1 /* 2 * PowerMac G5 SMU driver 3 * 4 * Copyright 2004 J. Mayer <l_indien@magic.fr> 5 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp. 6 * 7 * Released under the term of the GNU GPL v2. 8 */ 9 10 /* 11 * TODO: 12 * - maybe add timeout to commands ? 13 * - blocking version of time functions 14 * - polling version of i2c commands (including timer that works with 15 * interrupts off) 16 * - maybe avoid some data copies with i2c by directly using the smu cmd 17 * buffer and a lower level internal interface 18 * - understand SMU -> CPU events and implement reception of them via 19 * the userland interface 20 */ 21 22 #include <linux/types.h> 23 #include <linux/kernel.h> 24 #include <linux/device.h> 25 #include <linux/dmapool.h> 26 #include <linux/bootmem.h> 27 #include <linux/vmalloc.h> 28 #include <linux/highmem.h> 29 #include <linux/jiffies.h> 30 #include <linux/interrupt.h> 31 #include <linux/rtc.h> 32 #include <linux/completion.h> 33 #include <linux/miscdevice.h> 34 #include <linux/delay.h> 35 #include <linux/sysdev.h> 36 #include <linux/poll.h> 37 #include <linux/mutex.h> 38 #include <linux/of_device.h> 39 #include <linux/of_platform.h> 40 #include <linux/slab.h> 41 42 #include <asm/byteorder.h> 43 #include <asm/io.h> 44 #include <asm/prom.h> 45 #include <asm/machdep.h> 46 #include <asm/pmac_feature.h> 47 #include <asm/smu.h> 48 #include <asm/sections.h> 49 #include <asm/abs_addr.h> 50 #include <asm/uaccess.h> 51 52 #define VERSION "0.7" 53 #define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp." 54 55 #undef DEBUG_SMU 56 57 #ifdef DEBUG_SMU 58 #define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0) 59 #else 60 #define DPRINTK(fmt, args...) do { } while (0) 61 #endif 62 63 /* 64 * This is the command buffer passed to the SMU hardware 65 */ 66 #define SMU_MAX_DATA 254 67 68 struct smu_cmd_buf { 69 u8 cmd; 70 u8 length; 71 u8 data[SMU_MAX_DATA]; 72 }; 73 74 struct smu_device { 75 spinlock_t lock; 76 struct device_node *of_node; 77 struct platform_device *of_dev; 78 int doorbell; /* doorbell gpio */ 79 u32 __iomem *db_buf; /* doorbell buffer */ 80 struct device_node *db_node; 81 unsigned int db_irq; 82 int msg; 83 struct device_node *msg_node; 84 unsigned int msg_irq; 85 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ 86 u32 cmd_buf_abs; /* command buffer absolute */ 87 struct list_head cmd_list; 88 struct smu_cmd *cmd_cur; /* pending command */ 89 int broken_nap; 90 struct list_head cmd_i2c_list; 91 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 92 struct timer_list i2c_timer; 93 }; 94 95 /* 96 * I don't think there will ever be more than one SMU, so 97 * for now, just hard code that 98 */ 99 static DEFINE_MUTEX(smu_mutex); 100 static struct smu_device *smu; 101 static DEFINE_MUTEX(smu_part_access); 102 static int smu_irq_inited; 103 104 static void smu_i2c_retry(unsigned long data); 105 106 /* 107 * SMU driver low level stuff 108 */ 109 110 static void smu_start_cmd(void) 111 { 112 unsigned long faddr, fend; 113 struct smu_cmd *cmd; 114 115 if (list_empty(&smu->cmd_list)) 116 return; 117 118 /* Fetch first command in queue */ 119 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); 120 smu->cmd_cur = cmd; 121 list_del(&cmd->link); 122 123 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, 124 cmd->data_len); 125 DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n", 126 ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1], 127 ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3], 128 ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5], 129 ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]); 130 131 /* Fill the SMU command buffer */ 132 smu->cmd_buf->cmd = cmd->cmd; 133 smu->cmd_buf->length = cmd->data_len; 134 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); 135 136 /* Flush command and data to RAM */ 137 faddr = (unsigned long)smu->cmd_buf; 138 fend = faddr + smu->cmd_buf->length + 2; 139 flush_inval_dcache_range(faddr, fend); 140 141 142 /* We also disable NAP mode for the duration of the command 143 * on U3 based machines. 144 * This is slightly racy as it can be written back to 1 by a sysctl 145 * but that never happens in practice. There seem to be an issue with 146 * U3 based machines such as the iMac G5 where napping for the 147 * whole duration of the command prevents the SMU from fetching it 148 * from memory. This might be related to the strange i2c based 149 * mechanism the SMU uses to access memory. 