write in 30M

hc

2024-02-20 ea08eeccae9297f7aabd2ef7f0c2517ac4549acc

 kernel/drivers/cpufreq/brcmstb-avs-cpufreq.c
..
..
@@ -42,6 +42,7 @@
42
42
  */
43
43
 
44
44
 #include <linux/cpufreq.h>
45
+#include <linux/delay.h>
45
46
 #include <linux/interrupt.h>
46
47
 #include <linux/io.h>
47
48
 #include <linux/module.h>
..
..
@@ -178,6 +179,7 @@
178
179
 	struct completion done;
179
180
 	struct semaphore sem;
180
181
 	struct pmap pmap;
182
+	int host_irq;
181
183
 };
182
184
 
183
185
 static void __iomem *__map_region(const char *name)
..
..
@@ -195,11 +197,36 @@
195
197
 	return ptr;
196
198
 }
197
199
 
198
-static int __issue_avs_command(struct private_data *priv, int cmd, bool is_send,
200
+static unsigned long wait_for_avs_command(struct private_data *priv,
201
+					  unsigned long timeout)
202
+{
203
+	unsigned long time_left = 0;
204
+	u32 val;
205
+
206
+	/* Event driven, wait for the command interrupt */
207
+	if (priv->host_irq >= 0)
208
+		return wait_for_completion_timeout(&priv->done,
209
+						   msecs_to_jiffies(timeout));
210
+
211
+	/* Polling for command completion */
212
+	do {
213
+		time_left = timeout;
214
+		val = readl(priv->base + AVS_MBOX_STATUS);
215
+		if (val)
216
+			break;
217
+
218
+		usleep_range(1000, 2000);
219
+	} while (--timeout);
220
+
221
+	return time_left;
222
+}
223
+
224
+static int __issue_avs_command(struct private_data *priv, unsigned int cmd,
225
+			       unsigned int num_in, unsigned int num_out,
199
226
 			       u32 args[])
200
227
 {
201
-	unsigned long time_left = msecs_to_jiffies(AVS_TIMEOUT);
202
228
 	void __iomem *base = priv->base;
229
+	unsigned long time_left;
203
230
 	unsigned int i;
204
231
 	int ret;
205
232
 	u32 val;
..
..
@@ -225,11 +252,9 @@
225
252
 	/* Clear status before we begin. */
226
253
 	writel(AVS_STATUS_CLEAR, base + AVS_MBOX_STATUS);
227
254
 
228
-	/* We need to send arguments for this command. */
229
-	if (args && is_send) {
230
-		for (i = 0; i < AVS_MAX_CMD_ARGS; i++)
231
-			writel(args[i], base + AVS_MBOX_PARAM(i));
232
-	}
255
+	/* Provide input parameters */
256
+	for (i = 0; i < num_in; i++)
257
+		writel(args[i], base + AVS_MBOX_PARAM(i));
233
258
 
234
259
 	/* Protect from spurious interrupts. */
235
260
 	reinit_completion(&priv->done);
..
..
@@ -239,7 +264,7 @@
239
264
 	writel(AVS_CPU_L2_INT_MASK, priv->avs_intr_base + AVS_CPU_L2_SET0);
240
265
 
241
266
 	/* Wait for AVS co-processor to finish processing the command. */
242
-	time_left = wait_for_completion_timeout(&priv->done, time_left);
267
+	time_left = wait_for_avs_command(priv, AVS_TIMEOUT);
243
268
 
244
269
 	/*
245
270
 	 * If the AVS status is not in the expected range, it means AVS didn't
..
..
@@ -256,11 +281,9 @@
256
281
 		goto out;
257
282
 	}
258
283
 
259
-	/* This command returned arguments, so we read them back. */
260
-	if (args && !is_send) {
261
-		for (i = 0; i < AVS_MAX_CMD_ARGS; i++)
262
-			args[i] = readl(base + AVS_MBOX_PARAM(i));
263
-	}
284
+	/* Process returned values */
285
+	for (i = 0; i < num_out; i++)
286
+		args[i] = readl(base + AVS_MBOX_PARAM(i));
264
287
 
265
288
 	/* Clear status to tell AVS co-processor we are done. */
266
289
 	writel(AVS_STATUS_CLEAR, base + AVS_MBOX_STATUS);
..
..
@@ -338,7 +361,7 @@
338
361
 	u32 args[AVS_MAX_CMD_ARGS];
339
362
 	int ret;
340
363
 
341
-	ret = __issue_avs_command(priv, AVS_CMD_GET_PMAP, false, args);
364
+	ret = __issue_avs_command(priv, AVS_CMD_GET_PMAP, 0, 4, args);
342
365
 	if (ret || !pmap)
343
366
 		return ret;
344
367
 
..
..
@@ -359,7 +382,7 @@
359
382
 	args[2] = pmap->p2;
360
383
 	args[3] = pmap->state;
361
384
 
362
-	return __issue_avs_command(priv, AVS_CMD_SET_PMAP, true, args);
385
+	return __issue_avs_command(priv, AVS_CMD_SET_PMAP, 4, 0, args);
363
386
 }
364
387
 
