xref: /openbmc/linux/drivers/ata/sata_dwc_460ex.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * drivers/ata/sata_dwc_460ex.c
4  *
5  * Synopsys DesignWare Cores (DWC) SATA host driver
6  *
7  * Author: Mark Miesfeld <mmiesfeld@amcc.com>
8  *
9  * Ported from 2.6.19.2 to 2.6.25/26 by Stefan Roese <sr@denx.de>
10  * Copyright 2008 DENX Software Engineering
11  *
12  * Based on versions provided by AMCC and Synopsys which are:
13  *          Copyright 2006 Applied Micro Circuits Corporation
14  *          COPYRIGHT (C) 2005  SYNOPSYS, INC.  ALL RIGHTS RESERVED
15  */
16 
17 #ifdef CONFIG_SATA_DWC_DEBUG
18 #define DEBUG
19 #endif
20 
21 #ifdef CONFIG_SATA_DWC_VDEBUG
22 #define VERBOSE_DEBUG
23 #define DEBUG_NCQ
24 #endif
25 
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/device.h>
29 #include <linux/dmaengine.h>
30 #include <linux/of_address.h>
31 #include <linux/of_irq.h>
32 #include <linux/of_platform.h>
33 #include <linux/platform_device.h>
34 #include <linux/phy/phy.h>
35 #include <linux/libata.h>
36 #include <linux/slab.h>
37 
38 #include "libata.h"
39 
40 #include <scsi/scsi_host.h>
41 #include <scsi/scsi_cmnd.h>
42 
43 /* These two are defined in "libata.h" */
44 #undef	DRV_NAME
45 #undef	DRV_VERSION
46 
47 #define DRV_NAME        "sata-dwc"
48 #define DRV_VERSION     "1.3"
49 
50 #define sata_dwc_writel(a, v)	writel_relaxed(v, a)
51 #define sata_dwc_readl(a)	readl_relaxed(a)
52 
53 #ifndef NO_IRQ
54 #define NO_IRQ		0
55 #endif
56 
57 #define AHB_DMA_BRST_DFLT	64	/* 16 data items burst length */
58 
59 enum {
60 	SATA_DWC_MAX_PORTS = 1,
61 
62 	SATA_DWC_SCR_OFFSET = 0x24,
63 	SATA_DWC_REG_OFFSET = 0x64,
64 };
65 
66 /* DWC SATA Registers */
67 struct sata_dwc_regs {
68 	u32 fptagr;		/* 1st party DMA tag */
69 	u32 fpbor;		/* 1st party DMA buffer offset */
70 	u32 fptcr;		/* 1st party DMA Xfr count */
71 	u32 dmacr;		/* DMA Control */
72 	u32 dbtsr;		/* DMA Burst Transac size */
73 	u32 intpr;		/* Interrupt Pending */
74 	u32 intmr;		/* Interrupt Mask */
75 	u32 errmr;		/* Error Mask */
76 	u32 llcr;		/* Link Layer Control */
77 	u32 phycr;		/* PHY Control */
78 	u32 physr;		/* PHY Status */
79 	u32 rxbistpd;		/* Recvd BIST pattern def register */
80 	u32 rxbistpd1;		/* Recvd BIST data dword1 */
81 	u32 rxbistpd2;		/* Recvd BIST pattern data dword2 */
82 	u32 txbistpd;		/* Trans BIST pattern def register */
83 	u32 txbistpd1;		/* Trans BIST data dword1 */
84 	u32 txbistpd2;		/* Trans BIST data dword2 */
85 	u32 bistcr;		/* BIST Control Register */
86 	u32 bistfctr;		/* BIST FIS Count Register */
87 	u32 bistsr;		/* BIST Status Register */
88 	u32 bistdecr;		/* BIST Dword Error count register */
89 	u32 res[15];		/* Reserved locations */
90 	u32 testr;		/* Test Register */
91 	u32 versionr;		/* Version Register */
92 	u32 idr;		/* ID Register */
93 	u32 unimpl[192];	/* Unimplemented */
94 	u32 dmadr[256];		/* FIFO Locations in DMA Mode */
95 };
96 
97 enum {
98 	SCR_SCONTROL_DET_ENABLE	=	0x00000001,
99 	SCR_SSTATUS_DET_PRESENT	=	0x00000001,
100 	SCR_SERROR_DIAG_X	=	0x04000000,
101 /* DWC SATA Register Operations */
102 	SATA_DWC_TXFIFO_DEPTH	=	0x01FF,
103 	SATA_DWC_RXFIFO_DEPTH	=	0x01FF,
104 	SATA_DWC_DMACR_TMOD_TXCHEN =	0x00000004,
105 	SATA_DWC_DMACR_TXCHEN	= (0x00000001 | SATA_DWC_DMACR_TMOD_TXCHEN),
106 	SATA_DWC_DMACR_RXCHEN	= (0x00000002 | SATA_DWC_DMACR_TMOD_TXCHEN),
107 	SATA_DWC_DMACR_TXRXCH_CLEAR =	SATA_DWC_DMACR_TMOD_TXCHEN,
108 	SATA_DWC_INTPR_DMAT	=	0x00000001,
109 	SATA_DWC_INTPR_NEWFP	=	0x00000002,
110 	SATA_DWC_INTPR_PMABRT	=	0x00000004,
111 	SATA_DWC_INTPR_ERR	=	0x00000008,
112 	SATA_DWC_INTPR_NEWBIST	=	0x00000010,
113 	SATA_DWC_INTPR_IPF	=	0x10000000,
114 	SATA_DWC_INTMR_DMATM	=	0x00000001,
115 	SATA_DWC_INTMR_NEWFPM	=	0x00000002,
116 	SATA_DWC_INTMR_PMABRTM	=	0x00000004,
117 	SATA_DWC_INTMR_ERRM	=	0x00000008,
118 	SATA_DWC_INTMR_NEWBISTM	=	0x00000010,
119 	SATA_DWC_LLCR_SCRAMEN	=	0x00000001,
120 	SATA_DWC_LLCR_DESCRAMEN	=	0x00000002,
121 	SATA_DWC_LLCR_RPDEN	=	0x00000004,
122 /* This is all error bits, zero's are reserved fields. */
123 	SATA_DWC_SERROR_ERR_BITS =	0x0FFF0F03
124 };
125 
126 #define SATA_DWC_SCR0_SPD_GET(v)	(((v) >> 4) & 0x0000000F)
127 #define SATA_DWC_DMACR_TX_CLEAR(v)	(((v) & ~SATA_DWC_DMACR_TXCHEN) |\
128 						 SATA_DWC_DMACR_TMOD_TXCHEN)
129 #define SATA_DWC_DMACR_RX_CLEAR(v)	(((v) & ~SATA_DWC_DMACR_RXCHEN) |\
130 						 SATA_DWC_DMACR_TMOD_TXCHEN)
131 #define SATA_DWC_DBTSR_MWR(size)	(((size)/4) & SATA_DWC_TXFIFO_DEPTH)
132 #define SATA_DWC_DBTSR_MRD(size)	((((size)/4) & SATA_DWC_RXFIFO_DEPTH)\
133 						 << 16)
134 struct sata_dwc_device {
135 	struct device		*dev;		/* generic device struct */
136 	struct ata_probe_ent	*pe;		/* ptr to probe-ent */
137 	struct ata_host		*host;
138 	struct sata_dwc_regs __iomem *sata_dwc_regs;	/* DW SATA specific */
139 	u32			sactive_issued;
140 	u32			sactive_queued;
141 	struct phy		*phy;
142 	phys_addr_t		dmadr;
143 #ifdef CONFIG_SATA_DWC_OLD_DMA
144 	struct dw_dma_chip	*dma;
145 #endif
146 };
147 
148 #define SATA_DWC_QCMD_MAX	32
149 
150 struct sata_dwc_device_port {
151 	struct sata_dwc_device	*hsdev;
152 	int			cmd_issued[SATA_DWC_QCMD_MAX];
153 	int			dma_pending[SATA_DWC_QCMD_MAX];
154 
155 	/* DMA info */
156 	struct dma_chan			*chan;
