xref: /openbmc/linux/drivers/ata/libahci.c (revision 3821a065)
1 /*
2  *  libahci.c - Common AHCI SATA low-level routines
3  *
4  *  Maintained by:  Tejun Heo <tj@kernel.org>
5  *    		    Please ALWAYS copy linux-ide@vger.kernel.org
6  *		    on emails.
7  *
8  *  Copyright 2004-2005 Red Hat, Inc.
9  *
10  *
11  *  This program is free software; you can redistribute it and/or modify
12  *  it under the terms of the GNU General Public License as published by
13  *  the Free Software Foundation; either version 2, or (at your option)
14  *  any later version.
15  *
16  *  This program is distributed in the hope that it will be useful,
17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  *  GNU General Public License for more details.
20  *
21  *  You should have received a copy of the GNU General Public License
22  *  along with this program; see the file COPYING.  If not, write to
23  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
24  *
25  *
26  * libata documentation is available via 'make {ps|pdf}docs',
27  * as Documentation/DocBook/libata.*
28  *
29  * AHCI hardware documentation:
30  * http://www.intel.com/technology/serialata/pdf/rev1_0.pdf
31  * http://www.intel.com/technology/serialata/pdf/rev1_1.pdf
32  *
33  */
34 
35 #include <linux/kernel.h>
36 #include <linux/gfp.h>
37 #include <linux/module.h>
38 #include <linux/blkdev.h>
39 #include <linux/delay.h>
40 #include <linux/interrupt.h>
41 #include <linux/dma-mapping.h>
42 #include <linux/device.h>
43 #include <scsi/scsi_host.h>
44 #include <scsi/scsi_cmnd.h>
45 #include <linux/libata.h>
46 #include "ahci.h"
47 #include "libata.h"
48 
49 static int ahci_skip_host_reset;
50 int ahci_ignore_sss;
51 EXPORT_SYMBOL_GPL(ahci_ignore_sss);
52 
53 module_param_named(skip_host_reset, ahci_skip_host_reset, int, 0444);
54 MODULE_PARM_DESC(skip_host_reset, "skip global host reset (0=don't skip, 1=skip)");
55 
56 module_param_named(ignore_sss, ahci_ignore_sss, int, 0444);
57 MODULE_PARM_DESC(ignore_sss, "Ignore staggered spinup flag (0=don't ignore, 1=ignore)");
58 
59 static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
60 			unsigned hints);
61 static ssize_t ahci_led_show(struct ata_port *ap, char *buf);
62 static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
63 			      size_t size);
64 static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
65 					ssize_t size);
66 
67 
68 
69 static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val);
70 static int ahci_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val);
71 static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc);
72 static int ahci_port_start(struct ata_port *ap);
73 static void ahci_port_stop(struct ata_port *ap);
74 static void ahci_qc_prep(struct ata_queued_cmd *qc);
75 static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc);
76 static void ahci_freeze(struct ata_port *ap);
77 static void ahci_thaw(struct ata_port *ap);
78 static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep);
79 static void ahci_enable_fbs(struct ata_port *ap);
80 static void ahci_disable_fbs(struct ata_port *ap);
81 static void ahci_pmp_attach(struct ata_port *ap);
82 static void ahci_pmp_detach(struct ata_port *ap);
83 static int ahci_softreset(struct ata_link *link, unsigned int *class,
84 			  unsigned long deadline);
85 static int ahci_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
86 			  unsigned long deadline);
87 static int ahci_hardreset(struct ata_link *link, unsigned int *class,
88 			  unsigned long deadline);
89 static void ahci_postreset(struct ata_link *link, unsigned int *class);
90 static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
91 static void ahci_dev_config(struct ata_device *dev);
92 #ifdef CONFIG_PM
93 static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg);
94 #endif
95 static ssize_t ahci_activity_show(struct ata_device *dev, char *buf);
96 static ssize_t ahci_activity_store(struct ata_device *dev,
97 				   enum sw_activity val);
98 static void ahci_init_sw_activity(struct ata_link *link);
99 
100 static ssize_t ahci_show_host_caps(struct device *dev,
101 				   struct device_attribute *attr, char *buf);
102 static ssize_t ahci_show_host_cap2(struct device *dev,
103 				   struct device_attribute *attr, char *buf);
104 static ssize_t ahci_show_host_version(struct device *dev,
105 				      struct device_attribute *attr, char *buf);
106 static ssize_t ahci_show_port_cmd(struct device *dev,
107 				  struct device_attribute *attr, char *buf);
108 static ssize_t ahci_read_em_buffer(struct device *dev,
109 				   struct device_attribute *attr, char *buf);
110 static ssize_t ahci_store_em_buffer(struct device *dev,
111 				    struct device_attribute *attr,
112 				    const char *buf, size_t size);
113 static ssize_t ahci_show_em_supported(struct device *dev,
114 				      struct device_attribute *attr, char *buf);
115 
116 static DEVICE_ATTR(ahci_host_caps, S_IRUGO, ahci_show_host_caps, NULL);
117 static DEVICE_ATTR(ahci_host_cap2, S_IRUGO, ahci_show_host_cap2, NULL);
118 static DEVICE_ATTR(ahci_host_version, S_IRUGO, ahci_show_host_version, NULL);
119 static DEVICE_ATTR(ahci_port_cmd, S_IRUGO, ahci_show_port_cmd, NULL);
120 static DEVICE_ATTR(em_buffer, S_IWUSR | S_IRUGO,
121 		   ahci_read_em_buffer, ahci_store_em_buffer);
122 static DEVICE_ATTR(em_message_supported, S_IRUGO, ahci_show_em_supported, NULL);
123 
124 struct device_attribute *ahci_shost_attrs[] = {
125 	&dev_attr_link_power_management_policy,
126 	&dev_attr_em_message_type,
127 	&dev_attr_em_message,
128 	&dev_attr_ahci_host_caps,
129 	&dev_attr_ahci_host_cap2,
130 	&dev_attr_ahci_host_version,
131 	&dev_attr_ahci_port_cmd,
132 	&dev_attr_em_buffer,
133 	&dev_attr_em_message_supported,
134 	NULL
135 };
136 EXPORT_SYMBOL_GPL(ahci_shost_attrs);
137 
138 struct device_attribute *ahci_sdev_attrs[] = {
139 	&dev_attr_sw_activity,
140 	&dev_attr_unload_heads,
141 	NULL
142 };
143 EXPORT_SYMBOL_GPL(ahci_sdev_attrs);
144 
145 struct ata_port_operations ahci_ops = {
146 	.inherits		= &sata_pmp_port_ops,
147 
148 	.qc_defer		= ahci_pmp_qc_defer,
149 	.qc_prep		= ahci_qc_prep,
150 	.qc_issue		= ahci_qc_issue,
151 	.qc_fill_rtf		= ahci_qc_fill_rtf,
152 
153 	.freeze			= ahci_freeze,
154 	.thaw			= ahci_thaw,
155 	.softreset		= ahci_softreset,
156 	.hardreset		= ahci_hardreset,
157 	.postreset		= ahci_postreset,
158 	.pmp_softreset		= ahci_softreset,
159 	.error_handler		= ahci_error_handler,
160 	.post_internal_cmd	= ahci_post_internal_cmd,
161 	.dev_config		= ahci_dev_config,
162 
163 	.scr_read		= ahci_scr_read,
164 	.scr_write		= ahci_scr_write,
165 	.pmp_attach		= ahci_pmp_attach,
166 	.pmp_detach		= ahci_pmp_detach,
167 
168 	.set_lpm		= ahci_set_lpm,
169 	.em_show		= ahci_led_show,
170 	.em_store		= ahci_led_store,
171 	.sw_activity_show	= ahci_activity_show,
172 	.sw_activity_store	= ahci_activity_store,
173 	.transmit_led_message	= ahci_transmit_led_message,
174 #ifdef CONFIG_PM
175 	.port_suspend		= ahci_port_suspend,
176 	.port_resume		= ahci_port_resume,
177 #endif
178 	.port_start		= ahci_port_start,
179 	.port_stop		= ahci_port_stop,
180 };
181 EXPORT_SYMBOL_GPL(ahci_ops);
182 
183 struct ata_port_operations ahci_pmp_retry_srst_ops = {
184 	.inherits		= &ahci_ops,
185 	.softreset		= ahci_pmp_retry_softreset,
186 };
187 EXPORT_SYMBOL_GPL(ahci_pmp_retry_srst_ops);
188 
189 static bool ahci_em_messages __read_mostly = true;
190 EXPORT_SYMBOL_GPL(ahci_em_messages);
191 module_param(ahci_em_messages, bool, 0444);
192 /* add other LED protocol types when they become supported */
193 MODULE_PARM_DESC(ahci_em_messages,
194 	"AHCI Enclosure Management Message control (0 = off, 1 = on)");
195 
196 /* device sleep idle timeout in ms */
197 static int devslp_idle_timeout __read_mostly = 1000;
198 module_param(devslp_idle_timeout, int, 0644);
199 MODULE_PARM_DESC(devslp_idle_timeout, "device sleep idle timeout");
200 
201 static void ahci_enable_ahci(void __iomem *mmio)
202 {
203 	int i;
204 	u32 tmp;
205 
206 	/* turn on AHCI_EN */
207 	tmp = readl(mmio + HOST_CTL);
208 	if (tmp & HOST_AHCI_EN)
209 		return;
210 
211 	/* Some controllers need AHCI_EN to be written multiple times.
212 	 * Try a few times before giving up.
