xref: /openbmc/linux/drivers/ata/sata_dwc_460ex.c (revision 95e9fd10)
1 /*
2  * drivers/ata/sata_dwc_460ex.c
3  *
4  * Synopsys DesignWare Cores (DWC) SATA host driver
5  *
6  * Author: Mark Miesfeld <mmiesfeld@amcc.com>
7  *
8  * Ported from 2.6.19.2 to 2.6.25/26 by Stefan Roese <sr@denx.de>
9  * Copyright 2008 DENX Software Engineering
10  *
11  * Based on versions provided by AMCC and Synopsys which are:
12  *          Copyright 2006 Applied Micro Circuits Corporation
13  *          COPYRIGHT (C) 2005  SYNOPSYS, INC.  ALL RIGHTS RESERVED
14  *
15  * This program is free software; you can redistribute  it and/or modify it
16  * under  the terms of  the GNU General  Public License as published by the
17  * Free Software Foundation;  either version 2 of the  License, or (at your
18  * option) any later version.
19  */
20 
21 #ifdef CONFIG_SATA_DWC_DEBUG
22 #define DEBUG
23 #endif
24 
25 #ifdef CONFIG_SATA_DWC_VDEBUG
26 #define VERBOSE_DEBUG
27 #define DEBUG_NCQ
28 #endif
29 
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/init.h>
33 #include <linux/device.h>
34 #include <linux/of_platform.h>
35 #include <linux/platform_device.h>
36 #include <linux/libata.h>
37 #include <linux/slab.h>
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 #define DRV_NAME        "sata-dwc"
47 #define DRV_VERSION     "1.3"
48 
49 /* SATA DMA driver Globals */
50 #define DMA_NUM_CHANS		1
51 #define DMA_NUM_CHAN_REGS	8
52 
53 /* SATA DMA Register definitions */
54 #define AHB_DMA_BRST_DFLT	64	/* 16 data items burst length*/
55 
56 struct dmareg {
57 	u32 low;		/* Low bits 0-31 */
58 	u32 high;		/* High bits 32-63 */
59 };
60 
61 /* DMA Per Channel registers */
62 struct dma_chan_regs {
63 	struct dmareg sar;	/* Source Address */
64 	struct dmareg dar;	/* Destination address */
65 	struct dmareg llp;	/* Linked List Pointer */
66 	struct dmareg ctl;	/* Control */
67 	struct dmareg sstat;	/* Source Status not implemented in core */
68 	struct dmareg dstat;	/* Destination Status not implemented in core*/
69 	struct dmareg sstatar;	/* Source Status Address not impl in core */
70 	struct dmareg dstatar;	/* Destination Status Address not implemente */
71 	struct dmareg cfg;	/* Config */
72 	struct dmareg sgr;	/* Source Gather */
73 	struct dmareg dsr;	/* Destination Scatter */
74 };
75 
76 /* Generic Interrupt Registers */
77 struct dma_interrupt_regs {
78 	struct dmareg tfr;	/* Transfer Interrupt */
79 	struct dmareg block;	/* Block Interrupt */
80 	struct dmareg srctran;	/* Source Transfer Interrupt */
81 	struct dmareg dsttran;	/* Dest Transfer Interrupt */
82 	struct dmareg error;	/* Error */
83 };
84 
85 struct ahb_dma_regs {
86 	struct dma_chan_regs	chan_regs[DMA_NUM_CHAN_REGS];
87 	struct dma_interrupt_regs interrupt_raw;	/* Raw Interrupt */
88 	struct dma_interrupt_regs interrupt_status;	/* Interrupt Status */
89 	struct dma_interrupt_regs interrupt_mask;	/* Interrupt Mask */
90 	struct dma_interrupt_regs interrupt_clear;	/* Interrupt Clear */
91 	struct dmareg		statusInt;	/* Interrupt combined*/
92 	struct dmareg		rq_srcreg;	/* Src Trans Req */
93 	struct dmareg		rq_dstreg;	/* Dst Trans Req */
94 	struct dmareg		rq_sgl_srcreg;	/* Sngl Src Trans Req*/
95 	struct dmareg		rq_sgl_dstreg;	/* Sngl Dst Trans Req*/
96 	struct dmareg		rq_lst_srcreg;	/* Last Src Trans Req*/
97 	struct dmareg		rq_lst_dstreg;	/* Last Dst Trans Req*/
98 	struct dmareg		dma_cfg;		/* DMA Config */
99 	struct dmareg		dma_chan_en;		/* DMA Channel Enable*/
100 	struct dmareg		dma_id;			/* DMA ID */
101 	struct dmareg		dma_test;		/* DMA Test */
102 	struct dmareg		res1;			/* reserved */
103 	struct dmareg		res2;			/* reserved */
104 	/*
105 	 * DMA Comp Params
106 	 * Param 6 = dma_param[0], Param 5 = dma_param[1],
107 	 * Param 4 = dma_param[2] ...
108 	 */
109 	struct dmareg		dma_params[6];
110 };
111 
112 /* Data structure for linked list item */
113 struct lli {
114 	u32		sar;		/* Source Address */
115 	u32		dar;		/* Destination address */
116 	u32		llp;		/* Linked List Pointer */
117 	struct dmareg	ctl;		/* Control */
118 	struct dmareg	dstat;		/* Destination Status */
119 };
120 
121 enum {
122 	SATA_DWC_DMAC_LLI_SZ =	(sizeof(struct lli)),
123 	SATA_DWC_DMAC_LLI_NUM =	256,
124 	SATA_DWC_DMAC_LLI_TBL_SZ = (SATA_DWC_DMAC_LLI_SZ * \
125 					SATA_DWC_DMAC_LLI_NUM),
126 	SATA_DWC_DMAC_TWIDTH_BYTES = 4,
127 	SATA_DWC_DMAC_CTRL_TSIZE_MAX = (0x00000800 * \
128 						SATA_DWC_DMAC_TWIDTH_BYTES),
129 };
130 
131 /* DMA Register Operation Bits */
132 enum {
133 	DMA_EN	=		0x00000001, /* Enable AHB DMA */
134 	DMA_CTL_LLP_SRCEN =	0x10000000, /* Blk chain enable Src */
135 	DMA_CTL_LLP_DSTEN =	0x08000000, /* Blk chain enable Dst */
136 };
137 
138 #define	DMA_CTL_BLK_TS(size)	((size) & 0x000000FFF)	/* Blk Transfer size */
139 #define DMA_CHANNEL(ch)		(0x00000001 << (ch))	/* Select channel */
140 	/* Enable channel */
141 #define	DMA_ENABLE_CHAN(ch)	((0x00000001 << (ch)) |			\
142 				 ((0x000000001 << (ch)) << 8))
143 	/* Disable channel */
144 #define	DMA_DISABLE_CHAN(ch)	(0x00000000 | ((0x000000001 << (ch)) << 8))
145 	/* Transfer Type & Flow Controller */
146 #define	DMA_CTL_TTFC(type)	(((type) & 0x7) << 20)
147 #define	DMA_CTL_SMS(num)	(((num) & 0x3) << 25) /* Src Master Select */
148 #define	DMA_CTL_DMS(num)	(((num) & 0x3) << 23)/* Dst Master Select */
149 	/* Src Burst Transaction Length */
150 #define DMA_CTL_SRC_MSIZE(size) (((size) & 0x7) << 14)
151 	/* Dst Burst Transaction Length */
152 #define	DMA_CTL_DST_MSIZE(size) (((size) & 0x7) << 11)
153 	/* Source Transfer Width */
154 #define	DMA_CTL_SRC_TRWID(size) (((size) & 0x7) << 4)
155 	/* Destination Transfer Width */
156 #define	DMA_CTL_DST_TRWID(size) (((size) & 0x7) << 1)
157 
158 /* Assign HW handshaking interface (x) to destination / source peripheral */
159 #define	DMA_CFG_HW_HS_DEST(int_num) (((int_num) & 0xF) << 11)
160 #define	DMA_CFG_HW_HS_SRC(int_num) (((int_num) & 0xF) << 7)
161 #define	DMA_CFG_HW_CH_PRIOR(int_num) (((int_num) & 0xF) << 5)
162 #define	DMA_LLP_LMS(addr, master) (((addr) & 0xfffffffc) | (master))
163 
164 /*
165  * This define is used to set block chaining disabled in the control low
166  * register.  It is already in little endian format so it can be &'d dirctly.