150 */ 151 if (smu->broken_nap) 152 powersave_nap = 0; 153 154 /* This isn't exactly a DMA mapping here, I suspect 155 * the SMU is actually communicating with us via i2c to the 156 * northbridge or the CPU to access RAM. 157 */ 158 writel(smu->cmd_buf_abs, smu->db_buf); 159 160 /* Ring the SMU doorbell */ 161 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); 162 } 163 164 165 static irqreturn_t smu_db_intr(int irq, void *arg) 166 { 167 unsigned long flags; 168 struct smu_cmd *cmd; 169 void (*done)(struct smu_cmd *cmd, void *misc) = NULL; 170 void *misc = NULL; 171 u8 gpio; 172 int rc = 0; 173 174 /* SMU completed the command, well, we hope, let's make sure 175 * of it 176 */ 177 spin_lock_irqsave(&smu->lock, flags); 178 179 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 180 if ((gpio & 7) != 7) { 181 spin_unlock_irqrestore(&smu->lock, flags); 182 return IRQ_HANDLED; 183 } 184 185 cmd = smu->cmd_cur; 186 smu->cmd_cur = NULL; 187 if (cmd == NULL) 188 goto bail; 189 190 if (rc == 0) { 191 unsigned long faddr; 192 int reply_len; 193 u8 ack; 194 195 /* CPU might have brought back the cache line, so we need 196 * to flush again before peeking at the SMU response. We 197 * flush the entire buffer for now as we haven't read the 198 * reply length (it's only 2 cache lines anyway) 199 */ 200 faddr = (unsigned long)smu->cmd_buf; 201 flush_inval_dcache_range(faddr, faddr + 256); 202 203 /* Now check ack */ 204 ack = (~cmd->cmd) & 0xff; 205 if (ack != smu->cmd_buf->cmd) { 206 DPRINTK("SMU: incorrect ack, want %x got %x\n", 207 ack, smu->cmd_buf->cmd); 208 rc = -EIO; 209 } 210 reply_len = rc == 0 ? smu->cmd_buf->length : 0; 211 DPRINTK("SMU: reply len: %d\n", reply_len); 212 if (reply_len > cmd->reply_len) { 213 printk(KERN_WARNING "SMU: reply buffer too small," 214 "got %d bytes for a %d bytes buffer\n", 215 reply_len, cmd->reply_len); 216 reply_len = cmd->reply_len; 217 } 218 cmd->reply_len = reply_len; 219 if (cmd->reply_buf && reply_len) 220 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); 221 } 222 223 /* Now complete the command. Write status last in order as we lost 224 * ownership of the command structure as soon as it's no longer -1 225 */ 226 done = cmd->done; 227 misc = cmd->misc; 228 mb(); 229 cmd->status = rc; 230 231 /* Re-enable NAP mode */ 232 if (smu->broken_nap) 233 powersave_nap = 1; 234 bail: 235 /* Start next command if any */ 236 smu_start_cmd(); 237 spin_unlock_irqrestore(&smu->lock, flags); 238 239 /* Call command completion handler if any */ 240 if (done) 241 done(cmd, misc); 242 243 /* It's an edge interrupt, nothing to do */ 244 return IRQ_HANDLED; 245 } 246 247 248 static irqreturn_t smu_msg_intr(int irq, void *arg) 249 { 250 /* I don't quite know what to do with this one, we seem to never 251 * receive it, so I suspect we have to arm it someway in the SMU 252 * to start getting events that way. 253 */ 254 255 printk(KERN_INFO "SMU: message interrupt !\n"); 256 257 /* It's an edge interrupt, nothing to do */ 258 return IRQ_HANDLED; 259 } 260 261 262 /* 263 * Queued command management. 264 * 265 */ 266 267 int smu_queue_cmd(struct smu_cmd *cmd) 268 { 269 unsigned long flags; 270 271 if (smu == NULL) 272 return -ENODEV; 273 if (cmd->data_len > SMU_MAX_DATA || 274 cmd->reply_len > SMU_MAX_DATA) 275 return -EINVAL; 276 277 cmd->status = 1; 278 spin_lock_irqsave(&smu->lock, flags); 279 list_add_tail(&cmd->link, &smu->cmd_list); 280 if (smu->cmd_cur == NULL) 281 smu_start_cmd(); 282 spin_unlock_irqrestore(&smu->lock, flags); 283 284 /* Workaround for early calls when irq isn't available */ 285 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 286 smu_spinwait_cmd(cmd); 287 288 return 0; 289 } 290 EXPORT_SYMBOL(smu_queue_cmd); 291 292 293 int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, 294 unsigned int data_len, 295 void (*done)(struct smu_cmd *cmd, void *misc), 296 void *misc, ...) 