451 452 void smu_restart(void) 453 { 454 struct smu_simple_cmd cmd; 455 456 if (smu == NULL) 457 return; 458 459 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 460 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 461 return; 462 smu_spinwait_simple(&cmd); 463 for (;;) 464 ; 465 } 466 467 468 int smu_present(void) 469 { 470 return smu != NULL; 471 } 472 EXPORT_SYMBOL(smu_present); 473 474 475 int __init smu_init (void) 476 { 477 struct device_node *np; 478 const u32 *data; 479 int ret = 0; 480 481 np = of_find_node_by_type(NULL, "smu"); 482 if (np == NULL) 483 return -ENODEV; 484 485 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR); 486 487 if (smu_cmdbuf_abs == 0) { 488 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 489 ret = -EINVAL; 490 goto fail_np; 491 } 492 493 smu = alloc_bootmem(sizeof(struct smu_device)); 494 495 spin_lock_init(&smu->lock); 496 INIT_LIST_HEAD(&smu->cmd_list); 497 INIT_LIST_HEAD(&smu->cmd_i2c_list); 498 smu->of_node = np; 499 smu->db_irq = NO_IRQ; 500 smu->msg_irq = NO_IRQ; 501 502 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 503 * 32 bits value safely 504 */ 505 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 506 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); 507 508 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell"); 509 if (smu->db_node == NULL) { 510 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 511 ret = -ENXIO; 512 goto fail_bootmem; 513 } 514 data = of_get_property(smu->db_node, "reg", NULL); 515 if (data == NULL) { 516 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 517 ret = -ENXIO; 518 goto fail_db_node; 519 } 520 521 /* Current setup has one doorbell GPIO that does both doorbell 522 * and ack. GPIOs are at 0x50, best would be to find that out 523 * in the device-tree though. 524 */ 525 smu->doorbell = *data; 526 if (smu->doorbell < 0x50) 527 smu->doorbell += 0x50; 528 529 /* Now look for the smu-interrupt GPIO */ 530 do { 531 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt"); 532 if (smu->msg_node == NULL) 533 break; 534 data = of_get_property(smu->msg_node, "reg", NULL); 535 if (data == NULL) { 536 of_node_put(smu->msg_node); 537 smu->msg_node = NULL; 538 break; 539 } 540 smu->msg = *data; 541 if (smu->msg < 0x50) 542 smu->msg += 0x50; 543 } while(0); 544 545 /* Doorbell buffer is currently hard-coded, I didn't find a proper 546 * device-tree entry giving the address. Best would probably to use 547 * an offset for K2 base though, but let's do it that way for now. 548 */ 549 smu->db_buf = ioremap(0x8000860c, 0x1000); 550 if (smu->db_buf == NULL) { 551 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 552 ret = -ENXIO; 553 goto fail_msg_node; 554 } 555 556 /* U3 has an issue with NAP mode when issuing SMU commands */ 557 smu->broken_nap = pmac_get_uninorth_variant() < 4; 558 if (smu->broken_nap) 559 printk(KERN_INFO "SMU: using NAP mode workaround\n"); 560 561 sys_ctrler = SYS_CTRLER_SMU; 562 return 0; 563 564 fail_msg_node: 565 if (smu->msg_node) 566 of_node_put(smu->msg_node); 567 fail_db_node: 568 of_node_put(smu->db_node); 569 fail_bootmem: 570 free_bootmem((unsigned long)smu, sizeof(struct smu_device)); 571 smu = NULL; 572 fail_np: 573 of_node_put(np); 574 return ret; 575 } 576 577 578 static int smu_late_init(void) 579 { 580 if (!smu) 581 return 0; 582 583 init_timer(&smu->i2c_timer); 584 smu->i2c_timer.function = smu_i2c_retry; 585 smu->i2c_timer.data = (unsigned long)smu; 586 587 if (smu->db_node) { 588 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); 589 if (smu->db_irq == NO_IRQ) 590 printk(KERN_ERR "smu: failed to map irq for node %s\n", 591 smu->db_node->full_name); 592 } 593 if (smu->msg_node) { 594 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); 595 if (smu->msg_irq == NO_IRQ) 596 printk(KERN_ERR "smu: failed to map irq for node %s\n", 597 smu->msg_node->full_name); 598 } 599 600 /* 601 * Try to request the interrupts 602 */ 603 604 if (smu->db_irq != NO_IRQ) { 605 if (request_irq(smu->db_irq, smu_db_intr, 606 IRQF_SHARED, "SMU doorbell", smu) < 0) { 607 printk(KERN_WARNING "SMU: can't " 608 "request interrupt %d\n", 609 smu->db_irq); 610 smu->db_irq = NO_IRQ; 611 } 612 } 613 614 if (smu->msg_irq != NO_IRQ) { 615 if (request_irq(smu->msg_irq, smu_msg_intr, 616 IRQF_SHARED, "SMU message", smu) < 0) { 617 printk(KERN_WARNING "SMU: can't " 618 "request interrupt %d\n", 619 smu->msg_irq); 620 smu->msg_irq = NO_IRQ; 621 } 622 } 623 624 smu_irq_inited = 1; 625 return 0; 626 } 627 /* This has to be before arch_initcall as the low i2c stuff relies on the 628 * above having been done before we reach arch_initcalls 629 */ 630 core_initcall(smu_late_init); 631 632 /* 633 * sysfs visibility 634 */ 635 636 static void smu_expose_childs(struct work_struct *unused) 637 { 638 struct device_node *np; 639 640 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 641 if (of_device_is_compatible(np, "smu-sensors")) 642 of_platform_device_create(np, "smu-sensors", 643 &smu->of_dev->dev); 644 } 645 646 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 647 648 static int smu_platform_probe(struct platform_device* dev, 649 const struct of_device_id *match) 650 { 651 if (!smu) 652 return -ENODEV; 653 smu->of_dev = dev; 654 655 /* 656 * Ok, we are matched, now expose all i2c busses. We have to defer 657 * that unfortunately or it would deadlock inside the device model 658 */ 659 schedule_work(&smu_expose_childs_work); 660 661 return 0; 662 } 663 664 static const struct of_device_id smu_platform_match[] = 665 { 666 { 667 .type = "smu", 668 }, 669 {}, 670 }; 671 672 static struct of_platform_driver smu_of_platform_driver = 673 { 674 .driver = { 675 .name = "smu", 676 .owner = THIS_MODULE, 677 .of_match_table = smu_platform_match, 678 }, 679 .probe = smu_platform_probe, 680 }; 681 682 static int __init smu_init_sysfs(void) 683 { 684 /* 685 * Due to sysfs bogosity, a sysdev is not a real device, so 686 * we should in fact create both if we want sysdev semantics 687 * for power management. 688 * For now, we don't power manage machines with an SMU chip, 689 * I'm a bit too far from figuring out how that works with those 690 * new chipsets, but that will come back and bite us 691 */ 692 of_register_platform_driver(&smu_of_platform_driver); 693 return 0; 694 } 695 696 device_initcall(smu_init_sysfs); 697 698 struct platform_device *smu_get_ofdev(void) 699 { 700 if (!smu) 701 return NULL; 702 return smu->of_dev; 703 } 704 705 EXPORT_SYMBOL_GPL(smu_get_ofdev); 706 707 /* 708 * i2c interface 709 */ 710 711 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 712 { 713 