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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_irq.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/uaccess.h>
50
51#define VERSION "0.7"
52#define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
53
54#undef DEBUG_SMU
55
56#ifdef DEBUG_SMU
57#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
58#else
59#define DPRINTK(fmt, args...) do { } while (0)
60#endif
61
62/*
63 * This is the command buffer passed to the SMU hardware
64 */
65#define SMU_MAX_DATA 254
66
67struct smu_cmd_buf {
68 u8 cmd;
69 u8 length;
70 u8 data[SMU_MAX_DATA];
71};
72
73struct smu_device {
74 spinlock_t lock;
75 struct device_node *of_node;
76 struct platform_device *of_dev;
77 int doorbell; /* doorbell gpio */
78 u32 __iomem *db_buf; /* doorbell buffer */
79 struct device_node *db_node;
80 unsigned int db_irq;
81 int msg;
82 struct device_node *msg_node;
83 unsigned int msg_irq;
84 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */
85 u32 cmd_buf_abs; /* command buffer absolute */
86 struct list_head cmd_list;
87 struct smu_cmd *cmd_cur; /* pending command */
88 int broken_nap;
89 struct list_head cmd_i2c_list;
90 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */
91 struct timer_list i2c_timer;
92};
93
94/*
95 * I don't think there will ever be more than one SMU, so
96 * for now, just hard code that
97 */
98static DEFINE_MUTEX(smu_mutex);
99static struct smu_device *smu;
100static DEFINE_MUTEX(smu_part_access);
101static int smu_irq_inited;
102
103static void smu_i2c_retry(unsigned long data);
104
105/*
106 * SMU driver low level stuff
107 */
108
109static void smu_start_cmd(void)
110{
111 unsigned long faddr, fend;
112 struct smu_cmd *cmd;
113
114 if (list_empty(&smu->cmd_list))
115 return;
116
117 /* Fetch first command in queue */
118 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
119 smu->cmd_cur = cmd;
120 list_del(&cmd->link);
121
122 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
123 cmd->data_len);
124 DPRINTK("SMU: data buffer: %8ph\n", cmd->data_buf);
125
126 /* Fill the SMU command buffer */
127 smu->cmd_buf->cmd = cmd->cmd;
128 smu->cmd_buf->length = cmd->data_len;
129 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
130
131 /* Flush command and data to RAM */
132 faddr = (unsigned long)smu->cmd_buf;
133 fend = faddr + smu->cmd_buf->length + 2;
134 flush_inval_dcache_range(faddr, fend);
135
136
137 /* We also disable NAP mode for the duration of the command
138 * on U3 based machines.
139 * This is slightly racy as it can be written back to 1 by a sysctl
140 * but that never happens in practice. There seem to be an issue with
141 * U3 based machines such as the iMac G5 where napping for the
142 * whole duration of the command prevents the SMU from fetching it
143 * from memory. This might be related to the strange i2c based
144 * mechanism the SMU uses to access memory.
145 */
146 if (smu->broken_nap)
147 powersave_nap = 0;
148
149 /* This isn't exactly a DMA mapping here, I suspect
150 * the SMU is actually communicating with us via i2c to the
151 * northbridge or the CPU to access RAM.
152 */
153 writel(smu->cmd_buf_abs, smu->db_buf);
154
155 /* Ring the SMU doorbell */
156 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
157}
158
159
160static irqreturn_t smu_db_intr(int irq, void *arg)
161{
162 unsigned long flags;
163 struct smu_cmd *cmd;
164 void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
165 void *misc = NULL;
166 u8 gpio;
167 int rc = 0;
168
169 /* SMU completed the command, well, we hope, let's make sure
170 * of it
171 */
172 spin_lock_irqsave(&smu->lock, flags);
173
174 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
175 if ((gpio & 7) != 7) {
176 spin_unlock_irqrestore(&smu->lock, flags);
177 return IRQ_HANDLED;
178 }
179
180 cmd = smu->cmd_cur;
181 smu->cmd_cur = NULL;
182 if (cmd == NULL)
183 goto bail;
184
185 if (rc == 0) {
186 unsigned long faddr;
187 int reply_len;
188 u8 ack;
189
190 /* CPU might have brought back the cache line, so we need
191 * to flush again before peeking at the SMU response. We
192 * flush the entire buffer for now as we haven't read the
193 * reply length (it's only 2 cache lines anyway)
194 */
195 faddr = (unsigned long)smu->cmd_buf;
196 flush_inval_dcache_range(faddr, faddr + 256);
197
198 /* Now check ack */
199 ack = (~cmd->cmd) & 0xff;
200 if (ack != smu->cmd_buf->cmd) {
201 DPRINTK("SMU: incorrect ack, want %x got %x\n",
202 ack, smu->cmd_buf->cmd);
203 rc = -EIO;
204 }
205 reply_len = rc == 0 ? smu->cmd_buf->length : 0;
206 DPRINTK("SMU: reply len: %d\n", reply_len);
207 if (reply_len > cmd->reply_len) {
208 printk(KERN_WARNING "SMU: reply buffer too small,"
209 "got %d bytes for a %d bytes buffer\n",
210 reply_len, cmd->reply_len);
211 reply_len = cmd->reply_len;
212 }
213 cmd->reply_len = reply_len;
214 if (cmd->reply_buf && reply_len)
215 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
216 }
217
218 /* Now complete the command. Write status last in order as we lost
219 * ownership of the command structure as soon as it's no longer -1
220 */
221 done = cmd->done;
222 misc = cmd->misc;
223 mb();
224 cmd->status = rc;
225
226 /* Re-enable NAP mode */
227 if (smu->broken_nap)
228 powersave_nap = 1;
229 bail:
230 /* Start next command if any */
231 smu_start_cmd();
232 spin_unlock_irqrestore(&smu->lock, flags);
233
234 /* Call command completion handler if any */
235 if (done)
236 done(cmd, misc);
237
238 /* It's an edge interrupt, nothing to do */
239 return IRQ_HANDLED;
240}
241
242
243static irqreturn_t smu_msg_intr(int irq, void *arg)
244{
245 /* I don't quite know what to do with this one, we seem to never
246 * receive it, so I suspect we have to arm it someway in the SMU
247 * to start getting events that way.
248 */
249
250 printk(KERN_INFO "SMU: message interrupt !\n");
251
252 /* It's an edge interrupt, nothing to do */
253 return IRQ_HANDLED;
254}
255
256
257/*
258 * Queued command management.
259 *
260 */
261
262int smu_queue_cmd(struct smu_cmd *cmd)
263{
264 unsigned long flags;
265
266 if (smu == NULL)
267 return -ENODEV;
268 if (cmd->data_len > SMU_MAX_DATA ||
269 cmd->reply_len > SMU_MAX_DATA)
270 return -EINVAL;
271
272 cmd->status = 1;
273 spin_lock_irqsave(&smu->lock, flags);
274 list_add_tail(&cmd->link, &smu->cmd_list);
275 if (smu->cmd_cur == NULL)
276 smu_start_cmd();
277 spin_unlock_irqrestore(&smu->lock, flags);
278
279 /* Workaround for early calls when irq isn't available */
280 if (!smu_irq_inited || smu->db_irq == NO_IRQ)
281 smu_spinwait_cmd(cmd);
282
283 return 0;
284}
285EXPORT_SYMBOL(smu_queue_cmd);
286
287
288int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
289 unsigned int data_len,
290 void (*done)(struct smu_cmd *cmd, void *misc),
291 void *misc, ...)