157 	struct dma_async_tx_descriptor	*desc[SATA_DWC_QCMD_MAX];
158 	u32				dma_interrupt_count;
159 };
160 
161 /*
162  * Commonly used DWC SATA driver macros
163  */
164 #define HSDEV_FROM_HOST(host)	((struct sata_dwc_device *)(host)->private_data)
165 #define HSDEV_FROM_AP(ap)	((struct sata_dwc_device *)(ap)->host->private_data)
166 #define HSDEVP_FROM_AP(ap)	((struct sata_dwc_device_port *)(ap)->private_data)
167 #define HSDEV_FROM_QC(qc)	((struct sata_dwc_device *)(qc)->ap->host->private_data)
168 #define HSDEV_FROM_HSDEVP(p)	((struct sata_dwc_device *)(p)->hsdev)
169 
170 enum {
171 	SATA_DWC_CMD_ISSUED_NOT		= 0,
172 	SATA_DWC_CMD_ISSUED_PEND	= 1,
173 	SATA_DWC_CMD_ISSUED_EXEC	= 2,
174 	SATA_DWC_CMD_ISSUED_NODATA	= 3,
175 
176 	SATA_DWC_DMA_PENDING_NONE	= 0,
177 	SATA_DWC_DMA_PENDING_TX		= 1,
178 	SATA_DWC_DMA_PENDING_RX		= 2,
179 };
180 
181 /*
182  * Prototypes
183  */
184 static void sata_dwc_bmdma_start_by_tag(struct ata_queued_cmd *qc, u8 tag);
185 static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc,
186 				u32 check_status);
187 static void sata_dwc_dma_xfer_complete(struct ata_port *ap, u32 check_status);
188 static void sata_dwc_port_stop(struct ata_port *ap);
189 static void sata_dwc_clear_dmacr(struct sata_dwc_device_port *hsdevp, u8 tag);
190 
191 #ifdef CONFIG_SATA_DWC_OLD_DMA
192 
193 #include <linux/platform_data/dma-dw.h>
194 #include <linux/dma/dw.h>
195 
196 static struct dw_dma_slave sata_dwc_dma_dws = {
197 	.src_id = 0,
198 	.dst_id = 0,
199 	.m_master = 1,
200 	.p_master = 0,
201 };
202 
203 static bool sata_dwc_dma_filter(struct dma_chan *chan, void *param)
204 {
205 	struct dw_dma_slave *dws = &sata_dwc_dma_dws;
206 
207 	if (dws->dma_dev != chan->device->dev)
208 		return false;
209 
210 	chan->private = dws;
211 	return true;
212 }
213 
214 static int sata_dwc_dma_get_channel_old(struct sata_dwc_device_port *hsdevp)
215 {
216 	struct sata_dwc_device *hsdev = hsdevp->hsdev;
217 	struct dw_dma_slave *dws = &sata_dwc_dma_dws;
218 	dma_cap_mask_t mask;
219 
220 	dws->dma_dev = hsdev->dev;
221 
222 	dma_cap_zero(mask);
223 	dma_cap_set(DMA_SLAVE, mask);
224 
225 	/* Acquire DMA channel */
226 	hsdevp->chan = dma_request_channel(mask, sata_dwc_dma_filter, hsdevp);
227 	if (!hsdevp->chan) {
228 		dev_err(hsdev->dev, "%s: dma channel unavailable\n",
229 			 __func__);
230 		return -EAGAIN;
231 	}
232 
233 	return 0;
234 }
235 
236 static int sata_dwc_dma_init_old(struct platform_device *pdev,
237 				 struct sata_dwc_device *hsdev)
238 {
239 	struct device_node *np = pdev->dev.of_node;
240 	struct resource *res;
241 
242 	hsdev->dma = devm_kzalloc(&pdev->dev, sizeof(*hsdev->dma), GFP_KERNEL);
243 	if (!hsdev->dma)
244 		return -ENOMEM;
245 
246 	hsdev->dma->dev = &pdev->dev;
247 	hsdev->dma->id = pdev->id;
248 
249 	/* Get SATA DMA interrupt number */
250 	hsdev->dma->irq = irq_of_parse_and_map(np, 1);
251 	if (hsdev->dma->irq == NO_IRQ) {
252 		dev_err(&pdev->dev, "no SATA DMA irq\n");
253 		return -ENODEV;
254 	}
255 
256 	/* Get physical SATA DMA register base address */
257 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
258 	hsdev->dma->regs = devm_ioremap_resource(&pdev->dev, res);
259 	if (IS_ERR(hsdev->dma->regs))
260 		return PTR_ERR(hsdev->dma->regs);
261 
262 	/* Initialize AHB DMAC */
263 	return dw_dma_probe(hsdev->dma);
264 }
265 
266 static void sata_dwc_dma_exit_old(struct sata_dwc_device *hsdev)
267 {
268 	if (!hsdev->dma)
269 		return;
270 
271 	dw_dma_remove(hsdev->dma);
272 }
273 
274 #endif
275 
276 static const char *get_prot_descript(u8 protocol)
277 {
278 	switch (protocol) {
279 	case ATA_PROT_NODATA:
280 		return "ATA no data";
281 	case ATA_PROT_PIO:
282 		return "ATA PIO";
283 	case ATA_PROT_DMA:
284 		return "ATA DMA";
285 	case ATA_PROT_NCQ:
286 		return "ATA NCQ";
287 	case ATA_PROT_NCQ_NODATA:
288 		return "ATA NCQ no data";
289 	case ATAPI_PROT_NODATA:
290 		return "ATAPI no data";
291 	case ATAPI_PROT_PIO:
292 		return "ATAPI PIO";
293 	case ATAPI_PROT_DMA:
294 		return "ATAPI DMA";
295 	default:
296 		return "unknown";
297 	}
298 }
299 
300 static const char *get_dma_dir_descript(int dma_dir)
301 {
302 	switch ((enum dma_data_direction)dma_dir) {
303 	case DMA_BIDIRECTIONAL:
304 		return "bidirectional";
305 	case DMA_TO_DEVICE:
306 		return "to device";
307 	case DMA_FROM_DEVICE:
308 		return "from device";
309 	default:
310 		return "none";
311 	}
312 }
313 
314 static void sata_dwc_tf_dump(struct ata_port *ap, struct ata_taskfile *tf)
315 {
316 	dev_vdbg(ap->dev,
317 		"taskfile cmd: 0x%02x protocol: %s flags: 0x%lx device: %x\n",
318 		tf->command, get_prot_descript(tf->protocol), tf->flags,
319 		tf->device);
320 	dev_vdbg(ap->dev,
321 		"feature: 0x%02x nsect: 0x%x lbal: 0x%x lbam: 0x%x lbah: 0x%x\n",
322 		tf->feature, tf->nsect, tf->lbal, tf->lbam, tf->lbah);
323 	dev_vdbg(ap->dev,
324 		"hob_feature: 0x%02x hob_nsect: 0x%x hob_lbal: 0x%x hob_lbam: 0x%x hob_lbah: 0x%x\n",
325 		tf->hob_feature, tf->hob_nsect, tf->hob_lbal, tf->hob_lbam,
326 		tf->hob_lbah);
327 }
328 
329 static void dma_dwc_xfer_done(void *hsdev_instance)
330 {
331 	unsigned long flags;
332 	struct sata_dwc_device *hsdev = hsdev_instance;
