xref: /linux/drivers/ata/libahci.c (revision 12871a0bd67dd4db4418e1daafcd46e9d329ef10)
1 /*
2  *  libahci.c - Common AHCI SATA low-level routines
3  *
4  *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
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/init.h>
39 #include <linux/blkdev.h>
40 #include <linux/delay.h>
41 #include <linux/interrupt.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/device.h>
44 #include <scsi/scsi_host.h>
45 #include <scsi/scsi_cmnd.h>
46 #include <linux/libata.h>
47 #include "ahci.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 unsigned int ahci_qc_issue(struct ata_queued_cmd *qc);
72 static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc);
73 static int ahci_port_start(struct ata_port *ap);
74 static void ahci_port_stop(struct ata_port *ap);
75 static void ahci_qc_prep(struct ata_queued_cmd *qc);
76 static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc);
77 static void ahci_freeze(struct ata_port *ap);
78 static void ahci_thaw(struct ata_port *ap);
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_hardreset(struct ata_link *link, unsigned int *class,
86 			  unsigned long deadline);
87 static void ahci_postreset(struct ata_link *link, unsigned int *class);
88 static void ahci_error_handler(struct ata_port *ap);
89 static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
90 static void ahci_dev_config(struct ata_device *dev);
91 #ifdef CONFIG_PM
92 static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg);
93 #endif
94 static ssize_t ahci_activity_show(struct ata_device *dev, char *buf);
95 static ssize_t ahci_activity_store(struct ata_device *dev,
96 				   enum sw_activity val);
97 static void ahci_init_sw_activity(struct ata_link *link);
98 
99 static ssize_t ahci_show_host_caps(struct device *dev,
100 				   struct device_attribute *attr, char *buf);
101 static ssize_t ahci_show_host_cap2(struct device *dev,
102 				   struct device_attribute *attr, char *buf);
103 static ssize_t ahci_show_host_version(struct device *dev,
104 				      struct device_attribute *attr, char *buf);
105 static ssize_t ahci_show_port_cmd(struct device *dev,
106 				  struct device_attribute *attr, char *buf);
107 static ssize_t ahci_read_em_buffer(struct device *dev,
108 				   struct device_attribute *attr, char *buf);
109 static ssize_t ahci_store_em_buffer(struct device *dev,
110 				    struct device_attribute *attr,
111 				    const char *buf, size_t size);
112 static ssize_t ahci_show_em_supported(struct device *dev,
113 				      struct device_attribute *attr, char *buf);
114 
115 static DEVICE_ATTR(ahci_host_caps, S_IRUGO, ahci_show_host_caps, NULL);
116 static DEVICE_ATTR(ahci_host_cap2, S_IRUGO, ahci_show_host_cap2, NULL);
117 static DEVICE_ATTR(ahci_host_version, S_IRUGO, ahci_show_host_version, NULL);
118 static DEVICE_ATTR(ahci_port_cmd, S_IRUGO, ahci_show_port_cmd, NULL);
119 static DEVICE_ATTR(em_buffer, S_IWUSR | S_IRUGO,
120 		   ahci_read_em_buffer, ahci_store_em_buffer);
121 static DEVICE_ATTR(em_message_supported, S_IRUGO, ahci_show_em_supported, NULL);
122 
123 struct device_attribute *ahci_shost_attrs[] = {
124 	&dev_attr_link_power_management_policy,
125 	&dev_attr_em_message_type,
126 	&dev_attr_em_message,
127 	&dev_attr_ahci_host_caps,
128 	&dev_attr_ahci_host_cap2,
129 	&dev_attr_ahci_host_version,
130 	&dev_attr_ahci_port_cmd,
131 	&dev_attr_em_buffer,
132 	&dev_attr_em_message_supported,
133 	NULL
134 };
135 EXPORT_SYMBOL_GPL(ahci_shost_attrs);
136 
137 struct device_attribute *ahci_sdev_attrs[] = {
138 	&dev_attr_sw_activity,
139 	&dev_attr_unload_heads,
140 	NULL
141 };
142 EXPORT_SYMBOL_GPL(ahci_sdev_attrs);
143 
144 struct ata_port_operations ahci_ops = {
145 	.inherits		= &sata_pmp_port_ops,
146 
147 	.qc_defer		= ahci_pmp_qc_defer,
148 	.qc_prep		= ahci_qc_prep,
149 	.qc_issue		= ahci_qc_issue,
150 	.qc_fill_rtf		= ahci_qc_fill_rtf,
151 
152 	.freeze			= ahci_freeze,
153 	.thaw			= ahci_thaw,
154 	.softreset		= ahci_softreset,
155 	.hardreset		= ahci_hardreset,
156 	.postreset		= ahci_postreset,
157 	.pmp_softreset		= ahci_softreset,
158 	.error_handler		= ahci_error_handler,
159 	.post_internal_cmd	= ahci_post_internal_cmd,
160 	.dev_config		= ahci_dev_config,
161 
162 	.scr_read		= ahci_scr_read,
163 	.scr_write		= ahci_scr_write,
164 	.pmp_attach		= ahci_pmp_attach,
165 	.pmp_detach		= ahci_pmp_detach,
166 
167 	.set_lpm		= ahci_set_lpm,
168 	.em_show		= ahci_led_show,
169 	.em_store		= ahci_led_store,
170 	.sw_activity_show	= ahci_activity_show,
171 	.sw_activity_store	= ahci_activity_store,
172 #ifdef CONFIG_PM
173 	.port_suspend		= ahci_port_suspend,
174 	.port_resume		= ahci_port_resume,
175 #endif
176 	.port_start		= ahci_port_start,
177 	.port_stop		= ahci_port_stop,
178 };
179 EXPORT_SYMBOL_GPL(ahci_ops);
180 
181 int ahci_em_messages = 1;
182 EXPORT_SYMBOL_GPL(ahci_em_messages);
183 module_param(ahci_em_messages, int, 0444);
184 /* add other LED protocol types when they become supported */
185 MODULE_PARM_DESC(ahci_em_messages,
186 	"AHCI Enclosure Management Message control (0 = off, 1 = on)");
187 
188 static void ahci_enable_ahci(void __iomem *mmio)
189 {
190 	int i;
191 	u32 tmp;
192 
193 	/* turn on AHCI_EN */
194 	tmp = readl(mmio + HOST_CTL);
195 	if (tmp & HOST_AHCI_EN)
196 		return;
197 
198 	/* Some controllers need AHCI_EN to be written multiple times.
199 	 * Try a few times before giving up.
200 	 */
201 	for (i = 0; i < 5; i++) {
202 		tmp |= HOST_AHCI_EN;
203 		writel(tmp, mmio + HOST_CTL);
204 		tmp = readl(mmio + HOST_CTL);	/* flush && sanity check */
205 		if (tmp & HOST_AHCI_EN)
206 			return;
207 		msleep(10);
208 	}
209 
210 	WARN_ON(1);
211 }
212 
213 static ssize_t ahci_show_host_caps(struct device *dev,
214 				   struct device_attribute *attr, char *buf)
215 {
216 	struct Scsi_Host *shost = class_to_shost(dev);
217 	struct ata_port *ap = ata_shost_to_port(shost);
218 	struct ahci_host_priv *hpriv = ap->host->private_data;
219 
220 	return sprintf(buf, "%x\n", hpriv->cap);
221 }
222 
223 static ssize_t ahci_show_host_cap2(struct device *dev,
224 				   struct device_attribute *attr, char *buf)
225 {
226 	struct Scsi_Host *shost = class_to_shost(dev);
227 	struct ata_port *ap = ata_shost_to_port(shost);
228 	struct ahci_host_priv *hpriv = ap->host->private_data;
229 
230 	return sprintf(buf, "%x\n", hpriv->cap2);
231 }
232 
233 static ssize_t ahci_show_host_version(struct device *dev,
234 				   struct device_attribute *attr, char *buf)
235 {
236 	struct Scsi_Host *shost = class_to_shost(dev);
237 	struct ata_port *ap = ata_shost_to_port(shost);
238 	struct ahci_host_priv *hpriv = ap->host->private_data;
239 	void __iomem *mmio = hpriv->mmio;
240 
241 	return sprintf(buf, "%x\n", readl(mmio + HOST_VERSION));
242 }
243 
244 static ssize_t ahci_show_port_cmd(struct device *dev,
245 				  struct device_attribute *attr, char *buf)
246 {
247 	struct Scsi_Host *shost = class_to_shost(dev);
248 	struct ata_port *ap = ata_shost_to_port(shost);
249 	void __iomem *port_mmio = ahci_port_base(ap);
250 
251 	return sprintf(buf, "%x\n", readl(port_mmio + PORT_CMD));
252 }
253 
254 static ssize_t ahci_read_em_buffer(struct device *dev,
255 				   struct device_attribute *attr, char *buf)
256 {
257 	struct Scsi_Host *shost = class_to_shost(dev);
258 	struct ata_port *ap = ata_shost_to_port(shost);
259 	struct ahci_host_priv *hpriv = ap->host->private_data;
260 	void __iomem *mmio = hpriv->mmio;
261 	void __iomem *em_mmio = mmio + hpriv->em_loc;
262 	u32 em_ctl, msg;
263 	unsigned long flags;
264 	size_t count;
265 	int i;
266 
267 	spin_lock_irqsave(ap->lock, flags);
268 
269 	em_ctl = readl(mmio + HOST_EM_CTL);
270 	if (!(ap->flags & ATA_FLAG_EM) || em_ctl & EM_CTL_XMT ||
271 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO)) {
272 		spin_unlock_irqrestore(ap->lock, flags);
273 		return -EINVAL;
274 	}
275 
276 	if (!(em_ctl & EM_CTL_MR)) {
277 		spin_unlock_irqrestore(ap->lock, flags);
278 		return -EAGAIN;
279 	}
280 
281 	if (!(em_ctl & EM_CTL_SMB))
282 		em_mmio += hpriv->em_buf_sz;
283 
284 	count = hpriv->em_buf_sz;
285 
286 	/* the count should not be larger than PAGE_SIZE */
287 	if (count > PAGE_SIZE) {
288 		if (printk_ratelimit())
289 			ata_port_printk(ap, KERN_WARNING,
290 					"EM read buffer size too large: "
291 					"buffer size %u, page size %lu\n",
292 					hpriv->em_buf_sz, PAGE_SIZE);
293 		count = PAGE_SIZE;
294 	}
295 
296 	for (i = 0; i < count; i += 4) {
297 		msg = readl(em_mmio + i);
298 		buf[i] = msg & 0xff;
299 		buf[i + 1] = (msg >> 8) & 0xff;
300 		buf[i + 2] = (msg >> 16) & 0xff;
301 		buf[i + 3] = (msg >> 24) & 0xff;
302 	}
303 
304 	spin_unlock_irqrestore(ap->lock, flags);
305 
306 	return i;
307 }
308 
309 static ssize_t ahci_store_em_buffer(struct device *dev,
310 				    struct device_attribute *attr,
311 				    const char *buf, size_t size)
312 {
313 	struct Scsi_Host *shost = class_to_shost(dev);
314 	struct ata_port *ap = ata_shost_to_port(shost);
315 	struct ahci_host_priv *hpriv = ap->host->private_data;
316 	void __iomem *mmio = hpriv->mmio;
317 	void __iomem *em_mmio = mmio + hpriv->em_loc;
318 	const unsigned char *msg_buf = buf;
319 	u32 em_ctl, msg;
320 	unsigned long flags;
321 	int i;
322 
323 	/* check size validity */
324 	if (!(ap->flags & ATA_FLAG_EM) ||
325 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO) ||
326 	    size % 4 || size > hpriv->em_buf_sz)
327 		return -EINVAL;
328 
329 	spin_lock_irqsave(ap->lock, flags);
330 
331 	em_ctl = readl(mmio + HOST_EM_CTL);
332 	if (em_ctl & EM_CTL_TM) {
333 		spin_unlock_irqrestore(ap->lock, flags);
334 		return -EBUSY;
335 	}
336 
337 	for (i = 0; i < size; i += 4) {
338 		msg = msg_buf[i] | msg_buf[i + 1] << 8 |
339 		      msg_buf[i + 2] << 16 | msg_buf[i + 3] << 24;
340 		writel(msg, em_mmio + i);
341 	}
342 
343 	writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
344 
345 	spin_unlock_irqrestore(ap->lock, flags);
346 
347 	return size;
348 }
349 
350 static ssize_t ahci_show_em_supported(struct device *dev,
351 				      struct device_attribute *attr, char *buf)
352 {
353 	struct Scsi_Host *shost = class_to_shost(dev);
354 	struct ata_port *ap = ata_shost_to_port(shost);
355 	struct ahci_host_priv *hpriv = ap->host->private_data;
356 	void __iomem *mmio = hpriv->mmio;
357 	u32 em_ctl;
358 
359 	em_ctl = readl(mmio + HOST_EM_CTL);
360 
361 	return sprintf(buf, "%s%s%s%s\n",
362 		       em_ctl & EM_CTL_LED ? "led " : "",
363 		       em_ctl & EM_CTL_SAFTE ? "saf-te " : "",
364 		       em_ctl & EM_CTL_SES ? "ses-2 " : "",
365 		       em_ctl & EM_CTL_SGPIO ? "sgpio " : "");
366 }
367 
368 /**
369  *	ahci_save_initial_config - Save and fixup initial config values
370  *	@dev: target AHCI device
371  *	@hpriv: host private area to store config values
372  *	@force_port_map: force port map to a specified value
373  *	@mask_port_map: mask out particular bits from port map
374  *
375  *	Some registers containing configuration info might be setup by
376  *	BIOS and might be cleared on reset.  This function saves the
377  *	initial values of those registers into @hpriv such that they
378  *	can be restored after controller reset.