292{
293 struct smu_cmd *cmd = &scmd->cmd;
294 va_list list;
295 int i;
296
297 if (data_len > sizeof(scmd->buffer))
298 return -EINVAL;
299
300 memset(scmd, 0, sizeof(*scmd));
301 cmd->cmd = command;
302 cmd->data_len = data_len;
303 cmd->data_buf = scmd->buffer;
304 cmd->reply_len = sizeof(scmd->buffer);
305 cmd->reply_buf = scmd->buffer;
306 cmd->done = done;
307 cmd->misc = misc;
308
309 va_start(list, misc);
310 for (i = 0; i < data_len; ++i)
311 scmd->buffer[i] = (u8)va_arg(list, int);
312 va_end(list);
313
314 return smu_queue_cmd(cmd);
315}
316EXPORT_SYMBOL(smu_queue_simple);
317
318
319void smu_poll(void)
320{
321 u8 gpio;
322
323 if (smu == NULL)
324 return;
325
326 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
327 if ((gpio & 7) == 7)
328 smu_db_intr(smu->db_irq, smu);
329}
330EXPORT_SYMBOL(smu_poll);
331
332
333void smu_done_complete(struct smu_cmd *cmd, void *misc)
334{
335 struct completion *comp = misc;
336
337 complete(comp);
338}
339EXPORT_SYMBOL(smu_done_complete);
340
341
342void smu_spinwait_cmd(struct smu_cmd *cmd)
343{
344 while(cmd->status == 1)
345 smu_poll();
346}
347EXPORT_SYMBOL(smu_spinwait_cmd);
348
349
350/* RTC low level commands */
351static inline int bcd2hex (int n)
352{
353 return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
354}
355
356
357static inline int hex2bcd (int n)
358{
359 return ((n / 10) << 4) + (n % 10);
360}
361
362
363static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
364 struct rtc_time *time)
365{
366 cmd_buf->cmd = 0x8e;
367 cmd_buf->length = 8;
368 cmd_buf->data[0] = 0x80;
369 cmd_buf->data[1] = hex2bcd(time->tm_sec);
370 cmd_buf->data[2] = hex2bcd(time->tm_min);
371 cmd_buf->data[3] = hex2bcd(time->tm_hour);
372 cmd_buf->data[4] = time->tm_wday;
373 cmd_buf->data[5] = hex2bcd(time->tm_mday);
374 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
375 cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
376}
377
378
379int smu_get_rtc_time(struct rtc_time *time, int spinwait)
380{
381 struct smu_simple_cmd cmd;
382 int rc;
383
384 if (smu == NULL)
385 return -ENODEV;
386
387 memset(time, 0, sizeof(struct rtc_time));
388 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
389 SMU_CMD_RTC_GET_DATETIME);
390 if (rc)
391 return rc;
392 smu_spinwait_simple(&cmd);
393
394 time->tm_sec = bcd2hex(cmd.buffer[0]);
395 time->tm_min = bcd2hex(cmd.buffer[1]);
396 time->tm_hour = bcd2hex(cmd.buffer[2]);
397 time->tm_wday = bcd2hex(cmd.buffer[3]);
398 time->tm_mday = bcd2hex(cmd.buffer[4]);
399 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
400 time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
401
402 return 0;
403}
404
405
406int smu_set_rtc_time(struct rtc_time *time, int spinwait)
407{
408 struct smu_simple_cmd cmd;
409 int rc;
410
411 if (smu == NULL)
412 return -ENODEV;
413
414 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
415 SMU_CMD_RTC_SET_DATETIME,
416 hex2bcd(time->tm_sec),
417 hex2bcd(time->tm_min),
418 hex2bcd(time->tm_hour),
419 time->tm_wday,
420 hex2bcd(time->tm_mday),
421 hex2bcd(time->tm_mon) + 1,
422 hex2bcd(time->tm_year - 100));
423 if (rc)
424 return rc;
425 smu_spinwait_simple(&cmd);
426
427 return 0;
428}
429
430
431void smu_shutdown(void)
432{
433 struct smu_simple_cmd cmd;
434
435 if (smu == NULL)
436 return;
437
438 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
439 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
440 return;
441 smu_spinwait_simple(&cmd);
442 for (;;)
443 ;
444}
445
446
447void smu_restart(void)
448{
449 struct smu_simple_cmd cmd;
450
451 if (smu == NULL)
452 return;
453
454 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
455 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
456 return;
457 smu_spinwait_simple(&cmd);
458 for (;;)
459 ;
460}
461
462
463int smu_present(void)
464{
465 return smu != NULL;
466}
467EXPORT_SYMBOL(smu_present);
468
469
470int __init smu_init (void)
471{
472 struct device_node *np;
473 const u32 *data;
474 int ret = 0;
475
476 np = of_find_node_by_type(NULL, "smu");
477 if (np == NULL)
478 return -ENODEV;
479
480 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
481
482 if (smu_cmdbuf_abs == 0) {
483 printk(KERN_ERR "SMU: Command buffer not allocated !\n");
484 ret = -EINVAL;
485 goto fail_np;
486 }
487
488 smu = alloc_bootmem(sizeof(struct smu_device));
489
490 spin_lock_init(&smu->lock);
491 INIT_LIST_HEAD(&smu->cmd_list);
492 INIT_LIST_HEAD(&smu->cmd_i2c_list);
493 smu->of_node = np;
494 smu->db_irq = NO_IRQ;
495 smu->msg_irq = NO_IRQ;
496
497 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
498 * 32 bits value safely
499 */
500 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
501 smu->cmd_buf = __va(smu_cmdbuf_abs);
502
503 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
504 if (smu->db_node == NULL) {
505 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
506 ret = -ENXIO;
507 goto fail_bootmem;
508 }
509 data = of_get_property(smu->db_node, "reg", NULL);
510 if (data == NULL) {
511 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
512 ret = -ENXIO;
513 goto fail_db_node;
514 }
515
516 /* Current setup has one doorbell GPIO that does both doorbell
517 * and ack. GPIOs are at 0x50, best would be to find that out
518 * in the device-tree though.
519 */
520 smu->doorbell = *data;
521 if (smu->doorbell < 0x50)
522 smu->doorbell += 0x50;
523
524 /* Now look for the smu-interrupt GPIO */
525 do {
526 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
527 if (smu->msg_node == NULL)
528 break;
529 data = of_get_property(smu->msg_node, "reg", NULL);
530 if (data == NULL) {
531 of_node_put(smu->msg_node);
532 smu->msg_node = NULL;
533 break;
534 }
535 smu->msg = *data;
536 if (smu->msg < 0x50)
537 smu->msg += 0x50;
538 } while(0);
539
540 /* Doorbell buffer is currently hard-coded, I didn't find a proper
541 * device-tree entry giving the address. Best would probably to use
542 * an offset for K2 base though, but let's do it that way for now.
543 */
544 smu->db_buf = ioremap(0x8000860c, 0x1000);
545 if (smu->db_buf == NULL) {
546 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
547 ret = -ENXIO;
548 goto fail_msg_node;
549 }
550
551 /* U3 has an issue with NAP mode when issuing SMU commands */
552 smu->broken_nap = pmac_get_uninorth_variant() < 4;
553 if (smu->broken_nap)
554 printk(KERN_INFO "SMU: using NAP mode workaround\n");
555
556 sys_ctrler = SYS_CTRLER_SMU;
557 return 0;
558
559fail_msg_node:
560 of_node_put(smu->msg_node);
561fail_db_node:
562 of_node_put(smu->db_node);
563fail_bootmem:
564 free_bootmem(__pa(smu), sizeof(struct smu_device));
565 smu = NULL;
566fail_np:
567 of_node_put(np);
568 return ret;
569}
570
571
572static int smu_late_init(void)
573{
574 if (!smu)
575 return 0;
576
577 init_timer(&smu->i2c_timer);
578 smu->i2c_timer.function = smu_i2c_retry;
579 smu->i2c_timer.data = (unsigned long)smu;
580
581 if (smu->db_node) {
582 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
583 if (smu->db_irq == NO_IRQ)
584 printk(KERN_ERR "smu: failed to map irq for node %s\n",
585 smu->db_node->full_name);
586 }
587 if (smu->msg_node) {
588 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
589 if (smu->msg_irq == NO_IRQ)
590 printk(KERN_ERR "smu: failed to map irq for node %s\n",
591 smu->msg_node->full_name);
592 }
593
594 /*
595 * Try to request the interrupts
596 */
597
598 if (smu->db_irq != NO_IRQ) {
599 if (request_irq(smu->db_irq, smu_db_intr,
600 IRQF_SHARED, "SMU doorbell", smu) < 0) {
601 printk(KERN_WARNING "SMU: can't "
602 "request interrupt %d\n",
603 smu->db_irq);
604 smu->db_irq = NO_IRQ;
605 }
606 }
607
608 if (smu->msg_irq != NO_IRQ) {
609 if (request_irq(smu->msg_irq, smu_msg_intr,
610 IRQF_SHARED, "SMU message", smu) < 0) {
611 printk(KERN_WARNING "SMU: can't "
612 "request interrupt %d\n",
613 smu->msg_irq);
614 smu->msg_irq = NO_IRQ;
615 }
616 }
617
618 smu_irq_inited = 1;
619 return 0;
620}
621/* This has to be before arch_initcall as the low i2c stuff relies on the
622 * above having been done before we reach arch_initcalls
623 */
624core_initcall(smu_late_init);
625
626/*
627 * sysfs visibility
628 */
629
630static void smu_expose_childs(struct work_struct *unused)
631{
632 struct device_node *np;
633
634 for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;)
635 if (of_device_is_compatible(np, "smu-sensors"))
636 of_platform_device_create(np, "smu-sensors",
637 &smu->of_dev->dev);
638}
639
640static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs);
641
642static int smu_platform_probe(struct platform_device* dev)
643{
644 if (!smu)
645 return -ENODEV;
646 smu->of_dev = dev;
647
648 /*
649 * Ok, we are matched, now expose all i2c busses. We have to defer
650 * that unfortunately or it would deadlock inside the device model
651 */
652 schedule_work(&smu_expose_childs_work);
653
654 return 0;
655}
656