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 714 void *misc = cmd->misc; 715 unsigned long flags; 716 717 /* Check for read case */ 718 if (!fail && cmd->read) { 719 if (cmd->pdata[0] < 1) 720 fail = 1; 721 else 722 memcpy(cmd->info.data, &cmd->pdata[1], 723 cmd->info.datalen); 724 } 725 726 DPRINTK("SMU: completing, success: %d\n", !fail); 727 728 /* Update status and mark no pending i2c command with lock 729 * held so nobody comes in while we dequeue an eventual 730 * pending next i2c command 731 */ 732 spin_lock_irqsave(&smu->lock, flags); 733 smu->cmd_i2c_cur = NULL; 734 wmb(); 735 cmd->status = fail ? -EIO : 0; 736 737 /* Is there another i2c command waiting ? */ 738 if (!list_empty(&smu->cmd_i2c_list)) { 739 struct smu_i2c_cmd *newcmd; 740 741 /* Fetch it, new current, remove from list */ 742 newcmd = list_entry(smu->cmd_i2c_list.next, 743 struct smu_i2c_cmd, link); 744 smu->cmd_i2c_cur = newcmd; 745 list_del(&cmd->link); 746 747 /* Queue with low level smu */ 748 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 749 if (smu->cmd_cur == NULL) 750 smu_start_cmd(); 751 } 752 spin_unlock_irqrestore(&smu->lock, flags); 753 754 /* Call command completion handler if any */ 755 if (done) 756 done(cmd, misc); 757 758 } 759 760 761 static void smu_i2c_retry(unsigned long data) 762 { 763 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 764 765 DPRINTK("SMU: i2c failure, requeuing...\n"); 766 767 /* requeue command simply by resetting reply_len */ 768 cmd->pdata[0] = 0xff; 769 cmd->scmd.reply_len = sizeof(cmd->pdata); 770 smu_queue_cmd(&cmd->scmd); 771 } 772 773 774 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 775 { 776 struct smu_i2c_cmd *cmd = misc; 777 int fail = 0; 778 779 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 780 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 781 782 /* Check for possible status */ 783 if (scmd->status < 0) 784 fail = 1; 785 else if (cmd->read) { 786 if (cmd->stage == 0) 787 fail = cmd->pdata[0] != 0; 788 else 789 fail = cmd->pdata[0] >= 0x80; 790 } else { 791 fail = cmd->pdata[0] != 0; 792 } 793 794 /* Handle failures by requeuing command, after 5ms interval 795 */ 796 if (fail && --cmd->retries > 0) { 797 DPRINTK("SMU: i2c failure, starting timer...\n"); 798 BUG_ON(cmd != smu->cmd_i2c_cur); 799 if (!smu_irq_inited) { 800 mdelay(5); 801 smu_i2c_retry(0); 802 return; 803 } 804 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 805 return; 806 } 807 808 /* If failure or stage 1, command is complete */ 809 if (fail || cmd->stage != 0) { 810 smu_i2c_complete_command(cmd, fail); 811 return; 812 } 813 814 DPRINTK("SMU: going to stage 1\n"); 815 816 /* Ok, initial command complete, now poll status */ 817 scmd->reply_buf = cmd->pdata; 818 scmd->reply_len = sizeof(cmd->pdata); 819 scmd->data_buf = cmd->pdata; 820 scmd->data_len = 1; 821 cmd->pdata[0] = 0; 822 cmd->stage = 1; 823 cmd->retries = 20; 824 smu_queue_cmd(scmd); 825 } 826 827 828 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 829 { 830 unsigned long flags; 831 832 if (smu == NULL) 833 return -ENODEV; 834 835 /* Fill most fields of scmd */ 836 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 837 cmd->scmd.done = smu_i2c_low_completion; 838 cmd->scmd.misc = cmd; 839 cmd->scmd.reply_buf = cmd->pdata; 840 cmd->scmd.reply_len = sizeof(cmd->pdata); 