1 /*
2  * AHCI SATA platform library
3  *
4  * Copyright 2004-2005  Red Hat, Inc.
5  *   Jeff Garzik <jgarzik@pobox.com>
6  * Copyright 2010  MontaVista Software, LLC.
7  *   Anton Vorontsov <avorontsov@ru.mvista.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2, or (at your option)
12  * any later version.
13  */
14 
15 #include <linux/clk.h>
16 #include <linux/kernel.h>
17 #include <linux/gfp.h>
18 #include <linux/module.h>
19 #include <linux/pm.h>
20 #include <linux/interrupt.h>
21 #include <linux/device.h>
22 #include <linux/platform_device.h>
23 #include <linux/libata.h>
24 #include <linux/ahci_platform.h>
25 #include <linux/phy/phy.h>
26 #include <linux/pm_runtime.h>
27 #include "ahci.h"
28 
29 static void ahci_host_stop(struct ata_host *host);
30 
31 struct ata_port_operations ahci_platform_ops = {
32 	.inherits	= &ahci_ops,
33 	.host_stop	= ahci_host_stop,
34 };
35 EXPORT_SYMBOL_GPL(ahci_platform_ops);
36 
37 static struct scsi_host_template ahci_platform_sht = {
38 	AHCI_SHT("ahci_platform"),
39 };
40 
41 /**
42  * ahci_platform_enable_phys - Enable PHYs
43  * @hpriv: host private area to store config values
44  *
45  * This function enables all the PHYs found in hpriv->phys, if any.
46  * If a PHY fails to be enabled, it disables all the PHYs already
47  * enabled in reverse order and returns an error.
48  *
49  * RETURNS:
50  * 0 on success otherwise a negative error code
51  */
52 static int ahci_platform_enable_phys(struct ahci_host_priv *hpriv)
53 {
54 	int rc, i;
55 
56 	for (i = 0; i < hpriv->nports; i++) {
57 		if (!hpriv->phys[i])
58 			continue;
59 
60 		rc = phy_init(hpriv->phys[i]);
61 		if (rc)
62 			goto disable_phys;
63 
64 		rc = phy_power_on(hpriv->phys[i]);
65 		if (rc) {
66 			phy_exit(hpriv->phys[i]);
67 			goto disable_phys;
68 		}
69 	}
70 
71 	return 0;
72 
73 disable_phys:
74 	while (--i >= 0) {
75 		phy_power_off(hpriv->phys[i]);
76 		phy_exit(hpriv->phys[i]);
77 	}
78 	return rc;
79 }
80 
81 /**
82  * ahci_platform_disable_phys - Disable PHYs
83  * @hpriv: host private area to store config values
84  *
85  * This function disables all PHYs found in hpriv->phys.
86  */
87 static void ahci_platform_disable_phys(struct ahci_host_priv *hpriv)
88 {
89 	int i;
90 
91 	for (i = 0; i < hpriv->nports; i++) {
92 		if (!hpriv->phys[i])
93 			continue;
94 
95 		phy_power_off(hpriv->phys[i]);
96 		phy_exit(hpriv->phys[i]);
97 	}
98 }
99 
100 /**
101  * ahci_platform_enable_clks - Enable platform clocks
102  * @hpriv: host private area to store config values
103  *
104  * This function enables all the clks found in hpriv->clks, starting at
105  * index 0. If any clk fails to enable it disables all the clks already
106  * enabled in reverse order, and then returns an error.
107  *
108  * RETURNS:
109  * 0 on success otherwise a negative error code
110  */
111 int ahci_platform_enable_clks(struct ahci_host_priv *hpriv)
112 {
113 	int c, rc;
114 
115 	for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++) {
116 		rc = clk_prepare_enable(hpriv->clks[c]);
117 		if (rc)
118 			goto disable_unprepare_clk;
119 	}
120 	return 0;
121 
122 disable_unprepare_clk:
123 	while (--c >= 0)
124 		clk_disable_unprepare(hpriv->clks[c]);
125 	return rc;
126 }
127 EXPORT_SYMBOL_GPL(ahci_platform_enable_clks);
128 
129 /**
130  * ahci_platform_disable_clks - Disable platform clocks
131  * @hpriv: host private area to store config values
132  *
133  * This function disables all the clks found in hpriv->clks, in reverse
134  * order of ahci_platform_enable_clks (starting at the end of the array).