213 	 */
214 	for (i = 0; i < 5; i++) {
215 		tmp |= HOST_AHCI_EN;
216 		writel(tmp, mmio + HOST_CTL);
217 		tmp = readl(mmio + HOST_CTL);	/* flush && sanity check */
218 		if (tmp & HOST_AHCI_EN)
219 			return;
220 		msleep(10);
221 	}
222 
223 	WARN_ON(1);
224 }
225 
226 static ssize_t ahci_show_host_caps(struct device *dev,
227 				   struct device_attribute *attr, char *buf)
228 {
229 	struct Scsi_Host *shost = class_to_shost(dev);
230 	struct ata_port *ap = ata_shost_to_port(shost);
231 	struct ahci_host_priv *hpriv = ap->host->private_data;
232 
233 	return sprintf(buf, "%x\n", hpriv->cap);
234 }
235 
236 static ssize_t ahci_show_host_cap2(struct device *dev,
237 				   struct device_attribute *attr, char *buf)
238 {
239 	struct Scsi_Host *shost = class_to_shost(dev);
240 	struct ata_port *ap = ata_shost_to_port(shost);
241 	struct ahci_host_priv *hpriv = ap->host->private_data;
242 
243 	return sprintf(buf, "%x\n", hpriv->cap2);
244 }
245 
246 static ssize_t ahci_show_host_version(struct device *dev,
247 				   struct device_attribute *attr, char *buf)
248 {
249 	struct Scsi_Host *shost = class_to_shost(dev);
250 	struct ata_port *ap = ata_shost_to_port(shost);
251 	struct ahci_host_priv *hpriv = ap->host->private_data;
252 	void __iomem *mmio = hpriv->mmio;
253 
254 	return sprintf(buf, "%x\n", readl(mmio + HOST_VERSION));
255 }
256 
257 static ssize_t ahci_show_port_cmd(struct device *dev,
258 				  struct device_attribute *attr, char *buf)
259 {
260 	struct Scsi_Host *shost = class_to_shost(dev);
261 	struct ata_port *ap = ata_shost_to_port(shost);
262 	void __iomem *port_mmio = ahci_port_base(ap);
263 
264 	return sprintf(buf, "%x\n", readl(port_mmio + PORT_CMD));
265 }
266 
267 static ssize_t ahci_read_em_buffer(struct device *dev,
268 				   struct device_attribute *attr, char *buf)
269 {
270 	struct Scsi_Host *shost = class_to_shost(dev);
271 	struct ata_port *ap = ata_shost_to_port(shost);
272 	struct ahci_host_priv *hpriv = ap->host->private_data;
273 	void __iomem *mmio = hpriv->mmio;
274 	void __iomem *em_mmio = mmio + hpriv->em_loc;
275 	u32 em_ctl, msg;
276 	unsigned long flags;
277 	size_t count;
278 	int i;
279 
280 	spin_lock_irqsave(ap->lock, flags);
281 
282 	em_ctl = readl(mmio + HOST_EM_CTL);
283 	if (!(ap->flags & ATA_FLAG_EM) || em_ctl & EM_CTL_XMT ||
284 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO)) {
285 		spin_unlock_irqrestore(ap->lock, flags);
286 		return -EINVAL;
287 	}
288 
289 	if (!(em_ctl & EM_CTL_MR)) {
290 		spin_unlock_irqrestore(ap->lock, flags);
291 		return -EAGAIN;
292 	}
293 
294 	if (!(em_ctl & EM_CTL_SMB))
295 		em_mmio += hpriv->em_buf_sz;
296 
297 	count = hpriv->em_buf_sz;
298 
299 	/* the count should not be larger than PAGE_SIZE */
300 	if (count > PAGE_SIZE) {
301 		if (printk_ratelimit())
302 			ata_port_warn(ap,
303 				      "EM read buffer size too large: "
304 				      "buffer size %u, page size %lu\n",
305 				      hpriv->em_buf_sz, PAGE_SIZE);
306 		count = PAGE_SIZE;
307 	}
308 
309 	for (i = 0; i < count; i += 4) {
310 		msg = readl(em_mmio + i);
311 		buf[i] = msg & 0xff;
312 		buf[i + 1] = (msg >> 8) & 0xff;
313 		buf[i + 2] = (msg >> 16) & 0xff;
314 		buf[i + 3] = (msg >> 24) & 0xff;
315 	}
316 
317 	spin_unlock_irqrestore(ap->lock, flags);
318 
319 	return i;
320 }
321 
322 static ssize_t ahci_store_em_buffer(struct device *dev,
323 				    struct device_attribute *attr,
324 				    const char *buf, size_t size)
325 {
326 	struct Scsi_Host *shost = class_to_shost(dev);
327 	struct ata_port *ap = ata_shost_to_port(shost);
328 	struct ahci_host_priv *hpriv = ap->host->private_data;
329 	void __iomem *mmio = hpriv->mmio;
330 	void __iomem *em_mmio = mmio + hpriv->em_loc;
331 	const unsigned char *msg_buf = buf;
332 	u32 em_ctl, msg;
333 	unsigned long flags;
334 	int i;
335 
336 	/* check size validity */
337 	if (!(ap->flags & ATA_FLAG_EM) ||
338 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO) ||
339 	    size % 4 || size > hpriv->em_buf_sz)
340 		return -EINVAL;
341 
342 	spin_lock_irqsave(ap->lock, flags);
343 
344 	em_ctl = readl(mmio + HOST_EM_CTL);
345 	if (em_ctl & EM_CTL_TM) {
346 		spin_unlock_irqrestore(ap->lock, flags);
347 		return -EBUSY;
348 	}
349 
350 	for (i = 0; i < size; i += 4) {
351 		msg = msg_buf[i] | msg_buf[i + 1] << 8 |
352 		      msg_buf[i + 2] << 16 | msg_buf[i + 3] << 24;
353 		writel(msg, em_mmio + i);
354 	}
355 
356 	writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
357 
358 	spin_unlock_irqrestore(ap->lock, flags);
359 
360 	return size;
361 }
362 
363 static ssize_t ahci_show_em_supported(struct device *dev,
364 				      struct device_attribute *attr, char *buf)
365 {
366 	struct Scsi_Host *shost = class_to_shost(dev);
367 	struct ata_port *ap = ata_shost_to_port(shost);
368 	struct ahci_host_priv *hpriv = ap->host->private_data;
369 	void __iomem *mmio = hpriv->mmio;
370 	u32 em_ctl;
371 
372 	em_ctl = readl(mmio + HOST_EM_CTL);
373 
374 	return sprintf(buf, "%s%s%s%s\n",
375 		       em_ctl & EM_CTL_LED ? "led " : "",
376 		       em_ctl & EM_CTL_SAFTE ? "saf-te " : "",
377 		       em_ctl & EM_CTL_SES ? "ses-2 " : "",
378 		       em_ctl & EM_CTL_SGPIO ? "sgpio " : "");
379 }
380 
381 /**
382  *	ahci_save_initial_config - Save and fixup initial config values
383  *	@dev: target AHCI device
384  *	@hpriv: host private area to store config values
385  *
386  *	Some registers containing configuration info might be setup by
387  *	BIOS and might be cleared on reset.  This function saves the
388  *	initial values of those registers into @hpriv such that they
389  *	can be restored after controller reset.
390  *
391  *	If inconsistent, config values are fixed up by this function.
392  *
393  *	If it is not set already this function sets hpriv->start_engine to
394  *	ahci_start_engine.
395  *
396  *	LOCKING:
397  *	None.
398  */
399 void ahci_save_initial_config(struct device *dev, struct ahci_host_priv *hpriv)
400 {
401 	void __iomem *mmio = hpriv->mmio;
402 	u32 cap, cap2, vers, port_map;
403 	int i;
404 
405 	/* make sure AHCI mode is enabled before accessing CAP */
406 	ahci_enable_ahci(mmio);
407 
408 	/* Values prefixed with saved_ are written back to host after
409 	 * reset.  Values without are used for driver operation.
410 	 */
411 	hpriv->saved_cap = cap = readl(mmio + HOST_CAP);
412 	hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL);
413 
414 	/* CAP2 register is only defined for AHCI 1.2 and later */
415 	vers = readl(mmio + HOST_VERSION);
416 	if ((vers >> 16) > 1 ||
417 	   ((vers >> 16) == 1 && (vers & 0xFFFF) >= 0x200))
418 		hpriv->saved_cap2 = cap2 = readl(mmio + HOST_CAP2);
419 	else
420 		hpriv->saved_cap2 = cap2 = 0;
421 
422 	/* some chips have errata preventing 64bit use */
423 	if ((cap & HOST_CAP_64) && (hpriv->flags & AHCI_HFLAG_32BIT_ONLY)) {
424 		dev_info(dev, "controller can't do 64bit DMA, forcing 32bit\n");
425 		cap &= ~HOST_CAP_64;
426 	}
427 
428 	if ((cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_NO_NCQ)) {
429 		dev_info(dev, "controller can't do NCQ, turning off CAP_NCQ\n");
430 		cap &= ~HOST_CAP_NCQ;
431 	}
432 
433 	if (!(cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_YES_NCQ)) {
434 		dev_info(dev, "controller can do NCQ, turning on CAP_NCQ\n");
435 		cap |= HOST_CAP_NCQ;
436 	}
437 
438 	if ((cap & HOST_CAP_PMP) && (hpriv->flags & AHCI_HFLAG_NO_PMP)) {
439 		dev_info(dev, "controller can't do PMP, turning off CAP_PMP\n");
440 		cap &= ~HOST_CAP_PMP;
441 	}
442 
443 	if ((cap & HOST_CAP_SNTF) && (hpriv->flags & AHCI_HFLAG_NO_SNTF)) {
444 		dev_info(dev,
445 			 "controller can't do SNTF, turning off CAP_SNTF\n");
446 		cap &= ~HOST_CAP_SNTF;
447 	}
448 
449 	if ((cap2 & HOST_CAP2_SDS) && (hpriv->flags & AHCI_HFLAG_NO_DEVSLP)) {
450 		dev_info(dev,
451 			 "controller can't do DEVSLP, turning off\n");
452 		cap2 &= ~HOST_CAP2_SDS;
453 		cap2 &= ~HOST_CAP2_SADM;
454 	}
455 
456 	if (!(cap & HOST_CAP_FBS) && (hpriv->flags & AHCI_HFLAG_YES_FBS)) {
457 		dev_info(dev, "controller can do FBS, turning on CAP_FBS\n");
458 		cap |= HOST_CAP_FBS;
459 	}
460 
461 	if ((cap & HOST_CAP_FBS) && (hpriv->flags & AHCI_HFLAG_NO_FBS)) {
462 		dev_info(dev, "controller can't do FBS, turning off CAP_FBS\n");
463 		cap &= ~HOST_CAP_FBS;
464 	}
465 
466 	if (hpriv->force_port_map && port_map != hpriv->force_port_map) {
467 		dev_info(dev, "forcing port_map 0x%x -> 0x%x\n",
468 			 port_map, hpriv->force_port_map);
469 		port_map = hpriv->force_port_map;
470 	}
471 
472 	if (hpriv->mask_port_map) {
473 		dev_warn(dev, "masking port_map 0x%x -> 0x%x\n",
474 			port_map,
475 			port_map & hpriv->mask_port_map);
476 		port_map &= hpriv->mask_port_map;
477 	}
478 
479 	/* cross check port_map and cap.n_ports */
480 	if (port_map) {
481 		int map_ports = 0;
482 
483 		for (i = 0; i < AHCI_MAX_PORTS; i++)
484 			if (port_map & (1 << i))
485 				map_ports++;
486 
487 		/* If PI has more ports than n_ports, whine, clear
488 		 * port_map and let it be generated from n_ports.
489 		 */
490 		if (map_ports > ahci_nr_ports(cap)) {
491 			dev_warn(dev,
492 				 "implemented port map (0x%x) contains more ports than nr_ports (%u), using nr_ports\n",
493 				 port_map, ahci_nr_ports(cap));
494 			port_map = 0;
495 		}
496 	}
497 
498 	/* fabricate port_map from cap.nr_ports */
499 	if (!port_map) {
500 		port_map = (1 << ahci_nr_ports(cap)) - 1;
501 		dev_warn(dev, "forcing PORTS_IMPL to 0x%x\n", port_map);
502 
503 		/* write the fixed up value to the PI register */
504 		hpriv->saved_port_map = port_map;
505 	}
506 
507 	/* record values to use during operation */
508 	hpriv->cap = cap;
509 	hpriv->cap2 = cap2;
510 	hpriv->port_map = port_map;
511 
512 	if (!hpriv->start_engine)
513 		hpriv->start_engine = ahci_start_engine;
514 }
515 EXPORT_SYMBOL_GPL(ahci_save_initial_config);
516 
517 /**
518  *	ahci_restore_initial_config - Restore initial config
519  *	@host: target ATA host
520  *
521  *	Restore initial config stored by ahci_save_initial_config().
522  *
523  *	LOCKING:
524  *	None.