841 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 842 cmd->scmd.status = 1; 843 cmd->stage = 0; 844 cmd->pdata[0] = 0xff; 845 cmd->retries = 20; 846 cmd->status = 1; 847 848 /* Check transfer type, sanitize some "info" fields 849 * based on transfer type and do more checking 850 */ 851 cmd->info.caddr = cmd->info.devaddr; 852 cmd->read = cmd->info.devaddr & 0x01; 853 switch(cmd->info.type) { 854 case SMU_I2C_TRANSFER_SIMPLE: 855 memset(&cmd->info.sublen, 0, 4); 856 break; 857 case SMU_I2C_TRANSFER_COMBINED: 858 cmd->info.devaddr &= 0xfe; 859 case SMU_I2C_TRANSFER_STDSUB: 860 if (cmd->info.sublen > 3) 861 return -EINVAL; 862 break; 863 default: 864 return -EINVAL; 865 } 866 867 /* Finish setting up command based on transfer direction 868 */ 869 if (cmd->read) { 870 if (cmd->info.datalen > SMU_I2C_READ_MAX) 871 return -EINVAL; 872 memset(cmd->info.data, 0xff, cmd->info.datalen); 873 cmd->scmd.data_len = 9; 874 } else { 875 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 876 return -EINVAL; 877 cmd->scmd.data_len = 9 + cmd->info.datalen; 878 } 879 880 DPRINTK("SMU: i2c enqueuing command\n"); 881 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 882 cmd->read ? "read" : "write", cmd->info.datalen, 883 cmd->info.bus, cmd->info.caddr, 884 cmd->info.subaddr[0], cmd->info.type); 885 886 887 /* Enqueue command in i2c list, and if empty, enqueue also in 888 * main command list 889 */ 890 spin_lock_irqsave(&smu->lock, flags); 891 if (smu->cmd_i2c_cur == NULL) { 892 smu->cmd_i2c_cur = cmd; 893 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 894 if (smu->cmd_cur == NULL) 895 smu_start_cmd(); 896 } else 897 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 898 spin_unlock_irqrestore(&smu->lock, flags); 899 900 return 0; 901 } 902 903 /* 904 * Handling of "partitions" 905 */ 906 907 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 908 { 909 DECLARE_COMPLETION_ONSTACK(comp); 910 unsigned int chunk; 911 struct smu_cmd cmd; 912 int rc; 913 u8 params[8]; 914 915 /* We currently use a chunk size of 0xe. We could check the 916 * SMU firmware version and use bigger sizes though 917 */ 918 chunk = 0xe; 919 920 while (len) { 921 unsigned int clen = min(len, chunk); 922 923 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 924 cmd.data_len = 7; 925 cmd.data_buf = params; 926 cmd.reply_len = chunk; 927 cmd.reply_buf = dest; 928 cmd.done = smu_done_complete; 929 cmd.misc = ∁ 930 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 931 params[1] = 0x4; 932 *((u32 *)¶ms[2]) = addr; 933 params[6] = clen; 934 935 rc = smu_queue_cmd(&cmd); 936 if (rc) 937 return rc; 938 wait_for_completion(&comp); 939 if (cmd.status != 0) 940 return rc; 941 if (cmd.reply_len != clen) { 942 printk(KERN_DEBUG "SMU: short read in " 943 "smu_read_datablock, got: %d, want: %d\n", 944 cmd.reply_len, clen); 945 return -EIO; 946 } 947 len -= clen; 948 addr += clen; 949 dest += clen; 950 } 951 return 0; 952 } 953 954 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 955 { 956 DECLARE_COMPLETION_ONSTACK(comp); 957 struct smu_simple_cmd cmd; 958 unsigned int addr, len, tlen; 959 struct smu_sdbp_header *hdr; 960 struct property *prop; 961 962 /* First query the partition info */ 963 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 964 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 