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mm: vmstats: tlb flush counters
[linux-2.6.git] / drivers / macintosh / rack-meter.c
blobcad0e19b47a285eb4b96ae9d9869f640f26e064e
1 /*
2 * RackMac vu-meter driver
3 *
4 * (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp.
5 * <benh@kernel.crashing.org>
6 *
7 * Released under the term of the GNU GPL v2.
8 *
9 * Support the CPU-meter LEDs of the Xserve G5
10 *
11 * TODO: Implement PWM to do variable intensity and provide userland
12 * interface for fun. Also, the CPU-meter could be made nicer by being
13 * a bit less "immediate" but giving instead a more average load over
14 * time. Patches welcome :-)
15 *
16 */
17 #undef DEBUG
18
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
22 #include <linux/device.h>
23 #include <linux/interrupt.h>
24 #include <linux/module.h>
25 #include <linux/pci.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/kernel_stat.h>
28
29 #include <asm/io.h>
30 #include <asm/prom.h>
31 #include <asm/machdep.h>
32 #include <asm/pmac_feature.h>
33 #include <asm/dbdma.h>
34 #include <asm/macio.h>
35 #include <asm/keylargo.h>
36
37 /* Number of samples in a sample buffer */
38 #define SAMPLE_COUNT 256
39
40 /* CPU meter sampling rate in ms */
41 #define CPU_SAMPLING_RATE 250
42
43 struct rackmeter_dma {
44 struct dbdma_cmd cmd[4] ____cacheline_aligned;
45 u32 mark ____cacheline_aligned;
46 u32 buf1[SAMPLE_COUNT] ____cacheline_aligned;
47 u32 buf2[SAMPLE_COUNT] ____cacheline_aligned;
48 } ____cacheline_aligned;
49
50 struct rackmeter_cpu {
51 struct delayed_work sniffer;
52 struct rackmeter *rm;
53 cputime64_t prev_wall;
54 cputime64_t prev_idle;
55 int zero;
56 } ____cacheline_aligned;
57
58 struct rackmeter {
59 struct macio_dev *mdev;
60 unsigned int irq;
61 struct device_node *i2s;
62 u8 *ubuf;
63 struct dbdma_regs __iomem *dma_regs;
64 void __iomem *i2s_regs;
65 dma_addr_t dma_buf_p;
66 struct rackmeter_dma *dma_buf_v;
67 int stale_irq;
68 struct rackmeter_cpu cpu[2];
69 int paused;
70 struct mutex sem;
71 };
72
73 /* To be set as a tunable */
74 static int rackmeter_ignore_nice;
75
76 /* This GPIO is whacked by the OS X driver when initializing */
77 #define RACKMETER_MAGIC_GPIO 0x78
78
79 /* This is copied from cpufreq_ondemand, maybe we should put it in
80 * a common header somewhere
81 */
82 static inline cputime64_t get_cpu_idle_time(unsigned int cpu)
83 {
84 u64 retval;
85
86 retval = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE] +
87 kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
88
89 if (rackmeter_ignore_nice)
90 retval += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE];
91
92 return retval;
93 }
94
95 static void rackmeter_setup_i2s(struct rackmeter *rm)
96 {
97 struct macio_chip *macio = rm->mdev->bus->chip;
98
99 /* First whack magic GPIO */
100 pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, RACKMETER_MAGIC_GPIO, 5);
101
102
103 /* Call feature code to enable the sound channel and the proper
104 * clock sources
105 */
106 pmac_call_feature(PMAC_FTR_SOUND_CHIP_ENABLE, rm->i2s, 0, 1);
107
108 /* Power i2s and stop i2s clock. We whack MacIO FCRs directly for now.
