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/uaccess.h> 49 50 #define VERSION "0.7" 51 #define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp." 52 53 #undef DEBUG_SMU 54 55 #ifdef DEBUG_SMU 56 #define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0) 57 #else 58 #define DPRINTK(fmt, args...) do { } while (0) 59 #endif 60 61 /* 62 * This is the command buffer passed to the SMU hardware 63 */ 64 #define SMU_MAX_DATA 254 65 66 struct smu_cmd_buf { 67 u8 cmd; 68 u8 length; 69 u8 data[SMU_MAX_DATA]; 70 }; 71 72 struct smu_device { 73 spinlock_t lock; 74 struct device_node *of_node; 75 struct platform_device *of_dev; 76 int doorbell; /* doorbell gpio */ 77 u32 __iomem *db_buf; /* doorbell buffer */ 78 struct device_node *db_node; 79 unsigned int db_irq; 80 int msg; 81 struct device_node *msg_node; 82 unsigned int msg_irq; 83 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ 84 u32 cmd_buf_abs; /* command buffer absolute */ 85 struct list_head cmd_list; 86 struct smu_cmd *cmd_cur; /* pending command */ 87 int broken_nap; 88 struct list_head cmd_i2c_list; 89 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 90 struct timer_list i2c_timer; 91 }; 92 93 /* 94 * I don't think there will ever be more than one SMU, so 95 * for now, just hard code that 96 */ 97 static DEFINE_MUTEX(smu_mutex); 98 static struct smu_device *smu; 99 static DEFINE_MUTEX(smu_part_access); 100 static int smu_irq_inited; 101 102 static void smu_i2c_retry(unsigned long data); 103 104 /* 105 * SMU driver low level stuff 106 */ 107 108 static void smu_start_cmd(void) 109 { 110 unsigned long faddr, fend; 111 struct smu_cmd *cmd; 112 113 if (list_empty(&smu->cmd_list)) 114 return; 115 116 /* Fetch first command in queue */ 117 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 118 smu->cmd_cur = cmd; 119 list_del(&cmd->link); 120 121 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 122 cmd->data_len); 123 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 124 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 125 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 126 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 127 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 128 129 /* Fill the SMU command buffer */ 130 smu->cmd_buf->cmd = cmd->cmd; 131 smu->cmd_buf->length = cmd->data_len; 132 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 133 134 /* Flush command and data to RAM */ 135 faddr = (unsigned long)smu->cmd_buf; 136 fend = faddr + smu->cmd_buf->length + 2; 137 flush_inval_dcache_range(faddr, fend); 138 139 140 /* We also disable NAP mode for the duration of the command 141 * on U3 based machines. 142 * This is slightly racy as it can be written back to 1 by a sysctl 143 * but that never happens in practice. There seem to be an issue with 144 * U3 based machines such as the iMac G5 where napping for the 145 * whole duration of the command prevents the SMU from fetching it 146 * from memory. This might be related to the strange i2c based 147 * mechanism the SMU uses to access memory. 148 */ 149 if (smu->broken_nap) 150 powersave_nap = 0; 151 152 /* This isn't exactly a DMA mapping here, I suspect 153 * the SMU is actually communicating with us via i2c to the 154 * northbridge or the CPU to access RAM. 155 */ 156 writel(smu->cmd_buf_abs, smu->db_buf); 157 158 /* Ring the SMU doorbell */ 159 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 160 } 161 162 163 static irqreturn_t smu_db_intr(int irq, void *arg) 164 { 165 unsigned long flags; 166 struct smu_cmd *cmd; 167 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 168 void *misc = NULL; 169 u8 gpio; 170 int rc = 0; 171 172 /* SMU completed the command, well, we