965 smu_done_complete, &comp, 966 SMU_CMD_PARTITION_LATEST, id); 967 wait_for_completion(&comp); 968 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 969 cmd.cmd.status, cmd.cmd.reply_len); 970 971 /* Partition doesn't exist (or other error) */ 972 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 973 return NULL; 974 975 /* Fetch address and length from reply */ 976 addr = *((u16 *)cmd.buffer); 977 len = cmd.buffer[3] << 2; 978 /* Calucluate total length to allocate, including the 17 bytes 979 * for "sdb-partition-XX" that we append at the end of the buffer 980 */ 981 tlen = sizeof(struct property) + len + 18; 982 983 prop = kzalloc(tlen, GFP_KERNEL); 984 if (prop == NULL) 985 return NULL; 986 hdr = (struct smu_sdbp_header *)(prop + 1); 987 prop->name = ((char *)prop) + tlen - 18; 988 sprintf(prop->name, "sdb-partition-%02x", id); 989 prop->length = len; 990 prop->value = hdr; 991 prop->next = NULL; 992 993 /* Read the datablock */ 994 if (smu_read_datablock((u8 *)hdr, addr, len)) { 995 printk(KERN_DEBUG "SMU: datablock read failed while reading " 996 "partition %02x !\n", id); 997 goto failure; 998 } 999 1000 /* Got it, check a few things and create the property */ 1001 if (hdr->id != id) { 1002 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 1003 "%02x !\n", id, hdr->id); 1004 goto failure; 1005 } 1006 if (prom_add_property(smu->of_node, prop)) { 1007 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 1008 "property !\n", id); 1009 goto failure; 1010 } 1011 1012 return hdr; 1013 failure: 1014 kfree(prop); 1015 return NULL; 1016 } 1017 1018 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 1019 * when interruptible is 1 1020 */ 1021 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 1022 unsigned int *size, int interruptible) 1023 { 1024 char pname[32]; 1025 const struct smu_sdbp_header *part; 1026 1027 if (!smu) 1028 return NULL; 1029 1030 sprintf(pname, "sdb-partition-%02x", id); 1031 1032 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 1033 1034 if (interruptible) { 1035 int rc; 1036 rc = mutex_lock_interruptible(&smu_part_access); 1037 if (rc) 1038 return ERR_PTR(rc); 1039 } else 1040 mutex_lock(&smu_part_access); 1041 1042 part = of_get_property(smu->of_node, pname, size); 1043 if (part == NULL) { 1044 DPRINTK("trying to extract from SMU ...\n"); 1045 part = smu_create_sdb_partition(id); 1046 if (part != NULL && size) 1047 *size = part->len << 2; 1048 } 1049 mutex_unlock(&smu_part_access); 1050 return part; 1051 } 1052 1053 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1054 { 1055 return __smu_get_sdb_partition(id, size, 0); 1056 } 1057 EXPORT_SYMBOL(smu_get_sdb_partition); 1058 1059 1060 /* 1061 * Userland driver interface 1062 */ 1063 1064 1065 static LIST_HEAD(smu_clist); 1066 static DEFINE_SPINLOCK(smu_clist_lock); 1067 1068 enum smu_file_mode { 1069 smu_file_commands, 1070 smu_file_events, 1071 smu_file_closing 1072 }; 1073 1074 struct smu_private 1075 { 1076 struct list_head list; 1077 enum smu_file_mode mode; 1078 int busy; 1079 struct smu_cmd cmd; 1080 spinlock_t lock; 1081 wait_queue_head_t wait; 1082 u8 buffer[SMU_MAX_DATA]; 1083 }; 1084 1085 1086 static int smu_open(struct inode *inode, struct file *file) 1087 { 1088 struct smu_private *pp; 1089 unsigned long flags; 1090 