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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/sysdev.h>
36#include <linux/poll.h>
37#include <linux/mutex.h>
38#include <linux/of_device.h>
39#include <linux/of_platform.h>
40#include <linux/slab.h>
41
42#include <asm/byteorder.h>
43#include <asm/io.h>
44#include <asm/prom.h>
45#include <asm/machdep.h>
46#include <asm/pmac_feature.h>
47#include <asm/smu.h>
48#include <asm/sections.h>
49#include <asm/abs_addr.h>
50#include <asm/uaccess.h>
51
52#define VERSION "0.7"
53#define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
54
55#undef DEBUG_SMU
56
57#ifdef DEBUG_SMU
58#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
59#else
60#define DPRINTK(fmt, args...) do { } while (0)
61#endif
62
63/*
64 * This is the command buffer passed to the SMU hardware
65 */
66#define SMU_MAX_DATA 254
67
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;
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 /* Workaround for early calls when irq isn't available */
285 if (!smu_irq_inited || smu->db_irq == NO_IRQ)
286 smu_spinwait_cmd(cmd);
287
288 return 0;
289}
290EXPORT_SYMBOL(smu_queue_cmd);
291
292
293int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
294 unsigned int data_len,
295 void (*done)(struct smu_cmd *cmd, void *misc),
296 void *misc, ...)
297{
298 struct smu_cmd *cmd = &scmd->cmd;
299 va_list list;
300 int i;
301
302 if (data_len > sizeof(scmd->buffer))
303 return -EINVAL;
304
305 memset(scmd, 0, sizeof(*scmd));
306 cmd->cmd = command;
307 cmd->data_len = data_len;
308 cmd->data_buf = scmd->buffer;
309 cmd->reply_len = sizeof(scmd->buffer);
310 cmd->reply_buf = scmd->buffer;
311 cmd->done = done;
312 cmd->misc = misc;
313
314 va_start(list, misc);
315 for (i = 0; i < data_len; ++i)
316 scmd->buffer[i] = (u8)va_arg(list, int);
317 va_end(list);
318
319 return smu_queue_cmd(cmd);
320}
321EXPORT_SYMBOL(smu_queue_simple);
322
323
324void smu_poll(void)
325{
326 u8 gpio;
327
328 if (smu == NULL)
329 return;
330
331 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
332 if ((gpio & 7) == 7)
333 smu_db_intr(smu->db_irq, smu);
334}
335EXPORT_SYMBOL(smu_poll);
336
337
338void smu_done_complete(struct smu_cmd *cmd, void *misc)
339{
340 struct completion *comp = misc;
341
342 complete(comp);
343}
344EXPORT_SYMBOL(smu_done_complete);
345
346
347void smu_spinwait_cmd(struct smu_cmd *cmd)
348{
349 while(cmd->status == 1)
350 smu_poll();
351}
352EXPORT_SYMBOL(smu_spinwait_cmd);
353
354
355/* RTC low level commands */
356static inline int bcd2hex (int n)
357{
358 return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
359}
360
361
362static inline int hex2bcd (int n)
363{
364 return ((n / 10) << 4) + (n % 10);
365}
366
367
368static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
369 struct rtc_time *time)
370{
371 cmd_buf->cmd = 0x8e;
372 cmd_buf->length = 8;
373 cmd_buf->data[0] = 0x80;
374 cmd_buf->data[1] = hex2bcd(time->tm_sec);
375 cmd_buf->data[2] = hex2bcd(time->tm_min);
376 cmd_buf->data[3] = hex2bcd(time->tm_hour);
377 cmd_buf->data[4] = time->tm_wday;
378 cmd_buf->data[5] = hex2bcd(time->tm_mday);
379 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
380 cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
381}
382
383
384int smu_get_rtc_time(struct rtc_time *time, int spinwait)
385{
386 struct smu_simple_cmd cmd;
387 int rc;
388
389 if (smu == NULL)
390 return -ENODEV;
391
392 memset(time, 0, sizeof(struct rtc_time));
393 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
394 SMU_CMD_RTC_GET_DATETIME);
395 if (rc)
396 return rc;
397 smu_spinwait_simple(&cmd);
398
399 time->tm_sec = bcd2hex(cmd.buffer[0]);
400 time->tm_min = bcd2hex(cmd.buffer[1]);
401 time->tm_hour = bcd2hex(cmd.buffer[2]);
402 time->tm_wday = bcd2hex(cmd.buffer[3]);
403 time->tm_mday = bcd2hex(cmd.buffer[4]);
404 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
405 time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
406
407 return 0;
408}
409
410
411int smu_set_rtc_time(struct rtc_time *time, int spinwait)
412{
413 struct smu_simple_cmd cmd;
414 int rc;
415
416 if (smu == NULL)
417 return -ENODEV;
418
419 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
420 SMU_CMD_RTC_SET_DATETIME,
421 hex2bcd(time->tm_sec),
422 hex2bcd(time->tm_min),
423 hex2bcd(time->tm_hour),
424 time->tm_wday,
425 hex2bcd(time->tm_mday),
426 hex2bcd(time->tm_mon) + 1,
427 hex2bcd(time->tm_year - 100));
428 if (rc)
429 return rc;
430 smu_spinwait_simple(&cmd);
431
432 return 0;
433}
434
435
436void smu_shutdown(void)
437{
438 struct smu_simple_cmd cmd;
439
440 if (smu == NULL)
441 return;
442
443 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
444 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
445 return;
446 smu_spinwait_simple(&cmd);
447 for (;;)
448 ;
449}
450
451
452void smu_restart(void)
453{
454 struct smu_simple_cmd cmd;
455
456 if (smu == NULL)
457 return;
458
459 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
460 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
461 return;
462 smu_spinwait_simple(&cmd);
463 for (;;)
464 ;
465}
466
467
468int smu_present(void)
469{
470 return smu != NULL;
471}
472EXPORT_SYMBOL(smu_present);
473
474
475int __init smu_init (void)
476{
477 struct device_node *np;
478 const u32 *data;
479 int ret = 0;
480
481 np = of_find_node_by_type(NULL, "smu");
482 if (np == NULL)
483 return -ENODEV;
484
485 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
486
487 if (smu_cmdbuf_abs == 0) {
488 printk(KERN_ERR "SMU: Command buffer not allocated !\n");
489 ret = -EINVAL;
490 goto fail_np;
491 }
492
493 smu = alloc_bootmem(sizeof(struct smu_device));
494
495 spin_lock_init(&smu->lock);
496 INIT_LIST_HEAD(&smu->cmd_list);
497 INIT_LIST_HEAD(&smu->cmd_i2c_list);
498 smu->of_node = np;
499 smu->db_irq = NO_IRQ;
500 smu->msg_irq = NO_IRQ;
501
502 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
503 * 32 bits value safely
504 */
505 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
506 smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs);
507
508 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
509 if (smu->db_node == NULL) {
510 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
511 ret = -ENXIO;
512 goto fail_bootmem;
513 }
514 data = of_get_property(smu->db_node, "reg", NULL);
515 if (data == NULL) {
516 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
517 ret = -ENXIO;
518 goto fail_db_node;
519 }
520
521 /* Current setup has one doorbell GPIO that does both doorbell
522 * and ack. GPIOs are at 0x50, best would be to find that out
523 * in the device-tree though.