hope, let's make sure 173 * of it 174 */ 175 spin_lock_irqsave(&smu->lock, flags); 176 177 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 178 if ((gpio & 7) != 7) { 179 spin_unlock_irqrestore(&smu->lock, flags); 180 return IRQ_HANDLED; 181 } 182 183 cmd = smu->cmd_cur; 184 smu->cmd_cur = NULL; 185 if (cmd == NULL) 186 goto bail; 187 188 if (rc == 0) { 189 unsigned long faddr; 190 int reply_len; 191 u8 ack; 192 193 /* CPU might have brought back the cache line, so we need 194 * to flush again before peeking at the SMU response. We 195 * flush the entire buffer for now as we haven't read the 196 * reply length (it's only 2 cache lines anyway) 197 */ 198 faddr = (unsigned long)smu->cmd_buf; 199 flush_inval_dcache_range(faddr, faddr + 256); 200 201 /* Now check ack */ 202 ack = (~cmd->cmd) & 0xff; 203 if (ack != smu->cmd_buf->cmd) { 204 DPRINTK("SMU: incorrect ack, want %x got %x\n", 205 ack, smu->cmd_buf->cmd); 206 rc = -EIO; 207 } 208 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 209 DPRINTK("SMU: reply len: %d\n", reply_len); 210 if (reply_len > cmd->reply_len) { 211 printk(KERN_WARNING "SMU: reply buffer too small," 212 "got %d bytes for a %d bytes buffer\n", 213 reply_len, cmd->reply_len); 214 reply_len = cmd->reply_len; 215 } 216 cmd->reply_len = reply_len; 217 if (cmd->reply_buf && reply_len) 218 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 219 } 220 221 /* Now complete the command. Write status last in order as we lost 222 * ownership of the command structure as soon as it's no longer -1 223 */ 224 done = cmd->done; 225 misc = cmd->misc; 226 mb(); 227 cmd->status = rc; 228 229 /* Re-enable NAP mode */ 230 if (smu->broken_nap) 231 powersave_nap = 1; 232 bail: 233 /* Start next command if any */ 234 smu_start_cmd(); 235 spin_unlock_irqrestore(&smu->lock, flags); 236 237 /* Call command completion handler if any */ 238 if (done) 239 done(cmd, misc); 240 241 /* It's an edge interrupt, nothing to do */ 242 return IRQ_HANDLED; 243 } 244 245 246 static irqreturn_t smu_msg_intr(int irq, void *arg) 247 { 248 /* I don't quite know what to do with this one, we seem to never 249 * receive it, so I suspect we have to arm it someway in the SMU 250 * to start getting events that way. 251 */ 252 253 printk(KERN_INFO "SMU: message interrupt !\n"); 254 255 /* It's an edge interrupt, nothing to do */ 256 return IRQ_HANDLED; 257 } 258 259 260 /* 261 * Queued command management. 262 * 263 */ 264 265 int smu_queue_cmd(struct smu_cmd *cmd) 266 { 267 unsigned long flags; 268 269 if (smu == NULL) 270 return -ENODEV; 271 if (cmd->data_len > SMU_MAX_DATA || 272 cmd->reply_len > SMU_MAX_DATA) 273 return -EINVAL; 274 275 cmd->status = 1; 276 spin_lock_irqsave(&smu->lock, flags); 277 list_add_tail(&cmd->link, &smu->cmd_list); 278 if (smu->cmd_cur == NULL) 279 smu_start_cmd(); 280 spin_unlock_irqrestore(&smu->lock, flags); 281 282 /* Workaround for early calls when irq isn't available */ 283 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 284 smu_spinwait_cmd(cmd); 285 286 return 0; 287 } 288 EXPORT_SYMBOL(smu_queue_cmd); 289 290 291 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 292 unsigned int data_len, 293 void (*done)(struct smu_cmd *cmd, void *misc), 294 void *misc, ...) 