xref: /openbmc/linux/drivers/ata/pata_mpc52xx.c (revision db181ce0)
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_platform.h>
23 #include <linux/types.h>
24 
25 #include <asm/cacheflush.h>
26 #include <asm/prom.h>
27 #include <asm/mpc52xx.h>
28 
29 #include <linux/fsl/bestcomm/bestcomm.h>
30 #include <linux/fsl/bestcomm/bestcomm_priv.h>
31 #include <linux/fsl/bestcomm/ata.h>
32 
33 #define DRV_NAME	"mpc52xx_ata"
34 
35 /* Private structures used by the driver */
36 struct mpc52xx_ata_timings {
37 	u32	pio1;
38 	u32	pio2;
39 	u32	mdma1;
40 	u32	mdma2;
41 	u32	udma1;
42 	u32	udma2;
43 	u32	udma3;
44 	u32	udma4;
45 	u32	udma5;
46 	int	using_udma;
47 };
48 
49 struct mpc52xx_ata_priv {
50 	unsigned int			ipb_period;
51 	struct mpc52xx_ata __iomem	*ata_regs;
52 	phys_addr_t			ata_regs_pa;
53 	int				ata_irq;
54 	struct mpc52xx_ata_timings	timings[2];
55 	int				csel;
56 
57 	/* DMA */
58 	struct bcom_task		*dmatsk;
59 	const struct udmaspec		*udmaspec;
60 	const struct mdmaspec		*mdmaspec;
61 	int 				mpc52xx_ata_dma_last_write;
62 	int				waiting_for_dma;
63 };
64 
65 
66 /* ATAPI-4 PIO specs (in ns) */
67 static const u16 ataspec_t0[5]		= {600, 383, 240, 180, 120};
68 static const u16 ataspec_t1[5]		= { 70,  50,  30,  30,  25};
69 static const u16 ataspec_t2_8[5]	= {290, 290, 290,  80,  70};
70 static const u16 ataspec_t2_16[5]	= {165, 125, 100,  80,  70};
71 static const u16 ataspec_t2i[5]		= {  0,   0,   0,  70,  25};
72 static const u16 ataspec_t4[5]		= { 30,  20,  15,  10,  10};
73 static const u16 ataspec_ta[5]		= { 35,  35,  35,  35,  35};
74 
75 #define CALC_CLKCYC(c,v) ((((v)+(c)-1)/(c)))
76 
77 /* ======================================================================== */
78 
79 /* ATAPI-4 MDMA specs (in clocks) */
80 struct mdmaspec {
81 	u8 t0M;
82 	u8 td;
83 	u8 th;
84 	u8 tj;
85 	u8 tkw;
86 	u8 tm;
87 	u8 tn;
88 };
89 
90 static const struct mdmaspec mdmaspec66[3] = {
91 	{ .t0M = 32, .td = 15, .th = 2, .tj = 2, .tkw = 15, .tm = 4, .tn = 1 },
92 	{ .t0M = 10, .td = 6,  .th = 1, .tj = 1, .tkw = 4,  .tm = 2, .tn = 1 },
93 	{ .t0M = 8,  .td = 5,  .th = 1, .tj = 1, .tkw = 2,  .tm = 2, .tn = 1 },
94 };
95 
96 static const struct mdmaspec mdmaspec132[3] = {
97 	{ .t0M = 64, .td = 29, .th = 3, .tj = 3, .tkw = 29, .tm = 7, .tn = 2 },
98 	{ .t0M = 20, .td = 11, .th = 2, .tj = 1, .tkw = 7,  .tm = 4, .tn = 1 },
99 	{ .t0M = 16, .td = 10, .th = 2, .tj = 1, .tkw = 4,  .tm = 4, .tn = 1 },
100 };
101 
102 /* ATAPI-4 UDMA specs (in clocks) */
103 struct udmaspec {
104 	u8 tcyc;
105 	u8 t2cyc;
106 	u8 tds;
107 	u8 tdh;
108 	u8 tdvs;
109 	u8 tdvh;
110 	u8 tfs;
111 	u8 tli;
112 	u8 tmli;
113 	u8 taz;
114 	u8 tzah;
115 	u8 tenv;
116 	u8 tsr;
117 	u8 trfs;
118 	u8 trp;
119 	u8 tack;
120 	u8 tss;
121 };
122 
123 static const struct udmaspec udmaspec66[6] = {
124 	{ .tcyc = 8,  .t2cyc = 16, .tds  = 1,  .tdh  = 1, .tdvs = 5,  .tdvh = 1,
125 	  .tfs  = 16, .tli   = 10, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
126 	  .tsr  = 3,  .trfs  = 5,  .trp  = 11, .tack = 2, .tss  = 4,
127 	},
128 	{ .tcyc = 5,  .t2cyc = 11, .tds  = 1,  .tdh  = 1, .tdvs = 4,  .tdvh = 1,
129 	  .tfs  = 14, .tli   = 10, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
130 	  .tsr  = 2,  .trfs  = 5,  .trp  = 9,  .tack = 2, .tss  = 4,
