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_clks - Enable platform clocks
43  * @hpriv: host private area to store config values
44  *
45  * This function enables all the clks found in hpriv->clks, starting at
46  * index 0. If any clk fails to enable it disables all the clks already
47  * enabled in reverse order, and then returns an error.
48  *
49  * RETURNS:
50  * 0 on success otherwise a negative error code
51  */
52 int ahci_platform_enable_clks(struct ahci_host_priv *hpriv)
53 {
54 	int c, rc;
55 
56 	for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++) {
57 		rc = clk_prepare_enable(hpriv->clks[c]);
58 		if (rc)
59 			goto disable_unprepare_clk;
60 	}
61 	return 0;
62 
63 disable_unprepare_clk:
64 	while (--c >= 0)
65 		clk_disable_unprepare(hpriv->clks[c]);
66 	return rc;
67 }
68 EXPORT_SYMBOL_GPL(ahci_platform_enable_clks);
69 
70 /**
71  * ahci_platform_disable_clks - Disable platform clocks
72  * @hpriv: host private area to store config values
73  *
74  * This function disables all the clks found in hpriv->clks, in reverse
75  * order of ahci_platform_enable_clks (starting at the end of the array).
76  */
77 void ahci_platform_disable_clks(struct ahci_host_priv *hpriv)
78 {
79 	int c;
80 
81 	for (c = AHCI_MAX_CLKS - 1; c >= 0; c--)
82 		if (hpriv->clks[c])
83 			clk_disable_unprepare(hpriv->clks[c]);
84 }
85 EXPORT_SYMBOL_GPL(ahci_platform_disable_clks);
86 
87 /**
88  * ahci_platform_enable_resources - Enable platform resources
89  * @hpriv: host private area to store config values
90  *
91  * This function enables all ahci_platform managed resources in the
92  * following order:
93  * 1) Regulator
94  * 2) Clocks (through ahci_platform_enable_clks)
95  * 3) Phy
96  *
97  * If resource enabling fails at any point the previous enabled resources
98  * are disabled in reverse order.
99  *
100  * RETURNS:
101  * 0 on success otherwise a negative error code
102  */
103 int ahci_platform_enable_resources(struct ahci_host_priv *hpriv)
104 {
105 	int rc;
106 
107 	if (hpriv->target_pwr) {
108 		rc = regulator_enable(hpriv->target_pwr);
109 		if (rc)
110 			return rc;
111 	}
112 
113 	rc = ahci_platform_enable_clks(hpriv);
114 	if (rc)
115 		goto disable_regulator;
116 
117 	if (hpriv->phy) {
118 		rc = phy_init(hpriv->phy);
119 		if (rc)
120 			goto disable_clks;
121 
122 		rc = phy_power_on(hpriv->phy);
123 		if (rc) {
124 			phy_exit(hpriv->phy);
125 			goto disable_clks;
126 		}
127 	}
128 
129 	return 0;
130 
131 disable_clks:
132 	ahci_platform_disable_clks(hpriv);
133 
134 disable_regulator:
135 	if (hpriv->target_pwr)
136 		regulator_disable(hpriv->target_pwr);
137 	return rc;
138 }
139 EXPORT_SYMBOL_GPL(ahci_platform_enable_resources);
140 
141 /**
142  * ahci_platform_disable_resources - Disable platform resources
143  * @hpriv: host private area to store config values
144  *
145  * This function disables all ahci_platform managed resources in the
146  * following order:
147  * 1) Phy
148  * 2) Clocks (through ahci_platform_disable_clks)
149  * 3) Regulator
150  */
151 void ahci_platform_disable_resources(struct ahci_host_priv *hpriv)
152 {
153 	if (hpriv->phy) {
154 		phy_power_off(hpriv->phy);
155 		phy_exit(hpriv->phy);
156 	}
157 
158 	ahci_platform_disable_clks(hpriv);
159 
160 	if (hpriv->target_pwr)
161 		regulator_disable(hpriv->target_pwr);
162 }
163 EXPORT_SYMBOL_GPL(ahci_platform_disable_resources);
164 
165 static void ahci_platform_put_resources(struct device *dev, void *res)
166 {
167 	struct ahci_host_priv *hpriv = res;
168 	int c;
169 
170 	if (hpriv->got_runtime_pm) {
171 		pm_runtime_put_sync(dev);
172 		pm_runtime_disable(dev);
