xref: /openbmc/linux/drivers/ata/libahci.c (revision 63dc02bd)
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_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
86 			  unsigned long deadline);
87 static int ahci_hardreset(struct ata_link *link, unsigned int *class,
88 			  unsigned long deadline);
89 static void ahci_postreset(struct ata_link *link, unsigned int *class);
90 static void ahci_error_handler(struct ata_port *ap);
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 #ifdef CONFIG_PM
175 	.port_suspend		= ahci_port_suspend,
176 	.port_resume		= ahci_port_resume,
177 #endif
178 	.port_start		= ahci_port_start,
179 	.port_stop		= ahci_port_stop,
180 };
181 EXPORT_SYMBOL_GPL(ahci_ops);
182 
183 struct ata_port_operations ahci_pmp_retry_srst_ops = {
184 	.inherits		= &ahci_ops,
185 	.softreset		= ahci_pmp_retry_softreset,
186 };
187 EXPORT_SYMBOL_GPL(ahci_pmp_retry_srst_ops);
188 
189 int ahci_em_messages = 1;
190 EXPORT_SYMBOL_GPL(ahci_em_messages);
191 module_param(ahci_em_messages, int, 0444);
192 /* add other LED protocol types when they become supported */
193 MODULE_PARM_DESC(ahci_em_messages,
194 	"AHCI Enclosure Management Message control (0 = off, 1 = on)");
195 
196 static void ahci_enable_ahci(void __iomem *mmio)
197 {
198 	int i;
199 	u32 tmp;
200 
201 	/* turn on AHCI_EN */
202 	tmp = readl(mmio + HOST_CTL);
203 	if (tmp & HOST_AHCI_EN)
204 		return;
205 
206 	/* Some controllers need AHCI_EN to be written multiple times.
207 	 * Try a few times before giving up.
208 	 */
209 	for (i = 0; i < 5; i++) {
210 		tmp |= HOST_AHCI_EN;
211 		writel(tmp, mmio + HOST_CTL);
212 		tmp = readl(mmio + HOST_CTL);	/* flush && sanity check */
213 		if (tmp & HOST_AHCI_EN)
214 			return;
215 		msleep(10);
216 	}
217 
218 	WARN_ON(1);
219 }
220 
221 static ssize_t ahci_show_host_caps(struct device *dev,
222 				   struct device_attribute *attr, char *buf)
223 {
224 	struct Scsi_Host *shost = class_to_shost(dev);
225 	struct ata_port *ap = ata_shost_to_port(shost);
226 	struct ahci_host_priv *hpriv = ap->host->private_data;
227 
228 	return sprintf(buf, "%x\n", hpriv->cap);
229 }
230 
231 static ssize_t ahci_show_host_cap2(struct device *dev,
232 				   struct device_attribute *attr, char *buf)
233 {
234 	struct Scsi_Host *shost = class_to_shost(dev);
235 	struct ata_port *ap = ata_shost_to_port(shost);
236 	struct ahci_host_priv *hpriv = ap->host->private_data;
237 
238 	return sprintf(buf, "%x\n", hpriv->cap2);
239 }
240 
241 static ssize_t ahci_show_host_version(struct device *dev,
242 				   struct device_attribute *attr, char *buf)
243 {
244 	struct Scsi_Host *shost = class_to_shost(dev);
245 	struct ata_port *ap = ata_shost_to_port(shost);
246 	struct ahci_host_priv *hpriv = ap->host->private_data;
247 	void __iomem *mmio = hpriv->mmio;
248 
249 	return sprintf(buf, "%x\n", readl(mmio + HOST_VERSION));
250 }
251 
252 static ssize_t ahci_show_port_cmd(struct device *dev,
253 				  struct device_attribute *attr, char *buf)
254 {
255 	struct Scsi_Host *shost = class_to_shost(dev);
256 	struct ata_port *ap = ata_shost_to_port(shost);
257 	void __iomem *port_mmio = ahci_port_base(ap);
258 
259 	return sprintf(buf, "%x\n", readl(port_mmio + PORT_CMD));
260 }
261 
262 static ssize_t ahci_read_em_buffer(struct device *dev,
263 				   struct device_attribute *attr, char *buf)
264 {
265 	struct Scsi_Host *shost = class_to_shost(dev);
266 	struct ata_port *ap = ata_shost_to_port(shost);
267 	struct ahci_host_priv *hpriv = ap->host->private_data;
268 	void __iomem *mmio = hpriv->mmio;
269 	void __iomem *em_mmio = mmio + hpriv->em_loc;
270 	u32 em_ctl, msg;
271 	unsigned long flags;
272 	size_t count;
273 	int i;
274 
275 	spin_lock_irqsave(ap->lock, flags);
276 
277 	em_ctl = readl(mmio + HOST_EM_CTL);
278 	if (!(ap->flags & ATA_FLAG_EM) || em_ctl & EM_CTL_XMT ||
279 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO)) {
280 		spin_unlock_irqrestore(ap->lock, flags);
281 		return -EINVAL;
282 	}
283 
284 	if (!(em_ctl & EM_CTL_MR)) {
285 		spin_unlock_irqrestore(ap->lock, flags);
286 		return -EAGAIN;
287 	}
288 
289 	if (!(em_ctl & EM_CTL_SMB))
290 		em_mmio += hpriv->em_buf_sz;
291 
292 	count = hpriv->em_buf_sz;
293 
294 	/* the count should not be larger than PAGE_SIZE */
295 	if (count > PAGE_SIZE) {
296 		if (printk_ratelimit())
297 			ata_port_warn(ap,
298 				      "EM read buffer size too large: "
299 				      "buffer size %u, page size %lu\n",
300 				      hpriv->em_buf_sz, PAGE_SIZE);
301 		count = PAGE_SIZE;
302 	}
303 
304 	for (i = 0; i < count; i += 4) {
305 		msg = readl(em_mmio + i);
306 		buf[i] = msg & 0xff;
307 		buf[i + 1] = (msg >> 8) & 0xff;
308 		buf[i + 2] = (msg >> 16) & 0xff;
309 		buf[i + 3] = (msg >> 24) & 0xff;
310 	}
311 
312 	spin_unlock_irqrestore(ap->lock, flags);
313 
314 	return i;
315 }
316 
317 static ssize_t ahci_store_em_buffer(struct device *dev,
318 				    struct device_attribute *attr,
319 				    const char *buf, size_t size)
320 {
321 	struct Scsi_Host *shost = class_to_shost(dev);
322 	struct ata_port *ap = ata_shost_to_port(shost);
323 	struct ahci_host_priv *hpriv = ap->host->private_data;
324 	void __iomem *mmio = hpriv->mmio;
325 	void __iomem *em_mmio = mmio + hpriv->em_loc;
326 	const unsigned char *msg_buf = buf;
327 	u32 em_ctl, msg;
328 	unsigned long flags;
329 	int i;
330 
331 	/* check size validity */
332 	if (!(ap->flags & ATA_FLAG_EM) ||
333 	    !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO) ||
334 	    size % 4 || size > hpriv->em_buf_sz)
335 		return -EINVAL;
336 
337 	spin_lock_irqsave(ap->lock, flags);
338 
339 	em_ctl = readl(mmio + HOST_EM_CTL);
340 	if (em_ctl & EM_CTL_TM) {
341 		spin_unlock_irqrestore(ap->lock, flags);
342 		return -EBUSY;
343 	}
344 
345 	for (i = 0; i < size; i += 4) {
346 		msg = msg_buf[i] | msg_buf[i + 1] << 8 |
347 		      msg_buf[i + 2] << 16 | msg_buf[i + 3] << 24;
348 		writel(msg, em_mmio + i);
349 	}
350 
351 	writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
352 
353 	spin_unlock_irqrestore(ap->lock, flags);
354 
355 	return size;
356 }
357 
358 static ssize_t ahci_show_em_supported(struct device *dev,
359 				      struct device_attribute *attr, char *buf)
360 {
361 	struct Scsi_Host *shost = class_to_shost(dev);
362 	struct ata_port *ap = ata_shost_to_port(shost);
363 	struct ahci_host_priv *hpriv = ap->host->private_data;
364 	void __iomem *mmio = hpriv->mmio;
365 	u32 em_ctl;
366 
367 	em_ctl = readl(mmio + HOST_EM_CTL);
368 
369 	return sprintf(buf, "%s%s%s%s\n",
370 		       em_ctl & EM_CTL_LED ? "led " : "",
371 		       em_ctl & EM_CTL_SAFTE ? "saf-te " : "",
372 		       em_ctl & EM_CTL_SES ? "ses-2 " : "",
373 		       em_ctl & EM_CTL_SGPIO ? "sgpio " : "");
374 }
375 
376 /**
377  *	ahci_save_initial_config - Save and fixup initial config values
378  *	@dev: target AHCI device
379  *	@hpriv: host private area to store config values
380  *	@force_port_map: force port map to a specified value
381  *	@mask_port_map: mask out particular bits from port map
382  *
383  *	Some registers containing configuration info might be setup by
384  *	BIOS and might be cleared on reset.  This function saves the
385  *	initial values of those registers into @hpriv such that they
386  *	can be restored after controller reset.
387  *
388  *	If inconsistent, config values are fixed up by this function.
389  *
390  *	LOCKING:
391  *	None.
392  */
393 void ahci_save_initial_config(struct device *dev,
394 			      struct ahci_host_priv *hpriv,
395 			      unsigned int force_port_map,
396 			      unsigned int mask_port_map)
397 {
398 	void __iomem *mmio = hpriv->mmio;
399 	u32 cap, cap2, vers, port_map;
400 	int i;
401 
402 	/* make sure AHCI mode is enabled before accessing CAP */
403 	ahci_enable_ahci(mmio);
404 
405 	/* Values prefixed with saved_ are written back to host after
406 	 * reset.  Values without are used for driver operation.
