xref: /openbmc/linux/drivers/ata/libahci.c (revision 2596e07a)
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 <linux/pci.h>
47 #include "ahci.h"
48 #include "libata.h"
49 
50 static int ahci_skip_host_reset;
51 int ahci_ignore_sss;
52 EXPORT_SYMBOL_GPL(ahci_ignore_sss);
53 
54 module_param_named(skip_host_reset, ahci_skip_host_reset, int, 0444);
55 MODULE_PARM_DESC(skip_host_reset, "skip global host reset (0=don't skip, 1=skip)");
56 
57 module_param_named(ignore_sss, ahci_ignore_sss, int, 0444);
58 MODULE_PARM_DESC(ignore_sss, "Ignore staggered spinup flag (0=don't ignore, 1=ignore)");
59 
60 static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
61 			unsigned hints);
62 static ssize_t ahci_led_show(struct ata_port *ap, char *buf);
63 static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
64 			      size_t size);
65 static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
66 					ssize_t size);
67 
68 
69 
70 static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val);
71 static int ahci_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val);
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_set_aggressive_devslp(struct ata_port *ap, bool sleep);
80 static void ahci_enable_fbs(struct ata_port *ap);
81 static void ahci_disable_fbs(struct ata_port *ap);
82 static void ahci_pmp_attach(struct ata_port *ap);
83 static void ahci_pmp_detach(struct ata_port *ap);
84 static int ahci_softreset(struct ata_link *link, unsigned int *class,
85 			  unsigned long deadline);
86 static int ahci_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
87 			  unsigned long deadline);
88 static int ahci_hardreset(struct ata_link *link, unsigned int *class,
89 			  unsigned long deadline);
90 static void ahci_postreset(struct ata_link *link, unsigned int *class);
91 static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
92 static void ahci_dev_config(struct ata_device *dev);
93 #ifdef CONFIG_PM
94 static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg);
95 #endif
96 static ssize_t ahci_activity_show(struct ata_device *dev, char *buf);
97 static ssize_t ahci_activity_store(struct ata_device *dev,
98 				   enum sw_activity val);
99 static void ahci_init_sw_activity(struct ata_link *link);
100 
101 static ssize_t ahci_show_host_caps(struct device *dev,
102 				   struct device_attribute *attr, char *buf);
103 static ssize_t ahci_show_host_cap2(struct device *dev,
104 				   struct device_attribute *attr, char *buf);
105 static ssize_t ahci_show_host_version(struct device *dev,
106 				      struct device_attribute *attr, char *buf);
107 static ssize_t ahci_show_port_cmd(struct device *dev,
108 				  struct device_attribute *attr, char *buf);
109 static ssize_t ahci_read_em_buffer(struct device *dev,
110 				   struct device_attribute *attr, char *buf);
111 static ssize_t ahci_store_em_buffer(struct device *dev,
112 				    struct device_attribute *attr,
113 				    const char *buf, size_t size);
114 static ssize_t ahci_show_em_supported(struct device *dev,
115 				      struct device_attribute *attr, char *buf);
116 
117 static DEVICE_ATTR(ahci_host_caps, S_IRUGO, ahci_show_host_caps, NULL);
118 static DEVICE_ATTR(ahci_host_cap2, S_IRUGO, ahci_show_host_cap2, NULL);
119 static DEVICE_ATTR(ahci_host_version, S_IRUGO, ahci_show_host_version, NULL);
120 static DEVICE_ATTR(ahci_port_cmd, S_IRUGO, ahci_show_port_cmd, NULL);
121 static DEVICE_ATTR(em_buffer, S_IWUSR | S_IRUGO,
122 		   ahci_read_em_buffer, ahci_store_em_buffer);
123 static DEVICE_ATTR(em_message_supported, S_IRUGO, ahci_show_em_supported, NULL);
124 
125 struct device_attribute *ahci_shost_attrs[] = {
126 	&dev_attr_link_power_management_policy,
127 	&dev_attr_em_message_type,
128 	&dev_attr_em_message,
129 	&dev_attr_ahci_host_caps,
130 	&dev_attr_ahci_host_cap2,
131 	&dev_attr_ahci_host_version,
132 	&dev_attr_ahci_port_cmd,
133 	&dev_attr_em_buffer,
134 	&dev_attr_em_message_supported,
135 	NULL
136 };
137 EXPORT_SYMBOL_GPL(ahci_shost_attrs);
138 
139 struct device_attribute *ahci_sdev_attrs[] = {
140 	&dev_attr_sw_activity,
141 	&dev_attr_unload_heads,
142 	NULL
143 };
144 EXPORT_SYMBOL_GPL(ahci_sdev_attrs);
145 
146 struct ata_port_operations ahci_ops = {
147 	.inherits		= &sata_pmp_port_ops,
148 
149 	.qc_defer		= ahci_pmp_qc_defer,
150 	.qc_prep		= ahci_qc_prep,
151 	.qc_issue		= ahci_qc_issue,
152 	.qc_fill_rtf		= ahci_qc_fill_rtf,
153 
154 	.freeze			= ahci_freeze,
155 	.thaw			= ahci_thaw,
156 	.softreset		= ahci_softreset,
157 	.hardreset		= ahci_hardreset,
158 	.postreset		= ahci_postreset,
159 	.pmp_softreset		= ahci_softreset,
160 	.error_handler		= ahci_error_handler,
161 	.post_internal_cmd	= ahci_post_internal_cmd,
162 	.dev_config		= ahci_dev_config,
163 
164 	.scr_read		= ahci_scr_read,
165 	.scr_write		= ahci_scr_write,
166 	.pmp_attach		= ahci_pmp_attach,
167 	.pmp_detach		= ahci_pmp_detach,
168 
169 	.set_lpm		= ahci_set_lpm,
170 	.em_show		= ahci_led_show,
171 	.em_store		= ahci_led_store,
172 	.sw_activity_show	= ahci_activity_show,
173 	.sw_activity_store	= ahci_activity_store,
174 	.transmit_led_message	= ahci_transmit_led_message,
175 #ifdef CONFIG_PM
176 	.port_suspend		= ahci_port_suspend,
177 	.port_resume		= ahci_port_resume,
178 #endif
179 	.port_start		= ahci_port_start,
180 	.port_stop		= ahci_port_stop,
181 };
182 EXPORT_SYMBOL_GPL(ahci_ops);
183 
184 struct ata_port_operations ahci_pmp_retry_srst_ops = {
185 	.inherits		= &ahci_ops,
186 	.softreset		= ahci_pmp_retry_softreset,
187 };
188 EXPORT_SYMBOL_GPL(ahci_pmp_retry_srst_ops);
189 
190 static bool ahci_em_messages __read_mostly = true;
191 EXPORT_SYMBOL_GPL(ahci_em_messages);
192 module_param(ahci_em_messages, bool, 0444);
193 /* add other LED protocol types when they become supported */
194 MODULE_PARM_DESC(ahci_em_messages,
195 	"AHCI Enclosure Management Message control (0 = off, 1 = on)");
196 
197 /* device sleep idle timeout in ms */
198 static int devslp_idle_timeout __read_mostly = 1000;
199 module_param(devslp_idle_timeout, int, 0644);
200 MODULE_PARM_DESC(devslp_idle_timeout, "device sleep idle timeout");
201 
202 static void ahci_enable_ahci(void __iomem *mmio)
203 {
204 	int i;
205 	u32 tmp;
206 
207 	/* turn on AHCI_EN */
208 	tmp = readl(mmio + HOST_CTL);
209 	if (tmp & HOST_AHCI_EN)
210 		return;
211 
212 	/* Some controllers need AHCI_EN to be written multiple times.
213 	 * Try a few times before giving up.
214 	 */
215 	for (i = 0; i < 5; i++) {
216 		tmp |= HOST_AHCI_EN;
217 		writel(tmp, mmio + HOST_CTL);
218 		tmp = readl(mmio + HOST_CTL);	/* flush && sanity check */
219 		if (tmp & HOST_AHCI_EN)
220 			return;
221 		msleep(10);
222 	}
223 
224 	WARN_ON(1);
225 }
226 
227 static ssize_t ahci_show_host_caps(struct device *dev,
228 				   struct device_attribute *attr, char *buf)
229 {
230 	struct Scsi_Host *shost = class_to_shost(dev);
231 	struct ata_port *ap = ata_shost_to_port(shost);
232 	struct ahci_host_priv *hpriv = ap->host->private_data;
233 
234 	return sprintf(buf, "%x\n", hpriv->cap);
235 }
236 
237 static ssize_t ahci_show_host_cap2(struct device *dev,
238 				   struct device_attribute *attr, char *buf)
239 {
240 	struct Scsi_Host *shost = class_to_shost(dev);
241 	struct ata_port *ap = ata_shost_to_port(shost);
242 	struct ahci_host_priv *hpriv = ap->host->private_data;
243 
244 	return sprintf(buf, "%x\n", hpriv->cap2);
245 }
246 
247 static ssize_t ahci_show_host_version(struct device *dev,
248 				   struct device_attribute *attr, char *buf)
249 {
250 	struct Scsi_Host *shost = class_to_shost(dev);
251 	struct ata_port *ap = ata_shost_to_port(shost);
252 	struct ahci_host_priv *hpriv = ap->host->private_data;
253 	void __iomem *mmio = hpriv->mmio;
254 
255 	return sprintf(buf, "%x\n", readl(mmio + HOST_VERSION));
256 }
257 
258 static ssize_t ahci_show_port_cmd(struct device *dev,
259 				  struct device_attribute *attr, char *buf)
260 {
261 	struct Scsi_Host *shost = class_to_shost(dev);
262 	struct ata_port *ap = ata_shost_to_port(shost);
263 	void __iomem *port_mmio = ahci_port_base(ap);
264 
265 	return sprintf(buf, "%x\n", readl(port_mmio + PORT_CMD));
266 }
267 
268 static ssize_t ahci_read_em_buffer(struct device *dev,
269 				   struct device_attribute *attr, char *buf)
270 {
271 	struct Scsi_Host *shost = class_to_shost(dev);
272 	struct ata_port *ap = ata_shost_to_port(shost);
273 	struct ahci_host_priv *hpriv = ap->host->private_data;
274 	void __iomem *mmio = hpriv->mmio;
275 	void __iomem *em_mmio = mmio + hpriv->em_loc;
276 	u32 em_ctl, msg;
277 	unsigned long flags;
278 	size_t count;
279 	int i;
280 
281 	spin_lock_irqsave(ap->lock, flags);
282 
283 	em_ctl = readl(mmio + HOST_EM_CTL);
284 	if (!(ap->flags & ATA_FLAG_EM) || em_ctl & EM_CTL_XMT ||
285 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO)) {
286 		spin_unlock_irqrestore(ap->lock, flags);
287 		return -EINVAL;
288 	}
289 
290 	if (!(em_ctl & EM_CTL_MR)) {
291 		spin_unlock_irqrestore(ap->lock, flags);
292 		return -EAGAIN;
293 	}
294 
295 	if (!(em_ctl & EM_CTL_SMB))
296 		em_mmio += hpriv->em_buf_sz;
297 
298 	count = hpriv->em_buf_sz;
299 
300 	/* the count should not be larger than PAGE_SIZE */
301 	if (count > PAGE_SIZE) {
302 		if (printk_ratelimit())
303 			ata_port_warn(ap,
304 				      "EM read buffer size too large: "
305 				      "buffer size %u, page size %lu\n",
306 				      hpriv->em_buf_sz, PAGE_SIZE);
307 		count = PAGE_SIZE;
308 	}
309 
310 	for (i = 0; i < count; i += 4) {
311 		msg = readl(em_mmio + i);
312 		buf[i] = msg & 0xff;
313 		buf[i + 1] = (msg >> 8) & 0xff;
314 		buf[i + 2] = (msg >> 16) & 0xff;
315 		buf[i + 3] = (msg >> 24) & 0xff;
316 	}
317 
318 	spin_unlock_irqrestore(ap->lock, flags);
319 
320 	return i;
321 }
322 
323 static ssize_t ahci_store_em_buffer(struct device *dev,
324 				    struct device_attribute *attr,
325 				    const char *buf, size_t size)
326 {
327 	struct Scsi_Host *shost = class_to_shost(dev);
328 	struct ata_port *ap = ata_shost_to_port(shost);
329 	struct ahci_host_priv *hpriv = ap->host->private_data;
330 	void __iomem *mmio = hpriv->mmio;
331 	void __iomem *em_mmio = mmio + hpriv->em_loc;
332 	const unsigned char *msg_buf = buf;
333 	u32 em_ctl, msg;
334 	unsigned long flags;
335 	int i;
336 
337 	/* check size validity */
338 	if (!(ap->flags & ATA_FLAG_EM) ||
339 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO) ||
340 	    size % 4 || size > hpriv->em_buf_sz)
341 		return -EINVAL;
342 
343 	spin_lock_irqsave(ap->lock, flags);
344 
345 	em_ctl = readl(mmio + HOST_EM_CTL);
346 	if (em_ctl & EM_CTL_TM) {
347 		spin_unlock_irqrestore(ap->lock, flags);
348 		return -EBUSY;
349 	}
350 
351 	for (i = 0; i < size; i += 4) {
352 		msg = msg_buf[i] | msg_buf[i + 1] << 8 |
353 		      msg_buf[i + 2] << 16 | msg_buf[i + 3] << 24;
354 		writel(msg, em_mmio + i);
355 	}
356 
357 	writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
358 
359 	spin_unlock_irqrestore(ap->lock, flags);
360 
361 	return size;
362 }
363 
364 static ssize_t ahci_show_em_supported(struct device *dev,
365 				      struct device_attribute *attr, char *buf)
366 {
367 	struct Scsi_Host *shost = class_to_shost(dev);
368 	struct ata_port *ap = ata_shost_to_port(shost);
369 	struct ahci_host_priv *hpriv = ap->host->private_data;
370 	void __iomem *mmio = hpriv->mmio;
371 	u32 em_ctl;
372 
373 	em_ctl = readl(mmio + HOST_EM_CTL);
374 
375 	return sprintf(buf, "%s%s%s%s\n",
376 		       em_ctl & EM_CTL_LED ? "led " : "",
377 		       em_ctl & EM_CTL_SAFTE ? "saf-te " : "",
378 		       em_ctl & EM_CTL_SES ? "ses-2 " : "",
379 		       em_ctl & EM_CTL_SGPIO ? "sgpio " : "");
380 }
381 
382 /**
383  *	ahci_save_initial_config - Save and fixup initial config values
384  *	@dev: target AHCI device
385  *	@hpriv: host private area to store config values
386  *
387  *	Some registers containing configuration info might be setup by
388  *	BIOS and might be cleared on reset.  This function saves the
389  *	initial values of those registers into @hpriv such that they
390  *	can be restored after controller reset.