379  *
380  *	If inconsistent, config values are fixed up by this function.
381  *
382  *	LOCKING:
383  *	None.
384  */
385 void ahci_save_initial_config(struct device *dev,
386 			      struct ahci_host_priv *hpriv,
387 			      unsigned int force_port_map,
388 			      unsigned int mask_port_map)
389 {
390 	void __iomem *mmio = hpriv->mmio;
391 	u32 cap, cap2, vers, port_map;
392 	int i;
393 
394 	/* make sure AHCI mode is enabled before accessing CAP */
395 	ahci_enable_ahci(mmio);
396 
397 	/* Values prefixed with saved_ are written back to host after
398 	 * reset.  Values without are used for driver operation.
399 	 */
400 	hpriv->saved_cap = cap = readl(mmio + HOST_CAP);
401 	hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL);
402 
403 	/* CAP2 register is only defined for AHCI 1.2 and later */
404 	vers = readl(mmio + HOST_VERSION);
405 	if ((vers >> 16) > 1 ||
406 	   ((vers >> 16) == 1 && (vers & 0xFFFF) >= 0x200))
407 		hpriv->saved_cap2 = cap2 = readl(mmio + HOST_CAP2);
408 	else
409 		hpriv->saved_cap2 = cap2 = 0;
410 
411 	/* some chips have errata preventing 64bit use */
412 	if ((cap & HOST_CAP_64) && (hpriv->flags & AHCI_HFLAG_32BIT_ONLY)) {
413 		dev_printk(KERN_INFO, dev,
414 			   "controller can't do 64bit DMA, forcing 32bit\n");
415 		cap &= ~HOST_CAP_64;
416 	}
417 
418 	if ((cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_NO_NCQ)) {
419 		dev_printk(KERN_INFO, dev,
420 			   "controller can't do NCQ, turning off CAP_NCQ\n");
421 		cap &= ~HOST_CAP_NCQ;
422 	}
423 
424 	if (!(cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_YES_NCQ)) {
425 		dev_printk(KERN_INFO, dev,
426 			   "controller can do NCQ, turning on CAP_NCQ\n");
427 		cap |= HOST_CAP_NCQ;
428 	}
429 
430 	if ((cap & HOST_CAP_PMP) && (hpriv->flags & AHCI_HFLAG_NO_PMP)) {
431 		dev_printk(KERN_INFO, dev,
432 			   "controller can't do PMP, turning off CAP_PMP\n");
433 		cap &= ~HOST_CAP_PMP;
434 	}
435 
436 	if ((cap & HOST_CAP_SNTF) && (hpriv->flags & AHCI_HFLAG_NO_SNTF)) {
437 		dev_printk(KERN_INFO, dev,
438 			   "controller can't do SNTF, turning off CAP_SNTF\n");
439 		cap &= ~HOST_CAP_SNTF;
440 	}
441 
442 	if (!(cap & HOST_CAP_FBS) && (hpriv->flags & AHCI_HFLAG_YES_FBS)) {
443 		dev_printk(KERN_INFO, dev,
444 			   "controller can do FBS, turning on CAP_FBS\n");
445 		cap |= HOST_CAP_FBS;
446 	}
447 
448 	if (force_port_map && port_map != force_port_map) {
449 		dev_printk(KERN_INFO, dev, "forcing port_map 0x%x -> 0x%x\n",
450 			   port_map, force_port_map);
451 		port_map = force_port_map;
452 	}
453 
454 	if (mask_port_map) {
455 		dev_printk(KERN_ERR, dev, "masking port_map 0x%x -> 0x%x\n",
456 			   port_map,
457 			   port_map & mask_port_map);
458 		port_map &= mask_port_map;
459 	}
460 
461 	/* cross check port_map and cap.n_ports */
462 	if (port_map) {
463 		int map_ports = 0;
464 
465 		for (i = 0; i < AHCI_MAX_PORTS; i++)
466 			if (port_map & (1 << i))
467 				map_ports++;
468 
469 		/* If PI has more ports than n_ports, whine, clear
470 		 * port_map and let it be generated from n_ports.
471 		 */
472 		if (map_ports > ahci_nr_ports(cap)) {
473 			dev_printk(KERN_WARNING, dev,
474 				   "implemented port map (0x%x) contains more "
475 				   "ports than nr_ports (%u), using nr_ports\n",
476 				   port_map, ahci_nr_ports(cap));
477 			port_map = 0;
478 		}
479 	}
480 
481 	/* fabricate port_map from cap.nr_ports */
482 	if (!port_map) {
483 		port_map = (1 << ahci_nr_ports(cap)) - 1;
484 		dev_printk(KERN_WARNING, dev,
485 			   "forcing PORTS_IMPL to 0x%x\n", port_map);
486 
487 		/* write the fixed up value to the PI register */
488 		hpriv->saved_port_map = port_map;
489 	}
490 
491 	/* record values to use during operation */
492 	hpriv->cap = cap;
493 	hpriv->cap2 = cap2;
494 	hpriv->port_map = port_map;
495 }
496 EXPORT_SYMBOL_GPL(ahci_save_initial_config);
497 
498 /**
499  *	ahci_restore_initial_config - Restore initial config
500  *	@host: target ATA host
501  *
502  *	Restore initial config stored by ahci_save_initial_config().
503  *
504  *	LOCKING:
505  *	None.