295 { 296 struct smu_cmd *cmd = &scmd->cmd; 297 va_list list; 298 int i; 299 300 if (data_len > sizeof(scmd->buffer)) 301 return -EINVAL; 302 303 memset(scmd, 0, sizeof(*scmd)); 304 cmd->cmd = command; 305 cmd->data_len = data_len; 306 cmd->data_buf = scmd->buffer; 307 cmd->reply_len = sizeof(scmd->buffer); 308 cmd->reply_buf = scmd->buffer; 309 cmd->done = done; 310 cmd->misc = misc; 311 312 va_start(list, misc); 313 for (i = 0; i < data_len; ++i) 314 scmd->buffer[i] = (u8)va_arg(list, int); 315 va_end(list); 316 317 return smu_queue_cmd(cmd); 318 } 319 EXPORT_SYMBOL(smu_queue_simple); 320 321 322 void smu_poll(void) 323 { 324 u8 gpio; 325 326 if (smu == NULL) 327 return; 328 329 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 330 if ((gpio & 7) == 7) 331 smu_db_intr(smu->db_irq, smu); 332 } 333 EXPORT_SYMBOL(smu_poll); 334 335 336 void smu_done_complete(struct smu_cmd *cmd, void *misc) 337 { 338 struct completion *comp = misc; 339 340 complete(comp); 341 } 342 EXPORT_SYMBOL(smu_done_complete); 343 344 345 void smu_spinwait_cmd(struct smu_cmd *cmd) 346 { 347 while(cmd->status == 1) 348 smu_poll(); 349 } 350 EXPORT_SYMBOL(smu_spinwait_cmd); 351 352 353 /* RTC low level commands */ 354 static inline int bcd2hex (int n) 355 { 356 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 357 } 358 359 360 static inline int hex2bcd (int n) 361 { 362 return ((n / 10) << 4) + (n % 10); 363 } 364 365 366 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 367 struct rtc_time *time) 368 { 369 cmd_buf->cmd = 0x8e; 370 cmd_buf->length = 8; 371 cmd_buf->data[0] = 0x80; 372 cmd_buf->data[1] = hex2bcd(time->tm_sec); 373 cmd_buf->data[2] = hex2bcd(time->tm_min); 374 cmd_buf->data[3] = hex2bcd(time->tm_hour); 375 cmd_buf->data[4] = time->tm_wday; 376 cmd_buf->data[5] = hex2bcd(time->tm_mday); 377 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 378 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 379 } 380 381 382 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 383 { 384 struct smu_simple_cmd cmd; 385 int rc; 386 387 if (smu == NULL) 388 return -ENODEV; 389 390 memset(time, 0, sizeof(struct rtc_time)); 391 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 392 SMU_CMD_RTC_GET_DATETIME); 393 if (rc) 394 return rc; 395 smu_spinwait_simple(&cmd); 396 397 time->tm_sec = bcd2hex(cmd.buffer[0]); 398 time->tm_min = bcd2hex(cmd.buffer[1]); 399 time->tm_hour = bcd2hex(cmd.buffer[2]); 400 time->tm_wday = bcd2hex(cmd.buffer[3]); 401 time->tm_mday = bcd2hex(cmd.buffer[4]); 402 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 403 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 404 405 return 0; 406 } 407 408 409 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 410 { 411 struct smu_simple_cmd cmd; 412 int rc; 413 414 if (smu == NULL) 415 return -ENODEV; 416 417 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 418 SMU_CMD_RTC_SET_DATETIME, 419 hex2bcd(time->tm_sec), 420 hex2bcd(time->tm_min), 421 hex2bcd(time->tm_hour), 422 time->tm_wday, 423 hex2bcd(time->tm_mday), 424 hex2bcd(time->tm_mon) + 1, 425 hex2bcd(time->tm_year - 100)); 426 if (rc) 427 return rc; 428 smu_spinwait_simple(&cmd); 429 430 return 0; 431 } 432 433 434 void smu_shutdown(void) 435 { 436 struct smu_simple_cmd cmd; 437 438 if (smu == NULL) 439 return; 440 441 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 442 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 443 return; 444 smu_spinwait_simple(&cmd); 445 for (;;) 446 ; 447 } 448 449 450 void smu_restart(void) 451 { 452 struct smu_simple_cmd cmd; 453 454 if (smu == NULL) 455 return; 456 457 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 458 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 459 return; 460 smu_spinwait_simple(&cmd); 461 for (;;) 462 ; 463 } 464 465 466 int smu_present(void) 467 { 468 return smu != NULL; 469 } 470 EXPORT_SYMBOL(smu_present); 471 472 473 int __init smu_init (void) 474 { 475 struct device_node *np; 476 const u32 *data; 477 int ret = 0; 478 479 np = of_find_node_by_type(NULL, "smu"); 480 if (np == NULL) 481 return -ENODEV; 482 483 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR); 484 485 if (smu_cmdbuf_abs == 0) { 486 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 487 ret = -EINVAL; 488 goto fail_np; 489 } 490 491 smu = alloc_bootmem(sizeof(struct smu_device)); 492 493 spin_lock_init(&smu->lock); 494 INIT_LIST_HEAD(&smu->cmd_list); 495 INIT_LIST_HEAD(&smu->cmd_i2c_list); 496 smu->of_node = np; 497 smu->db_irq = NO_IRQ; 498 smu->msg_irq = NO_IRQ; 499 500 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 501 * 32 bits value safely 502 */ 503 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 504 smu->cmd_buf = __va(smu_cmdbuf_abs); 505 506 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell"); 507 if (smu->db_node == NULL) { 508 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 509 ret = -ENXIO; 510 goto fail_bootmem; 511 } 512 data = of_get_property(smu->db_node, "reg", NULL); 513 if (data == NULL) { 514 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 515 ret = -ENXIO; 516 goto fail_db_node; 517 } 518 519 /* Current setup has one doorbell GPIO that does both doorbell 520 * and ack. GPIOs are at 0x50, best would be to find that out 521 * in the device-tree though. 522 */ 523 smu->doorbell = *data; 524 if (smu->doorbell < 0x50) 525 smu->doorbell += 0x50; 526 527 /* Now look for the smu-interrupt GPIO */ 528 do { 529 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt"); 530 if (smu->msg_node == NULL) 531 break; 532 data = of_get_property(smu->msg_node, "reg", NULL); 533 if (data == NULL) { 534 of_node_put(smu->msg_node); 535 smu->msg_node = NULL; 536 break; 537 } 538 smu->msg = *data; 539 if (smu->msg < 0x50) 540 smu->msg += 0x50; 541 } while(0); 542 543 /* Doorbell buffer is currently hard-coded, I didn't find a proper 544 * device-tree entry giving the address. Best would probably to use 545 * an offset for K2 base though, but let's do it that way for now. 546 */ 547 smu->db_buf = ioremap(0x8000860c, 0x1000); 548 if (smu->db_buf == NULL) { 549 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 550 ret = -ENXIO; 551 goto fail_msg_node; 552 } 553 554 /* U3 has an issue with NAP mode when issuing SMU commands */ 555 smu->broken_nap = pmac_get_uninorth_variant() < 4; 556 if (smu->broken_nap) 557 printk(KERN_INFO "SMU: using NAP mode workaround\n"); 558 559 sys_ctrler = SYS_CTRLER_SMU; 560 return 0; 561 562 fail_msg_node: 563 if (smu->msg_node) 564 of_node_put(smu->msg_node); 565 fail_db_node: 566 of_node_put(smu->db_node); 567 fail_bootmem: 568 free_bootmem((unsigned long)smu, sizeof(struct smu_device)); 569 smu = NULL; 570 fail_np: 571 of_node_put(np); 572 return ret; 573 } 574 575 576 static int smu_late_init(void) 577 { 578 if (!smu) 579 return 0; 580 581 init_timer(&smu->i2c_timer); 582 smu->i2c_timer.function = smu_i2c_retry; 583 smu->i2c_timer.data = (unsigned long)smu; 584 585 if (smu->db_node) { 586 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); 587 if (smu->db_irq == NO_IRQ) 588 printk(KERN_ERR "smu: failed to map irq for node %s\n", 589 smu->db_node->full_name); 590 } 591 if (smu->msg_node) { 592 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); 593 if (smu->msg_irq == NO_IRQ) 594 printk(KERN_ERR "smu: failed to map irq for node %s\n", 595 smu->msg_node->full_name); 596 } 597 598 /* 599 * Try to request the interrupts 600 */ 601 602 if (smu->db_irq != NO_IRQ) { 603 if (request_irq(smu->db_irq, smu_db_intr, 604 IRQF_SHARED, "SMU doorbell", smu) < 0) { 605 printk(KERN_WARNING "SMU: can't " 606 "request interrupt %d\n", 607 smu->db_irq); 608 smu->db_irq = NO_IRQ; 609 } 610 } 611 612 if (smu->msg_irq != NO_IRQ) { 613 if (request_irq(smu->msg_irq, smu_msg_intr, 614 IRQF_SHARED, "SMU message", smu) < 0) { 615 printk(KERN_WARNING "SMU: can't " 616 "request interrupt %d\n", 617 