657static const struct of_device_id smu_platform_match[] =
658{
659 {
660 .type = "smu",
661 },
662 {},
663};
664
665static struct platform_driver smu_of_platform_driver =
666{
667 .driver = {
668 .name = "smu",
669 .of_match_table = smu_platform_match,
670 },
671 .probe = smu_platform_probe,
672};
673
674static int __init smu_init_sysfs(void)
675{
676 /*
677 * For now, we don't power manage machines with an SMU chip,
678 * I'm a bit too far from figuring out how that works with those
679 * new chipsets, but that will come back and bite us
680 */
681 platform_driver_register(&smu_of_platform_driver);
682 return 0;
683}
684
685device_initcall(smu_init_sysfs);
686
687struct platform_device *smu_get_ofdev(void)
688{
689 if (!smu)
690 return NULL;
691 return smu->of_dev;
692}
693
694EXPORT_SYMBOL_GPL(smu_get_ofdev);
695
696/*
697 * i2c interface
698 */
699
700static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
701{
702 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
703 void *misc = cmd->misc;
704 unsigned long flags;
705
706 /* Check for read case */
707 if (!fail && cmd->read) {
708 if (cmd->pdata[0] < 1)
709 fail = 1;
710 else
711 memcpy(cmd->info.data, &cmd->pdata[1],
712 cmd->info.datalen);
713 }
714
715 DPRINTK("SMU: completing, success: %d\n", !fail);
716
717 /* Update status and mark no pending i2c command with lock
718 * held so nobody comes in while we dequeue an eventual
719 * pending next i2c command
720 */
721 spin_lock_irqsave(&smu->lock, flags);
722 smu->cmd_i2c_cur = NULL;
723 wmb();
724 cmd->status = fail ? -EIO : 0;
725
726 /* Is there another i2c command waiting ? */
727 if (!list_empty(&smu->cmd_i2c_list)) {
728 struct smu_i2c_cmd *newcmd;
729
730 /* Fetch it, new current, remove from list */
731 newcmd = list_entry(smu->cmd_i2c_list.next,
732 struct smu_i2c_cmd, link);
733 smu->cmd_i2c_cur = newcmd;
734 list_del(&cmd->link);
735
736 /* Queue with low level smu */
737 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
738 if (smu->cmd_cur == NULL)
739 smu_start_cmd();
740 }
741 spin_unlock_irqrestore(&smu->lock, flags);
742
743 /* Call command completion handler if any */
744 if (done)
745 done(cmd, misc);
746
747}
748
749
750static void smu_i2c_retry(unsigned long data)
751{
752 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur;
753
754 DPRINTK("SMU: i2c failure, requeuing...\n");
755
756 /* requeue command simply by resetting reply_len */
757 cmd->pdata[0] = 0xff;
758 cmd->scmd.reply_len = sizeof(cmd->pdata);
759 smu_queue_cmd(&cmd->scmd);
760}
761
762
763static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
764{
765 struct smu_i2c_cmd *cmd = misc;
766 int fail = 0;
767
768 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
769 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
770
771 /* Check for possible status */
772 if (scmd->status < 0)
773 fail = 1;
774 else if (cmd->read) {
775 if (cmd->stage == 0)
776 fail = cmd->pdata[0] != 0;
777 else
778 fail = cmd->pdata[0] >= 0x80;
779 } else {
780 fail = cmd->pdata[0] != 0;
781 }
782
783 /* Handle failures by requeuing command, after 5ms interval
784 */
785 if (fail && --cmd->retries > 0) {
786 DPRINTK("SMU: i2c failure, starting timer...\n");
787 BUG_ON(cmd != smu->cmd_i2c_cur);
788 if (!smu_irq_inited) {
789 mdelay(5);
790 smu_i2c_retry(0);
791 return;
792 }
793 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));
794 return;
795 }
796
797 /* If failure or stage 1, command is complete */
798 if (fail || cmd->stage != 0) {
799 smu_i2c_complete_command(cmd, fail);
800 return;
801 }
802
803 DPRINTK("SMU: going to stage 1\n");
804
805 /* Ok, initial command complete, now poll status */
806 scmd->reply_buf = cmd->pdata;
807 scmd->reply_len = sizeof(cmd->pdata);
808 scmd->data_buf = cmd->pdata;
809 scmd->data_len = 1;
810 cmd->pdata[0] = 0;
811 cmd->stage = 1;
812 cmd->retries = 20;
813 smu_queue_cmd(scmd);
814}
815
816
817int smu_queue_i2c(struct smu_i2c_cmd *cmd)
818{
819 unsigned long flags;
820
821 if (smu == NULL)
822 return -ENODEV;
823
824 /* Fill most fields of scmd */
825 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
826 cmd->scmd.done = smu_i2c_low_completion;
827 cmd->scmd.misc = cmd;
828 cmd->scmd.reply_buf = cmd->pdata;
829 cmd->scmd.reply_len = sizeof(cmd->pdata);
830 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
831 cmd->scmd.status = 1;
832 cmd->stage = 0;
833 cmd->pdata[0] = 0xff;
834 cmd->retries = 20;
835 cmd->status = 1;
836
837 /* Check transfer type, sanitize some "info" fields
838 * based on transfer type and do more checking
839 */
840 cmd->info.caddr = cmd->info.devaddr;
841 cmd->read = cmd->info.devaddr & 0x01;
842 switch(cmd->info.type) {
843 case SMU_I2C_TRANSFER_SIMPLE:
844 memset(&cmd->info.sublen, 0, 4);
845 break;
846 case SMU_I2C_TRANSFER_COMBINED:
847 cmd->info.devaddr &= 0xfe;
848 case SMU_I2C_TRANSFER_STDSUB:
849 if (cmd->info.sublen > 3)
850 return -EINVAL;
851 break;
852 default:
853 return -EINVAL;
854 }
855
856 /* Finish setting up command based on transfer direction
857 */
858 if (cmd->read) {
859 if (cmd->info.datalen > SMU_I2C_READ_MAX)
860 return -EINVAL;
861 memset(cmd->info.data, 0xff, cmd->info.datalen);
862 cmd->scmd.data_len = 9;
863 } else {
864 if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
865 return -EINVAL;
866 cmd->scmd.data_len = 9 + cmd->info.datalen;
867 }
868
869 DPRINTK("SMU: i2c enqueuing command\n");
870 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
871 cmd->read ? "read" : "write", cmd->info.datalen,
872 cmd->info.bus, cmd->info.caddr,
873 cmd->info.subaddr[0], cmd->info.type);
874
875
876 /* Enqueue command in i2c list, and if empty, enqueue also in
877 * main command list
878 */
879 spin_lock_irqsave(&smu->lock, flags);
880 if (smu->cmd_i2c_cur == NULL) {
881 smu->cmd_i2c_cur = cmd;
882 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
883 if (smu->cmd_cur == NULL)
884 smu_start_cmd();
885 } else
886 list_add_tail(&cmd->link, &smu->cmd_i2c_list);
887 spin_unlock_irqrestore(&smu->lock, flags);
888
889 return 0;
890}
891
892/*
893 * Handling of "partitions"
894 */
895
896static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)
897{
898 DECLARE_COMPLETION_ONSTACK(comp);
899 unsigned int chunk;
900 struct smu_cmd cmd;
901 int rc;
902 u8 params[8];
903
904 /* We currently use a chunk size of 0xe. We could check the
905 * SMU firmware version and use bigger sizes though
906 */
907 chunk = 0xe;
908
909 while (len) {
910 unsigned int clen = min(len, chunk);
911
912 cmd.cmd = SMU_CMD_MISC_ee_COMMAND;
913 cmd.data_len = 7;
914 cmd.data_buf = params;
915 cmd.reply_len = chunk;
916 cmd.reply_buf = dest;
917 cmd.done = smu_done_complete;
918 cmd.misc = ∁
919 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;
920 params[1] = 0x4;
921 *((u32 *)¶ms[2]) = addr;
922 params[6] = clen;
923
924 rc = smu_queue_cmd(&cmd);
925 if (rc)
926 return rc;
927 wait_for_completion(&comp);
928 if (cmd.status != 0)
929 return rc;
930 if (cmd.reply_len != clen) {
931 printk(KERN_DEBUG "SMU: short read in "
932 "smu_read_datablock, got: %d, want: %d\n",
933 cmd.reply_len, clen);
934 return -EIO;
935 }
936 len -= clen;
937 addr += clen;
938 dest += clen;
939 }
940 return 0;
941}
942
943static struct smu_sdbp_header *smu_create_sdb_partition(int id)
944{
945 DECLARE_COMPLETION_ONSTACK(comp);
946 struct smu_simple_cmd cmd;
947 unsigned int addr, len, tlen;
948 struct smu_sdbp_header *hdr;
949 struct property *prop;
950
951 /* First query the partition info */
952 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);
953 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,
954 smu_done_complete, &comp,
955 SMU_CMD_PARTITION_LATEST, id);
956 wait_for_completion(&comp);
957 DPRINTK("SMU: done, status: %d, reply_len: %d\n",
958 cmd.cmd.status, cmd.cmd.reply_len);
959
960 /* Partition doesn't exist (or other error) */
961 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)
962 return NULL;
963
964 /* Fetch address and length from reply */
965 addr = *((u16 *)cmd.buffer);
966 len = cmd.buffer[3] << 2;
967 /* Calucluate total length to allocate, including the 17 bytes
968 * for "sdb-partition-XX" that we append at the end of the buffer
969 */
970 tlen = sizeof(struct property) + len + 18;
971
972 prop = kzalloc(tlen, GFP_KERNEL);
973 if (prop == NULL)
974 return NULL;
975 hdr = (struct smu_sdbp_header *)(prop + 1);
976 prop->name = ((char *)prop) + tlen - 18;
977 sprintf(prop->name, "sdb-partition-%02x", id);
978 prop->length = len;
979 prop->value = hdr;
980 prop->next = NULL;
981
982 /* Read the datablock */
983 if (smu_read_datablock((u8 *)hdr, addr, len)) {
984 printk(KERN_DEBUG "SMU: datablock read failed while reading "
985 "partition %02x !\n", id);
986 goto failure;
987 }
988
989 /* Got it, check a few things and create the property */
990 if (hdr->id != id) {
991 printk(KERN_DEBUG "SMU: Reading partition %02x and got "
992 "%02x !\n", id, hdr->id);