506  */
507 static void ahci_restore_initial_config(struct ata_host *host)
508 {
509 	struct ahci_host_priv *hpriv = host->private_data;
510 	void __iomem *mmio = hpriv->mmio;
511 
512 	writel(hpriv->saved_cap, mmio + HOST_CAP);
513 	if (hpriv->saved_cap2)
514 		writel(hpriv->saved_cap2, mmio + HOST_CAP2);
515 	writel(hpriv->saved_port_map, mmio + HOST_PORTS_IMPL);
516 	(void) readl(mmio + HOST_PORTS_IMPL);	/* flush */
517 }
518 
519 static unsigned ahci_scr_offset(struct ata_port *ap, unsigned int sc_reg)
520 {
521 	static const int offset[] = {
522 		[SCR_STATUS]		= PORT_SCR_STAT,
523 		[SCR_CONTROL]		= PORT_SCR_CTL,
524 		[SCR_ERROR]		= PORT_SCR_ERR,
525 		[SCR_ACTIVE]		= PORT_SCR_ACT,
526 		[SCR_NOTIFICATION]	= PORT_SCR_NTF,
527 	};
528 	struct ahci_host_priv *hpriv = ap->host->private_data;
529 
530 	if (sc_reg < ARRAY_SIZE(offset) &&
531 	    (sc_reg != SCR_NOTIFICATION || (hpriv->cap & HOST_CAP_SNTF)))
532 		return offset[sc_reg];
533 	return 0;
534 }
535 
536 static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val)
537 {
538 	void __iomem *port_mmio = ahci_port_base(link->ap);
539 	int offset = ahci_scr_offset(link->ap, sc_reg);
540 
541 	if (offset) {
542 		*val = readl(port_mmio + offset);
543 		return 0;
544 	}
545 	return -EINVAL;
546 }
547 
548 static int ahci_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val)
549 {
550 	void __iomem *port_mmio = ahci_port_base(link->ap);
551 	int offset = ahci_scr_offset(link->ap, sc_reg);
552 
553 	if (offset) {
554 		writel(val, port_mmio + offset);
555 		return 0;
556 	}
557 	return -EINVAL;
558 }
559 
560 void ahci_start_engine(struct ata_port *ap)
561 {
562 	void __iomem *port_mmio = ahci_port_base(ap);
563 	u32 tmp;
564 
565 	/* start DMA */
566 	tmp = readl(port_mmio + PORT_CMD);
567 	tmp |= PORT_CMD_START;
568 	writel(tmp, port_mmio + PORT_CMD);
569 	readl(port_mmio + PORT_CMD); /* flush */
570 }
571 EXPORT_SYMBOL_GPL(ahci_start_engine);
572 
573 int ahci_stop_engine(struct ata_port *ap)
574 {
575 	void __iomem *port_mmio = ahci_port_base(ap);
576 	u32 tmp;
577 
578 	tmp = readl(port_mmio + PORT_CMD);
579 
580 	/* check if the HBA is idle */
581 	if ((tmp & (PORT_CMD_START | PORT_CMD_LIST_ON)) == 0)
582 		return 0;
583 
584 	/* setting HBA to idle */
585 	tmp &= ~PORT_CMD_START;
586 	writel(tmp, port_mmio + PORT_CMD);
587 
588 	/* wait for engine to stop. This could be as long as 500 msec */
589 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
590 				PORT_CMD_LIST_ON, PORT_CMD_LIST_ON, 1, 500);
591 	if (tmp & PORT_CMD_LIST_ON)
592 		return -EIO;
593 
594 	return 0;
595 }
596 EXPORT_SYMBOL_GPL(ahci_stop_engine);
597 
598 static void ahci_start_fis_rx(struct ata_port *ap)
599 {
600 	void __iomem *port_mmio = ahci_port_base(ap);
601 	struct ahci_host_priv *hpriv = ap->host->private_data;
602 	struct ahci_port_priv *pp = ap->private_data;
603 	u32 tmp;
604 
605 	/* set FIS registers */
606 	if (hpriv->cap & HOST_CAP_64)
607 		writel((pp->cmd_slot_dma >> 16) >> 16,
608 		       port_mmio + PORT_LST_ADDR_HI);
609 	writel(pp->cmd_slot_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);
610 
611 	if (hpriv->cap & HOST_CAP_64)
612 		writel((pp->rx_fis_dma >> 16) >> 16,
613 		       port_mmio + PORT_FIS_ADDR_HI);
614 	writel(pp->rx_fis_dma & 0xffffffff, port_mmio + PORT_FIS_ADDR);
615 
616 	/* enable FIS reception */
617 	tmp = readl(port_mmio + PORT_CMD);
618 	tmp |= PORT_CMD_FIS_RX;
619 	writel(tmp, port_mmio + PORT_CMD);
620 
621 	/* flush */
622 	readl(port_mmio + PORT_CMD);
623 }
624 
625 static int ahci_stop_fis_rx(struct ata_port *ap)
626 {
627 	void __iomem *port_mmio = ahci_port_base(ap);
628 	u32 tmp;
629 
630 	/* disable FIS reception */
631 	tmp = readl(port_mmio + PORT_CMD);
632 	tmp &= ~PORT_CMD_FIS_RX;
633 	writel(tmp, port_mmio + PORT_CMD);
634 
635 	/* wait for completion, spec says 500ms, give it 1000 */
636 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD, PORT_CMD_FIS_ON,
637 				PORT_CMD_FIS_ON, 10, 1000);
638 	if (tmp & PORT_CMD_FIS_ON)
639 		return -EBUSY;
640 
641 	return 0;
642 }
643 
644 static void ahci_power_up(struct ata_port *ap)
645 {
646 	struct ahci_host_priv *hpriv = ap->host->private_data;
647 	void __iomem *port_mmio = ahci_port_base(ap);
648 	u32 cmd;
649 
650 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
651 
652 	/* spin up device */
653 	if (hpriv->cap & HOST_CAP_SSS) {
654 		cmd |= PORT_CMD_SPIN_UP;
655 		writel(cmd, port_mmio + PORT_CMD);
656 	}
657 
658 	/* wake up link */
659 	writel(cmd | PORT_CMD_ICC_ACTIVE, port_mmio + PORT_CMD);
660 }
661 
662 static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
663 			unsigned int hints)
664 {
665 	struct ata_port *ap = link->ap;
666 	struct ahci_host_priv *hpriv = ap->host->private_data;
667 	struct ahci_port_priv *pp = ap->private_data;
668 	void __iomem *port_mmio = ahci_port_base(ap);
669 
670 	if (policy != ATA_LPM_MAX_POWER) {
671 		/*
672 		 * Disable interrupts on Phy Ready. This keeps us from
673 		 * getting woken up due to spurious phy ready
674 		 * interrupts.
675 		 */
676 		pp->intr_mask &= ~PORT_IRQ_PHYRDY;
677 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
678 
679 		sata_link_scr_lpm(link, policy, false);
680 	}
681 
682 	if (hpriv->cap & HOST_CAP_ALPM) {
683 		u32 cmd = readl(port_mmio + PORT_CMD);
684 
685 		if (policy == ATA_LPM_MAX_POWER || !(hints & ATA_LPM_HIPM)) {
686 			cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE);
687 			cmd |= PORT_CMD_ICC_ACTIVE;
688 
689 			writel(cmd, port_mmio + PORT_CMD);
690 			readl(port_mmio + PORT_CMD);
691 
692 			/* wait 10ms to be sure we've come out of LPM state */
693 			ata_msleep(ap, 10);
694 		} else {
695 			cmd |= PORT_CMD_ALPE;
696 			if (policy == ATA_LPM_MIN_POWER)
697 				cmd |= PORT_CMD_ASP;
698 
699 			/* write out new cmd value */
700 			writel(cmd, port_mmio + PORT_CMD);
701 		}
702 	}
703 
704 	if (policy == ATA_LPM_MAX_POWER) {
705 		sata_link_scr_lpm(link, policy, false);
706 
707 		/* turn PHYRDY IRQ back on */
708 		pp->intr_mask |= PORT_IRQ_PHYRDY;
709 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
710 	}
711 
712 	return 0;
713 }
714 
715 #ifdef CONFIG_PM
716 static void ahci_power_down(struct ata_port *ap)
717 {
718 	struct ahci_host_priv *hpriv = ap->host->private_data;
719 	void __iomem *port_mmio = ahci_port_base(ap);
720 	u32 cmd, scontrol;
721 
722 	if (!(hpriv->cap & HOST_CAP_SSS))
723 		return;
724 
725 	/* put device into listen mode, first set PxSCTL.DET to 0 */
726 	scontrol = readl(port_mmio + PORT_SCR_CTL);
727 	scontrol &= ~0xf;
728 	writel(scontrol, port_mmio + PORT_SCR_CTL);
729 
730 	/* then set PxCMD.SUD to 0 */
731 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
732 	cmd &= ~PORT_CMD_SPIN_UP;
733 	writel(cmd, port_mmio + PORT_CMD);
734 }
735 #endif
736 
737 static void ahci_start_port(struct ata_port *ap)
738 {
739 	struct ahci_port_priv *pp = ap->private_data;
740 	struct ata_link *link;
741 	struct ahci_em_priv *emp;
742 	ssize_t rc;
743 	int i;
744 
745 	/* enable FIS reception */
746 	ahci_start_fis_rx(ap);
747 
748 	/* enable DMA */
749 	ahci_start_engine(ap);
750 
751 	/* turn on LEDs */
752 	if (ap->flags & ATA_FLAG_EM) {
753 		ata_for_each_link(link, ap, EDGE) {
754 			emp = &pp->em_priv[link->pmp];
755 
756 			/* EM Transmit bit maybe busy during init */
757 			for (i = 0; i < EM_MAX_RETRY; i++) {
758 				rc = ahci_transmit_led_message(ap,
759 							       emp->led_state,
760 							       4);
761 				if (rc == -EBUSY)
762 					ata_msleep(ap, 1);
763 				else
764 					break;
765 			}
766 		}
767 	}
768 
769 	if (ap->flags & ATA_FLAG_SW_ACTIVITY)
770 		ata_for_each_link(link, ap, EDGE)
771 			ahci_init_sw_activity(link);
772 
773 }
774 
775 static int ahci_deinit_port(struct ata_port *ap, const char **emsg)
776 {
777 	int rc;
778 
779 	/* disable DMA */
780 	rc = ahci_stop_engine(ap);
781 	if (rc) {
782 		*emsg = "failed to stop engine";
783 		return rc;
784 	}
785 
786 	/* disable FIS reception */
787 	rc = ahci_stop_fis_rx(ap);
788 	if (rc) {
789 		*emsg = "failed stop FIS RX";
790 		return rc;
791 	}
792 
793 	return 0;
794 }
795 
796 int ahci_reset_controller(struct ata_host *host)
797 {
798 	struct ahci_host_priv *hpriv = host->private_data;
799 	void __iomem *mmio = hpriv->mmio;
800 	u32 tmp;
801 
802 	/* we must be in AHCI mode, before using anything
803 	 * AHCI-specific, such as HOST_RESET.
804 	 */
805 	ahci_enable_ahci(mmio);
806 
807 	/* global controller reset */
808 	if (!ahci_skip_host_reset) {
809 		tmp = readl(mmio + HOST_CTL);
810 		if ((tmp & HOST_RESET) == 0) {
811 			writel(tmp | HOST_RESET, mmio + HOST_CTL);
812 			readl(mmio + HOST_CTL); /* flush */
813 		}
814 
815 		/*
816 		 * to perform host reset, OS should set HOST_RESET
817 		 * and poll until this bit is read to be "0".
818 		 * reset must complete within 1 second, or
819 		 * the hardware should be considered fried.
820 		 */
821 		tmp = ata_wait_register(NULL, mmio + HOST_CTL, HOST_RESET,
822 					HOST_RESET, 10, 1000);
823 
824 		if (tmp & HOST_RESET) {
825 			dev_printk(KERN_ERR, host->dev,
826 				   "controller reset failed (0x%x)\n", tmp);
827 			return -EIO;
828 		}
829 
830 		/* turn on AHCI mode */
831 		ahci_enable_ahci(mmio);
832 
833 		/* Some registers might be cleared on reset.  Restore
834 		 * initial values.
