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_platform.h> 39 #include <linux/slab.h> 40 41 #include <asm/byteorder.h> 42 #include <asm/io.h> 43 #include <asm/prom.h> 44 #include <asm/machdep.h> 45 #include <asm/pmac_feature.h> 46 #include <asm/smu.h> 47 #include <asm/sections.h> 48 #include <asm/abs_addr.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: %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 platform_device* dev) 648 { 649 if (!smu) 650 return -ENODEV; 651 smu->of_dev = dev; 652 653 /* 654 * Ok, we are matched, now expose all i2c busses. We have to defer 655 * that unfortunately or it would deadlock inside the device model 656 */ 657 schedule_work(&smu_expose_childs_work); 658 659 return 0; 660 } 661 662 static const struct of_device_id smu_platform_match[] = 663 { 664 { 665 .type = "smu", 666 }, 667 {}, 668 }; 669 670 static struct platform_driver smu_of_platform_driver = 671 { 672 .driver = { 673 .name = "smu", 674 .owner = THIS_MODULE, 675 .of_match_table = smu_platform_match, 676 }, 677 .probe = smu_platform_probe, 678 }; 679 680 static int __init smu_init_sysfs(void) 681 { 682 /* 683 * For now, we don't power manage machines with an SMU chip, 684 * I'm a bit too far from figuring out how that works with those 685 * new chipsets, but that will come back and bite us 686 */ 687 platform_driver_register(&smu_of_platform_driver); 688 return 0; 689 } 690 691 device_initcall(smu_init_sysfs); 692 693 struct platform_device *smu_get_ofdev(void) 694 { 695 if (!smu) 696 return NULL; 697 return smu->of_dev; 698 } 699 700 EXPORT_SYMBOL_GPL(smu_get_ofdev); 701 702 /* 703 * i2c interface 704 */ 705 706 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 707 { 708 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 709 void *misc = cmd->misc; 710 unsigned long flags; 711 712 /* Check for read case */ 713 if (!fail && cmd->read) { 714 if (cmd->pdata[0] < 1) 715 fail = 1; 716 else 717 memcpy(cmd->info.data, &cmd->pdata[1], 718 cmd->info.datalen); 719 } 720 721 DPRINTK("SMU: completing, success: %d\n", !fail); 722 723 /* Update status and mark no pending i2c command with lock 724 * held so nobody comes in while we dequeue an eventual 725 * pending next i2c command 726 */ 727 spin_lock_irqsave(&smu->lock, flags); 728 smu->cmd_i2c_cur = NULL; 729 wmb(); 730 cmd->status = fail ? -EIO : 0; 731 732 /* Is there another i2c command waiting ? */ 733 if (!list_empty(&smu->cmd_i2c_list)) { 734 struct smu_i2c_cmd *newcmd; 735 736 /* Fetch it, new current, remove from list */ 737 newcmd = list_entry(smu->cmd_i2c_list.next, 738 struct smu_i2c_cmd, link); 739 smu->cmd_i2c_cur = newcmd; 740 list_del(&cmd->link); 741 742 /* Queue with low level smu */ 743 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 744 if (smu->cmd_cur == NULL) 745 smu_start_cmd(); 746 } 747 spin_unlock_irqrestore(&smu->lock, flags); 748 749 /* Call command completion handler if any */ 750 if (done) 751 done(cmd, misc); 752 753 } 754 755 756 static void smu_i2c_retry(unsigned long data) 757 { 758 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 759 760 DPRINTK("SMU: i2c failure, requeuing...\n"); 761 762 /* requeue command simply by resetting reply_len */ 763 cmd->pdata[0] = 0xff; 764 cmd->scmd.reply_len = sizeof(cmd->pdata); 765 smu_queue_cmd(&cmd->scmd); 766 } 767 768 769 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 770 { 771 struct smu_i2c_cmd *cmd = misc; 772 int fail = 0; 773 774 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 775 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 776 777 /* Check for possible status */ 778 if (scmd->status < 0) 779 fail = 1; 780 else if (cmd->read) { 781 if (cmd->stage == 0) 782 fail = cmd->pdata[0] != 0; 783 else 784 fail = cmd->pdata[0] >= 0x80; 785 } else { 786 fail = cmd->pdata[0] != 0; 787 } 788 789 /* Handle failures by requeuing command, after 5ms interval 790 */ 791 if (fail && --cmd->retries > 0) { 792 DPRINTK("SMU: i2c failure, starting timer...