391  *
392  *	If inconsistent, config values are fixed up by this function.
393  *
394  *	If it is not set already this function sets hpriv->start_engine to
395  *	ahci_start_engine.
396  *
397  *	LOCKING:
398  *	None.
399  */
400 void ahci_save_initial_config(struct device *dev, struct ahci_host_priv *hpriv)
401 {
402 	void __iomem *mmio = hpriv->mmio;
403 	u32 cap, cap2, vers, port_map;
404 	int i;
405 
406 	/* make sure AHCI mode is enabled before accessing CAP */
407 	ahci_enable_ahci(mmio);
408 
409 	/* Values prefixed with saved_ are written back to host after
410 	 * reset.  Values without are used for driver operation.
411 	 */
412 	hpriv->saved_cap = cap = readl(mmio + HOST_CAP);
413 	hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL);
414 
415 	/* CAP2 register is only defined for AHCI 1.2 and later */
416 	vers = readl(mmio + HOST_VERSION);
417 	if ((vers >> 16) > 1 ||
418 	   ((vers >> 16) == 1 && (vers & 0xFFFF) >= 0x200))
419 		hpriv->saved_cap2 = cap2 = readl(mmio + HOST_CAP2);
420 	else
421 		hpriv->saved_cap2 = cap2 = 0;
422 
423 	/* some chips have errata preventing 64bit use */
424 	if ((cap & HOST_CAP_64) && (hpriv->flags & AHCI_HFLAG_32BIT_ONLY)) {
425 		dev_info(dev, "controller can't do 64bit DMA, forcing 32bit\n");
426 		cap &= ~HOST_CAP_64;
427 	}
428 
429 	if ((cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_NO_NCQ)) {
430 		dev_info(dev, "controller can't do NCQ, turning off CAP_NCQ\n");
431 		cap &= ~HOST_CAP_NCQ;
432 	}
433 
434 	if (!(cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_YES_NCQ)) {
435 		dev_info(dev, "controller can do NCQ, turning on CAP_NCQ\n");
436 		cap |= HOST_CAP_NCQ;
437 	}
438 
439 	if ((cap & HOST_CAP_PMP) && (hpriv->flags & AHCI_HFLAG_NO_PMP)) {
440 		dev_info(dev, "controller can't do PMP, turning off CAP_PMP\n");
441 		cap &= ~HOST_CAP_PMP;
442 	}
443 
444 	if ((cap & HOST_CAP_SNTF) && (hpriv->flags & AHCI_HFLAG_NO_SNTF)) {
445 		dev_info(dev,
446 			 "controller can't do SNTF, turning off CAP_SNTF\n");
447 		cap &= ~HOST_CAP_SNTF;
448 	}
449 
450 	if ((cap2 & HOST_CAP2_SDS) && (hpriv->flags & AHCI_HFLAG_NO_DEVSLP)) {
451 		dev_info(dev,
452 			 "controller can't do DEVSLP, turning off\n");
453 		cap2 &= ~HOST_CAP2_SDS;
454 		cap2 &= ~HOST_CAP2_SADM;
455 	}
456 
457 	if (!(cap & HOST_CAP_FBS) && (hpriv->flags & AHCI_HFLAG_YES_FBS)) {
458 		dev_info(dev, "controller can do FBS, turning on CAP_FBS\n");
459 		cap |= HOST_CAP_FBS;
460 	}
461 
462 	if ((cap & HOST_CAP_FBS) && (hpriv->flags & AHCI_HFLAG_NO_FBS)) {
463 		dev_info(dev, "controller can't do FBS, turning off CAP_FBS\n");
464 		cap &= ~HOST_CAP_FBS;
465 	}
466 
467 	if (hpriv->force_port_map && port_map != hpriv->force_port_map) {
468 		dev_info(dev, "forcing port_map 0x%x -> 0x%x\n",
469 			 port_map, hpriv->force_port_map);
470 		port_map = hpriv->force_port_map;
471 	}
472 
473 	if (hpriv->mask_port_map) {
474 		dev_warn(dev, "masking port_map 0x%x -> 0x%x\n",
475 			port_map,
476 			port_map & hpriv->mask_port_map);
477 		port_map &= hpriv->mask_port_map;
478 	}
479 
480 	/* cross check port_map and cap.n_ports */
481 	if (port_map) {
482 		int map_ports = 0;
483 
484 		for (i = 0; i < AHCI_MAX_PORTS; i++)
485 			if (port_map & (1 << i))
486 				map_ports++;
487 
488 		/* If PI has more ports than n_ports, whine, clear
489 		 * port_map and let it be generated from n_ports.
490 		 */
491 		if (map_ports > ahci_nr_ports(cap)) {
492 			dev_warn(dev,
493 				 "implemented port map (0x%x) contains more ports than nr_ports (%u), using nr_ports\n",
494 				 port_map, ahci_nr_ports(cap));
495 			port_map = 0;
496 		}
497 	}
498 
499 	/* fabricate port_map from cap.nr_ports for < AHCI 1.3 */
500 	if (!port_map && vers < 0x10300) {
501 		port_map = (1 << ahci_nr_ports(cap)) - 1;
502 		dev_warn(dev, "forcing PORTS_IMPL to 0x%x\n", port_map);
503 
504 		/* write the fixed up value to the PI register */
505 		hpriv->saved_port_map = port_map;
506 	}
507 
508 	/* record values to use during operation */
509 	hpriv->cap = cap;
510 	hpriv->cap2 = cap2;
511 	hpriv->port_map = port_map;
512 
513 	if (!hpriv->start_engine)
514 		hpriv->start_engine = ahci_start_engine;
515 }
516 EXPORT_SYMBOL_GPL(ahci_save_initial_config);
517 
518 /**
519  *	ahci_restore_initial_config - Restore initial config
520  *	@host: target ATA host
521  *
522  *	Restore initial config stored by ahci_save_initial_config().
523  *
524  *	LOCKING:
525  *	None.
526  */
527 static void ahci_restore_initial_config(struct ata_host *host)
528 {
529 	struct ahci_host_priv *hpriv = host->private_data;
530 	void __iomem *mmio = hpriv->mmio;
531 
532 	writel(hpriv->saved_cap, mmio + HOST_CAP);
533 	if (hpriv->saved_cap2)
534 		writel(hpriv->saved_cap2, mmio + HOST_CAP2);
535 	writel(hpriv->saved_port_map, mmio + HOST_PORTS_IMPL);
536 	(void) readl(mmio + HOST_PORTS_IMPL);	/* flush */
537 }
538 
539 static unsigned ahci_scr_offset(struct ata_port *ap, unsigned int sc_reg)
540 {
541 	static const int offset[] = {
542 		[SCR_STATUS]		= PORT_SCR_STAT,
543 		[SCR_CONTROL]		= PORT_SCR_CTL,
544 		[SCR_ERROR]		= PORT_SCR_ERR,
545 		[SCR_ACTIVE]		= PORT_SCR_ACT,
546 		[SCR_NOTIFICATION]	= PORT_SCR_NTF,
547 	};
548 	struct ahci_host_priv *hpriv = ap->host->private_data;
549 
550 	if (sc_reg < ARRAY_SIZE(offset) &&
551 	    (sc_reg != SCR_NOTIFICATION || (hpriv->cap & HOST_CAP_SNTF)))
552 		return offset[sc_reg];
553 	return 0;
554 }
555 
556 static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val)
557 {
558 	void __iomem *port_mmio = ahci_port_base(link->ap);
559 	int offset = ahci_scr_offset(link->ap, sc_reg);
560 
561 	if (offset) {
562 		*val = readl(port_mmio + offset);
563 		return 0;
564 	}
565 	return -EINVAL;
566 }
567 
568 static int ahci_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val)
569 {
570 	void __iomem *port_mmio = ahci_port_base(link->ap);
571 	int offset = ahci_scr_offset(link->ap, sc_reg);
572 
573 	if (offset) {
574 		writel(val, port_mmio + offset);
575 		return 0;
576 	}
577 	return -EINVAL;
578 }
579 
580 void ahci_start_engine(struct ata_port *ap)
581 {
582 	void __iomem *port_mmio = ahci_port_base(ap);
583 	u32 tmp;
584 
585 	/* start DMA */
586 	tmp = readl(port_mmio + PORT_CMD);
587 	tmp |= PORT_CMD_START;
588 	writel(tmp, port_mmio + PORT_CMD);
589 	readl(port_mmio + PORT_CMD); /* flush */
590 }
591 EXPORT_SYMBOL_GPL(ahci_start_engine);
592 
593 int ahci_stop_engine(struct ata_port *ap)
594 {
595 	void __iomem *port_mmio = ahci_port_base(ap);
596 	struct ahci_host_priv *hpriv = ap->host->private_data;
597 	u32 tmp;
598 
599 	/*
600 	 * On some controllers, stopping a port's DMA engine while the port
601 	 * is in ALPM state (partial or slumber) results in failures on
602 	 * subsequent DMA engine starts.  For those controllers, put the
603 	 * port back in active state before stopping its DMA engine.