835 		 */
836 		ahci_restore_initial_config(host);
837 	} else
838 		dev_printk(KERN_INFO, host->dev,
839 			   "skipping global host reset\n");
840 
841 	return 0;
842 }
843 EXPORT_SYMBOL_GPL(ahci_reset_controller);
844 
845 static void ahci_sw_activity(struct ata_link *link)
846 {
847 	struct ata_port *ap = link->ap;
848 	struct ahci_port_priv *pp = ap->private_data;
849 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
850 
851 	if (!(link->flags & ATA_LFLAG_SW_ACTIVITY))
852 		return;
853 
854 	emp->activity++;
855 	if (!timer_pending(&emp->timer))
856 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(10));
857 }
858 
859 static void ahci_sw_activity_blink(unsigned long arg)
860 {
861 	struct ata_link *link = (struct ata_link *)arg;
862 	struct ata_port *ap = link->ap;
863 	struct ahci_port_priv *pp = ap->private_data;
864 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
865 	unsigned long led_message = emp->led_state;
866 	u32 activity_led_state;
867 	unsigned long flags;
868 
869 	led_message &= EM_MSG_LED_VALUE;
870 	led_message |= ap->port_no | (link->pmp << 8);
871 
872 	/* check to see if we've had activity.  If so,
873 	 * toggle state of LED and reset timer.  If not,
874 	 * turn LED to desired idle state.
875 	 */
876 	spin_lock_irqsave(ap->lock, flags);
877 	if (emp->saved_activity != emp->activity) {
878 		emp->saved_activity = emp->activity;
879 		/* get the current LED state */
880 		activity_led_state = led_message & EM_MSG_LED_VALUE_ON;
881 
882 		if (activity_led_state)
883 			activity_led_state = 0;
884 		else
885 			activity_led_state = 1;
886 
887 		/* clear old state */
888 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
889 
890 		/* toggle state */
891 		led_message |= (activity_led_state << 16);
892 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(100));
893 	} else {
894 		/* switch to idle */
895 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
896 		if (emp->blink_policy == BLINK_OFF)
897 			led_message |= (1 << 16);
898 	}
899 	spin_unlock_irqrestore(ap->lock, flags);
900 	ahci_transmit_led_message(ap, led_message, 4);
901 }
902 
903 static void ahci_init_sw_activity(struct ata_link *link)
904 {
905 	struct ata_port *ap = link->ap;
906 	struct ahci_port_priv *pp = ap->private_data;
907 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
908 
909 	/* init activity stats, setup timer */
910 	emp->saved_activity = emp->activity = 0;
911 	setup_timer(&emp->timer, ahci_sw_activity_blink, (unsigned long)link);
912 
913 	/* check our blink policy and set flag for link if it's enabled */
914 	if (emp->blink_policy)
915 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
916 }
917 
918 int ahci_reset_em(struct ata_host *host)
919 {
920 	struct ahci_host_priv *hpriv = host->private_data;
921 	void __iomem *mmio = hpriv->mmio;
922 	u32 em_ctl;
923 
924 	em_ctl = readl(mmio + HOST_EM_CTL);
925 	if ((em_ctl & EM_CTL_TM) || (em_ctl & EM_CTL_RST))
926 		return -EINVAL;
927 
928 	writel(em_ctl | EM_CTL_RST, mmio + HOST_EM_CTL);
929 	return 0;
930 }
931 EXPORT_SYMBOL_GPL(ahci_reset_em);
932 
933 static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
934 					ssize_t size)
935 {
936 	struct ahci_host_priv *hpriv = ap->host->private_data;
937 	struct ahci_port_priv *pp = ap->private_data;
938 	void __iomem *mmio = hpriv->mmio;
939 	u32 em_ctl;
940 	u32 message[] = {0, 0};
941 	unsigned long flags;
942 	int pmp;
943 	struct ahci_em_priv *emp;
944 
945 	/* get the slot number from the message */
946 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
947 	if (pmp < EM_MAX_SLOTS)
948 		emp = &pp->em_priv[pmp];
949 	else
950 		return -EINVAL;
951 
952 	spin_lock_irqsave(ap->lock, flags);
953 
954 	/*
955 	 * if we are still busy transmitting a previous message,
956 	 * do not allow
957 	 */
958 	em_ctl = readl(mmio + HOST_EM_CTL);
959 	if (em_ctl & EM_CTL_TM) {
960 		spin_unlock_irqrestore(ap->lock, flags);
961 		return -EBUSY;
962 	}
963 
964 	if (hpriv->em_msg_type & EM_MSG_TYPE_LED) {
965 		/*
966 		 * create message header - this is all zero except for
967 		 * the message size, which is 4 bytes.
968 		 */
969 		message[0] |= (4 << 8);
970 
971 		/* ignore 0:4 of byte zero, fill in port info yourself */
972 		message[1] = ((state & ~EM_MSG_LED_HBA_PORT) | ap->port_no);
973 
974 		/* write message to EM_LOC */
975 		writel(message[0], mmio + hpriv->em_loc);
976 		writel(message[1], mmio + hpriv->em_loc+4);
977 
978 		/*
979 		 * tell hardware to transmit the message
980 		 */
981 		writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
982 	}
983 
984 	/* save off new led state for port/slot */
985 	emp->led_state = state;
986 
987 	spin_unlock_irqrestore(ap->lock, flags);
988 	return size;
989 }
990 
991 static ssize_t ahci_led_show(struct ata_port *ap, char *buf)
992 {
993 	struct ahci_port_priv *pp = ap->private_data;
994 	struct ata_link *link;
995 	struct ahci_em_priv *emp;
996 	int rc = 0;
997 
998 	ata_for_each_link(link, ap, EDGE) {
999 		emp = &pp->em_priv[link->pmp];
1000 		rc += sprintf(buf, "%lx\n", emp->led_state);
1001 	}
1002 	return rc;
1003 }
1004 
1005 static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
1006 				size_t size)
1007 {
1008 	int state;
1009 	int pmp;
1010 	struct ahci_port_priv *pp = ap->private_data;
1011 	struct ahci_em_priv *emp;
1012 
1013 	state = simple_strtoul(buf, NULL, 0);
1014 
1015 	/* get the slot number from the message */
1016 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
1017 	if (pmp < EM_MAX_SLOTS)
1018 		emp = &pp->em_priv[pmp];
1019 	else
1020 		return -EINVAL;
1021 
1022 	/* mask off the activity bits if we are in sw_activity
1023 	 * mode, user should turn off sw_activity before setting
1024 	 * activity led through em_message
1025 	 */
1026 	if (emp->blink_policy)
1027 		state &= ~EM_MSG_LED_VALUE_ACTIVITY;
1028 
1029 	return ahci_transmit_led_message(ap, state, size);
1030 }
1031 
1032 static ssize_t ahci_activity_store(struct ata_device *dev, enum sw_activity val)
1033 {
1034 	struct ata_link *link = dev->link;
1035 	struct ata_port *ap = link->ap;
1036 	struct ahci_port_priv *pp = ap->private_data;
1037 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1038 	u32 port_led_state = emp->led_state;
1039 
1040 	/* save the desired Activity LED behavior */
1041 	if (val == OFF) {
1042 		/* clear LFLAG */
1043 		link->flags &= ~(ATA_LFLAG_SW_ACTIVITY);
1044 
1045 		/* set the LED to OFF */
1046 		port_led_state &= EM_MSG_LED_VALUE_OFF;
1047 		port_led_state |= (ap->port_no | (link->pmp << 8));
1048 		ahci_transmit_led_message(ap, port_led_state, 4);
1049 	} else {
1050 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
1051 		if (val == BLINK_OFF) {
1052 			/* set LED to ON for idle */
1053 			port_led_state &= EM_MSG_LED_VALUE_OFF;
1054 			port_led_state |= (ap->port_no | (link->pmp << 8));
1055 			port_led_state |= EM_MSG_LED_VALUE_ON; /* check this */
1056 			ahci_transmit_led_message(ap, port_led_state, 4);
1057 		}
1058 	}
1059 	emp->blink_policy = val;
1060 	return 0;
1061 }
1062 
1063 static ssize_t ahci_activity_show(struct ata_device *dev, char *buf)
1064 {
1065 	struct ata_link *link = dev->link;
1066 	struct ata_port *ap = link->ap;
1067 	struct ahci_port_priv *pp = ap->private_data;
1068 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1069 
1070 	/* display the saved value of activity behavior for this
1071 	 * disk.
1072 	 */
1073 	return sprintf(buf, "%d\n", emp->blink_policy);
1074 }
1075 
1076 static void ahci_port_init(struct device *dev, struct ata_port *ap,
1077 			   int port_no, void __iomem *mmio,
1078 			   void __iomem *port_mmio)
1079 {
1080 	const char *emsg = NULL;
1081 	int rc;
1082 	u32 tmp;
1083 
1084 	/* make sure port is not active */
1085 	rc = ahci_deinit_port(ap, &emsg);
1086 	if (rc)
1087 		dev_warn(dev, "%s (%d)\n", emsg, rc);
1088 
1089 	/* clear SError */
1090 	tmp = readl(port_mmio + PORT_SCR_ERR);
1091 	VPRINTK("PORT_SCR_ERR 0x%x\n", tmp);
1092 	writel(tmp, port_mmio + PORT_SCR_ERR);
1093 
1094 	/* clear port IRQ */
1095 	tmp = readl(port_mmio + PORT_IRQ_STAT);
1096 	VPRINTK("PORT_IRQ_STAT 0x%x\n", tmp);
1097 	if (tmp)
1098 		writel(tmp, port_mmio + PORT_IRQ_STAT);
1099 
1100 	writel(1 << port_no, mmio + HOST_IRQ_STAT);
1101 }
1102 
1103 void ahci_init_controller(struct ata_host *host)
1104 {
1105 	struct ahci_host_priv *hpriv = host->private_data;
1106 	void __iomem *mmio = hpriv->mmio;
1107 	int i;
1108 	void __iomem *port_mmio;
1109 	u32 tmp;
1110 
1111 	for (i = 0; i < host->n_ports; i++) {
1112 		struct ata_port *ap = host->ports[i];
1113 
1114 		port_mmio = ahci_port_base(ap);
1115 		if (ata_port_is_dummy(ap))
1116 			continue;
1117 
1118 		ahci_port_init(host->dev, ap, i, mmio, port_mmio);
1119 	}
1120 
1121 	tmp = readl(mmio + HOST_CTL);
1122 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1123 	writel(tmp | HOST_IRQ_EN, mmio + HOST_CTL);
1124 	tmp = readl(mmio + HOST_CTL);
1125 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1126 }
1127 EXPORT_SYMBOL_GPL(ahci_init_controller);
1128 
1129 static void ahci_dev_config(struct ata_device *dev)
1130 {
1131 	struct ahci_host_priv *hpriv = dev->link->ap->host->private_data;
1132 
1133 	if (hpriv->flags & AHCI_HFLAG_SECT255) {
1134 		dev->max_sectors = 255;
1135 		ata_dev_printk(dev, KERN_INFO,
1136 			       "SB600 AHCI: limiting to 255 sectors per cmd\n");
1137 	}
1138 }
1139 
1140 static unsigned int ahci_dev_classify(struct ata_port *ap)
1141 {
1142 	void __iomem *port_mmio = ahci_port_base(ap);
1143 	struct ata_taskfile tf;
1144 	u32 tmp;
1145 
1146 	tmp = readl(port_mmio + PORT_SIG);
1147 	tf.lbah		= (tmp >> 24)	& 0xff;
1148 	tf.lbam		= (tmp >> 16)	& 0xff;
1149 	tf.lbal		= (tmp >> 8)	& 0xff;
1150 	tf.nsect	= (tmp)		& 0xff;
1151 
1152 	return ata_dev_classify(&tf);
1153 }
1154 
1155 void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
1156 			u32 opts)
1157 {
1158 	dma_addr_t cmd_tbl_dma;
1159 
1160 	cmd_tbl_dma = pp->cmd_tbl_dma + tag * AHCI_CMD_TBL_SZ;
1161 
1162 	pp->cmd_slot[tag].opts = cpu_to_le32(opts);
1163 	pp->cmd_slot[tag].status = 0;
1164 	pp->cmd_slot[tag].tbl_addr = cpu_to_le32(cmd_tbl_dma & 0xffffffff);
1165 	pp->cmd_slot[tag].tbl_addr_hi = cpu_to_le32((cmd_tbl_dma >> 16) >> 16);
1166 }
1167 EXPORT_SYMBOL_GPL(ahci_fill_cmd_slot);
1168 
1169 int ahci_kick_engine(struct ata_port *ap)
1170 {
1171 	void __iomem *port_mmio = ahci_port_base(ap);
1172 	struct ahci_host_priv *hpriv = ap->host->private_data;
1173 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1174 	u32 tmp;
1175 	int busy, rc;
1176 
1177 	/* stop engine */
1178 	rc = ahci_stop_engine(ap);
1179 	if (rc)
1180 		goto out_restart;
1181 
1182 	/* need to do CLO?
