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/smp_lock.h> 23 #include <linux/types.h> 24 #include <linux/kernel.h> 25 #include <linux/device.h> 26 #include <linux/dmapool.h> 27 #include <linux/bootmem.h> 28 #include <linux/vmalloc.h> 29 #include <linux/highmem.h> 30 #include <linux/jiffies.h> 31 #include <linux/interrupt.h> 32 #include <linux/rtc.h> 33 #include <linux/completion.h> 34 #include <linux/miscdevice.h> 35 #include <linux/delay.h> 36 #include <linux/sysdev.h> 37 #include <linux/poll.h> 38 #include <linux/mutex.h> 39 #include <linux/of_device.h> 40 #include <linux/of_platform.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 of_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 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: %02x %02x %02x %02x %02x %02x %02x %02x\n", 125 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 126 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 127 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 128 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 129 130 /* Fill the SMU command buffer */ 131 smu->cmd_buf->cmd = cmd->cmd; 132 smu->cmd_buf->length = cmd->data_len; 133 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 134 135 /* Flush command and data to RAM */ 136 faddr = (unsigned long)smu->cmd_buf; 137 fend = faddr + smu->cmd_buf->length + 2; 138 flush_inval_dcache_range(faddr, fend); 139 140 141 /* We also disable NAP mode for the duration of the command 142 * on U3 based machines. 143 * This is slightly racy as it can be written back to 1 by a sysctl 144 * but that never happens in practice. There seem to be an issue with 145 * U3 based machines such as the iMac G5 where napping for the 146 * whole duration of the command prevents the SMU from fetching it 147 * from memory. This might be related to the strange i2c based 148 * mechanism the SMU uses to access memory. 149 */ 150 if (smu->broken_nap) 151 powersave_nap = 0; 152 153 /* This isn't exactly a DMA mapping here, I suspect 154 * the SMU is actually communicating with us via i2c to the 155 * northbridge or the CPU to access RAM. 156 */ 157 writel(smu->cmd_buf_abs, smu->db_buf); 158 159 /* Ring the SMU doorbell */ 160 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 161 } 162 163 164 static irqreturn_t smu_db_intr(int irq, void *arg) 165 { 166 unsigned long flags; 167 struct smu_cmd *cmd; 168 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 169 void *misc = NULL; 170 u8 gpio; 171 int rc = 0; 172 173 /* SMU completed the command, well, we hope, let's make sure 174 * of it 175 */ 176 spin_lock_irqsave(&smu->lock, flags); 177 178 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 179 if ((gpio & 7) != 7) { 180 spin_unlock_irqrestore(&smu->lock, flags); 181 return IRQ_HANDLED; 182 } 183 184 cmd = smu->cmd_cur; 185 smu->cmd_cur = NULL; 186 if (cmd == NULL) 187 goto bail; 188 189 if (rc == 0) { 190 unsigned long faddr; 191 int reply_len; 192 u8 ack; 193 194 /* CPU might have brought back the cache line, so we need 195 * to flush again before peeking at the SMU response. We 196 * flush the entire buffer for now as we haven't read the 197 * reply length (it's only 2 cache lines anyway) 198 */ 199 faddr = (unsigned long)smu->cmd_buf; 200 flush_inval_dcache_range(faddr, faddr + 256); 201 202 /* Now check ack */ 203 ack = (~cmd->cmd) & 0xff; 204 if (ack != smu->cmd_buf->cmd) { 205 DPRINTK("SMU: incorrect ack, want %x got %x\n", 206 ack, smu->cmd_buf->cmd); 207 rc = -EIO; 208 } 209 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 210 DPRINTK("SMU: reply len: %d\n", reply_len); 211 if (reply_len > cmd->reply_len) { 212 printk(KERN_WARNING "SMU: reply buffer too small," 213 "got %d bytes for a %d bytes buffer\n", 214 reply_len, cmd->reply_len); 215 reply_len = cmd->reply_len; 216 } 217 cmd->reply_len = reply_len; 218 if (cmd->reply_buf && reply_len) 219 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 220 } 221 222 /* Now complete the command. Write status last in order as we lost 223 * ownership of the command structure as soon as it's no longer -1 224 */ 225 done = cmd->done; 226 misc = cmd->misc; 227 mb(); 228 cmd->status = rc; 229 230 /* Re-enable NAP mode */ 231 if (smu->broken_nap) 232 powersave_nap = 1; 233 bail: 234 /* Start next command if any */ 235 smu_start_cmd(); 236 spin_unlock_irqrestore(&smu->lock, flags); 237 238 /* Call command completion handler if any */ 239 if (done) 240 done(cmd, misc); 241 242 /* It's an edge interrupt, nothing to do */ 243 return IRQ_HANDLED; 244 } 245 246 247 static irqreturn_t smu_msg_intr(int irq, void *arg) 248 { 249 /* I don't quite know what to do with this one, we seem to never 250 * receive it, so I suspect we have to arm it someway in the SMU 251 * to start getting events that way. 252 */ 253 254 printk(KERN_INFO "SMU: message interrupt !\n"); 255 256 /* It's an edge interrupt, nothing to do */ 257 return IRQ_HANDLED; 258 } 259 260 261 /* 262 * Queued command management. 263 * 264 */ 265 266 int smu_queue_cmd(struct smu_cmd *cmd) 267 { 268 unsigned long flags; 269 270 if (smu == NULL) 271 return -ENODEV; 272 if (cmd->data_len > SMU_MAX_DATA || 273 cmd->reply_len > SMU_MAX_DATA) 274 return -EINVAL; 275 276 cmd->status = 1; 277 spin_lock_irqsave(&smu->lock, flags); 278 list_add_tail(&cmd->link, &smu->cmd_list); 279 if (smu->cmd_cur == NULL) 280 smu_start_cmd(); 281 spin_unlock_irqrestore(&smu->lock, flags); 282 283 /* Workaround for early calls when irq isn't available */ 284 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 285 smu_spinwait_cmd(cmd); 286 287 return 0; 288 } 289 EXPORT_SYMBOL(smu_queue_cmd); 290 291 292 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 293 unsigned int data_len, 294 void (*done)(struct smu_cmd *cmd, void *misc), 295 void *misc, ...) 296 { 297 struct smu_cmd *cmd = &scmd->cmd; 298 va_list list; 299 int i; 300 301 if (data_len > sizeof(scmd->buffer)) 302 return -EINVAL; 303 304 memset(scmd, 0, sizeof(*scmd)); 305 cmd->cmd = command; 306 cmd->data_len = data_len; 307 cmd->data_buf = scmd->buffer; 308 cmd->reply_len = sizeof(scmd->buffer); 309 cmd->reply_buf = scmd->buffer; 310 cmd->done = done; 311 cmd->misc = misc; 312 313 va_start(list, misc); 314 for (i = 0; i < data_len; ++i) 315 scmd->buffer[i] = (u8)va_arg(list, int); 316 va_end(list); 317 318 return smu_queue_cmd(cmd); 319 } 320 EXPORT_SYMBOL(smu_queue_simple); 321 322 323 void smu_poll(void) 324 { 325 u8 gpio; 326 327 if (smu == NULL) 328 return; 329 330 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 331 if ((gpio & 7) == 7) 332 smu_db_intr(smu->db_irq, smu); 333 } 334 EXPORT_SYMBOL(smu_poll); 335 336 337 void smu_done_complete(struct smu_cmd *cmd, void *misc) 338 { 339 struct completion *comp = misc; 340 341 complete(comp); 342 } 343 EXPORT_SYMBOL(smu_done_complete); 344 345 346 void smu_spinwait_cmd(struct smu_cmd *cmd) 347 { 348 while(cmd->status == 1) 349 smu_poll(); 350 } 351 EXPORT_SYMBOL(smu_spinwait_cmd); 352 353 354 /* RTC low level commands */ 355 static inline int bcd2hex (int n) 356 { 357 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 358 } 359 360 361 static inline int hex2bcd (int n) 362 { 363 return ((n / 10) << 4) + (n % 10); 364 } 365 366 367 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 368 struct rtc_time *time) 369 { 370 cmd_buf->cmd = 0x8e; 371 cmd_buf->length = 8; 372 cmd_buf->data[0] = 0x80; 373 cmd_buf->data[1] = hex2bcd(time->tm_sec); 374 cmd_buf->data[2] = hex2bcd(time->tm_min); 375 cmd_buf->data[3] = hex2bcd(time->tm_hour); 376 cmd_buf->data[4] = time->tm_wday; 377 cmd_buf->data[5] = hex2bcd(time->tm_mday); 378 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 379 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 