167  * It is essentially: cpu_to_le32(~(DMA_CTL_LLP_SRCEN | DMA_CTL_LLP_DSTEN))
168  */
169 enum {
170 	DMA_CTL_LLP_DISABLE_LE32 = 0xffffffe7,
171 	DMA_CTL_TTFC_P2M_DMAC =	0x00000002, /* Per to mem, DMAC cntr */
172 	DMA_CTL_TTFC_M2P_PER =	0x00000003, /* Mem to per, peripheral cntr */
173 	DMA_CTL_SINC_INC =	0x00000000, /* Source Address Increment */
174 	DMA_CTL_SINC_DEC =	0x00000200,
175 	DMA_CTL_SINC_NOCHANGE =	0x00000400,
176 	DMA_CTL_DINC_INC =	0x00000000, /* Destination Address Increment */
177 	DMA_CTL_DINC_DEC =	0x00000080,
178 	DMA_CTL_DINC_NOCHANGE =	0x00000100,
179 	DMA_CTL_INT_EN =	0x00000001, /* Interrupt Enable */
180 
181 /* Channel Configuration Register high bits */
182 	DMA_CFG_FCMOD_REQ =	0x00000001, /* Flow Control - request based */
183 	DMA_CFG_PROTCTL	=	(0x00000003 << 2),/* Protection Control */
184 
185 /* Channel Configuration Register low bits */
186 	DMA_CFG_RELD_DST =	0x80000000, /* Reload Dest / Src Addr */
187 	DMA_CFG_RELD_SRC =	0x40000000,
188 	DMA_CFG_HS_SELSRC =	0x00000800, /* Software handshake Src/ Dest */
189 	DMA_CFG_HS_SELDST =	0x00000400,
190 	DMA_CFG_FIFOEMPTY =     (0x00000001 << 9), /* FIFO Empty bit */
191 
192 /* Channel Linked List Pointer Register */
193 	DMA_LLP_AHBMASTER1 =	0,	/* List Master Select */
194 	DMA_LLP_AHBMASTER2 =	1,
195 
196 	SATA_DWC_MAX_PORTS = 1,
197 
198 	SATA_DWC_SCR_OFFSET = 0x24,
199 	SATA_DWC_REG_OFFSET = 0x64,
200 };
201 
202 /* DWC SATA Registers */
203 struct sata_dwc_regs {
204 	u32 fptagr;		/* 1st party DMA tag */
205 	u32 fpbor;		/* 1st party DMA buffer offset */
206 	u32 fptcr;		/* 1st party DMA Xfr count */
207 	u32 dmacr;		/* DMA Control */
208 	u32 dbtsr;		/* DMA Burst Transac size */
209 	u32 intpr;		/* Interrupt Pending */
210 	u32 intmr;		/* Interrupt Mask */
211 	u32 errmr;		/* Error Mask */
212 	u32 llcr;		/* Link Layer Control */
213 	u32 phycr;		/* PHY Control */
214 	u32 physr;		/* PHY Status */
215 	u32 rxbistpd;		/* Recvd BIST pattern def register */
216 	u32 rxbistpd1;		/* Recvd BIST data dword1 */
217 	u32 rxbistpd2;		/* Recvd BIST pattern data dword2 */
218 	u32 txbistpd;		/* Trans BIST pattern def register */
219 	u32 txbistpd1;		/* Trans BIST data dword1 */
220 	u32 txbistpd2;		/* Trans BIST data dword2 */
221 	u32 bistcr;		/* BIST Control Register */
222 	u32 bistfctr;		/* BIST FIS Count Register */
223 	u32 bistsr;		/* BIST Status Register */
224 	u32 bistdecr;		/* BIST Dword Error count register */
225 	u32 res[15];		/* Reserved locations */
226 	u32 testr;		/* Test Register */
227 	u32 versionr;		/* Version Register */
228 	u32 idr;		/* ID Register */
229 	u32 unimpl[192];	/* Unimplemented */
230 	u32 dmadr[256];	/* FIFO Locations in DMA Mode */
231 };
232 
233 enum {
234 	SCR_SCONTROL_DET_ENABLE	=	0x00000001,
235 	SCR_SSTATUS_DET_PRESENT	=	0x00000001,
236 	SCR_SERROR_DIAG_X	=	0x04000000,
237 /* DWC SATA Register Operations */
238 	SATA_DWC_TXFIFO_DEPTH	=	0x01FF,
239 	SATA_DWC_RXFIFO_DEPTH	=	0x01FF,
240 	SATA_DWC_DMACR_TMOD_TXCHEN =	0x00000004,
241 	SATA_DWC_DMACR_TXCHEN	= (0x00000001 | SATA_DWC_DMACR_TMOD_TXCHEN),
242 	SATA_DWC_DMACR_RXCHEN	= (0x00000002 | SATA_DWC_DMACR_TMOD_TXCHEN),
243 	SATA_DWC_DMACR_TXRXCH_CLEAR =	SATA_DWC_DMACR_TMOD_TXCHEN,
244 	SATA_DWC_INTPR_DMAT	=	0x00000001,
245 	SATA_DWC_INTPR_NEWFP	=	0x00000002,
246 	SATA_DWC_INTPR_PMABRT	=	0x00000004,
247 	SATA_DWC_INTPR_ERR	=	0x00000008,
248 	SATA_DWC_INTPR_NEWBIST	=	0x00000010,
249 	SATA_DWC_INTPR_IPF	=	0x10000000,
250 	SATA_DWC_INTMR_DMATM	=	0x00000001,
251 	SATA_DWC_INTMR_NEWFPM	=	0x00000002,
252 	SATA_DWC_INTMR_PMABRTM	=	0x00000004,
253 	SATA_DWC_INTMR_ERRM	=	0x00000008,
254 	SATA_DWC_INTMR_NEWBISTM	=	0x00000010,
255 	SATA_DWC_LLCR_SCRAMEN	=	0x00000001,
256 	SATA_DWC_LLCR_DESCRAMEN	=	0x00000002,
257 	SATA_DWC_LLCR_RPDEN	=	0x00000004,
258 /* This is all error bits, zero's are reserved fields. */
259 	SATA_DWC_SERROR_ERR_BITS =	0x0FFF0F03
260 };
261 
262 #define SATA_DWC_SCR0_SPD_GET(v)	(((v) >> 4) & 0x0000000F)
263 #define SATA_DWC_DMACR_TX_CLEAR(v)	(((v) & ~SATA_DWC_DMACR_TXCHEN) |\
264 						 SATA_DWC_DMACR_TMOD_TXCHEN)
265 #define SATA_DWC_DMACR_RX_CLEAR(v)	(((v) & ~SATA_DWC_DMACR_RXCHEN) |\
266 						 SATA_DWC_DMACR_TMOD_TXCHEN)
267 #define SATA_DWC_DBTSR_MWR(size)	(((size)/4) & SATA_DWC_TXFIFO_DEPTH)
268 #define SATA_DWC_DBTSR_MRD(size)	((((size)/4) & SATA_DWC_RXFIFO_DEPTH)\
269 						 << 16)
270 struct sata_dwc_device {
271 	struct device		*dev;		/* generic device struct */
272 	struct ata_probe_ent	*pe;		/* ptr to probe-ent */
273 	struct ata_host		*host;
274 	u8			*reg_base;
275 	struct sata_dwc_regs	*sata_dwc_regs;	/* DW Synopsys SATA specific */
276 	int			irq_dma;
277 };
278 
279 #define SATA_DWC_QCMD_MAX	32
280 
281 struct sata_dwc_device_port {
282 	struct sata_dwc_device	*hsdev;
283 	int			cmd_issued[SATA_DWC_QCMD_MAX];
284 	struct lli		*llit[SATA_DWC_QCMD_MAX];  /* DMA LLI table */
285 	dma_addr_t		llit_dma[SATA_DWC_QCMD_MAX];
286 	u32			dma_chan[SATA_DWC_QCMD_MAX];
287 	int			dma_pending[SATA_DWC_QCMD_MAX];
288 };
289 
290 /*
291  * Commonly used DWC SATA driver Macros
292  */
293 #define HSDEV_FROM_HOST(host)  ((struct sata_dwc_device *)\
294 					(host)->private_data)
295 #define HSDEV_FROM_AP(ap)  ((struct sata_dwc_device *)\
296 					(ap)->host->private_data)
297 #define HSDEVP_FROM_AP(ap)   ((struct sata_dwc_device_port *)\
298 					(ap)->private_data)
299 #define HSDEV_FROM_QC(qc)	((struct sata_dwc_device *)\
300 					(qc)->ap->host->private_data)
301 #define HSDEV_FROM_HSDEVP(p)	((struct sata_dwc_device *)\
302 						(hsdevp)->hsdev)
303 
304 enum {
305 	SATA_DWC_CMD_ISSUED_NOT		= 0,
306 	SATA_DWC_CMD_ISSUED_PEND	= 1,
307 	SATA_DWC_CMD_ISSUED_EXEC	= 2,
308 	SATA_DWC_CMD_ISSUED_NODATA	= 3,
309 
310 	SATA_DWC_DMA_PENDING_NONE	= 0,
311 	SATA_DWC_DMA_PENDING_TX		= 1,
312 	SATA_DWC_DMA_PENDING_RX		= 2,
313 };
314 
315 struct sata_dwc_host_priv {
316 	void	__iomem	 *scr_addr_sstatus;
317 	u32	sata_dwc_sactive_issued ;
318 	u32	sata_dwc_sactive_queued ;
319 	u32	dma_interrupt_count;
320 	struct	ahb_dma_regs	*sata_dma_regs;
321 	struct	device	*dwc_dev;
322 	int	dma_channel;
323 };
324 struct sata_dwc_host_priv host_pvt;
325 /*
326  * Prototypes
327  */
328 static void sata_dwc_bmdma_start_by_tag(struct ata_queued_cmd *qc, u8 tag);
329 static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc,
330 				u32 check_status);
331 static void sata_dwc_dma_xfer_complete(struct ata_port *ap, u32 check_status);
332 static void sata_dwc_port_stop(struct ata_port *ap);
333 static void sata_dwc_clear_dmacr(struct sata_dwc_device_port *hsdevp, u8 tag);
334 static int dma_dwc_init(struct sata_dwc_device *hsdev, int irq);
335 static void dma_dwc_exit(struct sata_dwc_device *hsdev);
336 static int dma_dwc_xfer_setup(struct scatterlist *sg, int num_elems,
337 			      struct lli *lli, dma_addr_t dma_lli,
338 			      void __iomem *addr, int dir);
339 static void dma_dwc_xfer_start(int dma_ch);
340 
341 static const char *get_prot_descript(u8 protocol)
342 {
343 	switch ((enum ata_tf_protocols)protocol) {
344 	case ATA_PROT_NODATA:
345 		return "ATA no data";
346 	case ATA_PROT_PIO:
347 		return "ATA PIO";
348 	case ATA_PROT_DMA:
349 		return "ATA DMA";
350 	case ATA_PROT_NCQ:
351 		return "ATA NCQ";
352 	case ATAPI_PROT_NODATA:
353 		return "ATAPI no data";
354 	case ATAPI_PROT_PIO:
355 		return "ATAPI PIO";
356 	case ATAPI_PROT_DMA:
357 		return "ATAPI DMA";
358 	default:
359 		return "unknown";
360 	}
361 }
362 
363 static const char *get_dma_dir_descript(int dma_dir)
364 {
365 	switch ((enum dma_data_direction)dma_dir) {
366 	case DMA_BIDIRECTIONAL:
367 		return "bidirectional";
368 	case DMA_TO_DEVICE:
369 		return "to device";
370 	case DMA_FROM_DEVICE:
371 		return "from device";
372 	default:
373 		return "none";
374 	}
375 }
376 
377 static void sata_dwc_tf_dump(struct ata_taskfile *tf)
378 {
379 	dev_vdbg(host_pvt.dwc_dev, "taskfile cmd: 0x%02x protocol: %s flags:"
380 		"0x%lx device: %x\n", tf->command,
381 		get_prot_descript(tf->protocol), tf->flags, tf->device);