1183 	 * always do CLO if PMP is attached (AHCI-1.3 9.2)
1184 	 */
1185 	busy = status & (ATA_BUSY | ATA_DRQ);
1186 	if (!busy && !sata_pmp_attached(ap)) {
1187 		rc = 0;
1188 		goto out_restart;
1189 	}
1190 
1191 	if (!(hpriv->cap & HOST_CAP_CLO)) {
1192 		rc = -EOPNOTSUPP;
1193 		goto out_restart;
1194 	}
1195 
1196 	/* perform CLO */
1197 	tmp = readl(port_mmio + PORT_CMD);
1198 	tmp |= PORT_CMD_CLO;
1199 	writel(tmp, port_mmio + PORT_CMD);
1200 
1201 	rc = 0;
1202 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
1203 				PORT_CMD_CLO, PORT_CMD_CLO, 1, 500);
1204 	if (tmp & PORT_CMD_CLO)
1205 		rc = -EIO;
1206 
1207 	/* restart engine */
1208  out_restart:
1209 	ahci_start_engine(ap);
1210 	return rc;
1211 }
1212 EXPORT_SYMBOL_GPL(ahci_kick_engine);
1213 
1214 static int ahci_exec_polled_cmd(struct ata_port *ap, int pmp,
1215 				struct ata_taskfile *tf, int is_cmd, u16 flags,
1216 				unsigned long timeout_msec)
1217 {
1218 	const u32 cmd_fis_len = 5; /* five dwords */
1219 	struct ahci_port_priv *pp = ap->private_data;
1220 	void __iomem *port_mmio = ahci_port_base(ap);
1221 	u8 *fis = pp->cmd_tbl;
1222 	u32 tmp;
1223 
1224 	/* prep the command */
1225 	ata_tf_to_fis(tf, pmp, is_cmd, fis);
1226 	ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12));
1227 
1228 	/* issue & wait */
1229 	writel(1, port_mmio + PORT_CMD_ISSUE);
1230 
1231 	if (timeout_msec) {
1232 		tmp = ata_wait_register(ap, port_mmio + PORT_CMD_ISSUE,
1233 					0x1, 0x1, 1, timeout_msec);
1234 		if (tmp & 0x1) {
1235 			ahci_kick_engine(ap);
1236 			return -EBUSY;
1237 		}
1238 	} else
1239 		readl(port_mmio + PORT_CMD_ISSUE);	/* flush */
1240 
1241 	return 0;
1242 }
1243 
1244 int ahci_do_softreset(struct ata_link *link, unsigned int *class,
1245 		      int pmp, unsigned long deadline,
1246 		      int (*check_ready)(struct ata_link *link))
1247 {
1248 	struct ata_port *ap = link->ap;
1249 	struct ahci_host_priv *hpriv = ap->host->private_data;
1250 	const char *reason = NULL;
1251 	unsigned long now, msecs;
1252 	struct ata_taskfile tf;
1253 	int rc;
1254 
1255 	DPRINTK("ENTER\n");
1256 
1257 	/* prepare for SRST (AHCI-1.1 10.4.1) */
1258 	rc = ahci_kick_engine(ap);
1259 	if (rc && rc != -EOPNOTSUPP)
1260 		ata_link_printk(link, KERN_WARNING,
1261 				"failed to reset engine (errno=%d)\n", rc);
1262 
1263 	ata_tf_init(link->device, &tf);
1264 
1265 	/* issue the first D2H Register FIS */
1266 	msecs = 0;
1267 	now = jiffies;
1268 	if (time_after(deadline, now))
1269 		msecs = jiffies_to_msecs(deadline - now);
1270 
1271 	tf.ctl |= ATA_SRST;
1272 	if (ahci_exec_polled_cmd(ap, pmp, &tf, 0,
1273 				 AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY, msecs)) {
1274 		rc = -EIO;
1275 		reason = "1st FIS failed";
1276 		goto fail;
1277 	}
1278 
1279 	/* spec says at least 5us, but be generous and sleep for 1ms */
1280 	ata_msleep(ap, 1);
1281 
1282 	/* issue the second D2H Register FIS */
1283 	tf.ctl &= ~ATA_SRST;
1284 	ahci_exec_polled_cmd(ap, pmp, &tf, 0, 0, 0);
1285 
1286 	/* wait for link to become ready */
1287 	rc = ata_wait_after_reset(link, deadline, check_ready);
1288 	if (rc == -EBUSY && hpriv->flags & AHCI_HFLAG_SRST_TOUT_IS_OFFLINE) {
1289 		/*
1290 		 * Workaround for cases where link online status can't
1291 		 * be trusted.  Treat device readiness timeout as link
1292 		 * offline.
1293 		 */
1294 		ata_link_printk(link, KERN_INFO,
1295 				"device not ready, treating as offline\n");
1296 		*class = ATA_DEV_NONE;
1297 	} else if (rc) {
1298 		/* link occupied, -ENODEV too is an error */
1299 		reason = "device not ready";
1300 		goto fail;
1301 	} else
1302 		*class = ahci_dev_classify(ap);
1303 
1304 	DPRINTK("EXIT, class=%u\n", *class);
1305 	return 0;
1306 
1307  fail:
1308 	ata_link_printk(link, KERN_ERR, "softreset failed (%s)\n", reason);
1309 	return rc;
1310 }
1311 
1312 int ahci_check_ready(struct ata_link *link)
1313 {
1314 	void __iomem *port_mmio = ahci_port_base(link->ap);
1315 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1316 
1317 	return ata_check_ready(status);
1318 }
1319 EXPORT_SYMBOL_GPL(ahci_check_ready);
1320 
1321 static int ahci_softreset(struct ata_link *link, unsigned int *class,
1322 			  unsigned long deadline)
1323 {
1324 	int pmp = sata_srst_pmp(link);
1325 
1326 	DPRINTK("ENTER\n");
1327 
1328 	return ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
1329 }
1330 EXPORT_SYMBOL_GPL(ahci_do_softreset);
1331 
1332 static int ahci_hardreset(struct ata_link *link, unsigned int *class,
1333 			  unsigned long deadline)
1334 {
1335 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
1336 	struct ata_port *ap = link->ap;
1337 	struct ahci_port_priv *pp = ap->private_data;
1338 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
1339 	struct ata_taskfile tf;
1340 	bool online;
1341 	int rc;
1342 
1343 	DPRINTK("ENTER\n");
1344 
1345 	ahci_stop_engine(ap);
1346 
1347 	/* clear D2H reception area to properly wait for D2H FIS */
1348 	ata_tf_init(link->device, &tf);
1349 	tf.command = 0x80;
1350 	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
1351 
1352 	rc = sata_link_hardreset(link, timing, deadline, &online,
1353 				 ahci_check_ready);
1354 
1355 	ahci_start_engine(ap);
1356 
1357 	if (online)
1358 		*class = ahci_dev_classify(ap);
1359 
1360 	DPRINTK("EXIT, rc=%d, class=%u\n", rc, *class);
1361 	return rc;
1362 }
1363 
1364 static void ahci_postreset(struct ata_link *link, unsigned int *class)
1365 {
1366 	struct ata_port *ap = link->ap;
1367 	void __iomem *port_mmio = ahci_port_base(ap);
1368 	u32 new_tmp, tmp;
1369 
1370 	ata_std_postreset(link, class);
1371 
1372 	/* Make sure port's ATAPI bit is set appropriately */
1373 	new_tmp = tmp = readl(port_mmio + PORT_CMD);
1374 	if (*class == ATA_DEV_ATAPI)
1375 		new_tmp |= PORT_CMD_ATAPI;
1376 	else
1377 		new_tmp &= ~PORT_CMD_ATAPI;
1378 	if (new_tmp != tmp) {
1379 		writel(new_tmp, port_mmio + PORT_CMD);
1380 		readl(port_mmio + PORT_CMD); /* flush */
1381 	}
1382 }
1383 
1384 static unsigned int ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl)
1385 {
1386 	struct scatterlist *sg;
1387 	struct ahci_sg *ahci_sg = cmd_tbl + AHCI_CMD_TBL_HDR_SZ;
1388 	unsigned int si;
1389 
1390 	VPRINTK("ENTER\n");
1391 
1392 	/*
1393 	 * Next, the S/G list.