380 } 381 382 383 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 384 { 385 struct smu_simple_cmd cmd; 386 int rc; 387 388 if (smu == NULL) 389 return -ENODEV; 390 391 memset(time, 0, sizeof(struct rtc_time)); 392 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 393 SMU_CMD_RTC_GET_DATETIME); 394 if (rc) 395 return rc; 396 smu_spinwait_simple(&cmd); 397 398 time->tm_sec = bcd2hex(cmd.buffer[0]); 399 time->tm_min = bcd2hex(cmd.buffer[1]); 400 time->tm_hour = bcd2hex(cmd.buffer[2]); 401 time->tm_wday = bcd2hex(cmd.buffer[3]); 402 time->tm_mday = bcd2hex(cmd.buffer[4]); 403 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 404 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 405 406 return 0; 407 } 408 409 410 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 411 { 412 struct smu_simple_cmd cmd; 413 int rc; 414 415 if (smu == NULL) 416 return -ENODEV; 417 418 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 419 SMU_CMD_RTC_SET_DATETIME, 420 hex2bcd(time->tm_sec), 421 hex2bcd(time->tm_min), 422 hex2bcd(time->tm_hour), 423 time->tm_wday, 424 hex2bcd(time->tm_mday), 425 hex2bcd(time->tm_mon) + 1, 426 hex2bcd(time->tm_year - 100)); 427 if (rc) 428 return rc; 429 smu_spinwait_simple(&cmd); 430 431 return 0; 432 } 433 434 435 void smu_shutdown(void) 436 { 437 struct smu_simple_cmd cmd; 438 439 if (smu == NULL) 440 return; 441 442 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 443 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 444 return; 445 smu_spinwait_simple(&cmd); 446 for (;;) 447 ; 448 } 449 450 451 void smu_restart(void) 452 { 453 struct smu_simple_cmd cmd; 454 455 if (smu == NULL) 456 return; 457 458 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 459 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 460 return; 461 smu_spinwait_simple(&cmd); 462 for (;;) 463 ; 464 } 465 466 467 int smu_present(void) 468 { 469 return smu != NULL; 470 } 471 EXPORT_SYMBOL(smu_present); 472 473 474 int __init smu_init (void) 475 { 476 struct device_node *np; 477 const u32 *data; 478 int ret = 0; 479 480 np = of_find_node_by_type(NULL, "smu"); 481 if (np == NULL) 482 return -ENODEV; 483 484 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR); 485 486 if (smu_cmdbuf_abs == 0) { 487 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 488 ret = -EINVAL; 489 goto fail_np; 490 } 491 492 smu = alloc_bootmem(sizeof(struct smu_device)); 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 ret = -ENXIO; 511 goto fail_bootmem; 512 } 513 data = of_get_property(smu->db_node, "reg", NULL); 514 if (data == NULL) { 515 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 516 ret = -ENXIO; 517 goto fail_db_node; 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 ret = -ENXIO; 552 goto fail_msg_node; 553 } 554 555 /* U3 has an issue with NAP mode when issuing SMU commands */ 556 smu->broken_nap = pmac_get_uninorth_variant() < 4; 557 if (smu->broken_nap) 558 printk(KERN_INFO "SMU: using NAP mode workaround\n"); 559 560 sys_ctrler = SYS_CTRLER_SMU; 561 return 0; 562 563 fail_msg_node: 564 if (smu->msg_node) 565 of_node_put(smu->msg_node); 566 fail_db_node: 567 of_node_put(smu->db_node); 568 fail_bootmem: 569 free_bootmem((unsigned long)smu, sizeof(struct smu_device)); 570 smu = NULL; 571 fail_np: 572 of_node_put(np); 573 return ret; 574 } 575 576 577 static int smu_late_init(void) 578 { 579 if (!smu) 580 return 0; 581 582 init_timer(&smu->i2c_timer); 583 smu->i2c_timer.function = smu_i2c_retry; 584 smu->i2c_timer.data = (unsigned long)smu; 585 586 if (smu->db_node) { 587 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); 588 if (smu->db_irq == NO_IRQ) 589 printk(KERN_ERR "smu: failed to map irq for node %s\n", 590 smu->db_node->full_name); 591 } 592 if (smu->msg_node) { 593 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); 594 if (smu->msg_irq == NO_IRQ) 595 printk(KERN_ERR "smu: failed to map irq for node %s\n", 596 smu->msg_node->full_name); 597 } 598 599 /* 600 * Try to request the interrupts 601 */ 602 603 if (smu->db_irq != NO_IRQ) { 604 if (request_irq(smu->db_irq, smu_db_intr, 605 IRQF_SHARED, "SMU doorbell", smu) < 0) { 606 printk(KERN_WARNING "SMU: can't " 607 "request interrupt %d\n", 608 smu->db_irq); 609 smu->db_irq = NO_IRQ; 610 } 611 } 612 613 if (smu->msg_irq != NO_IRQ) { 614 if (request_irq(smu->msg_irq, smu_msg_intr, 615 IRQF_SHARED, "SMU message", smu) < 0) { 616 printk(KERN_WARNING "SMU: can't " 617 "request interrupt %d\n", 618 smu->msg_irq); 619 smu->msg_irq = NO_IRQ; 620 } 621 } 622 623 smu_irq_inited = 1; 624 return 0; 625 } 626 /* This has to be before arch_initcall as the low i2c stuff relies on the 627 * above having been done before we reach arch_initcalls 628 */ 629 core_initcall(smu_late_init); 630 631 /* 632 * sysfs visibility 633 */ 634 635 static void smu_expose_childs(struct work_struct *unused) 636 { 637 struct device_node *np; 638 639 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 640 if (of_device_is_compatible(np, "smu-sensors")) 641 of_platform_device_create(np, "smu-sensors", 642 &smu->of_dev->dev); 643 } 644 645 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 646 647 static int smu_platform_probe(struct of_device* dev, 648 const struct of_device_id *match) 649 { 650 if (!smu) 651 return -ENODEV; 652 smu->of_dev = dev; 653 654 /* 655 * Ok, we are matched, now expose all i2c busses. We have to defer 656 * that unfortunately or it would deadlock inside the device model 657 */ 658 schedule_work(&smu_expose_childs_work); 659 660 return 0; 661 } 662 663 static struct of_device_id smu_platform_match[] = 664 { 665 { 666 .type = "smu", 667 }, 668 {}, 669 }; 670 671 static struct of_platform_driver smu_of_platform_driver = 672 { 673 .name = "smu", 674 .match_table = smu_platform_match, 675 .probe = smu_platform_probe, 676 }; 677 678 static int __init smu_init_sysfs(void) 679 { 680 /* 681 * Due to sysfs bogosity, a sysdev is not a real device, so 682 * we should in fact create both if we want sysdev semantics 683 * for power management. 684 * For now, we don't power manage machines with an SMU chip, 685 * I'm a bit too far from figuring out how that works with those 686 * new chipsets, but that will come back and bite us 687 */ 688 of_register_platform_driver(&smu_of_platform_driver); 689 return 0; 690 } 691 692 device_initcall(smu_init_sysfs); 693 694 struct of_device *smu_get_ofdev(void) 695 { 696 if (!smu) 697 return NULL; 698 return smu->of_dev; 699 } 700 701 EXPORT_SYMBOL_GPL(smu_get_ofdev); 702 703 /* 704 * i2c interface 705 */ 706 707 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 708 { 709 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 710 void *misc = cmd->misc; 711 unsigned long flags; 712 713 /* Check for read case */ 714 if (!fail && cmd->read) { 715 if (cmd->pdata[0] < 1) 716 fail = 1; 717 else 718 memcpy(cmd->info.data, &cmd->pdata[1], 719 cmd->info.datalen); 720 } 721 722 DPRINTK("SMU: completing, success: %d\n", !fail); 723 724 /* Update status and mark no pending i2c command with lock 725 * held so nobody comes in while we dequeue an eventual 726 * pending next i2c command 727 */ 728 spin_lock_irqsave(&smu->lock, flags); 729 smu->cmd_i2c_cur = NULL; 730 wmb(); 731 cmd->status = fail ? -EIO : 0; 732 733 /* Is there another i2c command waiting ? */ 734 if (!list_empty(&smu->cmd_i2c_list)) { 735 struct smu_i2c_cmd *newcmd; 736 737 /* Fetch it, new current, remove from list */ 738 newcmd = list_entry(smu->cmd_i2c_list.next, 739 struct smu_i2c_cmd, link); 740 smu->cmd_i2c_cur = newcmd; 741 list_del(&cmd->link); 742 743 /* Queue with low level smu */ 744 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 745 if (smu->cmd_cur == NULL) 746 smu_start_cmd(); 747 } 748 spin_unlock_irqrestore(&smu->lock, flags); 749 750 /* Call command completion handler if any */ 751 if (done) 752 done(cmd, misc); 753 754 } 755 756 757 static void smu_i2c_retry(unsigned long data) 758 { 759 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 760 761 DPRINTK("SMU: i2c failure, requeuing...