297 { 298 struct smu_cmd *cmd = &scmd->cmd; 299 va_list list; 300 int i; 301 302 if (data_len > sizeof(scmd->buffer)) 303 return -EINVAL; 304 305 memset(scmd, 0, sizeof(*scmd)); 306 cmd->cmd = command; 307 cmd->data_len = data_len; 308 cmd->data_buf = scmd->buffer; 309 cmd->reply_len = sizeof(scmd->buffer); 310 cmd->reply_buf = scmd->buffer; 311 cmd->done = done; 312 cmd->misc = misc; 313 314 va_start(list, misc); 315 for (i = 0; i < data_len; ++i) 316 scmd->buffer[i] = (u8)va_arg(list, int); 317 va_end(list); 318 319 return smu_queue_cmd(cmd); 320 } 321 EXPORT_SYMBOL(smu_queue_simple); 322 323 324 void smu_poll(void) 325 { 326 u8 gpio; 327 328 if (smu == NULL) 329 return; 330 331 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); 332 if ((gpio & 7) == 7) 333 smu_db_intr(smu->db_irq, smu); 334 } 335 EXPORT_SYMBOL(smu_poll); 336 337 338 void smu_done_complete(struct smu_cmd *cmd, void *misc) 339 { 340 struct completion *comp = misc; 341 342 complete(comp); 343 } 344 EXPORT_SYMBOL(smu_done_complete); 345 346 347 void smu_spinwait_cmd(struct smu_cmd *cmd) 348 { 349 while(cmd->status == 1) 350 smu_poll(); 351 } 352 EXPORT_SYMBOL(smu_spinwait_cmd); 353 354 355 /* RTC low level commands */ 356 static inline int bcd2hex (int n) 357 { 358 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 359 } 360 361 362 static inline int hex2bcd (int n) 363 { 364 return ((n / 10) << 4) + (n % 10); 365 } 366 367 368 static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, 369 struct rtc_time *time) 370 { 371 cmd_buf->cmd = 0x8e; 372 cmd_buf->length = 8; 373 cmd_buf->data[0] = 0x80; 374 cmd_buf->data[1] = hex2bcd(time->tm_sec); 375 cmd_buf->data[2] = hex2bcd(time->tm_min); 376 cmd_buf->data[3] = hex2bcd(time->tm_hour); 377 cmd_buf->data[4] = time->tm_wday; 378 cmd_buf->data[5] = hex2bcd(time->tm_mday); 379 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; 380 cmd_buf->data[7] = hex2bcd(time->tm_year - 100); 381 } 382 383 384 int smu_get_rtc_time(struct rtc_time *time, int spinwait) 385 { 386 struct smu_simple_cmd cmd; 387 int rc; 388 389 if (smu == NULL) 390 return -ENODEV; 391 392 memset(time, 0, sizeof(struct rtc_time)); 393 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, 394 SMU_CMD_RTC_GET_DATETIME); 395 if (rc) 396 return rc; 397 smu_spinwait_simple(&cmd); 398 399 time->tm_sec = bcd2hex(cmd.buffer[0]); 400 time->tm_min = bcd2hex(cmd.buffer[1]); 401 time->tm_hour = bcd2hex(cmd.buffer[2]); 402 time->tm_wday = bcd2hex(cmd.buffer[3]); 403 time->tm_mday = bcd2hex(cmd.buffer[4]); 404 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; 405 time->tm_year = bcd2hex(cmd.buffer[6]) + 100; 406 407 return 0; 408 } 409 410 411 int smu_set_rtc_time(struct rtc_time *time, int spinwait) 412 { 413 struct smu_simple_cmd cmd; 414 int rc; 415 416 if (smu == NULL) 417 return -ENODEV; 418 419 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, 420 SMU_CMD_RTC_SET_DATETIME, 421 hex2bcd(time->tm_sec), 422 hex2bcd(time->tm_min), 423 hex2bcd(time->tm_hour), 424 time->tm_wday, 425 hex2bcd(time->tm_mday), 426 hex2bcd(time->tm_mon) + 1, 427 hex2bcd(time->tm_year - 100)); 428 if (rc) 429 return rc; 430 smu_spinwait_simple(&cmd); 431 432 return 0; 433 } 434 435 436 void smu_shutdown(void) 437 { 438 struct smu_simple_cmd cmd; 439 440 if (smu == NULL) 441 return; 442 443 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, 444 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) 445 return; 446 smu_spinwait_simple(&cmd); 447 for (;;) 448 ; 449 } 450 451 452 void smu_restart(void) 453 { 454 struct smu_simple_cmd cmd; 455 456 if (smu == NULL) 457 return; 458 459 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, 460 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) 461 return; 462 smu_spinwait_simple(&cmd); 463 for (;;) 464 ; 465 } 466 467 468 int smu_present(void) 469 { 470 return smu != NULL; 471 } 472 EXPORT_SYMBOL(smu_present); 473 474 475 int __init smu_init (void) 476 { 477 struct device_node *np; 478 const u32 *data; 479 int ret = 0; 480 481 np = of_find_node_by_type(NULL, "smu"); 482 if (np == NULL) 483 return -ENODEV; 484 485 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR); 486 487 if (smu_cmdbuf_abs == 0) { 488 printk(KERN_ERR "SMU: Command buffer not allocated !