1091 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1092 if (pp == 0) 1093 return -ENOMEM; 1094 spin_lock_init(&pp->lock); 1095 pp->mode = smu_file_commands; 1096 init_waitqueue_head(&pp->wait); 1097 1098 mutex_lock(&smu_mutex); 1099 spin_lock_irqsave(&smu_clist_lock, flags); 1100 list_add(&pp->list, &smu_clist); 1101 spin_unlock_irqrestore(&smu_clist_lock, flags); 1102 file->private_data = pp; 1103 mutex_unlock(&smu_mutex); 1104 1105 return 0; 1106 } 1107 1108 1109 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1110 { 1111 struct smu_private *pp = misc; 1112 1113 wake_up_all(&pp->wait); 1114 } 1115 1116 1117 static ssize_t smu_write(struct file *file, const char __user *buf, 1118 size_t count, loff_t *ppos) 1119 { 1120 struct smu_private *pp = file->private_data; 1121 unsigned long flags; 1122 struct smu_user_cmd_hdr hdr; 1123 int rc = 0; 1124 1125 if (pp->busy) 1126 return -EBUSY; 1127 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1128 return -EFAULT; 1129 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1130 pp->mode = smu_file_events; 1131 return 0; 1132 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1133 const struct smu_sdbp_header *part; 1134 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1135 if (part == NULL) 1136 return -EINVAL; 1137 else if (IS_ERR(part)) 1138 return PTR_ERR(part); 1139 return 0; 1140 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1141 return -EINVAL; 1142 else if (pp->mode != smu_file_commands) 1143 return -EBADFD; 1144 else if (hdr.data_len > SMU_MAX_DATA) 1145 return -EINVAL; 1146 1147 spin_lock_irqsave(&pp->lock, flags); 1148 if (pp->busy) { 1149 spin_unlock_irqrestore(&pp->lock, flags); 1150 return -EBUSY; 1151 } 1152 pp->busy = 1; 1153 pp->cmd.status = 1; 1154 spin_unlock_irqrestore(&pp->lock, flags); 1155 1156 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1157 pp->busy = 0; 1158 return -EFAULT; 1159 } 1160 1161 pp->cmd.cmd = hdr.cmd; 1162 pp->cmd.data_len = hdr.data_len; 1163 pp->cmd.reply_len = SMU_MAX_DATA; 1164 pp->cmd.data_buf = pp->buffer; 1165 pp->cmd.reply_buf = pp->buffer; 1166 pp->cmd.done = smu_user_cmd_done; 1167 pp->cmd.misc = pp; 1168 rc = smu_queue_cmd(&pp->cmd); 1169 if (rc < 0) 1170 return rc; 1171 return count; 1172 } 1173 1174 1175 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1176 char __user *buf, size_t count) 1177 { 1178 DECLARE_WAITQUEUE(wait, current); 1179 struct smu_user_reply_hdr hdr; 1180 unsigned long flags; 1181 int size, rc = 0; 1182 1183 if (!pp->busy) 1184 return 0; 1185 if (count < sizeof(struct smu_user_reply_hdr)) 1186 return -EOVERFLOW; 1187 spin_lock_irqsave(&pp->lock, flags); 1188 if (pp->cmd.status == 1) { 1189 if (file->f_flags & O_NONBLOCK) { 1190 spin_unlock_irqrestore(&pp->lock, flags); 1191 return -EAGAIN; 1192 } 1193 add_wait_queue(&pp->wait, &wait); 1194 for (;;) { 1195 set_current_state(TASK_INTERRUPTIBLE); 1196 rc = 0; 1197 if (pp->cmd.status != 1) 1198 break; 1199 rc = -ERESTARTSYS; 1200 if (signal_pending(current)) 1201 break; 1202 spin_unlock_irqrestore(&pp->lock, flags); 1203 schedule(); 1204 spin_lock_irqsave(&pp->lock, flags); 1205 } 1206 set_current_state(TASK_RUNNING); 1207 remove_wait_queue(&pp->wait, &wait); 1208 } 1209 spin_unlock_irqrestore(&pp->lock, flags); 1210 if (rc) 1211 return rc; 1212 if (pp->cmd.status != 0) 1213 pp->cmd.reply_len = 0; 1214 size = sizeof(hdr) + pp->cmd.reply_len; 1215 if (count < size) 1216 size = count; 1217 rc = size; 1218 hdr.status = pp->cmd.status; 1219 hdr.reply_len = pp->cmd.reply_len; 1220 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1221 return -EFAULT; 1222 size -= sizeof(hdr); 1223 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1224 return -EFAULT; 1225 pp->busy = 0; 1226 1227 return rc; 1228 } 1229 1230 1231 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1232 char __user *buf, size_t count) 1233 { 1234 /* Not implemented */ 1235 msleep_interruptible(1000); 1236 return 0; 1237 } 1238 1239 1240 static ssize_t smu_read(struct file *file, char __user *buf, 1241 size_t count, loff_t *ppos) 1242 { 1243 struct smu_private *pp = file->private_data; 1244 1245 if (pp->mode == smu_file_commands) 1246 return smu_read_command(file, pp, buf, count); 1247 if (pp->mode == smu_file_events) 1248 return smu_read_events(file, pp, buf, count); 1249 1250 return -EBADFD; 1251 } 1252 1253 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1254 { 1255 struct smu_private *pp = file->private_data; 1256 unsigned int mask = 0; 1257 unsigned long flags; 1258 1259 if (pp == 0) 1260 return 0; 1261 1262 if (pp->mode == smu_file_commands) { 1263 poll_wait(file, &pp->wait, wait); 1264 1265 spin_lock_irqsave(&pp->lock, flags); 1266 if (pp->busy && pp->cmd.status != 1) 1267 mask |= POLLIN; 1268 spin_unlock_irqrestore(&pp->lock, flags); 1269 } if (pp->mode == smu_file_events) { 1270 /* Not yet implemented */ 1271 } 1272 return mask; 1273 } 1274 1275 static int smu_release(struct inode *inode, struct file *file) 1276 { 1277 struct smu_private *pp = file->private_data; 1278 unsigned long flags; 1279 unsigned int busy; 1280 1281 if (pp == 0) 1282 return 0; 1283 1284 file->private_data = NULL; 1285 1286 /* Mark file as closing to avoid races with new request */ 1287 spin_lock_irqsave(&pp->lock, flags); 1288 pp->mode = smu_file_closing; 1289 busy = pp->busy; 1290 1291 /* Wait for any pending request to complete */ 1292 if (busy && pp->cmd.status == 1) { 1293 DECLARE_WAITQUEUE(wait, current); 1294 1295 add_wait_queue(&pp->wait, &wait); 1296 for (;;) { 1297 set_current_state(TASK_UNINTERRUPTIBLE); 1298 if (pp->cmd.status != 1) 1299 break; 1300 spin_unlock_irqrestore(&pp->lock, flags); 1301 schedule(); 1302 spin_lock_irqsave(&pp->lock, flags); 1303 } 1304 set_current_state(TASK_RUNNING); 1305 remove_wait_queue(&pp->wait, &wait); 1306 } 1307 spin_unlock_irqrestore(&pp->lock, flags); 1308 1309 spin_lock_irqsave(&smu_clist_lock, flags); 1310 list_del(&pp->list); 1311 spin_unlock_irqrestore(&smu_clist_lock, flags); 1312 kfree(pp); 1313 1314 return 0; 1315 } 1316 1317 1318 static const struct file_operations smu_device_fops = { 1319 .llseek = no_llseek, 1320 .read = smu_read, 1321 .write = smu_write, 1322 .poll = smu_fpoll, 1323 .open = smu_open, 1324 .release = smu_release, 1325 }; 1326 1327 static struct miscdevice pmu_device = { 1328 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1329 }; 1330 1331 static int smu_device_init(void) 1332 { 1333 if (!smu) 1334 return -ENODEV; 1335 if (misc_register(&pmu_device) < 0) 1336 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1337 return 0; 1338 } 1339 device_initcall(smu_device_init); 1340