993 goto failure;
994 }
995 if (of_add_property(smu->of_node, prop)) {
996 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "
997 "property !\n", id);
998 goto failure;
999 }
1000
1001 return hdr;
1002 failure:
1003 kfree(prop);
1004 return NULL;
1005}
1006
1007/* Note: Only allowed to return error code in pointers (using ERR_PTR)
1008 * when interruptible is 1
1009 */
1010const struct smu_sdbp_header *__smu_get_sdb_partition(int id,
1011 unsigned int *size, int interruptible)
1012{
1013 char pname[32];
1014 const struct smu_sdbp_header *part;
1015
1016 if (!smu)
1017 return NULL;
1018
1019 sprintf(pname, "sdb-partition-%02x", id);
1020
1021 DPRINTK("smu_get_sdb_partition(%02x)\n", id);
1022
1023 if (interruptible) {
1024 int rc;
1025 rc = mutex_lock_interruptible(&smu_part_access);
1026 if (rc)
1027 return ERR_PTR(rc);
1028 } else
1029 mutex_lock(&smu_part_access);
1030
1031 part = of_get_property(smu->of_node, pname, size);
1032 if (part == NULL) {
1033 DPRINTK("trying to extract from SMU ...\n");
1034 part = smu_create_sdb_partition(id);
1035 if (part != NULL && size)
1036 *size = part->len << 2;
1037 }
1038 mutex_unlock(&smu_part_access);
1039 return part;
1040}
1041
1042const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)
1043{
1044 return __smu_get_sdb_partition(id, size, 0);
1045}
1046EXPORT_SYMBOL(smu_get_sdb_partition);
1047
1048
1049/*
1050 * Userland driver interface
1051 */
1052
1053
1054static LIST_HEAD(smu_clist);
1055static DEFINE_SPINLOCK(smu_clist_lock);
1056
1057enum smu_file_mode {
1058 smu_file_commands,
1059 smu_file_events,
1060 smu_file_closing
1061};
1062
1063struct smu_private
1064{
1065 struct list_head list;
1066 enum smu_file_mode mode;
1067 int busy;
1068 struct smu_cmd cmd;
1069 spinlock_t lock;
1070 wait_queue_head_t wait;
1071 u8 buffer[SMU_MAX_DATA];
1072};
1073
1074
1075static int smu_open(struct inode *inode, struct file *file)
1076{
1077 struct smu_private *pp;
1078 unsigned long flags;
1079
1080 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL);
1081 if (pp == 0)
1082 return -ENOMEM;
1083 spin_lock_init(&pp->lock);
1084 pp->mode = smu_file_commands;
1085 init_waitqueue_head(&pp->wait);
1086
1087 mutex_lock(&smu_mutex);
1088 spin_lock_irqsave(&smu_clist_lock, flags);
1089 list_add(&pp->list, &smu_clist);
1090 spin_unlock_irqrestore(&smu_clist_lock, flags);
1091 file->private_data = pp;
1092 mutex_unlock(&smu_mutex);
1093
1094 return 0;
1095}
1096
1097
1098static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
1099{
1100 struct smu_private *pp = misc;
1101
1102 wake_up_all(&pp->wait);
1103}
1104
1105
1106static ssize_t smu_write(struct file *file, const char __user *buf,
1107 size_t count, loff_t *ppos)
1108{
1109 struct smu_private *pp = file->private_data;
1110 unsigned long flags;
1111 struct smu_user_cmd_hdr hdr;
1112 int rc = 0;
1113
1114 if (pp->busy)
1115 return -EBUSY;
1116 else if (copy_from_user(&hdr, buf, sizeof(hdr)))
1117 return -EFAULT;
1118 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
1119 pp->mode = smu_file_events;
1120 return 0;
1121 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {
1122 const struct smu_sdbp_header *part;
1123 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);
1124 if (part == NULL)
1125 return -EINVAL;
1126 else if (IS_ERR(part))
1127 return PTR_ERR(part);
1128 return 0;
1129 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
1130 return -EINVAL;
1131 else if (pp->mode != smu_file_commands)
1132 return -EBADFD;
1133 else if (hdr.data_len > SMU_MAX_DATA)
1134 return -EINVAL;
1135
1136 spin_lock_irqsave(&pp->lock, flags);
1137 if (pp->busy) {
1138 spin_unlock_irqrestore(&pp->lock, flags);
1139 return -EBUSY;
1140 }
1141 pp->busy = 1;
1142 pp->cmd.status = 1;
1143 spin_unlock_irqrestore(&pp->lock, flags);
1144
1145 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
1146 pp->busy = 0;
1147 return -EFAULT;
1148 }
1149
1150 pp->cmd.cmd = hdr.cmd;
1151 pp->cmd.data_len = hdr.data_len;
1152 pp->cmd.reply_len = SMU_MAX_DATA;
1153 pp->cmd.data_buf = pp->buffer;
1154 pp->cmd.reply_buf = pp->buffer;
1155 pp->cmd.done = smu_user_cmd_done;
1156 pp->cmd.misc = pp;
1157 rc = smu_queue_cmd(&pp->cmd);
1158 if (rc < 0)
1159 return rc;
1160 return count;
1161}
1162
1163
1164static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
1165 char __user *buf, size_t count)
1166{
1167 DECLARE_WAITQUEUE(wait, current);
1168 struct smu_user_reply_hdr hdr;
1169 unsigned long flags;
1170 int size, rc = 0;
1171
1172 if (!pp->busy)
1173 return 0;
1174 if (count < sizeof(struct smu_user_reply_hdr))
1175 return -EOVERFLOW;
1176 spin_lock_irqsave(&pp->lock, flags);
1177 if (pp->cmd.status == 1) {
1178 if (file->f_flags & O_NONBLOCK) {
1179 spin_unlock_irqrestore(&pp->lock, flags);
1180 return -EAGAIN;
1181 }
1182 add_wait_queue(&pp->wait, &wait);
1183 for (;;) {
1184 set_current_state(TASK_INTERRUPTIBLE);
1185 rc = 0;
1186 if (pp->cmd.status != 1)
1187 break;
1188 rc = -ERESTARTSYS;
1189 if (signal_pending(current))
1190 break;
1191 spin_unlock_irqrestore(&pp->lock, flags);
1192 schedule();
1193 spin_lock_irqsave(&pp->lock, flags);
1194 }
1195 set_current_state(TASK_RUNNING);
1196 remove_wait_queue(&pp->wait, &wait);
1197 }
1198 spin_unlock_irqrestore(&pp->lock, flags);
1199 if (rc)
1200 return rc;
1201 if (pp->cmd.status != 0)
1202 pp->cmd.reply_len = 0;
1203 size = sizeof(hdr) + pp->cmd.reply_len;
1204 if (count < size)
1205 size = count;
1206 rc = size;
1207 hdr.status = pp->cmd.status;
1208 hdr.reply_len = pp->cmd.reply_len;
1209 if (copy_to_user(buf, &hdr, sizeof(hdr)))
1210 return -EFAULT;
1211 size -= sizeof(hdr);
1212 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1213 return -EFAULT;
1214 pp->busy = 0;
1215
1216 return rc;
1217}
1218
1219
1220static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1221 char __user *buf, size_t count)
1222{
1223 /* Not implemented */
1224 msleep_interruptible(1000);
1225 return 0;
1226}
1227
1228
1229static ssize_t smu_read(struct file *file, char __user *buf,
1230 size_t count, loff_t *ppos)
1231{
1232 struct smu_private *pp = file->private_data;
1233
1234 if (pp->mode == smu_file_commands)
1235 return smu_read_command(file, pp, buf, count);
1236 if (pp->mode == smu_file_events)
1237 return smu_read_events(file, pp, buf, count);
1238
1239 return -EBADFD;
1240}
1241
1242static unsigned int smu_fpoll(struct file *file, poll_table *wait)
1243{
1244 struct smu_private *pp = file->private_data;
1245 unsigned int mask = 0;
1246 unsigned long flags;
1247
1248 if (pp == 0)
1249 return 0;
1250
1251 if (pp->mode == smu_file_commands) {
1252 poll_wait(file, &pp->wait, wait);
1253
1254 spin_lock_irqsave(&pp->lock, flags);
1255 if (pp->busy && pp->cmd.status != 1)
1256 mask |= POLLIN;
1257 spin_unlock_irqrestore(&pp->lock, flags);
1258 }
1259 if (pp->mode == smu_file_events) {
1260 /* Not yet implemented */
1261 }
1262 return mask;
1263}
1264
1265static int smu_release(struct inode *inode, struct file *file)
1266{
1267 struct smu_private *pp = file->private_data;
1268 unsigned long flags;
1269 unsigned int busy;
1270
1271 if (pp == 0)
1272 return 0;
1273
1274 file->private_data = NULL;
1275
1276 /* Mark file as closing to avoid races with new request */
1277 spin_lock_irqsave(&pp->lock, flags);
1278 pp->mode = smu_file_closing;
1279 busy = pp->busy;
1280
1281 /* Wait for any pending request to complete */
1282 if (busy && pp->cmd.status == 1) {
1283 DECLARE_WAITQUEUE(wait, current);
1284
1285 add_wait_queue(&pp->wait, &wait);
1286 for (;;) {
1287 set_current_state(TASK_UNINTERRUPTIBLE);
1288 if (pp->cmd.status != 1)
1289 break;
1290 spin_unlock_irqrestore(&pp->lock, flags);
1291 schedule();
1292 spin_lock_irqsave(&pp->lock, flags);
1293 }
1294 set_current_state(TASK_RUNNING);
1295 remove_wait_queue(&pp->wait, &wait);
1296 }
1297 spin_unlock_irqrestore(&pp->lock, flags);
1298
1299 spin_lock_irqsave(&smu_clist_lock, flags);
1300 list_del(&pp->list);
1301 spin_unlock_irqrestore(&smu_clist_lock, flags);
1302 kfree(pp);
1303
1304 return 0;
1305}
1306
1307
1308static const struct file_operations smu_device_fops = {
1309 .llseek = no_llseek,
1310 .read = smu_read,
1311 .write = smu_write,
1312 .poll = smu_fpoll,
1313 .open = smu_open,
1314 .release = smu_release,
1315};
1316
1317static struct miscdevice pmu_device = {
1318 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1319};
1320
1321static int smu_device_init(void)
1322{
1323 if (!smu)
1324 return -ENODEV;
1325 if (misc_register(&pmu_device) < 0)
1326 printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1327 return 0;
1328}
1329device_initcall(smu_device_init);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PowerMac G5 SMU driver
4 *
5 * Copyright 2004 J. Mayer <l_indien@magic.fr>
6 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
7 */
8
9/*
10 * TODO:
11 * - maybe add timeout to commands ?