525  */
526 static void ahci_restore_initial_config(struct ata_host *host)
527 {
528 	struct ahci_host_priv *hpriv = host->private_data;
529 	void __iomem *mmio = hpriv->mmio;
530 
531 	writel(hpriv->saved_cap, mmio + HOST_CAP);
532 	if (hpriv->saved_cap2)
533 		writel(hpriv->saved_cap2, mmio + HOST_CAP2);
534 	writel(hpriv->saved_port_map, mmio + HOST_PORTS_IMPL);
535 	(void) readl(mmio + HOST_PORTS_IMPL);	/* flush */
536 }
537 
538 static unsigned ahci_scr_offset(struct ata_port *ap, unsigned int sc_reg)
539 {
540 	static const int offset[] = {
541 		[SCR_STATUS]		= PORT_SCR_STAT,
542 		[SCR_CONTROL]		= PORT_SCR_CTL,
543 		[SCR_ERROR]		= PORT_SCR_ERR,
544 		[SCR_ACTIVE]		= PORT_SCR_ACT,
545 		[SCR_NOTIFICATION]	= PORT_SCR_NTF,
546 	};
547 	struct ahci_host_priv *hpriv = ap->host->private_data;
548 
549 	if (sc_reg < ARRAY_SIZE(offset) &&
550 	    (sc_reg != SCR_NOTIFICATION || (hpriv->cap & HOST_CAP_SNTF)))
551 		return offset[sc_reg];
552 	return 0;
553 }
554 
555 static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val)
556 {
557 	void __iomem *port_mmio = ahci_port_base(link->ap);
558 	int offset = ahci_scr_offset(link->ap, sc_reg);
559 
560 	if (offset) {
561 		*val = readl(port_mmio + offset);
562 		return 0;
563 	}
564 	return -EINVAL;
565 }
566 
567 static int ahci_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val)
568 {
569 	void __iomem *port_mmio = ahci_port_base(link->ap);
570 	int offset = ahci_scr_offset(link->ap, sc_reg);
571 
572 	if (offset) {
573 		writel(val, port_mmio + offset);
574 		return 0;
575 	}
576 	return -EINVAL;
577 }
578 
579 void ahci_start_engine(struct ata_port *ap)
580 {
581 	void __iomem *port_mmio = ahci_port_base(ap);
582 	u32 tmp;
583 
584 	/* start DMA */
585 	tmp = readl(port_mmio + PORT_CMD);
586 	tmp |= PORT_CMD_START;
587 	writel(tmp, port_mmio + PORT_CMD);
588 	readl(port_mmio + PORT_CMD); /* flush */
589 }
590 EXPORT_SYMBOL_GPL(ahci_start_engine);
591 
592 int ahci_stop_engine(struct ata_port *ap)
593 {
594 	void __iomem *port_mmio = ahci_port_base(ap);
595 	u32 tmp;
596 
597 	tmp = readl(port_mmio + PORT_CMD);
598 
599 	/* check if the HBA is idle */
600 	if ((tmp & (PORT_CMD_START | PORT_CMD_LIST_ON)) == 0)
601 		return 0;
602 
603 	/* setting HBA to idle */
604 	tmp &= ~PORT_CMD_START;
605 	writel(tmp, port_mmio + PORT_CMD);
606 
607 	/* wait for engine to stop. This could be as long as 500 msec */
608 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
609 				PORT_CMD_LIST_ON, PORT_CMD_LIST_ON, 1, 500);
610 	if (tmp & PORT_CMD_LIST_ON)
611 		return -EIO;
612 
613 	return 0;
614 }
615 EXPORT_SYMBOL_GPL(ahci_stop_engine);
616 
617 void ahci_start_fis_rx(struct ata_port *ap)
618 {
619 	void __iomem *port_mmio = ahci_port_base(ap);
620 	struct ahci_host_priv *hpriv = ap->host->private_data;
621 	struct ahci_port_priv *pp = ap->private_data;
622 	u32 tmp;
623 
624 	/* set FIS registers */
625 	if (hpriv->cap & HOST_CAP_64)
626 		writel((pp->cmd_slot_dma >> 16) >> 16,
627 		       port_mmio + PORT_LST_ADDR_HI);
628 	writel(pp->cmd_slot_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);
629 
630 	if (hpriv->cap & HOST_CAP_64)
631 		writel((pp->rx_fis_dma >> 16) >> 16,
632 		       port_mmio + PORT_FIS_ADDR_HI);
633 	writel(pp->rx_fis_dma & 0xffffffff, port_mmio + PORT_FIS_ADDR);
634 
635 	/* enable FIS reception */
636 	tmp = readl(port_mmio + PORT_CMD);
637 	tmp |= PORT_CMD_FIS_RX;
638 	writel(tmp, port_mmio + PORT_CMD);
639 
640 	/* flush */
641 	readl(port_mmio + PORT_CMD);
642 }
643 EXPORT_SYMBOL_GPL(ahci_start_fis_rx);
644 
645 static int ahci_stop_fis_rx(struct ata_port *ap)
646 {
647 	void __iomem *port_mmio = ahci_port_base(ap);
648 	u32 tmp;
649 
650 	/* disable FIS reception */
651 	tmp = readl(port_mmio + PORT_CMD);
652 	tmp &= ~PORT_CMD_FIS_RX;
653 	writel(tmp, port_mmio + PORT_CMD);
654 
655 	/* wait for completion, spec says 500ms, give it 1000 */
656 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD, PORT_CMD_FIS_ON,
657 				PORT_CMD_FIS_ON, 10, 1000);
658 	if (tmp & PORT_CMD_FIS_ON)
659 		return -EBUSY;
660 
661 	return 0;
662 }
663 
664 static void ahci_power_up(struct ata_port *ap)
665 {
666 	struct ahci_host_priv *hpriv = ap->host->private_data;
667 	void __iomem *port_mmio = ahci_port_base(ap);
668 	u32 cmd;
669 
670 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
671 
672 	/* spin up device */
673 	if (hpriv->cap & HOST_CAP_SSS) {
674 		cmd |= PORT_CMD_SPIN_UP;
675 		writel(cmd, port_mmio + PORT_CMD);
676 	}
677 
678 	/* wake up link */
679 	writel(cmd | PORT_CMD_ICC_ACTIVE, port_mmio + PORT_CMD);
680 }
681 
682 static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
683 			unsigned int hints)
684 {
685 	struct ata_port *ap = link->ap;
686 	struct ahci_host_priv *hpriv = ap->host->private_data;
687 	struct ahci_port_priv *pp = ap->private_data;
688 	void __iomem *port_mmio = ahci_port_base(ap);
689 
690 	if (policy != ATA_LPM_MAX_POWER) {
691 		/*
692 		 * Disable interrupts on Phy Ready. This keeps us from
693 		 * getting woken up due to spurious phy ready
694 		 * interrupts.
695 		 */
696 		pp->intr_mask &= ~PORT_IRQ_PHYRDY;
697 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
698 
699 		sata_link_scr_lpm(link, policy, false);
700 	}
701 
702 	if (hpriv->cap & HOST_CAP_ALPM) {
703 		u32 cmd = readl(port_mmio + PORT_CMD);
704 
705 		if (policy == ATA_LPM_MAX_POWER || !(hints & ATA_LPM_HIPM)) {
706 			cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE);
707 			cmd |= PORT_CMD_ICC_ACTIVE;
708 
709 			writel(cmd, port_mmio + PORT_CMD);
710 			readl(port_mmio + PORT_CMD);
711 
712 			/* wait 10ms to be sure we've come out of LPM state */
713 			ata_msleep(ap, 10);
714 		} else {
715 			cmd |= PORT_CMD_ALPE;
716 			if (policy == ATA_LPM_MIN_POWER)
717 				cmd |= PORT_CMD_ASP;
718 
719 			/* write out new cmd value */
720 			writel(cmd, port_mmio + PORT_CMD);
721 		}
722 	}
723 
724 	/* set aggressive device sleep */
725 	if ((hpriv->cap2 & HOST_CAP2_SDS) &&
726 	    (hpriv->cap2 & HOST_CAP2_SADM) &&
727 	    (link->device->flags & ATA_DFLAG_DEVSLP)) {
728 		if (policy == ATA_LPM_MIN_POWER)
729 			ahci_set_aggressive_devslp(ap, true);
730 		else
731 			ahci_set_aggressive_devslp(ap, false);
732 	}
733 
734 	if (policy == ATA_LPM_MAX_POWER) {
735 		sata_link_scr_lpm(link, policy, false);
736 
737 		/* turn PHYRDY IRQ back on */
738 		pp->intr_mask |= PORT_IRQ_PHYRDY;
739 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
740 	}
741 
742 	return 0;
743 }
744 
745 #ifdef CONFIG_PM
746 static void ahci_power_down(struct ata_port *ap)
747 {
748 	struct ahci_host_priv *hpriv = ap->host->private_data;
749 	void __iomem *port_mmio = ahci_port_base(ap);
750 	u32 cmd, scontrol;
751 
752 	if (!(hpriv->cap & HOST_CAP_SSS))
753 		return;
754 
755 	/* put device into listen mode, first set PxSCTL.DET to 0 */
756 	scontrol = readl(port_mmio + PORT_SCR_CTL);
757 	scontrol &= ~0xf;
758 	writel(scontrol, port_mmio + PORT_SCR_CTL);
759 
760 	/* then set PxCMD.SUD to 0 */
761 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
762 	cmd &= ~PORT_CMD_SPIN_UP;
763 	writel(cmd, port_mmio + PORT_CMD);
764 }
765 #endif
766 
767 static void ahci_start_port(struct ata_port *ap)
768 {
769 	struct ahci_host_priv *hpriv = ap->host->private_data;
770 	struct ahci_port_priv *pp = ap->private_data;
771 	struct ata_link *link;
772 	struct ahci_em_priv *emp;
773 	ssize_t rc;
774 	int i;
775 
776 	/* enable FIS reception */
777 	ahci_start_fis_rx(ap);
778 
779 	/* enable DMA */
780 	if (!(hpriv->flags & AHCI_HFLAG_DELAY_ENGINE))
781 		hpriv->start_engine(ap);
782 
783 	/* turn on LEDs */
784 	if (ap->flags & ATA_FLAG_EM) {
785 		ata_for_each_link(link, ap, EDGE) {
786 			emp = &pp->em_priv[link->pmp];
787 
788 			/* EM Transmit bit maybe busy during init */
789 			for (i = 0; i < EM_MAX_RETRY; i++) {
790 				rc = ap->ops->transmit_led_message(ap,
791 							       emp->led_state,
792 							       4);
793 				/*
794 				 * If busy, give a breather but do not
795 				 * release EH ownership by using msleep()
796 				 * instead of ata_msleep().  EM Transmit
797 				 * bit is busy for the whole host and
798 				 * releasing ownership will cause other
799 				 * ports to fail the same way.
800 				 */
801 				if (rc == -EBUSY)
802 					msleep(1);
803 				else
804 					break;
805 			}
806 		}
807 	}
808 
809 	if (ap->flags & ATA_FLAG_SW_ACTIVITY)
810 		ata_for_each_link(link, ap, EDGE)
811 			ahci_init_sw_activity(link);
812 
813 }
814 
815 static int ahci_deinit_port(struct ata_port *ap, const char **emsg)
816 {
817 	int rc;
818 
819 	/* disable DMA */
820 	rc = ahci_stop_engine(ap);
821 	if (rc) {
822 		*emsg = "failed to stop engine";
823 		return rc;
824 	}
825 
826 	/* disable FIS reception */
827 	rc = ahci_stop_fis_rx(ap);
828 	if (rc) {
829 		*emsg = "failed stop FIS RX";
830 		return rc;
831 	}
832 
833 	return 0;
834 }
835 
836 int ahci_reset_controller(struct ata_host *host)
837 {
838 	struct ahci_host_priv *hpriv = host->private_data;
839 	void __iomem *mmio = hpriv->mmio;
840 	u32 tmp;
841 
842 	/* we must be in AHCI mode, before using anything
843 	 * AHCI-specific, such as HOST_RESET.
844 	 */
845 	ahci_enable_ahci(mmio);
846 
847 	/* global controller reset */
848 	if (!ahci_skip_host_reset) {
849 		tmp = readl(mmio + HOST_CTL);
850 		if ((tmp & HOST_RESET) == 0) {
851 			writel(tmp | HOST_RESET, mmio + HOST_CTL);
852 			readl(mmio + HOST_CTL); /* flush */
853 		}
854 
855 		/*
856 		 * to perform host reset, OS should set HOST_RESET
857 		 * and poll until this bit is read to be "0".
858 		 * reset must complete within 1 second, or
859 		 * the hardware should be considered fried.
860 		 */
861 		tmp = ata_wait_register(NULL, mmio + HOST_CTL, HOST_RESET,
862 					HOST_RESET, 10, 1000);
863 
864 		if (tmp & HOST_RESET) {
865 			dev_err(host->dev, "controller reset failed (0x%x)\n",
866 				tmp);
867 			return -EIO;
868 		}
869 
870 		/* turn on AHCI mode */
871 		ahci_enable_ahci(mmio);
872 
873 		/* Some registers might be cleared on reset.  Restore
874 		 * initial values.
875 		 */
876 		ahci_restore_initial_config(host);
877 	} else
878 		dev_info(host->dev, "skipping global host reset\n");
879 
880 	return 0;
881 }
882 EXPORT_SYMBOL_GPL(ahci_reset_controller);
883 
884 static void ahci_sw_activity(struct ata_link *link)
885 {
886 	struct ata_port *ap = link->ap;
887 	struct ahci_port_priv *pp = ap->private_data;
888 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
889 
890 	if (!(link->flags & ATA_LFLAG_SW_ACTIVITY))
891 		return;
892 
893 	emp->activity++;
894 	if (!timer_pending(&emp->timer))
895 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(10));
896 }
897 
898 static void ahci_sw_activity_blink(unsigned long arg)
899 {
900 	struct ata_link *link = (struct ata_link *)arg;
901 	struct ata_port *ap = link->ap;
902 	struct ahci_port_priv *pp = ap->private_data;
903 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
904 	unsigned long led_message = emp->led_state;
905 	u32 activity_led_state;
906 	unsigned long flags;
907 
908 	led_message &= EM_MSG_LED_VALUE;
909 	led_message |= ap->port_no | (link->pmp << 8);
910 
911 	/* check to see if we've had activity.  If so,
912 	 * toggle state of LED and reset timer.  If not,
913 	 * turn LED to desired idle state.