1394 	 */
1395 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
1396 		dma_addr_t addr = sg_dma_address(sg);
1397 		u32 sg_len = sg_dma_len(sg);
1398 
1399 		ahci_sg[si].addr = cpu_to_le32(addr & 0xffffffff);
1400 		ahci_sg[si].addr_hi = cpu_to_le32((addr >> 16) >> 16);
1401 		ahci_sg[si].flags_size = cpu_to_le32(sg_len - 1);
1402 	}
1403 
1404 	return si;
1405 }
1406 
1407 static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc)
1408 {
1409 	struct ata_port *ap = qc->ap;
1410 	struct ahci_port_priv *pp = ap->private_data;
1411 
1412 	if (!sata_pmp_attached(ap) || pp->fbs_enabled)
1413 		return ata_std_qc_defer(qc);
1414 	else
1415 		return sata_pmp_qc_defer_cmd_switch(qc);
1416 }
1417 
1418 static void ahci_qc_prep(struct ata_queued_cmd *qc)
1419 {
1420 	struct ata_port *ap = qc->ap;
1421 	struct ahci_port_priv *pp = ap->private_data;
1422 	int is_atapi = ata_is_atapi(qc->tf.protocol);
1423 	void *cmd_tbl;
1424 	u32 opts;
1425 	const u32 cmd_fis_len = 5; /* five dwords */
1426 	unsigned int n_elem;
1427 
1428 	/*
1429 	 * Fill in command table information.  First, the header,
1430 	 * a SATA Register - Host to Device command FIS.
1431 	 */
1432 	cmd_tbl = pp->cmd_tbl + qc->tag * AHCI_CMD_TBL_SZ;
1433 
1434 	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, cmd_tbl);
1435 	if (is_atapi) {
1436 		memset(cmd_tbl + AHCI_CMD_TBL_CDB, 0, 32);
1437 		memcpy(cmd_tbl + AHCI_CMD_TBL_CDB, qc->cdb, qc->dev->cdb_len);
1438 	}
1439 
1440 	n_elem = 0;
1441 	if (qc->flags & ATA_QCFLAG_DMAMAP)
1442 		n_elem = ahci_fill_sg(qc, cmd_tbl);
1443 
1444 	/*
1445 	 * Fill in command slot information.
1446 	 */
1447 	opts = cmd_fis_len | n_elem << 16 | (qc->dev->link->pmp << 12);
1448 	if (qc->tf.flags & ATA_TFLAG_WRITE)
1449 		opts |= AHCI_CMD_WRITE;
1450 	if (is_atapi)
1451 		opts |= AHCI_CMD_ATAPI | AHCI_CMD_PREFETCH;
1452 
1453 	ahci_fill_cmd_slot(pp, qc->tag, opts);
1454 }
1455 
1456 static void ahci_fbs_dec_intr(struct ata_port *ap)
1457 {
1458 	struct ahci_port_priv *pp = ap->private_data;
1459 	void __iomem *port_mmio = ahci_port_base(ap);
1460 	u32 fbs = readl(port_mmio + PORT_FBS);
1461 	int retries = 3;
1462 
1463 	DPRINTK("ENTER\n");
1464 	BUG_ON(!pp->fbs_enabled);
1465 
1466 	/* time to wait for DEC is not specified by AHCI spec,
1467 	 * add a retry loop for safety.
1468 	 */
1469 	writel(fbs | PORT_FBS_DEC, port_mmio + PORT_FBS);
1470 	fbs = readl(port_mmio + PORT_FBS);
1471 	while ((fbs & PORT_FBS_DEC) && retries--) {
1472 		udelay(1);
1473 		fbs = readl(port_mmio + PORT_FBS);
1474 	}
1475 
1476 	if (fbs & PORT_FBS_DEC)
1477 		dev_printk(KERN_ERR, ap->host->dev,
1478 			   "failed to clear device error\n");
1479 }
1480 
1481 static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
1482 {
1483 	struct ahci_host_priv *hpriv = ap->host->private_data;
1484 	struct ahci_port_priv *pp = ap->private_data;
1485 	struct ata_eh_info *host_ehi = &ap->link.eh_info;
1486 	struct ata_link *link = NULL;
1487 	struct ata_queued_cmd *active_qc;
1488 	struct ata_eh_info *active_ehi;
1489 	bool fbs_need_dec = false;
1490 	u32 serror;
1491 
1492 	/* determine active link with error */
1493 	if (pp->fbs_enabled) {
1494 		void __iomem *port_mmio = ahci_port_base(ap);
1495 		u32 fbs = readl(port_mmio + PORT_FBS);
1496 		int pmp = fbs >> PORT_FBS_DWE_OFFSET;
1497 
1498 		if ((fbs & PORT_FBS_SDE) && (pmp < ap->nr_pmp_links) &&
1499 		    ata_link_online(&ap->pmp_link[pmp])) {
1500 			link = &ap->pmp_link[pmp];
1501 			fbs_need_dec = true;
1502 		}
1503 
1504 	} else
1505 		ata_for_each_link(link, ap, EDGE)
1506 			if (ata_link_active(link))
1507 				break;
1508 
1509 	if (!link)
1510 		link = &ap->link;
1511 
1512 	active_qc = ata_qc_from_tag(ap, link->active_tag);
1513 	active_ehi = &link->eh_info;
1514 
1515 	/* record irq stat */
1516 	ata_ehi_clear_desc(host_ehi);
1517 	ata_ehi_push_desc(host_ehi, "irq_stat 0x%08x", irq_stat);
1518 
1519 	/* AHCI needs SError cleared; otherwise, it might lock up */
1520 	ahci_scr_read(&ap->link, SCR_ERROR, &serror);
1521 	ahci_scr_write(&ap->link, SCR_ERROR, serror);
1522 	host_ehi->serror |= serror;
1523 
1524 	/* some controllers set IRQ_IF_ERR on device errors, ignore it */
1525 	if (hpriv->flags & AHCI_HFLAG_IGN_IRQ_IF_ERR)
1526 		irq_stat &= ~PORT_IRQ_IF_ERR;
1527 
1528 	if (irq_stat & PORT_IRQ_TF_ERR) {
1529 		/* If qc is active, charge it; otherwise, the active
1530 		 * link.  There's no active qc on NCQ errors.  It will
1531 		 * be determined by EH by reading log page 10h.
1532 		 */
1533 		if (active_qc)
1534 			active_qc->err_mask |= AC_ERR_DEV;
1535 		else
1536 			active_ehi->err_mask |= AC_ERR_DEV;
1537 
1538 		if (hpriv->flags & AHCI_HFLAG_IGN_SERR_INTERNAL)
1539 			host_ehi->serror &= ~SERR_INTERNAL;
1540 	}
1541 
1542 	if (irq_stat & PORT_IRQ_UNK_FIS) {
1543 		u32 *unk = (u32 *)(pp->rx_fis + RX_FIS_UNK);
1544 
1545 		active_ehi->err_mask |= AC_ERR_HSM;
1546 		active_ehi->action |= ATA_EH_RESET;
1547 		ata_ehi_push_desc(active_ehi,
1548 				  "unknown FIS %08x %08x %08x %08x" ,
1549 				  unk[0], unk[1], unk[2], unk[3]);
1550 	}
1551 
1552 	if (sata_pmp_attached(ap) && (irq_stat & PORT_IRQ_BAD_PMP)) {
1553 		active_ehi->err_mask |= AC_ERR_HSM;
1554 		active_ehi->action |= ATA_EH_RESET;
1555 		ata_ehi_push_desc(active_ehi, "incorrect PMP");
1556 	}
1557 
1558 	if (irq_stat & (PORT_IRQ_HBUS_ERR | PORT_IRQ_HBUS_DATA_ERR)) {
1559 		host_ehi->err_mask |= AC_ERR_HOST_BUS;
1560 		host_ehi->action |= ATA_EH_RESET;
1561 		ata_ehi_push_desc(host_ehi, "host bus error");
1562 	}
1563 
1564 	if (irq_stat & PORT_IRQ_IF_ERR) {
1565 		if (fbs_need_dec)
1566 			active_ehi->err_mask |= AC_ERR_DEV;
1567 		else {
1568 			host_ehi->err_mask |= AC_ERR_ATA_BUS;
1569 			host_ehi->action |= ATA_EH_RESET;
1570 		}
1571 
1572 		ata_ehi_push_desc(host_ehi, "interface fatal error");
1573 	}
1574 
1575 	if (irq_stat & (PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)) {
1576 		ata_ehi_hotplugged(host_ehi);
1577 		ata_ehi_push_desc(host_ehi, "%s",
1578 			irq_stat & PORT_IRQ_CONNECT ?
1579 			"connection status changed" : "PHY RDY changed");
1580 	}
1581 
1582 	/* okay, let's hand over to EH */
1583 
1584 	if (irq_stat & PORT_IRQ_FREEZE)
1585 		ata_port_freeze(ap);
1586 	else if (fbs_need_dec) {
1587 		ata_link_abort(link);
1588 		ahci_fbs_dec_intr(ap);
1589 	} else
1590 		ata_port_abort(ap);
1591 }
1592 
1593 static void ahci_port_intr(struct ata_port *ap)
1594 {
1595 	void __iomem *port_mmio = ahci_port_base(ap);
1596 	struct ata_eh_info *ehi = &ap->link.eh_info;
1597 	struct ahci_port_priv *pp = ap->private_data;
1598 	struct ahci_host_priv *hpriv = ap->host->private_data;
1599 	int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
1600 	u32 status, qc_active = 0;
1601 	int rc;
1602 
1603 	status = readl(port_mmio + PORT_IRQ_STAT);
1604 	writel(status, port_mmio + PORT_IRQ_STAT);
1605 
1606 	/* ignore BAD_PMP while resetting */
1607 	if (unlikely(resetting))
1608 		status &= ~PORT_IRQ_BAD_PMP;
1609 
1610 	/* if LPM is enabled, PHYRDY doesn't mean anything */
1611 	if (ap->link.lpm_policy > ATA_LPM_MAX_POWER) {
1612 		status &= ~PORT_IRQ_PHYRDY;
1613 		ahci_scr_write(&ap->link, SCR_ERROR, SERR_PHYRDY_CHG);
1614 	}
1615 
1616 	if (unlikely(status & PORT_IRQ_ERROR)) {
1617 		ahci_error_intr(ap, status);
1618 		return;
1619 	}
1620 
1621 	if (status & PORT_IRQ_SDB_FIS) {
1622 		/* If SNotification is available, leave notification
1623 		 * handling to sata_async_notification().  If not,
1624 		 * emulate it by snooping SDB FIS RX area.
1625 		 *
1626 		 * Snooping FIS RX area is probably cheaper than
1627 		 * poking SNotification but some constrollers which
1628 		 * implement SNotification, ICH9 for example, don't
1629 		 * store AN SDB FIS into receive area.
1630 		 */
1631 		if (hpriv->cap & HOST_CAP_SNTF)
1632 			sata_async_notification(ap);
1633 		else {
1634 			/* If the 'N' bit in word 0 of the FIS is set,
1635 			 * we just received asynchronous notification.
1636 			 * Tell libata about it.
1637 			 *
1638 			 * Lack of SNotification should not appear in
1639 			 * ahci 1.2, so the workaround is unnecessary
1640 			 * when FBS is enabled.