135  */
136 void ahci_platform_disable_clks(struct ahci_host_priv *hpriv)
137 {
138 	int c;
139 
140 	for (c = AHCI_MAX_CLKS - 1; c >= 0; c--)
141 		if (hpriv->clks[c])
142 			clk_disable_unprepare(hpriv->clks[c]);
143 }
144 EXPORT_SYMBOL_GPL(ahci_platform_disable_clks);
145 
146 /**
147  * ahci_platform_enable_resources - Enable platform resources
148  * @hpriv: host private area to store config values
149  *
150  * This function enables all ahci_platform managed resources in the
151  * following order:
152  * 1) Regulator
153  * 2) Clocks (through ahci_platform_enable_clks)
154  * 3) Phys
155  *
156  * If resource enabling fails at any point the previous enabled resources
157  * are disabled in reverse order.
158  *
159  * RETURNS:
160  * 0 on success otherwise a negative error code
161  */
162 int ahci_platform_enable_resources(struct ahci_host_priv *hpriv)
163 {
164 	int rc;
165 
166 	if (hpriv->target_pwr) {
167 		rc = regulator_enable(hpriv->target_pwr);
168 		if (rc)
169 			return rc;
170 	}
171 
172 	rc = ahci_platform_enable_clks(hpriv);
173 	if (rc)
174 		goto disable_regulator;
175 
176 	rc = ahci_platform_enable_phys(hpriv);
177 	if (rc)
178 		goto disable_clks;
179 
180 	return 0;
181 
182 disable_clks:
183 	ahci_platform_disable_clks(hpriv);
184 
185 disable_regulator:
186 	if (hpriv->target_pwr)
187 		regulator_disable(hpriv->target_pwr);
188 	return rc;
189 }
190 EXPORT_SYMBOL_GPL(ahci_platform_enable_resources);
191 
192 /**
193  * ahci_platform_disable_resources - Disable platform resources
194  * @hpriv: host private area to store config values
195  *
196  * This function disables all ahci_platform managed resources in the
197  * following order:
198  * 1) Phys
199  * 2) Clocks (through ahci_platform_disable_clks)
200  * 3) Regulator
201  */
202 void ahci_platform_disable_resources(struct ahci_host_priv *hpriv)
203 {
204 	ahci_platform_disable_phys(hpriv);
205 
206 	ahci_platform_disable_clks(hpriv);
207 
208 	if (hpriv->target_pwr)
209 		regulator_disable(hpriv->target_pwr);
210 }
211 EXPORT_SYMBOL_GPL(ahci_platform_disable_resources);
212 
213 static void ahci_platform_put_resources(struct device *dev, void *res)
214 {
215 	struct ahci_host_priv *hpriv = res;
216 	int c;
217 
218 	if (hpriv->got_runtime_pm) {
219 		pm_runtime_put_sync(dev);
220 		pm_runtime_disable(dev);
221 	}
222 
223 	for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
224 		clk_put(hpriv->clks[c]);
225 }
226 
227 /**
228  * ahci_platform_get_resources - Get platform resources
229  * @pdev: platform device to get resources for
230  *
231  * This function allocates an ahci_host_priv struct, and gets the following
232  * resources, storing a reference to them inside the returned struct:
233  *
234  * 1) mmio registers (IORESOURCE_MEM 0, mandatory)
235  * 2) regulator for controlling the targets power (optional)
236  * 3) 0 - AHCI_MAX_CLKS clocks, as specified in the devs devicetree node,
237  *    or for non devicetree enabled platforms a single clock
238  *	4) phys (optional)
239  *
240  * RETURNS:
241  * The allocated ahci_host_priv on success, otherwise an ERR_PTR value
242  */
243 struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev)
244 {
245 	struct device *dev = &pdev->dev;
246 	struct ahci_host_priv *hpriv;
247 	struct clk *clk;
248 	struct device_node *child;
249 	int i, enabled_ports = 0, rc = -ENOMEM;
250 	u32 mask_port_map = 0;
251 
252 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
253 		return ERR_PTR(-ENOMEM);
254 
255 	hpriv = devres_alloc(ahci_platform_put_resources, sizeof(*hpriv),
256 			     GFP_KERNEL);
257 	if (!hpriv)
258 		goto err_out;
259 
260 	devres_add(dev, hpriv);
261 
262 	hpriv->mmio = devm_ioremap_resource(dev,
263 			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
264 	if (IS_ERR(hpriv->mmio)) {
265 		dev_err(dev, "no mmio space\n");
266 		rc = PTR_ERR(hpriv->mmio);
267 		goto err_out;
268 	}
269 
270 	hpriv->target_pwr = devm_regulator_get_optional(dev, "target");
271 	if (IS_ERR(hpriv->target_pwr)) {
272 		rc = PTR_ERR(hpriv->target_pwr);
273 		if (rc == -EPROBE_DEFER)
274 			goto err_out;
275 		hpriv->target_pwr = NULL;
276 	}
277 
278 	for (i = 0; i < AHCI_MAX_CLKS; i++) {
279 		/*
280 		 * For now we must use clk_get(dev, NULL) for the first clock,
281 		 * because some platforms (da850, spear13xx) are not yet
282 		 * converted to use devicetree for clocks.  For new platforms
283 		 * this is equivalent to of_clk_get(dev->of_node, 0).