\n"); 489 ret = -EINVAL; 490 goto fail_np; 491 } 492 493 smu = alloc_bootmem(sizeof(struct smu_device)); 494 495 spin_lock_init(&smu->lock); 496 INIT_LIST_HEAD(&smu->cmd_list); 497 INIT_LIST_HEAD(&smu->cmd_i2c_list); 498 smu->of_node = np; 499 smu->db_irq = NO_IRQ; 500 smu->msg_irq = NO_IRQ; 501 502 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a 503 * 32 bits value safely 504 */ 505 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; 506 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); 507 508 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell"); 509 if (smu->db_node == NULL) { 510 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); 511 ret = -ENXIO; 512 goto fail_bootmem; 513 } 514 data = of_get_property(smu->db_node, "reg", NULL); 515 if (data == NULL) { 516 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); 517 ret = -ENXIO; 518 goto fail_db_node; 519 } 520 521 /* Current setup has one doorbell GPIO that does both doorbell 522 * and ack. GPIOs are at 0x50, best would be to find that out 523 * in the device-tree though. 524 */ 525 smu->doorbell = *data; 526 if (smu->doorbell < 0x50) 527 smu->doorbell += 0x50; 528 529 /* Now look for the smu-interrupt GPIO */ 530 do { 531 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt"); 532 if (smu->msg_node == NULL) 533 break; 534 data = of_get_property(smu->msg_node, "reg", NULL); 535 if (data == NULL) { 536 of_node_put(smu->msg_node); 537 smu->msg_node = NULL; 538 break; 539 } 540 smu->msg = *data; 541 if (smu->msg < 0x50) 542 smu->msg += 0x50; 543 } while(0); 544 545 /* Doorbell buffer is currently hard-coded, I didn't find a proper 546 * device-tree entry giving the address. Best would probably to use 547 * an offset for K2 base though, but let's do it that way for now. 548 */ 549 smu->db_buf = ioremap(0x8000860c, 0x1000); 550 if (smu->db_buf == NULL) { 551 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); 552 ret = -ENXIO; 553 goto fail_msg_node; 554 } 555 556 /* U3 has an issue with NAP mode when issuing SMU commands */ 557 smu->broken_nap = pmac_get_uninorth_variant() < 4; 558 if (smu->broken_nap) 559 printk(KERN_INFO "SMU: using NAP mode workaround\n"); 560 561 sys_ctrler = SYS_CTRLER_SMU; 562 return 0; 563 564 fail_msg_node: 565 if (smu->msg_node) 566 of_node_put(smu->msg_node); 567 fail_db_node: 568 of_node_put(smu->db_node); 569 fail_bootmem: 570 free_bootmem((unsigned long)smu, sizeof(struct smu_device)); 571 smu = NULL; 572 fail_np: 573 of_node_put(np); 574 return ret; 575 } 576 577 578 static int smu_late_init(void) 579 { 580 if (!smu) 581 return 0; 582 583 init_timer(&smu->i2c_timer); 584 smu->i2c_timer.function = smu_i2c_retry; 585 smu->i2c_timer.data = (unsigned long)smu; 586 587 if (smu->db_node) { 588 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); 589 if (smu->db_irq == NO_IRQ) 590 printk(KERN_ERR "smu: failed to map irq for node %s\n", 591 smu->db_node->full_name); 592 } 593 if (smu->msg_node) { 594 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); 595 if (smu->msg_irq == NO_IRQ) 596 printk(KERN_ERR "smu: failed to map irq for node %s\n", 597 smu->msg_node->full_name); 598 } 599 600 /* 601 * Try to request the interrupts 602 */ 603 604 if (smu->db_irq != NO_IRQ) { 605 if (request_irq(smu->db_irq, smu_db_intr, 606 IRQF_SHARED, "SMU doorbell", smu) < 0) { 607 printk(KERN_WARNING "SMU: can't " 608 "request interrupt %d\n", 609 smu->db_irq); 610 smu->db_irq = NO_IRQ; 611 } 612 } 613 614 if (smu->msg_irq != NO_IRQ) { 615 if (request_irq(smu->msg_irq, smu_msg_intr, 616 IRQF_SHARED, "SMU message", smu) < 0) { 617 printk(KERN_WARNING "SMU: can't " 618 "request interrupt %d\n", 619 smu->msg_irq); 620 smu->msg_irq = NO_IRQ; 621 } 622 } 623 624 smu_irq_inited = 1; 625 return 0; 626 } 627 /* This has to be before arch_initcall as the low i2c stuff relies on the 628 * above having been done before we reach arch_initcalls 629 */ 630 core_initcall(smu_late_init); 631 632 /* 633 * sysfs visibility 634 */ 635 636 static void smu_expose_childs(struct work_struct *unused) 637 { 638 struct device_node *np; 639 640 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) 641 if (of_device_is_compatible(np, "smu-sensors")) 642 of_platform_device_create(np, "smu-sensors", 643 &smu->of_dev->dev); 644 } 645 646 static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 647 648 static int smu_platform_probe(struct platform_device* dev) 649 { 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 const struct of_device_id smu_platform_match[] = 664 { 665 { 666 .type = "smu", 667 }, 668 {}, 669 }; 670 671 static struct platform_driver smu_of_platform_driver = 672 { 673 .driver = { 674 .name = "smu", 675 .owner = THIS_MODULE, 676 .of_match_table = smu_platform_match, 677 }, 678 .probe = smu_platform_probe, 679 }; 680 681 static int __init smu_init_sysfs(void) 682 { 683 /* 684 * Due to sysfs bogosity, a sysdev is not a real device, so 685 * we should in fact create both if we want sysdev semantics 686 * for power management. 