smu->msg_irq); 618 smu->msg_irq = NO_IRQ; 619 } 620 } 621 622 smu_irq_inited = 1; 623 return 0; 624 } 625 /* This has to be before arch_initcall as the low i2c stuff relies on the 626 * above having been done before we reach arch_initcalls 627 */ 628 core_initcall(smu_late_init); 629 630 /* 631 * sysfs visibility 632 */ 633 634 static void smu_expose_childs(struct work_struct *unused) 635 { 636 struct device_node *np; 637 638 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 639 if (of_device_is_compatible(np, "smu-sensors")) 640 of_platform_device_create(np, "smu-sensors", 641 &smu->of_dev->dev); 642 } 643 644 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 645 646 static int smu_platform_probe(struct platform_device* dev) 647 { 648 if (!smu) 649 return -ENODEV; 650 smu->of_dev = dev; 651 652 /* 653 * Ok, we are matched, now expose all i2c busses. We have to defer 654 * that unfortunately or it would deadlock inside the device model 655 */ 656 schedule_work(&smu_expose_childs_work); 657 658 return 0; 659 } 660 661 static const struct of_device_id smu_platform_match[] = 662 { 663 { 664 .type = "smu", 665 }, 666 {}, 667 }; 668 669 static struct platform_driver smu_of_platform_driver = 670 { 671 .driver = { 672 .name = "smu", 673 .owner = THIS_MODULE, 674 .of_match_table = smu_platform_match, 675 }, 676 .probe = smu_platform_probe, 677 }; 678 679 static int __init smu_init_sysfs(void) 680 { 681 /* 682 * For now, we don't power manage machines with an SMU chip, 683 * I'm a bit too far from figuring out how that works with those 684 * new chipsets, but that will come back and bite us 685 */ 686 platform_driver_register(&smu_of_platform_driver); 687 return 0; 688 } 689 690 device_initcall(smu_init_sysfs); 691 692 struct platform_device *smu_get_ofdev(void) 693 { 694 if (!smu) 695 return NULL; 696 return smu->of_dev; 697 } 698 699 EXPORT_SYMBOL_GPL(smu_get_ofdev); 700 701 /* 702 * i2c interface 703 */ 704 705 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 706 { 707 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 708 void *misc = cmd->misc; 709 unsigned long flags; 710 711 /* Check for read case */ 712 if (!fail && cmd->read) { 713 if (cmd->pdata[0] < 1) 714 fail = 1; 715 else 716 memcpy(cmd->info.data, &cmd->pdata[1], 717 cmd->info.datalen); 718 } 719 720 DPRINTK("SMU: completing, success: %d\n", !fail); 721 722 /* Update status and mark no pending i2c command with lock 723 * held so nobody comes in while we dequeue an eventual 724 * pending next i2c command 725 */ 726 spin_lock_irqsave(&smu->lock, flags); 727 smu->cmd_i2c_cur = NULL; 728 wmb(); 729 cmd->status = fail ? -EIO : 0; 730 731 /* Is there another i2c command waiting ? */ 732 if (!list_empty(&smu->cmd_i2c_list)) { 733 struct smu_i2c_cmd *newcmd; 734 735 /* Fetch it, new current, remove from list */ 736 newcmd = list_entry(smu->cmd_i2c_list.next, 737 struct smu_i2c_cmd, link); 738 smu->cmd_i2c_cur = newcmd; 739 list_del(&cmd->link); 740 741 /* Queue with low level smu */ 742 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 743 if (smu->cmd_cur == NULL) 744 smu_start_cmd(); 745 } 746 spin_unlock_irqrestore(&smu->lock, flags); 747 748 /* Call command completion handler if any */ 749 if (done) 750 done(cmd, misc); 751 752 } 753 754 755 static void smu_i2c_retry(unsigned long data) 756 { 757 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 758 759 DPRINTK("SMU: i2c failure, requeuing...