xref: /linux/drivers/ata/sata_via.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /*
2  *  sata_via.c - VIA Serial ATA controllers
3  *
4  *  Maintained by:  Tejun Heo <tj@kernel.org>
5  * 		   Please ALWAYS copy linux-ide@vger.kernel.org
6  *		   on emails.
7  *
8  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
9  *  Copyright 2003-2004 Jeff Garzik
10  *
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2, or (at your option)
15  *  any later version.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; see the file COPYING.  If not, write to
24  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  *
27  *  libata documentation is available via 'make {ps|pdf}docs',
28  *  as Documentation/driver-api/libata.rst
29  *
30  *  Hardware documentation available under NDA.
31  *
32  *
33  *
34  */
35 
36 #include <linux/kernel.h>
37 #include <linux/module.h>
38 #include <linux/pci.h>
39 #include <linux/blkdev.h>
40 #include <linux/delay.h>
41 #include <linux/device.h>
42 #include <scsi/scsi.h>
43 #include <scsi/scsi_cmnd.h>
44 #include <scsi/scsi_host.h>
45 #include <linux/libata.h>
46 
47 #define DRV_NAME	"sata_via"
48 #define DRV_VERSION	"2.6"
49 
50 /*
51  * vt8251 is different from other sata controllers of VIA.  It has two
52  * channels, each channel has both Master and Slave slot.
53  */
54 enum board_ids_enum {
55 	vt6420,
56 	vt6421,
57 	vt8251,
58 };
59 
60 enum {
61 	SATA_CHAN_ENAB		= 0x40, /* SATA channel enable */
62 	SATA_INT_GATE		= 0x41, /* SATA interrupt gating */
63 	SATA_NATIVE_MODE	= 0x42, /* Native mode enable */
64 	SVIA_MISC_3		= 0x46,	/* Miscellaneous Control III */
65 	PATA_UDMA_TIMING	= 0xB3, /* PATA timing for DMA/ cable detect */
66 	PATA_PIO_TIMING		= 0xAB, /* PATA timing register */
67 
68 	PORT0			= (1 << 1),
69 	PORT1			= (1 << 0),
70 	ALL_PORTS		= PORT0 | PORT1,
71 
72 	NATIVE_MODE_ALL		= (1 << 7) | (1 << 6) | (1 << 5) | (1 << 4),
73 
74 	SATA_EXT_PHY		= (1 << 6), /* 0==use PATA, 1==ext phy */
75 
76 	SATA_HOTPLUG		= (1 << 5), /* enable IRQ on hotplug */
77 };
78 
79 struct svia_priv {
80 	bool			wd_workaround;
81 };
82 
83 static int vt6420_hotplug;
84 module_param_named(vt6420_hotplug, vt6420_hotplug, int, 0644);
85 MODULE_PARM_DESC(vt6420_hotplug, "Enable hot-plug support for VT6420 (0=Don't support, 1=support)");
86 
87 static int svia_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
88 #ifdef CONFIG_PM_SLEEP
89 static int svia_pci_device_resume(struct pci_dev *pdev);
90 #endif
91 static int svia_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val);
92 static int svia_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val);
93 static int vt8251_scr_read(struct ata_link *link, unsigned int scr, u32 *val);
94 static int vt8251_scr_write(struct ata_link *link, unsigned int scr, u32 val);
95 static void svia_tf_load(struct ata_port *ap, const struct ata_taskfile *tf);
96 static void svia_noop_freeze(struct ata_port *ap);
97 static int vt6420_prereset(struct ata_link *link, unsigned long deadline);
98 static void vt6420_bmdma_start(struct ata_queued_cmd *qc);
