xref: /openbmc/linux/drivers/ata/pata_mpc52xx.c (revision f4356947)
1 /*
2  * drivers/ata/pata_mpc52xx.c
3  *
4  * libata driver for the Freescale MPC52xx on-chip IDE interface
5  *
6  * Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com>
7  * Copyright (C) 2003 Mipsys - Benjamin Herrenschmidt
8  *
9  * UDMA support based on patches by Freescale (Bernard Kuhn, John Rigby),
10  * Domen Puncer and Tim Yamin.
11  *
12  * This file is licensed under the terms of the GNU General Public License
13  * version 2. This program is licensed "as is" without any warranty of any
14  * kind, whether express or implied.
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/gfp.h>
20 #include <linux/delay.h>
21 #include <linux/libata.h>
22 #include <linux/of_address.h>
23 #include <linux/of_irq.h>
24 #include <linux/of_platform.h>
25 #include <linux/types.h>
26 
27 #include <asm/cacheflush.h>
28 #include <asm/mpc52xx.h>
29 
30 #include <linux/fsl/bestcomm/bestcomm.h>
31 #include <linux/fsl/bestcomm/bestcomm_priv.h>
32 #include <linux/fsl/bestcomm/ata.h>
33 
34 #define DRV_NAME	"mpc52xx_ata"
35 
36 /* Private structures used by the driver */
37 struct mpc52xx_ata_timings {
38 	u32	pio1;
39 	u32	pio2;
40 	u32	mdma1;
41 	u32	mdma2;
42 	u32	udma1;
43 	u32	udma2;
44 	u32	udma3;
45 	u32	udma4;
46 	u32	udma5;
47 	int	using_udma;
48 };
49 
50 struct mpc52xx_ata_priv {
51 	unsigned int			ipb_period;
52 	struct mpc52xx_ata __iomem	*ata_regs;
53 	phys_addr_t			ata_regs_pa;
54 	int				ata_irq;
55 	struct mpc52xx_ata_timings	timings[2];
56 	int				csel;
57 
58 	/* DMA */
59 	struct bcom_task		*dmatsk;
60 	const struct udmaspec		*udmaspec;
61 	const struct mdmaspec		*mdmaspec;
62 	int 				mpc52xx_ata_dma_last_write;
63 	int				waiting_for_dma;
64 };
65 
66 
67 /* ATAPI-4 PIO specs (in ns) */
68 static const u16 ataspec_t0[5]		= {600, 383, 240, 180, 120};
69 static const u16 ataspec_t1[5]		= { 70,  50,  30,  30,  25};
70 static const u16 ataspec_t2_8[5]	= {290, 290, 290,  80,  70};
71 static const u16 ataspec_t2_16[5]	= {165, 125, 100,  80,  70};
72 static const u16 ataspec_t2i[5]		= {  0,   0,   0,  70,  25};
73 static const u16 ataspec_t4[5]		= { 30,  20,  15,  10,  10};
74 static const u16 ataspec_ta[5]		= { 35,  35,  35,  35,  35};
75 
76 #define CALC_CLKCYC(c,v) ((((v)+(c)-1)/(c)))
77 
78 /* ======================================================================== */
79 
80 /* ATAPI-4 MDMA specs (in clocks) */
81 struct mdmaspec {
82 	u8 t0M;
83 	u8 td;
84 	u8 th;
85 	u8 tj;
86 	u8 tkw;
87 	u8 tm;
88 	u8 tn;
89 };
90 
91 static const struct mdmaspec mdmaspec66[3] = {
92 	{ .t0M = 32, .td = 15, .th = 2, .tj = 2, .tkw = 15, .tm = 4, .tn = 1 },
93 	{ .t0M = 10, .td = 6,  .th = 1, .tj = 1, .tkw = 4,  .tm = 2, .tn = 1 },
94 	{ .t0M = 8,  .td = 5,  .th = 1, .tj = 1, .tkw = 2,  .tm = 2, .tn = 1 },
95 };
96 
97 static const struct mdmaspec mdmaspec132[3] = {
98 	{ .t0M = 64, .td = 29, .th = 3, .tj = 3, .tkw = 29, .tm = 7, .tn = 2 },
99 	{ .t0M = 20, .td = 11, .th = 2, .tj = 1, .tkw = 7,  .tm = 4, .tn = 1 },
100 	{ .t0M = 16, .td = 10, .th = 2, .tj = 1, .tkw = 4,  .tm = 4, .tn = 1 },
101 };
102 
103 /* ATAPI-4 UDMA specs (in clocks) */
104 struct udmaspec {
105 	u8 tcyc;
106 	u8 t2cyc;
107 	u8 tds;
108 	u8 tdh;
109 	u8 tdvs;
110 	u8 tdvh;
111 	u8 tfs;
112 	u8 tli;
113 	u8 tmli;
114 	u8 taz;
115 	u8 tzah;
116 	u8 tenv;
117 	u8 tsr;
118 	u8 trfs;
119 	u8 trp;
120 	u8 tack;
121 	u8 tss;
122 };
123 
124 static const struct udmaspec udmaspec66[6] = {
125 	{ .tcyc = 8,  .t2cyc = 16, .tds  = 1,  .tdh  = 1, .tdvs = 5,  .tdvh = 1,