914 	 */
915 	spin_lock_irqsave(ap->lock, flags);
916 	if (emp->saved_activity != emp->activity) {
917 		emp->saved_activity = emp->activity;
918 		/* get the current LED state */
919 		activity_led_state = led_message & EM_MSG_LED_VALUE_ON;
920 
921 		if (activity_led_state)
922 			activity_led_state = 0;
923 		else
924 			activity_led_state = 1;
925 
926 		/* clear old state */
927 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
928 
929 		/* toggle state */
930 		led_message |= (activity_led_state << 16);
931 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(100));
932 	} else {
933 		/* switch to idle */
934 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
935 		if (emp->blink_policy == BLINK_OFF)
936 			led_message |= (1 << 16);
937 	}
938 	spin_unlock_irqrestore(ap->lock, flags);
939 	ap->ops->transmit_led_message(ap, led_message, 4);
940 }
941 
942 static void ahci_init_sw_activity(struct ata_link *link)
943 {
944 	struct ata_port *ap = link->ap;
945 	struct ahci_port_priv *pp = ap->private_data;
946 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
947 
948 	/* init activity stats, setup timer */
949 	emp->saved_activity = emp->activity = 0;
950 	setup_timer(&emp->timer, ahci_sw_activity_blink, (unsigned long)link);
951 
952 	/* check our blink policy and set flag for link if it's enabled */
953 	if (emp->blink_policy)
954 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
955 }
956 
957 int ahci_reset_em(struct ata_host *host)
958 {
959 	struct ahci_host_priv *hpriv = host->private_data;
960 	void __iomem *mmio = hpriv->mmio;
961 	u32 em_ctl;
962 
963 	em_ctl = readl(mmio + HOST_EM_CTL);
964 	if ((em_ctl & EM_CTL_TM) || (em_ctl & EM_CTL_RST))
965 		return -EINVAL;
966 
967 	writel(em_ctl | EM_CTL_RST, mmio + HOST_EM_CTL);
968 	return 0;
969 }
970 EXPORT_SYMBOL_GPL(ahci_reset_em);
971 
972 static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
973 					ssize_t size)
974 {
975 	struct ahci_host_priv *hpriv = ap->host->private_data;
976 	struct ahci_port_priv *pp = ap->private_data;
977 	void __iomem *mmio = hpriv->mmio;
978 	u32 em_ctl;
979 	u32 message[] = {0, 0};
980 	unsigned long flags;
981 	int pmp;
982 	struct ahci_em_priv *emp;
983 
984 	/* get the slot number from the message */
985 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
986 	if (pmp < EM_MAX_SLOTS)
987 		emp = &pp->em_priv[pmp];
988 	else
989 		return -EINVAL;
990 
991 	spin_lock_irqsave(ap->lock, flags);
992 
993 	/*
994 	 * if we are still busy transmitting a previous message,
995 	 * do not allow
996 	 */
997 	em_ctl = readl(mmio + HOST_EM_CTL);
998 	if (em_ctl & EM_CTL_TM) {
999 		spin_unlock_irqrestore(ap->lock, flags);
1000 		return -EBUSY;
1001 	}
1002 
1003 	if (hpriv->em_msg_type & EM_MSG_TYPE_LED) {
1004 		/*
1005 		 * create message header - this is all zero except for
1006 		 * the message size, which is 4 bytes.
1007 		 */
1008 		message[0] |= (4 << 8);
1009 
1010 		/* ignore 0:4 of byte zero, fill in port info yourself */
1011 		message[1] = ((state & ~EM_MSG_LED_HBA_PORT) | ap->port_no);
1012 
1013 		/* write message to EM_LOC */
1014 		writel(message[0], mmio + hpriv->em_loc);
1015 		writel(message[1], mmio + hpriv->em_loc+4);
1016 
1017 		/*
1018 		 * tell hardware to transmit the message
1019 		 */
1020 		writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
1021 	}
1022 
1023 	/* save off new led state for port/slot */
1024 	emp->led_state = state;
1025 
1026 	spin_unlock_irqrestore(ap->lock, flags);
1027 	return size;
1028 }
1029 
1030 static ssize_t ahci_led_show(struct ata_port *ap, char *buf)
1031 {
1032 	struct ahci_port_priv *pp = ap->private_data;
1033 	struct ata_link *link;
1034 	struct ahci_em_priv *emp;
1035 	int rc = 0;
1036 
1037 	ata_for_each_link(link, ap, EDGE) {
1038 		emp = &pp->em_priv[link->pmp];
1039 		rc += sprintf(buf, "%lx\n", emp->led_state);
1040 	}
1041 	return rc;
1042 }
1043 
1044 static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
1045 				size_t size)
1046 {
1047 	unsigned int state;
1048 	int pmp;
1049 	struct ahci_port_priv *pp = ap->private_data;
1050 	struct ahci_em_priv *emp;
1051 
1052 	if (kstrtouint(buf, 0, &state) < 0)
1053 		return -EINVAL;
1054 
1055 	/* get the slot number from the message */
1056 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
1057 	if (pmp < EM_MAX_SLOTS)
1058 		emp = &pp->em_priv[pmp];
1059 	else
1060 		return -EINVAL;
1061 
1062 	/* mask off the activity bits if we are in sw_activity
1063 	 * mode, user should turn off sw_activity before setting
1064 	 * activity led through em_message
1065 	 */
1066 	if (emp->blink_policy)
1067 		state &= ~EM_MSG_LED_VALUE_ACTIVITY;
1068 
1069 	return ap->ops->transmit_led_message(ap, state, size);
1070 }
1071 
1072 static ssize_t ahci_activity_store(struct ata_device *dev, enum sw_activity val)
1073 {
1074 	struct ata_link *link = dev->link;
1075 	struct ata_port *ap = link->ap;
1076 	struct ahci_port_priv *pp = ap->private_data;
1077 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1078 	u32 port_led_state = emp->led_state;
1079 
1080 	/* save the desired Activity LED behavior */
1081 	if (val == OFF) {
1082 		/* clear LFLAG */
1083 		link->flags &= ~(ATA_LFLAG_SW_ACTIVITY);
1084 
1085 		/* set the LED to OFF */
1086 		port_led_state &= EM_MSG_LED_VALUE_OFF;
1087 		port_led_state |= (ap->port_no | (link->pmp << 8));
1088 		ap->ops->transmit_led_message(ap, port_led_state, 4);
1089 	} else {
1090 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
1091 		if (val == BLINK_OFF) {
1092 			/* set LED to ON for idle */
1093 			port_led_state &= EM_MSG_LED_VALUE_OFF;
1094 			port_led_state |= (ap->port_no | (link->pmp << 8));
1095 			port_led_state |= EM_MSG_LED_VALUE_ON; /* check this */
1096 			ap->ops->transmit_led_message(ap, port_led_state, 4);
1097 		}
1098 	}
1099 	emp->blink_policy = val;
1100 	return 0;
1101 }
1102 
1103 static ssize_t ahci_activity_show(struct ata_device *dev, char *buf)
1104 {
1105 	struct ata_link *link = dev->link;
1106 	struct ata_port *ap = link->ap;
1107 	struct ahci_port_priv *pp = ap->private_data;
1108 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1109 
1110 	/* display the saved value of activity behavior for this
1111 	 * disk.
1112 	 */
1113 	return sprintf(buf, "%d\n", emp->blink_policy);
1114 }
1115 
1116 static void ahci_port_init(struct device *dev, struct ata_port *ap,
1117 			   int port_no, void __iomem *mmio,
1118 			   void __iomem *port_mmio)
1119 {
1120 	const char *emsg = NULL;
1121 	int rc;
1122 	u32 tmp;
1123 
1124 	/* make sure port is not active */
1125 	rc = ahci_deinit_port(ap, &emsg);
1126 	if (rc)
1127 		dev_warn(dev, "%s (%d)\n", emsg, rc);
1128 
1129 	/* clear SError */
1130 	tmp = readl(port_mmio + PORT_SCR_ERR);
1131 	VPRINTK("PORT_SCR_ERR 0x%x\n", tmp);
1132 	writel(tmp, port_mmio + PORT_SCR_ERR);
1133 
1134 	/* clear port IRQ */
1135 	tmp = readl(port_mmio + PORT_IRQ_STAT);
1136 	VPRINTK("PORT_IRQ_STAT 0x%x\n", tmp);
1137 	if (tmp)
1138 		writel(tmp, port_mmio + PORT_IRQ_STAT);
1139 
1140 	writel(1 << port_no, mmio + HOST_IRQ_STAT);
1141 }
1142 
1143 void ahci_init_controller(struct ata_host *host)
1144 {
1145 	struct ahci_host_priv *hpriv = host->private_data;
1146 	void __iomem *mmio = hpriv->mmio;
1147 	int i;
1148 	void __iomem *port_mmio;
1149 	u32 tmp;
1150 
1151 	for (i = 0; i < host->n_ports; i++) {
1152 		struct ata_port *ap = host->ports[i];
1153 
1154 		port_mmio = ahci_port_base(ap);
1155 		if (ata_port_is_dummy(ap))
1156 			continue;
1157 
1158 		ahci_port_init(host->dev, ap, i, mmio, port_mmio);
1159 	}
1160 
1161 	tmp = readl(mmio + HOST_CTL);
1162 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1163 	writel(tmp | HOST_IRQ_EN, mmio + HOST_CTL);
1164 	tmp = readl(mmio + HOST_CTL);
1165 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1166 }
1167 EXPORT_SYMBOL_GPL(ahci_init_controller);
1168 
1169 static void ahci_dev_config(struct ata_device *dev)
1170 {
1171 	struct ahci_host_priv *hpriv = dev->link->ap->host->private_data;
1172 
1173 	if (hpriv->flags & AHCI_HFLAG_SECT255) {
1174 		dev->max_sectors = 255;
1175 		ata_dev_info(dev,
1176 			     "SB600 AHCI: limiting to 255 sectors per cmd\n");
1177 	}
1178 }
1179 
1180 unsigned int ahci_dev_classify(struct ata_port *ap)
1181 {
1182 	void __iomem *port_mmio = ahci_port_base(ap);
1183 	struct ata_taskfile tf;
1184 	u32 tmp;
1185 
1186 	tmp = readl(port_mmio + PORT_SIG);
1187 	tf.lbah		= (tmp >> 24)	& 0xff;
1188 	tf.lbam		= (tmp >> 16)	& 0xff;
1189 	tf.lbal		= (tmp >> 8)	& 0xff;
1190 	tf.nsect	= (tmp)		& 0xff;
1191 
1192 	return ata_dev_classify(&tf);
1193 }
1194 EXPORT_SYMBOL_GPL(ahci_dev_classify);
1195 
1196 void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
1197 			u32 opts)
1198 {
1199 	dma_addr_t cmd_tbl_dma;
1200 
1201 	cmd_tbl_dma = pp->cmd_tbl_dma + tag * AHCI_CMD_TBL_SZ;
1202 
1203 	pp->cmd_slot[tag].opts = cpu_to_le32(opts);
1204 	pp->cmd_slot[tag].status = 0;
1205 	pp->cmd_slot[tag].tbl_addr = cpu_to_le32(cmd_tbl_dma & 0xffffffff);
1206 	pp->cmd_slot[tag].tbl_addr_hi = cpu_to_le32((cmd_tbl_dma >> 16) >> 16);
1207 }
1208 EXPORT_SYMBOL_GPL(ahci_fill_cmd_slot);
1209 
1210 int ahci_kick_engine(struct ata_port *ap)
1211 {
1212 	void __iomem *port_mmio = ahci_port_base(ap);
1213 	struct ahci_host_priv *hpriv = ap->host->private_data;
1214 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1215 	u32 tmp;
1216 	int busy, rc;
1217 
1218 	/* stop engine */
1219 	rc = ahci_stop_engine(ap);
1220 	if (rc)
1221 		goto out_restart;
1222 
1223 	/* need to do CLO?
1224 	 * always do CLO if PMP is attached (AHCI-1.3 9.2)
1225 	 */
1226 	busy = status & (ATA_BUSY | ATA_DRQ);
1227 	if (!busy && !sata_pmp_attached(ap)) {
1228 		rc = 0;
1229 		goto out_restart;
1230 	}
1231 
1232 	if (!(hpriv->cap & HOST_CAP_CLO)) {
1233 		rc = -EOPNOTSUPP;
1234 		goto out_restart;
1235 	}
1236 
1237 	/* perform CLO */
1238 	tmp = readl(port_mmio + PORT_CMD);
1239 	tmp |= PORT_CMD_CLO;
1240 	writel(tmp, port_mmio + PORT_CMD);
1241 
1242 	rc = 0;
1243 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
1244 				PORT_CMD_CLO, PORT_CMD_CLO, 1, 500);
1245 	if (tmp & PORT_CMD_CLO)
1246 		rc = -EIO;
1247 
1248 	/* restart engine */
1249  out_restart:
1250 	hpriv->start_engine(ap);
1251 	return rc;
1252 }
1253 EXPORT_SYMBOL_GPL(ahci_kick_engine);
1254 
1255 static int ahci_exec_polled_cmd(struct ata_port *ap, int pmp,
1256 				struct ata_taskfile *tf, int is_cmd, u16 flags,
1257 				unsigned long timeout_msec)
1258 {
1259 	const u32 cmd_fis_len = 5; /* five dwords */
1260 	struct ahci_port_priv *pp = ap->private_data;
1261 	void __iomem *port_mmio = ahci_port_base(ap);
1262 	u8 *fis = pp->cmd_tbl;
1263 	u32 tmp;
1264 
1265 	/* prep the command */
1266 	ata_tf_to_fis(tf, pmp, is_cmd, fis);
1267 	ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12));
1268 
1269 	/* issue & wait */
1270 	writel(1, port_mmio + PORT_CMD_ISSUE);
1271 
1272 	if (timeout_msec) {
1273 		tmp = ata_wait_register(ap, port_mmio + PORT_CMD_ISSUE,
1274 					0x1, 0x1, 1, timeout_msec);
1275 		if (tmp & 0x1) {
1276 			ahci_kick_engine(ap);
1277 			return -EBUSY;
1278 		}
1279 	} else
1280 		readl(port_mmio + PORT_CMD_ISSUE);	/* flush */
1281 
1282 	return 0;
1283 }
1284 
1285 int ahci_do_softreset(struct ata_link *link, unsigned int *class,
1286 		      int pmp, unsigned long deadline,
1287 		      int (*check_ready)(struct ata_link *link))
1288 {
1289 	struct ata_port *ap = link->ap;
1290 	struct ahci_host_priv *hpriv = ap->host->private_data;
1291 	struct ahci_port_priv *pp = ap->private_data;
1292 	const char *reason = NULL;
1293 	unsigned long now, msecs;
1294 	struct ata_taskfile tf;
1295 	bool fbs_disabled = false;
1296 	int rc;
1297 
1298 	DPRINTK("ENTER\n");
1299 
1300 	/* prepare for SRST (AHCI-1.1 10.4.1) */
1301 	rc = ahci_kick_engine(ap);
1302 	if (rc && rc != -EOPNOTSUPP)
1303 		ata_link_warn(link, "failed to reset engine (errno=%d)\n", rc);
1304 
1305 	/*
1306 	 * According to AHCI-1.2 9.3.9: if FBS is enable, software shall
1307 	 * clear PxFBS.EN to '0' prior to issuing software reset to devices
1308 	 * that is attached to port multiplier.