382 	dev_vdbg(host_pvt.dwc_dev, "feature: 0x%02x nsect: 0x%x lbal: 0x%x "
383 		"lbam: 0x%x lbah: 0x%x\n", tf->feature, tf->nsect, tf->lbal,
384 		 tf->lbam, tf->lbah);
385 	dev_vdbg(host_pvt.dwc_dev, "hob_feature: 0x%02x hob_nsect: 0x%x "
386 		"hob_lbal: 0x%x hob_lbam: 0x%x hob_lbah: 0x%x\n",
387 		tf->hob_feature, tf->hob_nsect, tf->hob_lbal, tf->hob_lbam,
388 		tf->hob_lbah);
389 }
390 
391 /*
392  * Function: get_burst_length_encode
393  * arguments: datalength: length in bytes of data
394  * returns value to be programmed in register corresponding to data length
395  * This value is effectively the log(base 2) of the length
396  */
397 static  int get_burst_length_encode(int datalength)
398 {
399 	int items = datalength >> 2;	/* div by 4 to get lword count */
400 
401 	if (items >= 64)
402 		return 5;
403 
404 	if (items >= 32)
405 		return 4;
406 
407 	if (items >= 16)
408 		return 3;
409 
410 	if (items >= 8)
411 		return 2;
412 
413 	if (items >= 4)
414 		return 1;
415 
416 	return 0;
417 }
418 
419 static  void clear_chan_interrupts(int c)
420 {
421 	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.tfr.low),
422 		 DMA_CHANNEL(c));
423 	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.block.low),
424 		 DMA_CHANNEL(c));
425 	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.srctran.low),
426 		 DMA_CHANNEL(c));
427 	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.dsttran.low),
428 		 DMA_CHANNEL(c));
429 	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.error.low),
430 		 DMA_CHANNEL(c));
431 }
432 
433 /*
434  * Function: dma_request_channel
435  * arguments: None
436  * returns channel number if available else -1
437  * This function assigns the next available DMA channel from the list to the
438  * requester
439  */
440 static int dma_request_channel(void)
441 {
442 	/* Check if the channel is not currently in use */
443 	if (!(in_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low)) &
444 		DMA_CHANNEL(host_pvt.dma_channel)))
445 		return host_pvt.dma_channel;
446 	dev_err(host_pvt.dwc_dev, "%s Channel %d is currently in use\n",
447 		__func__, host_pvt.dma_channel);
448 	return -1;
449 }
450 
451 /*
452  * Function: dma_dwc_interrupt
453  * arguments: irq, dev_id, pt_regs
454  * returns channel number if available else -1
455  * Interrupt Handler for DW AHB SATA DMA
456  */
457 static irqreturn_t dma_dwc_interrupt(int irq, void *hsdev_instance)
458 {
459 	int chan;
460 	u32 tfr_reg, err_reg;
461 	unsigned long flags;
462 	struct sata_dwc_device *hsdev =
463 		(struct sata_dwc_device *)hsdev_instance;
464 	struct ata_host *host = (struct ata_host *)hsdev->host;
465 	struct ata_port *ap;
466 	struct sata_dwc_device_port *hsdevp;
467 	u8 tag = 0;
468 	unsigned int port = 0;
469 
470 	spin_lock_irqsave(&host->lock, flags);
471 	ap = host->ports[port];
472 	hsdevp = HSDEVP_FROM_AP(ap);
473 	tag = ap->link.active_tag;
474 
475 	tfr_reg = in_le32(&(host_pvt.sata_dma_regs->interrupt_status.tfr\
476 			.low));
477 	err_reg = in_le32(&(host_pvt.sata_dma_regs->interrupt_status.error\
478 			.low));
479 
480 	dev_dbg(ap->dev, "eot=0x%08x err=0x%08x pending=%d active port=%d\n",
481 		tfr_reg, err_reg, hsdevp->dma_pending[tag], port);
482 
483 	chan = host_pvt.dma_channel;
484 	if (chan >= 0) {
485 		/* Check for end-of-transfer interrupt. */
486 		if (tfr_reg & DMA_CHANNEL(chan)) {
487 			/*
488 			 * Each DMA command produces 2 interrupts.  Only
489 			 * complete the command after both interrupts have been
490 			 * seen. (See sata_dwc_isr())
491 			 */
492 			host_pvt.dma_interrupt_count++;
493 			sata_dwc_clear_dmacr(hsdevp, tag);
494 
495 			if (hsdevp->dma_pending[tag] ==
496 			    SATA_DWC_DMA_PENDING_NONE) {
497 				dev_err(ap->dev, "DMA not pending eot=0x%08x "
498 					"err=0x%08x tag=0x%02x pending=%d\n",
499 					tfr_reg, err_reg, tag,
500 					hsdevp->dma_pending[tag]);
501 			}
502 
503 			if ((host_pvt.dma_interrupt_count % 2) == 0)
504 				sata_dwc_dma_xfer_complete(ap, 1);
505 
506 			/* Clear the interrupt */
507 			out_le32(&(host_pvt.sata_dma_regs->interrupt_clear\
508 				.tfr.low),
509 				 DMA_CHANNEL(chan));
510 		}
511 
512 		/* Check for error interrupt. */
513 		if (err_reg & DMA_CHANNEL(chan)) {
514 			/* TODO Need error handler ! */
515 			dev_err(ap->dev, "error interrupt err_reg=0x%08x\n",
516 				err_reg);
517 
518 			/* Clear the interrupt. */
519 			out_le32(&(host_pvt.sata_dma_regs->interrupt_clear\
520 				.error.low),
521 				 DMA_CHANNEL(chan));
522 		}
523 	}
524 	spin_unlock_irqrestore(&host->lock, flags);
525 	return IRQ_HANDLED;
526 }
527 
528 /*
529  * Function: dma_request_interrupts
530  * arguments: hsdev
531  * returns status
532  * This function registers ISR for a particular DMA channel interrupt
533  */
534 static int dma_request_interrupts(struct sata_dwc_device *hsdev, int irq)
535 {
536 	int retval = 0;
537 	int chan = host_pvt.dma_channel;
538 
539 	if (chan >= 0) {
540 		/* Unmask error interrupt */
541 		out_le32(&(host_pvt.sata_dma_regs)->interrupt_mask.error.low,
542 			 DMA_ENABLE_CHAN(chan));
543 
544 		/* Unmask end-of-transfer interrupt */
545 		out_le32(&(host_pvt.sata_dma_regs)->interrupt_mask.tfr.low,
546 			 DMA_ENABLE_CHAN(chan));
547 	}
548 
549 	retval = request_irq(irq, dma_dwc_interrupt, 0, "SATA DMA", hsdev);
550 	if (retval) {
551 		dev_err(host_pvt.dwc_dev, "%s: could not get IRQ %d\n",
552 		__func__, irq);
553 		return -ENODEV;
554 	}
555 
556 	/* Mark this interrupt as requested */
557 	hsdev->irq_dma = irq;
558 	return 0;
559 }
560 
561 /*
562  * Function: map_sg_to_lli
563  * The Synopsis driver has a comment proposing that better performance
564  * is possible by only enabling interrupts on the last item in the linked list.
565  * However, it seems that could be a problem if an error happened on one of the
566  * first items.  The transfer would halt, but no error interrupt would occur.
567  * Currently this function sets interrupts enabled for each linked list item:
568  * DMA_CTL_INT_EN.
569  */
570 static int map_sg_to_lli(struct scatterlist *sg, int num_elems,
571 			struct lli *lli, dma_addr_t dma_lli,
572 			void __iomem *dmadr_addr, int dir)
573 {
574 	int i, idx = 0;
575 	int fis_len = 0;
576 	dma_addr_t next_llp;
577 	int bl;
578 	int sms_val, dms_val;
579 
580 	sms_val = 0;
581 	dms_val = 1 + host_pvt.dma_channel;
582 	dev_dbg(host_pvt.dwc_dev, "%s: sg=%p nelem=%d lli=%p dma_lli=0x%08x"
583 		" dmadr=0x%08x\n", __func__, sg, num_elems, lli, (u32)dma_lli,
584 		(u32)dmadr_addr);
585 
586 	bl = get_burst_length_encode(AHB_DMA_BRST_DFLT);
587 
588 	for (i = 0; i < num_elems; i++, sg++) {
589 		u32 addr, offset;
590 		u32 sg_len, len;
591 
592 		addr = (u32) sg_dma_address(sg);
593 		sg_len = sg_dma_len(sg);
594 
595 		dev_dbg(host_pvt.dwc_dev, "%s: elem=%d sg_addr=0x%x sg_len"
596 			"=%d\n", __func__, i, addr, sg_len);
597 
598 		while (sg_len) {
599 			if (idx >= SATA_DWC_DMAC_LLI_NUM) {
600 				/* The LLI table is not large enough. */
601 				dev_err(host_pvt.dwc_dev, "LLI table overrun "
602 				"(idx=%d)\n", idx);
603 				break;
604 			}
605 			len = (sg_len > SATA_DWC_DMAC_CTRL_TSIZE_MAX) ?
606 				SATA_DWC_DMAC_CTRL_TSIZE_MAX : sg_len;
607 
608 			offset = addr & 0xffff;
609 			if ((offset + sg_len) > 0x10000)
610 				len = 0x10000 - offset;
611 
612 			/*
613 			 * Make sure a LLI block is not created that will span
614 			 * 8K max FIS boundary.  If the block spans such a FIS
615 			 * boundary, there is a chance that a DMA burst will
616 			 * cross that boundary -- this results in an error in
617 			 * the host controller.
618 			 */
619 			if (fis_len + len > 8192) {
620 				dev_dbg(host_pvt.dwc_dev, "SPLITTING: fis_len="
621 					"%d(0x%x) len=%d(0x%x)\n", fis_len,
622 					 fis_len, len, len);
623 				len = 8192 - fis_len;
624 				fis_len = 0;
625 			} else {
626 				fis_len += len;
627 			}
628 			if (fis_len == 8192)
629 				fis_len = 0;
630 
631 			/*
632 			 * Set DMA addresses and lower half of control register
633 			 * based on direction.