407 	 */
408 	hpriv->saved_cap = cap = readl(mmio + HOST_CAP);
409 	hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL);
410 
411 	/* CAP2 register is only defined for AHCI 1.2 and later */
412 	vers = readl(mmio + HOST_VERSION);
413 	if ((vers >> 16) > 1 ||
414 	   ((vers >> 16) == 1 && (vers & 0xFFFF) >= 0x200))
415 		hpriv->saved_cap2 = cap2 = readl(mmio + HOST_CAP2);
416 	else
417 		hpriv->saved_cap2 = cap2 = 0;
418 
419 	/* some chips have errata preventing 64bit use */
420 	if ((cap & HOST_CAP_64) && (hpriv->flags & AHCI_HFLAG_32BIT_ONLY)) {
421 		dev_info(dev, "controller can't do 64bit DMA, forcing 32bit\n");
422 		cap &= ~HOST_CAP_64;
423 	}
424 
425 	if ((cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_NO_NCQ)) {
426 		dev_info(dev, "controller can't do NCQ, turning off CAP_NCQ\n");
427 		cap &= ~HOST_CAP_NCQ;
428 	}
429 
430 	if (!(cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_YES_NCQ)) {
431 		dev_info(dev, "controller can do NCQ, turning on CAP_NCQ\n");
432 		cap |= HOST_CAP_NCQ;
433 	}
434 
435 	if ((cap & HOST_CAP_PMP) && (hpriv->flags & AHCI_HFLAG_NO_PMP)) {
436 		dev_info(dev, "controller can't do PMP, turning off CAP_PMP\n");
437 		cap &= ~HOST_CAP_PMP;
438 	}
439 
440 	if ((cap & HOST_CAP_SNTF) && (hpriv->flags & AHCI_HFLAG_NO_SNTF)) {
441 		dev_info(dev,
442 			 "controller can't do SNTF, turning off CAP_SNTF\n");
443 		cap &= ~HOST_CAP_SNTF;
444 	}
445 
446 	if (!(cap & HOST_CAP_FBS) && (hpriv->flags & AHCI_HFLAG_YES_FBS)) {
447 		dev_info(dev, "controller can do FBS, turning on CAP_FBS\n");
448 		cap |= HOST_CAP_FBS;
449 	}
450 
451 	if (force_port_map && port_map != force_port_map) {
452 		dev_info(dev, "forcing port_map 0x%x -> 0x%x\n",
453 			 port_map, force_port_map);
454 		port_map = force_port_map;
455 	}
456 
457 	if (mask_port_map) {
458 		dev_warn(dev, "masking port_map 0x%x -> 0x%x\n",
459 			port_map,
460 			port_map & mask_port_map);
461 		port_map &= mask_port_map;
462 	}
463 
464 	/* cross check port_map and cap.n_ports */
465 	if (port_map) {
466 		int map_ports = 0;
467 
468 		for (i = 0; i < AHCI_MAX_PORTS; i++)
469 			if (port_map & (1 << i))
470 				map_ports++;
471 
472 		/* If PI has more ports than n_ports, whine, clear
473 		 * port_map and let it be generated from n_ports.
474 		 */
475 		if (map_ports > ahci_nr_ports(cap)) {
476 			dev_warn(dev,
477 				 "implemented port map (0x%x) contains more ports than nr_ports (%u), using nr_ports\n",
478 				 port_map, ahci_nr_ports(cap));
479 			port_map = 0;
480 		}
481 	}
482 
483 	/* fabricate port_map from cap.nr_ports */
484 	if (!port_map) {
485 		port_map = (1 << ahci_nr_ports(cap)) - 1;
486 		dev_warn(dev, "forcing PORTS_IMPL to 0x%x\n", port_map);
487 
488 		/* write the fixed up value to the PI register */
489 		hpriv->saved_port_map = port_map;
490 	}
491 
492 	/* record values to use during operation */
493 	hpriv->cap = cap;
494 	hpriv->cap2 = cap2;
495 	hpriv->port_map = port_map;
496 }
497 EXPORT_SYMBOL_GPL(ahci_save_initial_config);
498 
499 /**
500  *	ahci_restore_initial_config - Restore initial config
501  *	@host: target ATA host
502  *
503  *	Restore initial config stored by ahci_save_initial_config().
504  *
505  *	LOCKING:
506  *	None.
507  */
508 static void ahci_restore_initial_config(struct ata_host *host)
509 {
510 	struct ahci_host_priv *hpriv = host->private_data;
511 	void __iomem *mmio = hpriv->mmio;
512 
513 	writel(hpriv->saved_cap, mmio + HOST_CAP);
514 	if (hpriv->saved_cap2)
515 		writel(hpriv->saved_cap2, mmio + HOST_CAP2);
516 	writel(hpriv->saved_port_map, mmio + HOST_PORTS_IMPL);
517 	(void) readl(mmio + HOST_PORTS_IMPL);	/* flush */
518 }
519 
520 static unsigned ahci_scr_offset(struct ata_port *ap, unsigned int sc_reg)
521 {
522 	static const int offset[] = {
523 		[SCR_STATUS]		= PORT_SCR_STAT,
524 		[SCR_CONTROL]		= PORT_SCR_CTL,
525 		[SCR_ERROR]		= PORT_SCR_ERR,
526 		[SCR_ACTIVE]		= PORT_SCR_ACT,
527 		[SCR_NOTIFICATION]	= PORT_SCR_NTF,
528 	};
529 	struct ahci_host_priv *hpriv = ap->host->private_data;
530 
531 	if (sc_reg < ARRAY_SIZE(offset) &&
532 	    (sc_reg != SCR_NOTIFICATION || (hpriv->cap & HOST_CAP_SNTF)))
533 		return offset[sc_reg];
534 	return 0;
535 }
536 
537 static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val)
538 {
539 	void __iomem *port_mmio = ahci_port_base(link->ap);
540 	int offset = ahci_scr_offset(link->ap, sc_reg);
541 
542 	if (offset) {
543 		*val = readl(port_mmio + offset);
544 		return 0;
545 	}
546 	return -EINVAL;
547 }
548 
549 static int ahci_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val)
550 {
551 	void __iomem *port_mmio = ahci_port_base(link->ap);
552 	int offset = ahci_scr_offset(link->ap, sc_reg);
553 
554 	if (offset) {
555 		writel(val, port_mmio + offset);
556 		return 0;
557 	}
558 	return -EINVAL;
559 }
560 
561 void ahci_start_engine(struct ata_port *ap)
562 {
563 	void __iomem *port_mmio = ahci_port_base(ap);
564 	u32 tmp;
565 
566 	/* start DMA */
567 	tmp = readl(port_mmio + PORT_CMD);
568 	tmp |= PORT_CMD_START;
569 	writel(tmp, port_mmio + PORT_CMD);
570 	readl(port_mmio + PORT_CMD); /* flush */
571 }
572 EXPORT_SYMBOL_GPL(ahci_start_engine);
573 
574 int ahci_stop_engine(struct ata_port *ap)
575 {
576 	void __iomem *port_mmio = ahci_port_base(ap);
577 	u32 tmp;
578 
579 	tmp = readl(port_mmio + PORT_CMD);
580 
581 	/* check if the HBA is idle */
582 	if ((tmp & (PORT_CMD_START | PORT_CMD_LIST_ON)) == 0)
583 		return 0;
584 
585 	/* setting HBA to idle */
586 	tmp &= ~PORT_CMD_START;
587 	writel(tmp, port_mmio + PORT_CMD);
588 
589 	/* wait for engine to stop. This could be as long as 500 msec */
590 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
591 				PORT_CMD_LIST_ON, PORT_CMD_LIST_ON, 1, 500);
592 	if (tmp & PORT_CMD_LIST_ON)
593 		return -EIO;
594 
595 	return 0;
596 }
597 EXPORT_SYMBOL_GPL(ahci_stop_engine);
598 
599 static void ahci_start_fis_rx(struct ata_port *ap)
600 {
601 	void __iomem *port_mmio = ahci_port_base(ap);
602 	struct ahci_host_priv *hpriv = ap->host->private_data;
603 	struct ahci_port_priv *pp = ap->private_data;
604 	u32 tmp;
605 
606 	/* set FIS registers */
607 	if (hpriv->cap & HOST_CAP_64)
608 		writel((pp->cmd_slot_dma >> 16) >> 16,
609 		       port_mmio + PORT_LST_ADDR_HI);
610 	writel(pp->cmd_slot_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);
611 
612 	if (hpriv->cap & HOST_CAP_64)
613 		writel((pp->rx_fis_dma >> 16) >> 16,
614 		       port_mmio + PORT_FIS_ADDR_HI);
615 	writel(pp->rx_fis_dma & 0xffffffff, port_mmio + PORT_FIS_ADDR);
616 
617 	/* enable FIS reception */
618 	tmp = readl(port_mmio + PORT_CMD);
619 	tmp |= PORT_CMD_FIS_RX;
620 	writel(tmp, port_mmio + PORT_CMD);
621 
622 	/* flush */
623 	readl(port_mmio + PORT_CMD);
624 }
625 
626 static int ahci_stop_fis_rx(struct ata_port *ap)
627 {
628 	void __iomem *port_mmio = ahci_port_base(ap);
629 	u32 tmp;
630 
631 	/* disable FIS reception */
632 	tmp = readl(port_mmio + PORT_CMD);
633 	tmp &= ~PORT_CMD_FIS_RX;
634 	writel(tmp, port_mmio + PORT_CMD);
635 
636 	/* wait for completion, spec says 500ms, give it 1000 */
637 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD, PORT_CMD_FIS_ON,
638 				PORT_CMD_FIS_ON, 10, 1000);
639 	if (tmp & PORT_CMD_FIS_ON)
640 		return -EBUSY;
641 
642 	return 0;
643 }
644 
645 static void ahci_power_up(struct ata_port *ap)
646 {
647 	struct ahci_host_priv *hpriv = ap->host->private_data;
648 	void __iomem *port_mmio = ahci_port_base(ap);
649 	u32 cmd;
650 
651 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
652 
653 	/* spin up device */
654 	if (hpriv->cap & HOST_CAP_SSS) {
655 		cmd |= PORT_CMD_SPIN_UP;
656 		writel(cmd, port_mmio + PORT_CMD);
657 	}
658 
659 	/* wake up link */
660 	writel(cmd | PORT_CMD_ICC_ACTIVE, port_mmio + PORT_CMD);
661 }
662 
663 static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
664 			unsigned int hints)
665 {
666 	struct ata_port *ap = link->ap;
667 	struct ahci_host_priv *hpriv = ap->host->private_data;
668 	struct ahci_port_priv *pp = ap->private_data;
669 	void __iomem *port_mmio = ahci_port_base(ap);
670 
671 	if (policy != ATA_LPM_MAX_POWER) {
672 		/*
673 		 * Disable interrupts on Phy Ready. This keeps us from
674 		 * getting woken up due to spurious phy ready
675 		 * interrupts.