12 * - blocking version of time functions
13 * - polling version of i2c commands (including timer that works with
14 * interrupts off)
15 * - maybe avoid some data copies with i2c by directly using the smu cmd
16 * buffer and a lower level internal interface
17 * - understand SMU -> CPU events and implement reception of them via
18 * the userland interface
19 */
20
21#include <linux/types.h>
22#include <linux/kernel.h>
23#include <linux/device.h>
24#include <linux/dmapool.h>
25#include <linux/memblock.h>
26#include <linux/vmalloc.h>
27#include <linux/highmem.h>
28#include <linux/jiffies.h>
29#include <linux/interrupt.h>
30#include <linux/rtc.h>
31#include <linux/completion.h>
32#include <linux/miscdevice.h>
33#include <linux/delay.h>
34#include <linux/poll.h>
35#include <linux/mutex.h>
36#include <linux/of.h>
37#include <linux/of_address.h>
38#include <linux/of_irq.h>
39#include <linux/of_platform.h>
40#include <linux/platform_device.h>
41#include <linux/slab.h>
42#include <linux/sched/signal.h>
43
44#include <asm/byteorder.h>
45#include <asm/io.h>
46#include <asm/machdep.h>
47#include <asm/pmac_feature.h>
48#include <asm/smu.h>
49#include <asm/sections.h>
50#include <linux/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
68struct smu_cmd_buf {
69 u8 cmd;
70 u8 length;
71 u8 data[SMU_MAX_DATA];
72};
73
74struct 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 */
99static DEFINE_MUTEX(smu_mutex);
100static struct smu_device *smu;
101static DEFINE_MUTEX(smu_part_access);
102static int smu_irq_inited;
103static unsigned long smu_cmdbuf_abs;
104
105static void smu_i2c_retry(struct timer_list *t);
106
107/*
108 * SMU driver low level stuff
109 */
110
111static void smu_start_cmd(void)
112{
113 unsigned long faddr, fend;
114 struct smu_cmd *cmd;
115
116 if (list_empty(&smu->cmd_list))
117 return;
118
119 /* Fetch first command in queue */
120 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
121 smu->cmd_cur = cmd;
122 list_del(&cmd->link);
123
124 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
125 cmd->data_len);
126 DPRINTK("SMU: data buffer: %8ph\n", cmd->data_buf);
127
128 /* Fill the SMU command buffer */
129 smu->cmd_buf->cmd = cmd->cmd;
130 smu->cmd_buf->length = cmd->data_len;
131 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
132
133 /* Flush command and data to RAM */
134 faddr = (unsigned long)smu->cmd_buf;
135 fend = faddr + smu->cmd_buf->length + 2;
136 flush_dcache_range(faddr, fend);
137
138
139 /* We also disable NAP mode for the duration of the command
140 * on U3 based machines.
141 * This is slightly racy as it can be written back to 1 by a sysctl
142 * but that never happens in practice. There seem to be an issue with
143 * U3 based machines such as the iMac G5 where napping for the
144 * whole duration of the command prevents the SMU from fetching it
145 * from memory. This might be related to the strange i2c based
146 * mechanism the SMU uses to access memory.
147 */
148 if (smu->broken_nap)
149 powersave_nap = 0;
150
151 /* This isn't exactly a DMA mapping here, I suspect
152 * the SMU is actually communicating with us via i2c to the
153 * northbridge or the CPU to access RAM.
154 */
155 writel(smu->cmd_buf_abs, smu->db_buf);
156
157 /* Ring the SMU doorbell */
158 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
159}
160
161
162static irqreturn_t smu_db_intr(int irq, void *arg)
163{
164 unsigned long flags;
165 struct smu_cmd *cmd;
166 void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
167 void *misc = NULL;
168 u8 gpio;
169 int rc = 0;
170
171 /* SMU completed the command, well, we hope, let's make sure
172 * of it
173 */
174 spin_lock_irqsave(&smu->lock, flags);
175
176 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
177 if ((gpio & 7) != 7) {
178 spin_unlock_irqrestore(&smu->lock, flags);
179 return IRQ_HANDLED;
180 }
181
182 cmd = smu->cmd_cur;
183 smu->cmd_cur = NULL;
184 if (cmd == NULL)
185 goto bail;
186
187 if (rc == 0) {
188 unsigned long faddr;
189 int reply_len;
190 u8 ack;
191
192 /* CPU might have brought back the cache line, so we need
193 * to flush again before peeking at the SMU response. We
194 * flush the entire buffer for now as we haven't read the
195 * reply length (it's only 2 cache lines anyway)
196 */
197 faddr = (unsigned long)smu->cmd_buf;
198 flush_dcache_range(faddr, faddr + 256);
199
200 /* Now check ack */
201 ack = (~cmd->cmd) & 0xff;
202 if (ack != smu->cmd_buf->cmd) {
203 DPRINTK("SMU: incorrect ack, want %x got %x\n",
204 ack, smu->cmd_buf->cmd);
205 rc = -EIO;
206 }
207 reply_len = rc == 0 ? smu->cmd_buf->length : 0;
208 DPRINTK("SMU: reply len: %d\n", reply_len);
209 if (reply_len > cmd->reply_len) {
210 printk(KERN_WARNING "SMU: reply buffer too small,"
211 "got %d bytes for a %d bytes buffer\n",
212 reply_len, cmd->reply_len);
213 reply_len = cmd->reply_len;
214 }
215 cmd->reply_len = reply_len;
216 if (cmd->reply_buf && reply_len)
217 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
218 }
219
220 /* Now complete the command. Write status last in order as we lost
221 * ownership of the command structure as soon as it's no longer -1
222 */
223 done = cmd->done;
224 misc = cmd->misc;
225 mb();
226 cmd->status = rc;
227
228 /* Re-enable NAP mode */
229 if (smu->broken_nap)
230 powersave_nap = 1;
231 bail:
232 /* Start next command if any */
233 smu_start_cmd();
234 spin_unlock_irqrestore(&smu->lock, flags);
235
236 /* Call command completion handler if any */
237 if (done)
238 done(cmd, misc);
239
240 /* It's an edge interrupt, nothing to do */
241 return IRQ_HANDLED;
242}
243
244
245static irqreturn_t smu_msg_intr(int irq, void *arg)
246{
247 /* I don't quite know what to do with this one, we seem to never
248 * receive it, so I suspect we have to arm it someway in the SMU
249 * to start getting events that way.
250 */
251
252 printk(KERN_INFO "SMU: message interrupt !\n");
253
254 /* It's an edge interrupt, nothing to do */
255 return IRQ_HANDLED;
256}
257
258
259/*
260 * Queued command management.
261 *
262 */
263
264int smu_queue_cmd(struct smu_cmd *cmd)
265{
266 unsigned long flags;
267
268 if (smu == NULL)
269 return -ENODEV;
270 if (cmd->data_len > SMU_MAX_DATA ||
271 cmd->reply_len > SMU_MAX_DATA)
272 return -EINVAL;
273
274 cmd->status = 1;
275 spin_lock_irqsave(&smu->lock, flags);
276 list_add_tail(&cmd->link, &smu->cmd_list);
277 if (smu->cmd_cur == NULL)
278 smu_start_cmd();
279 spin_unlock_irqrestore(&smu->lock, flags);
280
281 /* Workaround for early calls when irq isn't available */
282 if (!smu_irq_inited || !smu->db_irq)
283 smu_spinwait_cmd(cmd);
284
285 return 0;
286}
287EXPORT_SYMBOL(smu_queue_cmd);
288
289
290int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
291 unsigned int data_len,
292 void (*done)(struct smu_cmd *cmd, void *misc),
293 void *misc, ...)