1309 	 */
1310 	if (!ata_is_host_link(link) && pp->fbs_enabled) {
1311 		ahci_disable_fbs(ap);
1312 		fbs_disabled = true;
1313 	}
1314 
1315 	ata_tf_init(link->device, &tf);
1316 
1317 	/* issue the first D2H Register FIS */
1318 	msecs = 0;
1319 	now = jiffies;
1320 	if (time_after(deadline, now))
1321 		msecs = jiffies_to_msecs(deadline - now);
1322 
1323 	tf.ctl |= ATA_SRST;
1324 	if (ahci_exec_polled_cmd(ap, pmp, &tf, 0,
1325 				 AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY, msecs)) {
1326 		rc = -EIO;
1327 		reason = "1st FIS failed";
1328 		goto fail;
1329 	}
1330 
1331 	/* spec says at least 5us, but be generous and sleep for 1ms */
1332 	ata_msleep(ap, 1);
1333 
1334 	/* issue the second D2H Register FIS */
1335 	tf.ctl &= ~ATA_SRST;
1336 	ahci_exec_polled_cmd(ap, pmp, &tf, 0, 0, 0);
1337 
1338 	/* wait for link to become ready */
1339 	rc = ata_wait_after_reset(link, deadline, check_ready);
1340 	if (rc == -EBUSY && hpriv->flags & AHCI_HFLAG_SRST_TOUT_IS_OFFLINE) {
1341 		/*
1342 		 * Workaround for cases where link online status can't
1343 		 * be trusted.  Treat device readiness timeout as link
1344 		 * offline.
1345 		 */
1346 		ata_link_info(link, "device not ready, treating as offline\n");
1347 		*class = ATA_DEV_NONE;
1348 	} else if (rc) {
1349 		/* link occupied, -ENODEV too is an error */
1350 		reason = "device not ready";
1351 		goto fail;
1352 	} else
1353 		*class = ahci_dev_classify(ap);
1354 
1355 	/* re-enable FBS if disabled before */
1356 	if (fbs_disabled)
1357 		ahci_enable_fbs(ap);
1358 
1359 	DPRINTK("EXIT, class=%u\n", *class);
1360 	return 0;
1361 
1362  fail:
1363 	ata_link_err(link, "softreset failed (%s)\n", reason);
1364 	return rc;
1365 }
1366 
1367 int ahci_check_ready(struct ata_link *link)
1368 {
1369 	void __iomem *port_mmio = ahci_port_base(link->ap);
1370 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1371 
1372 	return ata_check_ready(status);
1373 }
1374 EXPORT_SYMBOL_GPL(ahci_check_ready);
1375 
1376 static int ahci_softreset(struct ata_link *link, unsigned int *class,
1377 			  unsigned long deadline)
1378 {
1379 	int pmp = sata_srst_pmp(link);
1380 
1381 	DPRINTK("ENTER\n");
1382 
1383 	return ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
1384 }
1385 EXPORT_SYMBOL_GPL(ahci_do_softreset);
1386 
1387 static int ahci_bad_pmp_check_ready(struct ata_link *link)
1388 {
1389 	void __iomem *port_mmio = ahci_port_base(link->ap);
1390 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1391 	u32 irq_status = readl(port_mmio + PORT_IRQ_STAT);
1392 
1393 	/*
1394 	 * There is no need to check TFDATA if BAD PMP is found due to HW bug,
1395 	 * which can save timeout delay.
1396 	 */
1397 	if (irq_status & PORT_IRQ_BAD_PMP)
1398 		return -EIO;
1399 
1400 	return ata_check_ready(status);
1401 }
1402 
1403 static int ahci_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
1404 				    unsigned long deadline)
1405 {
1406 	struct ata_port *ap = link->ap;
1407 	void __iomem *port_mmio = ahci_port_base(ap);
1408 	int pmp = sata_srst_pmp(link);
1409 	int rc;
1410 	u32 irq_sts;
1411 
1412 	DPRINTK("ENTER\n");
1413 
1414 	rc = ahci_do_softreset(link, class, pmp, deadline,
1415 			       ahci_bad_pmp_check_ready);
1416 
1417 	/*
1418 	 * Soft reset fails with IPMS set when PMP is enabled but
1419 	 * SATA HDD/ODD is connected to SATA port, do soft reset
1420 	 * again to port 0.
1421 	 */
1422 	if (rc == -EIO) {
1423 		irq_sts = readl(port_mmio + PORT_IRQ_STAT);
1424 		if (irq_sts & PORT_IRQ_BAD_PMP) {
1425 			ata_link_warn(link,
1426 					"applying PMP SRST workaround "
1427 					"and retrying\n");
1428 			rc = ahci_do_softreset(link, class, 0, deadline,
1429 					       ahci_check_ready);
1430 		}
1431 	}
1432 
1433 	return rc;
1434 }
1435 
1436 static int ahci_hardreset(struct ata_link *link, unsigned int *class,
1437 			  unsigned long deadline)
1438 {
1439 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
1440 	struct ata_port *ap = link->ap;
1441 	struct ahci_port_priv *pp = ap->private_data;
1442 	struct ahci_host_priv *hpriv = ap->host->private_data;
1443 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
1444 	struct ata_taskfile tf;
1445 	bool online;
1446 	int rc;
1447 
1448 	DPRINTK("ENTER\n");
1449 
1450 	ahci_stop_engine(ap);
1451 
1452 	/* clear D2H reception area to properly wait for D2H FIS */
1453 	ata_tf_init(link->device, &tf);
1454 	tf.command = ATA_BUSY;
1455 	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
1456 
1457 	rc = sata_link_hardreset(link, timing, deadline, &online,
1458 				 ahci_check_ready);
1459 
1460 	hpriv->start_engine(ap);
1461 
1462 	if (online)
1463 		*class = ahci_dev_classify(ap);
1464 
1465 	DPRINTK("EXIT, rc=%d, class=%u\n", rc, *class);
1466 	return rc;
1467 }
1468 
1469 static void ahci_postreset(struct ata_link *link, unsigned int *class)
1470 {
1471 	struct ata_port *ap = link->ap;
1472 	void __iomem *port_mmio = ahci_port_base(ap);
1473 	u32 new_tmp, tmp;
1474 
1475 	ata_std_postreset(link, class);
1476 
1477 	/* Make sure port's ATAPI bit is set appropriately */
1478 	new_tmp = tmp = readl(port_mmio + PORT_CMD);
1479 	if (*class == ATA_DEV_ATAPI)
1480 		new_tmp |= PORT_CMD_ATAPI;
1481 	else
1482 		new_tmp &= ~PORT_CMD_ATAPI;
1483 	if (new_tmp != tmp) {
1484 		writel(new_tmp, port_mmio + PORT_CMD);
1485 		readl(port_mmio + PORT_CMD); /* flush */
1486 	}
1487 }
1488 
1489 static unsigned int ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl)
1490 {
1491 	struct scatterlist *sg;
1492 	struct ahci_sg *ahci_sg = cmd_tbl + AHCI_CMD_TBL_HDR_SZ;
1493 	unsigned int si;
1494 
1495 	VPRINTK("ENTER\n");
1496 
1497 	/*
1498 	 * Next, the S/G list.
1499 	 */
1500 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
1501 		dma_addr_t addr = sg_dma_address(sg);
1502 		u32 sg_len = sg_dma_len(sg);
1503 
1504 		ahci_sg[si].addr = cpu_to_le32(addr & 0xffffffff);
1505 		ahci_sg[si].addr_hi = cpu_to_le32((addr >> 16) >> 16);
1506 		ahci_sg[si].flags_size = cpu_to_le32(sg_len - 1);
1507 	}
1508 
1509 	return si;
1510 }
1511 
1512 static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc)
1513 {
1514 	struct ata_port *ap = qc->ap;
1515 	struct ahci_port_priv *pp = ap->private_data;
1516 
1517 	if (!sata_pmp_attached(ap) || pp->fbs_enabled)
1518 		return ata_std_qc_defer(qc);
1519 	else
1520 		return sata_pmp_qc_defer_cmd_switch(qc);
1521 }
1522 
1523 static void ahci_qc_prep(struct ata_queued_cmd *qc)
1524 {
1525 	struct ata_port *ap = qc->ap;
1526 	struct ahci_port_priv *pp = ap->private_data;
1527 	int is_atapi = ata_is_atapi(qc->tf.protocol);
1528 	void *cmd_tbl;
1529 	u32 opts;
1530 	const u32 cmd_fis_len = 5; /* five dwords */
1531 	unsigned int n_elem;
1532 
1533 	/*
1534 	 * Fill in command table information.  First, the header,
1535 	 * a SATA Register - Host to Device command FIS.
1536 	 */
1537 	cmd_tbl = pp->cmd_tbl + qc->tag * AHCI_CMD_TBL_SZ;
1538 
1539 	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, cmd_tbl);
1540 	if (is_atapi) {
1541 		memset(cmd_tbl + AHCI_CMD_TBL_CDB, 0, 32);
1542 		memcpy(cmd_tbl + AHCI_CMD_TBL_CDB, qc->cdb, qc->dev->cdb_len);
1543 	}
1544 
1545 	n_elem = 0;
1546 	if (qc->flags & ATA_QCFLAG_DMAMAP)
1547 		n_elem = ahci_fill_sg(qc, cmd_tbl);
1548 
1549 	/*
1550 	 * Fill in command slot information.
1551 	 */
1552 	opts = cmd_fis_len | n_elem << 16 | (qc->dev->link->pmp << 12);
1553 	if (qc->tf.flags & ATA_TFLAG_WRITE)
1554 		opts |= AHCI_CMD_WRITE;
1555 	if (is_atapi)
1556 		opts |= AHCI_CMD_ATAPI | AHCI_CMD_PREFETCH;
1557 
1558 	ahci_fill_cmd_slot(pp, qc->tag, opts);
1559 }
1560 
1561 static void ahci_fbs_dec_intr(struct ata_port *ap)
1562 {
1563 	struct ahci_port_priv *pp = ap->private_data;
1564 	void __iomem *port_mmio = ahci_port_base(ap);
1565 	u32 fbs = readl(port_mmio + PORT_FBS);
1566 	int retries = 3;
1567 
1568 	DPRINTK("ENTER\n");
1569 	BUG_ON(!pp->fbs_enabled);
1570 
1571 	/* time to wait for DEC is not specified by AHCI spec,
1572 	 * add a retry loop for safety.
1573 	 */
1574 	writel(fbs | PORT_FBS_DEC, port_mmio + PORT_FBS);
1575 	fbs = readl(port_mmio + PORT_FBS);
1576 	while ((fbs & PORT_FBS_DEC) && retries--) {
1577 		udelay(1);
1578 		fbs = readl(port_mmio + PORT_FBS);
1579 	}
1580 
1581 	if (fbs & PORT_FBS_DEC)
1582 		dev_err(ap->host->dev, "failed to clear device error\n");
1583 }
1584 
1585 static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
1586 {
1587 	struct ahci_host_priv *hpriv = ap->host->private_data;
1588 	struct ahci_port_priv *pp = ap->private_data;
1589 	struct ata_eh_info *host_ehi = &ap->link.eh_info;
1590 	struct ata_link *link = NULL;
1591 	struct ata_queued_cmd *active_qc;
1592 	struct ata_eh_info *active_ehi;
1593 	bool fbs_need_dec = false;
1594 	u32 serror;
1595 
1596 	/* determine active link with error */
1597 	if (pp->fbs_enabled) {
1598 		void __iomem *port_mmio = ahci_port_base(ap);
1599 		u32 fbs = readl(port_mmio + PORT_FBS);
1600 		int pmp = fbs >> PORT_FBS_DWE_OFFSET;
1601 
1602 		if ((fbs & PORT_FBS_SDE) && (pmp < ap->nr_pmp_links)) {
1603 			link = &ap->pmp_link[pmp];
1604 			fbs_need_dec = true;
1605 		}
1606 
1607 	} else
1608 		ata_for_each_link(link, ap, EDGE)
1609 			if (ata_link_active(link))
1610 				break;
1611 
1612 	if (!link)
1613 		link = &ap->link;
1614 
1615 	active_qc = ata_qc_from_tag(ap, link->active_tag);
1616 	active_ehi = &link->eh_info;
1617 
1618 	/* record irq stat */
1619 	ata_ehi_clear_desc(host_ehi);
1620 	ata_ehi_push_desc(host_ehi, "irq_stat 0x%08x", irq_stat);
1621 
1622 	/* AHCI needs SError cleared; otherwise, it might lock up */
1623 	ahci_scr_read(&ap->link, SCR_ERROR, &serror);
1624 	ahci_scr_write(&ap->link, SCR_ERROR, serror);
1625 	host_ehi->serror |= serror;
1626 
1627 	/* some controllers set IRQ_IF_ERR on device errors, ignore it */
1628 	if (hpriv->flags & AHCI_HFLAG_IGN_IRQ_IF_ERR)
1629 		irq_stat &= ~PORT_IRQ_IF_ERR;
1630 
1631 	if (irq_stat & PORT_IRQ_TF_ERR) {
1632 		/* If qc is active, charge it; otherwise, the active
1633 		 * link.  There's no active qc on NCQ errors.  It will
1634 		 * be determined by EH by reading log page 10h.