676 		 */
677 		pp->intr_mask &= ~PORT_IRQ_PHYRDY;
678 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
679 
680 		sata_link_scr_lpm(link, policy, false);
681 	}
682 
683 	if (hpriv->cap & HOST_CAP_ALPM) {
684 		u32 cmd = readl(port_mmio + PORT_CMD);
685 
686 		if (policy == ATA_LPM_MAX_POWER || !(hints & ATA_LPM_HIPM)) {
687 			cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE);
688 			cmd |= PORT_CMD_ICC_ACTIVE;
689 
690 			writel(cmd, port_mmio + PORT_CMD);
691 			readl(port_mmio + PORT_CMD);
692 
693 			/* wait 10ms to be sure we've come out of LPM state */
694 			ata_msleep(ap, 10);
695 		} else {
696 			cmd |= PORT_CMD_ALPE;
697 			if (policy == ATA_LPM_MIN_POWER)
698 				cmd |= PORT_CMD_ASP;
699 
700 			/* write out new cmd value */
701 			writel(cmd, port_mmio + PORT_CMD);
702 		}
703 	}
704 
705 	if (policy == ATA_LPM_MAX_POWER) {
706 		sata_link_scr_lpm(link, policy, false);
707 
708 		/* turn PHYRDY IRQ back on */
709 		pp->intr_mask |= PORT_IRQ_PHYRDY;
710 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
711 	}
712 
713 	return 0;
714 }
715 
716 #ifdef CONFIG_PM
717 static void ahci_power_down(struct ata_port *ap)
718 {
719 	struct ahci_host_priv *hpriv = ap->host->private_data;
720 	void __iomem *port_mmio = ahci_port_base(ap);
721 	u32 cmd, scontrol;
722 
723 	if (!(hpriv->cap & HOST_CAP_SSS))
724 		return;
725 
726 	/* put device into listen mode, first set PxSCTL.DET to 0 */
727 	scontrol = readl(port_mmio + PORT_SCR_CTL);
728 	scontrol &= ~0xf;
729 	writel(scontrol, port_mmio + PORT_SCR_CTL);
730 
731 	/* then set PxCMD.SUD to 0 */
732 	cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
733 	cmd &= ~PORT_CMD_SPIN_UP;
734 	writel(cmd, port_mmio + PORT_CMD);
735 }
736 #endif
737 
738 static void ahci_start_port(struct ata_port *ap)
739 {
740 	struct ahci_host_priv *hpriv = ap->host->private_data;
741 	struct ahci_port_priv *pp = ap->private_data;
742 	struct ata_link *link;
743 	struct ahci_em_priv *emp;
744 	ssize_t rc;
745 	int i;
746 
747 	/* enable FIS reception */
748 	ahci_start_fis_rx(ap);
749 
750 	/* enable DMA */
751 	if (!(hpriv->flags & AHCI_HFLAG_DELAY_ENGINE))
752 		ahci_start_engine(ap);
753 
754 	/* turn on LEDs */
755 	if (ap->flags & ATA_FLAG_EM) {
756 		ata_for_each_link(link, ap, EDGE) {
757 			emp = &pp->em_priv[link->pmp];
758 
759 			/* EM Transmit bit maybe busy during init */
760 			for (i = 0; i < EM_MAX_RETRY; i++) {
761 				rc = ahci_transmit_led_message(ap,
762 							       emp->led_state,
763 							       4);
764 				if (rc == -EBUSY)
765 					ata_msleep(ap, 1);
766 				else
767 					break;
768 			}
769 		}
770 	}
771 
772 	if (ap->flags & ATA_FLAG_SW_ACTIVITY)
773 		ata_for_each_link(link, ap, EDGE)
774 			ahci_init_sw_activity(link);
775 
776 }
777 
778 static int ahci_deinit_port(struct ata_port *ap, const char **emsg)
779 {
780 	int rc;
781 
782 	/* disable DMA */
783 	rc = ahci_stop_engine(ap);
784 	if (rc) {
785 		*emsg = "failed to stop engine";
786 		return rc;
787 	}
788 
789 	/* disable FIS reception */
790 	rc = ahci_stop_fis_rx(ap);
791 	if (rc) {
792 		*emsg = "failed stop FIS RX";
793 		return rc;
794 	}
795 
796 	return 0;
797 }
798 
799 int ahci_reset_controller(struct ata_host *host)
800 {
801 	struct ahci_host_priv *hpriv = host->private_data;
802 	void __iomem *mmio = hpriv->mmio;
803 	u32 tmp;
804 
805 	/* we must be in AHCI mode, before using anything
806 	 * AHCI-specific, such as HOST_RESET.
807 	 */
808 	ahci_enable_ahci(mmio);
809 
810 	/* global controller reset */
811 	if (!ahci_skip_host_reset) {
812 		tmp = readl(mmio + HOST_CTL);
813 		if ((tmp & HOST_RESET) == 0) {
814 			writel(tmp | HOST_RESET, mmio + HOST_CTL);
815 			readl(mmio + HOST_CTL); /* flush */
816 		}
817 
818 		/*
819 		 * to perform host reset, OS should set HOST_RESET
820 		 * and poll until this bit is read to be "0".
821 		 * reset must complete within 1 second, or
822 		 * the hardware should be considered fried.
823 		 */
824 		tmp = ata_wait_register(NULL, mmio + HOST_CTL, HOST_RESET,
825 					HOST_RESET, 10, 1000);
826 
827 		if (tmp & HOST_RESET) {
828 			dev_err(host->dev, "controller reset failed (0x%x)\n",
829 				tmp);
830 			return -EIO;
831 		}
832 
833 		/* turn on AHCI mode */
834 		ahci_enable_ahci(mmio);
835 
836 		/* Some registers might be cleared on reset.  Restore
837 		 * initial values.
838 		 */
839 		ahci_restore_initial_config(host);
840 	} else
841 		dev_info(host->dev, "skipping global host reset\n");
842 
843 	return 0;
844 }
845 EXPORT_SYMBOL_GPL(ahci_reset_controller);
846 
847 static void ahci_sw_activity(struct ata_link *link)
848 {
849 	struct ata_port *ap = link->ap;
850 	struct ahci_port_priv *pp = ap->private_data;
851 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
852 
853 	if (!(link->flags & ATA_LFLAG_SW_ACTIVITY))
854 		return;
855 
856 	emp->activity++;
857 	if (!timer_pending(&emp->timer))
858 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(10));
859 }
860 
861 static void ahci_sw_activity_blink(unsigned long arg)
862 {
863 	struct ata_link *link = (struct ata_link *)arg;
864 	struct ata_port *ap = link->ap;
865 	struct ahci_port_priv *pp = ap->private_data;
866 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
867 	unsigned long led_message = emp->led_state;
868 	u32 activity_led_state;
869 	unsigned long flags;
870 
871 	led_message &= EM_MSG_LED_VALUE;
872 	led_message |= ap->port_no | (link->pmp << 8);
873 
874 	/* check to see if we've had activity.  If so,
875 	 * toggle state of LED and reset timer.  If not,
876 	 * turn LED to desired idle state.
877 	 */
878 	spin_lock_irqsave(ap->lock, flags);
879 	if (emp->saved_activity != emp->activity) {
880 		emp->saved_activity = emp->activity;
881 		/* get the current LED state */
882 		activity_led_state = led_message & EM_MSG_LED_VALUE_ON;
883 
884 		if (activity_led_state)
885 			activity_led_state = 0;
886 		else
887 			activity_led_state = 1;
888 
889 		/* clear old state */
890 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
891 
892 		/* toggle state */
893 		led_message |= (activity_led_state << 16);
894 		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(100));
895 	} else {
896 		/* switch to idle */
897 		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
898 		if (emp->blink_policy == BLINK_OFF)
899 			led_message |= (1 << 16);
900 	}
901 	spin_unlock_irqrestore(ap->lock, flags);
902 	ahci_transmit_led_message(ap, led_message, 4);
903 }
904 
905 static void ahci_init_sw_activity(struct ata_link *link)
906 {
907 	struct ata_port *ap = link->ap;
908 	struct ahci_port_priv *pp = ap->private_data;
909 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
910 
911 	/* init activity stats, setup timer */
912 	emp->saved_activity = emp->activity = 0;
913 	setup_timer(&emp->timer, ahci_sw_activity_blink, (unsigned long)link);
914 
915 	/* check our blink policy and set flag for link if it's enabled */
916 	if (emp->blink_policy)
917 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
918 }
919 
920 int ahci_reset_em(struct ata_host *host)
921 {
922 	struct ahci_host_priv *hpriv = host->private_data;
923 	void __iomem *mmio = hpriv->mmio;
924 	u32 em_ctl;
925 
926 	em_ctl = readl(mmio + HOST_EM_CTL);
927 	if ((em_ctl & EM_CTL_TM) || (em_ctl & EM_CTL_RST))
928 		return -EINVAL;
929 
930 	writel(em_ctl | EM_CTL_RST, mmio + HOST_EM_CTL);
931 	return 0;
932 }
933 EXPORT_SYMBOL_GPL(ahci_reset_em);
934 
935 static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
936 					ssize_t size)
937 {
938 	struct ahci_host_priv *hpriv = ap->host->private_data;
939 	struct ahci_port_priv *pp = ap->private_data;
940 	void __iomem *mmio = hpriv->mmio;
941 	u32 em_ctl;
942 	u32 message[] = {0, 0};
943 	unsigned long flags;
944 	int pmp;
945 	struct ahci_em_priv *emp;
946 
947 	/* get the slot number from the message */
948 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
949 	if (pmp < EM_MAX_SLOTS)
950 		emp = &pp->em_priv[pmp];
951 	else
952 		return -EINVAL;
953 
954 	spin_lock_irqsave(ap->lock, flags);
955 
956 	/*
957 	 * if we are still busy transmitting a previous message,
958 	 * do not allow
959 	 */
960 	em_ctl = readl(mmio + HOST_EM_CTL);
961 	if (em_ctl & EM_CTL_TM) {
962 		spin_unlock_irqrestore(ap->lock, flags);
963 		return -EBUSY;
964 	}
965 
966 	if (hpriv->em_msg_type & EM_MSG_TYPE_LED) {
967 		/*
968 		 * create message header - this is all zero except for
969 		 * the message size, which is 4 bytes.