109 * This is a bit racy, thus we should add new platform functions to
110 * handle that. snd-aoa needs that too
111 */
112 MACIO_BIS(KEYLARGO_FCR1, KL1_I2S0_ENABLE);
113 MACIO_BIC(KEYLARGO_FCR1, KL1_I2S0_CLK_ENABLE_BIT);
114 (void)MACIO_IN32(KEYLARGO_FCR1);
115 udelay(10);
116
117 /* Then setup i2s. For now, we use the same magic value that
118 * the OS X driver seems to use. We might want to play around
119 * with the clock divisors later
120 */
121 out_le32(rm->i2s_regs + 0x10, 0x01fa0000);
122 (void)in_le32(rm->i2s_regs + 0x10);
123 udelay(10);
124
125 /* Fully restart i2s*/
126 MACIO_BIS(KEYLARGO_FCR1, KL1_I2S0_CELL_ENABLE |
127 KL1_I2S0_CLK_ENABLE_BIT);
128 (void)MACIO_IN32(KEYLARGO_FCR1);
129 udelay(10);
130 }
131
132 static void rackmeter_set_default_pattern(struct rackmeter *rm)
133 {
134 int i;
135
136 for (i = 0; i < 16; i++) {
137 if (i < 8)
138 rm->ubuf[i] = (i & 1) * 255;
139 else
140 rm->ubuf[i] = ((~i) & 1) * 255;
141 }
142 }
143
144 static void rackmeter_do_pause(struct rackmeter *rm, int pause)
145 {
146 struct rackmeter_dma *rdma = rm->dma_buf_v;
147
148 pr_debug("rackmeter: %s\n", pause ? "paused" : "started");
149
150 rm->paused = pause;
151 if (pause) {
152 DBDMA_DO_STOP(rm->dma_regs);
153 return;
154 }
155 memset(rdma->buf1, 0, SAMPLE_COUNT & sizeof(u32));
156 memset(rdma->buf2, 0, SAMPLE_COUNT & sizeof(u32));
157
158 rm->dma_buf_v->mark = 0;
159
160 mb();
161 out_le32(&rm->dma_regs->cmdptr_hi, 0);
162 out_le32(&rm->dma_regs->cmdptr, rm->dma_buf_p);
163 out_le32(&rm->dma_regs->control, (RUN << 16) | RUN);
164 }
165
166 static void rackmeter_setup_dbdma(struct rackmeter *rm)
167 {
168 struct rackmeter_dma *db = rm->dma_buf_v;
169 struct dbdma_cmd *cmd = db->cmd;
170
171 /* Make sure dbdma is reset */
172 DBDMA_DO_RESET(rm->dma_regs);
173
174 pr_debug("rackmeter: mark offset=0x%zx\n",
175 offsetof(struct rackmeter_dma, mark));
176 pr_debug("rackmeter: buf1 offset=0x%zx\n",
177 offsetof(struct rackmeter_dma, buf1));
178 pr_debug("rackmeter: buf2 offset=0x%zx\n",
179 offsetof(struct rackmeter_dma, buf2));
180
181 /* Prepare 4 dbdma commands for the 2 buffers */
182 memset(cmd, 0, 4 * sizeof(struct dbdma_cmd));
183 st_le16(&cmd->req_count, 4);
184 st_le16(&cmd->command, STORE_WORD | INTR_ALWAYS | KEY_SYSTEM);
185 st_le32(&cmd->phy_addr, rm->dma_buf_p +
186 offsetof(struct rackmeter_dma, mark));
187 st_le32(&cmd->cmd_dep, 0x02000000);
188 cmd++;
189
190 st_le16(&cmd->req_count, SAMPLE_COUNT * 4);
191 st_le16(&cmd->command, OUTPUT_MORE);
192 st_le32(&cmd->phy_addr, rm->dma_buf_p +
193 offsetof(struct rackmeter_dma, buf1));
194 cmd++;
195
196 st_le16(&cmd->req_count, 4);
197 st_le16(&cmd->command, STORE_WORD | INTR_ALWAYS | KEY_SYSTEM);
198 st_le32(&cmd->phy_addr, rm->dma_buf_p +
199 offsetof(struct rackmeter_dma, mark));
200 st_le32(&cmd->cmd_dep, 0x01000000);
201 cmd++;
202