1635 		 */
1636 		if (active_qc)
1637 			active_qc->err_mask |= AC_ERR_DEV;
1638 		else
1639 			active_ehi->err_mask |= AC_ERR_DEV;
1640 
1641 		if (hpriv->flags & AHCI_HFLAG_IGN_SERR_INTERNAL)
1642 			host_ehi->serror &= ~SERR_INTERNAL;
1643 	}
1644 
1645 	if (irq_stat & PORT_IRQ_UNK_FIS) {
1646 		u32 *unk = pp->rx_fis + RX_FIS_UNK;
1647 
1648 		active_ehi->err_mask |= AC_ERR_HSM;
1649 		active_ehi->action |= ATA_EH_RESET;
1650 		ata_ehi_push_desc(active_ehi,
1651 				  "unknown FIS %08x %08x %08x %08x" ,
1652 				  unk[0], unk[1], unk[2], unk[3]);
1653 	}
1654 
1655 	if (sata_pmp_attached(ap) && (irq_stat & PORT_IRQ_BAD_PMP)) {
1656 		active_ehi->err_mask |= AC_ERR_HSM;
1657 		active_ehi->action |= ATA_EH_RESET;
1658 		ata_ehi_push_desc(active_ehi, "incorrect PMP");
1659 	}
1660 
1661 	if (irq_stat & (PORT_IRQ_HBUS_ERR | PORT_IRQ_HBUS_DATA_ERR)) {
1662 		host_ehi->err_mask |= AC_ERR_HOST_BUS;
1663 		host_ehi->action |= ATA_EH_RESET;
1664 		ata_ehi_push_desc(host_ehi, "host bus error");
1665 	}
1666 
1667 	if (irq_stat & PORT_IRQ_IF_ERR) {
1668 		if (fbs_need_dec)
1669 			active_ehi->err_mask |= AC_ERR_DEV;
1670 		else {
1671 			host_ehi->err_mask |= AC_ERR_ATA_BUS;
1672 			host_ehi->action |= ATA_EH_RESET;
1673 		}
1674 
1675 		ata_ehi_push_desc(host_ehi, "interface fatal error");
1676 	}
1677 
1678 	if (irq_stat & (PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)) {
1679 		ata_ehi_hotplugged(host_ehi);
1680 		ata_ehi_push_desc(host_ehi, "%s",
1681 			irq_stat & PORT_IRQ_CONNECT ?
1682 			"connection status changed" : "PHY RDY changed");
1683 	}
1684 
1685 	/* okay, let's hand over to EH */
1686 
1687 	if (irq_stat & PORT_IRQ_FREEZE)
1688 		ata_port_freeze(ap);
1689 	else if (fbs_need_dec) {
1690 		ata_link_abort(link);
1691 		ahci_fbs_dec_intr(ap);
1692 	} else
1693 		ata_port_abort(ap);
1694 }
1695 
1696 static void ahci_handle_port_interrupt(struct ata_port *ap,
1697 				       void __iomem *port_mmio, u32 status)
1698 {
1699 	struct ata_eh_info *ehi = &ap->link.eh_info;
1700 	struct ahci_port_priv *pp = ap->private_data;
1701 	struct ahci_host_priv *hpriv = ap->host->private_data;
1702 	int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
1703 	u32 qc_active = 0;
1704 	int rc;
1705 
1706 	/* ignore BAD_PMP while resetting */
1707 	if (unlikely(resetting))
1708 		status &= ~PORT_IRQ_BAD_PMP;
1709 
1710 	if (sata_lpm_ignore_phy_events(&ap->link)) {
1711 		status &= ~PORT_IRQ_PHYRDY;
1712 		ahci_scr_write(&ap->link, SCR_ERROR, SERR_PHYRDY_CHG);
1713 	}
1714 
1715 	if (unlikely(status & PORT_IRQ_ERROR)) {
1716 		ahci_error_intr(ap, status);
1717 		return;
1718 	}
1719 
1720 	if (status & PORT_IRQ_SDB_FIS) {
1721 		/* If SNotification is available, leave notification
1722 		 * handling to sata_async_notification().  If not,
1723 		 * emulate it by snooping SDB FIS RX area.
1724 		 *
1725 		 * Snooping FIS RX area is probably cheaper than
1726 		 * poking SNotification but some constrollers which
1727 		 * implement SNotification, ICH9 for example, don't
1728 		 * store AN SDB FIS into receive area.
1729 		 */
1730 		if (hpriv->cap & HOST_CAP_SNTF)
1731 			sata_async_notification(ap);
1732 		else {
1733 			/* If the 'N' bit in word 0 of the FIS is set,
1734 			 * we just received asynchronous notification.
1735 			 * Tell libata about it.
1736 			 *
1737 			 * Lack of SNotification should not appear in
1738 			 * ahci 1.2, so the workaround is unnecessary
1739 			 * when FBS is enabled.
1740 			 */
1741 			if (pp->fbs_enabled)
1742 				WARN_ON_ONCE(1);
1743 			else {
1744 				const __le32 *f = pp->rx_fis + RX_FIS_SDB;
1745 				u32 f0 = le32_to_cpu(f[0]);
1746 				if (f0 & (1 << 15))
1747 					sata_async_notification(ap);
1748 			}
1749 		}
1750 	}
1751 
1752 	/* pp->active_link is not reliable once FBS is enabled, both
1753 	 * PORT_SCR_ACT and PORT_CMD_ISSUE should be checked because
1754 	 * NCQ and non-NCQ commands may be in flight at the same time.
1755 	 */
1756 	if (pp->fbs_enabled) {
1757 		if (ap->qc_active) {
1758 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1759 			qc_active |= readl(port_mmio + PORT_CMD_ISSUE);
1760 		}
1761 	} else {
1762 		/* pp->active_link is valid iff any command is in flight */
1763 		if (ap->qc_active && pp->active_link->sactive)
1764 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1765 		else
1766 			qc_active = readl(port_mmio + PORT_CMD_ISSUE);
1767 	}
1768 
1769 
1770 	rc = ata_qc_complete_multiple(ap, qc_active);
1771 
1772 	/* while resetting, invalid completions are expected */
1773 	if (unlikely(rc < 0 && !resetting)) {
1774 		ehi->err_mask |= AC_ERR_HSM;
1775 		ehi->action |= ATA_EH_RESET;
1776 		ata_port_freeze(ap);
1777 	}
1778 }
1779 
1780 static void ahci_port_intr(struct ata_port *ap)
1781 {
1782 	void __iomem *port_mmio = ahci_port_base(ap);
1783 	u32 status;
1784 
1785 	status = readl(port_mmio + PORT_IRQ_STAT);
1786 	writel(status, port_mmio + PORT_IRQ_STAT);
1787 
1788 	ahci_handle_port_interrupt(ap, port_mmio, status);
1789 }
1790 
1791 static irqreturn_t ahci_port_thread_fn(int irq, void *dev_instance)
1792 {
1793 	struct ata_port *ap = dev_instance;
1794 	struct ahci_port_priv *pp = ap->private_data;
1795 	void __iomem *port_mmio = ahci_port_base(ap);
1796 	u32 status;
1797 
1798 	status = atomic_xchg(&pp->intr_status, 0);
1799 	if (!status)
1800 		return IRQ_NONE;
1801 
1802 	spin_lock_bh(ap->lock);
1803 	ahci_handle_port_interrupt(ap, port_mmio, status);
1804 	spin_unlock_bh(ap->lock);
1805 
1806 	return IRQ_HANDLED;
1807 }
1808 
1809 static irqreturn_t ahci_multi_irqs_intr(int irq, void *dev_instance)
1810 {
1811 	struct ata_port *ap = dev_instance;
1812 	void __iomem *port_mmio = ahci_port_base(ap);
1813 	struct ahci_port_priv *pp = ap->private_data;
1814 	u32 status;
1815 
1816 	VPRINTK("ENTER\n");
1817 
1818 	status = readl(port_mmio + PORT_IRQ_STAT);
1819 	writel(status, port_mmio + PORT_IRQ_STAT);
1820 
1821 	atomic_or(status, &pp->intr_status);
1822 
1823 	VPRINTK("EXIT\n");
1824 
1825 	return IRQ_WAKE_THREAD;
1826 }
1827 
1828 static u32 ahci_handle_port_intr(struct ata_host *host, u32 irq_masked)
1829 {
1830 	unsigned int i, handled = 0;
1831 
1832 	for (i = 0; i < host->n_ports; i++) {
1833 		struct ata_port *ap;
1834 
1835 		if (!(irq_masked & (1 << i)))
1836 			continue;
1837 
1838 		ap = host->ports[i];
1839 		if (ap) {
1840 			ahci_port_intr(ap);
1841 			VPRINTK("port %u\n", i);
1842 		} else {
1843 			VPRINTK("port %u (no irq)\n", i);
1844 			if (ata_ratelimit())
1845 				dev_warn(host->dev,
1846 					 "interrupt on disabled port %u\n", i);
1847 		}
1848 
1849 		handled = 1;
1850 	}
1851 
1852 	return handled;
1853 }
1854 
1855 static irqreturn_t ahci_single_edge_irq_intr(int irq, void *dev_instance)
1856 {
1857 	struct ata_host *host = dev_instance;
1858 	struct ahci_host_priv *hpriv;
1859 	unsigned int rc = 0;
1860 	void __iomem *mmio;
1861 	u32 irq_stat, irq_masked;
1862 
1863 	VPRINTK("ENTER\n");
1864 
1865 	hpriv = host->private_data;
1866 	mmio = hpriv->mmio;
1867 
1868 	/* sigh.  0xffffffff is a valid return from h/w */
1869 	irq_stat = readl(mmio + HOST_IRQ_STAT);
1870 	if (!irq_stat)
1871 		return IRQ_NONE;
1872 
1873 	irq_masked = irq_stat & hpriv->port_map;
1874 
1875 	spin_lock(&host->lock);
1876 
1877 	/*
1878 	 * HOST_IRQ_STAT behaves as edge triggered latch meaning that
1879 	 * it should be cleared before all the port events are cleared.
1880 	 */
1881 	writel(irq_stat, mmio + HOST_IRQ_STAT);
1882 
1883 	rc = ahci_handle_port_intr(host, irq_masked);
1884 
1885 	spin_unlock(&host->lock);
1886 
1887 	VPRINTK("EXIT\n");
1888 
1889 	return IRQ_RETVAL(rc);
1890 }
1891 
1892 static irqreturn_t ahci_single_level_irq_intr(int irq, void *dev_instance)
1893 {
1894 	struct ata_host *host = dev_instance;
1895 	struct ahci_host_priv *hpriv;
1896 	unsigned int rc = 0;
1897 	void __iomem *mmio;
1898 	u32 irq_stat, irq_masked;
1899 
1900 	VPRINTK("ENTER\n");
1901 
1902 	hpriv = host->private_data;
1903 	mmio = hpriv->mmio;
1904 
1905 	/* sigh.  0xffffffff is a valid return from h/w */
1906 	irq_stat = readl(mmio + HOST_IRQ_STAT);
1907 	if (!irq_stat)
1908 		return IRQ_NONE;
1909 
1910 	irq_masked = irq_stat & hpriv->port_map;
1911 
1912 	spin_lock(&host->lock);
1913 
1914 	rc = ahci_handle_port_intr(host, irq_masked);
1915 
1916 	/* HOST_IRQ_STAT behaves as level triggered latch meaning that
1917 	 * it should be cleared after all the port events are cleared;
1918 	 * otherwise, it will raise a spurious interrupt after each
1919 	 * valid one.  Please read section 10.6.2 of ahci 1.1 for more
1920 	 * information.