126 	  .tfs  = 16, .tli   = 10, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
127 	  .tsr  = 3,  .trfs  = 5,  .trp  = 11, .tack = 2, .tss  = 4,
128 	},
129 	{ .tcyc = 5,  .t2cyc = 11, .tds  = 1,  .tdh  = 1, .tdvs = 4,  .tdvh = 1,
130 	  .tfs  = 14, .tli   = 10, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
131 	  .tsr  = 2,  .trfs  = 5,  .trp  = 9,  .tack = 2, .tss  = 4,
132 	},
133 	{ .tcyc = 4,  .t2cyc = 8,  .tds  = 1,  .tdh  = 1, .tdvs = 3,  .tdvh = 1,
134 	  .tfs  = 12, .tli   = 10, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
135 	  .tsr  = 2,  .trfs  = 4,  .trp  = 7,  .tack = 2, .tss  = 4,
136 	},
137 	{ .tcyc = 3,  .t2cyc = 6,  .tds  = 1,  .tdh  = 1, .tdvs = 2,  .tdvh = 1,
138 	  .tfs  = 9,  .tli   = 7,  .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
139 	  .tsr  = 2,  .trfs  = 4,  .trp  = 7,  .tack = 2, .tss  = 4,
140 	},
141 	{ .tcyc = 2,  .t2cyc = 4,  .tds  = 1,  .tdh  = 1, .tdvs = 1,  .tdvh = 1,
142 	  .tfs  = 8,  .tli   = 8,  .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
143 	  .tsr  = 2,  .trfs  = 4,  .trp  = 7,  .tack = 2, .tss  = 4,
144 	},
145 	{ .tcyc = 2,  .t2cyc = 2,  .tds  = 1,  .tdh  = 1, .tdvs = 1,  .tdvh = 1,
146 	  .tfs  = 6,  .tli   = 5,  .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
147 	  .tsr  = 2,  .trfs  = 4,  .trp  = 6,  .tack = 2, .tss  = 4,
148 	},
149 };
150 
151 static const struct udmaspec udmaspec132[6] = {
152 	{ .tcyc = 15, .t2cyc = 31, .tds  = 2,  .tdh  = 1, .tdvs = 10, .tdvh = 1,
153 	  .tfs  = 30, .tli   = 20, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
154 	  .tsr  = 7,  .trfs  = 10, .trp  = 22, .tack = 3, .tss  = 7,
155 	},
156 	{ .tcyc = 10, .t2cyc = 21, .tds  = 2,  .tdh  = 1, .tdvs = 7,  .tdvh = 1,
157 	  .tfs  = 27, .tli   = 20, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
158 	  .tsr  = 4,  .trfs  = 10, .trp  = 17, .tack = 3, .tss  = 7,
159 	},
160 	{ .tcyc = 6,  .t2cyc = 12, .tds  = 1,  .tdh  = 1, .tdvs = 5,  .tdvh = 1,
161 	  .tfs  = 23, .tli   = 20, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
162 	  .tsr  = 3,  .trfs  = 8,  .trp  = 14, .tack = 3, .tss  = 7,
163 	},
164 	{ .tcyc = 7,  .t2cyc = 12, .tds  = 1,  .tdh  = 1, .tdvs = 3,  .tdvh = 1,
165 	  .tfs  = 15, .tli   = 13, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
166 	  .tsr  = 3,  .trfs  = 8,  .trp  = 14, .tack = 3, .tss  = 7,
167 	},
168 	{ .tcyc = 2,  .t2cyc = 5,  .tds  = 0,  .tdh  = 0, .tdvs = 1,  .tdvh = 1,
169 	  .tfs  = 16, .tli   = 14, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
170 	  .tsr  = 2,  .trfs  = 7,  .trp  = 13, .tack = 2, .tss  = 6,
171 	},
172 	{ .tcyc = 3,  .t2cyc = 6,  .tds  = 1,  .tdh  = 1, .tdvs = 1,  .tdvh = 1,
173 	  .tfs  = 12, .tli   = 10, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
174 	  .tsr  = 3,  .trfs  = 7,  .trp  = 12, .tack = 3, .tss  = 7,
175 	},
176 };
177 
178 /* ======================================================================== */
179 
180 /* Bit definitions inside the registers */
181 #define MPC52xx_ATA_HOSTCONF_SMR	0x80000000UL /* State machine reset */
182 #define MPC52xx_ATA_HOSTCONF_FR		0x40000000UL /* FIFO Reset */
183 #define MPC52xx_ATA_HOSTCONF_IE		0x02000000UL /* Enable interrupt in PIO */
184 #define MPC52xx_ATA_HOSTCONF_IORDY	0x01000000UL /* Drive supports IORDY protocol */
185 
186 #define MPC52xx_ATA_HOSTSTAT_TIP	0x80000000UL /* Transaction in progress */
187 #define MPC52xx_ATA_HOSTSTAT_UREP	0x40000000UL /* UDMA Read Extended Pause */
188 #define MPC52xx_ATA_HOSTSTAT_RERR	0x02000000UL /* Read Error */
189 #define MPC52xx_ATA_HOSTSTAT_WERR	0x01000000UL /* Write Error */