131 	},
132 	{ .tcyc = 4,  .t2cyc = 8,  .tds  = 1,  .tdh  = 1, .tdvs = 3,  .tdvh = 1,
133 	  .tfs  = 12, .tli   = 10, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
134 	  .tsr  = 2,  .trfs  = 4,  .trp  = 7,  .tack = 2, .tss  = 4,
135 	},
136 	{ .tcyc = 3,  .t2cyc = 6,  .tds  = 1,  .tdh  = 1, .tdvs = 2,  .tdvh = 1,
137 	  .tfs  = 9,  .tli   = 7,  .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
138 	  .tsr  = 2,  .trfs  = 4,  .trp  = 7,  .tack = 2, .tss  = 4,
139 	},
140 	{ .tcyc = 2,  .t2cyc = 4,  .tds  = 1,  .tdh  = 1, .tdvs = 1,  .tdvh = 1,
141 	  .tfs  = 8,  .tli   = 8,  .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
142 	  .tsr  = 2,  .trfs  = 4,  .trp  = 7,  .tack = 2, .tss  = 4,
143 	},
144 	{ .tcyc = 2,  .t2cyc = 2,  .tds  = 1,  .tdh  = 1, .tdvs = 1,  .tdvh = 1,
145 	  .tfs  = 6,  .tli   = 5,  .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
146 	  .tsr  = 2,  .trfs  = 4,  .trp  = 6,  .tack = 2, .tss  = 4,
147 	},
148 };
149 
150 static const struct udmaspec udmaspec132[6] = {
151 	{ .tcyc = 15, .t2cyc = 31, .tds  = 2,  .tdh  = 1, .tdvs = 10, .tdvh = 1,
152 	  .tfs  = 30, .tli   = 20, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
153 	  .tsr  = 7,  .trfs  = 10, .trp  = 22, .tack = 3, .tss  = 7,
154 	},
155 	{ .tcyc = 10, .t2cyc = 21, .tds  = 2,  .tdh  = 1, .tdvs = 7,  .tdvh = 1,
156 	  .tfs  = 27, .tli   = 20, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
157 	  .tsr  = 4,  .trfs  = 10, .trp  = 17, .tack = 3, .tss  = 7,
158 	},
159 	{ .tcyc = 6,  .t2cyc = 12, .tds  = 1,  .tdh  = 1, .tdvs = 5,  .tdvh = 1,
160 	  .tfs  = 23, .tli   = 20, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
161 	  .tsr  = 3,  .trfs  = 8,  .trp  = 14, .tack = 3, .tss  = 7,
162 	},
163 	{ .tcyc = 7,  .t2cyc = 12, .tds  = 1,  .tdh  = 1, .tdvs = 3,  .tdvh = 1,
164 	  .tfs  = 15, .tli   = 13, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
165 	  .tsr  = 3,  .trfs  = 8,  .trp  = 14, .tack = 3, .tss  = 7,
166 	},
167 	{ .tcyc = 2,  .t2cyc = 5,  .tds  = 0,  .tdh  = 0, .tdvs = 1,  .tdvh = 1,
168 	  .tfs  = 16, .tli   = 14, .tmli = 2,  .taz  = 1, .tzah = 2,  .tenv = 2,
169 	  .tsr  = 2,  .trfs  = 7,  .trp  = 13, .tack = 2, .tss  = 6,
170 	},
171 	{ .tcyc = 3,  .t2cyc = 6,  .tds  = 1,  .tdh  = 1, .tdvs = 1,  .tdvh = 1,
172 	  .tfs  = 12, .tli   = 10, .tmli = 3,  .taz  = 2, .tzah = 3,  .tenv = 3,
173 	  .tsr  = 3,  .trfs  = 7,  .trp  = 12, .tack = 3, .tss  = 7,
174 	},
175 };
176 
177 /* ======================================================================== */
178 
179 /* Bit definitions inside the registers */
180 #define MPC52xx_ATA_HOSTCONF_SMR	0x80000000UL /* State machine reset */
181 #define MPC52xx_ATA_HOSTCONF_FR		0x40000000UL /* FIFO Reset */
182 #define MPC52xx_ATA_HOSTCONF_IE		0x02000000UL /* Enable interrupt in PIO */
183 #define MPC52xx_ATA_HOSTCONF_IORDY	0x01000000UL /* Drive supports IORDY protocol */
184 
185 #define MPC52xx_ATA_HOSTSTAT_TIP	0x80000000UL /* Transaction in progress */
186 #define MPC52xx_ATA_HOSTSTAT_UREP	0x40000000UL /* UDMA Read Extended Pause */
187 #define MPC52xx_ATA_HOSTSTAT_RERR	0x02000000UL /* Read Error */
188 #define MPC52xx_ATA_HOSTSTAT_WERR	0x01000000UL /* Write Error */
189 
190 #define MPC52xx_ATA_FIFOSTAT_EMPTY	0x01 /* FIFO Empty */