333 	struct ata_host *host = (struct ata_host *)hsdev->host;
334 	struct ata_port *ap;
335 	struct sata_dwc_device_port *hsdevp;
336 	u8 tag = 0;
337 	unsigned int port = 0;
338 
339 	spin_lock_irqsave(&host->lock, flags);
340 	ap = host->ports[port];
341 	hsdevp = HSDEVP_FROM_AP(ap);
342 	tag = ap->link.active_tag;
343 
344 	/*
345 	 * Each DMA command produces 2 interrupts.  Only
346 	 * complete the command after both interrupts have been
347 	 * seen. (See sata_dwc_isr())
348 	 */
349 	hsdevp->dma_interrupt_count++;
350 	sata_dwc_clear_dmacr(hsdevp, tag);
351 
352 	if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_NONE) {
353 		dev_err(ap->dev, "DMA not pending tag=0x%02x pending=%d\n",
354 			tag, hsdevp->dma_pending[tag]);
355 	}
356 
357 	if ((hsdevp->dma_interrupt_count % 2) == 0)
358 		sata_dwc_dma_xfer_complete(ap, 1);
359 
360 	spin_unlock_irqrestore(&host->lock, flags);
361 }
362 
363 static struct dma_async_tx_descriptor *dma_dwc_xfer_setup(struct ata_queued_cmd *qc)
364 {
365 	struct ata_port *ap = qc->ap;
366 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
367 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
368 	struct dma_slave_config sconf;
369 	struct dma_async_tx_descriptor *desc;
370 
371 	if (qc->dma_dir == DMA_DEV_TO_MEM) {
372 		sconf.src_addr = hsdev->dmadr;
373 		sconf.device_fc = false;
374 	} else {	/* DMA_MEM_TO_DEV */
375 		sconf.dst_addr = hsdev->dmadr;
376 		sconf.device_fc = false;
377 	}
378 
379 	sconf.direction = qc->dma_dir;
380 	sconf.src_maxburst = AHB_DMA_BRST_DFLT / 4;	/* in items */
381 	sconf.dst_maxburst = AHB_DMA_BRST_DFLT / 4;	/* in items */
382 	sconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
383 	sconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
384 
385 	dmaengine_slave_config(hsdevp->chan, &sconf);
386 
387 	/* Convert SG list to linked list of items (LLIs) for AHB DMA */
388 	desc = dmaengine_prep_slave_sg(hsdevp->chan, qc->sg, qc->n_elem,
389 				       qc->dma_dir,
390 				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
391 
392 	if (!desc)
393 		return NULL;
394 
395 	desc->callback = dma_dwc_xfer_done;
396 	desc->callback_param = hsdev;
397 
398 	dev_dbg(hsdev->dev, "%s sg: 0x%p, count: %d addr: %pa\n", __func__,
399 		qc->sg, qc->n_elem, &hsdev->dmadr);
400 
401 	return desc;
402 }
403 
404 static int sata_dwc_scr_read(struct ata_link *link, unsigned int scr, u32 *val)
405 {
406 	if (scr > SCR_NOTIFICATION) {
407 		dev_err(link->ap->dev, "%s: Incorrect SCR offset 0x%02x\n",
408 			__func__, scr);
409 		return -EINVAL;
410 	}
411 
412 	*val = sata_dwc_readl(link->ap->ioaddr.scr_addr + (scr * 4));
413 	dev_dbg(link->ap->dev, "%s: id=%d reg=%d val=0x%08x\n", __func__,
414 		link->ap->print_id, scr, *val);
415 
416 	return 0;
417 }
418 
419 static int sata_dwc_scr_write(struct ata_link *link, unsigned int scr, u32 val)
420 {
421 	dev_dbg(link->ap->dev, "%s: id=%d reg=%d val=0x%08x\n", __func__,
422 		link->ap->print_id, scr, val);
423 	if (scr > SCR_NOTIFICATION) {
424 		dev_err(link->ap->dev, "%s: Incorrect SCR offset 0x%02x\n",
425 			 __func__, scr);
426 		return -EINVAL;
427 	}
428 	sata_dwc_writel(link->ap->ioaddr.scr_addr + (scr * 4), val);
429 
430 	return 0;
431 }
432 
433 static void clear_serror(struct ata_port *ap)
434 {
435 	u32 val;
436 	sata_dwc_scr_read(&ap->link, SCR_ERROR, &val);
437 	sata_dwc_scr_write(&ap->link, SCR_ERROR, val);
438 }
439 
440 static void clear_interrupt_bit(struct sata_dwc_device *hsdev, u32 bit)
441 {
442 	sata_dwc_writel(&hsdev->sata_dwc_regs->intpr,
443 			sata_dwc_readl(&hsdev->sata_dwc_regs->intpr));
444 }
445 
446 static u32 qcmd_tag_to_mask(u8 tag)
447 {
448 	return 0x00000001 << (tag & 0x1f);
449 }
450 
451 /* See ahci.c */
452 static void sata_dwc_error_intr(struct ata_port *ap,
453 				struct sata_dwc_device *hsdev, uint intpr)
454 {
455 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
456 	struct ata_eh_info *ehi = &ap->link.eh_info;
457 	unsigned int err_mask = 0, action = 0;
458 	struct ata_queued_cmd *qc;
459 	u32 serror;
460 	u8 status, tag;
461 
462 	ata_ehi_clear_desc(ehi);
463 
464 	sata_dwc_scr_read(&ap->link, SCR_ERROR, &serror);
465 	status = ap->ops->sff_check_status(ap);
466 
467 	tag = ap->link.active_tag;
468 
469 	dev_err(ap->dev,
470 		"%s SCR_ERROR=0x%08x intpr=0x%08x status=0x%08x dma_intp=%d pending=%d issued=%d",
471 		__func__, serror, intpr, status, hsdevp->dma_interrupt_count,
472 		hsdevp->dma_pending[tag], hsdevp->cmd_issued[tag]);
473 
474 	/* Clear error register and interrupt bit */
475 	clear_serror(ap);
476 	clear_interrupt_bit(hsdev, SATA_DWC_INTPR_ERR);
477 
478 	/* This is the only error happening now.  TODO check for exact error */
479 
480 	err_mask |= AC_ERR_HOST_BUS;
481 	action |= ATA_EH_RESET;
482 
483 	/* Pass this on to EH */
484 	ehi->serror |= serror;
485 	ehi->action |= action;
486 
487 	qc = ata_qc_from_tag(ap, tag);
488 	if (qc)
489 		qc->err_mask |= err_mask;
490 	else
491 		ehi->err_mask |= err_mask;
492 
493 	ata_port_abort(ap);
494 }
495 
496 /*
497  * Function : sata_dwc_isr
498  * arguments : irq, void *dev_instance, struct pt_regs *regs
499  * Return value : irqreturn_t - status of IRQ
500  * This Interrupt handler called via port ops registered function.