365
388
 static int brcm_avs_get_pstate(struct private_data *priv, unsigned int *pstate)
..
..
@@ -367,7 +390,7 @@
367
390
 	u32 args[AVS_MAX_CMD_ARGS];
368
391
 	int ret;
369
392
 
370
-	ret = __issue_avs_command(priv, AVS_CMD_GET_PSTATE, false, args);
393
+	ret = __issue_avs_command(priv, AVS_CMD_GET_PSTATE, 0, 1, args);
371
394
 	if (ret)
372
395
 		return ret;
373
396
 	*pstate = args[0];
..
..
@@ -381,7 +404,8 @@
381
404
 
382
405
 	args[0] = pstate;
383
406
 
384
-	return __issue_avs_command(priv, AVS_CMD_SET_PSTATE, true, args);
407
+	return __issue_avs_command(priv, AVS_CMD_SET_PSTATE, 1, 0, args);
408
+
385
409
 }
386
410
 
387
411
 static u32 brcm_avs_get_voltage(void __iomem *base)
..
..
@@ -410,7 +434,11 @@
410
434
 	if (ret)
411
435
 		return ERR_PTR(ret);
412
436
 
413
-	table = devm_kcalloc(dev, AVS_PSTATE_MAX + 1, sizeof(*table),
437
+	/*
438
+	 * We allocate space for the 5 different P-STATES AVS,
439
+	 * plus extra space for a terminating element.
440
+	 */
441
+	table = devm_kcalloc(dev, AVS_PSTATE_MAX + 1 + 1, sizeof(*table),
414
442
 			     GFP_KERNEL);
415
443
 	if (!table)
416
444
 		return ERR_PTR(-ENOMEM);
..
..
@@ -455,6 +483,8 @@
455
483
 	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
456
484
 	struct private_data *priv = policy->driver_data;
457
485
 
486
+	cpufreq_cpu_put(policy);
487
+
458
488
 	return brcm_avs_get_frequency(priv->base);
459
489
 }
460
490
 
..
..
@@ -480,13 +510,23 @@
480
510
 	 * AVS co-processor, not necessarily the P-state we are running at now.
481
511
 	 * So, we get the current P-state explicitly.
482
512
 	 */
483
-	return brcm_avs_get_pstate(priv, &priv->pmap.state);
513
+	ret = brcm_avs_get_pstate(priv, &priv->pmap.state);
514
+	if (ret)
515
+		return ret;
516
+
517
+	/* This is best effort. Nothing to do if it fails. */
518
+	(void)__issue_avs_command(priv, AVS_CMD_S2_ENTER, 0, 0, NULL);
519
+
520
+	return 0;
484
521
 }
485
522
 
486
523
 static int brcm_avs_resume(struct cpufreq_policy *policy)
487
524
 {
488
525
 	struct private_data *priv = policy->driver_data;
489
526
 	int ret;
527
+
528
+	/* This is best effort. Nothing to do if it fails. */
529
+	(void)__issue_avs_command(priv, AVS_CMD_S2_EXIT, 0, 0, NULL);
490
530
 
491
531
 	ret = brcm_avs_set_pmap(priv, &priv->pmap);
492
532
 	if (ret == -EEXIST) {
..
..
@@ -509,7 +549,7 @@
509
549
 {
510
550
 	struct private_data *priv;
511
551
 	struct device *dev;
512
-	int host_irq, ret;
552
+	int ret;
513
553
 
514
554
 	dev = &pdev->dev;
515
555
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
..
..
@@ -536,19 +576,14 @@
536
576
 		goto unmap_base;
537
577
 	}
538
578
 
539
-	host_irq = platform_get_irq_byname(pdev, BRCM_AVS_HOST_INTR);
540
-	if (host_irq < 0) {
541
-		dev_err(dev, "Couldn't find interrupt %s -- %d\n",
542
-			BRCM_AVS_HOST_INTR, host_irq);
543
-		ret = host_irq;
544
-		goto unmap_intr_base;
545
-	}
579
+	priv->host_irq = platform_get_irq_byname(pdev, BRCM_AVS_HOST_INTR);
546
580
 
547
-	ret = devm_request_irq(dev, host_irq, irq_handler, IRQF_TRIGGER_RISING,
581
+	ret = devm_request_irq(dev, priv->host_irq, irq_handler,
582
+			       IRQF_TRIGGER_RISING,
548
583
 			       BRCM_AVS_HOST_INTR, priv);
549
-	if (ret) {
584
+	if (ret && priv->host_irq >= 0) {
550
585
 		dev_err(dev, "IRQ request failed: %s (%d) -- %d\n",
551
-			BRCM_AVS_HOST_INTR, host_irq, ret);
586
+			BRCM_AVS_HOST_INTR, priv->host_irq, ret);
552
587
 		goto unmap_intr_base;
553
588
 	}
554
589
 
..
..
@@ -601,7 +636,7 @@
601
636
 	/* All cores share the same clock and thus the same policy. */
602
637
 	cpumask_setall(policy->cpus);
603
638
 
604
-	ret = __issue_avs_command(priv, AVS_CMD_ENABLE, false, NULL);
639
+	ret = __issue_avs_command(priv, AVS_CMD_ENABLE, 0, 0, NULL);
605
640
 	if (!ret) {
606
641
 		unsigned int pstate;
607
642