294{
295 struct smu_cmd *cmd = &scmd->cmd;
296 va_list list;
297 int i;
298
299 if (data_len > sizeof(scmd->buffer))
300 return -EINVAL;
301
302 memset(scmd, 0, sizeof(*scmd));
303 cmd->cmd = command;
304 cmd->data_len = data_len;
305 cmd->data_buf = scmd->buffer;
306 cmd->reply_len = sizeof(scmd->buffer);
307 cmd->reply_buf = scmd->buffer;
308 cmd->done = done;
309 cmd->misc = misc;
310
311 va_start(list, misc);
312 for (i = 0; i < data_len; ++i)
313 scmd->buffer[i] = (u8)va_arg(list, int);
314 va_end(list);
315
316 return smu_queue_cmd(cmd);
317}
318EXPORT_SYMBOL(smu_queue_simple);
319
320
321void smu_poll(void)
322{
323 u8 gpio;
324
325 if (smu == NULL)
326 return;
327
328 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
329 if ((gpio & 7) == 7)
330 smu_db_intr(smu->db_irq, smu);
331}
332EXPORT_SYMBOL(smu_poll);
333
334
335void smu_done_complete(struct smu_cmd *cmd, void *misc)
336{
337 struct completion *comp = misc;
338
339 complete(comp);
340}
341EXPORT_SYMBOL(smu_done_complete);
342
343
344void smu_spinwait_cmd(struct smu_cmd *cmd)
345{
346 while(cmd->status == 1)
347 smu_poll();
348}
349EXPORT_SYMBOL(smu_spinwait_cmd);
350
351
352/* RTC low level commands */
353static inline int bcd2hex (int n)
354{
355 return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
356}
357
358
359static inline int hex2bcd (int n)
360{
361 return ((n / 10) << 4) + (n % 10);
362}
363
364
365static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
366 struct rtc_time *time)
367{
368 cmd_buf->cmd = 0x8e;
369 cmd_buf->length = 8;
370 cmd_buf->data[0] = 0x80;
371 cmd_buf->data[1] = hex2bcd(time->tm_sec);
372 cmd_buf->data[2] = hex2bcd(time->tm_min);
373 cmd_buf->data[3] = hex2bcd(time->tm_hour);
374 cmd_buf->data[4] = time->tm_wday;
375 cmd_buf->data[5] = hex2bcd(time->tm_mday);
376 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
377 cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
378}
379
380
381int smu_get_rtc_time(struct rtc_time *time, int spinwait)
382{
383 struct smu_simple_cmd cmd;
384 int rc;
385
386 if (smu == NULL)
387 return -ENODEV;
388
389 memset(time, 0, sizeof(struct rtc_time));
390 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
391 SMU_CMD_RTC_GET_DATETIME);
392 if (rc)
393 return rc;
394 smu_spinwait_simple(&cmd);
395
396 time->tm_sec = bcd2hex(cmd.buffer[0]);
397 time->tm_min = bcd2hex(cmd.buffer[1]);
398 time->tm_hour = bcd2hex(cmd.buffer[2]);
399 time->tm_wday = bcd2hex(cmd.buffer[3]);
400 time->tm_mday = bcd2hex(cmd.buffer[4]);
401 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
402 time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
403
404 return 0;
405}
406
407
408int smu_set_rtc_time(struct rtc_time *time, int spinwait)
409{
410 struct smu_simple_cmd cmd;
411 int rc;
412
413 if (smu == NULL)
414 return -ENODEV;
415
416 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
417 SMU_CMD_RTC_SET_DATETIME,
418 hex2bcd(time->tm_sec),
419 hex2bcd(time->tm_min),
420 hex2bcd(time->tm_hour),
421 time->tm_wday,
422 hex2bcd(time->tm_mday),
423 hex2bcd(time->tm_mon) + 1,
424 hex2bcd(time->tm_year - 100));
425 if (rc)
426 return rc;
427 smu_spinwait_simple(&cmd);
428
429 return 0;
430}
431
432
433void smu_shutdown(void)
434{
435 struct smu_simple_cmd cmd;
436
437 if (smu == NULL)
438 return;
439
440 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
441 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
442 return;
443 smu_spinwait_simple(&cmd);
444 for (;;)
445 ;
446}
447
448
449void smu_restart(void)
450{
451 struct smu_simple_cmd cmd;
452
453 if (smu == NULL)
454 return;
455
456 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
457 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
458 return;
459 smu_spinwait_simple(&cmd);
460 for (;;)
461 ;
462}
463
464
465int smu_present(void)
466{
467 return smu != NULL;
468}
469EXPORT_SYMBOL(smu_present);
470
471
472int __init smu_init (void)
473{
474 struct device_node *np;
475 u64 data;
476 int ret = 0;
477
478 np = of_find_node_by_type(NULL, "smu");
479 if (np == NULL)
480 return -ENODEV;
481
482 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
483
484 /*
485 * SMU based G5s need some memory below 2Gb. Thankfully this is
486 * called at a time where memblock is still available.
487 */
488 smu_cmdbuf_abs = memblock_phys_alloc_range(4096, 4096, 0, 0x80000000UL);
489 if (smu_cmdbuf_abs == 0) {
490 printk(KERN_ERR "SMU: Command buffer allocation failed !\n");
491 ret = -EINVAL;
492 goto fail_np;
493 }
494
495 smu = memblock_alloc(sizeof(struct smu_device), SMP_CACHE_BYTES);
496 if (!smu)
497 panic("%s: Failed to allocate %zu bytes\n", __func__,
498 sizeof(struct smu_device));
499
500 spin_lock_init(&smu->lock);
501 INIT_LIST_HEAD(&smu->cmd_list);
502 INIT_LIST_HEAD(&smu->cmd_i2c_list);
503 smu->of_node = np;
504 smu->db_irq = 0;
505 smu->msg_irq = 0;
506
507 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
508 * 32 bits value safely
509 */
510 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
511 smu->cmd_buf = __va(smu_cmdbuf_abs);
512
513 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
514 if (smu->db_node == NULL) {
515 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
516 ret = -ENXIO;
517 goto fail_bootmem;
518 }
519 if (of_property_read_reg(smu->db_node, 0, &data, NULL)) {
520 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
521 ret = -ENXIO;
522 goto fail_db_node;
523 }
524
525 /* Current setup has one doorbell GPIO that does both doorbell
526 * and ack. GPIOs are at 0x50, best would be to find that out
527 * in the device-tree though.
528 */
529 smu->doorbell = data;
530 if (smu->doorbell < 0x50)
531 smu->doorbell += 0x50;
532
533 /* Now look for the smu-interrupt GPIO */
534 do {
535 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
536 if (smu->msg_node == NULL)
537 break;
538 if (of_property_read_reg(smu->msg_node, 0, &data, NULL)) {
539 of_node_put(smu->msg_node);
540 smu->msg_node = NULL;
541 break;
542 }
543 smu->msg = data;
544 if (smu->msg < 0x50)
545 smu->msg += 0x50;
546 } while(0);
547
548 /* Doorbell buffer is currently hard-coded, I didn't find a proper
549 * device-tree entry giving the address. Best would probably to use
550 * an offset for K2 base though, but let's do it that way for now.
551 */
552 smu->db_buf = ioremap(0x8000860c, 0x1000);
553 if (smu->db_buf == NULL) {
554 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
555 ret = -ENXIO;
556 goto fail_msg_node;
557 }
558
559 /* U3 has an issue with NAP mode when issuing SMU commands */
560 smu->broken_nap = pmac_get_uninorth_variant() < 4;
561 if (smu->broken_nap)
562 printk(KERN_INFO "SMU: using NAP mode workaround\n");
563
564 sys_ctrler = SYS_CTRLER_SMU;
565 return 0;
566
567fail_msg_node:
568 of_node_put(smu->msg_node);
569fail_db_node:
570 of_node_put(smu->db_node);
571fail_bootmem:
572 memblock_free(smu, sizeof(struct smu_device));
573 smu = NULL;
574fail_np:
575 of_node_put(np);
576 return ret;
577}
578
579
580static int smu_late_init(void)
581{
582 if (!smu)
583 return 0;
584
585 timer_setup(&smu->i2c_timer, smu_i2c_retry, 0);
586
587 if (smu->db_node) {
588 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
589 if (!smu->db_irq)
590 printk(KERN_ERR "smu: failed to map irq for node %pOF\n",
591 smu->db_node);
592 }
593 if (smu->msg_node) {
594 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
595 if (!smu->msg_irq)
596 printk(KERN_ERR "smu: failed to map irq for node %pOF\n",
597 smu->msg_node);
598 }
599
600 /*
601 * Try to request the interrupts
602 */
603
604 if (smu->db_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 = 0;
611 }
612 }
613
614 if (smu->msg_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 = 0;
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 */
630core_initcall(smu_late_init);
631
632/*
633 * sysfs visibility
634 */
635
636static void smu_expose_childs(struct work_struct *unused)
637{
638 struct device_node *np;
639
640 for_each_child_of_node(smu->of_node, np)
641 if (of_device_is_compatible(np, "smu-sensors"))
642 of_platform_device_create(np, "smu-sensors",
643 &smu->of_dev->dev);
644}
645
646static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs);
647
648static 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
663static const struct of_device_id smu_platform_match[] =
664{
665 {
666 .type = "smu",
667 },
668 {},
669};
670
671static struct platform_driver smu_of_platform_driver =
672{
673 .driver = {
674 .name = "smu",
675 .of_match_table = smu_platform_match,
676 },
677 .probe = smu_platform_probe,
678};
679
680static int __init smu_init_sysfs(void)
681{
682 /*