190 
191 #define MPC52xx_ATA_FIFOSTAT_EMPTY	0x01 /* FIFO Empty */
192 #define MPC52xx_ATA_FIFOSTAT_ERROR	0x40 /* FIFO Error */
193 
194 #define MPC52xx_ATA_DMAMODE_WRITE	0x01 /* Write DMA */
195 #define MPC52xx_ATA_DMAMODE_READ	0x02 /* Read DMA */
196 #define MPC52xx_ATA_DMAMODE_UDMA	0x04 /* UDMA enabled */
197 #define MPC52xx_ATA_DMAMODE_IE		0x08 /* Enable drive interrupt to CPU in DMA mode */
198 #define MPC52xx_ATA_DMAMODE_FE		0x10 /* FIFO Flush enable in Rx mode */
199 #define MPC52xx_ATA_DMAMODE_FR		0x20 /* FIFO Reset */
200 #define MPC52xx_ATA_DMAMODE_HUT		0x40 /* Host UDMA burst terminate */
201 
202 #define MAX_DMA_BUFFERS 128
203 #define MAX_DMA_BUFFER_SIZE 0x20000u
204 
205 /* Structure of the hardware registers */
206 struct mpc52xx_ata {
207 
208 	/* Host interface registers */
209 	u32 config;		/* ATA + 0x00 Host configuration */
210 	u32 host_status;	/* ATA + 0x04 Host controller status */
211 	u32 pio1;		/* ATA + 0x08 PIO Timing 1 */
212 	u32 pio2;		/* ATA + 0x0c PIO Timing 2 */
213 	u32 mdma1;		/* ATA + 0x10 MDMA Timing 1 */
214 	u32 mdma2;		/* ATA + 0x14 MDMA Timing 2 */
215 	u32 udma1;		/* ATA + 0x18 UDMA Timing 1 */
216 	u32 udma2;		/* ATA + 0x1c UDMA Timing 2 */
217 	u32 udma3;		/* ATA + 0x20 UDMA Timing 3 */
218 	u32 udma4;		/* ATA + 0x24 UDMA Timing 4 */
219 	u32 udma5;		/* ATA + 0x28 UDMA Timing 5 */
220 	u32 share_cnt;		/* ATA + 0x2c ATA share counter */
221 	u32 reserved0[3];
222 
223 	/* FIFO registers */
224 	u32 fifo_data;		/* ATA + 0x3c */
225 	u8  fifo_status_frame;	/* ATA + 0x40 */
226 	u8  fifo_status;	/* ATA + 0x41 */
227 	u16 reserved7[1];
228 	u8  fifo_control;	/* ATA + 0x44 */
229 	u8  reserved8[5];
230 	u16 fifo_alarm;		/* ATA + 0x4a */
231 	u16 reserved9;
232 	u16 fifo_rdp;		/* ATA + 0x4e */
233 	u16 reserved10;
234 	u16 fifo_wrp;		/* ATA + 0x52 */
235 	u16 reserved11;
236 	u16 fifo_lfrdp;		/* ATA + 0x56 */
237 	u16 reserved12;
238 	u16 fifo_lfwrp;		/* ATA + 0x5a */
239 
240 	/* Drive TaskFile registers */
241 	u8  tf_control;		/* ATA + 0x5c TASKFILE Control/Alt Status */
242 	u8  reserved13[3];
243 	u16 tf_data;		/* ATA + 0x60 TASKFILE Data */
244 	u16 reserved14;
245 	u8  tf_features;	/* ATA + 0x64 TASKFILE Features/Error */
246 	u8  reserved15[3];
247 	u8  tf_sec_count;	/* ATA + 0x68 TASKFILE Sector Count */
248 	u8  reserved16[3];
249 	u8  tf_sec_num;		/* ATA + 0x6c TASKFILE Sector Number */
250 	u8  reserved17[3];
251 	u8  tf_cyl_low;		/* ATA + 0x70 TASKFILE Cylinder Low */
252 	u8  reserved18[3];
253 	u8  tf_cyl_high;	/* ATA + 0x74 TASKFILE Cylinder High */
254 	u8  reserved19[3];
255 	u8  tf_dev_head;	/* ATA + 0x78 TASKFILE Device/Head */
256 	u8  reserved20[3];
257 	u8  tf_command;		/* ATA + 0x7c TASKFILE Command/Status */
258 	u8  dma_mode;		/* ATA + 0x7d ATA Host DMA Mode configuration */
259 	u8  reserved21[2];
260 };
261 
262 
263 /* ======================================================================== */
264 /* Aux fns                                                                  */
265 /* ======================================================================== */
266 
267 
268 /* MPC52xx low level hw control */
269 static int
270 mpc52xx_ata_compute_pio_timings(struct mpc52xx_ata_priv *priv, int dev, int pio)
271 {
272 	struct mpc52xx_ata_timings *timing = &priv->timings[dev];
273 	unsigned int ipb_period = priv->ipb_period;
274 	u32 t0, t1, t2_8, t2_16, t2i, t4, ta;
275 
276 	if ((pio < 0) || (pio > 4))
277 		return -EINVAL;
278 
279 	t0	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t0[pio]);
280 	t1	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t1[pio]);