99 static int vt6421_pata_cable_detect(struct ata_port *ap);
100 static void vt6421_set_pio_mode(struct ata_port *ap, struct ata_device *adev);
101 static void vt6421_set_dma_mode(struct ata_port *ap, struct ata_device *adev);
102 static void vt6421_error_handler(struct ata_port *ap);
103 
104 static const struct pci_device_id svia_pci_tbl[] = {
105 	{ PCI_VDEVICE(VIA, 0x5337), vt6420 },
106 	{ PCI_VDEVICE(VIA, 0x0591), vt6420 }, /* 2 sata chnls (Master) */
107 	{ PCI_VDEVICE(VIA, 0x3149), vt6420 }, /* 2 sata chnls (Master) */
108 	{ PCI_VDEVICE(VIA, 0x3249), vt6421 }, /* 2 sata chnls, 1 pata chnl */
109 	{ PCI_VDEVICE(VIA, 0x5372), vt6420 },
110 	{ PCI_VDEVICE(VIA, 0x7372), vt6420 },
111 	{ PCI_VDEVICE(VIA, 0x5287), vt8251 }, /* 2 sata chnls (Master/Slave) */
112 	{ PCI_VDEVICE(VIA, 0x9000), vt8251 },
113 
114 	{ }	/* terminate list */
115 };
116 
117 static struct pci_driver svia_pci_driver = {
118 	.name			= DRV_NAME,
119 	.id_table		= svia_pci_tbl,
120 	.probe			= svia_init_one,
121 #ifdef CONFIG_PM_SLEEP
122 	.suspend		= ata_pci_device_suspend,
123 	.resume			= svia_pci_device_resume,
124 #endif
125 	.remove			= ata_pci_remove_one,
126 };
127 
128 static struct scsi_host_template svia_sht = {
129 	ATA_BMDMA_SHT(DRV_NAME),
130 };
131 
132 static struct ata_port_operations svia_base_ops = {
133 	.inherits		= &ata_bmdma_port_ops,
134 	.sff_tf_load		= svia_tf_load,
135 };
136 
137 static struct ata_port_operations vt6420_sata_ops = {
138 	.inherits		= &svia_base_ops,
139 	.freeze			= svia_noop_freeze,
140 	.prereset		= vt6420_prereset,
141 	.bmdma_start		= vt6420_bmdma_start,
142 };
143 
144 static struct ata_port_operations vt6421_pata_ops = {
145 	.inherits		= &svia_base_ops,
146 	.cable_detect		= vt6421_pata_cable_detect,
147 	.set_piomode		= vt6421_set_pio_mode,
148 	.set_dmamode		= vt6421_set_dma_mode,
149 };
150 
151 static struct ata_port_operations vt6421_sata_ops = {
152 	.inherits		= &svia_base_ops,
153 	.scr_read		= svia_scr_read,
154 	.scr_write		= svia_scr_write,
155 	.error_handler		= vt6421_error_handler,
156 };
157 
158 static struct ata_port_operations vt8251_ops = {
159 	.inherits		= &svia_base_ops,
160 	.hardreset		= sata_std_hardreset,
161 	.scr_read		= vt8251_scr_read,
162 	.scr_write		= vt8251_scr_write,
163 };
164 
165 static const struct ata_port_info vt6420_port_info = {
166 	.flags		= ATA_FLAG_SATA,
167 	.pio_mask	= ATA_PIO4,
168 	.mwdma_mask	= ATA_MWDMA2,
169 	.udma_mask	= ATA_UDMA6,
170 	.port_ops	= &vt6420_sata_ops,
171 };
172 
173 static const struct ata_port_info vt6421_sport_info = {
174 	.flags		= ATA_FLAG_SATA,
175 	.pio_mask	= ATA_PIO4,
176 	.mwdma_mask	= ATA_MWDMA2,
177 	.udma_mask	= ATA_UDMA6,
178 	.port_ops	= &vt6421_sata_ops,
179 };
180 
181 static const struct ata_port_info vt6421_pport_info = {
182 	.flags		= ATA_FLAG_SLAVE_POSS,
183 	.pio_mask	= ATA_PIO4,
184 	/* No MWDMA */
185 	.udma_mask	= ATA_UDMA6,
186 	.port_ops	= &vt6421_pata_ops,
187 };
188 
189 static const struct ata_port_info vt8251_port_info = {
190 	.flags		= ATA_FLAG_SATA | ATA_FLAG_SLAVE_POSS,