524 */
525 smu->doorbell = *data;
526 if (smu->doorbell < 0x50)
527 smu->doorbell += 0x50;
528
529 /* Now look for the smu-interrupt GPIO */
530 do {
531 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
532 if (smu->msg_node == NULL)
533 break;
534 data = of_get_property(smu->msg_node, "reg", NULL);
535 if (data == NULL) {
536 of_node_put(smu->msg_node);
537 smu->msg_node = NULL;
538 break;
539 }
540 smu->msg = *data;
541 if (smu->msg < 0x50)
542 smu->msg += 0x50;
543 } while(0);
544
545 /* Doorbell buffer is currently hard-coded, I didn't find a proper
546 * device-tree entry giving the address. Best would probably to use
547 * an offset for K2 base though, but let's do it that way for now.
548 */
549 smu->db_buf = ioremap(0x8000860c, 0x1000);
550 if (smu->db_buf == NULL) {
551 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
552 ret = -ENXIO;
553 goto fail_msg_node;
554 }
555
556 /* U3 has an issue with NAP mode when issuing SMU commands */
557 smu->broken_nap = pmac_get_uninorth_variant() < 4;
558 if (smu->broken_nap)
559 printk(KERN_INFO "SMU: using NAP mode workaround\n");
560
561 sys_ctrler = SYS_CTRLER_SMU;
562 return 0;
563
564fail_msg_node:
565 if (smu->msg_node)
566 of_node_put(smu->msg_node);
567fail_db_node:
568 of_node_put(smu->db_node);
569fail_bootmem:
570 free_bootmem((unsigned long)smu, sizeof(struct smu_device));
571 smu = NULL;
572fail_np:
573 of_node_put(np);
574 return ret;
575}
576
577
578static int smu_late_init(void)
579{
580 if (!smu)
581 return 0;
582
583 init_timer(&smu->i2c_timer);
584 smu->i2c_timer.function = smu_i2c_retry;
585 smu->i2c_timer.data = (unsigned long)smu;
586
587 if (smu->db_node) {
588 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
589 if (smu->db_irq == NO_IRQ)
590 printk(KERN_ERR "smu: failed to map irq for node %s\n",
591 smu->db_node->full_name);
592 }
593 if (smu->msg_node) {
594 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
595 if (smu->msg_irq == NO_IRQ)
596 printk(KERN_ERR "smu: failed to map irq for node %s\n",
597 smu->msg_node->full_name);
598 }
599
600 /*
601 * Try to request the interrupts
602 */
603
604 if (smu->db_irq != NO_IRQ) {
605 if (request_irq(smu->db_irq, smu_db_intr,
606 IRQF_SHARED, "SMU doorbell", smu) < 0) {
607 printk(KERN_WARNING "SMU: can't "
608 "request interrupt %d\n",
609 smu->db_irq);
610 smu->db_irq = NO_IRQ;
611 }
612 }
613
614 if (smu->msg_irq != NO_IRQ) {
615 if (request_irq(smu->msg_irq, smu_msg_intr,
616 IRQF_SHARED, "SMU message", smu) < 0) {
617 printk(KERN_WARNING "SMU: can't "
618 "request interrupt %d\n",
619 smu->msg_irq);
620 smu->msg_irq = NO_IRQ;
621 }
622 }
623
624 smu_irq_inited = 1;
625 return 0;
626}
627/* This has to be before arch_initcall as the low i2c stuff relies on the
628 * above having been done before we reach arch_initcalls
629 */
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 (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;)
641 if (of_device_is_compatible(np, "smu-sensors"))
642 of_platform_device_create(np, "smu-sensors",
643 &smu->of_dev->dev);
644}
645
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 .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 platform_driver_register(&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 mutex_lock(&smu_mutex);
1098 spin_lock_irqsave(&smu_clist_lock, flags);
1099 list_add(&pp->list, &smu_clist);
1100 spin_unlock_irqrestore(&smu_clist_lock, flags);
1101 file->private_data = pp;
1102 mutex_unlock(&smu_mutex);
1103
1104 return 0;
1105}
1106
1107
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);
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);