281 	t2_8	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t2_8[pio]);
282 	t2_16	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t2_16[pio]);
283 	t2i	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t2i[pio]);
284 	t4	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t4[pio]);
285 	ta	= CALC_CLKCYC(ipb_period, 1000 * ataspec_ta[pio]);
286 
287 	timing->pio1 = (t0 << 24) | (t2_8 << 16) | (t2_16 << 8) | (t2i);
288 	timing->pio2 = (t4 << 24) | (t1 << 16) | (ta << 8);
289 
290 	return 0;
291 }
292 
293 static int
294 mpc52xx_ata_compute_mdma_timings(struct mpc52xx_ata_priv *priv, int dev,
295 				 int speed)
296 {
297 	struct mpc52xx_ata_timings *t = &priv->timings[dev];
298 	const struct mdmaspec *s = &priv->mdmaspec[speed];
299 
300 	if (speed < 0 || speed > 2)
301 		return -EINVAL;
302 
303 	t->mdma1 = ((u32)s->t0M << 24) | ((u32)s->td << 16) | ((u32)s->tkw << 8) | s->tm;
304 	t->mdma2 = ((u32)s->th << 24) | ((u32)s->tj << 16) | ((u32)s->tn << 8);
305 	t->using_udma = 0;
306 
307 	return 0;
308 }
309 
310 static int
311 mpc52xx_ata_compute_udma_timings(struct mpc52xx_ata_priv *priv, int dev,
312 				 int speed)
313 {
314 	struct mpc52xx_ata_timings *t = &priv->timings[dev];
315 	const struct udmaspec *s = &priv->udmaspec[speed];
316 
317 	if (speed < 0 || speed > 2)
318 		return -EINVAL;
319 
320 	t->udma1 = ((u32)s->t2cyc << 24) | ((u32)s->tcyc << 16) | ((u32)s->tds << 8) | s->tdh;
321 	t->udma2 = ((u32)s->tdvs << 24) | ((u32)s->tdvh << 16) | ((u32)s->tfs << 8) | s->tli;
322 	t->udma3 = ((u32)s->tmli << 24) | ((u32)s->taz << 16) | ((u32)s->tenv << 8) | s->tsr;
323 	t->udma4 = ((u32)s->tss << 24) | ((u32)s->trfs << 16) | ((u32)s->trp << 8) | s->tack;
324 	t->udma5 = (u32)s->tzah << 24;
325 	t->using_udma = 1;
326 
327 	return 0;
328 }
329 
330 static void
331 mpc52xx_ata_apply_timings(struct mpc52xx_ata_priv *priv, int device)
332 {
333 	struct mpc52xx_ata __iomem *regs = priv->ata_regs;
334 	struct mpc52xx_ata_timings *timing = &priv->timings[device];
335 
336 	out_be32(&regs->pio1,  timing->pio1);
337 	out_be32(&regs->pio2,  timing->pio2);
338 	out_be32(&regs->mdma1, timing->mdma1);
339 	out_be32(&regs->mdma2, timing->mdma2);
340 	out_be32(&regs->udma1, timing->udma1);
341 	out_be32(&regs->udma2, timing->udma2);
342 	out_be32(&regs->udma3, timing->udma3);
343 	out_be32(&regs->udma4, timing->udma4);
344 	out_be32(&regs->udma5, timing->udma5);
345 	priv->csel = device;
346 }
347 
348 static int
349 mpc52xx_ata_hw_init(struct mpc52xx_ata_priv *priv)
350 {
351 	struct mpc52xx_ata __iomem *regs = priv->ata_regs;
352 	int tslot;
353 
354 	/* Clear share_cnt (all sample code do this ...) */
355 	out_be32(&regs->share_cnt, 0);
356 
357 	/* Configure and reset host */
358 	out_be32(&regs->config,
359 			MPC52xx_ATA_HOSTCONF_IE |
360 			MPC52xx_ATA_HOSTCONF_IORDY |
361 			MPC52xx_ATA_HOSTCONF_SMR |
362 			MPC52xx_ATA_HOSTCONF_FR);
363 
364 	udelay(10);
365 
366 	out_be32(&regs->config,
367 			MPC52xx_ATA_HOSTCONF_IE |
368 			MPC52xx_ATA_HOSTCONF_IORDY);
369 
370 	/* Set the time slot to 1us */
371 	tslot = CALC_CLKCYC(priv->ipb_period, 1000000);
372 	out_be32(&regs->share_cnt, tslot << 16);
373 
374 	/* Init timings to PIO0 */
375 	memset(priv->timings, 0x00, 2*sizeof(struct mpc52xx_ata_timings));
376 
377 	mpc52xx_ata_compute_pio_timings(priv, 0, 0);
378 	mpc52xx_ata_compute_pio_timings(priv, 1, 0);
379 
380 	mpc52xx_ata_apply_timings(priv, 0);
381 
382 	return 0;
383 }
384 
385 
386 /* ======================================================================== */