191 #define MPC52xx_ATA_FIFOSTAT_ERROR	0x40 /* FIFO Error */
192 
193 #define MPC52xx_ATA_DMAMODE_WRITE	0x01 /* Write DMA */
194 #define MPC52xx_ATA_DMAMODE_READ	0x02 /* Read DMA */
195 #define MPC52xx_ATA_DMAMODE_UDMA	0x04 /* UDMA enabled */
196 #define MPC52xx_ATA_DMAMODE_IE		0x08 /* Enable drive interrupt to CPU in DMA mode */
197 #define MPC52xx_ATA_DMAMODE_FE		0x10 /* FIFO Flush enable in Rx mode */
198 #define MPC52xx_ATA_DMAMODE_FR		0x20 /* FIFO Reset */
199 #define MPC52xx_ATA_DMAMODE_HUT		0x40 /* Host UDMA burst terminate */
200 
201 #define MAX_DMA_BUFFERS 128
202 #define MAX_DMA_BUFFER_SIZE 0x20000u
203 
204 /* Structure of the hardware registers */
205 struct mpc52xx_ata {
206 
207 	/* Host interface registers */
208 	u32 config;		/* ATA + 0x00 Host configuration */
209 	u32 host_status;	/* ATA + 0x04 Host controller status */
210 	u32 pio1;		/* ATA + 0x08 PIO Timing 1 */
211 	u32 pio2;		/* ATA + 0x0c PIO Timing 2 */
212 	u32 mdma1;		/* ATA + 0x10 MDMA Timing 1 */
213 	u32 mdma2;		/* ATA + 0x14 MDMA Timing 2 */
214 	u32 udma1;		/* ATA + 0x18 UDMA Timing 1 */
215 	u32 udma2;		/* ATA + 0x1c UDMA Timing 2 */
216 	u32 udma3;		/* ATA + 0x20 UDMA Timing 3 */
217 	u32 udma4;		/* ATA + 0x24 UDMA Timing 4 */
218 	u32 udma5;		/* ATA + 0x28 UDMA Timing 5 */
219 	u32 share_cnt;		/* ATA + 0x2c ATA share counter */
220 	u32 reserved0[3];
221 
222 	/* FIFO registers */
223 	u32 fifo_data;		/* ATA + 0x3c */
224 	u8  fifo_status_frame;	/* ATA + 0x40 */
225 	u8  fifo_status;	/* ATA + 0x41 */
226 	u16 reserved7[1];
227 	u8  fifo_control;	/* ATA + 0x44 */
228 	u8  reserved8[5];
229 	u16 fifo_alarm;		/* ATA + 0x4a */
230 	u16 reserved9;
231 	u16 fifo_rdp;		/* ATA + 0x4e */
232 	u16 reserved10;
233 	u16 fifo_wrp;		/* ATA + 0x52 */
234 	u16 reserved11;
235 	u16 fifo_lfrdp;		/* ATA + 0x56 */
236 	u16 reserved12;
237 	u16 fifo_lfwrp;		/* ATA + 0x5a */
238 
239 	/* Drive TaskFile registers */
240 	u8  tf_control;		/* ATA + 0x5c TASKFILE Control/Alt Status */
241 	u8  reserved13[3];
242 	u16 tf_data;		/* ATA + 0x60 TASKFILE Data */
243 	u16 reserved14;
244 	u8  tf_features;	/* ATA + 0x64 TASKFILE Features/Error */
245 	u8  reserved15[3];
246 	u8  tf_sec_count;	/* ATA + 0x68 TASKFILE Sector Count */
247 	u8  reserved16[3];
248 	u8  tf_sec_num;		/* ATA + 0x6c TASKFILE Sector Number */
249 	u8  reserved17[3];
250 	u8  tf_cyl_low;		/* ATA + 0x70 TASKFILE Cylinder Low */
251 	u8  reserved18[3];
252 	u8  tf_cyl_high;	/* ATA + 0x74 TASKFILE Cylinder High */
253 	u8  reserved19[3];
254 	u8  tf_dev_head;	/* ATA + 0x78 TASKFILE Device/Head */
255 	u8  reserved20[3];
256 	u8  tf_command;		/* ATA + 0x7c TASKFILE Command/Status */
257 	u8  dma_mode;		/* ATA + 0x7d ATA Host DMA Mode configuration */
258 	u8  reserved21[2];
259 };
260 
261 
262 /* ======================================================================== */
263 /* Aux fns                                                                  */
264 /* ======================================================================== */
265 
266 
267 /* MPC52xx low level hw control */
268 static int
269 mpc52xx_ata_compute_pio_timings(struct mpc52xx_ata_priv *priv, int dev, int pio)
270 {
271 	struct mpc52xx_ata_timings *timing = &priv->timings[dev];