191 	.pio_mask	= ATA_PIO4,
192 	.mwdma_mask	= ATA_MWDMA2,
193 	.udma_mask	= ATA_UDMA6,
194 	.port_ops	= &vt8251_ops,
195 };
196 
197 MODULE_AUTHOR("Jeff Garzik");
198 MODULE_DESCRIPTION("SCSI low-level driver for VIA SATA controllers");
199 MODULE_LICENSE("GPL");
200 MODULE_DEVICE_TABLE(pci, svia_pci_tbl);
201 MODULE_VERSION(DRV_VERSION);
202 
203 static int svia_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val)
204 {
205 	if (sc_reg > SCR_CONTROL)
206 		return -EINVAL;
207 	*val = ioread32(link->ap->ioaddr.scr_addr + (4 * sc_reg));
208 	return 0;
209 }
210 
211 static int svia_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val)
212 {
213 	if (sc_reg > SCR_CONTROL)
214 		return -EINVAL;
215 	iowrite32(val, link->ap->ioaddr.scr_addr + (4 * sc_reg));
216 	return 0;
217 }
218 
219 static int vt8251_scr_read(struct ata_link *link, unsigned int scr, u32 *val)
220 {
221 	static const u8 ipm_tbl[] = { 1, 2, 6, 0 };
222 	struct pci_dev *pdev = to_pci_dev(link->ap->host->dev);
223 	int slot = 2 * link->ap->port_no + link->pmp;
224 	u32 v = 0;
225 	u8 raw;
226 
227 	switch (scr) {
228 	case SCR_STATUS:
229 		pci_read_config_byte(pdev, 0xA0 + slot, &raw);
230 
231 		/* read the DET field, bit0 and 1 of the config byte */
232 		v |= raw & 0x03;
233 
234 		/* read the SPD field, bit4 of the configure byte */
235 		if (raw & (1 << 4))
236 			v |= 0x02 << 4;
237 		else
238 			v |= 0x01 << 4;
239 
240 		/* read the IPM field, bit2 and 3 of the config byte */
241 		v |= ipm_tbl[(raw >> 2) & 0x3];
242 		break;
243 
244 	case SCR_ERROR:
245 		/* devices other than 5287 uses 0xA8 as base */
246 		WARN_ON(pdev->device != 0x5287);
247 		pci_read_config_dword(pdev, 0xB0 + slot * 4, &v);
248 		break;
249 
250 	case SCR_CONTROL:
251 		pci_read_config_byte(pdev, 0xA4 + slot, &raw);
252 
253 		/* read the DET field, bit0 and bit1 */
254 		v |= ((raw & 0x02) << 1) | (raw & 0x01);
255 
256 		/* read the IPM field, bit2 and bit3 */
257 		v |= ((raw >> 2) & 0x03) << 8;
258 		break;
259 
260 	default:
261 		return -EINVAL;
262 	}
263 
264 	*val = v;
265 	return 0;
266 }
267 
268 static int vt8251_scr_write(struct ata_link *link, unsigned int scr, u32 val)
269 {
270 	struct pci_dev *pdev = to_pci_dev(link->ap->host->dev);
271 	int slot = 2 * link->ap->port_no + link->pmp;
272 	u32 v = 0;
273 
274 	switch (scr) {
275 	case SCR_ERROR:
276 		/* devices other than 5287 uses 0xA8 as base */
277 		WARN_ON(pdev->device != 0x5287);
278 		pci_write_config_dword(pdev, 0xB0 + slot * 4, val);
279 		return 0;
280 
281 	case SCR_CONTROL:
282 		/* set the DET field */
283 		v |= ((val & 0x4) >> 1) | (val & 0x1);
284 
285 		/* set the IPM field */
286 		v |= ((val >> 8) & 0x3) << 2;
287 
288 		pci_write_config_byte(pdev, 0xA4 + slot, v);
289 		return 0;
290 
291 	default:
292 		return -EINVAL;
293 	}
294 }
295 
296 /**
297  *	svia_tf_load - send taskfile registers to host controller
298  *	@ap: Port to which output is sent
299  *	@tf: ATA taskfile register set
300  *
301  *	Outputs ATA taskfile to standard ATA host controller.