\n"); 760 761 /* requeue command simply by resetting reply_len */ 762 cmd->pdata[0] = 0xff; 763 cmd->scmd.reply_len = sizeof(cmd->pdata); 764 smu_queue_cmd(&cmd->scmd); 765 } 766 767 768 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 769 { 770 struct smu_i2c_cmd *cmd = misc; 771 int fail = 0; 772 773 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 774 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 775 776 /* Check for possible status */ 777 if (scmd->status < 0) 778 fail = 1; 779 else if (cmd->read) { 780 if (cmd->stage == 0) 781 fail = cmd->pdata[0] != 0; 782 else 783 fail = cmd->pdata[0] >= 0x80; 784 } else { 785 fail = cmd->pdata[0] != 0; 786 } 787 788 /* Handle failures by requeuing command, after 5ms interval 789 */ 790 if (fail && --cmd->retries > 0) { 791 DPRINTK("SMU: i2c failure, starting timer...\n"); 792 BUG_ON(cmd != smu->cmd_i2c_cur); 793 if (!smu_irq_inited) { 794 mdelay(5); 795 smu_i2c_retry(0); 796 return; 797 } 798 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 799 return; 800 } 801 802 /* If failure or stage 1, command is complete */ 803 if (fail || cmd->stage != 0) { 804 smu_i2c_complete_command(cmd, fail); 805 return; 806 } 807 808 DPRINTK("SMU: going to stage 1\n"); 809 810 /* Ok, initial command complete, now poll status */ 811 scmd->reply_buf = cmd->pdata; 812 scmd->reply_len = sizeof(cmd->pdata); 813 scmd->data_buf = cmd->pdata; 814 scmd->data_len = 1; 815 cmd->pdata[0] = 0; 816 cmd->stage = 1; 817 cmd->retries = 20; 818 smu_queue_cmd(scmd); 819 } 820 821 822 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 823 { 824 unsigned long flags; 825 826 if (smu == NULL) 827 return -ENODEV; 828 829 /* Fill most fields of scmd */ 830 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 831 cmd->scmd.done = smu_i2c_low_completion; 832 cmd->scmd.misc = cmd; 833 cmd->scmd.reply_buf = cmd->pdata; 834 cmd->scmd.reply_len = sizeof(cmd->pdata); 835 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 836 cmd->scmd.status = 1; 837 cmd->stage = 0; 838 cmd->pdata[0] = 0xff; 839 cmd->retries = 20; 840 cmd->status = 1; 841 842 /* Check transfer type, sanitize some "info" fields 843 * based on transfer type and do more checking 844 */ 845 cmd->info.caddr = cmd->info.devaddr; 846 cmd->read = cmd->info.devaddr & 0x01; 847 switch(cmd->info.type) { 848 case SMU_I2C_TRANSFER_SIMPLE: 849 memset(&cmd->info.sublen, 0, 4); 850 break; 851 case SMU_I2C_TRANSFER_COMBINED: 852 cmd->info.devaddr &= 0xfe; 853 case SMU_I2C_TRANSFER_STDSUB: 854 if (cmd->info.sublen > 3) 855 return -EINVAL; 856 break; 857 default: 858 return -EINVAL; 859 } 860 861 /* Finish setting up command based on transfer direction 862 */ 863 if (cmd->read) { 864 if (cmd->info.datalen > SMU_I2C_READ_MAX) 865 return -EINVAL; 866 memset(cmd->info.data, 0xff, cmd->info.datalen); 867 cmd->scmd.data_len = 9; 868 } else { 869 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 870 return -EINVAL; 871 cmd->scmd.data_len = 9 + cmd->info.datalen; 872 } 873 874 DPRINTK("SMU: i2c enqueuing command\n"); 875 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 876 cmd->read ? "read" : "write", cmd->info.datalen, 877 cmd->info.bus, cmd->info.caddr, 878 cmd->info.subaddr[0], cmd->info.type); 879 880 881 /* Enqueue command in i2c list, and if empty, enqueue also in 882 * main command list 883 */ 884 spin_lock_irqsave(&smu->lock, flags); 885 if (smu->cmd_i2c_cur == NULL) { 886 smu->cmd_i2c_cur = cmd; 887 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 888 if (smu->cmd_cur == NULL) 889 smu_start_cmd(); 890 } else 891 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 892 spin_unlock_irqrestore(&smu->lock, flags); 893 894 return 0; 895 } 896 897 /* 898 * Handling of "partitions" 899 */ 900 901 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 902 { 903 DECLARE_COMPLETION_ONSTACK(comp); 904 unsigned int chunk; 905 struct smu_cmd cmd; 906 int rc; 907 u8 params[8]; 908 909 /* We currently use a chunk size of 0xe. We