\n"); 762 763 /* requeue command simply by resetting reply_len */ 764 cmd->pdata[0] = 0xff; 765 cmd->scmd.reply_len = sizeof(cmd->pdata); 766 smu_queue_cmd(&cmd->scmd); 767 } 768 769 770 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 771 { 772 struct smu_i2c_cmd *cmd = misc; 773 int fail = 0; 774 775 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 776 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 777 778 /* Check for possible status */ 779 if (scmd->status < 0) 780 fail = 1; 781 else if (cmd->read) { 782 if (cmd->stage == 0) 783 fail = cmd->pdata[0] != 0; 784 else 785 fail = cmd->pdata[0] >= 0x80; 786 } else { 787 fail = cmd->pdata[0] != 0; 788 } 789 790 /* Handle failures by requeuing command, after 5ms interval 791 */ 792 if (fail && --cmd->retries > 0) { 793 DPRINTK("SMU: i2c failure, starting timer...\n"); 794 BUG_ON(cmd != smu->cmd_i2c_cur); 795 if (!smu_irq_inited) { 796 mdelay(5); 797 smu_i2c_retry(0); 798 return; 799 } 800 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 801 return; 802 } 803 804 /* If failure or stage 1, command is complete */ 805 if (fail || cmd->stage != 0) { 806 smu_i2c_complete_command(cmd, fail); 807 return; 808 } 809 810 DPRINTK("SMU: going to stage 1\n"); 811 812 /* Ok, initial command complete, now poll status */ 813 scmd->reply_buf = cmd->pdata; 814 scmd->reply_len = sizeof(cmd->pdata); 815 scmd->data_buf = cmd->pdata; 816 scmd->data_len = 1; 817 cmd->pdata[0] = 0; 818 cmd->stage = 1; 819 cmd->retries = 20; 820 smu_queue_cmd(scmd); 821 } 822 823 824 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 825 { 826 unsigned long flags; 827 828 if (smu == NULL) 829 return -ENODEV; 830 831 /* Fill most fields of scmd */ 832 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 833 cmd->scmd.done = smu_i2c_low_completion; 834 cmd->scmd.misc = cmd; 835 cmd->scmd.reply_buf = cmd->pdata; 836 cmd->scmd.reply_len = sizeof(cmd->pdata); 837 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 838 cmd->scmd.status = 1; 839 cmd->stage = 0; 840 cmd->pdata[0] = 0xff; 841 cmd->retries = 20; 842 cmd->status = 1; 843 844 /* Check transfer type, sanitize some "info" fields 845 * based on transfer type and do more checking 846 */ 847 cmd->info.caddr = cmd->info.devaddr; 848 cmd->read = cmd->info.devaddr & 0x01; 849 switch(cmd->info.type) { 850 case SMU_I2C_TRANSFER_SIMPLE: 851 memset(&cmd->info.sublen, 0, 4); 852 break; 853 case SMU_I2C_TRANSFER_COMBINED: 854 cmd->info.devaddr &= 0xfe; 855 case SMU_I2C_TRANSFER_STDSUB: 856 if (cmd->info.sublen > 3) 857 return -EINVAL; 858 break; 859 default: 860 return -EINVAL; 861 } 862 863 /* Finish setting up command based on transfer direction 864 */ 865 if (cmd->read) { 866 if (cmd->info.datalen > SMU_I2C_READ_MAX) 867 return -EINVAL; 868 memset(cmd->info.data, 0xff, cmd->info.datalen); 869 cmd->scmd.data_len = 9; 870 } else { 871 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 872 return -EINVAL; 873 cmd->scmd.data_len = 9 + cmd->info.datalen; 874 } 875 876 DPRINTK("SMU: i2c enqueuing command\n"); 877 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 878 cmd->read ? "read" : "write", cmd->info.datalen, 879 cmd->info.bus, cmd->info.caddr, 880 cmd->info.subaddr[0], cmd->info.type); 881 882 883 /* Enqueue command in i2c list, and if empty, enqueue also in 884 * main command list 885 */ 886 spin_lock_irqsave(&smu->lock, flags); 887 if (smu->cmd_i2c_cur == NULL) { 888 smu->cmd_i2c_cur = cmd; 889 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 890 if (smu->cmd_cur == NULL) 891 