604 	 */
605 	if ((hpriv->flags & AHCI_HFLAG_WAKE_BEFORE_STOP) &&
606 	    (ap->link.lpm_policy > ATA_LPM_MAX_POWER) &&
607 	    ahci_set_lpm(&ap->link, ATA_LPM_MAX_POWER, ATA_LPM_WAKE_ONLY)) {
608 		dev_err(ap->host->dev, "Failed to wake up port before engine stop\n");
609 		return -EIO;
610 	}
611 
612 	tmp = readl(port_mmio + PORT_CMD);
613 
614 	/* check if the HBA is idle */
615 	if ((tmp & (PORT_CMD_START | PORT_CMD_LIST_ON)) == 0)
616 		return 0;
617 
618 	/* setting HBA to idle */
619 	tmp &= ~PORT_CMD_START;
620 	writel(tmp, port_mmio + PORT_CMD);
621 
622 	/* wait for engine to stop. This could be as long as 500 msec */
623 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
624 				PORT_CMD_LIST_ON, PORT_CMD_LIST_ON, 1, 500);
625 	if (tmp & PORT_CMD_LIST_ON)
626 		return -EIO;
627 
628 	return 0;
629 }
630 EXPORT_SYMBOL_GPL(ahci_stop_engine);
631 
632 void ahci_start_fis_rx(struct ata_port *ap)
633 {
634 	void __iomem *port_mmio = ahci_port_base(ap);
635 	struct ahci_host_priv *hpriv = ap->host->private_data;
636 	struct ahci_port_priv *pp = ap->private_data;
637 	u32 tmp;
638 
639 	/* set FIS registers */
640 	if (hpriv->cap & HOST_CAP_64)
641 		writel((pp->cmd_slot_dma >> 16) >> 16,
642 		       port_mmio + PORT_LST_ADDR_HI);
643 	writel(pp->cmd_slot_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);
644 
645 	if (hpriv->cap & HOST_CAP_64)
646 		writel((pp->rx_fis_dma >> 16) >> 16,
647 		       port_mmio + PORT_FIS_ADDR_HI);
648 	writel(pp->rx_fis_dma & 0xffffffff, port_mmio + PORT_FIS_ADDR);
649 
650 	/* enable FIS reception */
651 	tmp = readl(port_mmio + PORT_CMD);
652 	tmp |= PORT_CMD_FIS_RX;
653 	writel(tmp, port_mmio + PORT_CMD);
654 
655 	/* flush */
656 	readl(port_mmio + PORT_CMD);
657 }
658 EXPORT_SYMBOL_GPL(ahci_start_fis_rx);
659 
660 static int ahci_stop_fis_rx(struct ata_port *ap)
661 {
662 	void __iomem *port_mmio = ahci_port_base(ap);
663 	u32 tmp;
664 
665 	/* disable FIS reception */
666 	tmp = readl(port_mmio + PORT_CMD);
667 	tmp &= ~PORT_CMD_FIS_RX;
668 	writel(tmp, port_mmio + PORT_CMD);
669 
670 	/* wait for completion, spec says 500ms, give it 1000 */
671 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD, PORT_CMD_FIS_ON,
672 				PORT_CMD_FIS_ON, 10, 1000);
673 	if (tmp & PORT_CMD_FIS_ON)
674 		return -EBUSY;
675 
676 	return 0;
677 }
678 
679 static void ahci_power_up(struct ata_port *ap)
680 {
681 	struct ahci_host_priv *hpriv = ap->host->private_data;
682 	void __iomem *port_mmio = ahci_port_base(ap);
683 	u32 cmd;
684 
685 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
686 
687 	/* spin up device */
688 	if (hpriv->cap & HOST_CAP_SSS) {
689 		cmd |= PORT_CMD_SPIN_UP;
690 		writel(cmd, port_mmio + PORT_CMD);
691 	}
692 
693 	/* wake up link */
694 	writel(cmd | PORT_CMD_ICC_ACTIVE, port_mmio + PORT_CMD);
695 }
696 
697 static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
698 			unsigned int hints)
699 {
700 	struct ata_port *ap = link->ap;
701 	struct ahci_host_priv *hpriv = ap->host->private_data;
702 	struct ahci_port_priv *pp = ap->private_data;
703 	void __iomem *port_mmio = ahci_port_base(ap);
704 
705 	if (policy != ATA_LPM_MAX_POWER) {
706 		/* wakeup flag only applies to the max power policy */
707 		hints &= ~ATA_LPM_WAKE_ONLY;
708 
709 		/*
710 		 * Disable interrupts on Phy Ready. This keeps us from
711 		 * getting woken up due to spurious phy ready
712 		 * interrupts.
713 		 */
714 		pp->intr_mask &= ~PORT_IRQ_PHYRDY;
715 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
716 
717 		sata_link_scr_lpm(link, policy, false);
718 	}
719 
720 	if (hpriv->cap & HOST_CAP_ALPM) {
721 		u32 cmd = readl(port_mmio + PORT_CMD);
722 
723 		if (policy == ATA_LPM_MAX_POWER || !(hints & ATA_LPM_HIPM)) {
724 			if (!(hints & ATA_LPM_WAKE_ONLY))
725 				cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE);
726 			cmd |= PORT_CMD_ICC_ACTIVE;
727 
728 			writel(cmd, port_mmio + PORT_CMD);
729 			readl(port_mmio + PORT_CMD);
730 
731 			/* wait 10ms to be sure we've come out of LPM state */
732 			ata_msleep(ap, 10);
733 
734 			if (hints & ATA_LPM_WAKE_ONLY)
735 				return 0;
736 		} else {
737 			cmd |= PORT_CMD_ALPE;
738 			if (policy == ATA_LPM_MIN_POWER)
739 				cmd |= PORT_CMD_ASP;
740 
741 			/* write out new cmd value */
742 			writel(cmd, port_mmio + PORT_CMD);
743 		}
744 	}
745 
746 	/* set aggressive device sleep */
747 	if ((hpriv->cap2 & HOST_CAP2_SDS) &&
748 	    (hpriv->cap2 & HOST_CAP2_SADM) &&
749 	    (link->device->flags & ATA_DFLAG_DEVSLP)) {
750 		if (policy == ATA_LPM_MIN_POWER)
751 			ahci_set_aggressive_devslp(ap, true);
752 		else
753 			ahci_set_aggressive_devslp(ap, false);
754 	}
755 
756 	if (policy == ATA_LPM_MAX_POWER) {
757 		sata_link_scr_lpm(link, policy, false);
758 
759 		/* turn PHYRDY IRQ back on */
760 		pp->intr_mask |= PORT_IRQ_PHYRDY;
761 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
762 	}
763 
764 	return 0;
765 }
766 
767 #ifdef CONFIG_PM
768 static void ahci_power_down(struct ata_port *ap)
769 {
770 	struct ahci_host_priv *hpriv = ap->host->private_data;
771 	void __iomem *port_mmio = ahci_port_base(ap);
772 	u32 cmd, scontrol;
773 
774 	if (!(hpriv->cap & HOST_CAP_SSS))
775 		return;
776 
777 	/* put device into listen mode, first set PxSCTL.DET to 0 */
778 	scontrol = readl(port_mmio + PORT_SCR_CTL);
779 	scontrol &= ~0xf;
780 	writel(scontrol, port_mmio + PORT_SCR_CTL);
781 
782 	/* then set PxCMD.SUD to 0 */
783 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
784 	cmd &= ~PORT_CMD_SPIN_UP;
785 	writel(cmd, port_mmio + PORT_CMD);
786 }
787 #endif
788 
789 static void ahci_start_port(struct ata_port *ap)
790 {
791 	struct ahci_host_priv *hpriv = ap->host->private_data;
792 	struct ahci_port_priv *pp = ap->private_data;
793 	struct ata_link *link;
794 	struct ahci_em_priv *emp;
795 	ssize_t rc;
796 	int i;
797 
798 	/* enable FIS reception */
799 	ahci_start_fis_rx(ap);
800 
801 	/* enable DMA */
802 	if (!(hpriv->flags & AHCI_HFLAG_DELAY_ENGINE))
803 		hpriv->start_engine(ap);
804 
805 	/* turn on LEDs */
806 	if (ap->flags & ATA_FLAG_EM) {
807 		ata_for_each_link(link, ap, EDGE) {
808 			emp = &pp->em_priv[link->pmp];
809 
810 			/* EM Transmit bit maybe busy during init */
811 			for (i = 0; i < EM_MAX_RETRY; i++) {
812 				rc = ap->ops->transmit_led_message(ap,
813 							       emp->led_state,
814 							       4);
815 				/*
816 				 * If busy, give a breather but do not
817 				 * release EH ownership by using msleep()
818 				 * instead of ata_msleep().  EM Transmit
819 				 * bit is busy for the whole host and
820 				 * releasing ownership will cause other
821 				 * ports to fail the same way.
822 				 */
823 				if (rc == -EBUSY)
824 					msleep(1);
825 				else
826 					break;
827 			}
828 		}
829 	}
830 
831 	if (ap->flags & ATA_FLAG_SW_ACTIVITY)
832 		ata_for_each_link(link, ap, EDGE)
833 			ahci_init_sw_activity(link);
834 
835 }
836 
837 static int ahci_deinit_port(struct ata_port *ap, const char **emsg)
838 {
839 	int rc;
840 
841 	/* disable DMA */
842 	rc = ahci_stop_engine(ap);
843 	if (rc) {
844 		*emsg = "failed to stop engine";
845 		return rc;
846 	}
847 
848 	/* disable FIS reception */
849 	rc = ahci_stop_fis_rx(ap);
850 	if (rc) {
851 		*emsg = "failed stop FIS RX";
852 		return rc;
853 	}
854 
855 	return 0;
856 }
857 
858 int ahci_reset_controller(struct ata_host *host)
859 {
860 	struct ahci_host_priv *hpriv = host->private_data;
861 	void __iomem *mmio = hpriv->mmio;
862 	u32 tmp;
863 
864 	/* we must be in AHCI mode, before using anything
865 	 * AHCI-specific, such as HOST_RESET.
866 	 */
867 	ahci_enable_ahci(mmio);
868 
869 	/* global controller reset */
870 	if (!ahci_skip_host_reset) {
871 		tmp = readl(mmio + HOST_CTL);
872 		if ((tmp & HOST_RESET) == 0) {
873 			writel(tmp | HOST_RESET, mmio + HOST_CTL);
874 			readl(mmio + HOST_CTL); /* flush */
875 		}
876 
877 		/*
878 		 * to perform host reset, OS should set HOST_RESET
879 		 * and poll until this bit is read to be "0".
880 		 * reset must complete within 1 second, or
881 		 * the hardware should be considered fried.
882 		 */
883 		tmp = ata_wait_register(NULL, mmio + HOST_CTL, HOST_RESET,
884 					HOST_RESET, 10, 1000);
885 
886 		if (tmp & HOST_RESET) {
887 			dev_err(host->dev, "controller reset failed (0x%x)\n",
888 				tmp);
889 			return -EIO;
890 		}
891 
892 		/* turn on AHCI mode */
893 		ahci_enable_ahci(mmio);
894 
895 		/* Some registers might be cleared on reset.  Restore
896 		 * initial values.
897 		 */
898 		ahci_restore_initial_config(host);
899 	} else
900 		dev_info(host->dev, "skipping global host reset\n");
901 
902 	return 0;
903 }
904 EXPORT_SYMBOL_GPL(ahci_reset_controller);
905 
906 static void ahci_sw_activity(struct ata_link *link)
907 {
908 	struct ata_port *ap = link->ap;
909 	struct ahci_port_priv *pp = ap->private_data;
910 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
911 
912 	if (!(link->flags & ATA_LFLAG_SW_ACTIVITY))
913 		return;
914 
915 	emp->activity++;
916 	if (!timer_pending(&emp->timer))
917 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(10));
918 }
919 
920 static void ahci_sw_activity_blink(unsigned long arg)
921 {
922 	struct ata_link *link = (struct ata_link *)arg;
923 	struct ata_port *ap = link->ap;
924 	struct ahci_port_priv *pp = ap->private_data;
925 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
926 	unsigned long led_message = emp->led_state;
927 	u32 activity_led_state;
928 	unsigned long flags;
929 
930 	led_message &= EM_MSG_LED_VALUE;
931 	led_message |= ap->port_no | (link->pmp << 8);
932 
933 	/* check to see if we've had activity.  If so,
934 	 * toggle state of LED and reset timer.  If not,
935 	 * turn LED to desired idle state.
936 	 */
937 	spin_lock_irqsave(ap->lock, flags);
938 	if (emp->saved_activity != emp->activity) {
939 		emp->saved_activity = emp->activity;
940 		/* get the current LED state */
941 		activity_led_state = led_message & EM_MSG_LED_VALUE_ON;
942 
943 		if (activity_led_state)
944 			activity_led_state = 0;
945 		else
946 			activity_led_state = 1;
947 
948 		/* clear old state */
949 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
950 
951 		/* toggle state */
952 		led_message |= (activity_led_state << 16);
953 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(100));
954 	} else {
955 		/* switch to idle */
956 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
957 		if (emp->blink_policy == BLINK_OFF)
958 			led_message |= (1 << 16);
959 	}
960 	spin_unlock_irqrestore(ap->lock, flags);
961 	ap->ops->transmit_led_message(ap, led_message, 4);
962 }
963 
964 static void ahci_init_sw_activity(struct ata_link *link)
965 {
966 	struct ata_port *ap = link->ap;
967 	struct ahci_port_priv *pp = ap->private_data;
968 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
969 
970 	/* init activity stats, setup timer */
971 	emp->saved_activity = emp->activity = 0;
972 	setup_timer(&emp->timer, ahci_sw_activity_blink, (unsigned long)link);
973 
974 	/* check our blink policy and set flag for link if it's enabled */
975 	if (emp->blink_policy)
976 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
977 }
978 
979 int ahci_reset_em(struct ata_host *host)
980 {
981 	struct ahci_host_priv *hpriv = host->private_data;
982 	void __iomem *mmio = hpriv->mmio;
983 	u32 em_ctl;
984 
985 	em_ctl = readl(mmio + HOST_EM_CTL);
986 	if ((em_ctl & EM_CTL_TM) || (em_ctl & EM_CTL_RST))
987 		return -EINVAL;
988 
989 	writel(em_ctl | EM_CTL_RST, mmio + HOST_EM_CTL);
990 	return 0;
991 }
992 EXPORT_SYMBOL_GPL(ahci_reset_em);
993 
994 static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
995 					ssize_t size)
996 {
997 	struct ahci_host_priv *hpriv = ap->host->private_data;
998 	struct ahci_port_priv *pp = ap->private_data;
999 	void __iomem *mmio = hpriv->mmio;
1000 	u32 em_ctl;
1001 	u32 message[] = {0, 0};
1002 	unsigned long flags;
1003 	int pmp;
1004 	struct ahci_em_priv *emp;
1005 
1006 	/* get the slot number from the message */
1007 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
1008 	if (pmp < EM_MAX_SLOTS)
1009 		emp = &pp->em_priv[pmp];
1010 	else
1011 		return -EINVAL;
1012 
1013 	spin_lock_irqsave(ap->lock, flags);
1014 
1015 	/*
1016 	 * if we are still busy transmitting a previous message,
1017 	 * do not allow
1018 	 */
1019 	em_ctl = readl(mmio + HOST_EM_CTL);
1020 	if (em_ctl & EM_CTL_TM) {
1021 		spin_unlock_irqrestore(ap->lock, flags);
1022 		return -EBUSY;
1023 	}
1024 
1025 	if (hpriv->em_msg_type & EM_MSG_TYPE_LED) {
1026 		/*
1027 		 * create message header - this is all zero except for
1028 		 * the message size, which is 4 bytes.