could check the 910 * SMU firmware version and use bigger sizes though 911 */ 912 chunk = 0xe; 913 914 while (len) { 915 unsigned int clen = min(len, chunk); 916 917 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 918 cmd.data_len = 7; 919 cmd.data_buf = params; 920 cmd.reply_len = chunk; 921 cmd.reply_buf = dest; 922 cmd.done = smu_done_complete; 923 cmd.misc = ∁ 924 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 925 params[1] = 0x4; 926 *((u32 *)¶ms[2]) = addr; 927 params[6] = clen; 928 929 rc = smu_queue_cmd(&cmd); 930 if (rc) 931 return rc; 932 wait_for_completion(&comp); 933 if (cmd.status != 0) 934 return rc; 935 if (cmd.reply_len != clen) { 936 printk(KERN_DEBUG "SMU: short read in " 937 "smu_read_datablock, got: %d, want: %d\n", 938 cmd.reply_len, clen); 939 return -EIO; 940 } 941 len -= clen; 942 addr += clen; 943 dest += clen; 944 } 945 return 0; 946 } 947 948 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 949 { 950 DECLARE_COMPLETION_ONSTACK(comp); 951 struct smu_simple_cmd cmd; 952 unsigned int addr, len, tlen; 953 struct smu_sdbp_header *hdr; 954 struct property *prop; 955 956 /* First query the partition info */ 957 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 958 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 959 smu_done_complete, &comp, 960 SMU_CMD_PARTITION_LATEST, id); 961 wait_for_completion(&comp); 962 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 963 cmd.cmd.status, cmd.cmd.reply_len); 964 965 /* Partition doesn't exist (or other error) */ 966 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 967 return NULL; 968 969 /* Fetch address and length from reply */ 970 addr = *((u16 *)cmd.buffer); 971 len = cmd.buffer[3] << 2; 972 /* Calucluate total length to allocate, including the 17 bytes 973 * for "sdb-partition-XX" that we append at the end of the buffer 974 */ 975 tlen = sizeof(struct property) + len + 18; 976 977 prop = kzalloc(tlen, GFP_KERNEL); 978 if (prop == NULL) 979 return NULL; 980 hdr = (struct smu_sdbp_header *)(prop + 1); 981 prop->name = ((char *)prop) + tlen - 18; 982 sprintf(prop->name, "sdb-partition-%02x", id); 983 prop->length = len; 984 prop->value = hdr; 985 prop->next = NULL; 986 987 /* Read the datablock */ 988 if (smu_read_datablock((u8 *)hdr, addr, len)) { 989 printk(KERN_DEBUG "SMU: datablock read failed while reading " 990 "partition %02x !\n", id); 991 goto failure; 992 } 993 994 /* Got it, check a few things and create the property */ 995 if (hdr->id != id) { 996 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 997 "%02x !\n", id, hdr->id); 998 goto failure; 999 } 1000 if (prom_add_property(smu->of_node, prop)) { 1001 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 1002 "property !\n", id); 1003 goto failure; 1004 } 1005 1006 return hdr; 1007 failure: 1008 kfree(prop); 1009 return NULL; 1010 } 1011 1012 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 1013 * when interruptible is 1 1014 */ 1015 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 1016 unsigned int *size, int interruptible) 1017 { 1018 char pname[32]; 1019 const struct smu_sdbp_header *part; 1020 1021 if (!smu) 1022 return NULL; 1023 1024 sprintf(pname, "sdb-partition-%02x", id); 1025 1026 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 1027 1028 if (interruptible) { 1029 int rc; 1030 rc = mutex_lock_interruptible(&smu_part_access); 1031 if (rc) 1032 return ERR_PTR(rc); 1033 } else 1034 mutex_lock(&smu_part_access); 1035 1036 part = of_get_property(smu->of_node, pname, size); 1037 if (part == NULL) { 1038 DPRINTK("trying to extract from SMU ...