284 		 */
285 		if (i == 0)
286 			clk = clk_get(dev, NULL);
287 		else
288 			clk = of_clk_get(dev->of_node, i);
289 
290 		if (IS_ERR(clk)) {
291 			rc = PTR_ERR(clk);
292 			if (rc == -EPROBE_DEFER)
293 				goto err_out;
294 			break;
295 		}
296 		hpriv->clks[i] = clk;
297 	}
298 
299 	hpriv->nports = of_get_child_count(dev->of_node);
300 
301 	if (hpriv->nports) {
302 		hpriv->phys = devm_kzalloc(dev,
303 					   hpriv->nports * sizeof(*hpriv->phys),
304 					   GFP_KERNEL);
305 		if (!hpriv->phys) {
306 			rc = -ENOMEM;
307 			goto err_out;
308 		}
309 
310 		for_each_child_of_node(dev->of_node, child) {
311 			u32 port;
312 
313 			if (!of_device_is_available(child))
314 				continue;
315 
316 			if (of_property_read_u32(child, "reg", &port)) {
317 				rc = -EINVAL;
318 				goto err_out;
319 			}
320 
321 			if (port >= hpriv->nports) {
322 				dev_warn(dev, "invalid port number %d\n", port);
323 				continue;
324 			}
325 
326 			mask_port_map |= BIT(port);
327 
328 			hpriv->phys[port] = devm_of_phy_get(dev, child, NULL);
329 			if (IS_ERR(hpriv->phys[port])) {
330 				rc = PTR_ERR(hpriv->phys[port]);
331 				dev_err(dev,
332 					"couldn't get PHY in node %s: %d\n",
333 					child->name, rc);
334 				goto err_out;
335 			}
336 
337 			enabled_ports++;
338 		}
339 		if (!enabled_ports) {
340 			dev_warn(dev, "No port enabled\n");
341 			rc = -ENODEV;
342 			goto err_out;
343 		}
344 
345 		if (!hpriv->mask_port_map)
346 			hpriv->mask_port_map = mask_port_map;
347 	} else {
348 		/*
349 		 * If no sub-node was found, keep this for device tree
350 		 * compatibility
351 		 */
352 		struct phy *phy = devm_phy_get(dev, "sata-phy");
353 		if (!IS_ERR(phy)) {
354 			hpriv->phys = devm_kzalloc(dev, sizeof(*hpriv->phys),
355 						   GFP_KERNEL);
356 			if (!hpriv->phys) {
357 				rc = -ENOMEM;
358 				goto err_out;
359 			}
360 
361 			hpriv->phys[0] = phy;
362 			hpriv->nports = 1;
363 		} else {
364 			rc = PTR_ERR(phy);
365 			switch (rc) {
366 				case -ENOSYS:
367 					/* No PHY support. Check if PHY is required. */
368 					if (of_find_property(dev->of_node, "phys", NULL)) {
369 						dev_err(dev, "couldn't get sata-phy: ENOSYS\n");
370 						goto err_out;
371 					}
372 				case -ENODEV:
373 					/* continue normally */
374 					hpriv->phys = NULL;
375 					break;
376 
377 				default:
378 					goto err_out;
379 
380 			}
381 		}
382 	}
383 
384 	pm_runtime_enable(dev);
385 	pm_runtime_get_sync(dev);
386 	hpriv->got_runtime_pm = true;
387 
388 	devres_remove_group(dev, NULL);
389 	return hpriv;
390 
391 err_out:
392 	devres_release_group(dev, NULL);
393 	return ERR_PTR(rc);
394 }
395 EXPORT_SYMBOL_GPL(ahci_platform_get_resources);
396 
397 /**
398  * ahci_platform_init_host - Bring up an ahci-platform host
399  * @pdev: platform device pointer for the host
400  * @hpriv: ahci-host private data for the host
401  * @pi_template: template for the ata_port_info to use
402  *
403  * This function does all the usual steps needed to bring up an
404  * ahci-platform host, note any necessary resources (ie clks, phys, etc.)