272 	unsigned int ipb_period = priv->ipb_period;
273 	u32 t0, t1, t2_8, t2_16, t2i, t4, ta;
274 
275 	if ((pio < 0) || (pio > 4))
276 		return -EINVAL;
277 
278 	t0	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t0[pio]);
279 	t1	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t1[pio]);
280 	t2_8	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t2_8[pio]);
281 	t2_16	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t2_16[pio]);
282 	t2i	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t2i[pio]);
283 	t4	= CALC_CLKCYC(ipb_period, 1000 * ataspec_t4[pio]);
284 	ta	= CALC_CLKCYC(ipb_period, 1000 * ataspec_ta[pio]);
285 
286 	timing->pio1 = (t0 << 24) | (t2_8 << 16) | (t2_16 << 8) | (t2i);
287 	timing->pio2 = (t4 << 24) | (t1 << 16) | (ta << 8);
288 
289 	return 0;
290 }
291 
292 static int
293 mpc52xx_ata_compute_mdma_timings(struct mpc52xx_ata_priv *priv, int dev,
294 				 int speed)
295 {
296 	struct mpc52xx_ata_timings *t = &priv->timings[dev];
297 	const struct mdmaspec *s = &priv->mdmaspec[speed];
298 
299 	if (speed < 0 || speed > 2)
300 		return -EINVAL;
301 
302 	t->mdma1 = ((u32)s->t0M << 24) | ((u32)s->td << 16) | ((u32)s->tkw << 8) | s->tm;
303 	t->mdma2 = ((u32)s->th << 24) | ((u32)s->tj << 16) | ((u32)s->tn << 8);
304 	t->using_udma = 0;
305 
306 	return 0;
307 }
308 
309 static int
310 mpc52xx_ata_compute_udma_timings(struct mpc52xx_ata_priv *priv, int dev,
311 				 int speed)
312 {
313 	struct mpc52xx_ata_timings *t = &priv->timings[dev];
314 	const struct udmaspec *s = &priv->udmaspec[speed];
315 
316 	if (speed < 0 || speed > 2)
317 		return -EINVAL;
318 
319 	t->udma1 = ((u32)s->t2cyc << 24) | ((u32)s->tcyc << 16) | ((u32)s->tds << 8) | s->tdh;
320 	t->udma2 = ((u32)s->tdvs << 24) | ((u32)s->tdvh << 16) | ((u32)s->tfs << 8) | s->tli;
321 	t->udma3 = ((u32)s->tmli << 24) | ((u32)s->taz << 16) | ((u32)s->tenv << 8) | s->tsr;
322 	t->udma4 = ((u32)s->tss << 24) | ((u32)s->trfs << 16) | ((u32)s->trp << 8) | s->tack;
323 	t->udma5 = (u32)s->tzah << 24;
324 	t->using_udma = 1;
325 
326 	return 0;
327 }
328 
329 static void
330 mpc52xx_ata_apply_timings(struct mpc52xx_ata_priv *priv, int device)
331 {
332 	struct mpc52xx_ata __iomem *regs = priv->ata_regs;
333 	struct mpc52xx_ata_timings *timing = &priv->timings[device];
334 
335 	out_be32(&regs->pio1,  timing->pio1);
336 	out_be32(&regs->pio2,  timing->pio2);
337 	out_be32(&regs->mdma1, timing->mdma1);
338 	out_be32(&regs->mdma2, timing->mdma2);
339 	out_be32(&regs->udma1, timing->udma1);
340 	out_be32(&regs->udma2, timing->udma2);
341 	out_be32(&regs->udma3, timing->udma3);
342 	out_be32(&regs->udma4, timing->udma4);
343 	out_be32(&regs->udma5, timing->udma5);
344 	priv->csel = device;
345 }
346 
347 static int
348 mpc52xx_ata_hw_init(struct mpc52xx_ata_priv *priv)
349 {
350 	struct mpc52xx_ata __iomem *regs = priv->ata_regs;
351 	int tslot;
352 
353 	/* Clear share_cnt (all sample code do this ...) */
354 	out_be32(&regs->share_cnt, 0);
355 
356 	/* Configure and reset host */
357 	out_be32(&regs->config,
358 			MPC52xx_ATA_HOSTCONF_IE |
359 			MPC52xx_ATA_HOSTCONF_IORDY |
360 			MPC52xx_ATA_HOSTCONF_SMR |
361 			MPC52xx_ATA_HOSTCONF_FR);
362 
363 	udelay(10);
364 
365 	out_be32(&regs->config,
366 			MPC52xx_ATA_HOSTCONF_IE |