687 * For now, we don't power manage machines with an SMU chip, 688 * I'm a bit too far from figuring out how that works with those 689 * new chipsets, but that will come back and bite us 690 */ 691 platform_driver_register(&smu_of_platform_driver); 692 return 0; 693 } 694 695 device_initcall(smu_init_sysfs); 696 697 struct platform_device *smu_get_ofdev(void) 698 { 699 if (!smu) 700 return NULL; 701 return smu->of_dev; 702 } 703 704 EXPORT_SYMBOL_GPL(smu_get_ofdev); 705 706 /* 707 * i2c interface 708 */ 709 710 static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) 711 { 712 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; 713 void *misc = cmd->misc; 714 unsigned long flags; 715 716 /* Check for read case */ 717 if (!fail && cmd->read) { 718 if (cmd->pdata[0] < 1) 719 fail = 1; 720 else 721 memcpy(cmd->info.data, &cmd->pdata[1], 722 cmd->info.datalen); 723 } 724 725 DPRINTK("SMU: completing, success: %d\n", !fail); 726 727 /* Update status and mark no pending i2c command with lock 728 * held so nobody comes in while we dequeue an eventual 729 * pending next i2c command 730 */ 731 spin_lock_irqsave(&smu->lock, flags); 732 smu->cmd_i2c_cur = NULL; 733 wmb(); 734 cmd->status = fail ? -EIO : 0; 735 736 /* Is there another i2c command waiting ? */ 737 if (!list_empty(&smu->cmd_i2c_list)) { 738 struct smu_i2c_cmd *newcmd; 739 740 /* Fetch it, new current, remove from list */ 741 newcmd = list_entry(smu->cmd_i2c_list.next, 742 struct smu_i2c_cmd, link); 743 smu->cmd_i2c_cur = newcmd; 744 list_del(&cmd->link); 745 746 /* Queue with low level smu */ 747 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 748 if (smu->cmd_cur == NULL) 749 smu_start_cmd(); 750 } 751 spin_unlock_irqrestore(&smu->lock, flags); 752 753 /* Call command completion handler if any */ 754 if (done) 755 done(cmd, misc); 756 757 } 758 759 760 static void smu_i2c_retry(unsigned long data) 761 { 762 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; 763 764 DPRINTK("SMU: i2c failure, requeuing...\n"); 765 766 /* requeue command simply by resetting reply_len */ 767 cmd->pdata[0] = 0xff; 768 cmd->scmd.reply_len = sizeof(cmd->pdata); 769 smu_queue_cmd(&cmd->scmd); 770 } 771 772 773 static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) 774 { 775 struct smu_i2c_cmd *cmd = misc; 776 int fail = 0; 777 778 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", 779 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); 780 781 /* Check for possible status */ 782 if (scmd->status < 0) 783 fail = 1; 784 else if (cmd->read) { 785 if (cmd->stage == 0) 786 fail = cmd->pdata[0] != 0; 787 else 788 fail = cmd->pdata[0] >= 0x80; 789 } else { 790 fail = cmd->pdata[0] != 0; 791 } 792 793 /* Handle failures by requeuing command, after 5ms interval 794 */ 795 if (fail && --cmd->retries > 0) { 796 DPRINTK("SMU: i2c failure, starting timer...\n"); 797 BUG_ON(cmd != smu->cmd_i2c_cur); 798 if (!smu_irq_inited) { 799 mdelay(5); 800 smu_i2c_retry(0); 801 return; 802 } 803 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); 804 return; 805 } 806 807 /* If failure or stage 1, command is complete */ 808 if (fail || cmd->stage != 0) { 809 smu_i2c_complete_command(cmd, fail); 810 return; 811 } 812 813 DPRINTK("SMU: going to stage 1\n"); 814 815 /* Ok, initial command complete, now poll status */ 816 scmd->reply_buf = cmd->pdata; 817 scmd->reply_len = sizeof(cmd->pdata); 818 scmd->data_buf = cmd->pdata; 819 scmd->data_len = 1; 820 cmd->pdata[0] = 0; 821 cmd->stage = 1; 822 cmd->retries = 20; 823 smu_queue_cmd(scmd); 824 } 825 826 827 int smu_queue_i2c(struct smu_i2c_cmd *cmd) 828 { 829 unsigned long flags; 830 831 if (smu == NULL) 832 return -ENODEV; 833 834 /* Fill most fields of scmd */ 835 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; 836 cmd->scmd.done = smu_i2c_low_completion; 837 cmd->scmd.misc = cmd; 838 cmd->scmd.reply_buf = cmd->pdata; 839 cmd->scmd.reply_len = sizeof(cmd->pdata); 840 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; 841 cmd->scmd.status = 1; 842 cmd->stage = 0; 843 cmd->pdata[0] = 0xff; 844 cmd->retries = 20; 845 cmd->status = 1; 846 847 /* Check transfer type, sanitize some "info" fields 848 * based on