smu_start_cmd(); 892 } else 893 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 894 spin_unlock_irqrestore(&smu->lock, flags); 895 896 return 0; 897 } 898 899 /* 900 * Handling of "partitions" 901 */ 902 903 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 904 { 905 DECLARE_COMPLETION_ONSTACK(comp); 906 unsigned int chunk; 907 struct smu_cmd cmd; 908 int rc; 909 u8 params[8]; 910 911 /* We currently use a chunk size of 0xe. We could check the 912 * SMU firmware version and use bigger sizes though 913 */ 914 chunk = 0xe; 915 916 while (len) { 917 unsigned int clen = min(len, chunk); 918 919 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 920 cmd.data_len = 7; 921 cmd.data_buf = params; 922 cmd.reply_len = chunk; 923 cmd.reply_buf = dest; 924 cmd.done = smu_done_complete; 925 cmd.misc = ∁ 926 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 927 params[1] = 0x4; 928 *((u32 *)¶ms[2]) = addr; 929 params[6] = clen; 930 931 rc = smu_queue_cmd(&cmd); 932 if (rc) 933 return rc; 934 wait_for_completion(&comp); 935 if (cmd.status != 0) 936 return rc; 937 if (cmd.reply_len != clen) { 938 printk(KERN_DEBUG "SMU: short read in " 939 "smu_read_datablock, got: %d, want: %d\n", 940 cmd.reply_len, clen); 941 return -EIO; 942 } 943 len -= clen; 944 addr += clen; 945 dest += clen; 946 } 947 return 0; 948 } 949 950 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 951 { 952 DECLARE_COMPLETION_ONSTACK(comp); 953 struct smu_simple_cmd cmd; 954 unsigned int addr, len, tlen; 955 struct smu_sdbp_header *hdr; 956 struct property *prop; 957 958 /* First query the partition info */ 959 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 960 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 961 smu_done_complete, &comp, 962 SMU_CMD_PARTITION_LATEST, id); 963 wait_for_completion(&comp); 964 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 965 cmd.cmd.status, cmd.cmd.reply_len); 966 967 /* Partition doesn't exist (or other error) */ 968 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 969 return NULL; 970 971 /* Fetch address and length from reply */ 972 addr = *((u16 *)cmd.buffer); 973 len = cmd.buffer[3] << 2; 974 /* Calucluate total length to allocate, including the 17 bytes 975 * for "sdb-partition-XX" that we append at the end of the buffer 976 */ 977 tlen = sizeof(struct property) + len + 18; 978 979 prop = kzalloc(tlen, GFP_KERNEL); 980 if (prop == NULL) 981 return NULL; 982 hdr = (struct smu_sdbp_header *)(prop + 1); 983 prop->name = ((char *)prop) + tlen - 18; 984 sprintf(prop->name, "sdb-partition-%02x", id); 985 prop->length = len; 986 prop->value = hdr; 987 prop->next = NULL; 988 989 /* Read the datablock */ 990 if (smu_read_datablock((u8 *)hdr, addr, len)) { 991 printk(KERN_DEBUG "SMU: datablock read failed while reading " 992 "partition %02x !\n", id); 993 goto failure; 994 } 995 996 /* Got it, check a few things and create the property */ 997 if (hdr->id != id) { 998 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 999 "%02x !\n", id, hdr->id); 1000 goto failure; 1001 } 1002 if (prom_add_property(smu->of_node, prop)) { 1003 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 1004 "property !\n", id); 1005 goto failure; 1006 } 1007 1008 return hdr; 1009 failure: 1010 kfree(prop); 1011 return NULL; 1012 } 1013 1014 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 1015 * when interruptible is 1 1016 */ 1017 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 1018 unsigned int *size, int interruptible) 1019 { 1020 char pname[32]; 1021 const struct smu_sdbp_header *part; 1022 1023 if (!smu) 1024 return NULL; 1025 1026 sprintf(pname, "sdb-partition-%02x", id); 1027 1028 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 1029 1030 if (interruptible) { 1031 int rc; 1032 rc = mutex_lock_interruptible(&smu_part_access); 1033 if (rc) 1034 return ERR_PTR(rc); 1035 } else 1036 mutex_lock(&smu_part_access); 1037 1038 part = of_get_property(smu->of_node, pname, size); 1039 if (part == NULL) { 1040 DPRINTK("trying to extract from SMU ...