302  *
303  *	This is to fix the internal bug of via chipsets, which will
304  *	reset the device register after changing the IEN bit on ctl
305  *	register.
306  */
307 static void svia_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
308 {
309 	struct ata_taskfile ttf;
310 
311 	if (tf->ctl != ap->last_ctl)  {
312 		ttf = *tf;
313 		ttf.flags |= ATA_TFLAG_DEVICE;
314 		tf = &ttf;
315 	}
316 	ata_sff_tf_load(ap, tf);
317 }
318 
319 static void svia_noop_freeze(struct ata_port *ap)
320 {
321 	/* Some VIA controllers choke if ATA_NIEN is manipulated in
322 	 * certain way.  Leave it alone and just clear pending IRQ.
323 	 */
324 	ap->ops->sff_check_status(ap);
325 	ata_bmdma_irq_clear(ap);
326 }
327 
328 /**
329  *	vt6420_prereset - prereset for vt6420
330  *	@link: target ATA link
331  *	@deadline: deadline jiffies for the operation
332  *
333  *	SCR registers on vt6420 are pieces of shit and may hang the
334  *	whole machine completely if accessed with the wrong timing.
335  *	To avoid such catastrophe, vt6420 doesn't provide generic SCR
336  *	access operations, but uses SStatus and SControl only during
337  *	boot probing in controlled way.
338  *
339  *	As the old (pre EH update) probing code is proven to work, we
340  *	strictly follow the access pattern.
341  *
342  *	LOCKING:
343  *	Kernel thread context (may sleep)
344  *
345  *	RETURNS:
346  *	0 on success, -errno otherwise.
347  */
348 static int vt6420_prereset(struct ata_link *link, unsigned long deadline)
349 {
350 	struct ata_port *ap = link->ap;
351 	struct ata_eh_context *ehc = &ap->link.eh_context;
352 	unsigned long timeout = jiffies + (HZ * 5);
353 	u32 sstatus, scontrol;
354 	int online;
355 
356 	/* don't do any SCR stuff if we're not loading */
357 	if (!(ap->pflags & ATA_PFLAG_LOADING))
358 		goto skip_scr;
359 
360 	/* Resume phy.  This is the old SATA resume sequence */
361 	svia_scr_write(link, SCR_CONTROL, 0x300);
362 	svia_scr_read(link, SCR_CONTROL, &scontrol); /* flush */
363 
364 	/* wait for phy to become ready, if necessary */
365 	do {
366 		ata_msleep(link->ap, 200);
367 		svia_scr_read(link, SCR_STATUS, &sstatus);
368 		if ((sstatus & 0xf) != 1)
369 			break;
370 	} while (time_before(jiffies, timeout));
371 
372 	/* open code sata_print_link_status() */
373 	svia_scr_read(link, SCR_STATUS, &sstatus);
374 	svia_scr_read(link, SCR_CONTROL, &scontrol);
375 
376 	online = (sstatus & 0xf) == 0x3;
377 
378 	ata_port_info(ap,
379 		      "SATA link %s 1.5 Gbps (SStatus %X SControl %X)\n",
380 		      online ? "up" : "down", sstatus, scontrol);
381 
382 	/* SStatus is read one more time */
383 	svia_scr_read(link, SCR_STATUS, &sstatus);
384 
385 	if (!online) {
386 		/* tell EH to bail */
387 		ehc->i.action &= ~ATA_EH_RESET;
388 		return 0;
389 	}
390 
391  skip_scr:
392 	/* wait for !BSY */
393 	ata_sff_wait_ready(link, deadline);
394 
395 	return 0;
396 }
397 
398 static void vt6420_bmdma_start(struct ata_queued_cmd *qc)
399 {