1921 	 *
1922 	 * Also, use the unmasked value to clear interrupt as spurious
1923 	 * pending event on a dummy port might cause screaming IRQ.
1924 	 */
1925 	writel(irq_stat, mmio + HOST_IRQ_STAT);
1926 
1927 	spin_unlock(&host->lock);
1928 
1929 	VPRINTK("EXIT\n");
1930 
1931 	return IRQ_RETVAL(rc);
1932 }
1933 
1934 unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
1935 {
1936 	struct ata_port *ap = qc->ap;
1937 	void __iomem *port_mmio = ahci_port_base(ap);
1938 	struct ahci_port_priv *pp = ap->private_data;
1939 
1940 	/* Keep track of the currently active link.  It will be used
1941 	 * in completion path to determine whether NCQ phase is in
1942 	 * progress.
1943 	 */
1944 	pp->active_link = qc->dev->link;
1945 
1946 	if (qc->tf.protocol == ATA_PROT_NCQ)
1947 		writel(1 << qc->tag, port_mmio + PORT_SCR_ACT);
1948 
1949 	if (pp->fbs_enabled && pp->fbs_last_dev != qc->dev->link->pmp) {
1950 		u32 fbs = readl(port_mmio + PORT_FBS);
1951 		fbs &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC);
1952 		fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
1953 		writel(fbs, port_mmio + PORT_FBS);
1954 		pp->fbs_last_dev = qc->dev->link->pmp;
1955 	}
1956 
1957 	writel(1 << qc->tag, port_mmio + PORT_CMD_ISSUE);
1958 
1959 	ahci_sw_activity(qc->dev->link);
1960 
1961 	return 0;
1962 }
1963 EXPORT_SYMBOL_GPL(ahci_qc_issue);
1964 
1965 static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
1966 {
1967 	struct ahci_port_priv *pp = qc->ap->private_data;
1968 	u8 *rx_fis = pp->rx_fis;
1969 
1970 	if (pp->fbs_enabled)
1971 		rx_fis += qc->dev->link->pmp * AHCI_RX_FIS_SZ;
1972 
1973 	/*
1974 	 * After a successful execution of an ATA PIO data-in command,
1975 	 * the device doesn't send D2H Reg FIS to update the TF and
1976 	 * the host should take TF and E_Status from the preceding PIO
1977 	 * Setup FIS.
1978 	 */
1979 	if (qc->tf.protocol == ATA_PROT_PIO && qc->dma_dir == DMA_FROM_DEVICE &&
1980 	    !(qc->flags & ATA_QCFLAG_FAILED)) {
1981 		ata_tf_from_fis(rx_fis + RX_FIS_PIO_SETUP, &qc->result_tf);
1982 		qc->result_tf.command = (rx_fis + RX_FIS_PIO_SETUP)[15];
1983 	} else
1984 		ata_tf_from_fis(rx_fis + RX_FIS_D2H_REG, &qc->result_tf);
1985 
1986 	return true;
1987 }
1988 
1989 static void ahci_freeze(struct ata_port *ap)
1990 {
1991 	void __iomem *port_mmio = ahci_port_base(ap);
1992 
1993 	/* turn IRQ off */
1994 	writel(0, port_mmio + PORT_IRQ_MASK);
1995 }
1996 
1997 static void ahci_thaw(struct ata_port *ap)
1998 {
1999 	struct ahci_host_priv *hpriv = ap->host->private_data;
2000 	void __iomem *mmio = hpriv->mmio;
2001 	void __iomem *port_mmio = ahci_port_base(ap);
2002 	u32 tmp;
2003 	struct ahci_port_priv *pp = ap->private_data;
2004 
2005 	/* clear IRQ */
2006 	tmp = readl(port_mmio + PORT_IRQ_STAT);
2007 	writel(tmp, port_mmio + PORT_IRQ_STAT);
2008 	writel(1 << ap->port_no, mmio + HOST_IRQ_STAT);
2009 
2010 	/* turn IRQ back on */
2011 	writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
2012 }
2013 
2014 void ahci_error_handler(struct ata_port *ap)
2015 {
2016 	struct ahci_host_priv *hpriv = ap->host->private_data;
2017 
2018 	if (!(ap->pflags & ATA_PFLAG_FROZEN)) {
2019 		/* restart engine */
2020 		ahci_stop_engine(ap);
2021 		hpriv->start_engine(ap);
2022 	}
2023 
2024 	sata_pmp_error_handler(ap);
2025 
2026 	if (!ata_dev_enabled(ap->link.device))
2027 		ahci_stop_engine(ap);
2028 }
2029 EXPORT_SYMBOL_GPL(ahci_error_handler);
2030 
2031 static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
2032 {
2033 	struct ata_port *ap = qc->ap;
2034 
2035 	/* make DMA engine forget about the failed command */
2036 	if (qc->flags & ATA_QCFLAG_FAILED)
2037 		ahci_kick_engine(ap);
2038 }
2039 
2040 static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep)
2041 {
2042 	struct ahci_host_priv *hpriv = ap->host->private_data;
2043 	void __iomem *port_mmio = ahci_port_base(ap);
2044 	struct ata_device *dev = ap->link.device;
2045 	u32 devslp, dm, dito, mdat, deto;
2046 	int rc;
2047 	unsigned int err_mask;
2048 
2049 	devslp = readl(port_mmio + PORT_DEVSLP);
2050 	if (!(devslp & PORT_DEVSLP_DSP)) {
2051 		dev_info(ap->host->dev, "port does not support device sleep\n");
2052 		return;
2053 	}
2054 
2055 	/* disable device sleep */
2056 	if (!sleep) {
2057 		if (devslp & PORT_DEVSLP_ADSE) {
2058 			writel(devslp & ~PORT_DEVSLP_ADSE,
2059 			       port_mmio + PORT_DEVSLP);
2060 			err_mask = ata_dev_set_feature(dev,
2061 						       SETFEATURES_SATA_DISABLE,
2062 						       SATA_DEVSLP);
2063 			if (err_mask && err_mask != AC_ERR_DEV)
2064 				ata_dev_warn(dev, "failed to disable DEVSLP\n");
2065 		}
2066 		return;
2067 	}
2068 
2069 	/* device sleep was already enabled */
2070 	if (devslp & PORT_DEVSLP_ADSE)
2071 		return;
2072 
2073 	/* set DITO, MDAT, DETO and enable DevSlp, need to stop engine first */
2074 	rc = ahci_stop_engine(ap);
2075 	if (rc)
2076 		return;
2077 
2078 	dm = (devslp & PORT_DEVSLP_DM_MASK) >> PORT_DEVSLP_DM_OFFSET;
2079 	dito = devslp_idle_timeout / (dm + 1);
2080 	if (dito > 0x3ff)
2081 		dito = 0x3ff;
2082 
2083 	/* Use the nominal value 10 ms if the read MDAT is zero,
2084 	 * the nominal value of DETO is 20 ms.
2085 	 */
2086 	if (dev->devslp_timing[ATA_LOG_DEVSLP_VALID] &
2087 	    ATA_LOG_DEVSLP_VALID_MASK) {
2088 		mdat = dev->devslp_timing[ATA_LOG_DEVSLP_MDAT] &
2089 		       ATA_LOG_DEVSLP_MDAT_MASK;
2090 		if (!mdat)
2091 			mdat = 10;
2092 		deto = dev->devslp_timing[ATA_LOG_DEVSLP_DETO];
2093 		if (!deto)
2094 			deto = 20;
2095 	} else {
2096 		mdat = 10;
2097 		deto = 20;
2098 	}
2099 
2100 	devslp |= ((dito << PORT_DEVSLP_DITO_OFFSET) |
2101 		   (mdat << PORT_DEVSLP_MDAT_OFFSET) |
2102 		   (deto << PORT_DEVSLP_DETO_OFFSET) |
2103 		   PORT_DEVSLP_ADSE);
2104 	writel(devslp, port_mmio + PORT_DEVSLP);
2105 
2106 	hpriv->start_engine(ap);
2107 
2108 	/* enable device sleep feature for the drive */
2109 	err_mask = ata_dev_set_feature(dev,
2110 				       SETFEATURES_SATA_ENABLE,
2111 				       SATA_DEVSLP);
2112 	if (err_mask && err_mask != AC_ERR_DEV)
2113 		ata_dev_warn(dev, "failed to enable DEVSLP\n");
2114 }
2115 
2116 static void ahci_enable_fbs(struct ata_port *ap)
2117 {
2118 	struct ahci_host_priv *hpriv = ap->host->private_data;
2119 	struct ahci_port_priv *pp = ap->private_data;
2120 	void __iomem *port_mmio = ahci_port_base(ap);
2121 	u32 fbs;
2122 	int rc;
2123 
2124 	if (!pp->fbs_supported)
2125 		return;
2126 
2127 	fbs = readl(port_mmio + PORT_FBS);
2128 	if (fbs & PORT_FBS_EN) {
2129 		pp->fbs_enabled = true;
2130 		pp->fbs_last_dev = -1; /* initialization */
2131 		return;
2132 	}
2133 
2134 	rc = ahci_stop_engine(ap);
2135 	if (rc)
2136 		return;
2137 
2138 	writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
2139 	fbs = readl(port_mmio + PORT_FBS);
2140 	if (fbs & PORT_FBS_EN) {
2141 		dev_info(ap->host->dev, "FBS is enabled\n");
2142 		pp->fbs_enabled = true;
2143 		pp->fbs_last_dev = -1; /* initialization */
2144 	} else
2145 		dev_err(ap->host->dev, "Failed to enable FBS\n");
2146 
2147 	hpriv->start_engine(ap);
2148 }
2149 
2150 static void ahci_disable_fbs(struct ata_port *ap)
2151 {
2152 	struct ahci_host_priv *hpriv = ap->host->private_data;
2153 	struct ahci_port_priv *pp = ap->private_data;
2154 	void __iomem *port_mmio = ahci_port_base(ap);
2155 	u32 fbs;
2156 	int rc;
2157 
2158 	if (!pp->fbs_supported)
2159 		return;
2160 
2161 	fbs = readl(port_mmio + PORT_FBS);
2162 	if ((fbs & PORT_FBS_EN) == 0) {
2163 		pp->fbs_enabled = false;
2164 		return;
2165 	}
2166 
2167 	rc = ahci_stop_engine(ap);
2168 	if (rc)
2169 		return;
2170 
2171 	writel(fbs & ~PORT_FBS_EN, port_mmio + PORT_FBS);
2172 	fbs = readl(port_mmio + PORT_FBS);
2173 	if (fbs & PORT_FBS_EN)
2174 		dev_err(ap->host->dev, "Failed to disable FBS\n");
2175 	else {
2176 		dev_info(ap->host->dev, "FBS is disabled\n");
2177 		pp->fbs_enabled = false;
2178 	}
2179 
2180 	hpriv->start_engine(ap);
2181 }
2182 
2183 static void ahci_pmp_attach(struct ata_port *ap)
2184 {
2185 	void __iomem *port_mmio = ahci_port_base(ap);
2186 	struct ahci_port_priv *pp = ap->private_data;
2187 	u32 cmd;
2188 
2189 	cmd = readl(port_mmio + PORT_CMD);
2190 	cmd |= PORT_CMD_PMP;
2191 	writel(cmd, port_mmio + PORT_CMD);
2192 
2193 	ahci_enable_fbs(ap);
2194 
2195 	pp->intr_mask |= PORT_IRQ_BAD_PMP;
2196 
2197 	/*
2198 	 * We must not change the port interrupt mask register if the
2199 	 * port is marked frozen, the value in pp->intr_mask will be
2200 	 * restored later when the port is thawed.
2201 	 *
2202 	 * Note that during initialization, the port is marked as
2203 	 * frozen since the irq handler is not yet registered.