387 /* libata driver                                                            */
388 /* ======================================================================== */
389 
390 static void
391 mpc52xx_ata_set_piomode(struct ata_port *ap, struct ata_device *adev)
392 {
393 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
394 	int pio, rv;
395 
396 	pio = adev->pio_mode - XFER_PIO_0;
397 
398 	rv = mpc52xx_ata_compute_pio_timings(priv, adev->devno, pio);
399 
400 	if (rv) {
401 		dev_err(ap->dev, "error: invalid PIO mode: %d\n", pio);
402 		return;
403 	}
404 
405 	mpc52xx_ata_apply_timings(priv, adev->devno);
406 }
407 
408 static void
409 mpc52xx_ata_set_dmamode(struct ata_port *ap, struct ata_device *adev)
410 {
411 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
412 	int rv;
413 
414 	if (adev->dma_mode >= XFER_UDMA_0) {
415 		int dma = adev->dma_mode - XFER_UDMA_0;
416 		rv = mpc52xx_ata_compute_udma_timings(priv, adev->devno, dma);
417 	} else {
418 		int dma = adev->dma_mode - XFER_MW_DMA_0;
419 		rv = mpc52xx_ata_compute_mdma_timings(priv, adev->devno, dma);
420 	}
421 
422 	if (rv) {
423 		dev_alert(ap->dev,
424 			"Trying to select invalid DMA mode %d\n",
425 			adev->dma_mode);
426 		return;
427 	}
428 
429 	mpc52xx_ata_apply_timings(priv, adev->devno);
430 }
431 
432 static void
433 mpc52xx_ata_dev_select(struct ata_port *ap, unsigned int device)
434 {
435 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
436 
437 	if (device != priv->csel)
438 		mpc52xx_ata_apply_timings(priv, device);
439 
440 	ata_sff_dev_select(ap, device);
441 }
442 
443 static int
444 mpc52xx_ata_build_dmatable(struct ata_queued_cmd *qc)
445 {
446 	struct ata_port *ap = qc->ap;
447 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
448 	struct bcom_ata_bd *bd;
449 	unsigned int read = !(qc->tf.flags & ATA_TFLAG_WRITE), si;
450 	struct scatterlist *sg;
451 	int count = 0;
452 
453 	if (read)
454 		bcom_ata_rx_prepare(priv->dmatsk);
455 	else
456 		bcom_ata_tx_prepare(priv->dmatsk);
457 
458 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
459 		dma_addr_t cur_addr = sg_dma_address(sg);
460 		u32 cur_len = sg_dma_len(sg);
461 
462 		while (cur_len) {
463 			unsigned int tc = min(cur_len, MAX_DMA_BUFFER_SIZE);
464 			bd = (struct bcom_ata_bd *)
465 				bcom_prepare_next_buffer(priv->dmatsk);
466 
467 			if (read) {
468 				bd->status = tc;
469 				bd->src_pa = (__force u32) priv->ata_regs_pa +
470 					offsetof(struct mpc52xx_ata, fifo_data);
471 				bd->dst_pa = (__force u32) cur_addr;
472 			} else {
473 				bd->status = tc;
474 				bd->src_pa = (__force u32) cur_addr;
475 				bd->dst_pa = (__force u32) priv->ata_regs_pa +
476 					offsetof(struct mpc52xx_ata, fifo_data);
477 			}
478 
479 			bcom_submit_next_buffer(priv->dmatsk, NULL);
480 
481 			cur_addr += tc;
482 			cur_len -= tc;
483 			count++;
484 
485 			if (count > MAX_DMA_BUFFERS) {
486 				dev_alert(ap->dev, "dma table"
487 					"too small\n");
488 				goto use_pio_instead;
489 			}
490 		}
491 	}
492 	return 1;
493 
494  use_pio_instead:
495 	bcom_ata_reset_bd(priv->dmatsk);
496 	return 0;
497 }
498 
499 static void
500 mpc52xx_bmdma_setup(struct ata_queued_cmd *qc)
501 {
502 	struct ata_port *ap = qc->ap;
503 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
504 	struct mpc52xx_ata __iomem *regs = priv->ata_regs;
505 
506 	unsigned int read = !(qc->tf.flags & ATA_TFLAG_WRITE);
507 	u8 dma_mode;
508 
509 	if (!mpc52xx_ata_build_dmatable(qc))
510 		dev_alert(ap->dev, "%s: %i, return 1?\n",
511 			__func__, __LINE__);
512 
513 	/* Check FIFO is OK... */