501  * .irq_handler = sata_dwc_isr
502  */
503 static irqreturn_t sata_dwc_isr(int irq, void *dev_instance)
504 {
505 	struct ata_host *host = (struct ata_host *)dev_instance;
506 	struct sata_dwc_device *hsdev = HSDEV_FROM_HOST(host);
507 	struct ata_port *ap;
508 	struct ata_queued_cmd *qc;
509 	unsigned long flags;
510 	u8 status, tag;
511 	int handled, num_processed, port = 0;
512 	uint intpr, sactive, sactive2, tag_mask;
513 	struct sata_dwc_device_port *hsdevp;
514 	hsdev->sactive_issued = 0;
515 
516 	spin_lock_irqsave(&host->lock, flags);
517 
518 	/* Read the interrupt register */
519 	intpr = sata_dwc_readl(&hsdev->sata_dwc_regs->intpr);
520 
521 	ap = host->ports[port];
522 	hsdevp = HSDEVP_FROM_AP(ap);
523 
524 	dev_dbg(ap->dev, "%s intpr=0x%08x active_tag=%d\n", __func__, intpr,
525 		ap->link.active_tag);
526 
527 	/* Check for error interrupt */
528 	if (intpr & SATA_DWC_INTPR_ERR) {
529 		sata_dwc_error_intr(ap, hsdev, intpr);
530 		handled = 1;
531 		goto DONE;
532 	}
533 
534 	/* Check for DMA SETUP FIS (FP DMA) interrupt */
535 	if (intpr & SATA_DWC_INTPR_NEWFP) {
536 		clear_interrupt_bit(hsdev, SATA_DWC_INTPR_NEWFP);
537 
538 		tag = (u8)(sata_dwc_readl(&hsdev->sata_dwc_regs->fptagr));
539 		dev_dbg(ap->dev, "%s: NEWFP tag=%d\n", __func__, tag);
540 		if (hsdevp->cmd_issued[tag] != SATA_DWC_CMD_ISSUED_PEND)
541 			dev_warn(ap->dev, "CMD tag=%d not pending?\n", tag);
542 
543 		hsdev->sactive_issued |= qcmd_tag_to_mask(tag);
544 
545 		qc = ata_qc_from_tag(ap, tag);
546 		if (unlikely(!qc)) {
547 			dev_err(ap->dev, "failed to get qc");
548 			handled = 1;
549 			goto DONE;
550 		}
551 		/*
552 		 * Start FP DMA for NCQ command.  At this point the tag is the
553 		 * active tag.  It is the tag that matches the command about to
554 		 * be completed.
555 		 */
556 		qc->ap->link.active_tag = tag;
557 		sata_dwc_bmdma_start_by_tag(qc, tag);
558 
559 		handled = 1;
560 		goto DONE;
561 	}
562 	sata_dwc_scr_read(&ap->link, SCR_ACTIVE, &sactive);
563 	tag_mask = (hsdev->sactive_issued | sactive) ^ sactive;
564 
565 	/* If no sactive issued and tag_mask is zero then this is not NCQ */
566 	if (hsdev->sactive_issued == 0 && tag_mask == 0) {
567 		if (ap->link.active_tag == ATA_TAG_POISON)
568 			tag = 0;
569 		else
570 			tag = ap->link.active_tag;
571 		qc = ata_qc_from_tag(ap, tag);
572 
573 		/* DEV interrupt w/ no active qc? */
574 		if (unlikely(!qc || (qc->tf.flags & ATA_TFLAG_POLLING))) {
575 			dev_err(ap->dev,
576 				"%s interrupt with no active qc qc=%p\n",
577 				__func__, qc);
578 			ap->ops->sff_check_status(ap);
579 			handled = 1;
580 			goto DONE;
581 		}
582 		status = ap->ops->sff_check_status(ap);
583 
584 		qc->ap->link.active_tag = tag;
585 		hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT;
586 
587 		if (status & ATA_ERR) {
588 			dev_dbg(ap->dev, "interrupt ATA_ERR (0x%x)\n", status);
589 			sata_dwc_qc_complete(ap, qc, 1);
590 			handled = 1;
591 			goto DONE;
592 		}
593 
594 		dev_dbg(ap->dev, "%s non-NCQ cmd interrupt, protocol: %s\n",
595 			__func__, get_prot_descript(qc->tf.protocol));
596 DRVSTILLBUSY:
597 		if (ata_is_dma(qc->tf.protocol)) {
598 			/*
599 			 * Each DMA transaction produces 2 interrupts. The DMAC
600 			 * transfer complete interrupt and the SATA controller
601 			 * operation done interrupt. The command should be
602 			 * completed only after both interrupts are seen.
603 			 */
604 			hsdevp->dma_interrupt_count++;
605 			if (hsdevp->dma_pending[tag] == \
606 					SATA_DWC_DMA_PENDING_NONE) {
607 				dev_err(ap->dev,
608 					"%s: DMA not pending intpr=0x%08x status=0x%08x pending=%d\n",
609 					__func__, intpr, status,
610 					hsdevp->dma_pending[tag]);
611 			}
612 
613 			if ((hsdevp->dma_interrupt_count % 2) == 0)
614 				sata_dwc_dma_xfer_complete(ap, 1);
615 		} else if (ata_is_pio(qc->tf.protocol)) {
616 			ata_sff_hsm_move(ap, qc, status, 0);
617 			handled = 1;
618 			goto DONE;
619 		} else {
620 			if (unlikely(sata_dwc_qc_complete(ap, qc, 1)))
621 				goto DRVSTILLBUSY;
622 		}
623 
624 		handled = 1;
625 		goto DONE;
626 	}
627 
628 	/*
629 	 * This is a NCQ command. At this point we need to figure out for which
630 	 * tags we have gotten a completion interrupt.  One interrupt may serve
631 	 * as completion for more than one operation when commands are queued
632 	 * (NCQ).  We need to process each completed command.