203 st_le16(&cmd->req_count, SAMPLE_COUNT * 4);
204 st_le16(&cmd->command, OUTPUT_MORE | BR_ALWAYS);
205 st_le32(&cmd->phy_addr, rm->dma_buf_p +
206 offsetof(struct rackmeter_dma, buf2));
207 st_le32(&cmd->cmd_dep, rm->dma_buf_p);
208
209 rackmeter_do_pause(rm, 0);
210 }
211
212 static void rackmeter_do_timer(struct work_struct *work)
213 {
214 struct rackmeter_cpu *rcpu =
215 container_of(work, struct rackmeter_cpu, sniffer.work);
216 struct rackmeter *rm = rcpu->rm;
217 unsigned int cpu = smp_processor_id();
218 cputime64_t cur_jiffies, total_idle_ticks;
219 unsigned int total_ticks, idle_ticks;
220 int i, offset, load, cumm, pause;
221
222 cur_jiffies = jiffies64_to_cputime64(get_jiffies_64());
223 total_ticks = (unsigned int) (cur_jiffies - rcpu->prev_wall);
224 rcpu->prev_wall = cur_jiffies;
225
226 total_idle_ticks = get_cpu_idle_time(cpu);
227 idle_ticks = (unsigned int) (total_idle_ticks - rcpu->prev_idle);
228 rcpu->prev_idle = total_idle_ticks;
229
230 /* We do a very dumb calculation to update the LEDs for now,
231 * we'll do better once we have actual PWM implemented
232 */
233 load = (9 * (total_ticks - idle_ticks)) / total_ticks;
234
235 offset = cpu << 3;
236 cumm = 0;
237 for (i = 0; i < 8; i++) {
238 u8 ub = (load > i) ? 0xff : 0;
239 rm->ubuf[i + offset] = ub;
240 cumm |= ub;
241 }
242 rcpu->zero = (cumm == 0);
243
244 /* Now check if LEDs are all 0, we can stop DMA */
245 pause = (rm->cpu[0].zero && rm->cpu[1].zero);
246 if (pause != rm->paused) {
247 mutex_lock(&rm->sem);
248 pause = (rm->cpu[0].zero && rm->cpu[1].zero);
249 rackmeter_do_pause(rm, pause);
250 mutex_unlock(&rm->sem);
251 }
252 schedule_delayed_work_on(cpu, &rcpu->sniffer,
253 msecs_to_jiffies(CPU_SAMPLING_RATE));
254 }
255
256 static void rackmeter_init_cpu_sniffer(struct rackmeter *rm)
257 {
258 unsigned int cpu;
259
260 /* This driver works only with 1 or 2 CPUs numbered 0 and 1,
261 * but that's really all we have on Apple Xserve. It doesn't
262 * play very nice with CPU hotplug neither but we don't do that
263 * on those machines yet
264 */
265
266 rm->cpu[0].rm = rm;
267 INIT_DELAYED_WORK(&rm->cpu[0].sniffer, rackmeter_do_timer);
268 rm->cpu[1].rm = rm;
269 INIT_DELAYED_WORK(&rm->cpu[1].sniffer, rackmeter_do_timer);
270
271 for_each_online_cpu(cpu) {
272 struct rackmeter_cpu *rcpu;
273
274 if (cpu > 1)
275 continue;
276 rcpu = &rm->cpu[cpu];
277 rcpu->prev_idle = get_cpu_idle_time(cpu);
278 rcpu->prev_wall = jiffies64_to_cputime64(get_jiffies_64());
279 schedule_delayed_work_on(cpu, &rm->cpu[cpu].sniffer,
280 msecs_to_jiffies(CPU_SAMPLING_RATE));
281 }
282 }
283
284 static void rackmeter_stop_cpu_sniffer(struct rackmeter *rm)
285 {
286 cancel_delayed_work_sync(&rm->cpu[0].sniffer);
287 cancel_delayed_work_sync(&rm->cpu[1].sniffer);
288 }
289
290 static int rackmeter_setup(struct rackmeter *rm)
291 {