970 		 */
971 		message[0] |= (4 << 8);
972 
973 		/* ignore 0:4 of byte zero, fill in port info yourself */
974 		message[1] = ((state & ~EM_MSG_LED_HBA_PORT) | ap->port_no);
975 
976 		/* write message to EM_LOC */
977 		writel(message[0], mmio + hpriv->em_loc);
978 		writel(message[1], mmio + hpriv->em_loc+4);
979 
980 		/*
981 		 * tell hardware to transmit the message
982 		 */
983 		writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
984 	}
985 
986 	/* save off new led state for port/slot */
987 	emp->led_state = state;
988 
989 	spin_unlock_irqrestore(ap->lock, flags);
990 	return size;
991 }
992 
993 static ssize_t ahci_led_show(struct ata_port *ap, char *buf)
994 {
995 	struct ahci_port_priv *pp = ap->private_data;
996 	struct ata_link *link;
997 	struct ahci_em_priv *emp;
998 	int rc = 0;
999 
1000 	ata_for_each_link(link, ap, EDGE) {
1001 		emp = &pp->em_priv[link->pmp];
1002 		rc += sprintf(buf, "%lx\n", emp->led_state);
1003 	}
1004 	return rc;
1005 }
1006 
1007 static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
1008 				size_t size)
1009 {
1010 	int state;
1011 	int pmp;
1012 	struct ahci_port_priv *pp = ap->private_data;
1013 	struct ahci_em_priv *emp;
1014 
1015 	state = simple_strtoul(buf, NULL, 0);
1016 
1017 	/* get the slot number from the message */
1018 	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
1019 	if (pmp < EM_MAX_SLOTS)
1020 		emp = &pp->em_priv[pmp];
1021 	else
1022 		return -EINVAL;
1023 
1024 	/* mask off the activity bits if we are in sw_activity
1025 	 * mode, user should turn off sw_activity before setting
1026 	 * activity led through em_message
1027 	 */
1028 	if (emp->blink_policy)
1029 		state &= ~EM_MSG_LED_VALUE_ACTIVITY;
1030 
1031 	return ahci_transmit_led_message(ap, state, size);
1032 }
1033 
1034 static ssize_t ahci_activity_store(struct ata_device *dev, enum sw_activity val)
1035 {
1036 	struct ata_link *link = dev->link;
1037 	struct ata_port *ap = link->ap;
1038 	struct ahci_port_priv *pp = ap->private_data;
1039 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1040 	u32 port_led_state = emp->led_state;
1041 
1042 	/* save the desired Activity LED behavior */
1043 	if (val == OFF) {
1044 		/* clear LFLAG */
1045 		link->flags &= ~(ATA_LFLAG_SW_ACTIVITY);
1046 
1047 		/* set the LED to OFF */
1048 		port_led_state &= EM_MSG_LED_VALUE_OFF;
1049 		port_led_state |= (ap->port_no | (link->pmp << 8));
1050 		ahci_transmit_led_message(ap, port_led_state, 4);
1051 	} else {
1052 		link->flags |= ATA_LFLAG_SW_ACTIVITY;
1053 		if (val == BLINK_OFF) {
1054 			/* set LED to ON for idle */
1055 			port_led_state &= EM_MSG_LED_VALUE_OFF;
1056 			port_led_state |= (ap->port_no | (link->pmp << 8));
1057 			port_led_state |= EM_MSG_LED_VALUE_ON; /* check this */
1058 			ahci_transmit_led_message(ap, port_led_state, 4);
1059 		}
1060 	}
1061 	emp->blink_policy = val;
1062 	return 0;
1063 }
1064 
1065 static ssize_t ahci_activity_show(struct ata_device *dev, char *buf)
1066 {
1067 	struct ata_link *link = dev->link;
1068 	struct ata_port *ap = link->ap;
1069 	struct ahci_port_priv *pp = ap->private_data;
1070 	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
1071 
1072 	/* display the saved value of activity behavior for this
1073 	 * disk.
1074 	 */
1075 	return sprintf(buf, "%d\n", emp->blink_policy);
1076 }
1077 
1078 static void ahci_port_init(struct device *dev, struct ata_port *ap,
1079 			   int port_no, void __iomem *mmio,
1080 			   void __iomem *port_mmio)
1081 {
1082 	const char *emsg = NULL;
1083 	int rc;
1084 	u32 tmp;
1085 
1086 	/* make sure port is not active */
1087 	rc = ahci_deinit_port(ap, &emsg);
1088 	if (rc)
1089 		dev_warn(dev, "%s (%d)\n", emsg, rc);
1090 
1091 	/* clear SError */
1092 	tmp = readl(port_mmio + PORT_SCR_ERR);
1093 	VPRINTK("PORT_SCR_ERR 0x%x\n", tmp);
1094 	writel(tmp, port_mmio + PORT_SCR_ERR);
1095 
1096 	/* clear port IRQ */
1097 	tmp = readl(port_mmio + PORT_IRQ_STAT);
1098 	VPRINTK("PORT_IRQ_STAT 0x%x\n", tmp);
1099 	if (tmp)
1100 		writel(tmp, port_mmio + PORT_IRQ_STAT);
1101 
1102 	writel(1 << port_no, mmio + HOST_IRQ_STAT);
1103 }
1104 
1105 void ahci_init_controller(struct ata_host *host)
1106 {
1107 	struct ahci_host_priv *hpriv = host->private_data;
1108 	void __iomem *mmio = hpriv->mmio;
1109 	int i;
1110 	void __iomem *port_mmio;
1111 	u32 tmp;
1112 
1113 	for (i = 0; i < host->n_ports; i++) {
1114 		struct ata_port *ap = host->ports[i];
1115 
1116 		port_mmio = ahci_port_base(ap);
1117 		if (ata_port_is_dummy(ap))
1118 			continue;
1119 
1120 		ahci_port_init(host->dev, ap, i, mmio, port_mmio);
1121 	}
1122 
1123 	tmp = readl(mmio + HOST_CTL);
1124 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1125 	writel(tmp | HOST_IRQ_EN, mmio + HOST_CTL);
1126 	tmp = readl(mmio + HOST_CTL);
1127 	VPRINTK("HOST_CTL 0x%x\n", tmp);
1128 }
1129 EXPORT_SYMBOL_GPL(ahci_init_controller);
1130 
1131 static void ahci_dev_config(struct ata_device *dev)
1132 {
1133 	struct ahci_host_priv *hpriv = dev->link->ap->host->private_data;
1134 
1135 	if (hpriv->flags & AHCI_HFLAG_SECT255) {
1136 		dev->max_sectors = 255;
1137 		ata_dev_info(dev,
1138 			     "SB600 AHCI: limiting to 255 sectors per cmd\n");
1139 	}
1140 }
1141 
1142 static unsigned int ahci_dev_classify(struct ata_port *ap)
1143 {
1144 	void __iomem *port_mmio = ahci_port_base(ap);
1145 	struct ata_taskfile tf;
1146 	u32 tmp;
1147 
1148 	tmp = readl(port_mmio + PORT_SIG);
1149 	tf.lbah		= (tmp >> 24)	& 0xff;
1150 	tf.lbam		= (tmp >> 16)	& 0xff;
1151 	tf.lbal		= (tmp >> 8)	& 0xff;
1152 	tf.nsect	= (tmp)		& 0xff;
1153 
1154 	return ata_dev_classify(&tf);
1155 }
1156 
1157 void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
1158 			u32 opts)
1159 {
1160 	dma_addr_t cmd_tbl_dma;
1161 
1162 	cmd_tbl_dma = pp->cmd_tbl_dma + tag * AHCI_CMD_TBL_SZ;
1163 
1164 	pp->cmd_slot[tag].opts = cpu_to_le32(opts);
1165 	pp->cmd_slot[tag].status = 0;
1166 	pp->cmd_slot[tag].tbl_addr = cpu_to_le32(cmd_tbl_dma & 0xffffffff);
1167 	pp->cmd_slot[tag].tbl_addr_hi = cpu_to_le32((cmd_tbl_dma >> 16) >> 16);
1168 }
1169 EXPORT_SYMBOL_GPL(ahci_fill_cmd_slot);
1170 
1171 int ahci_kick_engine(struct ata_port *ap)
1172 {
1173 	void __iomem *port_mmio = ahci_port_base(ap);
1174 	struct ahci_host_priv *hpriv = ap->host->private_data;
1175 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1176 	u32 tmp;
1177 	int busy, rc;
1178 
1179 	/* stop engine */
1180 	rc = ahci_stop_engine(ap);
1181 	if (rc)
1182 		goto out_restart;
1183 
1184 	/* need to do CLO?