405  * must be initialized / enabled before calling this.
406  *
407  * RETURNS:
408  * 0 on success otherwise a negative error code
409  */
410 int ahci_platform_init_host(struct platform_device *pdev,
411 			    struct ahci_host_priv *hpriv,
412 			    const struct ata_port_info *pi_template)
413 {
414 	struct device *dev = &pdev->dev;
415 	struct ata_port_info pi = *pi_template;
416 	const struct ata_port_info *ppi[] = { &pi, NULL };
417 	struct ata_host *host;
418 	int i, irq, n_ports, rc;
419 
420 	irq = platform_get_irq(pdev, 0);
421 	if (irq <= 0) {
422 		dev_err(dev, "no irq\n");
423 		return -EINVAL;
424 	}
425 
426 	/* prepare host */
427 	pi.private_data = (void *)(unsigned long)hpriv->flags;
428 
429 	ahci_save_initial_config(dev, hpriv);
430 
431 	if (hpriv->cap & HOST_CAP_NCQ)
432 		pi.flags |= ATA_FLAG_NCQ;
433 
434 	if (hpriv->cap & HOST_CAP_PMP)
435 		pi.flags |= ATA_FLAG_PMP;
436 
437 	ahci_set_em_messages(hpriv, &pi);
438 
439 	/* CAP.NP sometimes indicate the index of the last enabled
440 	 * port, at other times, that of the last possible port, so
441 	 * determining the maximum port number requires looking at
442 	 * both CAP.NP and port_map.
443 	 */
444 	n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
445 
446 	host = ata_host_alloc_pinfo(dev, ppi, n_ports);
447 	if (!host)
448 		return -ENOMEM;
449 
450 	host->private_data = hpriv;
451 
452 	if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
453 		host->flags |= ATA_HOST_PARALLEL_SCAN;
454 	else
455 		dev_info(dev, "SSS flag set, parallel bus scan disabled\n");
456 
457 	if (pi.flags & ATA_FLAG_EM)
458 		ahci_reset_em(host);
459 
460 	for (i = 0; i < host->n_ports; i++) {
461 		struct ata_port *ap = host->ports[i];
462 
463 		ata_port_desc(ap, "mmio %pR",
464 			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
465 		ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
466 
467 		/* set enclosure management message type */
468 		if (ap->flags & ATA_FLAG_EM)
469 			ap->em_message_type = hpriv->em_msg_type;
470 
471 		/* disabled/not-implemented port */
472 		if (!(hpriv->port_map & (1 << i)))
473 			ap->ops = &ata_dummy_port_ops;
474 	}
475 
476 	if (hpriv->cap & HOST_CAP_64) {
477 		rc = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(64));
478 		if (rc) {
479 			rc = dma_coerce_mask_and_coherent(dev,
480 							  DMA_BIT_MASK(32));
481 			if (rc) {
482 				dev_err(dev, "Failed to enable 64-bit DMA.\n");
483 				return rc;
484 			}
485 			dev_warn(dev, "Enable 32-bit DMA instead of 64-bit.\n");
486 		}
487 	}
488 
489 	rc = ahci_reset_controller(host);
490 	if (rc)
491 		return rc;
492 
493 	ahci_init_controller(host);
494 	ahci_print_info(host, "platform");
495 
496 	return ahci_host_activate(host, irq, &ahci_platform_sht);
497 }
498 EXPORT_SYMBOL_GPL(ahci_platform_init_host);
499 
500 static void ahci_host_stop(struct ata_host *host)
501 {
502 	struct ahci_host_priv *hpriv = host->private_data;
503 
504 	ahci_platform_disable_resources(hpriv);
505 }
506 
507 #ifdef CONFIG_PM_SLEEP
508 /**
509  * ahci_platform_suspend_host - Suspend an ahci-platform host
510  * @dev: device pointer for the host
511  *
512  * This function does all the usual steps needed to suspend an
513  * ahci-platform host, note any necessary resources (ie clks, phys, etc.)