367 			MPC52xx_ATA_HOSTCONF_IORDY);
368 
369 	/* Set the time slot to 1us */
370 	tslot = CALC_CLKCYC(priv->ipb_period, 1000000);
371 	out_be32(&regs->share_cnt, tslot << 16);
372 
373 	/* Init timings to PIO0 */
374 	memset(priv->timings, 0x00, 2*sizeof(struct mpc52xx_ata_timings));
375 
376 	mpc52xx_ata_compute_pio_timings(priv, 0, 0);
377 	mpc52xx_ata_compute_pio_timings(priv, 1, 0);
378 
379 	mpc52xx_ata_apply_timings(priv, 0);
380 
381 	return 0;
382 }
383 
384 
385 /* ======================================================================== */
386 /* libata driver                                                            */
387 /* ======================================================================== */
388 
389 static void
390 mpc52xx_ata_set_piomode(struct ata_port *ap, struct ata_device *adev)
391 {
392 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
393 	int pio, rv;
394 
395 	pio = adev->pio_mode - XFER_PIO_0;
396 
397 	rv = mpc52xx_ata_compute_pio_timings(priv, adev->devno, pio);
398 
399 	if (rv) {
400 		dev_err(ap->dev, "error: invalid PIO mode: %d\n", pio);
401 		return;
402 	}
403 
404 	mpc52xx_ata_apply_timings(priv, adev->devno);
405 }
406 
407 static void
408 mpc52xx_ata_set_dmamode(struct ata_port *ap, struct ata_device *adev)
409 {
410 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
411 	int rv;
412 
413 	if (adev->dma_mode >= XFER_UDMA_0) {
414 		int dma = adev->dma_mode - XFER_UDMA_0;
415 		rv = mpc52xx_ata_compute_udma_timings(priv, adev->devno, dma);
416 	} else {
417 		int dma = adev->dma_mode - XFER_MW_DMA_0;
418 		rv = mpc52xx_ata_compute_mdma_timings(priv, adev->devno, dma);
419 	}
420 
421 	if (rv) {
422 		dev_alert(ap->dev,
423 			"Trying to select invalid DMA mode %d\n",
424 			adev->dma_mode);
425 		return;
426 	}
427 
428 	mpc52xx_ata_apply_timings(priv, adev->devno);
429 }
430 
431 static void
432 mpc52xx_ata_dev_select(struct ata_port *ap, unsigned int device)
433 {
434 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
435 
436 	if (device != priv->csel)
437 		mpc52xx_ata_apply_timings(priv, device);
438 
439 	ata_sff_dev_select(ap, device);
440 }
441 
442 static int
443 mpc52xx_ata_build_dmatable(struct ata_queued_cmd *qc)
444 {
445 	struct ata_port *ap = qc->ap;
446 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
447 	struct bcom_ata_bd *bd;
448 	unsigned int read = !(qc->tf.flags & ATA_TFLAG_WRITE), si;
449 	struct scatterlist *sg;
450 	int count = 0;
451 
452 	if (read)
453 		bcom_ata_rx_prepare(priv->dmatsk);
454 	else
455 		bcom_ata_tx_prepare(priv->dmatsk);
456 
457 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
458 		dma_addr_t cur_addr = sg_dma_address(sg);
459 		u32 cur_len = sg_dma_len(sg);
460 
461 		while (cur_len) {
462 			unsigned int tc = min(cur_len, MAX_DMA_BUFFER_SIZE);
463 			bd = (struct bcom_ata_bd *)
464 				bcom_prepare_next_buffer(priv->dmatsk);
465 
466 			if (read) {
467 				bd->status = tc;
468 				bd->src_pa = (__force u32) priv->ata_regs_pa +
469 					offsetof(struct mpc52xx_ata, fifo_data);
470 				bd->dst_pa = (__force u32) cur_addr;
471 			} else {
472 				bd->status = tc;
473 				bd->src_pa = (__force u32) cur_addr;
474 				bd->dst_pa = (__force u32) priv->ata_regs_pa +
475 					offsetof(struct mpc52xx_ata, fifo_data);