173 	}
174 
175 	for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
176 		clk_put(hpriv->clks[c]);
177 }
178 
179 /**
180  * ahci_platform_get_resources - Get platform resources
181  * @pdev: platform device to get resources for
182  *
183  * This function allocates an ahci_host_priv struct, and gets the following
184  * resources, storing a reference to them inside the returned struct:
185  *
186  * 1) mmio registers (IORESOURCE_MEM 0, mandatory)
187  * 2) regulator for controlling the targets power (optional)
188  * 3) 0 - AHCI_MAX_CLKS clocks, as specified in the devs devicetree node,
189  *    or for non devicetree enabled platforms a single clock
190  *	4) phy (optional)
191  *
192  * RETURNS:
193  * The allocated ahci_host_priv on success, otherwise an ERR_PTR value
194  */
195 struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev)
196 {
197 	struct device *dev = &pdev->dev;
198 	struct ahci_host_priv *hpriv;
199 	struct clk *clk;
200 	int i, rc = -ENOMEM;
201 
202 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
203 		return ERR_PTR(-ENOMEM);
204 
205 	hpriv = devres_alloc(ahci_platform_put_resources, sizeof(*hpriv),
206 			     GFP_KERNEL);
207 	if (!hpriv)
208 		goto err_out;
209 
210 	devres_add(dev, hpriv);
211 
212 	hpriv->mmio = devm_ioremap_resource(dev,
213 			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
214 	if (IS_ERR(hpriv->mmio)) {
215 		dev_err(dev, "no mmio space\n");
216 		rc = PTR_ERR(hpriv->mmio);
217 		goto err_out;
218 	}
219 
220 	hpriv->target_pwr = devm_regulator_get_optional(dev, "target");
221 	if (IS_ERR(hpriv->target_pwr)) {
222 		rc = PTR_ERR(hpriv->target_pwr);
223 		if (rc == -EPROBE_DEFER)
224 			goto err_out;
225 		hpriv->target_pwr = NULL;
226 	}
227 
228 	for (i = 0; i < AHCI_MAX_CLKS; i++) {
229 		/*
230 		 * For now we must use clk_get(dev, NULL) for the first clock,
231 		 * because some platforms (da850, spear13xx) are not yet
232 		 * converted to use devicetree for clocks.  For new platforms
233 		 * this is equivalent to of_clk_get(dev->of_node, 0).
234 		 */
235 		if (i == 0)
236 			clk = clk_get(dev, NULL);
237 		else
238 			clk = of_clk_get(dev->of_node, i);
239 
240 		if (IS_ERR(clk)) {
241 			rc = PTR_ERR(clk);
242 			if (rc == -EPROBE_DEFER)
243 				goto err_out;
244 			break;
245 		}
246 		hpriv->clks[i] = clk;
247 	}
248 
249 	hpriv->phy = devm_phy_get(dev, "sata-phy");
250 	if (IS_ERR(hpriv->phy)) {
251 		rc = PTR_ERR(hpriv->phy);
252 		switch (rc) {
253 		case -ENODEV:
254 		case -ENOSYS:
255 			/* continue normally */
256 			hpriv->phy = NULL;
257 			break;
258 
259 		case -EPROBE_DEFER:
260 			goto err_out;
261 
262 		default:
263 			dev_err(dev, "couldn't get sata-phy\n");
264 			goto err_out;
265 		}
266 	}
267 
268 	pm_runtime_enable(dev);
269 	pm_runtime_get_sync(dev);
270 	hpriv->got_runtime_pm = true;
271 
272 	devres_remove_group(dev, NULL);
273 	return hpriv;
274 
275 err_out:
276 	devres_release_group(dev, NULL);
277 	return ERR_PTR(rc);
278 }
279 EXPORT_SYMBOL_GPL(ahci_platform_get_resources);
280 
281 /**
282  * ahci_platform_init_host - Bring up an ahci-platform host
283  * @pdev: platform device pointer for the host
284  * @hpriv: ahci-host private data for the host
285  * @pi_template: template for the ata_port_info to use
286  * @host_flags: ahci host flags used in ahci_host_priv
287  * @force_port_map: param passed to ahci_save_initial_config
288  * @mask_port_map: param passed to ahci_save_initial_config
289  *
290  * This function does all the usual steps needed to bring up an
291  * ahci-platform host, note any necessary resources (ie clks, phy, etc.)
