xref: /openbmc/u-boot/drivers/spi/ich.c (revision 3c03f492)
1 /*
2  * Copyright (c) 2011-12 The Chromium OS Authors.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  *
6  * This file is derived from the flashrom project.
7  */
8 
9 #include <common.h>
10 #include <dm.h>
11 #include <errno.h>
12 #include <malloc.h>
13 #include <pch.h>
14 #include <pci.h>
15 #include <pci_ids.h>
16 #include <spi.h>
17 #include <asm/io.h>
18 
19 #include "ich.h"
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 #ifdef DEBUG_TRACE
24 #define debug_trace(fmt, args...) debug(fmt, ##args)
25 #else
26 #define debug_trace(x, args...)
27 #endif
28 
29 static u8 ich_readb(struct ich_spi_priv *priv, int reg)
30 {
31 	u8 value = readb(priv->base + reg);
32 
33 	debug_trace("read %2.2x from %4.4x\n", value, reg);
34 
35 	return value;
36 }
37 
38 static u16 ich_readw(struct ich_spi_priv *priv, int reg)
39 {
40 	u16 value = readw(priv->base + reg);
41 
42 	debug_trace("read %4.4x from %4.4x\n", value, reg);
43 
44 	return value;
45 }
46 
47 static u32 ich_readl(struct ich_spi_priv *priv, int reg)
48 {
49 	u32 value = readl(priv->base + reg);
50 
51 	debug_trace("read %8.8x from %4.4x\n", value, reg);
52 
53 	return value;
54 }
55 
56 static void ich_writeb(struct ich_spi_priv *priv, u8 value, int reg)
57 {
58 	writeb(value, priv->base + reg);
59 	debug_trace("wrote %2.2x to %4.4x\n", value, reg);
60 }
61 
62 static void ich_writew(struct ich_spi_priv *priv, u16 value, int reg)
63 {
64 	writew(value, priv->base + reg);
65 	debug_trace("wrote %4.4x to %4.4x\n", value, reg);
66 }
67 
68 static void ich_writel(struct ich_spi_priv *priv, u32 value, int reg)
69 {
70 	writel(value, priv->base + reg);
71 	debug_trace("wrote %8.8x to %4.4x\n", value, reg);
72 }
73 
74 static void write_reg(struct ich_spi_priv *priv, const void *value,
75 		      int dest_reg, uint32_t size)
76 {
77 	memcpy_toio(priv->base + dest_reg, value, size);
78 }
79 
80 static void read_reg(struct ich_spi_priv *priv, int src_reg, void *value,
81 		     uint32_t size)
82 {
83 	memcpy_fromio(value, priv->base + src_reg, size);
84 }
85 
86 static void ich_set_bbar(struct ich_spi_priv *ctlr, uint32_t minaddr)
87 {
88 	const uint32_t bbar_mask = 0x00ffff00;
89 	uint32_t ichspi_bbar;
90 
91 	minaddr &= bbar_mask;
92 	ichspi_bbar = ich_readl(ctlr, ctlr->bbar) & ~bbar_mask;
93 	ichspi_bbar |= minaddr;
94 	ich_writel(ctlr, ichspi_bbar, ctlr->bbar);
95 }
96 
97 /* @return 1 if the SPI flash supports the 33MHz speed */
98 static int ich9_can_do_33mhz(struct udevice *dev)
99 {
100 	u32 fdod, speed;
101 
102 	/* Observe SPI Descriptor Component Section 0 */
103 	dm_pci_write_config32(dev->parent, 0xb0, 0x1000);
104 
105 	/* Extract the Write/Erase SPI Frequency from descriptor */
106 	dm_pci_read_config32(dev->parent, 0xb4, &fdod);
107 
108 	/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
109 	speed = (fdod >> 21) & 7;
110 
111 	return speed == 1;
112 }
113 
114 static int ich_init_controller(struct udevice *dev,
115 			       struct ich_spi_platdata *plat,
116 			       struct ich_spi_priv *ctlr)
117 {
118 	ulong sbase_addr;
119 	void *sbase;
120 
121 	/* SBASE is similar */
122 	pch_get_spi_base(dev->parent, &sbase_addr);
123 	sbase = (void *)sbase_addr;
124 	debug("%s: sbase=%p\n", __func__, sbase);
125 
126 	if (plat->ich_version == ICHV_7) {
127 		struct ich7_spi_regs *ich7_spi = sbase;
128 
129 		ich7_spi = (struct ich7_spi_regs *)sbase;
130 		ctlr->ichspi_lock = readw(&ich7_spi->spis) & SPIS_LOCK;