514 	if (in_8(&priv->ata_regs->fifo_status) & MPC52xx_ATA_FIFOSTAT_ERROR)
515 		dev_alert(ap->dev, "%s: FIFO error detected: 0x%02x!\n",
516 			__func__, in_8(&priv->ata_regs->fifo_status));
517 
518 	if (read) {
519 		dma_mode = MPC52xx_ATA_DMAMODE_IE | MPC52xx_ATA_DMAMODE_READ |
520 				MPC52xx_ATA_DMAMODE_FE;
521 
522 		/* Setup FIFO if direction changed */
523 		if (priv->mpc52xx_ata_dma_last_write != 0) {
524 			priv->mpc52xx_ata_dma_last_write = 0;
525 
526 			/* Configure FIFO with granularity to 7 */
527 			out_8(&regs->fifo_control, 7);
528 			out_be16(&regs->fifo_alarm, 128);
529 
530 			/* Set FIFO Reset bit (FR) */
531 			out_8(&regs->dma_mode, MPC52xx_ATA_DMAMODE_FR);
532 		}
533 	} else {
534 		dma_mode = MPC52xx_ATA_DMAMODE_IE | MPC52xx_ATA_DMAMODE_WRITE;
535 
536 		/* Setup FIFO if direction changed */
537 		if (priv->mpc52xx_ata_dma_last_write != 1) {
538 			priv->mpc52xx_ata_dma_last_write = 1;
539 
540 			/* Configure FIFO with granularity to 4 */
541 			out_8(&regs->fifo_control, 4);
542 			out_be16(&regs->fifo_alarm, 128);
543 		}
544 	}
545 
546 	if (priv->timings[qc->dev->devno].using_udma)
547 		dma_mode |= MPC52xx_ATA_DMAMODE_UDMA;
548 
549 	out_8(&regs->dma_mode, dma_mode);
550 	priv->waiting_for_dma = ATA_DMA_ACTIVE;
551 
552 	ata_wait_idle(ap);
553 	ap->ops->sff_exec_command(ap, &qc->tf);
554 }
555 
556 static void
557 mpc52xx_bmdma_start(struct ata_queued_cmd *qc)
558 {
559 	struct ata_port *ap = qc->ap;
560 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
561 
562 	bcom_set_task_auto_start(priv->dmatsk->tasknum, priv->dmatsk->tasknum);
563 	bcom_enable(priv->dmatsk);
564 }
565 
566 static void
567 mpc52xx_bmdma_stop(struct ata_queued_cmd *qc)
568 {
569 	struct ata_port *ap = qc->ap;
570 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
571 
572 	bcom_disable(priv->dmatsk);
573 	bcom_ata_reset_bd(priv->dmatsk);
574 	priv->waiting_for_dma = 0;
575 
576 	/* Check FIFO is OK... */
577 	if (in_8(&priv->ata_regs->fifo_status) & MPC52xx_ATA_FIFOSTAT_ERROR)
578 		dev_alert(ap->dev, "%s: FIFO error detected: 0x%02x!\n",
579 			__func__, in_8(&priv->ata_regs->fifo_status));
580 }
581 
582 static u8
583 mpc52xx_bmdma_status(struct ata_port *ap)
584 {
585 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
586 
587 	/* Check FIFO is OK... */
588 	if (in_8(&priv->ata_regs->fifo_status) & MPC52xx_ATA_FIFOSTAT_ERROR) {
589 		dev_alert(ap->dev, "%s: FIFO error detected: 0x%02x!\n",
590 			__func__, in_8(&priv->ata_regs->fifo_status));
591 		return priv->waiting_for_dma | ATA_DMA_ERR;
592 	}
593 
594 	return priv->waiting_for_dma;
595 }
596 
597 static irqreturn_t
598 mpc52xx_ata_task_irq(int irq, void *vpriv)
599 {
600 	struct mpc52xx_ata_priv *priv = vpriv;
601 	while (bcom_buffer_done(priv->dmatsk))
602 		bcom_retrieve_buffer(priv->dmatsk, NULL, NULL);
603 
604 	priv->waiting_for_dma |= ATA_DMA_INTR;
605 
606 	return IRQ_HANDLED;
607 }
608 
609 static const struct scsi_host_template mpc52xx_ata_sht = {
610 	ATA_PIO_SHT(DRV_NAME),
611 };
612 
613 static struct ata_port_operations mpc52xx_ata_port_ops = {
614 	.inherits		= &ata_bmdma_port_ops,
615 	.sff_dev_select		= mpc52xx_ata_dev_select,
616 	.set_piomode		= mpc52xx_ata_set_piomode,
617 	.set_dmamode		= mpc52xx_ata_set_dmamode,
618 	.bmdma_setup		= mpc52xx_bmdma_setup,
619 	.bmdma_start		= mpc52xx_bmdma_start,
620 	.bmdma_stop		= mpc52xx_bmdma_stop,
621 	.bmdma_status		= mpc52xx_bmdma_status,
622 	.qc_prep		= ata_noop_qc_prep,
623 };
624 
625 static int mpc52xx_ata_init_one(struct device *dev,
626 				struct mpc52xx_ata_priv *priv,