1185 	 * always do CLO if PMP is attached (AHCI-1.3 9.2)
1186 	 */
1187 	busy = status & (ATA_BUSY | ATA_DRQ);
1188 	if (!busy && !sata_pmp_attached(ap)) {
1189 		rc = 0;
1190 		goto out_restart;
1191 	}
1192 
1193 	if (!(hpriv->cap & HOST_CAP_CLO)) {
1194 		rc = -EOPNOTSUPP;
1195 		goto out_restart;
1196 	}
1197 
1198 	/* perform CLO */
1199 	tmp = readl(port_mmio + PORT_CMD);
1200 	tmp |= PORT_CMD_CLO;
1201 	writel(tmp, port_mmio + PORT_CMD);
1202 
1203 	rc = 0;
1204 	tmp = ata_wait_register(ap, port_mmio + PORT_CMD,
1205 				PORT_CMD_CLO, PORT_CMD_CLO, 1, 500);
1206 	if (tmp & PORT_CMD_CLO)
1207 		rc = -EIO;
1208 
1209 	/* restart engine */
1210  out_restart:
1211 	ahci_start_engine(ap);
1212 	return rc;
1213 }
1214 EXPORT_SYMBOL_GPL(ahci_kick_engine);
1215 
1216 static int ahci_exec_polled_cmd(struct ata_port *ap, int pmp,
1217 				struct ata_taskfile *tf, int is_cmd, u16 flags,
1218 				unsigned long timeout_msec)
1219 {
1220 	const u32 cmd_fis_len = 5; /* five dwords */
1221 	struct ahci_port_priv *pp = ap->private_data;
1222 	void __iomem *port_mmio = ahci_port_base(ap);
1223 	u8 *fis = pp->cmd_tbl;
1224 	u32 tmp;
1225 
1226 	/* prep the command */
1227 	ata_tf_to_fis(tf, pmp, is_cmd, fis);
1228 	ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12));
1229 
1230 	/* issue & wait */
1231 	writel(1, port_mmio + PORT_CMD_ISSUE);
1232 
1233 	if (timeout_msec) {
1234 		tmp = ata_wait_register(ap, port_mmio + PORT_CMD_ISSUE,
1235 					0x1, 0x1, 1, timeout_msec);
1236 		if (tmp & 0x1) {
1237 			ahci_kick_engine(ap);
1238 			return -EBUSY;
1239 		}
1240 	} else
1241 		readl(port_mmio + PORT_CMD_ISSUE);	/* flush */
1242 
1243 	return 0;
1244 }
1245 
1246 int ahci_do_softreset(struct ata_link *link, unsigned int *class,
1247 		      int pmp, unsigned long deadline,
1248 		      int (*check_ready)(struct ata_link *link))
1249 {
1250 	struct ata_port *ap = link->ap;
1251 	struct ahci_host_priv *hpriv = ap->host->private_data;
1252 	const char *reason = NULL;
1253 	unsigned long now, msecs;
1254 	struct ata_taskfile tf;
1255 	int rc;
1256 
1257 	DPRINTK("ENTER\n");
1258 
1259 	/* prepare for SRST (AHCI-1.1 10.4.1) */
1260 	rc = ahci_kick_engine(ap);
1261 	if (rc && rc != -EOPNOTSUPP)
1262 		ata_link_warn(link, "failed to reset engine (errno=%d)\n", rc);
1263 
1264 	ata_tf_init(link->device, &tf);
1265 
1266 	/* issue the first D2H Register FIS */
1267 	msecs = 0;
1268 	now = jiffies;
1269 	if (time_after(deadline, now))
1270 		msecs = jiffies_to_msecs(deadline - now);
1271 
1272 	tf.ctl |= ATA_SRST;
1273 	if (ahci_exec_polled_cmd(ap, pmp, &tf, 0,
1274 				 AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY, msecs)) {
1275 		rc = -EIO;
1276 		reason = "1st FIS failed";
1277 		goto fail;
1278 	}
1279 
1280 	/* spec says at least 5us, but be generous and sleep for 1ms */
1281 	ata_msleep(ap, 1);
1282 
1283 	/* issue the second D2H Register FIS */
1284 	tf.ctl &= ~ATA_SRST;
1285 	ahci_exec_polled_cmd(ap, pmp, &tf, 0, 0, 0);
1286 
1287 	/* wait for link to become ready */
1288 	rc = ata_wait_after_reset(link, deadline, check_ready);
1289 	if (rc == -EBUSY && hpriv->flags & AHCI_HFLAG_SRST_TOUT_IS_OFFLINE) {
1290 		/*
1291 		 * Workaround for cases where link online status can't
1292 		 * be trusted.  Treat device readiness timeout as link
1293 		 * offline.
1294 		 */
1295 		ata_link_info(link, "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_err(link, "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_bad_pmp_check_ready(struct ata_link *link)
1333 {
1334 	void __iomem *port_mmio = ahci_port_base(link->ap);
1335 	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
1336 	u32 irq_status = readl(port_mmio + PORT_IRQ_STAT);
1337 
1338 	/*
1339 	 * There is no need to check TFDATA if BAD PMP is found due to HW bug,
1340 	 * which can save timeout delay.
1341 	 */
1342 	if (irq_status & PORT_IRQ_BAD_PMP)
1343 		return -EIO;
1344 
1345 	return ata_check_ready(status);
1346 }
1347 
1348 int ahci_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
1349 				unsigned long deadline)
1350 {
1351 	struct ata_port *ap = link->ap;
1352 	void __iomem *port_mmio = ahci_port_base(ap);
1353 	int pmp = sata_srst_pmp(link);
1354 	int rc;
1355 	u32 irq_sts;
1356 
1357 	DPRINTK("ENTER\n");
1358 
1359 	rc = ahci_do_softreset(link, class, pmp, deadline,
1360 			       ahci_bad_pmp_check_ready);
1361 
1362 	/*
1363 	 * Soft reset fails with IPMS set when PMP is enabled but
1364 	 * SATA HDD/ODD is connected to SATA port, do soft reset
1365 	 * again to port 0.
1366 	 */
1367 	if (rc == -EIO) {
1368 		irq_sts = readl(port_mmio + PORT_IRQ_STAT);
1369 		if (irq_sts & PORT_IRQ_BAD_PMP) {
1370 			ata_link_printk(link, KERN_WARNING,
1371 					"applying PMP SRST workaround "
1372 					"and retrying\n");
1373 			rc = ahci_do_softreset(link, class, 0, deadline,
1374 					       ahci_check_ready);
1375 		}
1376 	}
1377 
1378 	return rc;
1379 }
1380 
1381 static int ahci_hardreset(struct ata_link *link, unsigned int *class,
1382 			  unsigned long deadline)
1383 {
1384 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
1385 	struct ata_port *ap = link->ap;
1386 	struct ahci_port_priv *pp = ap->private_data;
1387 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
1388 	struct ata_taskfile tf;
1389 	bool online;
1390 	int rc;
1391 
1392 	DPRINTK("ENTER\n");
1393 
1394 	ahci_stop_engine(ap);
1395 
1396 	/* clear D2H reception area to properly wait for D2H FIS */
1397 	ata_tf_init(link->device, &tf);
1398 	tf.command = 0x80;
1399 	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
1400 
1401 	rc = sata_link_hardreset(link, timing, deadline, &online,
1402 				 ahci_check_ready);
1403 
1404 	ahci_start_engine(ap);
1405 
1406 	if (online)
1407 		*class = ahci_dev_classify(ap);
1408 
1409 	DPRINTK("EXIT, rc=%d, class=%u\n", rc, *class);
1410 	return rc;
1411 }
1412 
1413 static void ahci_postreset(struct ata_link *link, unsigned int *class)
1414 {
1415 	struct ata_port *ap = link->ap;
1416 	void __iomem *port_mmio = ahci_port_base(ap);
1417 	u32 new_tmp, tmp;
1418 
1419 	ata_std_postreset(link, class);
1420 
1421 	/* Make sure port's ATAPI bit is set appropriately */
1422 	new_tmp = tmp = readl(port_mmio + PORT_CMD);
1423 	if (*class == ATA_DEV_ATAPI)
1424 		new_tmp |= PORT_CMD_ATAPI;
1425 	else
1426 		new_tmp &= ~PORT_CMD_ATAPI;
1427 	if (new_tmp != tmp) {
1428 		writel(new_tmp, port_mmio + PORT_CMD);
1429 		readl(port_mmio + PORT_CMD); /* flush */
1430 	}
1431 }
1432 
1433 static unsigned int ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl)
1434 {
1435 	struct scatterlist *sg;
1436 	struct ahci_sg *ahci_sg = cmd_tbl + AHCI_CMD_TBL_HDR_SZ;
1437 	unsigned int si;
1438 
1439 	VPRINTK("ENTER\n");
1440 
1441 	/*
1442 	 * Next, the S/G list.
1443 	 */
1444 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
1445 		dma_addr_t addr = sg_dma_address(sg);
1446 		u32 sg_len = sg_dma_len(sg);
1447 
1448 		ahci_sg[si].addr = cpu_to_le32(addr & 0xffffffff);
1449 		ahci_sg[si].addr_hi = cpu_to_le32((addr >> 16) >> 16);
1450 		ahci_sg[si].flags_size = cpu_to_le32(sg_len - 1);
1451 	}
1452 
1453 	return si;
1454 }
1455 
1456 static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc)
1457 {
1458 	struct ata_port *ap = qc->ap;
1459 	struct ahci_port_priv *pp = ap->private_data;
1460 
1461 	if (!sata_pmp_attached(ap) || pp->fbs_enabled)
1462 		return ata_std_qc_defer(qc);
1463 	else
1464 		return sata_pmp_qc_defer_cmd_switch(qc);
1465 }
1466 
1467 static void ahci_qc_prep(struct ata_queued_cmd *qc)
1468 {
1469 	struct ata_port *ap = qc->ap;
1470 	struct ahci_port_priv *pp = ap->private_data;
1471 	int is_atapi = ata_is_atapi(qc->tf.protocol);
1472 	void *cmd_tbl;
1473 	u32 opts;
1474 	const u32 cmd_fis_len = 5; /* five dwords */
1475 	unsigned int n_elem;
1476 
1477 	/*
1478 	 * Fill in command table information.  First, the header,
1479 	 * a SATA Register - Host to Device command FIS.
1480 	 */
1481 	cmd_tbl = pp->cmd_tbl + qc->tag * AHCI_CMD_TBL_SZ;
1482 
1483 	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, cmd_tbl);
1484 	if (is_atapi) {
1485 		memset(cmd_tbl + AHCI_CMD_TBL_CDB, 0, 32);
1486 		memcpy(cmd_tbl + AHCI_CMD_TBL_CDB, qc->cdb, qc->dev->cdb_len);
1487 	}
1488 
1489 	n_elem = 0;
1490 	if (qc->flags & ATA_QCFLAG_DMAMAP)
1491 		n_elem = ahci_fill_sg(qc, cmd_tbl);
1492 
1493 	/*
1494 	 * Fill in command slot information.