\n"); 1041 part = smu_create_sdb_partition(id); 1042 if (part != NULL && size) 1043 *size = part->len << 2; 1044 } 1045 mutex_unlock(&smu_part_access); 1046 return part; 1047 } 1048 1049 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1050 { 1051 return __smu_get_sdb_partition(id, size, 0); 1052 } 1053 EXPORT_SYMBOL(smu_get_sdb_partition); 1054 1055 1056 /* 1057 * Userland driver interface 1058 */ 1059 1060 1061 static LIST_HEAD(smu_clist); 1062 static DEFINE_SPINLOCK(smu_clist_lock); 1063 1064 enum smu_file_mode { 1065 smu_file_commands, 1066 smu_file_events, 1067 smu_file_closing 1068 }; 1069 1070 struct smu_private 1071 { 1072 struct list_head list; 1073 enum smu_file_mode mode; 1074 int busy; 1075 struct smu_cmd cmd; 1076 spinlock_t lock; 1077 wait_queue_head_t wait; 1078 u8 buffer[SMU_MAX_DATA]; 1079 }; 1080 1081 1082 static int smu_open(struct inode *inode, struct file *file) 1083 { 1084 struct smu_private *pp; 1085 unsigned long flags; 1086 1087 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1088 if (pp == 0) 1089 return -ENOMEM; 1090 spin_lock_init(&pp->lock); 1091 pp->mode = smu_file_commands; 1092 init_waitqueue_head(&pp->wait); 1093 1094 lock_kernel(); 1095 spin_lock_irqsave(&smu_clist_lock, flags); 1096 list_add(&pp->list, &smu_clist); 1097 spin_unlock_irqrestore(&smu_clist_lock, flags); 1098 file->private_data = pp; 1099 unlock_kernel(); 1100 1101 return 0; 1102 } 1103 1104 1105 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1106 { 1107 struct smu_private *pp = misc; 1108 1109 wake_up_all(&pp->wait); 1110 } 1111 1112 1113 static ssize_t smu_write(struct file *file, const char __user *buf, 1114 size_t count, loff_t *ppos) 1115 { 1116 struct smu_private *pp = file->private_data; 1117 unsigned long flags; 1118 struct smu_user_cmd_hdr hdr; 1119 int rc = 0; 1120 1121 if (pp->busy) 1122 return -EBUSY; 1123 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1124 return -EFAULT; 1125 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1126 pp->mode = smu_file_events; 1127 return 0; 1128 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1129 const struct smu_sdbp_header *part; 1130 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1131 if (part == NULL) 1132 return -EINVAL; 1133 else if (IS_ERR(part)) 1134 return PTR_ERR(part); 1135 return 0; 1136 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1137 return -EINVAL; 1138 else if (pp->mode != smu_file_commands) 1139 return -EBADFD; 1140 else if (hdr.data_len > SMU_MAX_DATA) 1141 return -EINVAL; 1142 1143 spin_lock_irqsave(&pp->lock, flags); 1144 if (pp->busy) { 1145 spin_unlock_irqrestore(&pp->lock, flags); 1146 return -EBUSY; 1147 } 1148 pp->busy = 1; 1149 pp->cmd.status = 1; 1150 spin_unlock_irqrestore(&pp->lock, flags); 1151 1152 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1153 pp->busy = 0; 1154 return -EFAULT; 1155 } 1156 1157 pp->cmd.cmd = hdr.cmd; 1158 pp->cmd.data_len = hdr.data_len; 1159 pp->cmd.reply_len = SMU_MAX_DATA; 1160 pp->cmd.data_buf = pp->buffer; 1161 pp->cmd.reply_buf = pp->buffer; 1162 pp->cmd.done = smu_user_cmd_done; 1163 pp->cmd.misc = pp; 1164 rc = smu_queue_cmd(&pp->cmd); 1165 if (rc < 0) 1166 return rc; 1167 return count; 1168 } 1169 1170 1171 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1172 char __user *buf, size_t count) 1173 { 1174 DECLARE_WAITQUEUE(wait, current); 1175 struct smu_user_reply_hdr hdr; 1176 unsigned long flags; 1177 int size, rc = 0; 1178 1179 if (!pp->busy) 1180 return 0; 1181 if (count < sizeof(struct smu_user_reply_hdr)) 1182 return -EOVERFLOW; 1183 spin_lock_irqsave(&pp->lock, flags); 1184 if (pp->cmd.status == 1) { 1185 if (file->f_flags & O_NONBLOCK) 