1029 		 */
1030 		message[0] |= (4 << 8);
1031 
1032 		/* ignore 0:4 of byte zero, fill in port info yourself */
1033 		message[1] = ((state & ~EM_MSG_LED_HBA_PORT) | ap->port_no);
1034 
1035 		/* write message to EM_LOC */
1036 		writel(message[0], mmio + hpriv->em_loc);
1037 		writel(message[1], mmio + hpriv->em_loc+4);
1038 
1039 		/*
1040 		 * tell hardware to transmit the message
1041 		 */
1042 		writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
1043 	}
1044 
1045 	/* save off new led state for port/slot */
1046 	emp->led_state = state;
1047 
1048 	spin_unlock_irqrestore(ap->lock, flags);
1049 	return size;
1050 }
1051 
1052 static ssize_t ahci_led_show(struct ata_port *ap, char *buf)
1053 {
1054 	struct ahci_port_priv *pp = ap->private_data;
1055 	struct ata_link *link;
1056 	struct ahci_em_priv *emp;
1057 	int rc = 0;
1058 
1059 	ata_for_each_link(link, ap, EDGE) {
1060 		emp = &pp->em_priv[link->pmp];
1061 		rc += sprintf(buf, "%lx\n", emp->led_state);
1062 	}
1063 	return rc;
1064 }
1065 
1066 static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
1067 				size_t size)
1068 {
1069 	unsigned int state;
1070 	int pmp;
1071 	struct ahci_port_priv *pp = ap->private_data;
1072 	struct ahci_em_priv *emp;
1073 
1074 	if (kstrtouint(buf, 0, &state) < 0)
1075 		return -EINVAL;
1076 
1077 	/* get the slot number from the message */
1078 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
1079 	if (pmp < EM_MAX_SLOTS)
1080 		emp = &pp->em_priv[pmp];
1081 	else
1082 		return -EINVAL;
1083 
1084 	/* mask off the activity bits if we are in sw_activity
1085 	 * mode, user should turn off sw_activity before setting
1086 	 * activity led through em_message
1087 	 */
1088 	if (emp->blink_policy)
1089 		state &= ~EM_MSG_LED_VALUE_ACTIVITY;
1090 
1091 	return ap->ops->transmit_led_message(ap, state, size);
1092 }
1093 
1094 static ssize_t ahci_activity_store(struct ata_device *dev, enum sw_activity val)
1095 {
1096 	struct ata_link *link = dev->link;
1097 	struct ata_port *ap = link->ap;
1098 	struct ahci_port_priv *pp = ap->private_data;
1099 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1100 	u32 port_led_state = emp->led_state;
1101 
1102 	/* save the desired Activity LED behavior */
1103 	if (val == OFF) {
1104 		/* clear LFLAG */
1105 		link->flags &= ~(ATA_LFLAG_SW_ACTIVITY);
1106 
1107 		/* set the LED to OFF */
1108 		port_led_state &= EM_MSG_LED_VALUE_OFF;
1109 		port_led_state |= (ap->port_no | (link->pmp << 8));
1110 		ap->ops->transmit_led_message(ap, port_led_state, 4);
1111 	} else {
1112 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
1113 		if (val == BLINK_OFF) {
1114 			/* set LED to ON for idle */
1115 			port_led_state &= EM_MSG_LED_VALUE_OFF;
1116 			port_led_state |= (ap->port_no | (link->pmp << 8));
1117 			port_led_state |= EM_MSG_LED_VALUE_ON; /* check this */
1118 			ap->ops->transmit_led_message(ap, port_led_state, 4);
1119 		}
1120 	}
1121 	emp->blink_policy = val;
1122 	return 0;
1123 }
1124 
1125 static ssize_t ahci_activity_show(struct ata_device *dev, char *buf)
1126 {
1127 	struct ata_link *link = dev->link;
1128 	struct ata_port *ap = link->ap;
1129 	struct ahci_port_priv *pp = ap->private_data;
1130 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1131 
1132 	/* display the saved value of activity behavior for this
1133 	 * disk.
1134 	 */
1135 	return sprintf(buf, "%d\n", emp->blink_policy);
1136 }
1137 
1138 static void ahci_port_init(struct device *dev, struct ata_port *ap,
1139 			   int port_no, void __iomem *mmio,
1140 			   void __iomem *port_mmio)
1141 {
1142 	struct ahci_host_priv *hpriv = ap->host->private_data;
1143 	const char *emsg = NULL;
1144 	int rc;
1145 	u32 tmp;
1146 
1147 	/* make sure port is not active */
1148 	rc = ahci_deinit_port(ap, &emsg);
1149 	if (rc)
1150 		dev_warn(dev, "%s (%d)\n", emsg, rc);
1151 
1152 	/* clear SError */
1153 	tmp = readl(port_mmio + PORT_SCR_ERR);
1154 	VPRINTK("PORT_SCR_ERR 0x%x\n", tmp);
1155 	writel(tmp, port_mmio + PORT_SCR_ERR);
1156 
1157 	/* clear port IRQ */
1158 	tmp = readl(port_mmio + PORT_IRQ_STAT);
1159 	VPRINTK("PORT_IRQ_STAT 0x%x\n", tmp);
1160 	if (tmp)
1161 		writel(tmp, port_mmio + PORT_IRQ_STAT);
1162 
1163 	writel(1 << port_no, mmio + HOST_IRQ_STAT);
1164 
1165 	/* mark esata ports */
1166 	tmp = readl(port_mmio + PORT_CMD);
1167 	if ((tmp & PORT_CMD_HPCP) ||
1168 	    ((tmp & PORT_CMD_ESP) && (hpriv->cap & HOST_CAP_SXS)))
1169 		ap->pflags |= ATA_PFLAG_EXTERNAL;
1170 }
1171 
1172 void ahci_init_controller(struct ata_host *host)
1173 {
1174 	struct ahci_host_priv *hpriv = host->private_data;
1175 	void __iomem *mmio = hpriv->mmio;
1176 	int i;
1177 	void __iomem *port_mmio;
1178 	u32 tmp;
1179 
1180 	for (i = 0; i < host->n_ports; i++) {
1181 		struct ata_port *ap = host->ports[i];
1182 
1183 		port_mmio = ahci_port_base(ap);
1184 		if (ata_port_is_dummy(ap))
1185 			continue;
1186 
1187 		ahci_port_init(host->dev, ap, i, mmio, port_mmio);
1188 	}
1189 
1190 	tmp = readl(mmio + HOST_CTL);
1191 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1192 	writel(tmp | HOST_IRQ_EN, mmio + HOST_CTL);
1193 	tmp = readl(mmio + HOST_CTL);
1194 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1195 }
1196 EXPORT_SYMBOL_GPL(ahci_init_controller);
1197 
1198 static void ahci_dev_config(struct ata_device *dev)
1199 {
1200 	struct ahci_host_priv *hpriv = dev->link->ap->host->private_data;
1201 
1202 	if (hpriv->flags & AHCI_HFLAG_SECT255) {
1203 		dev->max_sectors = 255;
1204 		ata_dev_info(dev,
1205 			     "SB600 AHCI: limiting to 255 sectors per cmd\n");
1206 	}
1207 }
1208 
1209 unsigned int ahci_dev_classify(struct ata_port *ap)
1210 {
1211 	void __iomem *port_mmio = ahci_port_base(ap);
1212 	struct ata_taskfile tf;
1213 	u32 tmp;
1214 
1215 	tmp = readl(port_mmio + PORT_SIG);
1216 	tf.lbah		= (tmp >> 24)	& 0xff;
1217 	tf.lbam		= (tmp >> 16)	& 0xff;
1218 	tf.lbal		= (tmp >> 8)	& 0xff;
1219 	tf.nsect	= (tmp)		& 0xff;
1220 
1221 	return ata_dev_classify(&tf);
1222 }
1223 EXPORT_SYMBOL_GPL(ahci_dev_classify);
1224 
1225 void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
1226 			u32 opts)
1227 {
1228 	dma_addr_t cmd_tbl_dma;
1229 
1230 	cmd_tbl_dma = pp->cmd_tbl_dma + tag * AHCI_CMD_TBL_SZ;
1231 
1232 	pp->cmd_slot[tag].opts = cpu_to_le32(opts);
1233 	pp->cmd_slot[tag].status = 0;
1234 	pp->cmd_slot[tag].tbl_addr = cpu_to_le32(cmd_tbl_dma & 0xffffffff);
1235 	pp->cmd_slot[tag].tbl_addr_hi = cpu_to_le32((cmd_tbl_dma >> 16) >> 16);
1236 }
1237 EXPORT_SYMBOL_GPL(ahci_fill_cmd_slot);
1238 
1239 int ahci_kick_engine(struct ata_port *ap)
1240 {
1241 	void __iomem *port_mmio = ahci_port_base(ap);
1242 	struct ahci_host_priv *hpriv = ap->host->private_data;
1243 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1244 	u32 tmp;
1245 	int busy, rc;
1246 
1247 	/* stop engine */
1248 	rc = ahci_stop_engine(ap);
1249 	if (rc)
1250 		goto out_restart;
1251 
1252 	/* need to do CLO?
1253 	 * always do CLO if PMP is attached (AHCI-1.3 9.2)
1254 	 */
1255 	busy = status & (ATA_BUSY | ATA_DRQ);
1256 	if (!busy && !sata_pmp_attached(ap)) {
1257 		rc = 0;
1258 		goto out_restart;
1259 	}
1260 
1261 	if (!(hpriv->cap & HOST_CAP_CLO)) {
1262 		rc = -EOPNOTSUPP;
1263 		goto out_restart;
1264 	}
1265 
1266 	/* perform CLO */
1267 	tmp = readl(port_mmio + PORT_CMD);
1268 	tmp |= PORT_CMD_CLO;
1269 	writel(tmp, port_mmio + PORT_CMD);
1270 
1271 	rc = 0;
1272 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
1273 				PORT_CMD_CLO, PORT_CMD_CLO, 1, 500);
1274 	if (tmp & PORT_CMD_CLO)
1275 		rc = -EIO;
1276 
1277 	/* restart engine */
1278  out_restart:
1279 	hpriv->start_engine(ap);
1280 	return rc;
1281 }
1282 EXPORT_SYMBOL_GPL(ahci_kick_engine);
1283 
1284 static int ahci_exec_polled_cmd(struct ata_port *ap, int pmp,
1285 				struct ata_taskfile *tf, int is_cmd, u16 flags,
1286 				unsigned long timeout_msec)
1287 {
1288 	const u32 cmd_fis_len = 5; /* five dwords */
1289 	struct ahci_port_priv *pp = ap->private_data;
1290 	void __iomem *port_mmio = ahci_port_base(ap);
1291 	u8 *fis = pp->cmd_tbl;
1292 	u32 tmp;
1293 
1294 	/* prep the command */
1295 	ata_tf_to_fis(tf, pmp, is_cmd, fis);
1296 	ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12));
1297 
1298 	/* set port value for softreset of Port Multiplier */
1299 	if (pp->fbs_enabled && pp->fbs_last_dev != pmp) {
1300 		tmp = readl(port_mmio + PORT_FBS);
1301 		tmp &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC);
1302 		tmp |= pmp << PORT_FBS_DEV_OFFSET;
1303 		writel(tmp, port_mmio + PORT_FBS);
1304 		pp->fbs_last_dev = pmp;
1305 	}
1306 
1307 	/* issue & wait */
1308 	writel(1, port_mmio + PORT_CMD_ISSUE);
1309 
1310 	if (timeout_msec) {
1311 		tmp = ata_wait_register(ap, port_mmio + PORT_CMD_ISSUE,
1312 					0x1, 0x1, 1, timeout_msec);
1313 		if (tmp & 0x1) {
1314 			ahci_kick_engine(ap);
1315 			return -EBUSY;
1316 		}
1317 	} else
1318 		readl(port_mmio + PORT_CMD_ISSUE);	/* flush */
1319 
1320 	return 0;
1321 }
1322 
1323 int ahci_do_softreset(struct ata_link *link, unsigned int *class,
1324 		      int pmp, unsigned long deadline,
1325 		      int (*check_ready)(struct ata_link *link))
1326 {
1327 	struct ata_port *ap = link->ap;
1328 	struct ahci_host_priv *hpriv = ap->host->private_data;
1329 	struct ahci_port_priv *pp = ap->private_data;
1330 	const char *reason = NULL;
1331 	unsigned long now, msecs;
1332 	struct ata_taskfile tf;
1333 	bool fbs_disabled = false;
1334 	int rc;
1335 
1336 	DPRINTK("ENTER\n");
1337 
1338 	/* prepare for SRST (AHCI-1.1 10.4.1) */
1339 	rc = ahci_kick_engine(ap);
1340 	if (rc && rc != -EOPNOTSUPP)
1341 		ata_link_warn(link, "failed to reset engine (errno=%d)\n", rc);
1342 
1343 	/*
1344 	 * According to AHCI-1.2 9.3.9: if FBS is enable, software shall
1345 	 * clear PxFBS.EN to '0' prior to issuing software reset to devices
1346 	 * that is attached to port multiplier.