1641 			 */
1642 			if (pp->fbs_enabled)
1643 				WARN_ON_ONCE(1);
1644 			else {
1645 				const __le32 *f = pp->rx_fis + RX_FIS_SDB;
1646 				u32 f0 = le32_to_cpu(f[0]);
1647 				if (f0 & (1 << 15))
1648 					sata_async_notification(ap);
1649 			}
1650 		}
1651 	}
1652 
1653 	/* pp->active_link is not reliable once FBS is enabled, both
1654 	 * PORT_SCR_ACT and PORT_CMD_ISSUE should be checked because
1655 	 * NCQ and non-NCQ commands may be in flight at the same time.
1656 	 */
1657 	if (pp->fbs_enabled) {
1658 		if (ap->qc_active) {
1659 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1660 			qc_active |= readl(port_mmio + PORT_CMD_ISSUE);
1661 		}
1662 	} else {
1663 		/* pp->active_link is valid iff any command is in flight */
1664 		if (ap->qc_active && pp->active_link->sactive)
1665 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1666 		else
1667 			qc_active = readl(port_mmio + PORT_CMD_ISSUE);
1668 	}
1669 
1670 
1671 	rc = ata_qc_complete_multiple(ap, qc_active);
1672 
1673 	/* while resetting, invalid completions are expected */
1674 	if (unlikely(rc < 0 && !resetting)) {
1675 		ehi->err_mask |= AC_ERR_HSM;
1676 		ehi->action |= ATA_EH_RESET;
1677 		ata_port_freeze(ap);
1678 	}
1679 }
1680 
1681 irqreturn_t ahci_interrupt(int irq, void *dev_instance)
1682 {
1683 	struct ata_host *host = dev_instance;
1684 	struct ahci_host_priv *hpriv;
1685 	unsigned int i, handled = 0;
1686 	void __iomem *mmio;
1687 	u32 irq_stat, irq_masked;
1688 
1689 	VPRINTK("ENTER\n");
1690 
1691 	hpriv = host->private_data;
1692 	mmio = hpriv->mmio;
1693 
1694 	/* sigh.  0xffffffff is a valid return from h/w */
1695 	irq_stat = readl(mmio + HOST_IRQ_STAT);
1696 	if (!irq_stat)
1697 		return IRQ_NONE;
1698 
1699 	irq_masked = irq_stat & hpriv->port_map;
1700 
1701 	spin_lock(&host->lock);
1702 
1703 	for (i = 0; i < host->n_ports; i++) {
1704 		struct ata_port *ap;
1705 
1706 		if (!(irq_masked & (1 << i)))
1707 			continue;
1708 
1709 		ap = host->ports[i];
1710 		if (ap) {
1711 			ahci_port_intr(ap);
1712 			VPRINTK("port %u\n", i);
1713 		} else {
1714 			VPRINTK("port %u (no irq)\n", i);
1715 			if (ata_ratelimit())
1716 				dev_printk(KERN_WARNING, host->dev,
1717 					"interrupt on disabled port %u\n", i);
1718 		}
1719 
1720 		handled = 1;
1721 	}
1722 
1723 	/* HOST_IRQ_STAT behaves as level triggered latch meaning that
1724 	 * it should be cleared after all the port events are cleared;
1725 	 * otherwise, it will raise a spurious interrupt after each
1726 	 * valid one.  Please read section 10.6.2 of ahci 1.1 for more
1727 	 * information.
1728 	 *
1729 	 * Also, use the unmasked value to clear interrupt as spurious
1730 	 * pending event on a dummy port might cause screaming IRQ.
1731 	 */
1732 	writel(irq_stat, mmio + HOST_IRQ_STAT);
1733 
1734 	spin_unlock(&host->lock);
1735 
1736 	VPRINTK("EXIT\n");
1737 
1738 	return IRQ_RETVAL(handled);
1739 }
1740 EXPORT_SYMBOL_GPL(ahci_interrupt);
1741 
1742 static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
1743 {
1744 	struct ata_port *ap = qc->ap;
1745 	void __iomem *port_mmio = ahci_port_base(ap);
1746 	struct ahci_port_priv *pp = ap->private_data;
1747 
1748 	/* Keep track of the currently active link.  It will be used
1749 	 * in completion path to determine whether NCQ phase is in
1750 	 * progress.
1751 	 */
1752 	pp->active_link = qc->dev->link;
1753 
1754 	if (qc->tf.protocol == ATA_PROT_NCQ)
1755 		writel(1 << qc->tag, port_mmio + PORT_SCR_ACT);
1756 
1757 	if (pp->fbs_enabled && pp->fbs_last_dev != qc->dev->link->pmp) {
1758 		u32 fbs = readl(port_mmio + PORT_FBS);
1759 		fbs &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC);
1760 		fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
1761 		writel(fbs, port_mmio + PORT_FBS);
1762 		pp->fbs_last_dev = qc->dev->link->pmp;
1763 	}
1764 
1765 	writel(1 << qc->tag, port_mmio + PORT_CMD_ISSUE);
1766 
1767 	ahci_sw_activity(qc->dev->link);
1768 
1769 	return 0;
1770 }
1771 
1772 static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
1773 {
1774 	struct ahci_port_priv *pp = qc->ap->private_data;
1775 	u8 *rx_fis = pp->rx_fis;
1776 
1777 	if (pp->fbs_enabled)
1778 		rx_fis += qc->dev->link->pmp * AHCI_RX_FIS_SZ;
1779 
1780 	/*
1781 	 * After a successful execution of an ATA PIO data-in command,
1782 	 * the device doesn't send D2H Reg FIS to update the TF and
1783 	 * the host should take TF and E_Status from the preceding PIO
1784 	 * Setup FIS.
1785 	 */
1786 	if (qc->tf.protocol == ATA_PROT_PIO && qc->dma_dir == DMA_FROM_DEVICE &&
1787 	    !(qc->flags & ATA_QCFLAG_FAILED)) {
1788 		ata_tf_from_fis(rx_fis + RX_FIS_PIO_SETUP, &qc->result_tf);
1789 		qc->result_tf.command = (rx_fis + RX_FIS_PIO_SETUP)[15];
1790 	} else
1791 		ata_tf_from_fis(rx_fis + RX_FIS_D2H_REG, &qc->result_tf);
1792 
1793 	return true;
1794 }
1795 
1796 static void ahci_freeze(struct ata_port *ap)
1797 {
1798 	void __iomem *port_mmio = ahci_port_base(ap);
1799 
1800 	/* turn IRQ off */
1801 	writel(0, port_mmio + PORT_IRQ_MASK);
1802 }
1803 
1804 static void ahci_thaw(struct ata_port *ap)
1805 {
1806 	struct ahci_host_priv *hpriv = ap->host->private_data;
1807 	void __iomem *mmio = hpriv->mmio;
1808 	void __iomem *port_mmio = ahci_port_base(ap);
1809 	u32 tmp;
1810 	struct ahci_port_priv *pp = ap->private_data;
1811 
1812 	/* clear IRQ */
1813 	tmp = readl(port_mmio + PORT_IRQ_STAT);
1814 	writel(tmp, port_mmio + PORT_IRQ_STAT);
1815 	writel(1 << ap->port_no, mmio + HOST_IRQ_STAT);
1816 
1817 	/* turn IRQ back on */
1818 	writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
1819 }
1820 
1821 static void ahci_error_handler(struct ata_port *ap)
1822 {
1823 	if (!(ap->pflags & ATA_PFLAG_FROZEN)) {
1824 		/* restart engine */
1825 		ahci_stop_engine(ap);
1826 		ahci_start_engine(ap);
1827 	}
1828 
1829 	sata_pmp_error_handler(ap);
1830 
1831 	if (!ata_dev_enabled(ap->link.device))
1832 		ahci_stop_engine(ap);
1833 }
1834 
1835 static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
1836 {
1837 	struct ata_port *ap = qc->ap;
1838 
1839 	/* make DMA engine forget about the failed command */
1840 	if (qc->flags & ATA_QCFLAG_FAILED)
1841 		ahci_kick_engine(ap);
1842 }
1843 
1844 static void ahci_enable_fbs(struct ata_port *ap)
1845 {
1846 	struct ahci_port_priv *pp = ap->private_data;
1847 	void __iomem *port_mmio = ahci_port_base(ap);
1848 	u32 fbs;
1849 	int rc;
1850 
1851 	if (!pp->fbs_supported)
1852 		return;
1853 
1854 	fbs = readl(port_mmio + PORT_FBS);
1855 	if (fbs & PORT_FBS_EN) {
1856 		pp->fbs_enabled = true;
1857 		pp->fbs_last_dev = -1; /* initialization */
1858 		return;
1859 	}
1860 
1861 	rc = ahci_stop_engine(ap);
1862 	if (rc)
1863 		return;
1864 
1865 	writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
1866 	fbs = readl(port_mmio + PORT_FBS);
1867 	if (fbs & PORT_FBS_EN) {
1868 		dev_printk(KERN_INFO, ap->host->dev, "FBS is enabled.\n");
1869 		pp->fbs_enabled = true;
1870 		pp->fbs_last_dev = -1; /* initialization */
1871 	} else
1872 		dev_printk(KERN_ERR, ap->host->dev, "Failed to enable FBS\n");
1873 
1874 	ahci_start_engine(ap);
1875 }
1876 
1877 static void ahci_disable_fbs(struct ata_port *ap)
1878 {
1879 	struct ahci_port_priv *pp = ap->private_data;
1880 	void __iomem *port_mmio = ahci_port_base(ap);
1881 	u32 fbs;
1882 	int rc;
1883 
1884 	if (!pp->fbs_supported)
1885 		return;
1886 
1887 	fbs = readl(port_mmio + PORT_FBS);
1888 	if ((fbs & PORT_FBS_EN) == 0) {
1889 		pp->fbs_enabled = false;
1890 		return;
1891 	}
1892 
1893 	rc = ahci_stop_engine(ap);
1894 	if (rc)
1895 		return;
1896 
1897 	writel(fbs & ~PORT_FBS_EN, port_mmio + PORT_FBS);
1898 	fbs = readl(port_mmio + PORT_FBS);
1899 	if (fbs & PORT_FBS_EN)
1900 		dev_printk(KERN_ERR, ap->host->dev, "Failed to disable FBS\n");
1901 	else {
1902 		dev_printk(KERN_INFO, ap->host->dev, "FBS is disabled.\n");
1903 		pp->fbs_enabled = false;
1904 	}
1905 
1906 	ahci_start_engine(ap);
1907 }
1908 
1909 static void ahci_pmp_attach(struct ata_port *ap)
1910 {
1911 	void __iomem *port_mmio = ahci_port_base(ap);
1912 	struct ahci_port_priv *pp = ap->private_data;
1913 	u32 cmd;
1914 
1915 	cmd = readl(port_mmio + PORT_CMD);
1916 	cmd |= PORT_CMD_PMP;
1917 	writel(cmd, port_mmio + PORT_CMD);
1918 
1919 	ahci_enable_fbs(ap);
1920 
1921 	pp->intr_mask |= PORT_IRQ_BAD_PMP;
1922 
1923 	/*
1924 	 * We must not change the port interrupt mask register if the
1925 	 * port is marked frozen, the value in pp->intr_mask will be
1926 	 * restored later when the port is thawed.