1495 	 */
1496 	opts = cmd_fis_len | n_elem << 16 | (qc->dev->link->pmp << 12);
1497 	if (qc->tf.flags & ATA_TFLAG_WRITE)
1498 		opts |= AHCI_CMD_WRITE;
1499 	if (is_atapi)
1500 		opts |= AHCI_CMD_ATAPI | AHCI_CMD_PREFETCH;
1501 
1502 	ahci_fill_cmd_slot(pp, qc->tag, opts);
1503 }
1504 
1505 static void ahci_fbs_dec_intr(struct ata_port *ap)
1506 {
1507 	struct ahci_port_priv *pp = ap->private_data;
1508 	void __iomem *port_mmio = ahci_port_base(ap);
1509 	u32 fbs = readl(port_mmio + PORT_FBS);
1510 	int retries = 3;
1511 
1512 	DPRINTK("ENTER\n");
1513 	BUG_ON(!pp->fbs_enabled);
1514 
1515 	/* time to wait for DEC is not specified by AHCI spec,
1516 	 * add a retry loop for safety.
1517 	 */
1518 	writel(fbs | PORT_FBS_DEC, port_mmio + PORT_FBS);
1519 	fbs = readl(port_mmio + PORT_FBS);
1520 	while ((fbs & PORT_FBS_DEC) && retries--) {
1521 		udelay(1);
1522 		fbs = readl(port_mmio + PORT_FBS);
1523 	}
1524 
1525 	if (fbs & PORT_FBS_DEC)
1526 		dev_err(ap->host->dev, "failed to clear device error\n");
1527 }
1528 
1529 static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
1530 {
1531 	struct ahci_host_priv *hpriv = ap->host->private_data;
1532 	struct ahci_port_priv *pp = ap->private_data;
1533 	struct ata_eh_info *host_ehi = &ap->link.eh_info;
1534 	struct ata_link *link = NULL;
1535 	struct ata_queued_cmd *active_qc;
1536 	struct ata_eh_info *active_ehi;
1537 	bool fbs_need_dec = false;
1538 	u32 serror;
1539 
1540 	/* determine active link with error */
1541 	if (pp->fbs_enabled) {
1542 		void __iomem *port_mmio = ahci_port_base(ap);
1543 		u32 fbs = readl(port_mmio + PORT_FBS);
1544 		int pmp = fbs >> PORT_FBS_DWE_OFFSET;
1545 
1546 		if ((fbs & PORT_FBS_SDE) && (pmp < ap->nr_pmp_links) &&
1547 		    ata_link_online(&ap->pmp_link[pmp])) {
1548 			link = &ap->pmp_link[pmp];
1549 			fbs_need_dec = true;
1550 		}
1551 
1552 	} else
1553 		ata_for_each_link(link, ap, EDGE)
1554 			if (ata_link_active(link))
1555 				break;
1556 
1557 	if (!link)
1558 		link = &ap->link;
1559 
1560 	active_qc = ata_qc_from_tag(ap, link->active_tag);
1561 	active_ehi = &link->eh_info;
1562 
1563 	/* record irq stat */
1564 	ata_ehi_clear_desc(host_ehi);
1565 	ata_ehi_push_desc(host_ehi, "irq_stat 0x%08x", irq_stat);
1566 
1567 	/* AHCI needs SError cleared; otherwise, it might lock up */
1568 	ahci_scr_read(&ap->link, SCR_ERROR, &serror);
1569 	ahci_scr_write(&ap->link, SCR_ERROR, serror);
1570 	host_ehi->serror |= serror;
1571 
1572 	/* some controllers set IRQ_IF_ERR on device errors, ignore it */
1573 	if (hpriv->flags & AHCI_HFLAG_IGN_IRQ_IF_ERR)
1574 		irq_stat &= ~PORT_IRQ_IF_ERR;
1575 
1576 	if (irq_stat & PORT_IRQ_TF_ERR) {
1577 		/* If qc is active, charge it; otherwise, the active
1578 		 * link.  There's no active qc on NCQ errors.  It will
1579 		 * be determined by EH by reading log page 10h.
1580 		 */
1581 		if (active_qc)
1582 			active_qc->err_mask |= AC_ERR_DEV;
1583 		else
1584 			active_ehi->err_mask |= AC_ERR_DEV;
1585 
1586 		if (hpriv->flags & AHCI_HFLAG_IGN_SERR_INTERNAL)
1587 			host_ehi->serror &= ~SERR_INTERNAL;
1588 	}
1589 
1590 	if (irq_stat & PORT_IRQ_UNK_FIS) {
1591 		u32 *unk = (u32 *)(pp->rx_fis + RX_FIS_UNK);
1592 
1593 		active_ehi->err_mask |= AC_ERR_HSM;
1594 		active_ehi->action |= ATA_EH_RESET;
1595 		ata_ehi_push_desc(active_ehi,
1596 				  "unknown FIS %08x %08x %08x %08x" ,
1597 				  unk[0], unk[1], unk[2], unk[3]);
1598 	}
1599 
1600 	if (sata_pmp_attached(ap) && (irq_stat & PORT_IRQ_BAD_PMP)) {
1601 		active_ehi->err_mask |= AC_ERR_HSM;
1602 		active_ehi->action |= ATA_EH_RESET;
1603 		ata_ehi_push_desc(active_ehi, "incorrect PMP");
1604 	}
1605 
1606 	if (irq_stat & (PORT_IRQ_HBUS_ERR | PORT_IRQ_HBUS_DATA_ERR)) {
1607 		host_ehi->err_mask |= AC_ERR_HOST_BUS;
1608 		host_ehi->action |= ATA_EH_RESET;
1609 		ata_ehi_push_desc(host_ehi, "host bus error");
1610 	}
1611 
1612 	if (irq_stat & PORT_IRQ_IF_ERR) {
1613 		if (fbs_need_dec)
1614 			active_ehi->err_mask |= AC_ERR_DEV;
1615 		else {
1616 			host_ehi->err_mask |= AC_ERR_ATA_BUS;
1617 			host_ehi->action |= ATA_EH_RESET;
1618 		}
1619 
1620 		ata_ehi_push_desc(host_ehi, "interface fatal error");
1621 	}
1622 
1623 	if (irq_stat & (PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)) {
1624 		ata_ehi_hotplugged(host_ehi);
1625 		ata_ehi_push_desc(host_ehi, "%s",
1626 			irq_stat & PORT_IRQ_CONNECT ?
1627 			"connection status changed" : "PHY RDY changed");
1628 	}
1629 
1630 	/* okay, let's hand over to EH */
1631 
1632 	if (irq_stat & PORT_IRQ_FREEZE)
1633 		ata_port_freeze(ap);
1634 	else if (fbs_need_dec) {
1635 		ata_link_abort(link);
1636 		ahci_fbs_dec_intr(ap);
1637 	} else
1638 		ata_port_abort(ap);
1639 }
1640 
1641 static void ahci_port_intr(struct ata_port *ap)
1642 {
1643 	void __iomem *port_mmio = ahci_port_base(ap);
1644 	struct ata_eh_info *ehi = &ap->link.eh_info;
1645 	struct ahci_port_priv *pp = ap->private_data;
1646 	struct ahci_host_priv *hpriv = ap->host->private_data;
1647 	int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
1648 	u32 status, qc_active = 0;
1649 	int rc;
1650 
1651 	status = readl(port_mmio + PORT_IRQ_STAT);
1652 	writel(status, port_mmio + PORT_IRQ_STAT);
1653 
1654 	/* ignore BAD_PMP while resetting */
1655 	if (unlikely(resetting))
1656 		status &= ~PORT_IRQ_BAD_PMP;
1657 
1658 	/* if LPM is enabled, PHYRDY doesn't mean anything */
1659 	if (ap->link.lpm_policy > ATA_LPM_MAX_POWER) {
1660 		status &= ~PORT_IRQ_PHYRDY;
1661 		ahci_scr_write(&ap->link, SCR_ERROR, SERR_PHYRDY_CHG);
1662 	}
1663 
1664 	if (unlikely(status & PORT_IRQ_ERROR)) {
1665 		ahci_error_intr(ap, status);
1666 		return;
1667 	}
1668 
1669 	if (status & PORT_IRQ_SDB_FIS) {
1670 		/* If SNotification is available, leave notification
1671 		 * handling to sata_async_notification().  If not,
1672 		 * emulate it by snooping SDB FIS RX area.
1673 		 *
1674 		 * Snooping FIS RX area is probably cheaper than
1675 		 * poking SNotification but some constrollers which
1676 		 * implement SNotification, ICH9 for example, don't
1677 		 * store AN SDB FIS into receive area.
1678 		 */
1679 		if (hpriv->cap & HOST_CAP_SNTF)
1680 			sata_async_notification(ap);
1681 		else {
1682 			/* If the 'N' bit in word 0 of the FIS is set,
1683 			 * we just received asynchronous notification.
1684 			 * Tell libata about it.
1685 			 *
1686 			 * Lack of SNotification should not appear in
1687 			 * ahci 1.2, so the workaround is unnecessary
1688 			 * when FBS is enabled.
1689 			 */
1690 			if (pp->fbs_enabled)
1691 				WARN_ON_ONCE(1);
1692 			else {
1693 				const __le32 *f = pp->rx_fis + RX_FIS_SDB;
1694 				u32 f0 = le32_to_cpu(f[0]);
1695 				if (f0 & (1 << 15))
1696 					sata_async_notification(ap);
1697 			}
1698 		}
1699 	}
1700 
1701 	/* pp->active_link is not reliable once FBS is enabled, both
1702 	 * PORT_SCR_ACT and PORT_CMD_ISSUE should be checked because
1703 	 * NCQ and non-NCQ commands may be in flight at the same time.