400 	struct ata_port *ap = qc->ap;
401 	if ((qc->tf.command == ATA_CMD_PACKET) &&
402 	    (qc->scsicmd->sc_data_direction == DMA_TO_DEVICE)) {
403 		/* Prevents corruption on some ATAPI burners */
404 		ata_sff_pause(ap);
405 	}
406 	ata_bmdma_start(qc);
407 }
408 
409 static int vt6421_pata_cable_detect(struct ata_port *ap)
410 {
411 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
412 	u8 tmp;
413 
414 	pci_read_config_byte(pdev, PATA_UDMA_TIMING, &tmp);
415 	if (tmp & 0x10)
416 		return ATA_CBL_PATA40;
417 	return ATA_CBL_PATA80;
418 }
419 
420 static void vt6421_set_pio_mode(struct ata_port *ap, struct ata_device *adev)
421 {
422 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
423 	static const u8 pio_bits[] = { 0xA8, 0x65, 0x65, 0x31, 0x20 };
424 	pci_write_config_byte(pdev, PATA_PIO_TIMING - adev->devno,
425 			      pio_bits[adev->pio_mode - XFER_PIO_0]);
426 }
427 
428 static void vt6421_set_dma_mode(struct ata_port *ap, struct ata_device *adev)
429 {
430 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
431 	static const u8 udma_bits[] = { 0xEE, 0xE8, 0xE6, 0xE4, 0xE2, 0xE1, 0xE0, 0xE0 };
432 	pci_write_config_byte(pdev, PATA_UDMA_TIMING - adev->devno,
433 			      udma_bits[adev->dma_mode - XFER_UDMA_0]);
434 }
435 
436 static const unsigned int svia_bar_sizes[] = {
437 	8, 4, 8, 4, 16, 256
438 };
439 
440 static const unsigned int vt6421_bar_sizes[] = {
441 	16, 16, 16, 16, 32, 128
442 };
443 
444 static void __iomem *svia_scr_addr(void __iomem *addr, unsigned int port)
445 {
446 	return addr + (port * 128);
447 }
448 
449 static void __iomem *vt6421_scr_addr(void __iomem *addr, unsigned int port)
450 {
451 	return addr + (port * 64);
452 }
453 
454 static void vt6421_init_addrs(struct ata_port *ap)
455 {
456 	void __iomem * const * iomap = ap->host->iomap;
457 	void __iomem *reg_addr = iomap[ap->port_no];
458 	void __iomem *bmdma_addr = iomap[4] + (ap->port_no * 8);
459 	struct ata_ioports *ioaddr = &ap->ioaddr;
460 
461 	ioaddr->cmd_addr = reg_addr;
462 	ioaddr->altstatus_addr =
463 	ioaddr->ctl_addr = (void __iomem *)
464 		((unsigned long)(reg_addr + 8) | ATA_PCI_CTL_OFS);
465 	ioaddr->bmdma_addr = bmdma_addr;
466 	ioaddr->scr_addr = vt6421_scr_addr(iomap[5], ap->port_no);
467 
468 	ata_sff_std_ports(ioaddr);
469 
470 	ata_port_pbar_desc(ap, ap->port_no, -1, "port");
471 	ata_port_pbar_desc(ap, 4, ap->port_no * 8, "bmdma");
472 }
473 
474 static int vt6420_prepare_host(struct pci_dev *pdev, struct ata_host **r_host)
475 {
476 	const struct ata_port_info *ppi[] = { &vt6420_port_info, NULL };
477 	struct ata_host *host;
478 	int rc;
479 
480 	if (vt6420_hotplug) {
481 		ppi[0]->port_ops->scr_read = svia_scr_read;
482 		ppi[0]->port_ops->scr_write = svia_scr_write;
483 	}
484 
485 	rc = ata_pci_bmdma_prepare_host(pdev, ppi, &host);
486 	if (rc)
487 		return rc;
488 	*r_host = host;
489 
490 	rc = pcim_iomap_regions(pdev, 1 << 5, DRV_NAME);
491 	if (rc) {
492 		dev_err(&pdev->dev, "failed to iomap PCI BAR 5\n");