633 	 */
634 
635 	 /* process completed commands */
636 	sata_dwc_scr_read(&ap->link, SCR_ACTIVE, &sactive);
637 	tag_mask = (hsdev->sactive_issued | sactive) ^ sactive;
638 
639 	if (sactive != 0 || hsdev->sactive_issued > 1 || tag_mask > 1) {
640 		dev_dbg(ap->dev,
641 			"%s NCQ:sactive=0x%08x  sactive_issued=0x%08x tag_mask=0x%08x\n",
642 			__func__, sactive, hsdev->sactive_issued, tag_mask);
643 	}
644 
645 	if ((tag_mask | hsdev->sactive_issued) != hsdev->sactive_issued) {
646 		dev_warn(ap->dev,
647 			 "Bad tag mask?  sactive=0x%08x sactive_issued=0x%08x  tag_mask=0x%08x\n",
648 			 sactive, hsdev->sactive_issued, tag_mask);
649 	}
650 
651 	/* read just to clear ... not bad if currently still busy */
652 	status = ap->ops->sff_check_status(ap);
653 	dev_dbg(ap->dev, "%s ATA status register=0x%x\n", __func__, status);
654 
655 	tag = 0;
656 	num_processed = 0;
657 	while (tag_mask) {
658 		num_processed++;
659 		while (!(tag_mask & 0x00000001)) {
660 			tag++;
661 			tag_mask <<= 1;
662 		}
663 
664 		tag_mask &= (~0x00000001);
665 		qc = ata_qc_from_tag(ap, tag);
666 		if (unlikely(!qc)) {
667 			dev_err(ap->dev, "failed to get qc");
668 			handled = 1;
669 			goto DONE;
670 		}
671 
672 		/* To be picked up by completion functions */
673 		qc->ap->link.active_tag = tag;
674 		hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT;
675 
676 		/* Let libata/scsi layers handle error */
677 		if (status & ATA_ERR) {
678 			dev_dbg(ap->dev, "%s ATA_ERR (0x%x)\n", __func__,
679 				status);
680 			sata_dwc_qc_complete(ap, qc, 1);
681 			handled = 1;
682 			goto DONE;
683 		}
684 
685 		/* Process completed command */
686 		dev_dbg(ap->dev, "%s NCQ command, protocol: %s\n", __func__,
687 			get_prot_descript(qc->tf.protocol));
688 		if (ata_is_dma(qc->tf.protocol)) {
689 			hsdevp->dma_interrupt_count++;
690 			if (hsdevp->dma_pending[tag] == \
691 					SATA_DWC_DMA_PENDING_NONE)
692 				dev_warn(ap->dev, "%s: DMA not pending?\n",
693 					__func__);
694 			if ((hsdevp->dma_interrupt_count % 2) == 0)
695 				sata_dwc_dma_xfer_complete(ap, 1);
696 		} else {
697 			if (unlikely(sata_dwc_qc_complete(ap, qc, 1)))
698 				goto STILLBUSY;
699 		}
700 		continue;
701 
702 STILLBUSY:
703 		ap->stats.idle_irq++;
704 		dev_warn(ap->dev, "STILL BUSY IRQ ata%d: irq trap\n",
705 			ap->print_id);
706 	} /* while tag_mask */
707 
708 	/*
709 	 * Check to see if any commands completed while we were processing our
710 	 * initial set of completed commands (read status clears interrupts,
711 	 * so we might miss a completed command interrupt if one came in while
712 	 * we were processing --we read status as part of processing a completed
713 	 * command).
714 	 */
715 	sata_dwc_scr_read(&ap->link, SCR_ACTIVE, &sactive2);
716 	if (sactive2 != sactive) {
717 		dev_dbg(ap->dev,
718 			"More completed - sactive=0x%x sactive2=0x%x\n",
719 			sactive, sactive2);
720 	}
721 	handled = 1;
722 
723 DONE:
724 	spin_unlock_irqrestore(&host->lock, flags);
725 	return IRQ_RETVAL(handled);
726 }
727 
728 static void sata_dwc_clear_dmacr(struct sata_dwc_device_port *hsdevp, u8 tag)
729 {
730 	struct sata_dwc_device *hsdev = HSDEV_FROM_HSDEVP(hsdevp);
731 	u32 dmacr = sata_dwc_readl(&hsdev->sata_dwc_regs->dmacr);
732 
733 	if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_RX) {
734 		dmacr = SATA_DWC_DMACR_RX_CLEAR(dmacr);
735 		sata_dwc_writel(&hsdev->sata_dwc_regs->dmacr, dmacr);
736 	} else if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_TX) {
737 		dmacr = SATA_DWC_DMACR_TX_CLEAR(dmacr);
738 		sata_dwc_writel(&hsdev->sata_dwc_regs->dmacr, dmacr);
739 	} else {
740 		/*
741 		 * This should not happen, it indicates the driver is out of
742 		 * sync.  If it does happen, clear dmacr anyway.
743 		 */
744 		dev_err(hsdev->dev,
745 			"%s DMA protocol RX and TX DMA not pending tag=0x%02x pending=%d dmacr: 0x%08x\n",
746 			__func__, tag, hsdevp->dma_pending[tag], dmacr);
747 		sata_dwc_writel(&hsdev->sata_dwc_regs->dmacr,
748 				SATA_DWC_DMACR_TXRXCH_CLEAR);
749 	}
750 }
751 
752 static void sata_dwc_dma_xfer_complete(struct ata_port *ap, u32 check_status)
753 {
754 	struct ata_queued_cmd *qc;
755 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
756 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
757 	u8 tag = 0;
758 
759 	tag = ap->link.active_tag;
760 	qc = ata_qc_from_tag(ap, tag);
761 	if (!qc) {
762 		dev_err(ap->dev, "failed to get qc");
763 		return;
764 	}
765 
766 #ifdef DEBUG_NCQ
767 	if (tag > 0) {
768 		dev_info(ap->dev,
769 			 "%s tag=%u cmd=0x%02x dma dir=%s proto=%s dmacr=0x%08x\n",
770 			 __func__, qc->hw_tag, qc->tf.command,
771 			 get_dma_dir_descript(qc->dma_dir),
772 			 get_prot_descript(qc->tf.protocol),
773 			 sata_dwc_readl(&hsdev->sata_dwc_regs->dmacr));
774 	}
775 #endif
776 
777 	if (ata_is_dma(qc->tf.protocol)) {
778 		if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_NONE) {
779 			dev_err(ap->dev,
780 				"%s DMA protocol RX and TX DMA not pending dmacr: 0x%08x\n",
781 				__func__,
782 				sata_dwc_readl(&hsdev->sata_dwc_regs->dmacr));
783 		}
784 
785 		hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_NONE;
786 		sata_dwc_qc_complete(ap, qc, check_status);
787 		ap->link.active_tag = ATA_TAG_POISON;
788 	} else {
789 		sata_dwc_qc_complete(ap, qc, check_status);
790 	}
791 }
792 
793 static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc,
794 				u32 check_status)
795 {
796 	u8 status = 0;
797 	u32 mask = 0x0;
798 	u8 tag = qc->hw_tag;
799 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
800 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
801 	hsdev->sactive_queued = 0;
802 	dev_dbg(ap->dev, "%s checkstatus? %x\n", __func__, check_status);
803 
804 	if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_TX)
805 		dev_err(ap->dev, "TX DMA PENDING\n");
806 	else if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_RX)
807 		dev_err(ap->dev, "RX DMA PENDING\n");
808 	dev_dbg(ap->dev,
809 		"QC complete cmd=0x%02x status=0x%02x ata%u: protocol=%d\n",
810 		qc->tf.command, status, ap->print_id, qc->tf.protocol);
811 
812 	/* clear active bit */
813 	mask = (~(qcmd_tag_to_mask(tag)));
814 	hsdev->sactive_queued = hsdev->sactive_queued & mask;
815 	hsdev->sactive_issued = hsdev->sactive_issued & mask;
816 	ata_qc_complete(qc);
817 	return 0;
818 }
819 
820 static void sata_dwc_enable_interrupts(struct sata_dwc_device *hsdev)
821 {
822 	/* Enable selective interrupts by setting the interrupt maskregister*/
823 	sata_dwc_writel(&hsdev->sata_dwc_regs->intmr,
824 			SATA_DWC_INTMR_ERRM |
825 			SATA_DWC_INTMR_NEWFPM |
826 			SATA_DWC_INTMR_PMABRTM |
827 			SATA_DWC_INTMR_DMATM);
828 	/*
829 	 * Unmask the error bits that should trigger an error interrupt by
830 	 * setting the error mask register.