292  * must be initialized / enabled before calling this.
293  *
294  * RETURNS:
295  * 0 on success otherwise a negative error code
296  */
297 int ahci_platform_init_host(struct platform_device *pdev,
298 			    struct ahci_host_priv *hpriv,
299 			    const struct ata_port_info *pi_template,
300 			    unsigned long host_flags,
301 			    unsigned int force_port_map,
302 			    unsigned int mask_port_map)
303 {
304 	struct device *dev = &pdev->dev;
305 	struct ata_port_info pi = *pi_template;
306 	const struct ata_port_info *ppi[] = { &pi, NULL };
307 	struct ata_host *host;
308 	int i, irq, n_ports, rc;
309 
310 	irq = platform_get_irq(pdev, 0);
311 	if (irq <= 0) {
312 		dev_err(dev, "no irq\n");
313 		return -EINVAL;
314 	}
315 
316 	/* prepare host */
317 	pi.private_data = (void *)host_flags;
318 	hpriv->flags |= host_flags;
319 
320 	ahci_save_initial_config(dev, hpriv, force_port_map, mask_port_map);
321 
322 	if (hpriv->cap & HOST_CAP_NCQ)
323 		pi.flags |= ATA_FLAG_NCQ;
324 
325 	if (hpriv->cap & HOST_CAP_PMP)
326 		pi.flags |= ATA_FLAG_PMP;
327 
328 	ahci_set_em_messages(hpriv, &pi);
329 
330 	/* CAP.NP sometimes indicate the index of the last enabled
331 	 * port, at other times, that of the last possible port, so
332 	 * determining the maximum port number requires looking at
333 	 * both CAP.NP and port_map.
334 	 */
335 	n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
336 
337 	host = ata_host_alloc_pinfo(dev, ppi, n_ports);
338 	if (!host)
339 		return -ENOMEM;
340 
341 	host->private_data = hpriv;
342 
343 	if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
344 		host->flags |= ATA_HOST_PARALLEL_SCAN;
345 	else
346 		dev_info(dev, "SSS flag set, parallel bus scan disabled\n");
347 
348 	if (pi.flags & ATA_FLAG_EM)
349 		ahci_reset_em(host);
350 
351 	for (i = 0; i < host->n_ports; i++) {
352 		struct ata_port *ap = host->ports[i];
353 
354 		ata_port_desc(ap, "mmio %pR",
355 			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
356 		ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
357 
358 		/* set enclosure management message type */
359 		if (ap->flags & ATA_FLAG_EM)
360 			ap->em_message_type = hpriv->em_msg_type;
361 
362 		/* disabled/not-implemented port */
363 		if (!(hpriv->port_map & (1 << i)))
364 			ap->ops = &ata_dummy_port_ops;
365 	}
366 
367 	rc = ahci_reset_controller(host);
368 	if (rc)
369 		return rc;
370 
371 	ahci_init_controller(host);
372 	ahci_print_info(host, "platform");
373 
374 	return ata_host_activate(host, irq, ahci_interrupt, IRQF_SHARED,
375 				 &ahci_platform_sht);
376 }
377 EXPORT_SYMBOL_GPL(ahci_platform_init_host);
378 
379 static void ahci_host_stop(struct ata_host *host)
380 {
381 	struct device *dev = host->dev;
382 	struct ahci_platform_data *pdata = dev_get_platdata(dev);
383 	struct ahci_host_priv *hpriv = host->private_data;
384 
385 	if (pdata && pdata->exit)
386 		pdata->exit(dev);
387 
388 	ahci_platform_disable_resources(hpriv);
389 }
390 
391 #ifdef CONFIG_PM_SLEEP
392 /**
393  * ahci_platform_suspend_host - Suspend an ahci-platform host
394  * @dev: device pointer for the host
395  *
396  * This function does all the usual steps needed to suspend an
397  * ahci-platform host, note any necessary resources (ie clks, phy, etc.)
398  * must be disabled after calling this.
399  *
400  * RETURNS:
401  * 0 on success otherwise a negative error code
402  */
403 int ahci_platform_suspend_host(struct device *dev)
404 {
405 	struct ata_host *host = dev_get_drvdata(dev);
406 	struct ahci_host_priv *hpriv = host->private_data;
407 	void __iomem *mmio = hpriv->mmio;
408 	u32 ctl;
409 
410 	if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
411 		dev_err(dev, "firmware update required for suspend/resume\n");
412 		return -EIO;
413 	}
414 
415 	/*
416 	 * AHCI spec rev1.1 section 8.3.3:
417 	 * Software must disable interrupts prior to requesting a
418 	 * transition of the HBA to D3 state.