1927 	 *
1928 	 * Note that during initialization, the port is marked as
1929 	 * frozen since the irq handler is not yet registered.
1930 	 */
1931 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
1932 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
1933 }
1934 
1935 static void ahci_pmp_detach(struct ata_port *ap)
1936 {
1937 	void __iomem *port_mmio = ahci_port_base(ap);
1938 	struct ahci_port_priv *pp = ap->private_data;
1939 	u32 cmd;
1940 
1941 	ahci_disable_fbs(ap);
1942 
1943 	cmd = readl(port_mmio + PORT_CMD);
1944 	cmd &= ~PORT_CMD_PMP;
1945 	writel(cmd, port_mmio + PORT_CMD);
1946 
1947 	pp->intr_mask &= ~PORT_IRQ_BAD_PMP;
1948 
1949 	/* see comment above in ahci_pmp_attach() */
1950 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
1951 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
1952 }
1953 
1954 int ahci_port_resume(struct ata_port *ap)
1955 {
1956 	ahci_power_up(ap);
1957 	ahci_start_port(ap);
1958 
1959 	if (sata_pmp_attached(ap))
1960 		ahci_pmp_attach(ap);
1961 	else
1962 		ahci_pmp_detach(ap);
1963 
1964 	return 0;
1965 }
1966 EXPORT_SYMBOL_GPL(ahci_port_resume);
1967 
1968 #ifdef CONFIG_PM
1969 static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg)
1970 {
1971 	const char *emsg = NULL;
1972 	int rc;
1973 
1974 	rc = ahci_deinit_port(ap, &emsg);
1975 	if (rc == 0)
1976 		ahci_power_down(ap);
1977 	else {
1978 		ata_port_printk(ap, KERN_ERR, "%s (%d)\n", emsg, rc);
1979 		ahci_start_port(ap);
1980 	}
1981 
1982 	return rc;
1983 }
1984 #endif
1985 
1986 static int ahci_port_start(struct ata_port *ap)
1987 {
1988 	struct ahci_host_priv *hpriv = ap->host->private_data;
1989 	struct device *dev = ap->host->dev;
1990 	struct ahci_port_priv *pp;
1991 	void *mem;
1992 	dma_addr_t mem_dma;
1993 	size_t dma_sz, rx_fis_sz;
1994 
1995 	pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
1996 	if (!pp)
1997 		return -ENOMEM;
1998 
1999 	/* check FBS capability */
2000 	if ((hpriv->cap & HOST_CAP_FBS) && sata_pmp_supported(ap)) {
2001 		void __iomem *port_mmio = ahci_port_base(ap);
2002 		u32 cmd = readl(port_mmio + PORT_CMD);
2003 		if (cmd & PORT_CMD_FBSCP)
2004 			pp->fbs_supported = true;
2005 		else if (hpriv->flags & AHCI_HFLAG_YES_FBS) {
2006 			dev_printk(KERN_INFO, dev,
2007 				   "port %d can do FBS, forcing FBSCP\n",
2008 				   ap->port_no);
2009 			pp->fbs_supported = true;
2010 		} else
2011 			dev_printk(KERN_WARNING, dev,
2012 				   "port %d is not capable of FBS\n",
2013 				   ap->port_no);
2014 	}
2015 
2016 	if (pp->fbs_supported) {
2017 		dma_sz = AHCI_PORT_PRIV_FBS_DMA_SZ;
2018 		rx_fis_sz = AHCI_RX_FIS_SZ * 16;
2019 	} else {
2020 		dma_sz = AHCI_PORT_PRIV_DMA_SZ;
2021 		rx_fis_sz = AHCI_RX_FIS_SZ;
2022 	}
2023 
2024 	mem = dmam_alloc_coherent(dev, dma_sz, &mem_dma, GFP_KERNEL);
2025 	if (!mem)
2026 		return -ENOMEM;
2027 	memset(mem, 0, dma_sz);
2028 
2029 	/*
2030 	 * First item in chunk of DMA memory: 32-slot command table,
2031 	 * 32 bytes each in size
2032 	 */
2033 	pp->cmd_slot = mem;
2034 	pp->cmd_slot_dma = mem_dma;
2035 
2036 	mem += AHCI_CMD_SLOT_SZ;
2037 	mem_dma += AHCI_CMD_SLOT_SZ;
2038 
2039 	/*
2040 	 * Second item: Received-FIS area
2041 	 */
2042 	pp->rx_fis = mem;
2043 	pp->rx_fis_dma = mem_dma;
2044 
2045 	mem += rx_fis_sz;
2046 	mem_dma += rx_fis_sz;
2047 
2048 	/*
2049 	 * Third item: data area for storing a single command
2050 	 * and its scatter-gather table
2051 	 */
2052 	pp->cmd_tbl = mem;
2053 	pp->cmd_tbl_dma = mem_dma;
2054 
2055 	/*
2056 	 * Save off initial list of interrupts to be enabled.
2057 	 * This could be changed later
2058 	 */
2059 	pp->intr_mask = DEF_PORT_IRQ;
2060 
2061 	ap->private_data = pp;
2062 
2063 	/* engage engines, captain */
2064 	return ahci_port_resume(ap);
2065 }
2066 
2067 static void ahci_port_stop(struct ata_port *ap)
2068 {
2069 	const char *emsg = NULL;
2070 	int rc;
2071 
2072 	/* de-initialize port */
2073 	rc = ahci_deinit_port(ap, &emsg);
2074 	if (rc)
2075 		ata_port_printk(ap, KERN_WARNING, "%s (%d)\n", emsg, rc);
2076 }
2077 
2078 void ahci_print_info(struct ata_host *host, const char *scc_s)
2079 {
2080 	struct ahci_host_priv *hpriv = host->private_data;
2081 	void __iomem *mmio = hpriv->mmio;
2082 	u32 vers, cap, cap2, impl, speed;
2083 	const char *speed_s;
2084 
2085 	vers = readl(mmio + HOST_VERSION);
2086 	cap = hpriv->cap;
2087 	cap2 = hpriv->cap2;
2088 	impl = hpriv->port_map;
2089 
2090 	speed = (cap >> 20) & 0xf;
2091 	if (speed == 1)
2092 		speed_s = "1.5";
2093 	else if (speed == 2)
2094 		speed_s = "3";
2095 	else if (speed == 3)
2096 		speed_s = "6";
2097 	else
2098 		speed_s = "?";
2099 
2100 	dev_info(host->dev,
2101 		"AHCI %02x%02x.%02x%02x "
2102 		"%u slots %u ports %s Gbps 0x%x impl %s mode\n"
2103 		,
2104 
2105 		(vers >> 24) & 0xff,
2106 		(vers >> 16) & 0xff,
2107 		(vers >> 8) & 0xff,
2108 		vers & 0xff,
2109 
2110 		((cap >> 8) & 0x1f) + 1,
2111 		(cap & 0x1f) + 1,
2112 		speed_s,
2113 		impl,
2114 		scc_s);
2115 
2116 	dev_info(host->dev,
2117 		"flags: "
2118 		"%s%s%s%s%s%s%s"
2119 		"%s%s%s%s%s%s%s"
2120 		"%s%s%s%s%s%s\n"
2121 		,
2122 
2123 		cap & HOST_CAP_64 ? "64bit " : "",
2124 		cap & HOST_CAP_NCQ ? "ncq " : "",
2125 		cap & HOST_CAP_SNTF ? "sntf " : "",
2126 		cap & HOST_CAP_MPS ? "ilck " : "",
2127 		cap & HOST_CAP_SSS ? "stag " : "",
2128 		cap & HOST_CAP_ALPM ? "pm " : "",
2129 		cap & HOST_CAP_LED ? "led " : "",
2130 		cap & HOST_CAP_CLO ? "clo " : "",
2131 		cap & HOST_CAP_ONLY ? "only " : "",
2132 		cap & HOST_CAP_PMP ? "pmp " : "",
2133 		cap & HOST_CAP_FBS ? "fbs " : "",
2134 		cap & HOST_CAP_PIO_MULTI ? "pio " : "",
2135 		cap & HOST_CAP_SSC ? "slum " : "",
2136 		cap & HOST_CAP_PART ? "part " : "",
2137 		cap & HOST_CAP_CCC ? "ccc " : "",
2138 		cap & HOST_CAP_EMS ? "ems " : "",
2139 		cap & HOST_CAP_SXS ? "sxs " : "",
2140 		cap2 & HOST_CAP2_APST ? "apst " : "",
2141 		cap2 & HOST_CAP2_NVMHCI ? "nvmp " : "",
2142 		cap2 & HOST_CAP2_BOH ? "boh " : ""
2143 		);
2144 }
2145 EXPORT_SYMBOL_GPL(ahci_print_info);
2146 
2147 void ahci_set_em_messages(struct ahci_host_priv *hpriv,
2148 			  struct ata_port_info *pi)
2149 {
2150 	u8 messages;
2151 	void __iomem *mmio = hpriv->mmio;
2152 	u32 em_loc = readl(mmio + HOST_EM_LOC);
2153 	u32 em_ctl = readl(mmio + HOST_EM_CTL);
2154 
2155 	if (!ahci_em_messages || !(hpriv->cap & HOST_CAP_EMS))
2156 		return;
2157 
2158 	messages = (em_ctl & EM_CTRL_MSG_TYPE) >> 16;
2159 
2160 	if (messages) {
2161 		/* store em_loc */
2162 		hpriv->em_loc = ((em_loc >> 16) * 4);
2163 		hpriv->em_buf_sz = ((em_loc & 0xff) * 4);
2164 		hpriv->em_msg_type = messages;
2165 		pi->flags |= ATA_FLAG_EM;
2166 		if (!(em_ctl & EM_CTL_ALHD))
2167 			pi->flags |= ATA_FLAG_SW_ACTIVITY;
2168 	}
2169 }
2170 EXPORT_SYMBOL_GPL(ahci_set_em_messages);
2171 
2172 MODULE_AUTHOR("Jeff Garzik");
2173 MODULE_DESCRIPTION("Common AHCI SATA low-level routines");
2174 MODULE_LICENSE("GPL");
2175