634 			 */
635 			if (dir == DMA_FROM_DEVICE) {
636 				lli[idx].dar = cpu_to_le32(addr);
637 				lli[idx].sar = cpu_to_le32((u32)dmadr_addr);
638 
639 				lli[idx].ctl.low = cpu_to_le32(
640 					DMA_CTL_TTFC(DMA_CTL_TTFC_P2M_DMAC) |
641 					DMA_CTL_SMS(sms_val) |
642 					DMA_CTL_DMS(dms_val) |
643 					DMA_CTL_SRC_MSIZE(bl) |
644 					DMA_CTL_DST_MSIZE(bl) |
645 					DMA_CTL_SINC_NOCHANGE |
646 					DMA_CTL_SRC_TRWID(2) |
647 					DMA_CTL_DST_TRWID(2) |
648 					DMA_CTL_INT_EN |
649 					DMA_CTL_LLP_SRCEN |
650 					DMA_CTL_LLP_DSTEN);
651 			} else {	/* DMA_TO_DEVICE */
652 				lli[idx].sar = cpu_to_le32(addr);
653 				lli[idx].dar = cpu_to_le32((u32)dmadr_addr);
654 
655 				lli[idx].ctl.low = cpu_to_le32(
656 					DMA_CTL_TTFC(DMA_CTL_TTFC_M2P_PER) |
657 					DMA_CTL_SMS(dms_val) |
658 					DMA_CTL_DMS(sms_val) |
659 					DMA_CTL_SRC_MSIZE(bl) |
660 					DMA_CTL_DST_MSIZE(bl) |
661 					DMA_CTL_DINC_NOCHANGE |
662 					DMA_CTL_SRC_TRWID(2) |
663 					DMA_CTL_DST_TRWID(2) |
664 					DMA_CTL_INT_EN |
665 					DMA_CTL_LLP_SRCEN |
666 					DMA_CTL_LLP_DSTEN);
667 			}
668 
669 			dev_dbg(host_pvt.dwc_dev, "%s setting ctl.high len: "
670 				"0x%08x val: 0x%08x\n", __func__,
671 				len, DMA_CTL_BLK_TS(len / 4));
672 
673 			/* Program the LLI CTL high register */
674 			lli[idx].ctl.high = cpu_to_le32(DMA_CTL_BLK_TS\
675 						(len / 4));
676 
677 			/* Program the next pointer.  The next pointer must be
678 			 * the physical address, not the virtual address.
679 			 */
680 			next_llp = (dma_lli + ((idx + 1) * sizeof(struct \
681 							lli)));
682 
683 			/* The last 2 bits encode the list master select. */
684 			next_llp = DMA_LLP_LMS(next_llp, DMA_LLP_AHBMASTER2);
685 
686 			lli[idx].llp = cpu_to_le32(next_llp);
687 			idx++;
688 			sg_len -= len;
689 			addr += len;
690 		}
691 	}
692 
693 	/*
694 	 * The last next ptr has to be zero and the last control low register
695 	 * has to have LLP_SRC_EN and LLP_DST_EN (linked list pointer source
696 	 * and destination enable) set back to 0 (disabled.) This is what tells
697 	 * the core that this is the last item in the linked list.
698 	 */
699 	if (idx) {
700 		lli[idx-1].llp = 0x00000000;
701 		lli[idx-1].ctl.low &= DMA_CTL_LLP_DISABLE_LE32;
702 
703 		/* Flush cache to memory */
704 		dma_cache_sync(NULL, lli, (sizeof(struct lli) * idx),
705 			       DMA_BIDIRECTIONAL);
706 	}
707 
708 	return idx;
709 }
710 
711 /*
712  * Function: dma_dwc_xfer_start
713  * arguments: Channel number
714  * Return : None
715  * Enables the DMA channel
716  */
717 static void dma_dwc_xfer_start(int dma_ch)
718 {
719 	/* Enable the DMA channel */
720 	out_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low),
721 		 in_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low)) |
722 		 DMA_ENABLE_CHAN(dma_ch));
723 }
724 
725 static int dma_dwc_xfer_setup(struct scatterlist *sg, int num_elems,
726 			      struct lli *lli, dma_addr_t dma_lli,
727 			      void __iomem *addr, int dir)
728 {
729 	int dma_ch;
730 	int num_lli;
731 	/* Acquire DMA channel */
732 	dma_ch = dma_request_channel();
733 	if (dma_ch == -1) {
734 		dev_err(host_pvt.dwc_dev, "%s: dma channel unavailable\n",
735 			 __func__);
736 		return -EAGAIN;
737 	}
738 
739 	/* Convert SG list to linked list of items (LLIs) for AHB DMA */
740 	num_lli = map_sg_to_lli(sg, num_elems, lli, dma_lli, addr, dir);
741 
742 	dev_dbg(host_pvt.dwc_dev, "%s sg: 0x%p, count: %d lli: %p dma_lli:"
743 		" 0x%0xlx addr: %p lli count: %d\n", __func__, sg, num_elems,
744 		 lli, (u32)dma_lli, addr, num_lli);
745 
746 	clear_chan_interrupts(dma_ch);
747 
748 	/* Program the CFG register. */
749 	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].cfg.high),
750 		 DMA_CFG_HW_HS_SRC(dma_ch) | DMA_CFG_HW_HS_DEST(dma_ch) |
751 		 DMA_CFG_PROTCTL | DMA_CFG_FCMOD_REQ);
752 	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].cfg.low),
753 		 DMA_CFG_HW_CH_PRIOR(dma_ch));
754 
755 	/* Program the address of the linked list */
756 	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].llp.low),
757 		 DMA_LLP_LMS(dma_lli, DMA_LLP_AHBMASTER2));
758 
759 	/* Program the CTL register with src enable / dst enable */
760 	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].ctl.low),
761 		 DMA_CTL_LLP_SRCEN | DMA_CTL_LLP_DSTEN);
762 	return dma_ch;
763 }
764 
765 /*
766  * Function: dma_dwc_exit
767  * arguments: None
768  * returns status
769  * This function exits the SATA DMA driver
770  */
771 static void dma_dwc_exit(struct sata_dwc_device *hsdev)
772 {
773 	dev_dbg(host_pvt.dwc_dev, "%s:\n", __func__);
774 	if (host_pvt.sata_dma_regs) {
775 		iounmap(host_pvt.sata_dma_regs);
776 		host_pvt.sata_dma_regs = NULL;
777 	}
778 
779 	if (hsdev->irq_dma) {
780 		free_irq(hsdev->irq_dma, hsdev);
781 		hsdev->irq_dma = 0;
782 	}
783 }
784 
785 /*
786  * Function: dma_dwc_init
787  * arguments: hsdev
788  * returns status
789  * This function initializes the SATA DMA driver
790  */
791 static int dma_dwc_init(struct sata_dwc_device *hsdev, int irq)
792 {
793 	int err;
794 
795 	err = dma_request_interrupts(hsdev, irq);
796 	if (err) {
797 		dev_err(host_pvt.dwc_dev, "%s: dma_request_interrupts returns"
798 			" %d\n", __func__, err);
799 		goto error_out;
800 	}
801 
802 	/* Enabe DMA */
803 	out_le32(&(host_pvt.sata_dma_regs->dma_cfg.low), DMA_EN);
804 
805 	dev_notice(host_pvt.dwc_dev, "DMA initialized\n");
806 	dev_dbg(host_pvt.dwc_dev, "SATA DMA registers=0x%p\n", host_pvt.\
807 		sata_dma_regs);
808 
809 	return 0;
810 
811 error_out:
812 	dma_dwc_exit(hsdev);
813 
814 	return err;
815 }
816 
817 static int sata_dwc_scr_read(struct ata_link *link, unsigned int scr, u32 *val)
818 {
819 	if (scr > SCR_NOTIFICATION) {
820 		dev_err(link->ap->dev, "%s: Incorrect SCR offset 0x%02x\n",
821 			__func__, scr);
822 		return -EINVAL;
823 	}
824 
825 	*val = in_le32((void *)link->ap->ioaddr.scr_addr + (scr * 4));
826 	dev_dbg(link->ap->dev, "%s: id=%d reg=%d val=val=0x%08x\n",
827 		__func__, link->ap->print_id, scr, *val);
828 
829 	return 0;
830 }
831 
832 static int sata_dwc_scr_write(struct ata_link *link, unsigned int scr, u32 val)
833 {
834 	dev_dbg(link->ap->dev, "%s: id=%d reg=%d val=val=0x%08x\n",
835 		__func__, link->ap->print_id, scr, val);
836 	if (scr > SCR_NOTIFICATION) {
837 		dev_err(link->ap->dev, "%s: Incorrect SCR offset 0x%02x\n",
838 			 __func__, scr);
839 		return -EINVAL;
840 	}
841 	out_le32((void *)link->ap->ioaddr.scr_addr + (scr * 4), val);
842 
843 	return 0;
844 }
845 
846 static u32 core_scr_read(unsigned int scr)
847 {
848 	return in_le32((void __iomem *)(host_pvt.scr_addr_sstatus) +\
849 			(scr * 4));
850 }
851 
852 static void core_scr_write(unsigned int scr, u32 val)
853 {
854 	out_le32((void __iomem *)(host_pvt.scr_addr_sstatus) + (scr * 4),
855 		val);
856 }
857 
858 static void clear_serror(void)
859 {
860 	u32 val;
861 	val = core_scr_read(SCR_ERROR);
862 	core_scr_write(SCR_ERROR, val);
863 
864 }
865 
866 static void clear_interrupt_bit(struct sata_dwc_device *hsdev, u32 bit)
867 {
868 	out_le32(&hsdev->sata_dwc_regs->intpr,
869 		 in_le32(&hsdev->sata_dwc_regs->intpr));
870 }
871 
872 static u32 qcmd_tag_to_mask(u8 tag)
873 {
874 	return 0x00000001 << (tag & 0x1f);
875 }
876 
877 /* See ahci.c */
878 static void sata_dwc_error_intr(struct ata_port *ap,
879 				struct sata_dwc_device *hsdev, uint intpr)
880 {
881 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
882 	struct ata_eh_info *ehi = &ap->link.eh_info;
883 	unsigned int err_mask = 0, action = 0;
884 	struct ata_queued_cmd *qc;
885 	u32 serror;
886 	u8 status, tag;
887 	u32 err_reg;
888 
889 	ata_ehi_clear_desc(ehi);
890 
891 	serror = core_scr_read(SCR_ERROR);
892 	status = ap->ops->sff_check_status(ap);
893 
894 	err_reg = in_le32(&(host_pvt.sata_dma_regs->interrupt_status.error.\
895 			low));
896 	tag = ap->link.active_tag;
897 
898 	dev_err(ap->dev, "%s SCR_ERROR=0x%08x intpr=0x%08x status=0x%08x "
899 		"dma_intp=%d pending=%d issued=%d dma_err_status=0x%08x\n",
900 		__func__, serror, intpr, status, host_pvt.dma_interrupt_count,
901 		hsdevp->dma_pending[tag], hsdevp->cmd_issued[tag], err_reg);
902 
903 	/* Clear error register and interrupt bit */
904 	clear_serror();
905 	clear_interrupt_bit(hsdev, SATA_DWC_INTPR_ERR);
906 
907 	/* This is the only error happening now.  TODO check for exact error */
908 
909 	err_mask |= AC_ERR_HOST_BUS;
910 	action |= ATA_EH_RESET;
911 
912 	/* Pass this on to EH */
913 	ehi->serror |= serror;
914 	ehi->action |= action;
915 
916 	qc = ata_qc_from_tag(ap, tag);
917 	if (qc)
918 		qc->err_mask |= err_mask;
919 	else
920 		ehi->err_mask |= err_mask;
921 
922 	ata_port_abort(ap);
923 }
924 
925 /*
926  * Function : sata_dwc_isr
927  * arguments : irq, void *dev_instance, struct pt_regs *regs
928  * Return value : irqreturn_t - status of IRQ
929  * This Interrupt handler called via port ops registered function.