\n"); 1039 part = smu_create_sdb_partition(id); 1040 if (part != NULL && size) 1041 *size = part->len << 2; 1042 } 1043 mutex_unlock(&smu_part_access); 1044 return part; 1045 } 1046 1047 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1048 { 1049 return __smu_get_sdb_partition(id, size, 0); 1050 } 1051 EXPORT_SYMBOL(smu_get_sdb_partition); 1052 1053 1054 /* 1055 * Userland driver interface 1056 */ 1057 1058 1059 static LIST_HEAD(smu_clist); 1060 static DEFINE_SPINLOCK(smu_clist_lock); 1061 1062 enum smu_file_mode { 1063 smu_file_commands, 1064 smu_file_events, 1065 smu_file_closing 1066 }; 1067 1068 struct smu_private 1069 { 1070 struct list_head list; 1071 enum smu_file_mode mode; 1072 int busy; 1073 struct smu_cmd cmd; 1074 spinlock_t lock; 1075 wait_queue_head_t wait; 1076 u8 buffer[SMU_MAX_DATA]; 1077 }; 1078 1079 1080 static int smu_open(struct inode *inode, struct file *file) 1081 { 1082 struct smu_private *pp; 1083 unsigned long flags; 1084 1085 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1086 if (pp == 0) 1087 return -ENOMEM; 1088 spin_lock_init(&pp->lock); 1089 pp->mode = smu_file_commands; 1090 init_waitqueue_head(&pp->wait); 1091 1092 mutex_lock(&smu_mutex); 1093 spin_lock_irqsave(&smu_clist_lock, flags); 1094 list_add(&pp->list, &smu_clist); 1095 spin_unlock_irqrestore(&smu_clist_lock, flags); 1096 file->private_data = pp; 1097 mutex_unlock(&smu_mutex); 1098 1099 return 0; 1100 } 1101 1102 1103 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1104 { 1105 struct smu_private *pp = misc; 1106 1107 wake_up_all(&pp->wait); 1108 } 1109 1110 1111 static ssize_t smu_write(struct file *file, const char __user *buf, 1112 size_t count, loff_t *ppos) 1113 { 1114 struct smu_private *pp = file->private_data; 1115 unsigned long flags; 1116 struct smu_user_cmd_hdr hdr; 1117 int rc = 0; 1118 1119 if (pp->busy) 1120 return -EBUSY; 1121 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1122 return -EFAULT; 1123 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1124 pp->mode = smu_file_events; 1125 return 0; 1126 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1127 const struct smu_sdbp_header *part; 1128 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1129 if (part == NULL) 1130 return -EINVAL; 1131 else if (IS_ERR(part)) 1132 return PTR_ERR(part); 1133 return 0; 1134 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1135 return -EINVAL; 1136 else if (pp->mode != smu_file_commands) 1137 return -EBADFD; 1138 else if (hdr.data_len > SMU_MAX_DATA) 1139 return -EINVAL; 1140 1141 spin_lock_irqsave(&pp->lock, flags); 1142 if (pp->busy) { 1143 spin_unlock_irqrestore(&pp->lock, flags); 1144 return -EBUSY; 1145 } 1146 pp->busy = 1; 1147 pp->cmd.status = 1; 1148 spin_unlock_irqrestore(&pp->lock, flags); 1149 1150 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1151 pp->busy = 0; 1152 return -EFAULT; 1153 } 1154 1155 pp->cmd.cmd = hdr.cmd; 1156 pp->cmd.data_len = hdr.data_len; 1157 pp->cmd.reply_len = SMU_MAX_DATA; 1158 pp->cmd.data_buf = pp->buffer; 1159 pp->cmd.reply_buf = pp->buffer; 1160 pp->cmd.done = smu_user_cmd_done; 1161 pp->cmd.misc = pp; 1162 rc = smu_queue_cmd(&pp->cmd); 1163 if (rc < 0) 1164 return rc; 1165 return count; 1166 } 1167 1168 1169 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1170 char __user *buf, size_t count) 1171 { 1172 DECLARE_WAITQUEUE(wait, current); 1173 struct smu_user_reply_hdr hdr; 1174 unsigned long flags; 1175 int size, rc = 0; 1176 1177 if (!pp->busy) 1178 return 0; 1179 if (count < sizeof(struct smu_user_reply_hdr)) 1180 return -EOVERFLOW; 1181 spin_lock_irqsave(&pp->lock, flags); 1182 if (pp->cmd.status == 1) { 1183 if (file->f_flags & O_NONBLOCK) { 1184 spin_unlock_irqrestore(&pp->lock, flags); 1185 return -EAGAIN; 1186 } 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