transfer type and do more checking 849 */ 850 cmd->info.caddr = cmd->info.devaddr; 851 cmd->read = cmd->info.devaddr & 0x01; 852 switch(cmd->info.type) { 853 case SMU_I2C_TRANSFER_SIMPLE: 854 memset(&cmd->info.sublen, 0, 4); 855 break; 856 case SMU_I2C_TRANSFER_COMBINED: 857 cmd->info.devaddr &= 0xfe; 858 case SMU_I2C_TRANSFER_STDSUB: 859 if (cmd->info.sublen > 3) 860 return -EINVAL; 861 break; 862 default: 863 return -EINVAL; 864 } 865 866 /* Finish setting up command based on transfer direction 867 */ 868 if (cmd->read) { 869 if (cmd->info.datalen > SMU_I2C_READ_MAX) 870 return -EINVAL; 871 memset(cmd->info.data, 0xff, cmd->info.datalen); 872 cmd->scmd.data_len = 9; 873 } else { 874 if (cmd->info.datalen > SMU_I2C_WRITE_MAX) 875 return -EINVAL; 876 cmd->scmd.data_len = 9 + cmd->info.datalen; 877 } 878 879 DPRINTK("SMU: i2c enqueuing command\n"); 880 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", 881 cmd->read ? "read" : "write", cmd->info.datalen, 882 cmd->info.bus, cmd->info.caddr, 883 cmd->info.subaddr[0], cmd->info.type); 884 885 886 /* Enqueue command in i2c list, and if empty, enqueue also in 887 * main command list 888 */ 889 spin_lock_irqsave(&smu->lock, flags); 890 if (smu->cmd_i2c_cur == NULL) { 891 smu->cmd_i2c_cur = cmd; 892 list_add_tail(&cmd->scmd.link, &smu->cmd_list); 893 if (smu->cmd_cur == NULL) 894 smu_start_cmd(); 895 } else 896 list_add_tail(&cmd->link, &smu->cmd_i2c_list); 897 spin_unlock_irqrestore(&smu->lock, flags); 898 899 return 0; 900 } 901 902 /* 903 * Handling of "partitions" 904 */ 905 906 static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) 907 { 908 DECLARE_COMPLETION_ONSTACK(comp); 909 unsigned int chunk; 910 struct smu_cmd cmd; 911 int rc; 912 u8 params[8]; 913 914 /* We currently use a chunk size of 0xe. We could check the 915 * SMU firmware version and use bigger sizes though 916 */ 917 chunk = 0xe; 918 919 while (len) { 920 unsigned int clen = min(len, chunk); 921 922 cmd.cmd = SMU_CMD_MISC_ee_COMMAND; 923 cmd.data_len = 7; 924 cmd.data_buf = params; 925 cmd.reply_len = chunk; 926 cmd.reply_buf = dest; 927 cmd.done = smu_done_complete; 928 cmd.misc = ∁ 929 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; 930 params[1] = 0x4; 931 *((u32 *)¶ms[2]) = addr; 932 params[6] = clen; 933 934 rc = smu_queue_cmd(&cmd); 935 if (rc) 936 return rc; 937 wait_for_completion(&comp); 938 if (cmd.status != 0) 939 return rc; 940 if (cmd.reply_len != clen) { 941 printk(KERN_DEBUG "SMU: short read in " 942 "smu_read_datablock, got: %d, want: %d\n", 943 cmd.reply_len, clen); 944 return -EIO; 945 } 946 len -= clen; 947 addr += clen; 948 dest += clen; 949 } 950 return 0; 951 } 952 953 static struct smu_sdbp_header *smu_create_sdb_partition(int id) 954 { 955 DECLARE_COMPLETION_ONSTACK(comp); 956 struct smu_simple_cmd cmd; 957 unsigned int addr, len, tlen; 958 struct smu_sdbp_header *hdr; 959 struct property *prop; 960 961 /* First query the partition info */ 962 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); 963 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, 964 smu_done_complete, &comp, 965 SMU_CMD_PARTITION_LATEST, id); 966 wait_for_completion(&comp); 967 DPRINTK("SMU: done, status: %d, reply_len: %d\n", 968 cmd.cmd.status, cmd.cmd.reply_len); 969 970 /* Partition doesn't exist (or other error) */ 971 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) 972 return NULL; 973 974 /* Fetch address and length from reply */ 975 addr = *((u16 *)cmd.buffer); 976 len = cmd.buffer[3] << 2; 977 /* Calucluate total length to allocate, including the 17 bytes 978 * for "sdb-partition-XX" that we append at the end of the buffer 979 */ 980 tlen = sizeof(struct property) + len + 18; 981 982 prop = kzalloc(tlen, GFP_KERNEL); 983 if (prop == NULL) 984 return NULL; 985 hdr = (struct smu_sdbp_header *)(prop + 1); 986 prop->name = ((char *)prop) + tlen - 18; 987 sprintf(prop->name, "sdb-partition-%02x", id); 988 prop->length = len; 989 prop->value = hdr; 990 prop->next = NULL; 991 992 /* Read the datablock */ 993 if (smu_read_datablock((u8 *)hdr, addr, len)) { 994 printk(KERN_DEBUG "SMU: datablock read failed while reading " 995 "partition %02x !\n", id); 996 goto failure; 997 } 998 999 /* Got it, check a few things and create the property */ 1000 if (hdr->id != id) { 1001 printk(KERN_DEBUG "SMU: Reading partition %02x and got " 1002 "%02x !