476 			}
477 
478 			bcom_submit_next_buffer(priv->dmatsk, NULL);
479 
480 			cur_addr += tc;
481 			cur_len -= tc;
482 			count++;
483 
484 			if (count > MAX_DMA_BUFFERS) {
485 				dev_alert(ap->dev, "dma table"
486 					"too small\n");
487 				goto use_pio_instead;
488 			}
489 		}
490 	}
491 	return 1;
492 
493  use_pio_instead:
494 	bcom_ata_reset_bd(priv->dmatsk);
495 	return 0;
496 }
497 
498 static void
499 mpc52xx_bmdma_setup(struct ata_queued_cmd *qc)
500 {
501 	struct ata_port *ap = qc->ap;
502 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
503 	struct mpc52xx_ata __iomem *regs = priv->ata_regs;
504 
505 	unsigned int read = !(qc->tf.flags & ATA_TFLAG_WRITE);
506 	u8 dma_mode;
507 
508 	if (!mpc52xx_ata_build_dmatable(qc))
509 		dev_alert(ap->dev, "%s: %i, return 1?\n",
510 			__func__, __LINE__);
511 
512 	/* Check FIFO is OK... */
513 	if (in_8(&priv->ata_regs->fifo_status) & MPC52xx_ATA_FIFOSTAT_ERROR)
514 		dev_alert(ap->dev, "%s: FIFO error detected: 0x%02x!\n",
515 			__func__, in_8(&priv->ata_regs->fifo_status));
516 
517 	if (read) {
518 		dma_mode = MPC52xx_ATA_DMAMODE_IE | MPC52xx_ATA_DMAMODE_READ |
519 				MPC52xx_ATA_DMAMODE_FE;
520 
521 		/* Setup FIFO if direction changed */
522 		if (priv->mpc52xx_ata_dma_last_write != 0) {
523 			priv->mpc52xx_ata_dma_last_write = 0;
524 
525 			/* Configure FIFO with granularity to 7 */
526 			out_8(&regs->fifo_control, 7);
527 			out_be16(&regs->fifo_alarm, 128);
528 
529 			/* Set FIFO Reset bit (FR) */
530 			out_8(&regs->dma_mode, MPC52xx_ATA_DMAMODE_FR);
531 		}
532 	} else {
533 		dma_mode = MPC52xx_ATA_DMAMODE_IE | MPC52xx_ATA_DMAMODE_WRITE;
534 
535 		/* Setup FIFO if direction changed */
536 		if (priv->mpc52xx_ata_dma_last_write != 1) {
537 			priv->mpc52xx_ata_dma_last_write = 1;
538 
539 			/* Configure FIFO with granularity to 4 */
540 			out_8(&regs->fifo_control, 4);
541 			out_be16(&regs->fifo_alarm, 128);
542 		}
543 	}
544 
545 	if (priv->timings[qc->dev->devno].using_udma)
546 		dma_mode |= MPC52xx_ATA_DMAMODE_UDMA;
547 
548 	out_8(&regs->dma_mode, dma_mode);
549 	priv->waiting_for_dma = ATA_DMA_ACTIVE;
550 
551 	ata_wait_idle(ap);
552 	ap->ops->sff_exec_command(ap, &qc->tf);
553 }
554 
555 static void
556 mpc52xx_bmdma_start(struct ata_queued_cmd *qc)
557 {
558 	struct ata_port *ap = qc->ap;
559 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
560 
561 	bcom_set_task_auto_start(priv->dmatsk->tasknum, priv->dmatsk->tasknum);
562 	bcom_enable(priv->dmatsk);
563 }
564 
565 static void
566 mpc52xx_bmdma_stop(struct ata_queued_cmd *qc)
567 {
568 	struct ata_port *ap = qc->ap;
569 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
570 
571 	bcom_disable(priv->dmatsk);
572 	bcom_ata_reset_bd(priv->dmatsk);
573 	priv->waiting_for_dma = 0;
574 
575 	/* Check FIFO is OK... */
576 	if (in_8(&priv->ata_regs->fifo_status) & MPC52xx_ATA_FIFOSTAT_ERROR)
577 		dev_alert(ap->dev, "%s: FIFO error detected: 0x%02x!\n",
578 			__func__, in_8(&priv->ata_regs->fifo_status));
579 }
580 
581 static u8
582 mpc52xx_bmdma_status(struct ata_port *ap)
583 {
584 	struct mpc52xx_ata_priv *priv = ap->host->private_data;
585 
586 	/* Check FIFO is OK... */
587 	if (in_8(&priv->ata_regs->fifo_status) & MPC52xx_ATA_FIFOSTAT_ERROR) {