1347 	 */
1348 	if (!ata_is_host_link(link) && pp->fbs_enabled) {
1349 		ahci_disable_fbs(ap);
1350 		fbs_disabled = true;
1351 	}
1352 
1353 	ata_tf_init(link->device, &tf);
1354 
1355 	/* issue the first D2H Register FIS */
1356 	msecs = 0;
1357 	now = jiffies;
1358 	if (time_after(deadline, now))
1359 		msecs = jiffies_to_msecs(deadline - now);
1360 
1361 	tf.ctl |= ATA_SRST;
1362 	if (ahci_exec_polled_cmd(ap, pmp, &tf, 0,
1363 				 AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY, msecs)) {
1364 		rc = -EIO;
1365 		reason = "1st FIS failed";
1366 		goto fail;
1367 	}
1368 
1369 	/* spec says at least 5us, but be generous and sleep for 1ms */
1370 	ata_msleep(ap, 1);
1371 
1372 	/* issue the second D2H Register FIS */
1373 	tf.ctl &= ~ATA_SRST;
1374 	ahci_exec_polled_cmd(ap, pmp, &tf, 0, 0, 0);
1375 
1376 	/* wait for link to become ready */
1377 	rc = ata_wait_after_reset(link, deadline, check_ready);
1378 	if (rc == -EBUSY && hpriv->flags & AHCI_HFLAG_SRST_TOUT_IS_OFFLINE) {
1379 		/*
1380 		 * Workaround for cases where link online status can't
1381 		 * be trusted.  Treat device readiness timeout as link
1382 		 * offline.
1383 		 */
1384 		ata_link_info(link, "device not ready, treating as offline\n");
1385 		*class = ATA_DEV_NONE;
1386 	} else if (rc) {
1387 		/* link occupied, -ENODEV too is an error */
1388 		reason = "device not ready";
1389 		goto fail;
1390 	} else
1391 		*class = ahci_dev_classify(ap);
1392 
1393 	/* re-enable FBS if disabled before */
1394 	if (fbs_disabled)
1395 		ahci_enable_fbs(ap);
1396 
1397 	DPRINTK("EXIT, class=%u\n", *class);
1398 	return 0;
1399 
1400  fail:
1401 	ata_link_err(link, "softreset failed (%s)\n", reason);
1402 	return rc;
1403 }
1404 
1405 int ahci_check_ready(struct ata_link *link)
1406 {
1407 	void __iomem *port_mmio = ahci_port_base(link->ap);
1408 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1409 
1410 	return ata_check_ready(status);
1411 }
1412 EXPORT_SYMBOL_GPL(ahci_check_ready);
1413 
1414 static int ahci_softreset(struct ata_link *link, unsigned int *class,
1415 			  unsigned long deadline)
1416 {
1417 	int pmp = sata_srst_pmp(link);
1418 
1419 	DPRINTK("ENTER\n");
1420 
1421 	return ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
1422 }
1423 EXPORT_SYMBOL_GPL(ahci_do_softreset);
1424 
1425 static int ahci_bad_pmp_check_ready(struct ata_link *link)
1426 {
1427 	void __iomem *port_mmio = ahci_port_base(link->ap);
1428 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1429 	u32 irq_status = readl(port_mmio + PORT_IRQ_STAT);
1430 
1431 	/*
1432 	 * There is no need to check TFDATA if BAD PMP is found due to HW bug,
1433 	 * which can save timeout delay.
1434 	 */
1435 	if (irq_status & PORT_IRQ_BAD_PMP)
1436 		return -EIO;
1437 
1438 	return ata_check_ready(status);
1439 }
1440 
1441 static int ahci_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
1442 				    unsigned long deadline)
1443 {
1444 	struct ata_port *ap = link->ap;
1445 	void __iomem *port_mmio = ahci_port_base(ap);
1446 	int pmp = sata_srst_pmp(link);
1447 	int rc;
1448 	u32 irq_sts;
1449 
1450 	DPRINTK("ENTER\n");
1451 
1452 	rc = ahci_do_softreset(link, class, pmp, deadline,
1453 			       ahci_bad_pmp_check_ready);
1454 
1455 	/*
1456 	 * Soft reset fails with IPMS set when PMP is enabled but
1457 	 * SATA HDD/ODD is connected to SATA port, do soft reset
1458 	 * again to port 0.
1459 	 */
1460 	if (rc == -EIO) {
1461 		irq_sts = readl(port_mmio + PORT_IRQ_STAT);
1462 		if (irq_sts & PORT_IRQ_BAD_PMP) {
1463 			ata_link_warn(link,
1464 					"applying PMP SRST workaround "
1465 					"and retrying\n");
1466 			rc = ahci_do_softreset(link, class, 0, deadline,
1467 					       ahci_check_ready);
1468 		}
1469 	}
1470 
1471 	return rc;
1472 }
1473 
1474 static int ahci_hardreset(struct ata_link *link, unsigned int *class,
1475 			  unsigned long deadline)
1476 {
1477 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
1478 	struct ata_port *ap = link->ap;
1479 	struct ahci_port_priv *pp = ap->private_data;
1480 	struct ahci_host_priv *hpriv = ap->host->private_data;
1481 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
1482 	struct ata_taskfile tf;
1483 	bool online;
1484 	int rc;
1485 
1486 	DPRINTK("ENTER\n");
1487 
1488 	ahci_stop_engine(ap);
1489 
1490 	/* clear D2H reception area to properly wait for D2H FIS */
1491 	ata_tf_init(link->device, &tf);
1492 	tf.command = ATA_BUSY;
1493 	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
1494 
1495 	rc = sata_link_hardreset(link, timing, deadline, &online,
1496 				 ahci_check_ready);
1497 
1498 	hpriv->start_engine(ap);
1499 
1500 	if (online)
1501 		*class = ahci_dev_classify(ap);
1502 
1503 	DPRINTK("EXIT, rc=%d, class=%u\n", rc, *class);
1504 	return rc;
1505 }
1506 
1507 static void ahci_postreset(struct ata_link *link, unsigned int *class)
1508 {
1509 	struct ata_port *ap = link->ap;
1510 	void __iomem *port_mmio = ahci_port_base(ap);
1511 	u32 new_tmp, tmp;
1512 
1513 	ata_std_postreset(link, class);
1514 
1515 	/* Make sure port's ATAPI bit is set appropriately */
1516 	new_tmp = tmp = readl(port_mmio + PORT_CMD);
1517 	if (*class == ATA_DEV_ATAPI)
1518 		new_tmp |= PORT_CMD_ATAPI;
1519 	else
1520 		new_tmp &= ~PORT_CMD_ATAPI;
1521 	if (new_tmp != tmp) {
1522 		writel(new_tmp, port_mmio + PORT_CMD);
1523 		readl(port_mmio + PORT_CMD); /* flush */
1524 	}
1525 }
1526 
1527 static unsigned int ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl)
1528 {
1529 	struct scatterlist *sg;
1530 	struct ahci_sg *ahci_sg = cmd_tbl + AHCI_CMD_TBL_HDR_SZ;
1531 	unsigned int si;
1532 
1533 	VPRINTK("ENTER\n");
1534 
1535 	/*
1536 	 * Next, the S/G list.
1537 	 */
1538 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
1539 		dma_addr_t addr = sg_dma_address(sg);
1540 		u32 sg_len = sg_dma_len(sg);
1541 
1542 		ahci_sg[si].addr = cpu_to_le32(addr & 0xffffffff);
1543 		ahci_sg[si].addr_hi = cpu_to_le32((addr >> 16) >> 16);
1544 		ahci_sg[si].flags_size = cpu_to_le32(sg_len - 1);
1545 	}
1546 
1547 	return si;
1548 }
1549 
1550 static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc)
1551 {
1552 	struct ata_port *ap = qc->ap;
1553 	struct ahci_port_priv *pp = ap->private_data;
1554 
1555 	if (!sata_pmp_attached(ap) || pp->fbs_enabled)
1556 		return ata_std_qc_defer(qc);
1557 	else
1558 		return sata_pmp_qc_defer_cmd_switch(qc);
1559 }
1560 
1561 static void ahci_qc_prep(struct ata_queued_cmd *qc)
1562 {
1563 	struct ata_port *ap = qc->ap;
1564 	struct ahci_port_priv *pp = ap->private_data;
1565 	int is_atapi = ata_is_atapi(qc->tf.protocol);
1566 	void *cmd_tbl;
1567 	u32 opts;
1568 	const u32 cmd_fis_len = 5; /* five dwords */
1569 	unsigned int n_elem;
1570 
1571 	/*
1572 	 * Fill in command table information.  First, the header,
1573 	 * a SATA Register - Host to Device command FIS.
1574 	 */
1575 	cmd_tbl = pp->cmd_tbl + qc->tag * AHCI_CMD_TBL_SZ;
1576 
1577 	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, cmd_tbl);
1578 	if (is_atapi) {
1579 		memset(cmd_tbl + AHCI_CMD_TBL_CDB, 0, 32);
1580 		memcpy(cmd_tbl + AHCI_CMD_TBL_CDB, qc->cdb, qc->dev->cdb_len);
1581 	}
1582 
1583 	n_elem = 0;
1584 	if (qc->flags & ATA_QCFLAG_DMAMAP)
1585 		n_elem = ahci_fill_sg(qc, cmd_tbl);
1586 
1587 	/*
1588 	 * Fill in command slot information.
1589 	 */
1590 	opts = cmd_fis_len | n_elem << 16 | (qc->dev->link->pmp << 12);
1591 	if (qc->tf.flags & ATA_TFLAG_WRITE)
1592 		opts |= AHCI_CMD_WRITE;
1593 	if (is_atapi)
1594 		opts |= AHCI_CMD_ATAPI | AHCI_CMD_PREFETCH;
1595 
1596 	ahci_fill_cmd_slot(pp, qc->tag, opts);
1597 }
1598 
1599 static void ahci_fbs_dec_intr(struct ata_port *ap)
1600 {
1601 	struct ahci_port_priv *pp = ap->private_data;
1602 	void __iomem *port_mmio = ahci_port_base(ap);
1603 	u32 fbs = readl(port_mmio + PORT_FBS);
1604 	int retries = 3;
1605 
1606 	DPRINTK("ENTER\n");
1607 	BUG_ON(!pp->fbs_enabled);
1608 
1609 	/* time to wait for DEC is not specified by AHCI spec,
1610 	 * add a retry loop for safety.