\n"); 793 BUG_ON(cmd != smu->cmd_i2c_cur); 794 if (!smu_irq_inited) { 795 mdelay(5); 796 smu_i2c_retry(0); 797 return; 798 } 799 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 800 return; 801 } 802 803 /* If failure or stage 1, command is complete */ 804 if (fail || cmd->stage != 0) { 805 smu_i2c_complete_command(cmd, fail); 806 return; 807 } 808 809 DPRINTK("SMU: going to stage 1\n"); 810 811 /* Ok, initial command complete, now poll status */ 812 scmd->reply_buf = cmd->pdata; 813 scmd->reply_len = sizeof(cmd->pdata); 814 scmd->data_buf = cmd->pdata; 815 scmd->data_len = 1; 816 cmd->pdata[0] = 0; 817 cmd->stage = 1; 818 cmd->retries = 20; 819 smu_queue_cmd(scmd); 820 } 821 822 823 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 824 { 825 unsigned long flags; 826 827 if (smu == NULL) 828 return -ENODEV; 829 830 /* Fill most fields of scmd */ 831 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 832 cmd->scmd.done = smu_i2c_low_completion; 833 cmd->scmd.misc = cmd; 834 cmd->scmd.reply_buf = cmd->pdata; 835 cmd->scmd.reply_len = sizeof(cmd->pdata); 836 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 837 cmd->scmd.status = 1; 838 cmd->stage = 0; 839 cmd->pdata[0] = 0xff; 840 cmd->retries = 20; 841 cmd->status = 1; 842 843 /* Check transfer type, sanitize some "info" fields 844 * based on transfer type and do more checking 845 */ 846 cmd->info.caddr = cmd->info.devaddr; 847 cmd->read = cmd->info.devaddr & 0x01; 848 switch(cmd->info.type) { 849 case SMU_I2C_TRANSFER_SIMPLE: 850 memset(&cmd->info.sublen, 0, 4); 851 break; 852 case SMU_I2C_TRANSFER_COMBINED: 853 cmd->info.devaddr &= 0xfe; 854 case SMU_I2C_TRANSFER_STDSUB: 855 if (cmd->info.sublen > 3) 856 return -EINVAL; 857 break; 858 default: 859 return -EINVAL; 860 } 861 862 /* Finish setting up command based on transfer direction 863 */ 864 if (cmd->read) { 865 if (cmd->info.datalen > SMU_I2C_READ_MAX) 866 return -EINVAL; 867 memset(cmd->info.data, 0xff, cmd->info.datalen); 868 cmd->scmd.data_len = 9; 869 } else { 870 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 871 return -EINVAL; 872 cmd->scmd.data_len = 9 + cmd->info.datalen; 873 } 874 875 DPRINTK("SMU: i2c enqueuing command\n"); 876 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 877 cmd->read ? "read" : "write", cmd->info.datalen, 878 cmd->info.bus, cmd->info.caddr, 879 cmd->info.subaddr[0], cmd->info.type); 880 881 882 /* Enqueue command in i2c list, and if empty, enqueue also in 883 * main command list 884 */ 885 spin_lock_irqsave(&smu->lock, flags); 886 if (smu->cmd_i2c_cur == NULL) { 887 smu->cmd_i2c_cur = cmd; 888 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 889 if (smu->cmd_cur == NULL) 890 smu_start_cmd(); 891 } else 892 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 893 spin_unlock_irqrestore(&smu->lock, flags); 894 895 return 0; 896 } 897 898 /* 899 * Handling of "partitions" 900 */ 901 902 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 903 { 904 DECLARE_COMPLETION_ONSTACK(comp); 905 unsigned int chunk; 906 struct smu_cmd cmd; 907 int rc; 908 u8 params[8]; 909 910 /* We currently use a chunk size of 0xe. We could check the 911 * SMU firmware version and use bigger sizes though 912 */ 913 chunk = 0xe; 914 915 while (len) { 916 unsigned int clen = min(len, chunk); 917 918 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 