588 		dev_alert(ap->dev, "%s: FIFO error detected: 0x%02x!\n",
589 			__func__, in_8(&priv->ata_regs->fifo_status));
590 		return priv->waiting_for_dma | ATA_DMA_ERR;
591 	}
592 
593 	return priv->waiting_for_dma;
594 }
595 
596 static irqreturn_t
597 mpc52xx_ata_task_irq(int irq, void *vpriv)
598 {
599 	struct mpc52xx_ata_priv *priv = vpriv;
600 	while (bcom_buffer_done(priv->dmatsk))
601 		bcom_retrieve_buffer(priv->dmatsk, NULL, NULL);
602 
603 	priv->waiting_for_dma |= ATA_DMA_INTR;
604 
605 	return IRQ_HANDLED;
606 }
607 
608 static struct scsi_host_template mpc52xx_ata_sht = {
609 	ATA_PIO_SHT(DRV_NAME),
610 };
611 
612 static struct ata_port_operations mpc52xx_ata_port_ops = {
613 	.inherits		= &ata_bmdma_port_ops,
614 	.sff_dev_select		= mpc52xx_ata_dev_select,
615 	.set_piomode		= mpc52xx_ata_set_piomode,
616 	.set_dmamode		= mpc52xx_ata_set_dmamode,
617 	.bmdma_setup		= mpc52xx_bmdma_setup,
618 	.bmdma_start		= mpc52xx_bmdma_start,
619 	.bmdma_stop		= mpc52xx_bmdma_stop,
620 	.bmdma_status		= mpc52xx_bmdma_status,
621 	.qc_prep		= ata_noop_qc_prep,
622 };
623 
624 static int mpc52xx_ata_init_one(struct device *dev,
625 				struct mpc52xx_ata_priv *priv,
626 				unsigned long raw_ata_regs,
627 				int mwdma_mask, int udma_mask)
628 {
629 	struct ata_host *host;
630 	struct ata_port *ap;
631 	struct ata_ioports *aio;
632 
633 	host = ata_host_alloc(dev, 1);
634 	if (!host)
635 		return -ENOMEM;
636 
637 	ap = host->ports[0];
638 	ap->flags		|= ATA_FLAG_SLAVE_POSS;
639 	ap->pio_mask		= ATA_PIO4;
640 	ap->mwdma_mask		= mwdma_mask;
641 	ap->udma_mask		= udma_mask;
642 	ap->ops			= &mpc52xx_ata_port_ops;
643 	host->private_data	= priv;
644 
645 	aio = &ap->ioaddr;
646 	aio->cmd_addr		= NULL;	/* Don't have a classic reg block */
647 	aio->altstatus_addr	= &priv->ata_regs->tf_control;
648 	aio->ctl_addr		= &priv->ata_regs->tf_control;
649 	aio->data_addr		= &priv->ata_regs->tf_data;
650 	aio->error_addr		= &priv->ata_regs->tf_features;
651 	aio->feature_addr	= &priv->ata_regs->tf_features;
652 	aio->nsect_addr		= &priv->ata_regs->tf_sec_count;
653 	aio->lbal_addr		= &priv->ata_regs->tf_sec_num;
654 	aio->lbam_addr		= &priv->ata_regs->tf_cyl_low;
655 	aio->lbah_addr		= &priv->ata_regs->tf_cyl_high;
656 	aio->device_addr	= &priv->ata_regs->tf_dev_head;
657 	aio->status_addr	= &priv->ata_regs->tf_command;
658 	aio->command_addr	= &priv->ata_regs->tf_command;
659 
660 	ata_port_desc(ap, "ata_regs 0x%lx", raw_ata_regs);
661 
662 	/* activate host */
663 	return ata_host_activate(host, priv->ata_irq, ata_bmdma_interrupt, 0,
664 				 &mpc52xx_ata_sht);
665 }
666 
667 /* ======================================================================== */
668 /* OF Platform driver                                                       */
669 /* ======================================================================== */
670 
671 static int mpc52xx_ata_probe(struct platform_device *op)
672 {
673 	unsigned int ipb_freq;
674 	struct resource res_mem;
675 	int ata_irq = 0;
676 	struct mpc52xx_ata __iomem *ata_regs;
677 	struct mpc52xx_ata_priv *priv = NULL;
678 	int rv, task_irq;
679 	int mwdma_mask = 0, udma_mask = 0;
680 	const __be32 *prop;
681 	int proplen;
682 	struct bcom_task *dmatsk;
683 
684 	/* Get ipb frequency */