1611 	 */
1612 	writel(fbs | PORT_FBS_DEC, port_mmio + PORT_FBS);
1613 	fbs = readl(port_mmio + PORT_FBS);
1614 	while ((fbs & PORT_FBS_DEC) && retries--) {
1615 		udelay(1);
1616 		fbs = readl(port_mmio + PORT_FBS);
1617 	}
1618 
1619 	if (fbs & PORT_FBS_DEC)
1620 		dev_err(ap->host->dev, "failed to clear device error\n");
1621 }
1622 
1623 static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
1624 {
1625 	struct ahci_host_priv *hpriv = ap->host->private_data;
1626 	struct ahci_port_priv *pp = ap->private_data;
1627 	struct ata_eh_info *host_ehi = &ap->link.eh_info;
1628 	struct ata_link *link = NULL;
1629 	struct ata_queued_cmd *active_qc;
1630 	struct ata_eh_info *active_ehi;
1631 	bool fbs_need_dec = false;
1632 	u32 serror;
1633 
1634 	/* determine active link with error */
1635 	if (pp->fbs_enabled) {
1636 		void __iomem *port_mmio = ahci_port_base(ap);
1637 		u32 fbs = readl(port_mmio + PORT_FBS);
1638 		int pmp = fbs >> PORT_FBS_DWE_OFFSET;
1639 
1640 		if ((fbs & PORT_FBS_SDE) && (pmp < ap->nr_pmp_links)) {
1641 			link = &ap->pmp_link[pmp];
1642 			fbs_need_dec = true;
1643 		}
1644 
1645 	} else
1646 		ata_for_each_link(link, ap, EDGE)
1647 			if (ata_link_active(link))
1648 				break;
1649 
1650 	if (!link)
1651 		link = &ap->link;
1652 
1653 	active_qc = ata_qc_from_tag(ap, link->active_tag);
1654 	active_ehi = &link->eh_info;
1655 
1656 	/* record irq stat */
1657 	ata_ehi_clear_desc(host_ehi);
1658 	ata_ehi_push_desc(host_ehi, "irq_stat 0x%08x", irq_stat);
1659 
1660 	/* AHCI needs SError cleared; otherwise, it might lock up */
1661 	ahci_scr_read(&ap->link, SCR_ERROR, &serror);
1662 	ahci_scr_write(&ap->link, SCR_ERROR, serror);
1663 	host_ehi->serror |= serror;
1664 
1665 	/* some controllers set IRQ_IF_ERR on device errors, ignore it */
1666 	if (hpriv->flags & AHCI_HFLAG_IGN_IRQ_IF_ERR)
1667 		irq_stat &= ~PORT_IRQ_IF_ERR;
1668 
1669 	if (irq_stat & PORT_IRQ_TF_ERR) {
1670 		/* If qc is active, charge it; otherwise, the active
1671 		 * link.  There's no active qc on NCQ errors.  It will
1672 		 * be determined by EH by reading log page 10h.
1673 		 */
1674 		if (active_qc)
1675 			active_qc->err_mask |= AC_ERR_DEV;
1676 		else
1677 			active_ehi->err_mask |= AC_ERR_DEV;
1678 
1679 		if (hpriv->flags & AHCI_HFLAG_IGN_SERR_INTERNAL)
1680 			host_ehi->serror &= ~SERR_INTERNAL;
1681 	}
1682 
1683 	if (irq_stat & PORT_IRQ_UNK_FIS) {
1684 		u32 *unk = pp->rx_fis + RX_FIS_UNK;
1685 
1686 		active_ehi->err_mask |= AC_ERR_HSM;
1687 		active_ehi->action |= ATA_EH_RESET;
1688 		ata_ehi_push_desc(active_ehi,
1689 				  "unknown FIS %08x %08x %08x %08x" ,
1690 				  unk[0], unk[1], unk[2], unk[3]);
1691 	}
1692 
1693 	if (sata_pmp_attached(ap) && (irq_stat & PORT_IRQ_BAD_PMP)) {
1694 		active_ehi->err_mask |= AC_ERR_HSM;
1695 		active_ehi->action |= ATA_EH_RESET;
1696 		ata_ehi_push_desc(active_ehi, "incorrect PMP");
1697 	}
1698 
1699 	if (irq_stat & (PORT_IRQ_HBUS_ERR | PORT_IRQ_HBUS_DATA_ERR)) {
1700 		host_ehi->err_mask |= AC_ERR_HOST_BUS;
1701 		host_ehi->action |= ATA_EH_RESET;
1702 		ata_ehi_push_desc(host_ehi, "host bus error");
1703 	}
1704 
1705 	if (irq_stat & PORT_IRQ_IF_ERR) {
1706 		if (fbs_need_dec)
1707 			active_ehi->err_mask |= AC_ERR_DEV;
1708 		else {
1709 			host_ehi->err_mask |= AC_ERR_ATA_BUS;
1710 			host_ehi->action |= ATA_EH_RESET;
1711 		}
1712 
1713 		ata_ehi_push_desc(host_ehi, "interface fatal error");
1714 	}
1715 
1716 	if (irq_stat & (PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)) {
1717 		ata_ehi_hotplugged(host_ehi);
1718 		ata_ehi_push_desc(host_ehi, "%s",
1719 			irq_stat & PORT_IRQ_CONNECT ?
1720 			"connection status changed" : "PHY RDY changed");
1721 	}
1722 
1723 	/* okay, let's hand over to EH */
1724 
1725 	if (irq_stat & PORT_IRQ_FREEZE)
1726 		ata_port_freeze(ap);
1727 	else if (fbs_need_dec) {
1728 		ata_link_abort(link);
1729 		ahci_fbs_dec_intr(ap);
1730 	} else
1731 		ata_port_abort(ap);
1732 }
1733 
1734 static void ahci_handle_port_interrupt(struct ata_port *ap,
1735 				       void __iomem *port_mmio, u32 status)
1736 {
1737 	struct ata_eh_info *ehi = &ap->link.eh_info;
1738 	struct ahci_port_priv *pp = ap->private_data;
1739 	struct ahci_host_priv *hpriv = ap->host->private_data;
1740 	int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
1741 	u32 qc_active = 0;
1742 	int rc;
1743 
1744 	/* ignore BAD_PMP while resetting */
1745 	if (unlikely(resetting))
1746 		status &= ~PORT_IRQ_BAD_PMP;
1747 
1748 	if (sata_lpm_ignore_phy_events(&ap->link)) {
1749 		status &= ~PORT_IRQ_PHYRDY;
1750 		ahci_scr_write(&ap->link, SCR_ERROR, SERR_PHYRDY_CHG);
1751 	}
1752 
1753 	if (unlikely(status & PORT_IRQ_ERROR)) {
1754 		ahci_error_intr(ap, status);
1755 		return;
1756 	}
1757 
1758 	if (status & PORT_IRQ_SDB_FIS) {
1759 		/* If SNotification is available, leave notification
1760 		 * handling to sata_async_notification().  If not,
1761 		 * emulate it by snooping SDB FIS RX area.
1762 		 *
1763 		 * Snooping FIS RX area is probably cheaper than
1764 		 * poking SNotification but some constrollers which
1765 		 * implement SNotification, ICH9 for example, don't
1766 		 * store AN SDB FIS into receive area.
1767 		 */
1768 		if (hpriv->cap & HOST_CAP_SNTF)
1769 			sata_async_notification(ap);
1770 		else {
1771 			/* If the 'N' bit in word 0 of the FIS is set,
1772 			 * we just received asynchronous notification.
1773 			 * Tell libata about it.
1774 			 *
1775 			 * Lack of SNotification should not appear in
1776 			 * ahci 1.2, so the workaround is unnecessary
1777 			 * when FBS is enabled.
1778 			 */
1779 			if (pp->fbs_enabled)
1780 				WARN_ON_ONCE(1);
1781 			else {
1782 				const __le32 *f = pp->rx_fis + RX_FIS_SDB;
1783 				u32 f0 = le32_to_cpu(f[0]);
1784 				if (f0 & (1 << 15))
1785 					sata_async_notification(ap);
1786 			}
1787 		}
1788 	}
1789 
1790 	/* pp->active_link is not reliable once FBS is enabled, both
1791 	 * PORT_SCR_ACT and PORT_CMD_ISSUE should be checked because
1792 	 * NCQ and non-NCQ commands may be in flight at the same time.
1793 	 */
1794 	if (pp->fbs_enabled) {
1795 		if (ap->qc_active) {
1796 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1797 			qc_active |= readl(port_mmio + PORT_CMD_ISSUE);
1798 		}
1799 	} else {
1800 		/* pp->active_link is valid iff any command is in flight */
1801 		if (ap->qc_active && pp->active_link->sactive)
1802 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1803 		else
1804 			qc_active = readl(port_mmio + PORT_CMD_ISSUE);
1805 	}
1806 
1807 
1808 	rc = ata_qc_complete_multiple(ap, qc_active);
1809 
1810 	/* while resetting, invalid completions are expected */
1811 	if (unlikely(rc < 0 && !resetting)) {
1812 		ehi->err_mask |= AC_ERR_HSM;
1813 		ehi->action |= ATA_EH_RESET;
1814 		ata_port_freeze(ap);
1815 	}
1816 }
1817 
1818 static void ahci_port_intr(struct ata_port *ap)
1819 {
1820 	void __iomem *port_mmio = ahci_port_base(ap);
1821 	u32 status;
1822 
1823 	status = readl(port_mmio + PORT_IRQ_STAT);
1824 	writel(status, port_mmio + PORT_IRQ_STAT);
1825 
1826 	ahci_handle_port_interrupt(ap, port_mmio, status);
1827 }
1828 
1829 static irqreturn_t ahci_multi_irqs_intr_hard(int irq, void *dev_instance)
1830 {
1831 	struct ata_port *ap = dev_instance;
1832 	void __iomem *port_mmio = ahci_port_base(ap);
1833 	u32 status;
1834 
1835 	VPRINTK("ENTER\n");
1836 
1837 	status = readl(port_mmio + PORT_IRQ_STAT);
1838 	writel(status, port_mmio + PORT_IRQ_STAT);
1839 
1840 	spin_lock(ap->lock);
1841 	ahci_handle_port_interrupt(ap, port_mmio, status);
1842 	spin_unlock(ap->lock);
1843 
1844 	VPRINTK("EXIT\n");
1845 
1846 	return IRQ_HANDLED;
1847 }
1848 
1849 static u32 ahci_handle_port_intr(struct ata_host *host, u32 irq_masked)
1850 {
1851 	unsigned int i, handled = 0;
1852 
1853 	for (i = 0; i < host->n_ports; i++) {
1854 		struct ata_port *ap;
1855 
1856 		if (!(irq_masked & (1 << i)))
1857 			continue;
1858 
1859 		ap = host->ports[i];
1860 		if (ap) {
1861 			ahci_port_intr(ap);
1862 			VPRINTK("port %u\n", i);
1863 		} else {
1864 			VPRINTK("port %u (no irq)\n", i);
1865 			if (ata_ratelimit())
1866 				dev_warn(host->dev,
1867 					 "interrupt on disabled port %u\n", i);
1868 		}
1869 
1870 		handled = 1;
1871 	}
1872 
1873 	return handled;
1874 }
1875 
1876 static irqreturn_t ahci_single_edge_irq_intr(int irq, void *dev_instance)
1877 {
1878 	struct ata_host *host = dev_instance;
1879 	struct ahci_host_priv *hpriv;
1880 	unsigned int rc = 0;
1881 	void __iomem *mmio;
1882 	u32 irq_stat, irq_masked;
1883 
1884 	VPRINTK("ENTER\n");
1885 
1886 	hpriv = host->private_data;
1887 	mmio = hpriv->mmio;
1888 
1889 	/* sigh.  0xffffffff is a valid return from h/w */
1890 	irq_stat = readl(mmio + HOST_IRQ_STAT);
1891 	if (!irq_stat)
1892 		return IRQ_NONE;
1893 
1894 	irq_masked = irq_stat & hpriv->port_map;
1895 
1896 	spin_lock(&host->lock);
1897 
1898 	/*
1899 	 * HOST_IRQ_STAT behaves as edge triggered latch meaning that
1900 	 * it should be cleared before all the port events are cleared.
1901 	 */
1902 	writel(irq_stat, mmio + HOST_IRQ_STAT);
1903 
1904 	rc = ahci_handle_port_intr(host, irq_masked);
1905 
1906 	spin_unlock(&host->lock);
1907 
1908 	VPRINTK("EXIT\n");
1909 
1910 	return IRQ_RETVAL(rc);
1911 }
1912 
1913 static irqreturn_t ahci_single_level_irq_intr(int irq, void *dev_instance)
1914 {
1915 	struct ata_host *host = dev_instance;
1916 	struct ahci_host_priv *hpriv;
1917 	unsigned int rc = 0;
1918 	void __iomem *mmio;
1919 	u32 irq_stat, irq_masked;
1920 
1921 	VPRINTK("ENTER\n");
1922 
1923 	hpriv = host->private_data;
1924 	mmio = hpriv->mmio;
1925 
1926 	/* sigh.  0xffffffff is a valid return from h/w */
1927 	irq_stat = readl(mmio + HOST_IRQ_STAT);
1928 	if (!irq_stat)
1929 		return IRQ_NONE;
1930 
1931 	irq_masked = irq_stat & hpriv->port_map;
1932 
1933 	spin_lock(&host->lock);
1934 
1935 	rc = ahci_handle_port_intr(host, irq_masked);
1936 
1937 	/* HOST_IRQ_STAT behaves as level triggered latch meaning that
1938 	 * it should be cleared after all the port events are cleared;
1939 	 * otherwise, it will raise a spurious interrupt after each
1940 	 * valid one.  Please read section 10.6.2 of ahci 1.1 for more
1941 	 * information.
