1/* 2 * PowerMac G5 SMU driver 3 * 4 * Copyright 2004 J. Mayer <l_indien@magic.fr> 5 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp. 6 * 7 * Released under the term of the GNU GPL v2. 8 */ 9 10/* 11 * TODO: 12 * - maybe add timeout to commands ? 13 * - blocking version of time functions 14 * - polling version of i2c commands (including timer that works with 15 * interrupts off) 16 * - maybe avoid some data copies with i2c by directly using the smu cmd 17 * buffer and a lower level internal interface 18 * - understand SMU -> CPU events and implement reception of them via 19 * the userland interface 20 */ 21 22#include <linux/smp_lock.h> 23#include <linux/types.h> 24#include <linux/kernel.h> 25#include <linux/device.h> 26#include <linux/dmapool.h> 27#include <linux/bootmem.h> 28#include <linux/vmalloc.h> 29#include <linux/highmem.h> 30#include <linux/jiffies.h> 31#include <linux/interrupt.h> 32#include <linux/rtc.h> 33#include <linux/completion.h> 34#include <linux/miscdevice.h> 35#include <linux/delay.h> 36#include <linux/sysdev.h> 37#include <linux/poll.h> 38#include <linux/mutex.h> 39#include <linux/of_device.h> 40#include <linux/of_platform.h> 41#include <linux/slab.h> 42 43#include <asm/byteorder.h> 44#include <asm/io.h> 45#include <asm/prom.h> 46#include <asm/machdep.h> 47#include <asm/pmac_feature.h> 48#include <asm/smu.h> 49#include <asm/sections.h> 50#include <asm/abs_addr.h> 51#include <asm/uaccess.h> 52 53#define VERSION "0.7" 54#define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp." 55 56#undef DEBUG_SMU 57 58#ifdef DEBUG_SMU 59#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0) 60#else 61#define DPRINTK(fmt, args...) do { } while (0) 62#endif 63 64/* 65 * This is the command buffer passed to the SMU hardware 66 */ 67#define SMU_MAX_DATA 254 68 69struct smu_cmd_buf { 70 u8 cmd; 71 u8 length; 72 u8 data[SMU_MAX_DATA]; 73}; 74 75struct smu_device { 76 spinlock_t lock; 77 struct device_node *of_node; 78 struct platform_device *of_dev; 79 int doorbell; /* doorbell gpio */ 80 u32 __iomem *db_buf; /* doorbell buffer */ 81 struct device_node *db_node; 82 unsigned int db_irq; 83 int msg; 84 struct device_node *msg_node; 85 unsigned int msg_irq; 86 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ 87 u32 cmd_buf_abs; /* command buffer absolute */ 88 struct list_head cmd_list; 89 struct smu_cmd *cmd_cur; /* pending command */ 90 int broken_nap; 91 struct list_head cmd_i2c_list; 92 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ 93 struct timer_list i2c_timer; 94}; 95 96/* 97 * I don't think there will ever be more than one SMU, so 98 * for now, just hard code that 99 */ 100static struct smu_device *smu; 101static DEFINE_MUTEX(smu_part_access); 102static int smu_irq_inited; 103 104static void smu_i2c_retry(unsigned long data); 105 106/* 107 * SMU driver low level stuff 108 */ 109 110static 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 165static 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 248static 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 267int 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 if (!smu_irq_inited || smu->db_irq == NO_IRQ) 285 smu_spinwait_cmd(cmd); 286 287 return 0; 288} 289EXPORT_SYMBOL(smu_queue_cmd); 290 291 292int 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} 320EXPORT_SYMBOL(smu_queue_simple); 321 322 323void 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} 334EXPORT_SYMBOL(smu_poll); 335 336 337void smu_done_complete(struct smu_cmd *cmd, void *misc) 338{ 339 struct completion *comp = misc; 340 341 complete(comp); 342} 343EXPORT_SYMBOL(smu_done_complete); 344 345 346void smu_spinwait_cmd(struct smu_cmd *cmd) 347{ 348 while(cmd->status == 1) 349 smu_poll(); 350} 351EXPORT_SYMBOL(smu_spinwait_cmd); 352 353 354/* RTC low level commands */ 355static inline int bcd2hex (int n) 356{ 357 return (((n & 0xf0) >> 4) * 10) + (n & 0xf); 358} 359 360 361static inline int hex2bcd (int n) 362{ 363 return ((n / 10) << 4) + (n % 10); 364} 365 366 367static 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 383int 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 410int 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 435void 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 451void 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 467int smu_present(void) 468{ 469 return smu != NULL; 470} 471EXPORT_SYMBOL(smu_present); 472 473 474int __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 563fail_msg_node: 564 if (smu->msg_node) 565 of_node_put(smu->msg_node); 566fail_db_node: 567 of_node_put(smu->db_node); 568fail_bootmem: 569 free_bootmem((unsigned long)smu, sizeof(struct smu_device)); 570 smu = NULL; 571fail_np: 572 of_node_put(np); 573 return ret; 574} 575 576 577static 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 */ 629core_initcall(smu_late_init); 630 631/* 632 * sysfs visibility 633 */ 634 635static 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 645static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); 646 647static int smu_platform_probe(struct platform_device* dev, 648 const struct of_device_id *match) 649{ 650 if (!smu) 651 return -ENODEV; 652 smu->of_dev = dev; 653 654 /* 655 * Ok, we are matched, now expose all i2c busses. We have to defer 656 * that unfortunately or it would deadlock inside the device model 657 */ 658 schedule_work(&smu_expose_childs_work); 659 660 return 0; 661} 662 663static const struct of_device_id smu_platform_match[] = 664{ 665 { 666 .type = "smu", 667 }, 668 {}, 669}; 670 671static struct of_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 681static 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 of_register_platform_driver(&smu_of_platform_driver); 692 return 0; 693} 694 695device_initcall(smu_init_sysfs); 696 697struct platform_device *smu_get_ofdev(void) 698{ 699 if (!smu) 700 return NULL; 701 return smu->of_dev; 702} 703 704EXPORT_SYMBOL_GPL(smu_get_ofdev); 705 706/* 707 * i2c interface 708 */ 709 710static 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 760static 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 773static 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 827int 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 906static 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 953static 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 */ 1020const 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 1052const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) 1053{ 1054 return __smu_get_sdb_partition(id, size, 0); 1055} 1056EXPORT_SYMBOL(smu_get_sdb_partition); 1057 1058 1059/* 1060 * Userland driver interface 1061 */ 1062 1063 1064static LIST_HEAD(smu_clist); 1065static DEFINE_SPINLOCK(smu_clist_lock); 1066 1067enum smu_file_mode { 1068 smu_file_commands, 1069 smu_file_events, 1070 smu_file_closing 1071}; 1072 1073struct 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 1085static 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 lock_kernel(); 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 unlock_kernel(); 1103 1104 return 0; 1105} 1106 1107 1108static 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 1116static 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 1174static 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 1230static 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 1239static 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 1252static 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 1274static 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 1317static 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 1326static struct miscdevice pmu_device = { 1327 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops 1328}; 1329 1330static 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} 1338device_initcall(smu_device_init); 1339