683 * For now, we don't power manage machines with an SMU chip,
684 * I'm a bit too far from figuring out how that works with those
685 * new chipsets, but that will come back and bite us
686 */
687 platform_driver_register(&smu_of_platform_driver);
688 return 0;
689}
690
691device_initcall(smu_init_sysfs);
692
693struct platform_device *smu_get_ofdev(void)
694{
695 if (!smu)
696 return NULL;
697 return smu->of_dev;
698}
699
700EXPORT_SYMBOL_GPL(smu_get_ofdev);
701
702/*
703 * i2c interface
704 */
705
706static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
707{
708 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
709 void *misc = cmd->misc;
710 unsigned long flags;
711
712 /* Check for read case */
713 if (!fail && cmd->read) {
714 if (cmd->pdata[0] < 1)
715 fail = 1;
716 else
717 memcpy(cmd->info.data, &cmd->pdata[1],
718 cmd->info.datalen);
719 }
720
721 DPRINTK("SMU: completing, success: %d\n", !fail);
722
723 /* Update status and mark no pending i2c command with lock
724 * held so nobody comes in while we dequeue an eventual
725 * pending next i2c command
726 */
727 spin_lock_irqsave(&smu->lock, flags);
728 smu->cmd_i2c_cur = NULL;
729 wmb();
730 cmd->status = fail ? -EIO : 0;
731
732 /* Is there another i2c command waiting ? */
733 if (!list_empty(&smu->cmd_i2c_list)) {
734 struct smu_i2c_cmd *newcmd;
735
736 /* Fetch it, new current, remove from list */
737 newcmd = list_entry(smu->cmd_i2c_list.next,
738 struct smu_i2c_cmd, link);
739 smu->cmd_i2c_cur = newcmd;
740 list_del(&cmd->link);
741
742 /* Queue with low level smu */
743 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
744 if (smu->cmd_cur == NULL)
745 smu_start_cmd();
746 }
747 spin_unlock_irqrestore(&smu->lock, flags);
748
749 /* Call command completion handler if any */
750 if (done)
751 done(cmd, misc);
752
753}
754
755
756static void smu_i2c_retry(struct timer_list *unused)
757{
758 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur;
759
760 DPRINTK("SMU: i2c failure, requeuing...\n");
761
762 /* requeue command simply by resetting reply_len */
763 cmd->pdata[0] = 0xff;
764 cmd->scmd.reply_len = sizeof(cmd->pdata);
765 smu_queue_cmd(&cmd->scmd);
766}
767
768
769static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
770{
771 struct smu_i2c_cmd *cmd = misc;
772 int fail = 0;
773
774 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
775 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
776
777 /* Check for possible status */
778 if (scmd->status < 0)
779 fail = 1;
780 else if (cmd->read) {
781 if (cmd->stage == 0)
782 fail = cmd->pdata[0] != 0;
783 else
784 fail = cmd->pdata[0] >= 0x80;
785 } else {
786 fail = cmd->pdata[0] != 0;
787 }
788
789 /* Handle failures by requeuing command, after 5ms interval
790 */
791 if (fail && --cmd->retries > 0) {
792 DPRINTK("SMU: i2c failure, starting timer...\n");
793 BUG_ON(cmd != smu->cmd_i2c_cur);
794 if (!smu_irq_inited) {
795 mdelay(5);
796 smu_i2c_retry(NULL);
797 return;
798 }
799 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));
800 return;
801 }
802
803 /* If failure or stage 1, command is complete */
804 if (fail || cmd->stage != 0) {
805 smu_i2c_complete_command(cmd, fail);
806 return;
807 }
808
809 DPRINTK("SMU: going to stage 1\n");
810
811 /* Ok, initial command complete, now poll status */
812 scmd->reply_buf = cmd->pdata;
813 scmd->reply_len = sizeof(cmd->pdata);
814 scmd->data_buf = cmd->pdata;
815 scmd->data_len = 1;
816 cmd->pdata[0] = 0;
817 cmd->stage = 1;
818 cmd->retries = 20;
819 smu_queue_cmd(scmd);
820}
821
822
823int smu_queue_i2c(struct smu_i2c_cmd *cmd)
824{
825 unsigned long flags;
826
827 if (smu == NULL)
828 return -ENODEV;
829
830 /* Fill most fields of scmd */
831 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
832 cmd->scmd.done = smu_i2c_low_completion;
833 cmd->scmd.misc = cmd;
834 cmd->scmd.reply_buf = cmd->pdata;
835 cmd->scmd.reply_len = sizeof(cmd->pdata);
836 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
837 cmd->scmd.status = 1;
838 cmd->stage = 0;
839 cmd->pdata[0] = 0xff;
840 cmd->retries = 20;
841 cmd->status = 1;
842
843 /* Check transfer type, sanitize some "info" fields
844 * based on transfer type and do more checking
845 */
846 cmd->info.caddr = cmd->info.devaddr;
847 cmd->read = cmd->info.devaddr & 0x01;
848 switch(cmd->info.type) {
849 case SMU_I2C_TRANSFER_SIMPLE:
850 cmd->info.sublen = 0;
851 memset(cmd->info.subaddr, 0, sizeof(cmd->info.subaddr));
852 break;
853 case SMU_I2C_TRANSFER_COMBINED:
854 cmd->info.devaddr &= 0xfe;
855 fallthrough;
856 case SMU_I2C_TRANSFER_STDSUB:
857 if (cmd->info.sublen > 3)
858 return -EINVAL;
859 break;
860 default:
861 return -EINVAL;
862 }
863
864 /* Finish setting up command based on transfer direction
865 */
866 if (cmd->read) {
867 if (cmd->info.datalen > SMU_I2C_READ_MAX)
868 return -EINVAL;
869 memset(cmd->info.data, 0xff, cmd->info.datalen);
870 cmd->scmd.data_len = 9;
871 } else {
872 if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
873 return -EINVAL;
874 cmd->scmd.data_len = 9 + cmd->info.datalen;
875 }
876
877 DPRINTK("SMU: i2c enqueuing command\n");
878 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
879 cmd->read ? "read" : "write", cmd->info.datalen,
880 cmd->info.bus, cmd->info.caddr,
881 cmd->info.subaddr[0], cmd->info.type);
882
883
884 /* Enqueue command in i2c list, and if empty, enqueue also in
885 * main command list
886 */
887 spin_lock_irqsave(&smu->lock, flags);
888 if (smu->cmd_i2c_cur == NULL) {
889 smu->cmd_i2c_cur = cmd;
890 list_add_tail(&cmd->scmd.link, &smu->cmd_list);
891 if (smu->cmd_cur == NULL)
892 smu_start_cmd();
893 } else
894 list_add_tail(&cmd->link, &smu->cmd_i2c_list);
895 spin_unlock_irqrestore(&smu->lock, flags);
896
897 return 0;
898}
899
900/*
901 * Handling of "partitions"
902 */
903
904static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)
905{
906 DECLARE_COMPLETION_ONSTACK(comp);
907 unsigned int chunk;
908 struct smu_cmd cmd;
909 int rc;
910 u8 params[8];
911
912 /* We currently use a chunk size of 0xe. We could check the
913 * SMU firmware version and use bigger sizes though
914 */
915 chunk = 0xe;
916
917 while (len) {
918 unsigned int clen = min(len, chunk);
919
920 cmd.cmd = SMU_CMD_MISC_ee_COMMAND;
921 cmd.data_len = 7;
922 cmd.data_buf = params;
923 cmd.reply_len = chunk;
924 cmd.reply_buf = dest;
925 cmd.done = smu_done_complete;
926 cmd.misc = ∁
927 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;
928 params[1] = 0x4;
929 *((u32 *)¶ms[2]) = addr;
930 params[6] = clen;
931
932 rc = smu_queue_cmd(&cmd);
933 if (rc)
934 return rc;
935 wait_for_completion(&comp);
936 if (cmd.status != 0)
937 return rc;
938 if (cmd.reply_len != clen) {
939 printk(KERN_DEBUG "SMU: short read in "
940 "smu_read_datablock, got: %d, want: %d\n",
941 cmd.reply_len, clen);
942 return -EIO;
943 }
944 len -= clen;
945 addr += clen;
946 dest += clen;
947 }
948 return 0;
949}
950
951static struct smu_sdbp_header *smu_create_sdb_partition(int id)
952{
953 DECLARE_COMPLETION_ONSTACK(comp);
954 struct smu_simple_cmd cmd;
955 unsigned int addr, len, tlen;
956 struct smu_sdbp_header *hdr;
957 struct property *prop;
958
959 /* First query the partition info */
960 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);
961 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,
962 smu_done_complete, &comp,
963 SMU_CMD_PARTITION_LATEST, id);
964 wait_for_completion(&comp);
965 DPRINTK("SMU: done, status: %d, reply_len: %d\n",
966 cmd.cmd.status, cmd.cmd.reply_len);
967
968 /* Partition doesn't exist (or other error) */
969 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)
970 return NULL;
971
972 /* Fetch address and length from reply */
973 addr = *((u16 *)cmd.buffer);
974 len = cmd.buffer[3] << 2;
975 /* Calucluate total length to allocate, including the 17 bytes
976 * for "sdb-partition-XX" that we append at the end of the buffer
977 */
978 tlen = sizeof(struct property) + len + 18;
979
980 prop = kzalloc(tlen, GFP_KERNEL);
981 if (prop == NULL)
982 return NULL;
983 hdr = (struct smu_sdbp_header *)(prop + 1);
984 prop->name = ((char *)prop) + tlen - 18;
985 sprintf(prop->name, "sdb-partition-%02x", id);
986 prop->length = len;
987 prop->value = hdr;
988 prop->next = NULL;
989
990 /* Read the datablock */
991 if (smu_read_datablock((u8 *)hdr, addr, len)) {
992 printk(KERN_DEBUG "SMU: datablock read failed while reading "
993 "partition %02x !\n", id);
994 goto failure;
995 }
996
997 /* Got it, check a few things and create the property */
998 if (hdr->id != id) {
999 printk(KERN_DEBUG "SMU: Reading partition %02x and got "
1000 "%02x !\n", id, hdr->id);