292 pr_debug("rackmeter: setting up i2s..\n");
293 rackmeter_setup_i2s(rm);
294
295 pr_debug("rackmeter: setting up default pattern..\n");
296 rackmeter_set_default_pattern(rm);
297
298 pr_debug("rackmeter: setting up dbdma..\n");
299 rackmeter_setup_dbdma(rm);
300
301 pr_debug("rackmeter: start CPU measurements..\n");
302 rackmeter_init_cpu_sniffer(rm);
303
304 printk(KERN_INFO "RackMeter initialized\n");
305
306 return 0;
307 }
308
309 /* XXX FIXME: No PWM yet, this is 0/1 */
310 static u32 rackmeter_calc_sample(struct rackmeter *rm, unsigned int index)
311 {
312 int led;
313 u32 sample = 0;
314
315 for (led = 0; led < 16; led++) {
316 sample >>= 1;
317 sample |= ((rm->ubuf[led] >= 0x80) << 15);
318 }
319 return (sample << 17) | (sample >> 15);
320 }
321
322 static irqreturn_t rackmeter_irq(int irq, void *arg)
323 {
324 struct rackmeter *rm = arg;
325 struct rackmeter_dma *db = rm->dma_buf_v;
326 unsigned int mark, i;
327 u32 *buf;
328
329 /* Flush PCI buffers with an MMIO read. Maybe we could actually
330 * check the status one day ... in case things go wrong, though
331 * this never happened to me
332 */
333 (void)in_le32(&rm->dma_regs->status);
334
335 /* Make sure the CPU gets us in order */
336 rmb();
337
338 /* Read mark */
339 mark = db->mark;
340 if (mark != 1 && mark != 2) {
341 printk(KERN_WARNING "rackmeter: Incorrect DMA mark 0x%08x\n",
342 mark);
343 /* We allow for 3 errors like that (stale DBDMA irqs) */
344 if (++rm->stale_irq > 3) {
345 printk(KERN_ERR "rackmeter: Too many errors,"
346 " stopping DMA\n");
347 DBDMA_DO_RESET(rm->dma_regs);
348 }
349 return IRQ_HANDLED;
350 }
351
352 /* Next buffer we need to fill is mark value */
353 buf = mark == 1 ? db->buf1 : db->buf2;
354
355 /* Fill it now. This routine converts the 8 bits depth sample array
356 * into the PWM bitmap for each LED.
357 */
358 for (i = 0; i < SAMPLE_COUNT; i++)
359 buf[i] = rackmeter_calc_sample(rm, i);
360
361
362 return IRQ_HANDLED;
363 }
364
365 static int rackmeter_probe(struct macio_dev* mdev,
366 const struct of_device_id *match)
367 {
368 struct device_node *i2s = NULL, *np = NULL;
369 struct rackmeter *rm = NULL;
370 struct resource ri2s, rdma;
371 int rc = -ENODEV;
372
373 pr_debug("rackmeter_probe()\n");
374
375 /* Get i2s-a node */
376 while ((i2s = of_get_next_child(mdev->ofdev.dev.of_node, i2s)) != NULL)
377 if (strcmp(i2s->name, "i2s-a") == 0)
378 break;
379 if (i2s == NULL) {
380 pr_debug(" i2s-a child not found\n");
381 goto bail;
382 }
383 /* Get lightshow or virtual sound */
384 while ((np = of_get_next_child(i2s, np)) != NULL) {
385 if (strcmp(np->name, "lightshow") == 0)
386 break;
387 if ((strcmp(np->name, "sound") == 0) &&
388 of_get_property(np, "virtual", NULL) != NULL)
389 break;
390 }
391 if (np == NULL) {
392 pr_debug(" lightshow or sound+virtual child not found\n");
393 goto bail;
394 }
395