627 				unsigned long raw_ata_regs,
628 				int mwdma_mask, int udma_mask)
629 {
630 	struct ata_host *host;
631 	struct ata_port *ap;
632 	struct ata_ioports *aio;
633 
634 	host = ata_host_alloc(dev, 1);
635 	if (!host)
636 		return -ENOMEM;
637 
638 	ap = host->ports[0];
639 	ap->flags		|= ATA_FLAG_SLAVE_POSS;
640 	ap->pio_mask		= ATA_PIO4;
641 	ap->mwdma_mask		= mwdma_mask;
642 	ap->udma_mask		= udma_mask;
643 	ap->ops			= &mpc52xx_ata_port_ops;
644 	host->private_data	= priv;
645 
646 	aio = &ap->ioaddr;
647 	aio->cmd_addr		= NULL;	/* Don't have a classic reg block */
648 	aio->altstatus_addr	= &priv->ata_regs->tf_control;
649 	aio->ctl_addr		= &priv->ata_regs->tf_control;
650 	aio->data_addr		= &priv->ata_regs->tf_data;
651 	aio->error_addr		= &priv->ata_regs->tf_features;
652 	aio->feature_addr	= &priv->ata_regs->tf_features;
653 	aio->nsect_addr		= &priv->ata_regs->tf_sec_count;
654 	aio->lbal_addr		= &priv->ata_regs->tf_sec_num;
655 	aio->lbam_addr		= &priv->ata_regs->tf_cyl_low;
656 	aio->lbah_addr		= &priv->ata_regs->tf_cyl_high;
657 	aio->device_addr	= &priv->ata_regs->tf_dev_head;
658 	aio->status_addr	= &priv->ata_regs->tf_command;
659 	aio->command_addr	= &priv->ata_regs->tf_command;
660 
661 	ata_port_desc(ap, "ata_regs 0x%lx", raw_ata_regs);
662 
663 	/* activate host */
664 	return ata_host_activate(host, priv->ata_irq, ata_bmdma_interrupt, 0,
665 				 &mpc52xx_ata_sht);
666 }
667 
668 /* ======================================================================== */
669 /* OF Platform driver                                                       */
670 /* ======================================================================== */
671 
672 static int mpc52xx_ata_probe(struct platform_device *op)
673 {
674 	unsigned int ipb_freq;
675 	struct resource res_mem;
676 	int ata_irq = 0;
677 	struct mpc52xx_ata __iomem *ata_regs;
678 	struct mpc52xx_ata_priv *priv = NULL;
679 	int rv, task_irq;
680 	int mwdma_mask = 0, udma_mask = 0;
681 	const __be32 *prop;
682 	int proplen;
683 	struct bcom_task *dmatsk;
684 
685 	/* Get ipb frequency */
686 	ipb_freq = mpc5xxx_get_bus_frequency(&op->dev);
687 	if (!ipb_freq) {
688 		dev_err(&op->dev, "could not determine IPB bus frequency\n");
689 		return -ENODEV;
690 	}
691 
692 	/* Get device base address from device tree, request the region
693 	 * and ioremap it. */
694 	rv = of_address_to_resource(op->dev.of_node, 0, &res_mem);
695 	if (rv) {
696 		dev_err(&op->dev, "could not determine device base address\n");
697 		return rv;
698 	}
699 
700 	if (!devm_request_mem_region(&op->dev, res_mem.start,
701 				     sizeof(*ata_regs), DRV_NAME)) {
702 		dev_err(&op->dev, "error requesting register region\n");
703 		return -EBUSY;
704 	}
705 
706 	ata_regs = devm_ioremap(&op->dev, res_mem.start, sizeof(*ata_regs));
707 	if (!ata_regs) {
708 		dev_err(&op->dev, "error mapping device registers\n");
709 		return -ENOMEM;
710 	}
711 
712 	/*
713 	 * By default, all DMA modes are disabled for the MPC5200.  Some
714 	 * boards don't have the required signals routed to make DMA work.
715 	 * Also, the MPC5200B has a silicon bug that causes data corruption
716 	 * with UDMA if it is used at the same time as the LocalPlus bus.
717 	 *
718 	 * Instead of trying to guess what modes are usable, check the
719 	 * ATA device tree node to find out what DMA modes work on the board.
720 	 * UDMA/MWDMA modes can also be forced by adding "libata.force=<mode>"
721 	 * to the kernel boot parameters.
722 	 *
723 	 * The MPC5200 ATA controller supports MWDMA modes 0, 1 and 2 and
724 	 * UDMA modes 0, 1 and 2.