\n", id, hdr->id); 1003 goto failure; 1004 } 1005 if (prom_add_property(smu->of_node, prop)) { 1006 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " 1007 "property !\n", id); 1008 goto failure; 1009 } 1010 1011 return hdr; 1012 failure: 1013 kfree(prop); 1014 return NULL; 1015 } 1016 1017 /* Note: Only allowed to return error code in pointers (using ERR_PTR) 1018 * when interruptible is 1 1019 */ 1020 const struct smu_sdbp_header *__smu_get_sdb_partition(int id, 1021 unsigned int *size, int interruptible) 1022 { 1023 char pname[32]; 1024 const struct smu_sdbp_header *part; 1025 1026 if (!smu) 1027 return NULL; 1028 1029 sprintf(pname, "sdb-partition-%02x", id); 1030 1031 DPRINTK("smu_get_sdb_partition(%02x)\n", id); 1032 1033 if (interruptible) { 1034 int rc; 1035 rc = mutex_lock_interruptible(&smu_part_access); 1036 if (rc) 1037 return ERR_PTR(rc); 1038 } else 1039 mutex_lock(&smu_part_access); 1040 1041 part = of_get_property(smu->of_node, pname, size); 1042 if (part == NULL) { 1043 DPRINTK("trying to extract from SMU ...\n"); 1044 part = smu_create_sdb_partition(id); 1045 if (part != NULL && size) 1046 *size = part->len << 2; 1047 } 1048 mutex_unlock(&smu_part_access); 1049 return part; 1050 } 1051 1052 const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1053 { 1054 return __smu_get_sdb_partition(id, size, 0); 1055 } 1056 EXPORT_SYMBOL(smu_get_sdb_partition); 1057 1058 1059 /* 1060 * Userland driver interface 1061 */ 1062 1063 1064 static LIST_HEAD(smu_clist); 1065 static DEFINE_SPINLOCK(smu_clist_lock); 1066 1067 enum smu_file_mode { 1068 smu_file_commands, 1069 smu_file_events, 1070 smu_file_closing 1071 }; 1072 1073 struct smu_private 1074 { 1075 struct list_head list; 1076 enum smu_file_mode mode; 1077 int busy; 1078 struct smu_cmd cmd; 1079 spinlock_t lock; 1080 wait_queue_head_t wait; 1081 u8 buffer[SMU_MAX_DATA]; 1082 }; 1083 1084 1085 static int smu_open(struct inode *inode, struct file *file) 1086 { 1087 struct smu_private *pp; 1088 unsigned long flags; 1089 1090 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); 1091 if (pp == 0) 1092 return -ENOMEM; 1093 spin_lock_init(&pp->lock); 1094 pp->mode = smu_file_commands; 1095 init_waitqueue_head(&pp->wait); 1096 1097 mutex_lock(&smu_mutex); 1098 spin_lock_irqsave(&smu_clist_lock, flags); 1099 list_add(&pp->list, &smu_clist); 1100 spin_unlock_irqrestore(&smu_clist_lock, flags); 1101 file->private_data = pp; 1102 mutex_unlock(&smu_mutex); 1103 1104 return 0; 1105 } 1106 1107 1108 static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) 1109 { 1110 struct smu_private *pp = misc; 1111 1112 wake_up_all(&pp->wait); 1113 } 1114 1115 1116 static ssize_t smu_write(struct file *file, const char __user *buf, 1117 size_t count, loff_t *ppos) 1118 { 1119 struct smu_private *pp = file->private_data; 1120 unsigned long flags; 1121 struct smu_user_cmd_hdr hdr; 1122 int rc = 0; 1123 1124 if (pp->busy) 1125 return -EBUSY; 1126 else if (copy_from_user(&hdr, buf, sizeof(hdr))) 1127 return -EFAULT; 1128 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { 1129 pp->mode = smu_file_events; 1130 return 0; 1131 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { 1132 const struct smu_sdbp_header *part; 1133 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); 1134 if (part == NULL) 1135 return -EINVAL; 1136 else if (IS_ERR(part)) 1137 return PTR_ERR(part); 1138 return 0; 1139 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) 1140 return -EINVAL; 1141 else if (pp->mode != smu_file_commands) 1142 return -EBADFD; 1143 else if (hdr.data_len > SMU_MAX_DATA) 1144 return -EINVAL; 1145 1146 spin_lock_irqsave(&pp->lock, flags); 1147 if (pp->busy) { 1148 spin_unlock_irqrestore(&pp->lock, flags); 1149 return -EBUSY; 1150 } 1151 pp->busy = 1; 1152 pp->cmd.status = 1; 1153 spin_unlock_irqrestore(&pp->lock, flags); 1154 1155 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { 1156 pp->busy = 0; 1157 return -EFAULT; 1158 } 1159 1160 pp->cmd.cmd = hdr.cmd; 1161 pp->cmd.data_len = hdr.data_len; 1162 pp->cmd.reply_len = SMU_MAX_DATA; 1163 pp->cmd.data_buf = pp->buffer; 1164 pp->cmd.reply_buf = pp->buffer; 1165 pp->cmd.done = smu_user_cmd_done; 1166 pp->cmd.misc = pp; 1167 rc = smu_queue_cmd(&pp->cmd); 1168 if (rc < 0) 1169 return rc; 1170 return count; 1171 } 1172 1173 1174 static ssize_t smu_read_command(struct file *file, struct smu_private *pp, 1175 char __user *buf, size_t count) 1176 { 1177 DECLARE_WAITQUEUE(wait, current); 1178 struct smu_user_reply_hdr hdr; 1179 unsigned long flags; 1180 int size, rc = 0; 1181 1182 if (!pp->busy) 1183 return 0; 1184 if (count < sizeof(struct smu_user_reply_hdr)) 1185 return -EOVERFLOW; 1186 spin_lock_irqsave(&pp->lock, flags); 1187 if (pp->cmd.status == 1) { 1188 if (file->f_flags & O_NONBLOCK) { 1189 spin_unlock_irqrestore(&pp->lock, flags); 1190 return -EAGAIN; 1191 } 1192 add_wait_queue(&pp->wait, &wait); 1193 for (;;) { 1194 set_current_state(TASK_INTERRUPTIBLE); 1195 rc = 0; 1196 if (pp->cmd.status != 1) 1197 break; 1198 rc = -ERESTARTSYS; 1199 if (signal_pending(current)) 1200 break; 1201 spin_unlock_irqrestore(&pp->lock, flags); 1202 schedule(); 1203 spin_lock_irqsave(&pp->lock, flags); 1204 } 1205 set_current_state(TASK_RUNNING); 1206 remove_wait_queue(&pp->wait, &wait); 1207 } 1208 spin_unlock_irqrestore(&pp->lock, flags); 1209 if (rc) 1210 return rc; 1211 if (pp->cmd.status != 0) 1212 pp->cmd.reply_len = 0; 1213 size = sizeof(hdr) + pp->cmd.reply_len; 1214 if (count < size) 1215 size = count; 1216 rc = size; 1217 hdr.status = pp->cmd.status; 1218 hdr.reply_len = pp->cmd.reply_len; 1219 if (copy_to_user(buf, &hdr, sizeof(hdr))) 1220 return -EFAULT; 1221 size -= sizeof(hdr); 1222 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) 1223 return -EFAULT; 1224 pp->busy = 0; 1225 1226 return rc; 1227 } 1228 1229 1230 static ssize_t smu_read_events(struct file *file, struct smu_private *pp, 1231 char __user *buf, size_t count) 1232 { 1233 /* Not implemented */ 1234 msleep_interruptible(1000); 1235 return 0; 1236 } 1237 1238 1239 static ssize_t smu_read(struct file *file, char __user *buf, 1240 size_t count, loff_t *ppos) 1241 { 1242 struct smu_private *pp = file->private_data; 1243 1244 if (pp->mode == smu_file_commands) 1245 return smu_read_command(file, pp, buf, count); 1246 if (pp->mode == smu_file_events) 1247 return smu_read_events(file, pp, buf, count); 1248 1249 return -EBADFD; 1250 } 1251 1252 static unsigned int smu_fpoll(struct file *file, poll_table *wait) 1253 { 1254 struct smu_private *pp = file->private_data; 1255 unsigned int mask = 0; 1256 unsigned long flags; 1257 1258 if (pp == 0) 1259 return 0; 1260 1261 if (pp->mode == smu_file_commands) { 1262 poll_wait(file, &pp->wait, wait); 1263 1264 spin_lock_irqsave(&pp->lock, flags); 1265 if (pp->busy && pp->cmd.status != 1) 1266 mask |= POLLIN; 1267 spin_unlock_irqrestore(&pp->lock, flags); 1268 } if (pp->mode == smu_file_events) { 1269 /* Not yet implemented */ 1270 } 1271 return mask; 1272 } 1273 1274 static int smu_release(struct inode *inode, struct file *file) 1275 { 1276 struct smu_private *pp = file->private_data; 1277 unsigned long flags; 1278 unsigned int busy; 1279 1280 if (pp == 0) 1281 return 0; 1282 1283 file->private_data = NULL; 1284 1285 /* Mark file as closing to avoid races with new request */ 1286 spin_lock_irqsave(&pp->lock, flags); 1287 pp->mode = smu_file_closing; 1288 busy = pp->busy; 1289 1290 /* Wait for any pending request to complete */ 1291 if (busy && pp->cmd.status == 1) { 1292 DECLARE_WAITQUEUE(wait, current); 1293 1294 add_wait_queue(&pp->wait, &wait); 1295 for (;;) { 1296 set_current_state(TASK_UNINTERRUPTIBLE); 1297 if (pp->cmd.status != 1) 1298 break; 1299 spin_unlock_irqrestore(&pp->lock, flags); 1300 schedule(); 1301 spin_lock_irqsave(&pp->lock, flags); 1302 } 1303 set_current_state(TASK_RUNNING); 1304 remove_wait_queue(&pp->wait, &wait); 1305 } 1306 spin_unlock_irqrestore(&pp->lock, flags); 1307 1308 spin_lock_irqsave(&smu_clist_lock, flags); 1309 list_del(&pp->list); 1310 spin_unlock_irqrestore(&smu_clist_lock, flags); 1311 kfree(pp); 1312 1313 return 0; 1314 } 1315 1316 1317 static const struct file_operations smu_device_fops = { 1318 .llseek = no_llseek, 1319 .read = smu_read, 1320 .write = smu_write, 1321 .poll = smu_fpoll, 1322 .open = smu_open, 1323 .release = smu_release, 1324 }; 1325 1326 static struct miscdevice pmu_device = { 1327 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1328 }; 1329 1330 static int smu_device_init(void) 1331 { 1332 if (!smu) 1333 return -ENODEV; 1334 if (misc_register(&pmu_device) < 0) 1335 printk(KERN_ERR "via-pmu: cannot register misc device.\n"); 1336 return 0; 1337 } 1338 device_initcall(smu_device_init); 1339