1704 	 */
1705 	if (pp->fbs_enabled) {
1706 		if (ap->qc_active) {
1707 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1708 			qc_active |= readl(port_mmio + PORT_CMD_ISSUE);
1709 		}
1710 	} else {
1711 		/* pp->active_link is valid iff any command is in flight */
1712 		if (ap->qc_active && pp->active_link->sactive)
1713 			qc_active = readl(port_mmio + PORT_SCR_ACT);
1714 		else
1715 			qc_active = readl(port_mmio + PORT_CMD_ISSUE);
1716 	}
1717 
1718 
1719 	rc = ata_qc_complete_multiple(ap, qc_active);
1720 
1721 	/* while resetting, invalid completions are expected */
1722 	if (unlikely(rc < 0 && !resetting)) {
1723 		ehi->err_mask |= AC_ERR_HSM;
1724 		ehi->action |= ATA_EH_RESET;
1725 		ata_port_freeze(ap);
1726 	}
1727 }
1728 
1729 irqreturn_t ahci_interrupt(int irq, void *dev_instance)
1730 {
1731 	struct ata_host *host = dev_instance;
1732 	struct ahci_host_priv *hpriv;
1733 	unsigned int i, handled = 0;
1734 	void __iomem *mmio;
1735 	u32 irq_stat, irq_masked;
1736 
1737 	VPRINTK("ENTER\n");
1738 
1739 	hpriv = host->private_data;
1740 	mmio = hpriv->mmio;
1741 
1742 	/* sigh.  0xffffffff is a valid return from h/w */
1743 	irq_stat = readl(mmio + HOST_IRQ_STAT);
1744 	if (!irq_stat)
1745 		return IRQ_NONE;
1746 
1747 	irq_masked = irq_stat & hpriv->port_map;
1748 
1749 	spin_lock(&host->lock);
1750 
1751 	for (i = 0; i < host->n_ports; i++) {
1752 		struct ata_port *ap;
1753 
1754 		if (!(irq_masked & (1 << i)))
1755 			continue;
1756 
1757 		ap = host->ports[i];
1758 		if (ap) {
1759 			ahci_port_intr(ap);
1760 			VPRINTK("port %u\n", i);
1761 		} else {
1762 			VPRINTK("port %u (no irq)\n", i);
1763 			if (ata_ratelimit())
1764 				dev_warn(host->dev,
1765 					 "interrupt on disabled port %u\n", i);
1766 		}
1767 
1768 		handled = 1;
1769 	}
1770 
1771 	/* HOST_IRQ_STAT behaves as level triggered latch meaning that
1772 	 * it should be cleared after all the port events are cleared;
1773 	 * otherwise, it will raise a spurious interrupt after each
1774 	 * valid one.  Please read section 10.6.2 of ahci 1.1 for more
1775 	 * information.
1776 	 *
1777 	 * Also, use the unmasked value to clear interrupt as spurious
1778 	 * pending event on a dummy port might cause screaming IRQ.
1779 	 */
1780 	writel(irq_stat, mmio + HOST_IRQ_STAT);
1781 
1782 	spin_unlock(&host->lock);
1783 
1784 	VPRINTK("EXIT\n");
1785 
1786 	return IRQ_RETVAL(handled);
1787 }
1788 EXPORT_SYMBOL_GPL(ahci_interrupt);
1789 
1790 static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
1791 {
1792 	struct ata_port *ap = qc->ap;
1793 	void __iomem *port_mmio = ahci_port_base(ap);
1794 	struct ahci_port_priv *pp = ap->private_data;
1795 
1796 	/* Keep track of the currently active link.  It will be used
1797 	 * in completion path to determine whether NCQ phase is in
1798 	 * progress.
1799 	 */
1800 	pp->active_link = qc->dev->link;
1801 
1802 	if (qc->tf.protocol == ATA_PROT_NCQ)
1803 		writel(1 << qc->tag, port_mmio + PORT_SCR_ACT);
1804 
1805 	if (pp->fbs_enabled && pp->fbs_last_dev != qc->dev->link->pmp) {
1806 		u32 fbs = readl(port_mmio + PORT_FBS);
1807 		fbs &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC);
1808 		fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
1809 		writel(fbs, port_mmio + PORT_FBS);
1810 		pp->fbs_last_dev = qc->dev->link->pmp;
1811 	}
1812 
1813 	writel(1 << qc->tag, port_mmio + PORT_CMD_ISSUE);
1814 
1815 	ahci_sw_activity(qc->dev->link);
1816 
1817 	return 0;
1818 }
1819 
1820 static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
1821 {
1822 	struct ahci_port_priv *pp = qc->ap->private_data;
1823 	u8 *rx_fis = pp->rx_fis;
1824 
1825 	if (pp->fbs_enabled)
1826 		rx_fis += qc->dev->link->pmp * AHCI_RX_FIS_SZ;
1827 
1828 	/*
1829 	 * After a successful execution of an ATA PIO data-in command,
1830 	 * the device doesn't send D2H Reg FIS to update the TF and
1831 	 * the host should take TF and E_Status from the preceding PIO
1832 	 * Setup FIS.
1833 	 */
1834 	if (qc->tf.protocol == ATA_PROT_PIO && qc->dma_dir == DMA_FROM_DEVICE &&
1835 	    !(qc->flags & ATA_QCFLAG_FAILED)) {
1836 		ata_tf_from_fis(rx_fis + RX_FIS_PIO_SETUP, &qc->result_tf);
1837 		qc->result_tf.command = (rx_fis + RX_FIS_PIO_SETUP)[15];
1838 	} else
1839 		ata_tf_from_fis(rx_fis + RX_FIS_D2H_REG, &qc->result_tf);
1840 
1841 	return true;
1842 }
1843 
1844 static void ahci_freeze(struct ata_port *ap)
1845 {
1846 	void __iomem *port_mmio = ahci_port_base(ap);
1847 
1848 	/* turn IRQ off */
1849 	writel(0, port_mmio + PORT_IRQ_MASK);
1850 }
1851 
1852 static void ahci_thaw(struct ata_port *ap)
1853 {
1854 	struct ahci_host_priv *hpriv = ap->host->private_data;
1855 	void __iomem *mmio = hpriv->mmio;
1856 	void __iomem *port_mmio = ahci_port_base(ap);
1857 	u32 tmp;
1858 	struct ahci_port_priv *pp = ap->private_data;
1859 
1860 	/* clear IRQ */
1861 	tmp = readl(port_mmio + PORT_IRQ_STAT);
1862 	writel(tmp, port_mmio + PORT_IRQ_STAT);
1863 	writel(1 << ap->port_no, mmio + HOST_IRQ_STAT);
1864 
1865 	/* turn IRQ back on */
1866 	writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
1867 }
1868 
1869 static void ahci_error_handler(struct ata_port *ap)
1870 {
1871 	if (!(ap->pflags & ATA_PFLAG_FROZEN)) {
1872 		/* restart engine */
1873 		ahci_stop_engine(ap);
1874 		ahci_start_engine(ap);
1875 	}
1876 
1877 	sata_pmp_error_handler(ap);
1878 
1879 	if (!ata_dev_enabled(ap->link.device))
1880 		ahci_stop_engine(ap);
1881 }
1882 
1883 static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
1884 {
1885 	struct ata_port *ap = qc->ap;
1886 
1887 	/* make DMA engine forget about the failed command */
1888 	if (qc->flags & ATA_QCFLAG_FAILED)
1889 		ahci_kick_engine(ap);
1890 }
1891 
1892 static void ahci_enable_fbs(struct ata_port *ap)
1893 {
1894 	struct ahci_port_priv *pp = ap->private_data;
1895 	void __iomem *port_mmio = ahci_port_base(ap);
1896 	u32 fbs;
1897 	int rc;
1898 
1899 	if (!pp->fbs_supported)
1900 		return;
1901 
1902 	fbs = readl(port_mmio + PORT_FBS);
1903 	if (fbs & PORT_FBS_EN) {
1904 		pp->fbs_enabled = true;
1905 		pp->fbs_last_dev = -1; /* initialization */
1906 		return;
1907 	}
1908 
1909 	rc = ahci_stop_engine(ap);
1910 	if (rc)
1911 		return;
1912 
1913 	writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
1914 	fbs = readl(port_mmio + PORT_FBS);
1915 	if (fbs & PORT_FBS_EN) {
1916 		dev_info(ap->host->dev, "FBS is enabled\n");
1917 		pp->fbs_enabled = true;
1918 		pp->fbs_last_dev = -1; /* initialization */
1919 	} else
1920 		dev_err(ap->host->dev, "Failed to enable FBS\n");
1921 
1922 	ahci_start_engine(ap);
1923 }
1924 
1925 static void ahci_disable_fbs(struct ata_port *ap)
1926 {
1927 	struct ahci_port_priv *pp = ap->private_data;
1928 	void __iomem *port_mmio = ahci_port_base(ap);
1929 	u32 fbs;
1930 	int rc;
1931 
1932 	if (!pp->fbs_supported)
1933 		return;
1934 
1935 	fbs = readl(port_mmio + PORT_FBS);
1936 	if ((fbs & PORT_FBS_EN) == 0) {
1937 		pp->fbs_enabled = false;
1938 		return;
1939 	}
1940 
1941 	rc = ahci_stop_engine(ap);
1942 	if (rc)
1943 		return;
1944 
1945 	writel(fbs & ~PORT_FBS_EN, port_mmio + PORT_FBS);
1946 	fbs = readl(port_mmio + PORT_FBS);
1947 	if (fbs & PORT_FBS_EN)
1948 		dev_err(ap->host->dev, "Failed to disable FBS\n");
1949 	else {
1950 		dev_info(ap->host->dev, "FBS is disabled\n");
1951 		pp->fbs_enabled = false;
1952 	}
1953 
1954 	ahci_start_engine(ap);
1955 }
1956 
1957 static void ahci_pmp_attach(struct ata_port *ap)
1958 {
1959 	void __iomem *port_mmio = ahci_port_base(ap);
1960 	struct ahci_port_priv *pp = ap->private_data;
1961 	u32 cmd;
1962 
1963 	cmd = readl(port_mmio + PORT_CMD);
1964 	cmd |= PORT_CMD_PMP;
1965 	writel(cmd, port_mmio + PORT_CMD);
1966 
1967 	ahci_enable_fbs(ap);
1968 
1969 	pp->intr_mask |= PORT_IRQ_BAD_PMP;
1970 
1971 	/*
1972 	 * We must not change the port interrupt mask register if the
1973 	 * port is marked frozen, the value in pp->intr_mask will be
1974 	 * restored later when the port is thawed.