930  * .irq_handler = sata_dwc_isr
931  */
932 static irqreturn_t sata_dwc_isr(int irq, void *dev_instance)
933 {
934 	struct ata_host *host = (struct ata_host *)dev_instance;
935 	struct sata_dwc_device *hsdev = HSDEV_FROM_HOST(host);
936 	struct ata_port *ap;
937 	struct ata_queued_cmd *qc;
938 	unsigned long flags;
939 	u8 status, tag;
940 	int handled, num_processed, port = 0;
941 	uint intpr, sactive, sactive2, tag_mask;
942 	struct sata_dwc_device_port *hsdevp;
943 	host_pvt.sata_dwc_sactive_issued = 0;
944 
945 	spin_lock_irqsave(&host->lock, flags);
946 
947 	/* Read the interrupt register */
948 	intpr = in_le32(&hsdev->sata_dwc_regs->intpr);
949 
950 	ap = host->ports[port];
951 	hsdevp = HSDEVP_FROM_AP(ap);
952 
953 	dev_dbg(ap->dev, "%s intpr=0x%08x active_tag=%d\n", __func__, intpr,
954 		ap->link.active_tag);
955 
956 	/* Check for error interrupt */
957 	if (intpr & SATA_DWC_INTPR_ERR) {
958 		sata_dwc_error_intr(ap, hsdev, intpr);
959 		handled = 1;
960 		goto DONE;
961 	}
962 
963 	/* Check for DMA SETUP FIS (FP DMA) interrupt */
964 	if (intpr & SATA_DWC_INTPR_NEWFP) {
965 		clear_interrupt_bit(hsdev, SATA_DWC_INTPR_NEWFP);
966 
967 		tag = (u8)(in_le32(&hsdev->sata_dwc_regs->fptagr));
968 		dev_dbg(ap->dev, "%s: NEWFP tag=%d\n", __func__, tag);
969 		if (hsdevp->cmd_issued[tag] != SATA_DWC_CMD_ISSUED_PEND)
970 			dev_warn(ap->dev, "CMD tag=%d not pending?\n", tag);
971 
972 		host_pvt.sata_dwc_sactive_issued |= qcmd_tag_to_mask(tag);
973 
974 		qc = ata_qc_from_tag(ap, tag);
975 		/*
976 		 * Start FP DMA for NCQ command.  At this point the tag is the
977 		 * active tag.  It is the tag that matches the command about to
978 		 * be completed.
979 		 */
980 		qc->ap->link.active_tag = tag;
981 		sata_dwc_bmdma_start_by_tag(qc, tag);
982 
983 		handled = 1;
984 		goto DONE;
985 	}
986 	sactive = core_scr_read(SCR_ACTIVE);
987 	tag_mask = (host_pvt.sata_dwc_sactive_issued | sactive) ^ sactive;
988 
989 	/* If no sactive issued and tag_mask is zero then this is not NCQ */
990 	if (host_pvt.sata_dwc_sactive_issued == 0 && tag_mask == 0) {
991 		if (ap->link.active_tag == ATA_TAG_POISON)
992 			tag = 0;
993 		else
994 			tag = ap->link.active_tag;
995 		qc = ata_qc_from_tag(ap, tag);
996 
997 		/* DEV interrupt w/ no active qc? */
998 		if (unlikely(!qc || (qc->tf.flags & ATA_TFLAG_POLLING))) {
999 			dev_err(ap->dev, "%s interrupt with no active qc "
1000 				"qc=%p\n", __func__, qc);
1001 			ap->ops->sff_check_status(ap);
1002 			handled = 1;
1003 			goto DONE;
1004 		}
1005 		status = ap->ops->sff_check_status(ap);
1006 
1007 		qc->ap->link.active_tag = tag;
1008 		hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT;
1009 
1010 		if (status & ATA_ERR) {
1011 			dev_dbg(ap->dev, "interrupt ATA_ERR (0x%x)\n", status);
1012 			sata_dwc_qc_complete(ap, qc, 1);
1013 			handled = 1;
1014 			goto DONE;
1015 		}
1016 
1017 		dev_dbg(ap->dev, "%s non-NCQ cmd interrupt, protocol: %s\n",
1018 			__func__, get_prot_descript(qc->tf.protocol));
1019 DRVSTILLBUSY:
1020 		if (ata_is_dma(qc->tf.protocol)) {
1021 			/*
1022 			 * Each DMA transaction produces 2 interrupts. The DMAC
1023 			 * transfer complete interrupt and the SATA controller
1024 			 * operation done interrupt. The command should be
1025 			 * completed only after both interrupts are seen.
1026 			 */
1027 			host_pvt.dma_interrupt_count++;
1028 			if (hsdevp->dma_pending[tag] == \
1029 					SATA_DWC_DMA_PENDING_NONE) {
1030 				dev_err(ap->dev, "%s: DMA not pending "
1031 					"intpr=0x%08x status=0x%08x pending"
1032 					"=%d\n", __func__, intpr, status,
1033 					hsdevp->dma_pending[tag]);
1034 			}
1035 
1036 			if ((host_pvt.dma_interrupt_count % 2) == 0)
1037 				sata_dwc_dma_xfer_complete(ap, 1);
1038 		} else if (ata_is_pio(qc->tf.protocol)) {
1039 			ata_sff_hsm_move(ap, qc, status, 0);
1040 			handled = 1;
1041 			goto DONE;
1042 		} else {
1043 			if (unlikely(sata_dwc_qc_complete(ap, qc, 1)))
1044 				goto DRVSTILLBUSY;
1045 		}
1046 
1047 		handled = 1;
1048 		goto DONE;
1049 	}
1050 
1051 	/*
1052 	 * This is a NCQ command. At this point we need to figure out for which
1053 	 * tags we have gotten a completion interrupt.  One interrupt may serve
1054 	 * as completion for more than one operation when commands are queued
1055 	 * (NCQ).  We need to process each completed command.
1056 	 */
1057 
1058 	 /* process completed commands */
1059 	sactive = core_scr_read(SCR_ACTIVE);
1060 	tag_mask = (host_pvt.sata_dwc_sactive_issued | sactive) ^ sactive;
1061 
1062 	if (sactive != 0 || (host_pvt.sata_dwc_sactive_issued) > 1 || \
1063 							tag_mask > 1) {
1064 		dev_dbg(ap->dev, "%s NCQ:sactive=0x%08x  sactive_issued=0x%08x"
1065 			"tag_mask=0x%08x\n", __func__, sactive,
1066 			host_pvt.sata_dwc_sactive_issued, tag_mask);
1067 	}
1068 
1069 	if ((tag_mask | (host_pvt.sata_dwc_sactive_issued)) != \
1070 					(host_pvt.sata_dwc_sactive_issued)) {
1071 		dev_warn(ap->dev, "Bad tag mask?  sactive=0x%08x "
1072 			 "(host_pvt.sata_dwc_sactive_issued)=0x%08x  tag_mask"
1073 			 "=0x%08x\n", sactive, host_pvt.sata_dwc_sactive_issued,
1074 			  tag_mask);
1075 	}
1076 
1077 	/* read just to clear ... not bad if currently still busy */
1078 	status = ap->ops->sff_check_status(ap);
1079 	dev_dbg(ap->dev, "%s ATA status register=0x%x\n", __func__, status);
1080 
1081 	tag = 0;
1082 	num_processed = 0;
1083 	while (tag_mask) {
1084 		num_processed++;
1085 		while (!(tag_mask & 0x00000001)) {
1086 			tag++;
1087 			tag_mask <<= 1;
1088 		}
1089 
1090 		tag_mask &= (~0x00000001);
1091 		qc = ata_qc_from_tag(ap, tag);
1092 
1093 		/* To be picked up by completion functions */
1094 		qc->ap->link.active_tag = tag;
1095 		hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT;
1096 
1097 		/* Let libata/scsi layers handle error */
1098 		if (status & ATA_ERR) {
1099 			dev_dbg(ap->dev, "%s ATA_ERR (0x%x)\n", __func__,
1100 				status);
1101 			sata_dwc_qc_complete(ap, qc, 1);
1102 			handled = 1;
1103 			goto DONE;
1104 		}
1105 
1106 		/* Process completed command */
1107 		dev_dbg(ap->dev, "%s NCQ command, protocol: %s\n", __func__,
1108 			get_prot_descript(qc->tf.protocol));
1109 		if (ata_is_dma(qc->tf.protocol)) {
1110 			host_pvt.dma_interrupt_count++;
1111 			if (hsdevp->dma_pending[tag] == \
1112 					SATA_DWC_DMA_PENDING_NONE)
1113 				dev_warn(ap->dev, "%s: DMA not pending?\n",
1114 					__func__);
1115 			if ((host_pvt.dma_interrupt_count % 2) == 0)
1116 				sata_dwc_dma_xfer_complete(ap, 1);
1117 		} else {
1118 			if (unlikely(sata_dwc_qc_complete(ap, qc, 1)))
1119 				goto STILLBUSY;
1120 		}
1121 		continue;
1122 
1123 STILLBUSY:
1124 		ap->stats.idle_irq++;
1125 		dev_warn(ap->dev, "STILL BUSY IRQ ata%d: irq trap\n",
1126 			ap->print_id);
1127 	} /* while tag_mask */
1128 
1129 	/*
1130 	 * Check to see if any commands completed while we were processing our
1131 	 * initial set of completed commands (read status clears interrupts,
1132 	 * so we might miss a completed command interrupt if one came in while
1133 	 * we were processing --we read status as part of processing a completed
1134 	 * command).