493 		return rc;
494 	}
495 
496 	host->ports[0]->ioaddr.scr_addr = svia_scr_addr(host->iomap[5], 0);
497 	host->ports[1]->ioaddr.scr_addr = svia_scr_addr(host->iomap[5], 1);
498 
499 	return 0;
500 }
501 
502 static int vt6421_prepare_host(struct pci_dev *pdev, struct ata_host **r_host)
503 {
504 	const struct ata_port_info *ppi[] =
505 		{ &vt6421_sport_info, &vt6421_sport_info, &vt6421_pport_info };
506 	struct ata_host *host;
507 	int i, rc;
508 
509 	*r_host = host = ata_host_alloc_pinfo(&pdev->dev, ppi, ARRAY_SIZE(ppi));
510 	if (!host) {
511 		dev_err(&pdev->dev, "failed to allocate host\n");
512 		return -ENOMEM;
513 	}
514 
515 	rc = pcim_iomap_regions(pdev, 0x3f, DRV_NAME);
516 	if (rc) {
517 		dev_err(&pdev->dev, "failed to request/iomap PCI BARs (errno=%d)\n",
518 			rc);
519 		return rc;
520 	}
521 	host->iomap = pcim_iomap_table(pdev);
522 
523 	for (i = 0; i < host->n_ports; i++)
524 		vt6421_init_addrs(host->ports[i]);
525 
526 	rc = dma_set_mask(&pdev->dev, ATA_DMA_MASK);
527 	if (rc)
528 		return rc;
529 	rc = dma_set_coherent_mask(&pdev->dev, ATA_DMA_MASK);
530 	if (rc)
531 		return rc;
532 
533 	return 0;
534 }
535 
536 static int vt8251_prepare_host(struct pci_dev *pdev, struct ata_host **r_host)
537 {
538 	const struct ata_port_info *ppi[] = { &vt8251_port_info, NULL };
539 	struct ata_host *host;
540 	int i, rc;
541 
542 	rc = ata_pci_bmdma_prepare_host(pdev, ppi, &host);
543 	if (rc)
544 		return rc;
545 	*r_host = host;
546 
547 	rc = pcim_iomap_regions(pdev, 1 << 5, DRV_NAME);
548 	if (rc) {
549 		dev_err(&pdev->dev, "failed to iomap PCI BAR 5\n");
550 		return rc;
551 	}
552 
553 	/* 8251 hosts four sata ports as M/S of the two channels */
554 	for (i = 0; i < host->n_ports; i++)
555 		ata_slave_link_init(host->ports[i]);
556 
557 	return 0;
558 }
559 
560 static void svia_wd_fix(struct pci_dev *pdev)
561 {
562 	u8 tmp8;
563 
564 	pci_read_config_byte(pdev, 0x52, &tmp8);
565 	pci_write_config_byte(pdev, 0x52, tmp8 | BIT(2));
566 }
567 
568 static irqreturn_t vt642x_interrupt(int irq, void *dev_instance)
569 {
570 	struct ata_host *host = dev_instance;
571 	irqreturn_t rc = ata_bmdma_interrupt(irq, dev_instance);
572 
573 	/* if the IRQ was not handled, it might be a hotplug IRQ */
574 	if (rc != IRQ_HANDLED) {
575 		u32 serror;
576 		unsigned long flags;
577 
578 		spin_lock_irqsave(&host->lock, flags);
579 		/* check for hotplug on port 0 */
580 		svia_scr_read(&host->ports[0]->link, SCR_ERROR, &serror);
581 		if (serror & SERR_PHYRDY_CHG) {
582 			ata_ehi_hotplugged(&host->ports[0]->link.eh_info);
583 			ata_port_freeze(host->ports[0]);
584 			rc = IRQ_HANDLED;
585 		}
586 		/* check for hotplug on port 1 */
587 		svia_scr_read(&host->ports[1]->link, SCR_ERROR, &serror);
588 		if (serror & SERR_PHYRDY_CHG) {
589 			ata_ehi_hotplugged(&host->ports[1]->link.eh_info);
590 			ata_port_freeze(host->ports[1]);
591 			rc = IRQ_HANDLED;
592 		}
593 		spin_unlock_irqrestore(&host->lock, flags);