396 /* Create and initialize our instance data */
397 rm = kzalloc(sizeof(struct rackmeter), GFP_KERNEL);
398 if (rm == NULL) {
399 printk(KERN_ERR "rackmeter: failed to allocate memory !\n");
400 rc = -ENOMEM;
401 goto bail_release;
402 }
403 rm->mdev = mdev;
404 rm->i2s = i2s;
405 mutex_init(&rm->sem);
406 dev_set_drvdata(&mdev->ofdev.dev, rm);
407 /* Check resources availability. We need at least resource 0 and 1 */
408 #if 0 /* Use that when i2s-a is finally an mdev per-se */
409 if (macio_resource_count(mdev) < 2 || macio_irq_count(mdev) < 2) {
410 printk(KERN_ERR
411 "rackmeter: found match but lacks resources: %s"
412 " (%d resources, %d interrupts)\n",
413 mdev->ofdev.node->full_name);
414 rc = -ENXIO;
415 goto bail_free;
416 }
417 if (macio_request_resources(mdev, "rackmeter")) {
418 printk(KERN_ERR
419 "rackmeter: failed to request resources: %s\n",
420 mdev->ofdev.node->full_name);
421 rc = -EBUSY;
422 goto bail_free;
423 }
424 rm->irq = macio_irq(mdev, 1);
425 #else
426 rm->irq = irq_of_parse_and_map(i2s, 1);
427 if (rm->irq == NO_IRQ ||
428 of_address_to_resource(i2s, 0, &ri2s) ||
429 of_address_to_resource(i2s, 1, &rdma)) {
430 printk(KERN_ERR
431 "rackmeter: found match but lacks resources: %s",
432 mdev->ofdev.dev.of_node->full_name);
433 rc = -ENXIO;
434 goto bail_free;
435 }
436 #endif
437
438 pr_debug(" i2s @0x%08x\n", (unsigned int)ri2s.start);
439 pr_debug(" dma @0x%08x\n", (unsigned int)rdma.start);
440 pr_debug(" irq %d\n", rm->irq);
441
442 rm->ubuf = (u8 *)__get_free_page(GFP_KERNEL);
443 if (rm->ubuf == NULL) {
444 printk(KERN_ERR
445 "rackmeter: failed to allocate samples page !\n");
446 rc = -ENOMEM;
447 goto bail_release;
448 }
449
450 rm->dma_buf_v = dma_alloc_coherent(&macio_get_pci_dev(mdev)->dev,
451 sizeof(struct rackmeter_dma),
452 &rm->dma_buf_p, GFP_KERNEL);
453 if (rm->dma_buf_v == NULL) {
454 printk(KERN_ERR
455 "rackmeter: failed to allocate dma buffer !\n");
456 rc = -ENOMEM;
457 goto bail_free_samples;
458 }
459 #if 0
460 rm->i2s_regs = ioremap(macio_resource_start(mdev, 0), 0x1000);
461 #else
462 rm->i2s_regs = ioremap(ri2s.start, 0x1000);
463 #endif
464 if (rm->i2s_regs == NULL) {
465 printk(KERN_ERR
466 "rackmeter: failed to map i2s registers !\n");
467 rc = -ENXIO;
468 goto bail_free_dma;
469 }
470 #if 0
471 rm->dma_regs = ioremap(macio_resource_start(mdev, 1), 0x100);
472 #else
473 rm->dma_regs = ioremap(rdma.start, 0x100);
474 #endif
475 if (rm->dma_regs == NULL) {
476 printk(KERN_ERR
477 "rackmeter: failed to map dma registers !\n");
478 rc = -ENXIO;
479 goto bail_unmap_i2s;
480 }
481
482 rc = rackmeter_setup(rm);
483 if (rc) {
484 printk(KERN_ERR
485 "rackmeter: failed to initialize !\n");
486 rc = -ENXIO;
487 goto bail_unmap_dma;
488 }
489
490 rc = request_irq(rm->irq, rackmeter_irq, 0, "rackmeter", rm);
491 if (rc != 0) {
492 printk(KERN_ERR