1135 	 */
1136 	sactive2 = core_scr_read(SCR_ACTIVE);
1137 	if (sactive2 != sactive) {
1138 		dev_dbg(ap->dev, "More completed - sactive=0x%x sactive2"
1139 			"=0x%x\n", sactive, sactive2);
1140 	}
1141 	handled = 1;
1142 
1143 DONE:
1144 	spin_unlock_irqrestore(&host->lock, flags);
1145 	return IRQ_RETVAL(handled);
1146 }
1147 
1148 static void sata_dwc_clear_dmacr(struct sata_dwc_device_port *hsdevp, u8 tag)
1149 {
1150 	struct sata_dwc_device *hsdev = HSDEV_FROM_HSDEVP(hsdevp);
1151 
1152 	if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_RX) {
1153 		out_le32(&(hsdev->sata_dwc_regs->dmacr),
1154 			 SATA_DWC_DMACR_RX_CLEAR(
1155 				 in_le32(&(hsdev->sata_dwc_regs->dmacr))));
1156 	} else if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_TX) {
1157 		out_le32(&(hsdev->sata_dwc_regs->dmacr),
1158 			 SATA_DWC_DMACR_TX_CLEAR(
1159 				 in_le32(&(hsdev->sata_dwc_regs->dmacr))));
1160 	} else {
1161 		/*
1162 		 * This should not happen, it indicates the driver is out of
1163 		 * sync.  If it does happen, clear dmacr anyway.
1164 		 */
1165 		dev_err(host_pvt.dwc_dev, "%s DMA protocol RX and"
1166 			"TX DMA not pending tag=0x%02x pending=%d"
1167 			" dmacr: 0x%08x\n", __func__, tag,
1168 			hsdevp->dma_pending[tag],
1169 			in_le32(&(hsdev->sata_dwc_regs->dmacr)));
1170 		out_le32(&(hsdev->sata_dwc_regs->dmacr),
1171 			SATA_DWC_DMACR_TXRXCH_CLEAR);
1172 	}
1173 }
1174 
1175 static void sata_dwc_dma_xfer_complete(struct ata_port *ap, u32 check_status)
1176 {
1177 	struct ata_queued_cmd *qc;
1178 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1179 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
1180 	u8 tag = 0;
1181 
1182 	tag = ap->link.active_tag;
1183 	qc = ata_qc_from_tag(ap, tag);
1184 	if (!qc) {
1185 		dev_err(ap->dev, "failed to get qc");
1186 		return;
1187 	}
1188 
1189 #ifdef DEBUG_NCQ
1190 	if (tag > 0) {
1191 		dev_info(ap->dev, "%s tag=%u cmd=0x%02x dma dir=%s proto=%s "
1192 			 "dmacr=0x%08x\n", __func__, qc->tag, qc->tf.command,
1193 			 get_dma_dir_descript(qc->dma_dir),
1194 			 get_prot_descript(qc->tf.protocol),
1195 			 in_le32(&(hsdev->sata_dwc_regs->dmacr)));
1196 	}
1197 #endif
1198 
1199 	if (ata_is_dma(qc->tf.protocol)) {
1200 		if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_NONE) {
1201 			dev_err(ap->dev, "%s DMA protocol RX and TX DMA not "
1202 				"pending dmacr: 0x%08x\n", __func__,
1203 				in_le32(&(hsdev->sata_dwc_regs->dmacr)));
1204 		}
1205 
1206 		hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_NONE;
1207 		sata_dwc_qc_complete(ap, qc, check_status);
1208 		ap->link.active_tag = ATA_TAG_POISON;
1209 	} else {
1210 		sata_dwc_qc_complete(ap, qc, check_status);
1211 	}
1212 }
1213 
1214 static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc,
1215 				u32 check_status)
1216 {
1217 	u8 status = 0;
1218 	u32 mask = 0x0;
1219 	u8 tag = qc->tag;
1220 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1221 	host_pvt.sata_dwc_sactive_queued = 0;
1222 	dev_dbg(ap->dev, "%s checkstatus? %x\n", __func__, check_status);
1223 
1224 	if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_TX)
1225 		dev_err(ap->dev, "TX DMA PENDING\n");
1226 	else if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_RX)
1227 		dev_err(ap->dev, "RX DMA PENDING\n");
1228 	dev_dbg(ap->dev, "QC complete cmd=0x%02x status=0x%02x ata%u:"
1229 		" protocol=%d\n", qc->tf.command, status, ap->print_id,
1230 		 qc->tf.protocol);
1231 
1232 	/* clear active bit */
1233 	mask = (~(qcmd_tag_to_mask(tag)));
1234 	host_pvt.sata_dwc_sactive_queued = (host_pvt.sata_dwc_sactive_queued) \
1235 						& mask;
1236 	host_pvt.sata_dwc_sactive_issued = (host_pvt.sata_dwc_sactive_issued) \
1237 						& mask;
1238 	ata_qc_complete(qc);
1239 	return 0;
1240 }
1241 
1242 static void sata_dwc_enable_interrupts(struct sata_dwc_device *hsdev)
1243 {
1244 	/* Enable selective interrupts by setting the interrupt maskregister*/
1245 	out_le32(&hsdev->sata_dwc_regs->intmr,
1246 		 SATA_DWC_INTMR_ERRM |
1247 		 SATA_DWC_INTMR_NEWFPM |
1248 		 SATA_DWC_INTMR_PMABRTM |
1249 		 SATA_DWC_INTMR_DMATM);
1250 	/*
1251 	 * Unmask the error bits that should trigger an error interrupt by
1252 	 * setting the error mask register.
1253 	 */
1254 	out_le32(&hsdev->sata_dwc_regs->errmr, SATA_DWC_SERROR_ERR_BITS);
1255 
1256 	dev_dbg(host_pvt.dwc_dev, "%s: INTMR = 0x%08x, ERRMR = 0x%08x\n",
1257 		 __func__, in_le32(&hsdev->sata_dwc_regs->intmr),
1258 		in_le32(&hsdev->sata_dwc_regs->errmr));
1259 }
1260 
1261 static void sata_dwc_setup_port(struct ata_ioports *port, unsigned long base)
1262 {
1263 	port->cmd_addr = (void *)base + 0x00;
1264 	port->data_addr = (void *)base + 0x00;
1265 
1266 	port->error_addr = (void *)base + 0x04;
1267 	port->feature_addr = (void *)base + 0x04;
1268 
1269 	port->nsect_addr = (void *)base + 0x08;
1270 
1271 	port->lbal_addr = (void *)base + 0x0c;
1272 	port->lbam_addr = (void *)base + 0x10;
1273 	port->lbah_addr = (void *)base + 0x14;
1274 
1275 	port->device_addr = (void *)base + 0x18;
1276 	port->command_addr = (void *)base + 0x1c;
1277 	port->status_addr = (void *)base + 0x1c;
1278 
1279 	port->altstatus_addr = (void *)base + 0x20;
1280 	port->ctl_addr = (void *)base + 0x20;
1281 }
1282 
1283 /*
1284  * Function : sata_dwc_port_start
1285  * arguments : struct ata_ioports *port
1286  * Return value : returns 0 if success, error code otherwise
1287  * This function allocates the scatter gather LLI table for AHB DMA
1288  */
1289 static int sata_dwc_port_start(struct ata_port *ap)
1290 {
1291 	int err = 0;
1292 	struct sata_dwc_device *hsdev;
1293 	struct sata_dwc_device_port *hsdevp = NULL;
1294 	struct device *pdev;
1295 	int i;
1296 
1297 	hsdev = HSDEV_FROM_AP(ap);
1298 
1299 	dev_dbg(ap->dev, "%s: port_no=%d\n", __func__, ap->port_no);
1300 
1301 	hsdev->host = ap->host;
1302 	pdev = ap->host->dev;
1303 	if (!pdev) {
1304 		dev_err(ap->dev, "%s: no ap->host->dev\n", __func__);
1305 		err = -ENODEV;
1306 		goto CLEANUP;
1307 	}
1308 
1309 	/* Allocate Port Struct */
1310 	hsdevp = kzalloc(sizeof(*hsdevp), GFP_KERNEL);
1311 	if (!hsdevp) {
1312 		dev_err(ap->dev, "%s: kmalloc failed for hsdevp\n", __func__);
1313 		err = -ENOMEM;
1314 		goto CLEANUP;
1315 	}
1316 	hsdevp->hsdev = hsdev;
1317 
1318 	for (i = 0; i < SATA_DWC_QCMD_MAX; i++)
1319 		hsdevp->cmd_issued[i] = SATA_DWC_CMD_ISSUED_NOT;
1320 
1321 	ap->bmdma_prd = 0;	/* set these so libata doesn't use them */
1322 	ap->bmdma_prd_dma = 0;
1323 
1324 	/*
1325 	 * DMA - Assign scatter gather LLI table. We can't use the libata
1326 	 * version since it's PRD is IDE PCI specific.