919 cmd.data_len = 7; 920 cmd.data_buf = params; 921 cmd.reply_len = chunk; 922 cmd.reply_buf = dest; 923 cmd.done = smu_done_complete; 924 cmd.misc = ∁ 925 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 926 params[1] = 0x4; 927 *((u32 *)¶ms[2]) = addr; 928 params[6] = clen; 929 930 rc = smu_queue_cmd(&cmd); 931 if (rc) 932 return rc; 933 wait_for_completion(&comp); 934 if (cmd.status != 0) 935 return rc; 936 if (cmd.reply_len != clen) { 937 printk(KERN_DEBUG "SMU: short read in " 938 "smu_read_datablock, got: %d, want: %d\n", 939 cmd.reply_len, clen); 940 return -EIO; 941 } 942 len -= clen; 943 addr += clen; 944 dest += clen; 945 } 946 return 0; 947 } 948 949 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 950 { 951 DECLARE_COMPLETION_ONSTACK(comp); 952 struct smu_simple_cmd cmd; 953 unsigned int addr, len, tlen; 954 struct smu_sdbp_header *hdr; 955 struct property *prop; 956 957 /* First query the partition info */ 958 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 959 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 960 smu_done_complete, &comp, 961 SMU_CMD_PARTITION_LATEST, id); 962 wait_for_completion(&comp); 963 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 964 cmd.cmd.status, cmd.cmd.reply_len); 965 966 /* Partition doesn't exist (or other error) */ 967 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 968 return NULL; 969 970 /* Fetch address and length from reply */ 971 addr = *((u16 *)cmd.buffer); 972 len = cmd.buffer[3] << 2; 973 /* Calucluate total length to allocate, including the 17 bytes 974 * for "sdb-partition-XX" that we append at the end of the buffer 975 */ 976 tlen = sizeof(struct property) + len + 18; 977 978 prop = kzalloc(tlen, GFP_KERNEL); 979 if (prop == NULL) 980 return NULL; 981 hdr = (struct smu_sdbp_header *)(prop + 1); 982 prop->name = ((char *)prop) + tlen - 18; 983 sprintf(prop->name, "sdb-partition-%02x", id); 984 prop->length = len; 985 prop->value = hdr; 986 prop->next = NULL; 987 988 /* Read the datablock */ 989 if (smu_read_datablock((u8 *)hdr, addr, len)) { 990 printk(KERN_DEBUG "SMU: datablock read failed while reading " 991 "partition %02x !\n", id); 992 goto failure; 993 } 994 995 /* Got it, check a few things and create the property */ 996 if (hdr->id != id) { 997 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 998 "%02x !\n", id, hdr->id); 999 goto failure; 1000 } 1001 if (prom_add_property(smu->of_node, prop)) { 1002 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 1003 "property !\n", id); 1004 goto failure; 1005 } 1006 1007 return hdr; 1008 failure: 1009 kfree(prop); 1010 return NULL; 1011 } 1012 1013 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 1014 * when interruptible is 1 1015 */ 1016 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 1017 unsigned int *size, int interruptible) 1018 { 1019 char pname[32]; 1020 const struct smu_sdbp_header *part; 1021 1022 if (!smu) 1023 return NULL; 1024 1025 sprintf(pname, "sdb-partition-%02x", id); 1026 1027 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 1028 1029 if (interruptible) { 1030 int rc; 1031 rc = mutex_lock_interruptible(&smu_part_access); 1032 if (rc) 1033 return ERR_PTR(rc); 1034 } else 1035 mutex_lock(&smu_part_access); 1036 1037 part = of_get_property(smu->of_node, pname, size); 1038 if (part == NULL) { 1039 DPRINTK("trying to extract from SMU ...