493 "rackmeter: failed to request interrupt !\n");
494 goto bail_stop_dma;
495 }
496 of_node_put(np);
497 return 0;
498
499 bail_stop_dma:
500 DBDMA_DO_RESET(rm->dma_regs);
501 bail_unmap_dma:
502 iounmap(rm->dma_regs);
503 bail_unmap_i2s:
504 iounmap(rm->i2s_regs);
505 bail_free_dma:
506 dma_free_coherent(&macio_get_pci_dev(mdev)->dev,
507 sizeof(struct rackmeter_dma),
508 rm->dma_buf_v, rm->dma_buf_p);
509 bail_free_samples:
510 free_page((unsigned long)rm->ubuf);
511 bail_release:
512 #if 0
513 macio_release_resources(mdev);
514 #endif
515 bail_free:
516 kfree(rm);
517 bail:
518 of_node_put(i2s);
519 of_node_put(np);
520 dev_set_drvdata(&mdev->ofdev.dev, NULL);
521 return rc;
522 }
523
524 static int rackmeter_remove(struct macio_dev* mdev)
525 {
526 struct rackmeter *rm = dev_get_drvdata(&mdev->ofdev.dev);
527
528 /* Stop CPU sniffer timer & work queues */
529 rackmeter_stop_cpu_sniffer(rm);
530
531 /* Clear reference to private data */
532 dev_set_drvdata(&mdev->ofdev.dev, NULL);
533
534 /* Stop/reset dbdma */
535 DBDMA_DO_RESET(rm->dma_regs);
536
537 /* Release the IRQ */
538 free_irq(rm->irq, rm);
539
540 /* Unmap registers */
541 iounmap(rm->dma_regs);
542 iounmap(rm->i2s_regs);
543
544 /* Free DMA */
545 dma_free_coherent(&macio_get_pci_dev(mdev)->dev,
546 sizeof(struct rackmeter_dma),
547 rm->dma_buf_v, rm->dma_buf_p);
548
549 /* Free samples */
550 free_page((unsigned long)rm->ubuf);
551
552 #if 0
553 /* Release resources */
554 macio_release_resources(mdev);
555 #endif
556
557 /* Get rid of me */
558 kfree(rm);
559
560 return 0;
561 }
562
563 static int rackmeter_shutdown(struct macio_dev* mdev)
564 {
565 struct rackmeter *rm = dev_get_drvdata(&mdev->ofdev.dev);
566
567 if (rm == NULL)
568 return -ENODEV;
569
570 /* Stop CPU sniffer timer & work queues */
571 rackmeter_stop_cpu_sniffer(rm);
572
573 /* Stop/reset dbdma */
574 DBDMA_DO_RESET(rm->dma_regs);
575
576 return 0;
577 }
578
579 static struct of_device_id rackmeter_match[] = {
580 { .name = "i2s" },
581 { }
582 };
583
584 static struct macio_driver rackmeter_driver = {
585 .driver = {
586 .name = "rackmeter",
587 .owner = THIS_MODULE,
588 .of_match_table = rackmeter_match,
589 },
590 .probe = rackmeter_probe,
591 .remove = rackmeter_remove,
592 .shutdown = rackmeter_shutdown,
593 };
594
595
596 static int __init rackmeter_init(void)
597 {
598 pr_debug("rackmeter_init()\n");
599
600 return macio_register_driver(&rackmeter_driver);
601 }
602
603 static void __exit rackmeter_exit(void)
604 {
605 pr_debug("rackmeter_exit()\n");
606
607 macio_unregister_driver(&rackmeter_driver);
608 }
609
610 module_init(rackmeter_init);
611 module_exit(rackmeter_exit);
612
613
614 MODULE_LICENSE("GPL");
615 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
616 MODULE_DESCRIPTION("RackMeter: Support vu-meter on XServe front panel");
Linus' kernel tree