831 	 */
832 	sata_dwc_writel(&hsdev->sata_dwc_regs->errmr, SATA_DWC_SERROR_ERR_BITS);
833 
834 	dev_dbg(hsdev->dev, "%s: INTMR = 0x%08x, ERRMR = 0x%08x\n",
835 		 __func__, sata_dwc_readl(&hsdev->sata_dwc_regs->intmr),
836 		sata_dwc_readl(&hsdev->sata_dwc_regs->errmr));
837 }
838 
839 static void sata_dwc_setup_port(struct ata_ioports *port, void __iomem *base)
840 {
841 	port->cmd_addr		= base + 0x00;
842 	port->data_addr		= base + 0x00;
843 
844 	port->error_addr	= base + 0x04;
845 	port->feature_addr	= base + 0x04;
846 
847 	port->nsect_addr	= base + 0x08;
848 
849 	port->lbal_addr		= base + 0x0c;
850 	port->lbam_addr		= base + 0x10;
851 	port->lbah_addr		= base + 0x14;
852 
853 	port->device_addr	= base + 0x18;
854 	port->command_addr	= base + 0x1c;
855 	port->status_addr	= base + 0x1c;
856 
857 	port->altstatus_addr	= base + 0x20;
858 	port->ctl_addr		= base + 0x20;
859 }
860 
861 static int sata_dwc_dma_get_channel(struct sata_dwc_device_port *hsdevp)
862 {
863 	struct sata_dwc_device *hsdev = hsdevp->hsdev;
864 	struct device *dev = hsdev->dev;
865 
866 #ifdef CONFIG_SATA_DWC_OLD_DMA
867 	if (!of_find_property(dev->of_node, "dmas", NULL))
868 		return sata_dwc_dma_get_channel_old(hsdevp);
869 #endif
870 
871 	hsdevp->chan = dma_request_chan(dev, "sata-dma");
872 	if (IS_ERR(hsdevp->chan)) {
873 		dev_err(dev, "failed to allocate dma channel: %ld\n",
874 			PTR_ERR(hsdevp->chan));
875 		return PTR_ERR(hsdevp->chan);
876 	}
877 
878 	return 0;
879 }
880 
881 /*
882  * Function : sata_dwc_port_start
883  * arguments : struct ata_ioports *port
884  * Return value : returns 0 if success, error code otherwise
885  * This function allocates the scatter gather LLI table for AHB DMA
886  */
887 static int sata_dwc_port_start(struct ata_port *ap)
888 {
889 	int err = 0;
890 	struct sata_dwc_device *hsdev;
891 	struct sata_dwc_device_port *hsdevp = NULL;
892 	struct device *pdev;
893 	int i;
894 
895 	hsdev = HSDEV_FROM_AP(ap);
896 
897 	dev_dbg(ap->dev, "%s: port_no=%d\n", __func__, ap->port_no);
898 
899 	hsdev->host = ap->host;
900 	pdev = ap->host->dev;
901 	if (!pdev) {
902 		dev_err(ap->dev, "%s: no ap->host->dev\n", __func__);
903 		err = -ENODEV;
904 		goto CLEANUP;
905 	}
906 
907 	/* Allocate Port Struct */
908 	hsdevp = kzalloc(sizeof(*hsdevp), GFP_KERNEL);
909 	if (!hsdevp) {
910 		err = -ENOMEM;
911 		goto CLEANUP;
912 	}
913 	hsdevp->hsdev = hsdev;
914 
915 	err = sata_dwc_dma_get_channel(hsdevp);
916 	if (err)
917 		goto CLEANUP_ALLOC;
918 
919 	err = phy_power_on(hsdev->phy);
920 	if (err)
921 		goto CLEANUP_ALLOC;
922 
923 	for (i = 0; i < SATA_DWC_QCMD_MAX; i++)
924 		hsdevp->cmd_issued[i] = SATA_DWC_CMD_ISSUED_NOT;
925 
926 	ap->bmdma_prd = NULL;	/* set these so libata doesn't use them */
927 	ap->bmdma_prd_dma = 0;
928 
929 	if (ap->port_no == 0)  {
930 		dev_dbg(ap->dev, "%s: clearing TXCHEN, RXCHEN in DMAC\n",
931 			__func__);
932 		sata_dwc_writel(&hsdev->sata_dwc_regs->dmacr,
933 				SATA_DWC_DMACR_TXRXCH_CLEAR);
934 
935 		dev_dbg(ap->dev, "%s: setting burst size in DBTSR\n",
936 			 __func__);
937 		sata_dwc_writel(&hsdev->sata_dwc_regs->dbtsr,
938 				(SATA_DWC_DBTSR_MWR(AHB_DMA_BRST_DFLT) |
939 				 SATA_DWC_DBTSR_MRD(AHB_DMA_BRST_DFLT)));
940 	}
941 
942 	/* Clear any error bits before libata starts issuing commands */
943 	clear_serror(ap);
944 	ap->private_data = hsdevp;
945 	dev_dbg(ap->dev, "%s: done\n", __func__);
946 	return 0;
947 
948 CLEANUP_ALLOC:
949 	kfree(hsdevp);
950 CLEANUP:
951 	dev_dbg(ap->dev, "%s: fail. ap->id = %d\n", __func__, ap->print_id);
952 	return err;
953 }
954 
955 static void sata_dwc_port_stop(struct ata_port *ap)
956 {
957 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
958 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
959 
960 	dev_dbg(ap->dev, "%s: ap->id = %d\n", __func__, ap->print_id);
961 
962 	dmaengine_terminate_sync(hsdevp->chan);
963 	dma_release_channel(hsdevp->chan);
964 	phy_power_off(hsdev->phy);
965 
966 	kfree(hsdevp);
967 	ap->private_data = NULL;
968 }
969 
970 /*
971  * Function : sata_dwc_exec_command_by_tag
972  * arguments : ata_port *ap, ata_taskfile *tf, u8 tag, u32 cmd_issued
973  * Return value : None
974  * This function keeps track of individual command tag ids and calls
975  * ata_exec_command in libata
976  */
977 static void sata_dwc_exec_command_by_tag(struct ata_port *ap,
978 					 struct ata_taskfile *tf,
979 					 u8 tag, u32 cmd_issued)
980 {
981 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
982 
983 	dev_dbg(ap->dev, "%s cmd(0x%02x): %s tag=%d\n", __func__, tf->command,
984 		ata_get_cmd_descript(tf->command), tag);
985 
986 	hsdevp->cmd_issued[tag] = cmd_issued;
987 
988 	/*
989 	 * Clear SError before executing a new command.
990 	 * sata_dwc_scr_write and read can not be used here. Clearing the PM
991 	 * managed SError register for the disk needs to be done before the
992 	 * task file is loaded.