\n"); 1040 part = smu_create_sdb_partition(id); 1041 if (part != NULL && size) 1042 *size = part->len << 2; 1043 } 1044 mutex_unlock(&smu_part_access); 1045 return part; 1046 } 1047 1048 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1049 { 1050 return __smu_get_sdb_partition(id, size, 0); 1051 } 1052 EXPORT_SYMBOL(smu_get_sdb_partition); 1053 1054 1055 /* 1056 * Userland driver interface 1057 */ 1058 1059 1060 static LIST_HEAD(smu_clist); 1061 static DEFINE_SPINLOCK(smu_clist_lock); 1062 1063 enum smu_file_mode { 1064 smu_file_commands, 1065 smu_file_events, 1066 smu_file_closing 1067 }; 1068 1069 struct smu_private 1070 { 1071 struct list_head list; 1072 enum smu_file_mode mode; 1073 int busy; 1074 struct smu_cmd cmd; 1075 spinlock_t lock; 1076 wait_queue_head_t wait; 1077 u8 buffer[SMU_MAX_DATA]; 1078 }; 1079 1080 1081 static int smu_open(struct inode *inode, struct file *file) 1082 { 1083 struct smu_private *pp; 1084 unsigned long flags; 1085 1086 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1087 if (pp == 0) 1088 return -ENOMEM; 1089 spin_lock_init(&pp->lock); 1090 pp->mode = smu_file_commands; 1091 init_waitqueue_head(&pp->wait); 1092 1093 mutex_lock(&smu_mutex); 1094 spin_lock_irqsave(&smu_clist_lock, flags); 1095 list_add(&pp->list, &smu_clist); 1096 spin_unlock_irqrestore(&smu_clist_lock, flags); 1097 file->private_data = pp; 1098 mutex_unlock(&smu_mutex); 1099 1100 return 0; 1101 } 1102 1103 1104 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1105 { 1106 struct smu_private *pp = misc; 1107 1108 wake_up_all(&pp->wait); 1109 } 1110 1111 1112 static ssize_t smu_write(struct file *file, const char __user *buf, 1113 size_t count, loff_t *ppos) 1114 { 1115 struct smu_private *pp = file->private_data; 1116 unsigned long flags; 1117 struct smu_user_cmd_hdr hdr; 1118 int rc = 0; 1119 1120 if (pp->busy) 1121 return -EBUSY; 1122 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1123 return -EFAULT; 1124 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1125 pp->mode = smu_file_events; 1126 return 0; 1127 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1128 const struct smu_sdbp_header *part; 1129 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1130 if (part == NULL) 1131 return -EINVAL; 1132 else if (IS_ERR(part)) 1133 return PTR_ERR(part); 1134 return 0; 1135 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1136 return -EINVAL; 1137 else if (pp->mode != smu_file_commands) 1138 return -EBADFD; 1139 else if (hdr.data_len > SMU_MAX_DATA) 1140 return -EINVAL; 1141 1142 spin_lock_irqsave(&pp->lock, flags); 1143 if (pp->busy) { 1144 spin_unlock_irqrestore(&pp->lock, flags); 1145 return -EBUSY; 1146 } 1147 pp->busy = 1; 1148 pp->cmd.status = 1; 1149 spin_unlock_irqrestore(&pp->lock, flags); 1150 1151 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1152 pp->busy = 0; 1153 return -EFAULT; 1154 } 1155 1156 pp->cmd.cmd = hdr.cmd; 1157 pp->cmd.data_len = hdr.data_len; 1158 pp->cmd.reply_len = SMU_MAX_DATA; 1159 pp->cmd.data_buf = pp->buffer; 1160 pp->cmd.reply_buf = pp->buffer; 1161 pp->cmd.done = smu_user_cmd_done; 1162 pp->cmd.misc = pp; 1163 rc = smu_queue_cmd(&pp->cmd); 1164 if (rc < 0) 1165 return rc; 1166 return count; 1167 } 1168 1169 1170 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1171 char __user *buf, size_t count) 1172 { 1173 DECLARE_WAITQUEUE(wait, current); 1174 struct smu_user_reply_hdr hdr; 1175 unsigned long flags; 1176 int size, rc = 0; 1177 1178 if (!pp->busy) 1179 return 0; 1180 if (count < sizeof(struct smu_user_reply_hdr)) 1181 return -EOVERFLOW; 1182 spin_lock_irqsave(&pp->lock, flags); 1183 if (pp->cmd.status == 1) { 1184 if (file->f_flags & O_NONBLOCK) { 1185 spin_unlock_irqrestore(&pp->lock, flags); 1186 return -EAGAIN; 1187 } 1188 add_wait_queue(&pp->wait, &wait); 1189 for (;;) { 1190 set_current_state(TASK_INTERRUPTIBLE); 1191 rc = 0; 1192 if (pp->cmd.status != 1) 1193 break; 1194 rc = -ERESTARTSYS; 