594 	}
595 
596 	return rc;
597 }
598 
599 static void vt6421_error_handler(struct ata_port *ap)
600 {
601 	struct svia_priv *hpriv = ap->host->private_data;
602 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
603 	u32 serror;
604 
605 	/* see svia_configure() for description */
606 	if (!hpriv->wd_workaround) {
607 		svia_scr_read(&ap->link, SCR_ERROR, &serror);
608 		if (serror == 0x1000500) {
609 			ata_port_warn(ap, "Incompatible drive: enabling workaround. This slows down transfer rate to ~60 MB/s");
610 			svia_wd_fix(pdev);
611 			hpriv->wd_workaround = true;
612 			ap->link.eh_context.i.flags |= ATA_EHI_QUIET;
613 		}
614 	}
615 
616 	ata_sff_error_handler(ap);
617 }
618 
619 static void svia_configure(struct pci_dev *pdev, int board_id,
620 			   struct svia_priv *hpriv)
621 {
622 	u8 tmp8;
623 
624 	pci_read_config_byte(pdev, PCI_INTERRUPT_LINE, &tmp8);
625 	dev_info(&pdev->dev, "routed to hard irq line %d\n",
626 		 (int) (tmp8 & 0xf0) == 0xf0 ? 0 : tmp8 & 0x0f);
627 
628 	/* make sure SATA channels are enabled */
629 	pci_read_config_byte(pdev, SATA_CHAN_ENAB, &tmp8);
630 	if ((tmp8 & ALL_PORTS) != ALL_PORTS) {
631 		dev_dbg(&pdev->dev, "enabling SATA channels (0x%x)\n",
632 			(int)tmp8);
633 		tmp8 |= ALL_PORTS;
634 		pci_write_config_byte(pdev, SATA_CHAN_ENAB, tmp8);
635 	}
636 
637 	/* make sure interrupts for each channel sent to us */
638 	pci_read_config_byte(pdev, SATA_INT_GATE, &tmp8);
639 	if ((tmp8 & ALL_PORTS) != ALL_PORTS) {
640 		dev_dbg(&pdev->dev, "enabling SATA channel interrupts (0x%x)\n",
641 			(int) tmp8);
642 		tmp8 |= ALL_PORTS;
643 		pci_write_config_byte(pdev, SATA_INT_GATE, tmp8);
644 	}
645 
646 	/* make sure native mode is enabled */
647 	pci_read_config_byte(pdev, SATA_NATIVE_MODE, &tmp8);
648 	if ((tmp8 & NATIVE_MODE_ALL) != NATIVE_MODE_ALL) {
649 		dev_dbg(&pdev->dev,
650 			"enabling SATA channel native mode (0x%x)\n",
651 			(int) tmp8);
652 		tmp8 |= NATIVE_MODE_ALL;
653 		pci_write_config_byte(pdev, SATA_NATIVE_MODE, tmp8);
654 	}
655 
656 	if ((board_id == vt6420 && vt6420_hotplug) || board_id == vt6421) {
657 		/* enable IRQ on hotplug */
658 		pci_read_config_byte(pdev, SVIA_MISC_3, &tmp8);
659 		if ((tmp8 & SATA_HOTPLUG) != SATA_HOTPLUG) {
660 			dev_dbg(&pdev->dev,
661 				"enabling SATA hotplug (0x%x)\n",
662 				(int) tmp8);
663 			tmp8 |= SATA_HOTPLUG;
664 			pci_write_config_byte(pdev, SVIA_MISC_3, tmp8);
665 		}
666 	}
667 
668 	/*
669 	 * vt6420/1 has problems talking to some drives.  The following
670 	 * is the fix from Joseph Chan <JosephChan@via.com.tw>.
671 	 *
672 	 * When host issues HOLD, device may send up to 20DW of data
673 	 * before acknowledging it with HOLDA and the host should be
674 	 * able to buffer them in FIFO.  Unfortunately, some WD drives
675 	 * send up to 40DW before acknowledging HOLD and, in the
676 	 * default configuration, this ends up overflowing vt6421's
677 	 * FIFO, making the controller abort the transaction with
678 	 * R_ERR.