685 	ipb_freq = mpc5xxx_get_bus_frequency(op->dev.of_node);
686 	if (!ipb_freq) {
687 		dev_err(&op->dev, "could not determine IPB bus frequency\n");
688 		return -ENODEV;
689 	}
690 
691 	/* Get device base address from device tree, request the region
692 	 * and ioremap it. */
693 	rv = of_address_to_resource(op->dev.of_node, 0, &res_mem);
694 	if (rv) {
695 		dev_err(&op->dev, "could not determine device base address\n");
696 		return rv;
697 	}
698 
699 	if (!devm_request_mem_region(&op->dev, res_mem.start,
700 				     sizeof(*ata_regs), DRV_NAME)) {
701 		dev_err(&op->dev, "error requesting register region\n");
702 		return -EBUSY;
703 	}
704 
705 	ata_regs = devm_ioremap(&op->dev, res_mem.start, sizeof(*ata_regs));
706 	if (!ata_regs) {
707 		dev_err(&op->dev, "error mapping device registers\n");
708 		return -ENOMEM;
709 	}
710 
711 	/*
712 	 * By default, all DMA modes are disabled for the MPC5200.  Some
713 	 * boards don't have the required signals routed to make DMA work.
714 	 * Also, the MPC5200B has a silicon bug that causes data corruption
715 	 * with UDMA if it is used at the same time as the LocalPlus bus.
716 	 *
717 	 * Instead of trying to guess what modes are usable, check the
718 	 * ATA device tree node to find out what DMA modes work on the board.
719 	 * UDMA/MWDMA modes can also be forced by adding "libata.force=<mode>"
720 	 * to the kernel boot parameters.
721 	 *
722 	 * The MPC5200 ATA controller supports MWDMA modes 0, 1 and 2 and
723 	 * UDMA modes 0, 1 and 2.
724 	 */
725 	prop = of_get_property(op->dev.of_node, "mwdma-mode", &proplen);
726 	if ((prop) && (proplen >= 4))
727 		mwdma_mask = ATA_MWDMA2 & ((1 << (*prop + 1)) - 1);
728 	prop = of_get_property(op->dev.of_node, "udma-mode", &proplen);
729 	if ((prop) && (proplen >= 4))
730 		udma_mask = ATA_UDMA2 & ((1 << (*prop + 1)) - 1);
731 
732 	ata_irq = irq_of_parse_and_map(op->dev.of_node, 0);
733 	if (ata_irq == NO_IRQ) {
734 		dev_err(&op->dev, "error mapping irq\n");
735 		return -EINVAL;
736 	}
737 
738 	/* Prepare our private structure */
739 	priv = devm_kzalloc(&op->dev, sizeof(*priv), GFP_ATOMIC);
740 	if (!priv) {
741 		dev_err(&op->dev, "error allocating private structure\n");
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 	return ata_host_suspend(host, state);
829 }
830 
831 static int
832 mpc52xx_ata_resume(struct platform_device *op)
833 {
834 	struct ata_host *host = platform_get_drvdata(op);
835 	struct mpc52xx_ata_priv *priv = host->private_data;
836 	int rv;
837 
838 	rv = mpc52xx_ata_hw_init(priv);
839 	if (rv) {
840 		dev_err(host->dev, "error initializing hardware\n");
841 		return rv;
842 	}
843 
844 	ata_host_resume(host);
845 
846 	return 0;
847 }
848 #endif
849 
850 static struct of_device_id mpc52xx_ata_of_match[] = {
851 	{ .compatible = "fsl,mpc5200-ata", },
852 	{ .compatible = "mpc5200-ata", },
853 	{},
854 };
855 
856 
857 static struct platform_driver mpc52xx_ata_of_platform_driver = {
858 	.probe		= mpc52xx_ata_probe,
859 	.remove		= mpc52xx_ata_remove,
860 #ifdef CONFIG_PM_SLEEP
861 	.suspend	= mpc52xx_ata_suspend,
862 	.resume		= mpc52xx_ata_resume,
863 #endif
864 	.driver		= {
865 		.name	= DRV_NAME,
866 		.owner	= THIS_MODULE,
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