1195 if (signal_pending(current)) 1196 break; 1197 spin_unlock_irqrestore(&pp->lock, flags); 1198 schedule(); 1199 spin_lock_irqsave(&pp->lock, flags); 1200 } 1201 set_current_state(TASK_RUNNING); 1202 remove_wait_queue(&pp->wait, &wait); 1203 } 1204 spin_unlock_irqrestore(&pp->lock, flags); 1205 if (rc) 1206 return rc; 1207 if (pp->cmd.status != 0) 1208 pp->cmd.reply_len = 0; 1209 size = sizeof(hdr) + pp->cmd.reply_len; 1210 if (count < size) 1211 size = count; 1212 rc = size; 1213 hdr.status = pp->cmd.status; 1214 hdr.reply_len = pp->cmd.reply_len; 1215 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1216 return -EFAULT; 1217 size -= sizeof(hdr); 1218 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1219 return -EFAULT; 1220 pp->busy = 0; 1221 1222 return rc; 1223 } 1224 1225 1226 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1227 char __user *buf, size_t count) 1228 { 1229 /* Not implemented */ 1230 msleep_interruptible(1000); 1231 return 0; 1232 } 1233 1234 1235 static ssize_t smu_read(struct file *file, char __user *buf, 1236 size_t count, loff_t *ppos) 1237 { 1238 struct smu_private *pp = file->private_data; 1239 1240 if (pp->mode == smu_file_commands) 1241 return smu_read_command(file, pp, buf, count); 1242 if (pp->mode == smu_file_events) 1243 return smu_read_events(file, pp, buf, count); 1244 1245 return -EBADFD; 1246 } 1247 1248 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1249 { 1250 struct smu_private *pp = file->private_data; 1251 unsigned int mask = 0; 1252 unsigned long flags; 1253 1254 if (pp == 0) 1255 return 0; 1256 1257 if (pp->mode == smu_file_commands) { 1258 poll_wait(file, &pp->wait, wait); 1259 1260 spin_lock_irqsave(&pp->lock, flags); 1261 if (pp->busy && pp->cmd.status != 1) 1262 mask |= POLLIN; 1263 spin_unlock_irqrestore(&pp->lock, flags); 1264 } if (pp->mode == smu_file_events) { 1265 /* Not yet implemented */ 1266 } 1267 return mask; 1268 } 1269 1270 static int smu_release(struct inode *inode, struct file *file) 1271 { 1272 struct smu_private *pp = file->private_data; 1273 unsigned long flags; 1274 unsigned int busy; 1275 1276 if (pp == 0) 1277 return 0; 1278 1279 file->private_data = NULL; 1280 1281 /* Mark file as closing to avoid races with new request */ 1282 spin_lock_irqsave(&pp->lock, flags); 1283 pp->mode = smu_file_closing; 1284 busy = pp->busy; 1285 1286 /* Wait for any pending request to complete */ 1287 if (busy && pp->cmd.status == 1) { 1288 DECLARE_WAITQUEUE(wait, current); 1289 1290 add_wait_queue(&pp->wait, &wait); 1291 for (;;) { 1292 set_current_state(TASK_UNINTERRUPTIBLE); 1293 if (pp->cmd.status != 1) 1294 break; 1295 spin_unlock_irqrestore(&pp->lock, flags); 1296 schedule(); 1297 spin_lock_irqsave(&pp->lock, flags); 1298 } 1299 set_current_state(TASK_RUNNING); 1300 remove_wait_queue(&pp->wait, &wait); 1301 } 1302 spin_unlock_irqrestore(&pp->lock, flags); 1303 1304 spin_lock_irqsave(&smu_clist_lock, flags); 1305 list_del(&pp->list); 1306 spin_unlock_irqrestore(&smu_clist_lock, flags); 1307 kfree(pp); 1308 1309 return 0; 1310 } 1311 1312 1313 static const struct file_operations smu_device_fops = { 1314 .llseek = no_llseek, 1315 .read = smu_read, 1316 .write = smu_write, 1317 .poll = smu_fpoll, 1318 .open = smu_open, 1319 .release = smu_release, 1320 }; 1321 1322 static struct miscdevice pmu_device = { 1323 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1324 }; 1325 1326 static int smu_device_init(void) 1327 { 1328 if (!smu) 1329 return -ENODEV; 1330 if (misc_register(&pmu_device) < 0) 1331 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1332 return 0; 1333 } 1334 device_initcall(smu_device_init); 1335