679 	 *
680 	 * Rx52[2] is the internal 128DW FIFO Flow control watermark
681 	 * adjusting mechanism enable bit and the default value 0
682 	 * means host will issue HOLD to device when the left FIFO
683 	 * size goes below 32DW.  Setting it to 1 makes the watermark
684 	 * 64DW.
685 	 *
686 	 * https://bugzilla.kernel.org/show_bug.cgi?id=15173
687 	 * http://article.gmane.org/gmane.linux.ide/46352
688 	 * http://thread.gmane.org/gmane.linux.kernel/1062139
689 	 *
690 	 * As the fix slows down data transfer, apply it only if the error
691 	 * actually appears - see vt6421_error_handler()
692 	 * Apply the fix always on vt6420 as we don't know if SCR_ERROR can be
693 	 * read safely.
694 	 */
695 	if (board_id == vt6420) {
696 		svia_wd_fix(pdev);
697 		hpriv->wd_workaround = true;
698 	}
699 }
700 
701 static int svia_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
702 {
703 	unsigned int i;
704 	int rc;
705 	struct ata_host *host = NULL;
706 	int board_id = (int) ent->driver_data;
707 	const unsigned *bar_sizes;
708 	struct svia_priv *hpriv;
709 
710 	ata_print_version_once(&pdev->dev, DRV_VERSION);
711 
712 	rc = pcim_enable_device(pdev);
713 	if (rc)
714 		return rc;
715 
716 	if (board_id == vt6421)
717 		bar_sizes = &vt6421_bar_sizes[0];
718 	else
719 		bar_sizes = &svia_bar_sizes[0];
720 
721 	for (i = 0; i < ARRAY_SIZE(svia_bar_sizes); i++)
722 		if ((pci_resource_start(pdev, i) == 0) ||
723 		    (pci_resource_len(pdev, i) < bar_sizes[i])) {
724 			dev_err(&pdev->dev,
725 				"invalid PCI BAR %u (sz 0x%llx, val 0x%llx)\n",
726 				i,
727 				(unsigned long long)pci_resource_start(pdev, i),
728 				(unsigned long long)pci_resource_len(pdev, i));
729 			return -ENODEV;
730 		}
731 
732 	switch (board_id) {
733 	case vt6420:
734 		rc = vt6420_prepare_host(pdev, &host);
735 		break;
736 	case vt6421:
737 		rc = vt6421_prepare_host(pdev, &host);
738 		break;
739 	case vt8251:
740 		rc = vt8251_prepare_host(pdev, &host);
741 		break;
742 	default:
743 		rc = -EINVAL;
744 	}
745 	if (rc)
746 		return rc;
747 
748 	hpriv = devm_kzalloc(&pdev->dev, sizeof(*hpriv), GFP_KERNEL);
749 	if (!hpriv)
750 		return -ENOMEM;
751 	host->private_data = hpriv;
752 
753 	svia_configure(pdev, board_id, hpriv);
754 
755 	pci_set_master(pdev);
756 	if ((board_id == vt6420 && vt6420_hotplug) || board_id == vt6421)
757 		return ata_host_activate(host, pdev->irq, vt642x_interrupt,
758 					 IRQF_SHARED, &svia_sht);
759 	else
760 		return ata_host_activate(host, pdev->irq, ata_bmdma_interrupt,
761 					 IRQF_SHARED, &svia_sht);
762 }
763 
764 #ifdef CONFIG_PM_SLEEP
765 static int svia_pci_device_resume(struct pci_dev *pdev)
766 {
767 	struct ata_host *host = pci_get_drvdata(pdev);
768 	struct svia_priv *hpriv = host->private_data;
769 	int rc;
770 
771 	rc = ata_pci_device_do_resume(pdev);
772 	if (rc)
773 		return rc;
774 
775 	if (hpriv->wd_workaround)
776 		svia_wd_fix(pdev);
777 	ata_host_resume(host);
778 
779 	return 0;
780 }
781 #endif
782 
783 module_pci_driver(svia_pci_driver);
784