1001 goto failure;
1002 }
1003 if (of_add_property(smu->of_node, prop)) {
1004 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "
1005 "property !\n", id);
1006 goto failure;
1007 }
1008
1009 return hdr;
1010 failure:
1011 kfree(prop);
1012 return NULL;
1013}
1014
1015/* Note: Only allowed to return error code in pointers (using ERR_PTR)
1016 * when interruptible is 1
1017 */
1018static const struct smu_sdbp_header *__smu_get_sdb_partition(int id,
1019 unsigned int *size, int interruptible)
1020{
1021 char pname[32];
1022 const struct smu_sdbp_header *part;
1023
1024 if (!smu)
1025 return NULL;
1026
1027 sprintf(pname, "sdb-partition-%02x", id);
1028
1029 DPRINTK("smu_get_sdb_partition(%02x)\n", id);
1030
1031 if (interruptible) {
1032 int rc;
1033 rc = mutex_lock_interruptible(&smu_part_access);
1034 if (rc)
1035 return ERR_PTR(rc);
1036 } else
1037 mutex_lock(&smu_part_access);
1038
1039 part = of_get_property(smu->of_node, pname, size);
1040 if (part == NULL) {
1041 DPRINTK("trying to extract from SMU ...\n");
1042 part = smu_create_sdb_partition(id);
1043 if (part != NULL && size)
1044 *size = part->len << 2;
1045 }
1046 mutex_unlock(&smu_part_access);
1047 return part;
1048}
1049
1050const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)
1051{
1052 return __smu_get_sdb_partition(id, size, 0);
1053}
1054EXPORT_SYMBOL(smu_get_sdb_partition);
1055
1056
1057/*
1058 * Userland driver interface
1059 */
1060
1061
1062static LIST_HEAD(smu_clist);
1063static DEFINE_SPINLOCK(smu_clist_lock);
1064
1065enum smu_file_mode {
1066 smu_file_commands,
1067 smu_file_events,
1068 smu_file_closing
1069};
1070
1071struct smu_private
1072{
1073 struct list_head list;
1074 enum smu_file_mode mode;
1075 int busy;
1076 struct smu_cmd cmd;
1077 spinlock_t lock;
1078 wait_queue_head_t wait;
1079 u8 buffer[SMU_MAX_DATA];
1080};
1081
1082
1083static int smu_open(struct inode *inode, struct file *file)
1084{
1085 struct smu_private *pp;
1086 unsigned long flags;
1087
1088 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL);
1089 if (!pp)
1090 return -ENOMEM;
1091 spin_lock_init(&pp->lock);
1092 pp->mode = smu_file_commands;
1093 init_waitqueue_head(&pp->wait);
1094
1095 mutex_lock(&smu_mutex);
1096 spin_lock_irqsave(&smu_clist_lock, flags);
1097 list_add(&pp->list, &smu_clist);
1098 spin_unlock_irqrestore(&smu_clist_lock, flags);
1099 file->private_data = pp;
1100 mutex_unlock(&smu_mutex);
1101
1102 return 0;
1103}
1104
1105
1106static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
1107{
1108 struct smu_private *pp = misc;
1109
1110 wake_up_all(&pp->wait);
1111}
1112
1113
1114static ssize_t smu_write(struct file *file, const char __user *buf,
1115 size_t count, loff_t *ppos)
1116{
1117 struct smu_private *pp = file->private_data;
1118 unsigned long flags;
1119 struct smu_user_cmd_hdr hdr;
1120 int rc = 0;
1121
1122 if (pp->busy)
1123 return -EBUSY;
1124 else if (copy_from_user(&hdr, buf, sizeof(hdr)))
1125 return -EFAULT;
1126 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
1127 pp->mode = smu_file_events;
1128 return 0;
1129 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {
1130 const struct smu_sdbp_header *part;
1131 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);
1132 if (part == NULL)
1133 return -EINVAL;
1134 else if (IS_ERR(part))
1135 return PTR_ERR(part);
1136 return 0;
1137 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
1138 return -EINVAL;
1139 else if (pp->mode != smu_file_commands)
1140 return -EBADFD;
1141 else if (hdr.data_len > SMU_MAX_DATA)
1142 return -EINVAL;
1143
1144 spin_lock_irqsave(&pp->lock, flags);
1145 if (pp->busy) {
1146 spin_unlock_irqrestore(&pp->lock, flags);
1147 return -EBUSY;
1148 }
1149 pp->busy = 1;
1150 pp->cmd.status = 1;
1151 spin_unlock_irqrestore(&pp->lock, flags);
1152
1153 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
1154 pp->busy = 0;
1155 return -EFAULT;
1156 }
1157
1158 pp->cmd.cmd = hdr.cmd;
1159 pp->cmd.data_len = hdr.data_len;
1160 pp->cmd.reply_len = SMU_MAX_DATA;
1161 pp->cmd.data_buf = pp->buffer;
1162 pp->cmd.reply_buf = pp->buffer;
1163 pp->cmd.done = smu_user_cmd_done;
1164 pp->cmd.misc = pp;
1165 rc = smu_queue_cmd(&pp->cmd);
1166 if (rc < 0)
1167 return rc;
1168 return count;
1169}
1170
1171
1172static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
1173 char __user *buf, size_t count)
1174{
1175 DECLARE_WAITQUEUE(wait, current);
1176 struct smu_user_reply_hdr hdr;
1177 unsigned long flags;
1178 int size, rc = 0;
1179
1180 if (!pp->busy)
1181 return 0;
1182 if (count < sizeof(struct smu_user_reply_hdr))
1183 return -EOVERFLOW;
1184 spin_lock_irqsave(&pp->lock, flags);
1185 if (pp->cmd.status == 1) {
1186 if (file->f_flags & O_NONBLOCK) {
1187 spin_unlock_irqrestore(&pp->lock, flags);
1188 return -EAGAIN;
1189 }
1190 add_wait_queue(&pp->wait, &wait);
1191 for (;;) {
1192 set_current_state(TASK_INTERRUPTIBLE);
1193 rc = 0;
1194 if (pp->cmd.status != 1)
1195 break;
1196 rc = -ERESTARTSYS;
1197 if (signal_pending(current))
1198 break;
1199 spin_unlock_irqrestore(&pp->lock, flags);
1200 schedule();
1201 spin_lock_irqsave(&pp->lock, flags);
1202 }
1203 set_current_state(TASK_RUNNING);
1204 remove_wait_queue(&pp->wait, &wait);
1205 }
1206 spin_unlock_irqrestore(&pp->lock, flags);
1207 if (rc)
1208 return rc;
1209 if (pp->cmd.status != 0)
1210 pp->cmd.reply_len = 0;
1211 size = sizeof(hdr) + pp->cmd.reply_len;
1212 if (count < size)
1213 size = count;
1214 rc = size;
1215 hdr.status = pp->cmd.status;
1216 hdr.reply_len = pp->cmd.reply_len;
1217 if (copy_to_user(buf, &hdr, sizeof(hdr)))
1218 return -EFAULT;
1219 size -= sizeof(hdr);
1220 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1221 return -EFAULT;
1222 pp->busy = 0;
1223
1224 return rc;
1225}
1226
1227
1228static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1229 char __user *buf, size_t count)
1230{
1231 /* Not implemented */
1232 msleep_interruptible(1000);
1233 return 0;
1234}
1235
1236
1237static ssize_t smu_read(struct file *file, char __user *buf,
1238 size_t count, loff_t *ppos)
1239{
1240 struct smu_private *pp = file->private_data;
1241
1242 if (pp->mode == smu_file_commands)
1243 return smu_read_command(file, pp, buf, count);
1244 if (pp->mode == smu_file_events)
1245 return smu_read_events(file, pp, buf, count);
1246
1247 return -EBADFD;
1248}
1249
1250static __poll_t smu_fpoll(struct file *file, poll_table *wait)
1251{
1252 struct smu_private *pp = file->private_data;
1253 __poll_t mask = 0;
1254 unsigned long flags;
1255
1256 if (!pp)
1257 return 0;
1258
1259 if (pp->mode == smu_file_commands) {
1260 poll_wait(file, &pp->wait, wait);
1261
1262 spin_lock_irqsave(&pp->lock, flags);
1263 if (pp->busy && pp->cmd.status != 1)
1264 mask |= EPOLLIN;
1265 spin_unlock_irqrestore(&pp->lock, flags);
1266 }
1267 if (pp->mode == smu_file_events) {
1268 /* Not yet implemented */
1269 }
1270 return mask;
1271}
1272
1273static int smu_release(struct inode *inode, struct file *file)
1274{
1275 struct smu_private *pp = file->private_data;
1276 unsigned long flags;
1277 unsigned int busy;
1278
1279 if (!pp)
1280 return 0;
1281
1282 file->private_data = NULL;
1283
1284 /* Mark file as closing to avoid races with new request */
1285 spin_lock_irqsave(&pp->lock, flags);
1286 pp->mode = smu_file_closing;
1287 busy = pp->busy;
1288
1289 /* Wait for any pending request to complete */
1290 if (busy && pp->cmd.status == 1) {
1291 DECLARE_WAITQUEUE(wait, current);
1292
1293 add_wait_queue(&pp->wait, &wait);
1294 for (;;) {
1295 set_current_state(TASK_UNINTERRUPTIBLE);
1296 if (pp->cmd.status != 1)
1297 break;
1298 spin_unlock_irqrestore(&pp->lock, flags);
1299 schedule();
1300 spin_lock_irqsave(&pp->lock, flags);
1301 }
1302 set_current_state(TASK_RUNNING);
1303 remove_wait_queue(&pp->wait, &wait);
1304 }
1305 spin_unlock_irqrestore(&pp->lock, flags);
1306
1307 spin_lock_irqsave(&smu_clist_lock, flags);
1308 list_del(&pp->list);
1309 spin_unlock_irqrestore(&smu_clist_lock, flags);
1310 kfree(pp);
1311
1312 return 0;
1313}
1314
1315
1316static const struct file_operations smu_device_fops = {
1317 .llseek = no_llseek,
1318 .read = smu_read,
1319 .write = smu_write,
1320 .poll = smu_fpoll,
1321 .open = smu_open,
1322 .release = smu_release,
1323};
1324
1325static struct miscdevice pmu_device = {
1326 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1327};
1328
1329static int smu_device_init(void)
1330{
1331 if (!smu)
1332 return -ENODEV;
1333 if (misc_register(&pmu_device) < 0)
1334 printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1335 return 0;
1336}
1337device_initcall(smu_device_init);