1942 	 *
1943 	 * Also, use the unmasked value to clear interrupt as spurious
1944 	 * pending event on a dummy port might cause screaming IRQ.
1945 	 */
1946 	writel(irq_stat, mmio + HOST_IRQ_STAT);
1947 
1948 	spin_unlock(&host->lock);
1949 
1950 	VPRINTK("EXIT\n");
1951 
1952 	return IRQ_RETVAL(rc);
1953 }
1954 
1955 unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
1956 {
1957 	struct ata_port *ap = qc->ap;
1958 	void __iomem *port_mmio = ahci_port_base(ap);
1959 	struct ahci_port_priv *pp = ap->private_data;
1960 
1961 	/* Keep track of the currently active link.  It will be used
1962 	 * in completion path to determine whether NCQ phase is in
1963 	 * progress.
1964 	 */
1965 	pp->active_link = qc->dev->link;
1966 
1967 	if (qc->tf.protocol == ATA_PROT_NCQ)
1968 		writel(1 << qc->tag, port_mmio + PORT_SCR_ACT);
1969 
1970 	if (pp->fbs_enabled && pp->fbs_last_dev != qc->dev->link->pmp) {
1971 		u32 fbs = readl(port_mmio + PORT_FBS);
1972 		fbs &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC);
1973 		fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
1974 		writel(fbs, port_mmio + PORT_FBS);
1975 		pp->fbs_last_dev = qc->dev->link->pmp;
1976 	}
1977 
1978 	writel(1 << qc->tag, port_mmio + PORT_CMD_ISSUE);
1979 
1980 	ahci_sw_activity(qc->dev->link);
1981 
1982 	return 0;
1983 }
1984 EXPORT_SYMBOL_GPL(ahci_qc_issue);
1985 
1986 static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
1987 {
1988 	struct ahci_port_priv *pp = qc->ap->private_data;
1989 	u8 *rx_fis = pp->rx_fis;
1990 
1991 	if (pp->fbs_enabled)
1992 		rx_fis += qc->dev->link->pmp * AHCI_RX_FIS_SZ;
1993 
1994 	/*
1995 	 * After a successful execution of an ATA PIO data-in command,
1996 	 * the device doesn't send D2H Reg FIS to update the TF and
1997 	 * the host should take TF and E_Status from the preceding PIO
1998 	 * Setup FIS.
1999 	 */
2000 	if (qc->tf.protocol == ATA_PROT_PIO && qc->dma_dir == DMA_FROM_DEVICE &&
2001 	    !(qc->flags & ATA_QCFLAG_FAILED)) {
2002 		ata_tf_from_fis(rx_fis + RX_FIS_PIO_SETUP, &qc->result_tf);
2003 		qc->result_tf.command = (rx_fis + RX_FIS_PIO_SETUP)[15];
2004 	} else
2005 		ata_tf_from_fis(rx_fis + RX_FIS_D2H_REG, &qc->result_tf);
2006 
2007 	return true;
2008 }
2009 
2010 static void ahci_freeze(struct ata_port *ap)
2011 {
2012 	void __iomem *port_mmio = ahci_port_base(ap);
2013 
2014 	/* turn IRQ off */
2015 	writel(0, port_mmio + PORT_IRQ_MASK);
2016 }
2017 
2018 static void ahci_thaw(struct ata_port *ap)
2019 {
2020 	struct ahci_host_priv *hpriv = ap->host->private_data;
2021 	void __iomem *mmio = hpriv->mmio;
2022 	void __iomem *port_mmio = ahci_port_base(ap);
2023 	u32 tmp;
2024 	struct ahci_port_priv *pp = ap->private_data;
2025 
2026 	/* clear IRQ */
2027 	tmp = readl(port_mmio + PORT_IRQ_STAT);
2028 	writel(tmp, port_mmio + PORT_IRQ_STAT);
2029 	writel(1 << ap->port_no, mmio + HOST_IRQ_STAT);
2030 
2031 	/* turn IRQ back on */
2032 	writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
2033 }
2034 
2035 void ahci_error_handler(struct ata_port *ap)
2036 {
2037 	struct ahci_host_priv *hpriv = ap->host->private_data;
2038 
2039 	if (!(ap->pflags & ATA_PFLAG_FROZEN)) {
2040 		/* restart engine */
2041 		ahci_stop_engine(ap);
2042 		hpriv->start_engine(ap);
2043 	}
2044 
2045 	sata_pmp_error_handler(ap);
2046 
2047 	if (!ata_dev_enabled(ap->link.device))
2048 		ahci_stop_engine(ap);
2049 }
2050 EXPORT_SYMBOL_GPL(ahci_error_handler);
2051 
2052 static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
2053 {
2054 	struct ata_port *ap = qc->ap;
2055 
2056 	/* make DMA engine forget about the failed command */
2057 	if (qc->flags & ATA_QCFLAG_FAILED)
2058 		ahci_kick_engine(ap);
2059 }
2060 
2061 static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep)
2062 {
2063 	struct ahci_host_priv *hpriv = ap->host->private_data;
2064 	void __iomem *port_mmio = ahci_port_base(ap);
2065 	struct ata_device *dev = ap->link.device;
2066 	u32 devslp, dm, dito, mdat, deto;
2067 	int rc;
2068 	unsigned int err_mask;
2069 
2070 	devslp = readl(port_mmio + PORT_DEVSLP);
2071 	if (!(devslp & PORT_DEVSLP_DSP)) {
2072 		dev_info(ap->host->dev, "port does not support device sleep\n");
2073 		return;
2074 	}
2075 
2076 	/* disable device sleep */
2077 	if (!sleep) {
2078 		if (devslp & PORT_DEVSLP_ADSE) {
2079 			writel(devslp & ~PORT_DEVSLP_ADSE,
2080 			       port_mmio + PORT_DEVSLP);
2081 			err_mask = ata_dev_set_feature(dev,
2082 						       SETFEATURES_SATA_DISABLE,
2083 						       SATA_DEVSLP);
2084 			if (err_mask && err_mask != AC_ERR_DEV)
2085 				ata_dev_warn(dev, "failed to disable DEVSLP\n");
2086 		}
2087 		return;
2088 	}
2089 
2090 	/* device sleep was already enabled */
2091 	if (devslp & PORT_DEVSLP_ADSE)
2092 		return;
2093 
2094 	/* set DITO, MDAT, DETO and enable DevSlp, need to stop engine first */
2095 	rc = ahci_stop_engine(ap);
2096 	if (rc)
2097 		return;
2098 
2099 	dm = (devslp & PORT_DEVSLP_DM_MASK) >> PORT_DEVSLP_DM_OFFSET;
2100 	dito = devslp_idle_timeout / (dm + 1);
2101 	if (dito > 0x3ff)
2102 		dito = 0x3ff;
2103 
2104 	/* Use the nominal value 10 ms if the read MDAT is zero,
2105 	 * the nominal value of DETO is 20 ms.
2106 	 */
2107 	if (dev->devslp_timing[ATA_LOG_DEVSLP_VALID] &
2108 	    ATA_LOG_DEVSLP_VALID_MASK) {
2109 		mdat = dev->devslp_timing[ATA_LOG_DEVSLP_MDAT] &
2110 		       ATA_LOG_DEVSLP_MDAT_MASK;
2111 		if (!mdat)
2112 			mdat = 10;
2113 		deto = dev->devslp_timing[ATA_LOG_DEVSLP_DETO];
2114 		if (!deto)
2115 			deto = 20;
2116 	} else {
2117 		mdat = 10;
2118 		deto = 20;
2119 	}
2120 
2121 	devslp |= ((dito << PORT_DEVSLP_DITO_OFFSET) |
2122 		   (mdat << PORT_DEVSLP_MDAT_OFFSET) |
2123 		   (deto << PORT_DEVSLP_DETO_OFFSET) |
2124 		   PORT_DEVSLP_ADSE);
2125 	writel(devslp, port_mmio + PORT_DEVSLP);
2126 
2127 	hpriv->start_engine(ap);
2128 
2129 	/* enable device sleep feature for the drive */
2130 	err_mask = ata_dev_set_feature(dev,
2131 				       SETFEATURES_SATA_ENABLE,
2132 				       SATA_DEVSLP);
2133 	if (err_mask && err_mask != AC_ERR_DEV)
2134 		ata_dev_warn(dev, "failed to enable DEVSLP\n");
2135 }
2136 
2137 static void ahci_enable_fbs(struct ata_port *ap)
2138 {
2139 	struct ahci_host_priv *hpriv = ap->host->private_data;
2140 	struct ahci_port_priv *pp = ap->private_data;
2141 	void __iomem *port_mmio = ahci_port_base(ap);
2142 	u32 fbs;
2143 	int rc;
2144 
2145 	if (!pp->fbs_supported)
2146 		return;
2147 
2148 	fbs = readl(port_mmio + PORT_FBS);
2149 	if (fbs & PORT_FBS_EN) {
2150 		pp->fbs_enabled = true;
2151 		pp->fbs_last_dev = -1; /* initialization */
2152 		return;
2153 	}
2154 
2155 	rc = ahci_stop_engine(ap);
2156 	if (rc)
2157 		return;
2158 
2159 	writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
2160 	fbs = readl(port_mmio + PORT_FBS);
2161 	if (fbs & PORT_FBS_EN) {
2162 		dev_info(ap->host->dev, "FBS is enabled\n");
2163 		pp->fbs_enabled = true;
2164 		pp->fbs_last_dev = -1; /* initialization */
2165 	} else
2166 		dev_err(ap->host->dev, "Failed to enable FBS\n");
2167 
2168 	hpriv->start_engine(ap);
2169 }
2170 
2171 static void ahci_disable_fbs(struct ata_port *ap)
2172 {
2173 	struct ahci_host_priv *hpriv = ap->host->private_data;
2174 	struct ahci_port_priv *pp = ap->private_data;
2175 	void __iomem *port_mmio = ahci_port_base(ap);
2176 	u32 fbs;
2177 	int rc;
2178 
2179 	if (!pp->fbs_supported)
2180 		return;
2181 
2182 	fbs = readl(port_mmio + PORT_FBS);
2183 	if ((fbs & PORT_FBS_EN) == 0) {
2184 		pp->fbs_enabled = false;
2185 		return;
2186 	}
2187 
2188 	rc = ahci_stop_engine(ap);
2189 	if (rc)
2190 		return;
2191 
2192 	writel(fbs & ~PORT_FBS_EN, port_mmio + PORT_FBS);
2193 	fbs = readl(port_mmio + PORT_FBS);
2194 	if (fbs & PORT_FBS_EN)
2195 		dev_err(ap->host->dev, "Failed to disable FBS\n");
2196 	else {
2197 		dev_info(ap->host->dev, "FBS is disabled\n");
2198 		pp->fbs_enabled = false;
2199 	}
2200 
2201 	hpriv->start_engine(ap);
2202 }
2203 
2204 static void ahci_pmp_attach(struct ata_port *ap)
2205 {
2206 	void __iomem *port_mmio = ahci_port_base(ap);
2207 	struct ahci_port_priv *pp = ap->private_data;
2208 	u32 cmd;
2209 
2210 	cmd = readl(port_mmio + PORT_CMD);
2211 	cmd |= PORT_CMD_PMP;
2212 	writel(cmd, port_mmio + PORT_CMD);
2213 
2214 	ahci_enable_fbs(ap);
2215 
2216 	pp->intr_mask |= PORT_IRQ_BAD_PMP;
2217 
2218 	/*
2219 	 * We must not change the port interrupt mask register if the
2220 	 * port is marked frozen, the value in pp->intr_mask will be
2221 	 * restored later when the port is thawed.
2222 	 *
2223 	 * Note that during initialization, the port is marked as
2224 	 * frozen since the irq handler is not yet registered.