1186 return -EAGAIN; 1187 add_wait_queue(&pp->wait, &wait); 1188 for (;;) { 1189 set_current_state(TASK_INTERRUPTIBLE); 1190 rc = 0; 1191 if (pp->cmd.status != 1) 1192 break; 1193 rc = -ERESTARTSYS; 1194 if (signal_pending(current)) 1195 break; 1196 spin_unlock_irqrestore(&pp->lock, flags); 1197 schedule(); 1198 spin_lock_irqsave(&pp->lock, flags); 1199 } 1200 set_current_state(TASK_RUNNING); 1201 remove_wait_queue(&pp->wait, &wait); 1202 } 1203 spin_unlock_irqrestore(&pp->lock, flags); 1204 if (rc) 1205 return rc; 1206 if (pp->cmd.status != 0) 1207 pp->cmd.reply_len = 0; 1208 size = sizeof(hdr) + pp->cmd.reply_len; 1209 if (count < size) 1210 size = count; 1211 rc = size; 1212 hdr.status = pp->cmd.status; 1213 hdr.reply_len = pp->cmd.reply_len; 1214 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1215 return -EFAULT; 1216 size -= sizeof(hdr); 1217 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1218 return -EFAULT; 1219 pp->busy = 0; 1220 1221 return rc; 1222 } 1223 1224 1225 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1226 char __user *buf, size_t count) 1227 { 1228 /* Not implemented */ 1229 msleep_interruptible(1000); 1230 return 0; 1231 } 1232 1233 1234 static ssize_t smu_read(struct file *file, char __user *buf, 1235 size_t count, loff_t *ppos) 1236 { 1237 struct smu_private *pp = file->private_data; 1238 1239 if (pp->mode == smu_file_commands) 1240 return smu_read_command(file, pp, buf, count); 1241 if (pp->mode == smu_file_events) 1242 return smu_read_events(file, pp, buf, count); 1243 1244 return -EBADFD; 1245 } 1246 1247 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1248 { 1249 struct smu_private *pp = file->private_data; 1250 unsigned int mask = 0; 1251 unsigned long flags; 1252 1253 if (pp == 0) 1254 return 0; 1255 1256 if (pp->mode == smu_file_commands) { 1257 poll_wait(file, &pp->wait, wait); 1258 1259 spin_lock_irqsave(&pp->lock, flags); 1260 if (pp->busy && pp->cmd.status != 1) 1261 mask |= POLLIN; 1262 spin_unlock_irqrestore(&pp->lock, flags); 1263 } if (pp->mode == smu_file_events) { 1264 /* Not yet implemented */ 1265 } 1266 return mask; 1267 } 1268 1269 static int smu_release(struct inode *inode, struct file *file) 1270 { 1271 struct smu_private *pp = file->private_data; 1272 unsigned long flags; 1273 unsigned int busy; 1274 1275 if (pp == 0) 1276 return 0; 1277 1278 file->private_data = NULL; 1279 1280 /* Mark file as closing to avoid races with new request */ 1281 spin_lock_irqsave(&pp->lock, flags); 1282 pp->mode = smu_file_closing; 1283 busy = pp->busy; 1284 1285 /* Wait for any pending request to complete */ 1286 if (busy && pp->cmd.status == 1) { 1287 DECLARE_WAITQUEUE(wait, current); 1288 1289 add_wait_queue(&pp->wait, &wait); 1290 for (;;) { 1291 set_current_state(TASK_UNINTERRUPTIBLE); 1292 if (pp->cmd.status != 1) 1293 break; 1294 spin_unlock_irqrestore(&pp->lock, flags); 1295 schedule(); 1296 spin_lock_irqsave(&pp->lock, flags); 1297 } 1298 set_current_state(TASK_RUNNING); 1299 remove_wait_queue(&pp->wait, &wait); 1300 } 1301 spin_unlock_irqrestore(&pp->lock, flags); 1302 1303 spin_lock_irqsave(&smu_clist_lock, flags); 1304 list_del(&pp->list); 1305 spin_unlock_irqrestore(&smu_clist_lock, flags); 1306 kfree(pp); 1307 1308 return 0; 1309 } 1310 1311 1312 static const struct file_operations smu_device_fops = { 1313 .llseek = no_llseek, 1314 .read = smu_read, 1315 .write = smu_write, 1316 .poll = smu_fpoll, 1317 .open = smu_open, 1318 .release = smu_release, 1319 }; 1320 1321 static struct miscdevice pmu_device = { 1322 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1323 }; 1324 1325 static int smu_device_init(void) 1326 { 1327 if (!smu) 1328 return -ENODEV; 1329 if (misc_register(&pmu_device) < 0) 1330 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1331 return 0; 1332 } 1333 device_initcall(smu_device_init); 1334