725 	 */
726 	prop = of_get_property(op->dev.of_node, "mwdma-mode", &proplen);
727 	if ((prop) && (proplen >= 4))
728 		mwdma_mask = ATA_MWDMA2 & ((1 << (*prop + 1)) - 1);
729 	prop = of_get_property(op->dev.of_node, "udma-mode", &proplen);
730 	if ((prop) && (proplen >= 4))
731 		udma_mask = ATA_UDMA2 & ((1 << (*prop + 1)) - 1);
732 
733 	ata_irq = irq_of_parse_and_map(op->dev.of_node, 0);
734 	if (!ata_irq) {
735 		dev_err(&op->dev, "error mapping irq\n");
736 		return -EINVAL;
737 	}
738 
739 	/* Prepare our private structure */
740 	priv = devm_kzalloc(&op->dev, sizeof(*priv), GFP_KERNEL);
741 	if (!priv) {
742 		rv = -ENOMEM;
743 		goto err1;
744 	}
745 
746 	priv->ipb_period = 1000000000 / (ipb_freq / 1000);
747 	priv->ata_regs = ata_regs;
748 	priv->ata_regs_pa = res_mem.start;
749 	priv->ata_irq = ata_irq;
750 	priv->csel = -1;
751 	priv->mpc52xx_ata_dma_last_write = -1;
752 
753 	if (ipb_freq/1000000 == 66) {
754 		priv->mdmaspec = mdmaspec66;
755 		priv->udmaspec = udmaspec66;
756 	} else {
757 		priv->mdmaspec = mdmaspec132;
758 		priv->udmaspec = udmaspec132;
759 	}
760 
761 	/* Allocate a BestComm task for DMA */
762 	dmatsk = bcom_ata_init(MAX_DMA_BUFFERS, MAX_DMA_BUFFER_SIZE);
763 	if (!dmatsk) {
764 		dev_err(&op->dev, "bestcomm initialization failed\n");
765 		rv = -ENOMEM;
766 		goto err1;
767 	}
768 
769 	task_irq = bcom_get_task_irq(dmatsk);
770 	rv = devm_request_irq(&op->dev, task_irq, &mpc52xx_ata_task_irq, 0,
771 				"ATA task", priv);
772 	if (rv) {
773 		dev_err(&op->dev, "error requesting DMA IRQ\n");
774 		goto err2;
775 	}
776 	priv->dmatsk = dmatsk;
777 
778 	/* Init the hw */
779 	rv = mpc52xx_ata_hw_init(priv);
780 	if (rv) {
781 		dev_err(&op->dev, "error initializing hardware\n");
782 		goto err2;
783 	}
784 
785 	/* Register ourselves to libata */
786 	rv = mpc52xx_ata_init_one(&op->dev, priv, res_mem.start,
787 				  mwdma_mask, udma_mask);
788 	if (rv) {
789 		dev_err(&op->dev, "error registering with ATA layer\n");
790 		goto err2;
791 	}
792 
793 	return 0;
794 
795  err2:
796 	irq_dispose_mapping(task_irq);
797 	bcom_ata_release(dmatsk);
798  err1:
799 	irq_dispose_mapping(ata_irq);
800 	return rv;
801 }
802 
803 static int
804 mpc52xx_ata_remove(struct platform_device *op)
805 {
806 	struct ata_host *host = platform_get_drvdata(op);
807 	struct mpc52xx_ata_priv *priv = host->private_data;
808 	int task_irq;
809 
810 	/* Deregister the ATA interface */
811 	ata_platform_remove_one(op);
812 
813 	/* Clean up DMA */
814 	task_irq = bcom_get_task_irq(priv->dmatsk);
815 	irq_dispose_mapping(task_irq);
816 	bcom_ata_release(priv->dmatsk);
817 	irq_dispose_mapping(priv->ata_irq);
818 
819 	return 0;
820 }
821 
822 #ifdef CONFIG_PM_SLEEP
823 static int
824 mpc52xx_ata_suspend(struct platform_device *op, pm_message_t state)
825 {
826 	struct ata_host *host = platform_get_drvdata(op);
827 
828 	ata_host_suspend(host, state);
829 	return 0;
830 }
831 
832 static int
833 mpc52xx_ata_resume(struct platform_device *op)
834 {
835 	struct ata_host *host = platform_get_drvdata(op);
836 	struct mpc52xx_ata_priv *priv = host->private_data;
837 	int rv;
838 
839 	rv = mpc52xx_ata_hw_init(priv);
840 	if (rv) {
841 		dev_err(host->dev, "error initializing hardware\n");
842 		return rv;
843 	}
844 
845 	ata_host_resume(host);
846 
847 	return 0;
848 }
849 #endif
850 
851 static const struct of_device_id mpc52xx_ata_of_match[] = {
852 	{ .compatible = "fsl,mpc5200-ata", },
853 	{ .compatible = "mpc5200-ata", },
854 	{ /* sentinel */ }
855 };
856 
857 
858 static struct platform_driver mpc52xx_ata_of_platform_driver = {
859 	.probe		= mpc52xx_ata_probe,
860 	.remove		= mpc52xx_ata_remove,
861 #ifdef CONFIG_PM_SLEEP
862 	.suspend	= mpc52xx_ata_suspend,
863 	.resume		= mpc52xx_ata_resume,
864 #endif
865 	.driver		= {
866 		.name	= DRV_NAME,
867 		.of_match_table = mpc52xx_ata_of_match,
868 	},
869 };
870 
871 module_platform_driver(mpc52xx_ata_of_platform_driver);
872 
873 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
874 MODULE_DESCRIPTION("Freescale MPC52xx IDE/ATA libata driver");
875 MODULE_LICENSE("GPL");
876 MODULE_DEVICE_TABLE(of, mpc52xx_ata_of_match);
877 
878