514  * must be disabled after calling this.
515  *
516  * RETURNS:
517  * 0 on success otherwise a negative error code
518  */
519 int ahci_platform_suspend_host(struct device *dev)
520 {
521 	struct ata_host *host = dev_get_drvdata(dev);
522 	struct ahci_host_priv *hpriv = host->private_data;
523 	void __iomem *mmio = hpriv->mmio;
524 	u32 ctl;
525 
526 	if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
527 		dev_err(dev, "firmware update required for suspend/resume\n");
528 		return -EIO;
529 	}
530 
531 	/*
532 	 * AHCI spec rev1.1 section 8.3.3:
533 	 * Software must disable interrupts prior to requesting a
534 	 * transition of the HBA to D3 state.
535 	 */
536 	ctl = readl(mmio + HOST_CTL);
537 	ctl &= ~HOST_IRQ_EN;
538 	writel(ctl, mmio + HOST_CTL);
539 	readl(mmio + HOST_CTL); /* flush */
540 
541 	return ata_host_suspend(host, PMSG_SUSPEND);
542 }
543 EXPORT_SYMBOL_GPL(ahci_platform_suspend_host);
544 
545 /**
546  * ahci_platform_resume_host - Resume an ahci-platform host
547  * @dev: device pointer for the host
548  *
549  * This function does all the usual steps needed to resume an ahci-platform
550  * host, note any necessary resources (ie clks, phys, etc.)  must be
551  * initialized / enabled before calling this.
552  *
553  * RETURNS:
554  * 0 on success otherwise a negative error code
555  */
556 int ahci_platform_resume_host(struct device *dev)
557 {
558 	struct ata_host *host = dev_get_drvdata(dev);
559 	int rc;
560 
561 	if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
562 		rc = ahci_reset_controller(host);
563 		if (rc)
564 			return rc;
565 
566 		ahci_init_controller(host);
567 	}
568 
569 	ata_host_resume(host);
570 
571 	return 0;
572 }
573 EXPORT_SYMBOL_GPL(ahci_platform_resume_host);
574 
575 /**
576  * ahci_platform_suspend - Suspend an ahci-platform device
577  * @dev: the platform device to suspend
578  *
579  * This function suspends the host associated with the device, followed by
580  * disabling all the resources of the device.
581  *
582  * RETURNS:
583  * 0 on success otherwise a negative error code
584  */
585 int ahci_platform_suspend(struct device *dev)
586 {
587 	struct ata_host *host = dev_get_drvdata(dev);
588 	struct ahci_host_priv *hpriv = host->private_data;
589 	int rc;
590 
591 	rc = ahci_platform_suspend_host(dev);
592 	if (rc)
593 		return rc;
594 
595 	ahci_platform_disable_resources(hpriv);
596 
597 	return 0;
598 }
599 EXPORT_SYMBOL_GPL(ahci_platform_suspend);
600 
601 /**
602  * ahci_platform_resume - Resume an ahci-platform device
603  * @dev: the platform device to resume
604  *
605  * This function enables all the resources of the device followed by
606  * resuming the host associated with the device.
607  *
608  * RETURNS:
609  * 0 on success otherwise a negative error code
610  */
611 int ahci_platform_resume(struct device *dev)
612 {
613 	struct ata_host *host = dev_get_drvdata(dev);
614 	struct ahci_host_priv *hpriv = host->private_data;
615 	int rc;
616 
617 	rc = ahci_platform_enable_resources(hpriv);
618 	if (rc)
619 		return rc;
620 
621 	rc = ahci_platform_resume_host(dev);
622 	if (rc)
623 		goto disable_resources;
624 
625 	/* We resumed so update PM runtime state */
626 	pm_runtime_disable(dev);
627 	pm_runtime_set_active(dev);
628 	pm_runtime_enable(dev);
629 
630 	return 0;
631 
632 disable_resources:
633 	ahci_platform_disable_resources(hpriv);
634 
635 	return rc;
636 }
637 EXPORT_SYMBOL_GPL(ahci_platform_resume);
638 #endif
639 
640 MODULE_DESCRIPTION("AHCI SATA platform library");
641 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
642 MODULE_LICENSE("GPL");
643