1975 	 *
1976 	 * Note that during initialization, the port is marked as
1977 	 * frozen since the irq handler is not yet registered.
1978 	 */
1979 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
1980 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
1981 }
1982 
1983 static void ahci_pmp_detach(struct ata_port *ap)
1984 {
1985 	void __iomem *port_mmio = ahci_port_base(ap);
1986 	struct ahci_port_priv *pp = ap->private_data;
1987 	u32 cmd;
1988 
1989 	ahci_disable_fbs(ap);
1990 
1991 	cmd = readl(port_mmio + PORT_CMD);
1992 	cmd &= ~PORT_CMD_PMP;
1993 	writel(cmd, port_mmio + PORT_CMD);
1994 
1995 	pp->intr_mask &= ~PORT_IRQ_BAD_PMP;
1996 
1997 	/* see comment above in ahci_pmp_attach() */
1998 	if (!(ap->pflags & ATA_PFLAG_FROZEN))
1999 		writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
2000 }
2001 
2002 int ahci_port_resume(struct ata_port *ap)
2003 {
2004 	ahci_power_up(ap);
2005 	ahci_start_port(ap);
2006 
2007 	if (sata_pmp_attached(ap))
2008 		ahci_pmp_attach(ap);
2009 	else
2010 		ahci_pmp_detach(ap);
2011 
2012 	return 0;
2013 }
2014 EXPORT_SYMBOL_GPL(ahci_port_resume);
2015 
2016 #ifdef CONFIG_PM
2017 static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg)
2018 {
2019 	const char *emsg = NULL;
2020 	int rc;
2021 
2022 	rc = ahci_deinit_port(ap, &emsg);
2023 	if (rc == 0)
2024 		ahci_power_down(ap);
2025 	else {
2026 		ata_port_err(ap, "%s (%d)\n", emsg, rc);
2027 		ata_port_freeze(ap);
2028 	}
2029 
2030 	return rc;
2031 }
2032 #endif
2033 
2034 static int ahci_port_start(struct ata_port *ap)
2035 {
2036 	struct ahci_host_priv *hpriv = ap->host->private_data;
2037 	struct device *dev = ap->host->dev;
2038 	struct ahci_port_priv *pp;
2039 	void *mem;
2040 	dma_addr_t mem_dma;
2041 	size_t dma_sz, rx_fis_sz;
2042 
2043 	pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
2044 	if (!pp)
2045 		return -ENOMEM;
2046 
2047 	/* check FBS capability */
2048 	if ((hpriv->cap & HOST_CAP_FBS) && sata_pmp_supported(ap)) {
2049 		void __iomem *port_mmio = ahci_port_base(ap);
2050 		u32 cmd = readl(port_mmio + PORT_CMD);
2051 		if (cmd & PORT_CMD_FBSCP)
2052 			pp->fbs_supported = true;
2053 		else if (hpriv->flags & AHCI_HFLAG_YES_FBS) {
2054 			dev_info(dev, "port %d can do FBS, forcing FBSCP\n",
2055 				 ap->port_no);
2056 			pp->fbs_supported = true;
2057 		} else
2058 			dev_warn(dev, "port %d is not capable of FBS\n",
2059 				 ap->port_no);
2060 	}
2061 
2062 	if (pp->fbs_supported) {
2063 		dma_sz = AHCI_PORT_PRIV_FBS_DMA_SZ;
2064 		rx_fis_sz = AHCI_RX_FIS_SZ * 16;
2065 	} else {
2066 		dma_sz = AHCI_PORT_PRIV_DMA_SZ;
2067 		rx_fis_sz = AHCI_RX_FIS_SZ;
2068 	}
2069 
2070 	mem = dmam_alloc_coherent(dev, dma_sz, &mem_dma, GFP_KERNEL);
2071 	if (!mem)
2072 		return -ENOMEM;
2073 	memset(mem, 0, dma_sz);
2074 
2075 	/*
2076 	 * First item in chunk of DMA memory: 32-slot command table,
2077 	 * 32 bytes each in size
2078 	 */
2079 	pp->cmd_slot = mem;
2080 	pp->cmd_slot_dma = mem_dma;
2081 
2082 	mem += AHCI_CMD_SLOT_SZ;
2083 	mem_dma += AHCI_CMD_SLOT_SZ;
2084 
2085 	/*
2086 	 * Second item: Received-FIS area
2087 	 */
2088 	pp->rx_fis = mem;
2089 	pp->rx_fis_dma = mem_dma;
2090 
2091 	mem += rx_fis_sz;
2092 	mem_dma += rx_fis_sz;
2093 
2094 	/*
2095 	 * Third item: data area for storing a single command
2096 	 * and its scatter-gather table
2097 	 */
2098 	pp->cmd_tbl = mem;
2099 	pp->cmd_tbl_dma = mem_dma;
2100 
2101 	/*
2102 	 * Save off initial list of interrupts to be enabled.
2103 	 * This could be changed later
2104 	 */
2105 	pp->intr_mask = DEF_PORT_IRQ;
2106 
2107 	ap->private_data = pp;
2108 
2109 	/* engage engines, captain */
2110 	return ahci_port_resume(ap);
2111 }
2112 
2113 static void ahci_port_stop(struct ata_port *ap)
2114 {
2115 	const char *emsg = NULL;
2116 	int rc;
2117 
2118 	/* de-initialize port */
2119 	rc = ahci_deinit_port(ap, &emsg);
2120 	if (rc)
2121 		ata_port_warn(ap, "%s (%d)\n", emsg, rc);
2122 }
2123 
2124 void ahci_print_info(struct ata_host *host, const char *scc_s)
2125 {
2126 	struct ahci_host_priv *hpriv = host->private_data;
2127 	void __iomem *mmio = hpriv->mmio;
2128 	u32 vers, cap, cap2, impl, speed;
2129 	const char *speed_s;
2130 
2131 	vers = readl(mmio + HOST_VERSION);
2132 	cap = hpriv->cap;
2133 	cap2 = hpriv->cap2;
2134 	impl = hpriv->port_map;
2135 
2136 	speed = (cap >> 20) & 0xf;
2137 	if (speed == 1)
2138 		speed_s = "1.5";
2139 	else if (speed == 2)
2140 		speed_s = "3";
2141 	else if (speed == 3)
2142 		speed_s = "6";
2143 	else
2144 		speed_s = "?";
2145 
2146 	dev_info(host->dev,
2147 		"AHCI %02x%02x.%02x%02x "
2148 		"%u slots %u ports %s Gbps 0x%x impl %s mode\n"
2149 		,
2150 
2151 		(vers >> 24) & 0xff,
2152 		(vers >> 16) & 0xff,
2153 		(vers >> 8) & 0xff,
2154 		vers & 0xff,
2155 
2156 		((cap >> 8) & 0x1f) + 1,
2157 		(cap & 0x1f) + 1,
2158 		speed_s,
2159 		impl,
2160 		scc_s);
2161 
2162 	dev_info(host->dev,
2163 		"flags: "
2164 		"%s%s%s%s%s%s%s"
2165 		"%s%s%s%s%s%s%s"
2166 		"%s%s%s%s%s%s\n"
2167 		,
2168 
2169 		cap & HOST_CAP_64 ? "64bit " : "",
2170 		cap & HOST_CAP_NCQ ? "ncq " : "",
2171 		cap & HOST_CAP_SNTF ? "sntf " : "",
2172 		cap & HOST_CAP_MPS ? "ilck " : "",
2173 		cap & HOST_CAP_SSS ? "stag " : "",
2174 		cap & HOST_CAP_ALPM ? "pm " : "",
2175 		cap & HOST_CAP_LED ? "led " : "",
2176 		cap & HOST_CAP_CLO ? "clo " : "",
2177 		cap & HOST_CAP_ONLY ? "only " : "",
2178 		cap & HOST_CAP_PMP ? "pmp " : "",
2179 		cap & HOST_CAP_FBS ? "fbs " : "",
2180 		cap & HOST_CAP_PIO_MULTI ? "pio " : "",
2181 		cap & HOST_CAP_SSC ? "slum " : "",
2182 		cap & HOST_CAP_PART ? "part " : "",
2183 		cap & HOST_CAP_CCC ? "ccc " : "",
2184 		cap & HOST_CAP_EMS ? "ems " : "",
2185 		cap & HOST_CAP_SXS ? "sxs " : "",
2186 		cap2 & HOST_CAP2_APST ? "apst " : "",
2187 		cap2 & HOST_CAP2_NVMHCI ? "nvmp " : "",
2188 		cap2 & HOST_CAP2_BOH ? "boh " : ""
2189 		);
2190 }
2191 EXPORT_SYMBOL_GPL(ahci_print_info);
2192 
2193 void ahci_set_em_messages(struct ahci_host_priv *hpriv,
2194 			  struct ata_port_info *pi)
2195 {
2196 	u8 messages;
2197 	void __iomem *mmio = hpriv->mmio;
2198 	u32 em_loc = readl(mmio + HOST_EM_LOC);
2199 	u32 em_ctl = readl(mmio + HOST_EM_CTL);
2200 
2201 	if (!ahci_em_messages || !(hpriv->cap & HOST_CAP_EMS))
2202 		return;
2203 
2204 	messages = (em_ctl & EM_CTRL_MSG_TYPE) >> 16;
2205 
2206 	if (messages) {
2207 		/* store em_loc */
2208 		hpriv->em_loc = ((em_loc >> 16) * 4);
2209 		hpriv->em_buf_sz = ((em_loc & 0xff) * 4);
2210 		hpriv->em_msg_type = messages;
2211 		pi->flags |= ATA_FLAG_EM;
2212 		if (!(em_ctl & EM_CTL_ALHD))
2213 			pi->flags |= ATA_FLAG_SW_ACTIVITY;
2214 	}
2215 }
2216 EXPORT_SYMBOL_GPL(ahci_set_em_messages);
2217 
2218 MODULE_AUTHOR("Jeff Garzik");
2219 MODULE_DESCRIPTION("Common AHCI SATA low-level routines");
2220 MODULE_LICENSE("GPL");
2221