419 	 */
420 	ctl = readl(mmio + HOST_CTL);
421 	ctl &= ~HOST_IRQ_EN;
422 	writel(ctl, mmio + HOST_CTL);
423 	readl(mmio + HOST_CTL); /* flush */
424 
425 	return ata_host_suspend(host, PMSG_SUSPEND);
426 }
427 EXPORT_SYMBOL_GPL(ahci_platform_suspend_host);
428 
429 /**
430  * ahci_platform_resume_host - Resume an ahci-platform host
431  * @dev: device pointer for the host
432  *
433  * This function does all the usual steps needed to resume an ahci-platform
434  * host, note any necessary resources (ie clks, phy, etc.)  must be
435  * initialized / enabled before calling this.
436  *
437  * RETURNS:
438  * 0 on success otherwise a negative error code
439  */
440 int ahci_platform_resume_host(struct device *dev)
441 {
442 	struct ata_host *host = dev_get_drvdata(dev);
443 	int rc;
444 
445 	if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
446 		rc = ahci_reset_controller(host);
447 		if (rc)
448 			return rc;
449 
450 		ahci_init_controller(host);
451 	}
452 
453 	ata_host_resume(host);
454 
455 	return 0;
456 }
457 EXPORT_SYMBOL_GPL(ahci_platform_resume_host);
458 
459 /**
460  * ahci_platform_suspend - Suspend an ahci-platform device
461  * @dev: the platform device to suspend
462  *
463  * This function suspends the host associated with the device, followed by
464  * disabling all the resources of the device.
465  *
466  * RETURNS:
467  * 0 on success otherwise a negative error code
468  */
469 int ahci_platform_suspend(struct device *dev)
470 {
471 	struct ahci_platform_data *pdata = dev_get_platdata(dev);
472 	struct ata_host *host = dev_get_drvdata(dev);
473 	struct ahci_host_priv *hpriv = host->private_data;
474 	int rc;
475 
476 	rc = ahci_platform_suspend_host(dev);
477 	if (rc)
478 		return rc;
479 
480 	if (pdata && pdata->suspend) {
481 		rc = pdata->suspend(dev);
482 		if (rc)
483 			goto resume_host;
484 	}
485 
486 	ahci_platform_disable_resources(hpriv);
487 
488 	return 0;
489 
490 resume_host:
491 	ahci_platform_resume_host(dev);
492 	return rc;
493 }
494 EXPORT_SYMBOL_GPL(ahci_platform_suspend);
495 
496 /**
497  * ahci_platform_resume - Resume an ahci-platform device
498  * @dev: the platform device to resume
499  *
500  * This function enables all the resources of the device followed by
501  * resuming the host associated with the device.
502  *
503  * RETURNS:
504  * 0 on success otherwise a negative error code
505  */
506 int ahci_platform_resume(struct device *dev)
507 {
508 	struct ahci_platform_data *pdata = dev_get_platdata(dev);
509 	struct ata_host *host = dev_get_drvdata(dev);
510 	struct ahci_host_priv *hpriv = host->private_data;
511 	int rc;
512 
513 	rc = ahci_platform_enable_resources(hpriv);
514 	if (rc)
515 		return rc;
516 
517 	if (pdata && pdata->resume) {
518 		rc = pdata->resume(dev);
519 		if (rc)
520 			goto disable_resources;
521 	}
522 
523 	rc = ahci_platform_resume_host(dev);
524 	if (rc)
525 		goto disable_resources;
526 
527 	/* We resumed so update PM runtime state */
528 	pm_runtime_disable(dev);
529 	pm_runtime_set_active(dev);
530 	pm_runtime_enable(dev);
531 
532 	return 0;
533 
534 disable_resources:
535 	ahci_platform_disable_resources(hpriv);
536 
537 	return rc;
538 }
539 EXPORT_SYMBOL_GPL(ahci_platform_resume);
540 #endif
541 
542 MODULE_DESCRIPTION("AHCI SATA platform library");
543 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
544 MODULE_LICENSE("GPL");
545