2204 	 */
2205 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
2206 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
2207 }
2208 
2209 static void ahci_pmp_detach(struct ata_port *ap)
2210 {
2211 	void __iomem *port_mmio = ahci_port_base(ap);
2212 	struct ahci_port_priv *pp = ap->private_data;
2213 	u32 cmd;
2214 
2215 	ahci_disable_fbs(ap);
2216 
2217 	cmd = readl(port_mmio + PORT_CMD);
2218 	cmd &= ~PORT_CMD_PMP;
2219 	writel(cmd, port_mmio + PORT_CMD);
2220 
2221 	pp->intr_mask &= ~PORT_IRQ_BAD_PMP;
2222 
2223 	/* see comment above in ahci_pmp_attach() */
2224 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
2225 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
2226 }
2227 
2228 int ahci_port_resume(struct ata_port *ap)
2229 {
2230 	ahci_power_up(ap);
2231 	ahci_start_port(ap);
2232 
2233 	if (sata_pmp_attached(ap))
2234 		ahci_pmp_attach(ap);
2235 	else
2236 		ahci_pmp_detach(ap);
2237 
2238 	return 0;
2239 }
2240 EXPORT_SYMBOL_GPL(ahci_port_resume);
2241 
2242 #ifdef CONFIG_PM
2243 static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg)
2244 {
2245 	const char *emsg = NULL;
2246 	int rc;
2247 
2248 	rc = ahci_deinit_port(ap, &emsg);
2249 	if (rc == 0)
2250 		ahci_power_down(ap);
2251 	else {
2252 		ata_port_err(ap, "%s (%d)\n", emsg, rc);
2253 		ata_port_freeze(ap);
2254 	}
2255 
2256 	return rc;
2257 }
2258 #endif
2259 
2260 static int ahci_port_start(struct ata_port *ap)
2261 {
2262 	struct ahci_host_priv *hpriv = ap->host->private_data;
2263 	struct device *dev = ap->host->dev;
2264 	struct ahci_port_priv *pp;
2265 	void *mem;
2266 	dma_addr_t mem_dma;
2267 	size_t dma_sz, rx_fis_sz;
2268 
2269 	pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
2270 	if (!pp)
2271 		return -ENOMEM;
2272 
2273 	if (ap->host->n_ports > 1) {
2274 		pp->irq_desc = devm_kzalloc(dev, 8, GFP_KERNEL);
2275 		if (!pp->irq_desc) {
2276 			devm_kfree(dev, pp);
2277 			return -ENOMEM;
2278 		}
2279 		snprintf(pp->irq_desc, 8,
2280 			 "%s%d", dev_driver_string(dev), ap->port_no);
2281 	}
2282 
2283 	/* check FBS capability */
2284 	if ((hpriv->cap & HOST_CAP_FBS) && sata_pmp_supported(ap)) {
2285 		void __iomem *port_mmio = ahci_port_base(ap);
2286 		u32 cmd = readl(port_mmio + PORT_CMD);
2287 		if (cmd & PORT_CMD_FBSCP)
2288 			pp->fbs_supported = true;
2289 		else if (hpriv->flags & AHCI_HFLAG_YES_FBS) {
2290 			dev_info(dev, "port %d can do FBS, forcing FBSCP\n",
2291 				 ap->port_no);
2292 			pp->fbs_supported = true;
2293 		} else
2294 			dev_warn(dev, "port %d is not capable of FBS\n",
2295 				 ap->port_no);
2296 	}
2297 
2298 	if (pp->fbs_supported) {
2299 		dma_sz = AHCI_PORT_PRIV_FBS_DMA_SZ;
2300 		rx_fis_sz = AHCI_RX_FIS_SZ * 16;
2301 	} else {
2302 		dma_sz = AHCI_PORT_PRIV_DMA_SZ;
2303 		rx_fis_sz = AHCI_RX_FIS_SZ;
2304 	}
2305 
2306 	mem = dmam_alloc_coherent(dev, dma_sz, &mem_dma, GFP_KERNEL);
2307 	if (!mem)
2308 		return -ENOMEM;
2309 	memset(mem, 0, dma_sz);
2310 
2311 	/*
2312 	 * First item in chunk of DMA memory: 32-slot command table,
2313 	 * 32 bytes each in size
2314 	 */
2315 	pp->cmd_slot = mem;
2316 	pp->cmd_slot_dma = mem_dma;
2317 
2318 	mem += AHCI_CMD_SLOT_SZ;
2319 	mem_dma += AHCI_CMD_SLOT_SZ;
2320 
2321 	/*
2322 	 * Second item: Received-FIS area
2323 	 */
2324 	pp->rx_fis = mem;
2325 	pp->rx_fis_dma = mem_dma;
2326 
2327 	mem += rx_fis_sz;
2328 	mem_dma += rx_fis_sz;
2329 
2330 	/*
2331 	 * Third item: data area for storing a single command
2332 	 * and its scatter-gather table
2333 	 */
2334 	pp->cmd_tbl = mem;
2335 	pp->cmd_tbl_dma = mem_dma;
2336 
2337 	/*
2338 	 * Save off initial list of interrupts to be enabled.
2339 	 * This could be changed later
2340 	 */
2341 	pp->intr_mask = DEF_PORT_IRQ;
2342 
2343 	/*
2344 	 * Switch to per-port locking in case each port has its own MSI vector.
2345 	 */
2346 	if (hpriv->flags & AHCI_HFLAG_MULTI_MSI) {
2347 		spin_lock_init(&pp->lock);
2348 		ap->lock = &pp->lock;
2349 	}
2350 
2351 	ap->private_data = pp;
2352 
2353 	/* engage engines, captain */
2354 	return ahci_port_resume(ap);
2355 }
2356 
2357 static void ahci_port_stop(struct ata_port *ap)
2358 {
2359 	const char *emsg = NULL;
2360 	int rc;
2361 
2362 	/* de-initialize port */
2363 	rc = ahci_deinit_port(ap, &emsg);
2364 	if (rc)
2365 		ata_port_warn(ap, "%s (%d)\n", emsg, rc);
2366 }
2367 
2368 void ahci_print_info(struct ata_host *host, const char *scc_s)
2369 {
2370 	struct ahci_host_priv *hpriv = host->private_data;
2371 	void __iomem *mmio = hpriv->mmio;
2372 	u32 vers, cap, cap2, impl, speed;
2373 	const char *speed_s;
2374 
2375 	vers = readl(mmio + HOST_VERSION);
2376 	cap = hpriv->cap;
2377 	cap2 = hpriv->cap2;
2378 	impl = hpriv->port_map;
2379 
2380 	speed = (cap >> 20) & 0xf;
2381 	if (speed == 1)
2382 		speed_s = "1.5";
2383 	else if (speed == 2)
2384 		speed_s = "3";
2385 	else if (speed == 3)
2386 		speed_s = "6";
2387 	else
2388 		speed_s = "?";
2389 
2390 	dev_info(host->dev,
2391 		"AHCI %02x%02x.%02x%02x "
2392 		"%u slots %u ports %s Gbps 0x%x impl %s mode\n"
2393 		,
2394 
2395 		(vers >> 24) & 0xff,
2396 		(vers >> 16) & 0xff,
2397 		(vers >> 8) & 0xff,
2398 		vers & 0xff,
2399 
2400 		((cap >> 8) & 0x1f) + 1,
2401 		(cap & 0x1f) + 1,
2402 		speed_s,
2403 		impl,
2404 		scc_s);
2405 
2406 	dev_info(host->dev,
2407 		"flags: "
2408 		"%s%s%s%s%s%s%s"
2409 		"%s%s%s%s%s%s%s"
2410 		"%s%s%s%s%s%s%s"
2411 		"%s%s\n"
2412 		,
2413 
2414 		cap & HOST_CAP_64 ? "64bit " : "",
2415 		cap & HOST_CAP_NCQ ? "ncq " : "",
2416 		cap & HOST_CAP_SNTF ? "sntf " : "",
2417 		cap & HOST_CAP_MPS ? "ilck " : "",
2418 		cap & HOST_CAP_SSS ? "stag " : "",
2419 		cap & HOST_CAP_ALPM ? "pm " : "",
2420 		cap & HOST_CAP_LED ? "led " : "",
2421 		cap & HOST_CAP_CLO ? "clo " : "",
2422 		cap & HOST_CAP_ONLY ? "only " : "",
2423 		cap & HOST_CAP_PMP ? "pmp " : "",
2424 		cap & HOST_CAP_FBS ? "fbs " : "",
2425 		cap & HOST_CAP_PIO_MULTI ? "pio " : "",
2426 		cap & HOST_CAP_SSC ? "slum " : "",
2427 		cap & HOST_CAP_PART ? "part " : "",
2428 		cap & HOST_CAP_CCC ? "ccc " : "",
2429 		cap & HOST_CAP_EMS ? "ems " : "",
2430 		cap & HOST_CAP_SXS ? "sxs " : "",
2431 		cap2 & HOST_CAP2_DESO ? "deso " : "",
2432 		cap2 & HOST_CAP2_SADM ? "sadm " : "",
2433 		cap2 & HOST_CAP2_SDS ? "sds " : "",
2434 		cap2 & HOST_CAP2_APST ? "apst " : "",
2435 		cap2 & HOST_CAP2_NVMHCI ? "nvmp " : "",
2436 		cap2 & HOST_CAP2_BOH ? "boh " : ""
2437 		);
2438 }
2439 EXPORT_SYMBOL_GPL(ahci_print_info);
2440 
2441 void ahci_set_em_messages(struct ahci_host_priv *hpriv,
2442 			  struct ata_port_info *pi)
2443 {
2444 	u8 messages;
2445 	void __iomem *mmio = hpriv->mmio;
2446 	u32 em_loc = readl(mmio + HOST_EM_LOC);
2447 	u32 em_ctl = readl(mmio + HOST_EM_CTL);
2448 
2449 	if (!ahci_em_messages || !(hpriv->cap & HOST_CAP_EMS))
2450 		return;
2451 
2452 	messages = (em_ctl & EM_CTRL_MSG_TYPE) >> 16;
2453 
2454 	if (messages) {
2455 		/* store em_loc */
2456 		hpriv->em_loc = ((em_loc >> 16) * 4);
2457 		hpriv->em_buf_sz = ((em_loc & 0xff) * 4);
2458 		hpriv->em_msg_type = messages;
2459 		pi->flags |= ATA_FLAG_EM;
2460 		if (!(em_ctl & EM_CTL_ALHD))
2461 			pi->flags |= ATA_FLAG_SW_ACTIVITY;
2462 	}
2463 }
2464 EXPORT_SYMBOL_GPL(ahci_set_em_messages);
2465 
2466 static int ahci_host_activate_multi_irqs(struct ata_host *host, int irq,
2467 					 struct scsi_host_template *sht)
2468 {
2469 	int i, rc;
2470 
2471 	rc = ata_host_start(host);
2472 	if (rc)
2473 		return rc;
2474 	/*
2475 	 * Requests IRQs according to AHCI-1.1 when multiple MSIs were
2476 	 * allocated. That is one MSI per port, starting from @irq.
2477 	 */
2478 	for (i = 0; i < host->n_ports; i++) {
2479 		struct ahci_port_priv *pp = host->ports[i]->private_data;
2480 
2481 		/* Do not receive interrupts sent by dummy ports */
2482 		if (!pp) {
2483 			disable_irq(irq + i);
2484 			continue;
2485 		}
2486 
2487 		rc = devm_request_threaded_irq(host->dev, irq + i,
2488 					       ahci_multi_irqs_intr,
2489 					       ahci_port_thread_fn, IRQF_SHARED,
2490 					       pp->irq_desc, host->ports[i]);
2491 		if (rc)
2492 			goto out_free_irqs;
2493 	}
2494 
2495 	for (i = 0; i < host->n_ports; i++)
2496 		ata_port_desc(host->ports[i], "irq %d", irq + i);
2497 
2498 	rc = ata_host_register(host, sht);
2499 	if (rc)
2500 		goto out_free_all_irqs;
2501 
2502 	return 0;
2503 
2504 out_free_all_irqs:
2505 	i = host->n_ports;
2506 out_free_irqs:
2507 	for (i--; i >= 0; i--)
2508 		devm_free_irq(host->dev, irq + i, host->ports[i]);
2509 
2510 	return rc;
2511 }
2512 
2513 /**
2514  *	ahci_host_activate - start AHCI host, request IRQs and register it
2515  *	@host: target ATA host
2516  *	@sht: scsi_host_template to use when registering the host
2517  *
2518  *	LOCKING:
2519  *	Inherited from calling layer (may sleep).
2520  *
2521  *	RETURNS:
2522  *	0 on success, -errno otherwise.
2523  */
2524 int ahci_host_activate(struct ata_host *host, struct scsi_host_template *sht)
2525 {
2526 	struct ahci_host_priv *hpriv = host->private_data;
2527 	int irq = hpriv->irq;
2528 	int rc;
2529 
2530 	if (hpriv->flags & AHCI_HFLAG_MULTI_MSI)
2531 		rc = ahci_host_activate_multi_irqs(host, irq, sht);
2532 	else if (hpriv->flags & AHCI_HFLAG_EDGE_IRQ)
2533 		rc = ata_host_activate(host, irq, ahci_single_edge_irq_intr,
2534 				       IRQF_SHARED, sht);
2535 	else
2536 		rc = ata_host_activate(host, irq, ahci_single_level_irq_intr,
2537 				       IRQF_SHARED, sht);
2538 	return rc;
2539 }
2540 EXPORT_SYMBOL_GPL(ahci_host_activate);
2541 
2542 MODULE_AUTHOR("Jeff Garzik");
2543 MODULE_DESCRIPTION("Common AHCI SATA low-level routines");
2544 MODULE_LICENSE("GPL");
2545