993 	 */
994 	clear_serror(ap);
995 	ata_sff_exec_command(ap, tf);
996 }
997 
998 static void sata_dwc_bmdma_setup_by_tag(struct ata_queued_cmd *qc, u8 tag)
999 {
1000 	sata_dwc_exec_command_by_tag(qc->ap, &qc->tf, tag,
1001 				     SATA_DWC_CMD_ISSUED_PEND);
1002 }
1003 
1004 static void sata_dwc_bmdma_setup(struct ata_queued_cmd *qc)
1005 {
1006 	u8 tag = qc->hw_tag;
1007 
1008 	if (ata_is_ncq(qc->tf.protocol)) {
1009 		dev_dbg(qc->ap->dev, "%s: ap->link.sactive=0x%08x tag=%d\n",
1010 			__func__, qc->ap->link.sactive, tag);
1011 	} else {
1012 		tag = 0;
1013 	}
1014 	sata_dwc_bmdma_setup_by_tag(qc, tag);
1015 }
1016 
1017 static void sata_dwc_bmdma_start_by_tag(struct ata_queued_cmd *qc, u8 tag)
1018 {
1019 	int start_dma;
1020 	u32 reg;
1021 	struct sata_dwc_device *hsdev = HSDEV_FROM_QC(qc);
1022 	struct ata_port *ap = qc->ap;
1023 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1024 	struct dma_async_tx_descriptor *desc = hsdevp->desc[tag];
1025 	int dir = qc->dma_dir;
1026 
1027 	if (hsdevp->cmd_issued[tag] != SATA_DWC_CMD_ISSUED_NOT) {
1028 		start_dma = 1;
1029 		if (dir == DMA_TO_DEVICE)
1030 			hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_TX;
1031 		else
1032 			hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_RX;
1033 	} else {
1034 		dev_err(ap->dev,
1035 			"%s: Command not pending cmd_issued=%d (tag=%d) DMA NOT started\n",
1036 			__func__, hsdevp->cmd_issued[tag], tag);
1037 		start_dma = 0;
1038 	}
1039 
1040 	dev_dbg(ap->dev,
1041 		"%s qc=%p tag: %x cmd: 0x%02x dma_dir: %s start_dma? %x\n",
1042 		__func__, qc, tag, qc->tf.command,
1043 		get_dma_dir_descript(qc->dma_dir), start_dma);
1044 	sata_dwc_tf_dump(ap, &qc->tf);
1045 
1046 	if (start_dma) {
1047 		sata_dwc_scr_read(&ap->link, SCR_ERROR, &reg);
1048 		if (reg & SATA_DWC_SERROR_ERR_BITS) {
1049 			dev_err(ap->dev, "%s: ****** SError=0x%08x ******\n",
1050 				__func__, reg);
1051 		}
1052 
1053 		if (dir == DMA_TO_DEVICE)
1054 			sata_dwc_writel(&hsdev->sata_dwc_regs->dmacr,
1055 					SATA_DWC_DMACR_TXCHEN);
1056 		else
1057 			sata_dwc_writel(&hsdev->sata_dwc_regs->dmacr,
1058 					SATA_DWC_DMACR_RXCHEN);
1059 
1060 		/* Enable AHB DMA transfer on the specified channel */
1061 		dmaengine_submit(desc);
1062 		dma_async_issue_pending(hsdevp->chan);
1063 	}
1064 }
1065 
1066 static void sata_dwc_bmdma_start(struct ata_queued_cmd *qc)
1067 {
1068 	u8 tag = qc->hw_tag;
1069 
1070 	if (ata_is_ncq(qc->tf.protocol)) {
1071 		dev_dbg(qc->ap->dev, "%s: ap->link.sactive=0x%08x tag=%d\n",
1072 			__func__, qc->ap->link.sactive, tag);
1073 	} else {
1074 		tag = 0;
1075 	}
1076 	dev_dbg(qc->ap->dev, "%s\n", __func__);
1077 	sata_dwc_bmdma_start_by_tag(qc, tag);
1078 }
1079 
1080 static unsigned int sata_dwc_qc_issue(struct ata_queued_cmd *qc)
1081 {
1082 	u32 sactive;
1083 	u8 tag = qc->hw_tag;
1084 	struct ata_port *ap = qc->ap;
1085 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1086 
1087 #ifdef DEBUG_NCQ
1088 	if (qc->hw_tag > 0 || ap->link.sactive > 1)
1089 		dev_info(ap->dev,
1090 			 "%s ap id=%d cmd(0x%02x)=%s qc tag=%d prot=%s ap active_tag=0x%08x ap sactive=0x%08x\n",
1091 			 __func__, ap->print_id, qc->tf.command,
1092 			 ata_get_cmd_descript(qc->tf.command),
1093 			 qc->hw_tag, get_prot_descript(qc->tf.protocol),
1094 			 ap->link.active_tag, ap->link.sactive);
1095 #endif
1096 
1097 	if (!ata_is_ncq(qc->tf.protocol))
1098 		tag = 0;
1099 
1100 	if (ata_is_dma(qc->tf.protocol)) {
1101 		hsdevp->desc[tag] = dma_dwc_xfer_setup(qc);
1102 		if (!hsdevp->desc[tag])
1103 			return AC_ERR_SYSTEM;
1104 	} else {
1105 		hsdevp->desc[tag] = NULL;
1106 	}
1107 
1108 	if (ata_is_ncq(qc->tf.protocol)) {
1109 		sata_dwc_scr_read(&ap->link, SCR_ACTIVE, &sactive);
1110 		sactive |= (0x00000001 << tag);
1111 		sata_dwc_scr_write(&ap->link, SCR_ACTIVE, sactive);
1112 
1113 		dev_dbg(qc->ap->dev,
1114 			"%s: tag=%d ap->link.sactive = 0x%08x sactive=0x%08x\n",
1115 			__func__, tag, qc->ap->link.sactive, sactive);
1116 
1117 		ap->ops->sff_tf_load(ap, &qc->tf);
1118 		sata_dwc_exec_command_by_tag(ap, &qc->tf, tag,
1119 					     SATA_DWC_CMD_ISSUED_PEND);
1120 	} else {
1121 		return ata_bmdma_qc_issue(qc);
1122 	}
1123 	return 0;
1124 }
1125 
1126 static void sata_dwc_error_handler(struct ata_port *ap)
1127 {
1128 	ata_sff_error_handler(ap);
1129 }
1130 
1131 static int sata_dwc_hardreset(struct ata_link *link, unsigned int *class,
1132 			      unsigned long deadline)
1133 {
1134 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(link->ap);
1135 	int ret;
1136 
1137 	ret = sata_sff_hardreset(link, class, deadline);
1138 
1139 	sata_dwc_enable_interrupts(hsdev);
1140 
1141 	/* Reconfigure the DMA control register */
1142 	sata_dwc_writel(&hsdev->sata_dwc_regs->dmacr,
1143 			SATA_DWC_DMACR_TXRXCH_CLEAR);
1144 
1145 	/* Reconfigure the DMA Burst Transaction Size register */
1146 	sata_dwc_writel(&hsdev->sata_dwc_regs->dbtsr,
1147 			SATA_DWC_DBTSR_MWR(AHB_DMA_BRST_DFLT) |
1148 			SATA_DWC_DBTSR_MRD(AHB_DMA_BRST_DFLT));
1149 
1150 	return ret;
1151 }
1152 
1153 static void sata_dwc_dev_select(struct ata_port *ap, unsigned int device)
1154 {
1155 	/* SATA DWC is master only */
1156 }
1157 
1158 /*
1159  * scsi mid-layer and libata interface structures
1160  */
1161 static struct scsi_host_template sata_dwc_sht = {
1162 	ATA_NCQ_SHT(DRV_NAME),
1163 	/*
1164 	 * test-only: Currently this driver doesn't handle NCQ
1165 	 * correctly. We enable NCQ but set the queue depth to a
1166 	 * max of 1. This will get fixed in in a future release.