2225 	 */
2226 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
2227 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
2228 }
2229 
2230 static void ahci_pmp_detach(struct ata_port *ap)
2231 {
2232 	void __iomem *port_mmio = ahci_port_base(ap);
2233 	struct ahci_port_priv *pp = ap->private_data;
2234 	u32 cmd;
2235 
2236 	ahci_disable_fbs(ap);
2237 
2238 	cmd = readl(port_mmio + PORT_CMD);
2239 	cmd &= ~PORT_CMD_PMP;
2240 	writel(cmd, port_mmio + PORT_CMD);
2241 
2242 	pp->intr_mask &= ~PORT_IRQ_BAD_PMP;
2243 
2244 	/* see comment above in ahci_pmp_attach() */
2245 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
2246 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
2247 }
2248 
2249 int ahci_port_resume(struct ata_port *ap)
2250 {
2251 	ahci_power_up(ap);
2252 	ahci_start_port(ap);
2253 
2254 	if (sata_pmp_attached(ap))
2255 		ahci_pmp_attach(ap);
2256 	else
2257 		ahci_pmp_detach(ap);
2258 
2259 	return 0;
2260 }
2261 EXPORT_SYMBOL_GPL(ahci_port_resume);
2262 
2263 #ifdef CONFIG_PM
2264 static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg)
2265 {
2266 	const char *emsg = NULL;
2267 	int rc;
2268 
2269 	rc = ahci_deinit_port(ap, &emsg);
2270 	if (rc == 0)
2271 		ahci_power_down(ap);
2272 	else {
2273 		ata_port_err(ap, "%s (%d)\n", emsg, rc);
2274 		ata_port_freeze(ap);
2275 	}
2276 
2277 	return rc;
2278 }
2279 #endif
2280 
2281 static int ahci_port_start(struct ata_port *ap)
2282 {
2283 	struct ahci_host_priv *hpriv = ap->host->private_data;
2284 	struct device *dev = ap->host->dev;
2285 	struct ahci_port_priv *pp;
2286 	void *mem;
2287 	dma_addr_t mem_dma;
2288 	size_t dma_sz, rx_fis_sz;
2289 
2290 	pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
2291 	if (!pp)
2292 		return -ENOMEM;
2293 
2294 	if (ap->host->n_ports > 1) {
2295 		pp->irq_desc = devm_kzalloc(dev, 8, GFP_KERNEL);
2296 		if (!pp->irq_desc) {
2297 			devm_kfree(dev, pp);
2298 			return -ENOMEM;
2299 		}
2300 		snprintf(pp->irq_desc, 8,
2301 			 "%s%d", dev_driver_string(dev), ap->port_no);
2302 	}
2303 
2304 	/* check FBS capability */
2305 	if ((hpriv->cap & HOST_CAP_FBS) && sata_pmp_supported(ap)) {
2306 		void __iomem *port_mmio = ahci_port_base(ap);
2307 		u32 cmd = readl(port_mmio + PORT_CMD);
2308 		if (cmd & PORT_CMD_FBSCP)
2309 			pp->fbs_supported = true;
2310 		else if (hpriv->flags & AHCI_HFLAG_YES_FBS) {
2311 			dev_info(dev, "port %d can do FBS, forcing FBSCP\n",
2312 				 ap->port_no);
2313 			pp->fbs_supported = true;
2314 		} else
2315 			dev_warn(dev, "port %d is not capable of FBS\n",
2316 				 ap->port_no);
2317 	}
2318 
2319 	if (pp->fbs_supported) {
2320 		dma_sz = AHCI_PORT_PRIV_FBS_DMA_SZ;
2321 		rx_fis_sz = AHCI_RX_FIS_SZ * 16;
2322 	} else {
2323 		dma_sz = AHCI_PORT_PRIV_DMA_SZ;
2324 		rx_fis_sz = AHCI_RX_FIS_SZ;
2325 	}
2326 
2327 	mem = dmam_alloc_coherent(dev, dma_sz, &mem_dma, GFP_KERNEL);
2328 	if (!mem)
2329 		return -ENOMEM;
2330 	memset(mem, 0, dma_sz);
2331 
2332 	/*
2333 	 * First item in chunk of DMA memory: 32-slot command table,
2334 	 * 32 bytes each in size
2335 	 */
2336 	pp->cmd_slot = mem;
2337 	pp->cmd_slot_dma = mem_dma;
2338 
2339 	mem += AHCI_CMD_SLOT_SZ;
2340 	mem_dma += AHCI_CMD_SLOT_SZ;
2341 
2342 	/*
2343 	 * Second item: Received-FIS area
2344 	 */
2345 	pp->rx_fis = mem;
2346 	pp->rx_fis_dma = mem_dma;
2347 
2348 	mem += rx_fis_sz;
2349 	mem_dma += rx_fis_sz;
2350 
2351 	/*
2352 	 * Third item: data area for storing a single command
2353 	 * and its scatter-gather table
2354 	 */
2355 	pp->cmd_tbl = mem;
2356 	pp->cmd_tbl_dma = mem_dma;
2357 
2358 	/*
2359 	 * Save off initial list of interrupts to be enabled.
2360 	 * This could be changed later
2361 	 */
2362 	pp->intr_mask = DEF_PORT_IRQ;
2363 
2364 	/*
2365 	 * Switch to per-port locking in case each port has its own MSI vector.
2366 	 */
2367 	if (hpriv->flags & AHCI_HFLAG_MULTI_MSI) {
2368 		spin_lock_init(&pp->lock);
2369 		ap->lock = &pp->lock;
2370 	}
2371 
2372 	ap->private_data = pp;
2373 
2374 	/* engage engines, captain */
2375 	return ahci_port_resume(ap);
2376 }
2377 
2378 static void ahci_port_stop(struct ata_port *ap)
2379 {
2380 	const char *emsg = NULL;
2381 	int rc;
2382 
2383 	/* de-initialize port */
2384 	rc = ahci_deinit_port(ap, &emsg);
2385 	if (rc)
2386 		ata_port_warn(ap, "%s (%d)\n", emsg, rc);
2387 }
2388 
2389 void ahci_print_info(struct ata_host *host, const char *scc_s)
2390 {
2391 	struct ahci_host_priv *hpriv = host->private_data;
2392 	void __iomem *mmio = hpriv->mmio;
2393 	u32 vers, cap, cap2, impl, speed;
2394 	const char *speed_s;
2395 
2396 	vers = readl(mmio + HOST_VERSION);
2397 	cap = hpriv->cap;
2398 	cap2 = hpriv->cap2;
2399 	impl = hpriv->port_map;
2400 
2401 	speed = (cap >> 20) & 0xf;
2402 	if (speed == 1)
2403 		speed_s = "1.5";
2404 	else if (speed == 2)
2405 		speed_s = "3";
2406 	else if (speed == 3)
2407 		speed_s = "6";
2408 	else
2409 		speed_s = "?";
2410 
2411 	dev_info(host->dev,
2412 		"AHCI %02x%02x.%02x%02x "
2413 		"%u slots %u ports %s Gbps 0x%x impl %s mode\n"
2414 		,
2415 
2416 		(vers >> 24) & 0xff,
2417 		(vers >> 16) & 0xff,
2418 		(vers >> 8) & 0xff,
2419 		vers & 0xff,
2420 
2421 		((cap >> 8) & 0x1f) + 1,
2422 		(cap & 0x1f) + 1,
2423 		speed_s,
2424 		impl,
2425 		scc_s);
2426 
2427 	dev_info(host->dev,
2428 		"flags: "
2429 		"%s%s%s%s%s%s%s"
2430 		"%s%s%s%s%s%s%s"
2431 		"%s%s%s%s%s%s%s"
2432 		"%s%s\n"
2433 		,
2434 
2435 		cap & HOST_CAP_64 ? "64bit " : "",
2436 		cap & HOST_CAP_NCQ ? "ncq " : "",
2437 		cap & HOST_CAP_SNTF ? "sntf " : "",
2438 		cap & HOST_CAP_MPS ? "ilck " : "",
2439 		cap & HOST_CAP_SSS ? "stag " : "",
2440 		cap & HOST_CAP_ALPM ? "pm " : "",
2441 		cap & HOST_CAP_LED ? "led " : "",
2442 		cap & HOST_CAP_CLO ? "clo " : "",
2443 		cap & HOST_CAP_ONLY ? "only " : "",
2444 		cap & HOST_CAP_PMP ? "pmp " : "",
2445 		cap & HOST_CAP_FBS ? "fbs " : "",
2446 		cap & HOST_CAP_PIO_MULTI ? "pio " : "",
2447 		cap & HOST_CAP_SSC ? "slum " : "",
2448 		cap & HOST_CAP_PART ? "part " : "",
2449 		cap & HOST_CAP_CCC ? "ccc " : "",
2450 		cap & HOST_CAP_EMS ? "ems " : "",
2451 		cap & HOST_CAP_SXS ? "sxs " : "",
2452 		cap2 & HOST_CAP2_DESO ? "deso " : "",
2453 		cap2 & HOST_CAP2_SADM ? "sadm " : "",
2454 		cap2 & HOST_CAP2_SDS ? "sds " : "",
2455 		cap2 & HOST_CAP2_APST ? "apst " : "",
2456 		cap2 & HOST_CAP2_NVMHCI ? "nvmp " : "",
2457 		cap2 & HOST_CAP2_BOH ? "boh " : ""
2458 		);
2459 }
2460 EXPORT_SYMBOL_GPL(ahci_print_info);
2461 
2462 void ahci_set_em_messages(struct ahci_host_priv *hpriv,
2463 			  struct ata_port_info *pi)
2464 {
2465 	u8 messages;
2466 	void __iomem *mmio = hpriv->mmio;
2467 	u32 em_loc = readl(mmio + HOST_EM_LOC);
2468 	u32 em_ctl = readl(mmio + HOST_EM_CTL);
2469 
2470 	if (!ahci_em_messages || !(hpriv->cap & HOST_CAP_EMS))
2471 		return;
2472 
2473 	messages = (em_ctl & EM_CTRL_MSG_TYPE) >> 16;
2474 
2475 	if (messages) {
2476 		/* store em_loc */
2477 		hpriv->em_loc = ((em_loc >> 16) * 4);
2478 		hpriv->em_buf_sz = ((em_loc & 0xff) * 4);
2479 		hpriv->em_msg_type = messages;
2480 		pi->flags |= ATA_FLAG_EM;
2481 		if (!(em_ctl & EM_CTL_ALHD))
2482 			pi->flags |= ATA_FLAG_SW_ACTIVITY;
2483 	}
2484 }
2485 EXPORT_SYMBOL_GPL(ahci_set_em_messages);
2486 
2487 static int ahci_host_activate_multi_irqs(struct ata_host *host,
2488 					 struct scsi_host_template *sht)
2489 {
2490 	struct ahci_host_priv *hpriv = host->private_data;
2491 	int i, rc;
2492 
2493 	rc = ata_host_start(host);
2494 	if (rc)
2495 		return rc;
2496 	/*
2497 	 * Requests IRQs according to AHCI-1.1 when multiple MSIs were
2498 	 * allocated. That is one MSI per port, starting from @irq.
2499 	 */
2500 	for (i = 0; i < host->n_ports; i++) {
2501 		struct ahci_port_priv *pp = host->ports[i]->private_data;
2502 		int irq = ahci_irq_vector(hpriv, i);
2503 
2504 		/* Do not receive interrupts sent by dummy ports */
2505 		if (!pp) {
2506 			disable_irq(irq + i);
2507 			continue;
2508 		}
2509 
2510 		rc = devm_request_irq(host->dev, irq, ahci_multi_irqs_intr_hard,
2511 				0, pp->irq_desc, host->ports[i]);
2512 
2513 		if (rc)
2514 			return rc;
2515 		ata_port_desc(host->ports[i], "irq %d", irq);
2516 	}
2517 
2518 	return ata_host_register(host, sht);
2519 }
2520 
2521 /**
2522  *	ahci_host_activate - start AHCI host, request IRQs and register it
2523  *	@host: target ATA host
2524  *	@sht: scsi_host_template to use when registering the host
2525  *
2526  *	LOCKING:
2527  *	Inherited from calling layer (may sleep).
2528  *
2529  *	RETURNS:
2530  *	0 on success, -errno otherwise.
2531  */
2532 int ahci_host_activate(struct ata_host *host, struct scsi_host_template *sht)
2533 {
2534 	struct ahci_host_priv *hpriv = host->private_data;
2535 	int irq = hpriv->irq;
2536 	int rc;
2537 
2538 	if (hpriv->flags & (AHCI_HFLAG_MULTI_MSI | AHCI_HFLAG_MULTI_MSIX))
2539 		rc = ahci_host_activate_multi_irqs(host, sht);
2540 	else if (hpriv->flags & AHCI_HFLAG_EDGE_IRQ)
2541 		rc = ata_host_activate(host, irq, ahci_single_edge_irq_intr,
2542 				       IRQF_SHARED, sht);
2543 	else
2544 		rc = ata_host_activate(host, irq, ahci_single_level_irq_intr,
2545 				       IRQF_SHARED, sht);
2546 	return rc;
2547 }
2548 EXPORT_SYMBOL_GPL(ahci_host_activate);
2549 
2550 MODULE_AUTHOR("Jeff Garzik");
2551 MODULE_DESCRIPTION("Common AHCI SATA low-level routines");
2552 MODULE_LICENSE("GPL");
2553