1327 	 */
1328 	for (i = 0; i < SATA_DWC_QCMD_MAX; i++) {
1329 		hsdevp->llit[i] = dma_alloc_coherent(pdev,
1330 						     SATA_DWC_DMAC_LLI_TBL_SZ,
1331 						     &(hsdevp->llit_dma[i]),
1332 						     GFP_ATOMIC);
1333 		if (!hsdevp->llit[i]) {
1334 			dev_err(ap->dev, "%s: dma_alloc_coherent failed\n",
1335 				 __func__);
1336 			err = -ENOMEM;
1337 			goto CLEANUP_ALLOC;
1338 		}
1339 	}
1340 
1341 	if (ap->port_no == 0)  {
1342 		dev_dbg(ap->dev, "%s: clearing TXCHEN, RXCHEN in DMAC\n",
1343 			__func__);
1344 		out_le32(&hsdev->sata_dwc_regs->dmacr,
1345 			 SATA_DWC_DMACR_TXRXCH_CLEAR);
1346 
1347 		dev_dbg(ap->dev, "%s: setting burst size in DBTSR\n",
1348 			 __func__);
1349 		out_le32(&hsdev->sata_dwc_regs->dbtsr,
1350 			 (SATA_DWC_DBTSR_MWR(AHB_DMA_BRST_DFLT) |
1351 			  SATA_DWC_DBTSR_MRD(AHB_DMA_BRST_DFLT)));
1352 	}
1353 
1354 	/* Clear any error bits before libata starts issuing commands */
1355 	clear_serror();
1356 	ap->private_data = hsdevp;
1357 	dev_dbg(ap->dev, "%s: done\n", __func__);
1358 	return 0;
1359 
1360 CLEANUP_ALLOC:
1361 	kfree(hsdevp);
1362 CLEANUP:
1363 	dev_dbg(ap->dev, "%s: fail. ap->id = %d\n", __func__, ap->print_id);
1364 	return err;
1365 }
1366 
1367 static void sata_dwc_port_stop(struct ata_port *ap)
1368 {
1369 	int i;
1370 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
1371 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1372 
1373 	dev_dbg(ap->dev, "%s: ap->id = %d\n", __func__, ap->print_id);
1374 
1375 	if (hsdevp && hsdev) {
1376 		/* deallocate LLI table */
1377 		for (i = 0; i < SATA_DWC_QCMD_MAX; i++) {
1378 			dma_free_coherent(ap->host->dev,
1379 					  SATA_DWC_DMAC_LLI_TBL_SZ,
1380 					 hsdevp->llit[i], hsdevp->llit_dma[i]);
1381 		}
1382 
1383 		kfree(hsdevp);
1384 	}
1385 	ap->private_data = NULL;
1386 }
1387 
1388 /*
1389  * Function : sata_dwc_exec_command_by_tag
1390  * arguments : ata_port *ap, ata_taskfile *tf, u8 tag, u32 cmd_issued
1391  * Return value : None
1392  * This function keeps track of individual command tag ids and calls
1393  * ata_exec_command in libata
1394  */
1395 static void sata_dwc_exec_command_by_tag(struct ata_port *ap,
1396 					 struct ata_taskfile *tf,
1397 					 u8 tag, u32 cmd_issued)
1398 {
1399 	unsigned long flags;
1400 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1401 
1402 	dev_dbg(ap->dev, "%s cmd(0x%02x): %s tag=%d\n", __func__, tf->command,
1403 		ata_get_cmd_descript(tf->command), tag);
1404 
1405 	spin_lock_irqsave(&ap->host->lock, flags);
1406 	hsdevp->cmd_issued[tag] = cmd_issued;
1407 	spin_unlock_irqrestore(&ap->host->lock, flags);
1408 	/*
1409 	 * Clear SError before executing a new command.
1410 	 * sata_dwc_scr_write and read can not be used here. Clearing the PM
1411 	 * managed SError register for the disk needs to be done before the
1412 	 * task file is loaded.
1413 	 */
1414 	clear_serror();
1415 	ata_sff_exec_command(ap, tf);
1416 }
1417 
1418 static void sata_dwc_bmdma_setup_by_tag(struct ata_queued_cmd *qc, u8 tag)
1419 {
1420 	sata_dwc_exec_command_by_tag(qc->ap, &qc->tf, tag,
1421 				     SATA_DWC_CMD_ISSUED_PEND);
1422 }
1423 
1424 static void sata_dwc_bmdma_setup(struct ata_queued_cmd *qc)
1425 {
1426 	u8 tag = qc->tag;
1427 
1428 	if (ata_is_ncq(qc->tf.protocol)) {
1429 		dev_dbg(qc->ap->dev, "%s: ap->link.sactive=0x%08x tag=%d\n",
1430 			__func__, qc->ap->link.sactive, tag);
1431 	} else {
1432 		tag = 0;
1433 	}
1434 	sata_dwc_bmdma_setup_by_tag(qc, tag);
1435 }
1436 
1437 static void sata_dwc_bmdma_start_by_tag(struct ata_queued_cmd *qc, u8 tag)
1438 {
1439 	int start_dma;
1440 	u32 reg, dma_chan;
1441 	struct sata_dwc_device *hsdev = HSDEV_FROM_QC(qc);
1442 	struct ata_port *ap = qc->ap;
1443 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1444 	int dir = qc->dma_dir;
1445 	dma_chan = hsdevp->dma_chan[tag];
1446 
1447 	if (hsdevp->cmd_issued[tag] != SATA_DWC_CMD_ISSUED_NOT) {
1448 		start_dma = 1;
1449 		if (dir == DMA_TO_DEVICE)
1450 			hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_TX;
1451 		else
1452 			hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_RX;
1453 	} else {
1454 		dev_err(ap->dev, "%s: Command not pending cmd_issued=%d "
1455 			"(tag=%d) DMA NOT started\n", __func__,
1456 			hsdevp->cmd_issued[tag], tag);
1457 		start_dma = 0;
1458 	}
1459 
1460 	dev_dbg(ap->dev, "%s qc=%p tag: %x cmd: 0x%02x dma_dir: %s "
1461 		"start_dma? %x\n", __func__, qc, tag, qc->tf.command,
1462 		get_dma_dir_descript(qc->dma_dir), start_dma);
1463 	sata_dwc_tf_dump(&(qc->tf));
1464 
1465 	if (start_dma) {
1466 		reg = core_scr_read(SCR_ERROR);
1467 		if (reg & SATA_DWC_SERROR_ERR_BITS) {
1468 			dev_err(ap->dev, "%s: ****** SError=0x%08x ******\n",
1469 				__func__, reg);
1470 		}
1471 
1472 		if (dir == DMA_TO_DEVICE)
1473 			out_le32(&hsdev->sata_dwc_regs->dmacr,
1474 				SATA_DWC_DMACR_TXCHEN);
1475 		else
1476 			out_le32(&hsdev->sata_dwc_regs->dmacr,
1477 				SATA_DWC_DMACR_RXCHEN);
1478 
1479 		/* Enable AHB DMA transfer on the specified channel */
1480 		dma_dwc_xfer_start(dma_chan);
1481 	}
1482 }
1483 
1484 static void sata_dwc_bmdma_start(struct ata_queued_cmd *qc)
1485 {
1486 	u8 tag = qc->tag;
1487 
1488 	if (ata_is_ncq(qc->tf.protocol)) {
1489 		dev_dbg(qc->ap->dev, "%s: ap->link.sactive=0x%08x tag=%d\n",
1490 			__func__, qc->ap->link.sactive, tag);
1491 	} else {
1492 		tag = 0;
1493 	}
1494 	dev_dbg(qc->ap->dev, "%s\n", __func__);
1495 	sata_dwc_bmdma_start_by_tag(qc, tag);
1496 }
1497 
1498 /*
1499  * Function : sata_dwc_qc_prep_by_tag
1500  * arguments : ata_queued_cmd *qc, u8 tag
1501  * Return value : None
1502  * qc_prep for a particular queued command based on tag
1503  */
1504 static void sata_dwc_qc_prep_by_tag(struct ata_queued_cmd *qc, u8 tag)
1505 {
1506 	struct scatterlist *sg = qc->sg;
1507 	struct ata_port *ap = qc->ap;
1508 	int dma_chan;
1509 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
1510 	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
1511 
1512 	dev_dbg(ap->dev, "%s: port=%d dma dir=%s n_elem=%d\n",
1513 		__func__, ap->port_no, get_dma_dir_descript(qc->dma_dir),
1514 		 qc->n_elem);
1515 
1516 	dma_chan = dma_dwc_xfer_setup(sg, qc->n_elem, hsdevp->llit[tag],
1517 				      hsdevp->llit_dma[tag],
1518 				      (void *__iomem)(&hsdev->sata_dwc_regs->\
1519 				      dmadr), qc->dma_dir);
1520 	if (dma_chan < 0) {
1521 		dev_err(ap->dev, "%s: dma_dwc_xfer_setup returns err %d\n",
1522 			__func__, dma_chan);
1523 		return;
1524 	}
1525 	hsdevp->dma_chan[tag] = dma_chan;
1526 }
1527 
1528 static unsigned int sata_dwc_qc_issue(struct ata_queued_cmd *qc)
1529 {
1530 	u32 sactive;
1531 	u8 tag = qc->tag;
1532 	struct ata_port *ap = qc->ap;
1533 
1534 #ifdef DEBUG_NCQ
1535 	if (qc->tag > 0 || ap->link.sactive > 1)
1536 		dev_info(ap->dev, "%s ap id=%d cmd(0x%02x)=%s qc tag=%d "
1537 			 "prot=%s ap active_tag=0x%08x ap sactive=0x%08x\n",
1538 			 __func__, ap->print_id, qc->tf.command,
1539 			 ata_get_cmd_descript(qc->tf.command),
1540 			 qc->tag, get_prot_descript(qc->tf.protocol),
1541 			 ap->link.active_tag, ap->link.sactive);
1542 #endif
1543 
1544 	if (!ata_is_ncq(qc->tf.protocol))
1545 		tag = 0;
1546 	sata_dwc_qc_prep_by_tag(qc, tag);
1547 
1548 	if (ata_is_ncq(qc->tf.protocol)) {
1549 		sactive = core_scr_read(SCR_ACTIVE);
1550 		sactive |= (0x00000001 << tag);
1551 		core_scr_write(SCR_ACTIVE, sactive);
1552 
1553 		dev_dbg(qc->ap->dev, "%s: tag=%d ap->link.sactive = 0x%08x "
1554 			"sactive=0x%08x\n", __func__, tag, qc->ap->link.sactive,
1555 			sactive);
1556 
1557 		ap->ops->sff_tf_load(ap, &qc->tf);
1558 		sata_dwc_exec_command_by_tag(ap, &qc->tf, qc->tag,
1559 					     SATA_DWC_CMD_ISSUED_PEND);
1560 	} else {
1561 		ata_sff_qc_issue(qc);
1562 	}
1563 	return 0;
1564 }
1565 
1566 /*
1567  * Function : sata_dwc_qc_prep
1568  * arguments : ata_queued_cmd *qc
1569  * Return value : None
1570  * qc_prep for a particular queued command
1571  */
1572 
1573 static void sata_dwc_qc_prep(struct ata_queued_cmd *qc)
1574 {
1575 	if ((qc->dma_dir == DMA_NONE) || (qc->tf.protocol == ATA_PROT_PIO))
1576 		return;
1577 
1578 #ifdef DEBUG_NCQ
1579 	if (qc->tag > 0)
1580 		dev_info(qc->ap->dev, "%s: qc->tag=%d ap->active_tag=0x%08x\n",
1581 			 __func__, qc->tag, qc->ap->link.active_tag);
1582 
1583 	return ;
1584 #endif
1585 }
1586 
1587 static void sata_dwc_error_handler(struct ata_port *ap)
1588 {
1589 	ata_sff_error_handler(ap);
1590 }
1591 
1592 int sata_dwc_hardreset(struct ata_link *link, unsigned int *class,
1593 			unsigned long deadline)
1594 {
1595 	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(link->ap);
1596 	int ret;
1597 
1598 	ret = sata_sff_hardreset(link, class, deadline);
1599 
1600 	sata_dwc_enable_interrupts(hsdev);
1601 
1602 	/* Reconfigure the DMA control register */
1603 	out_le32(&hsdev->sata_dwc_regs->dmacr,
1604 		 SATA_DWC_DMACR_TXRXCH_CLEAR);
1605 
1606 	/* Reconfigure the DMA Burst Transaction Size register */
1607 	out_le32(&hsdev->sata_dwc_regs->dbtsr,
1608 		 SATA_DWC_DBTSR_MWR(AHB_DMA_BRST_DFLT) |
1609 		 SATA_DWC_DBTSR_MRD(AHB_DMA_BRST_DFLT));
1610 
1611 	return ret;
1612 }
1613 
1614 /*
1615  * scsi mid-layer and libata interface structures
1616  */
1617 static struct scsi_host_template sata_dwc_sht = {
1618 	ATA_NCQ_SHT(DRV_NAME),
1619 	/*
1620 	 * test-only: Currently this driver doesn't handle NCQ
1621 	 * correctly. We enable NCQ but set the queue depth to a
1622 	 * max of 1. This will get fixed in in a future release.