1167 	 */
1168 	.sg_tablesize		= LIBATA_MAX_PRD,
1169 	/* .can_queue		= ATA_MAX_QUEUE, */
1170 	/*
1171 	 * Make sure a LLI block is not created that will span 8K max FIS
1172 	 * boundary. If the block spans such a FIS boundary, there is a chance
1173 	 * that a DMA burst will cross that boundary -- this results in an
1174 	 * error in the host controller.
1175 	 */
1176 	.dma_boundary		= 0x1fff /* ATA_DMA_BOUNDARY */,
1177 };
1178 
1179 static struct ata_port_operations sata_dwc_ops = {
1180 	.inherits		= &ata_sff_port_ops,
1181 
1182 	.error_handler		= sata_dwc_error_handler,
1183 	.hardreset		= sata_dwc_hardreset,
1184 
1185 	.qc_issue		= sata_dwc_qc_issue,
1186 
1187 	.scr_read		= sata_dwc_scr_read,
1188 	.scr_write		= sata_dwc_scr_write,
1189 
1190 	.port_start		= sata_dwc_port_start,
1191 	.port_stop		= sata_dwc_port_stop,
1192 
1193 	.sff_dev_select		= sata_dwc_dev_select,
1194 
1195 	.bmdma_setup		= sata_dwc_bmdma_setup,
1196 	.bmdma_start		= sata_dwc_bmdma_start,
1197 };
1198 
1199 static const struct ata_port_info sata_dwc_port_info[] = {
1200 	{
1201 		.flags		= ATA_FLAG_SATA | ATA_FLAG_NCQ,
1202 		.pio_mask	= ATA_PIO4,
1203 		.udma_mask	= ATA_UDMA6,
1204 		.port_ops	= &sata_dwc_ops,
1205 	},
1206 };
1207 
1208 static int sata_dwc_probe(struct platform_device *ofdev)
1209 {
1210 	struct sata_dwc_device *hsdev;
1211 	u32 idr, versionr;
1212 	char *ver = (char *)&versionr;
1213 	void __iomem *base;
1214 	int err = 0;
1215 	int irq;
1216 	struct ata_host *host;
1217 	struct ata_port_info pi = sata_dwc_port_info[0];
1218 	const struct ata_port_info *ppi[] = { &pi, NULL };
1219 	struct device_node *np = ofdev->dev.of_node;
1220 	struct resource *res;
1221 
1222 	/* Allocate DWC SATA device */
1223 	host = ata_host_alloc_pinfo(&ofdev->dev, ppi, SATA_DWC_MAX_PORTS);
1224 	hsdev = devm_kzalloc(&ofdev->dev, sizeof(*hsdev), GFP_KERNEL);
1225 	if (!host || !hsdev)
1226 		return -ENOMEM;
1227 
1228 	host->private_data = hsdev;
1229 
1230 	/* Ioremap SATA registers */
1231 	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
1232 	base = devm_ioremap_resource(&ofdev->dev, res);
1233 	if (IS_ERR(base))
1234 		return PTR_ERR(base);
1235 	dev_dbg(&ofdev->dev, "ioremap done for SATA register address\n");
1236 
1237 	/* Synopsys DWC SATA specific Registers */
1238 	hsdev->sata_dwc_regs = base + SATA_DWC_REG_OFFSET;
1239 	hsdev->dmadr = res->start + SATA_DWC_REG_OFFSET + offsetof(struct sata_dwc_regs, dmadr);
1240 
1241 	/* Setup port */
1242 	host->ports[0]->ioaddr.cmd_addr = base;
1243 	host->ports[0]->ioaddr.scr_addr = base + SATA_DWC_SCR_OFFSET;
1244 	sata_dwc_setup_port(&host->ports[0]->ioaddr, base);
1245 
1246 	/* Read the ID and Version Registers */
1247 	idr = sata_dwc_readl(&hsdev->sata_dwc_regs->idr);
1248 	versionr = sata_dwc_readl(&hsdev->sata_dwc_regs->versionr);
1249 	dev_notice(&ofdev->dev, "id %d, controller version %c.%c%c\n",
1250 		   idr, ver[0], ver[1], ver[2]);
1251 
1252 	/* Save dev for later use in dev_xxx() routines */
1253 	hsdev->dev = &ofdev->dev;
1254 
1255 	/* Enable SATA Interrupts */
1256 	sata_dwc_enable_interrupts(hsdev);
1257 
1258 	/* Get SATA interrupt number */
1259 	irq = irq_of_parse_and_map(np, 0);
1260 	if (irq == NO_IRQ) {
1261 		dev_err(&ofdev->dev, "no SATA DMA irq\n");
1262 		return -ENODEV;
1263 	}
1264 
1265 #ifdef CONFIG_SATA_DWC_OLD_DMA
1266 	if (!of_find_property(np, "dmas", NULL)) {
1267 		err = sata_dwc_dma_init_old(ofdev, hsdev);
1268 		if (err)
1269 			return err;
1270 	}
1271 #endif
1272 
1273 	hsdev->phy = devm_phy_optional_get(hsdev->dev, "sata-phy");
1274 	if (IS_ERR(hsdev->phy))
1275 		return PTR_ERR(hsdev->phy);
1276 
1277 	err = phy_init(hsdev->phy);
1278 	if (err)
1279 		goto error_out;
1280 
1281 	/*
1282 	 * Now, register with libATA core, this will also initiate the
1283 	 * device discovery process, invoking our port_start() handler &
1284 	 * error_handler() to execute a dummy Softreset EH session
1285 	 */
1286 	err = ata_host_activate(host, irq, sata_dwc_isr, 0, &sata_dwc_sht);
1287 	if (err)
1288 		dev_err(&ofdev->dev, "failed to activate host");
1289 
1290 	return 0;
1291 
1292 error_out:
1293 	phy_exit(hsdev->phy);
1294 	return err;
1295 }
1296 
1297 static int sata_dwc_remove(struct platform_device *ofdev)
1298 {
1299 	struct device *dev = &ofdev->dev;
1300 	struct ata_host *host = dev_get_drvdata(dev);
1301 	struct sata_dwc_device *hsdev = host->private_data;
1302 
1303 	ata_host_detach(host);
1304 
1305 	phy_exit(hsdev->phy);
1306 
1307 #ifdef CONFIG_SATA_DWC_OLD_DMA
1308 	/* Free SATA DMA resources */
1309 	sata_dwc_dma_exit_old(hsdev);
1310 #endif
1311 
1312 	dev_dbg(&ofdev->dev, "done\n");
1313 	return 0;
1314 }
1315 
1316 static const struct of_device_id sata_dwc_match[] = {
1317 	{ .compatible = "amcc,sata-460ex", },
1318 	{}
1319 };
1320 MODULE_DEVICE_TABLE(of, sata_dwc_match);
1321 
1322 static struct platform_driver sata_dwc_driver = {
1323 	.driver = {
1324 		.name = DRV_NAME,
1325 		.of_match_table = sata_dwc_match,
1326 	},
1327 	.probe = sata_dwc_probe,
1328 	.remove = sata_dwc_remove,
1329 };
1330 
1331 module_platform_driver(sata_dwc_driver);
1332 
1333 MODULE_LICENSE("GPL");
1334 MODULE_AUTHOR("Mark Miesfeld <mmiesfeld@amcc.com>");
1335 MODULE_DESCRIPTION("DesignWare Cores SATA controller low level driver");
1336 MODULE_VERSION(DRV_VERSION);
1337