1623 	 */
1624 	.sg_tablesize		= LIBATA_MAX_PRD,
1625 	.can_queue		= ATA_DEF_QUEUE,	/* ATA_MAX_QUEUE */
1626 	.dma_boundary		= ATA_DMA_BOUNDARY,
1627 };
1628 
1629 static struct ata_port_operations sata_dwc_ops = {
1630 	.inherits		= &ata_sff_port_ops,
1631 
1632 	.error_handler		= sata_dwc_error_handler,
1633 	.hardreset		= sata_dwc_hardreset,
1634 
1635 	.qc_prep		= sata_dwc_qc_prep,
1636 	.qc_issue		= sata_dwc_qc_issue,
1637 
1638 	.scr_read		= sata_dwc_scr_read,
1639 	.scr_write		= sata_dwc_scr_write,
1640 
1641 	.port_start		= sata_dwc_port_start,
1642 	.port_stop		= sata_dwc_port_stop,
1643 
1644 	.bmdma_setup		= sata_dwc_bmdma_setup,
1645 	.bmdma_start		= sata_dwc_bmdma_start,
1646 };
1647 
1648 static const struct ata_port_info sata_dwc_port_info[] = {
1649 	{
1650 		.flags		= ATA_FLAG_SATA | ATA_FLAG_NCQ,
1651 		.pio_mask	= ATA_PIO4,
1652 		.udma_mask	= ATA_UDMA6,
1653 		.port_ops	= &sata_dwc_ops,
1654 	},
1655 };
1656 
1657 static int sata_dwc_probe(struct platform_device *ofdev)
1658 {
1659 	struct sata_dwc_device *hsdev;
1660 	u32 idr, versionr;
1661 	char *ver = (char *)&versionr;
1662 	u8 *base = NULL;
1663 	int err = 0;
1664 	int irq, rc;
1665 	struct ata_host *host;
1666 	struct ata_port_info pi = sata_dwc_port_info[0];
1667 	const struct ata_port_info *ppi[] = { &pi, NULL };
1668 	struct device_node *np = ofdev->dev.of_node;
1669 	u32 dma_chan;
1670 
1671 	/* Allocate DWC SATA device */
1672 	hsdev = kzalloc(sizeof(*hsdev), GFP_KERNEL);
1673 	if (hsdev == NULL) {
1674 		dev_err(&ofdev->dev, "kmalloc failed for hsdev\n");
1675 		err = -ENOMEM;
1676 		goto error;
1677 	}
1678 
1679 	if (of_property_read_u32(np, "dma-channel", &dma_chan)) {
1680 		dev_warn(&ofdev->dev, "no dma-channel property set."
1681 			 " Use channel 0\n");
1682 		dma_chan = 0;
1683 	}
1684 	host_pvt.dma_channel = dma_chan;
1685 
1686 	/* Ioremap SATA registers */
1687 	base = of_iomap(ofdev->dev.of_node, 0);
1688 	if (!base) {
1689 		dev_err(&ofdev->dev, "ioremap failed for SATA register"
1690 			" address\n");
1691 		err = -ENODEV;
1692 		goto error_kmalloc;
1693 	}
1694 	hsdev->reg_base = base;
1695 	dev_dbg(&ofdev->dev, "ioremap done for SATA register address\n");
1696 
1697 	/* Synopsys DWC SATA specific Registers */
1698 	hsdev->sata_dwc_regs = (void *__iomem)(base + SATA_DWC_REG_OFFSET);
1699 
1700 	/* Allocate and fill host */
1701 	host = ata_host_alloc_pinfo(&ofdev->dev, ppi, SATA_DWC_MAX_PORTS);
1702 	if (!host) {
1703 		dev_err(&ofdev->dev, "ata_host_alloc_pinfo failed\n");
1704 		err = -ENOMEM;
1705 		goto error_iomap;
1706 	}
1707 
1708 	host->private_data = hsdev;
1709 
1710 	/* Setup port */
1711 	host->ports[0]->ioaddr.cmd_addr = base;
1712 	host->ports[0]->ioaddr.scr_addr = base + SATA_DWC_SCR_OFFSET;
1713 	host_pvt.scr_addr_sstatus = base + SATA_DWC_SCR_OFFSET;
1714 	sata_dwc_setup_port(&host->ports[0]->ioaddr, (unsigned long)base);
1715 
1716 	/* Read the ID and Version Registers */
1717 	idr = in_le32(&hsdev->sata_dwc_regs->idr);
1718 	versionr = in_le32(&hsdev->sata_dwc_regs->versionr);
1719 	dev_notice(&ofdev->dev, "id %d, controller version %c.%c%c\n",
1720 		   idr, ver[0], ver[1], ver[2]);
1721 
1722 	/* Get SATA DMA interrupt number */
1723 	irq = irq_of_parse_and_map(ofdev->dev.of_node, 1);
1724 	if (irq == NO_IRQ) {
1725 		dev_err(&ofdev->dev, "no SATA DMA irq\n");
1726 		err = -ENODEV;
1727 		goto error_out;
1728 	}
1729 
1730 	/* Get physical SATA DMA register base address */
1731 	host_pvt.sata_dma_regs = of_iomap(ofdev->dev.of_node, 1);
1732 	if (!(host_pvt.sata_dma_regs)) {
1733 		dev_err(&ofdev->dev, "ioremap failed for AHBDMA register"
1734 			" address\n");
1735 		err = -ENODEV;
1736 		goto error_out;
1737 	}
1738 
1739 	/* Save dev for later use in dev_xxx() routines */
1740 	host_pvt.dwc_dev = &ofdev->dev;
1741 
1742 	/* Initialize AHB DMAC */
1743 	dma_dwc_init(hsdev, irq);
1744 
1745 	/* Enable SATA Interrupts */
1746 	sata_dwc_enable_interrupts(hsdev);
1747 
1748 	/* Get SATA interrupt number */
1749 	irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
1750 	if (irq == NO_IRQ) {
1751 		dev_err(&ofdev->dev, "no SATA DMA irq\n");
1752 		err = -ENODEV;
1753 		goto error_out;
1754 	}
1755 
1756 	/*
1757 	 * Now, register with libATA core, this will also initiate the
1758 	 * device discovery process, invoking our port_start() handler &
1759 	 * error_handler() to execute a dummy Softreset EH session
1760 	 */
1761 	rc = ata_host_activate(host, irq, sata_dwc_isr, 0, &sata_dwc_sht);
1762 
1763 	if (rc != 0)
1764 		dev_err(&ofdev->dev, "failed to activate host");
1765 
1766 	dev_set_drvdata(&ofdev->dev, host);
1767 	return 0;
1768 
1769 error_out:
1770 	/* Free SATA DMA resources */
1771 	dma_dwc_exit(hsdev);
1772 
1773 error_iomap:
1774 	iounmap(base);
1775 error_kmalloc:
1776 	kfree(hsdev);
1777 error:
1778 	return err;
1779 }
1780 
1781 static int sata_dwc_remove(struct platform_device *ofdev)
1782 {
1783 	struct device *dev = &ofdev->dev;
1784 	struct ata_host *host = dev_get_drvdata(dev);
1785 	struct sata_dwc_device *hsdev = host->private_data;
1786 
1787 	ata_host_detach(host);
1788 	dev_set_drvdata(dev, NULL);
1789 
1790 	/* Free SATA DMA resources */
1791 	dma_dwc_exit(hsdev);
1792 
1793 	iounmap(hsdev->reg_base);
1794 	kfree(hsdev);
1795 	kfree(host);
1796 	dev_dbg(&ofdev->dev, "done\n");
1797 	return 0;
1798 }
1799 
1800 static const struct of_device_id sata_dwc_match[] = {
1801 	{ .compatible = "amcc,sata-460ex", },
1802 	{}
1803 };
1804 MODULE_DEVICE_TABLE(of, sata_dwc_match);
1805 
1806 static struct platform_driver sata_dwc_driver = {
1807 	.driver = {
1808 		.name = DRV_NAME,
1809 		.owner = THIS_MODULE,
1810 		.of_match_table = sata_dwc_match,
1811 	},
1812 	.probe = sata_dwc_probe,
1813 	.remove = sata_dwc_remove,
1814 };
1815 
1816 module_platform_driver(sata_dwc_driver);
1817 
1818 MODULE_LICENSE("GPL");
1819 MODULE_AUTHOR("Mark Miesfeld <mmiesfeld@amcc.com>");
1820 MODULE_DESCRIPTION("DesignWare Cores SATA controller low lever driver");
1821 MODULE_VERSION(DRV_VERSION);
1822