131 		ctlr->opmenu = offsetof(struct ich7_spi_regs, opmenu);
132 		ctlr->menubytes = sizeof(ich7_spi->opmenu);
133 		ctlr->optype = offsetof(struct ich7_spi_regs, optype);
134 		ctlr->addr = offsetof(struct ich7_spi_regs, spia);
135 		ctlr->data = offsetof(struct ich7_spi_regs, spid);
136 		ctlr->databytes = sizeof(ich7_spi->spid);
137 		ctlr->status = offsetof(struct ich7_spi_regs, spis);
138 		ctlr->control = offsetof(struct ich7_spi_regs, spic);
139 		ctlr->bbar = offsetof(struct ich7_spi_regs, bbar);
140 		ctlr->preop = offsetof(struct ich7_spi_regs, preop);
141 		ctlr->base = ich7_spi;
142 	} else if (plat->ich_version == ICHV_9) {
143 		struct ich9_spi_regs *ich9_spi = sbase;
144 
145 		ctlr->ichspi_lock = readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
146 		ctlr->opmenu = offsetof(struct ich9_spi_regs, opmenu);
147 		ctlr->menubytes = sizeof(ich9_spi->opmenu);
148 		ctlr->optype = offsetof(struct ich9_spi_regs, optype);
149 		ctlr->addr = offsetof(struct ich9_spi_regs, faddr);
150 		ctlr->data = offsetof(struct ich9_spi_regs, fdata);
151 		ctlr->databytes = sizeof(ich9_spi->fdata);
152 		ctlr->status = offsetof(struct ich9_spi_regs, ssfs);
153 		ctlr->control = offsetof(struct ich9_spi_regs, ssfc);
154 		ctlr->speed = ctlr->control + 2;
155 		ctlr->bbar = offsetof(struct ich9_spi_regs, bbar);
156 		ctlr->preop = offsetof(struct ich9_spi_regs, preop);
157 		ctlr->bcr = offsetof(struct ich9_spi_regs, bcr);
158 		ctlr->pr = &ich9_spi->pr[0];
159 		ctlr->base = ich9_spi;
160 	} else {
161 		debug("ICH SPI: Unrecognised ICH version %d\n",
162 		      plat->ich_version);
163 		return -EINVAL;
164 	}
165 
166 	/* Work out the maximum speed we can support */
167 	ctlr->max_speed = 20000000;
168 	if (plat->ich_version == ICHV_9 && ich9_can_do_33mhz(dev))
169 		ctlr->max_speed = 33000000;
170 	debug("ICH SPI: Version ID %d detected at %p, speed %ld\n",
171 	      plat->ich_version, ctlr->base, ctlr->max_speed);
172 
173 	ich_set_bbar(ctlr, 0);
174 
175 	return 0;
176 }
177 
178 static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
179 {
180 	trans->out += bytes;
181 	trans->bytesout -= bytes;
182 }
183 
184 static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
185 {
186 	trans->in += bytes;
187 	trans->bytesin -= bytes;
188 }
189 
190 static void spi_setup_type(struct spi_trans *trans, int data_bytes)
191 {
192 	trans->type = 0xFF;
193 
194 	/* Try to guess spi type from read/write sizes */
195 	if (trans->bytesin == 0) {
196 		if (trans->bytesout + data_bytes > 4)
197 			/*
198 			 * If bytesin = 0 and bytesout > 4, we presume this is
199 			 * a write data operation, which is accompanied by an
200 			 * address.
201 			 */
202 			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
203 		else
204 			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
205 		return;
206 	}
207 
208 	if (trans->bytesout == 1) {	/* and bytesin is > 0 */
209 		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
210 		return;
211 	}
212 
213 	if (trans->bytesout == 4)	/* and bytesin is > 0 */
214 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
215 
216 	/* Fast read command is called with 5 bytes instead of 4 */
217 	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
218 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
219 		--trans->bytesout;
220 	}
221 }
222 
223 static int spi_setup_opcode(struct ich_spi_priv *ctlr, struct spi_trans *trans)
224 {
225 	uint16_t optypes;
226 	uint8_t opmenu[ctlr->menubytes];
227 
228 	trans->opcode = trans->out[0];
229 	spi_use_out(trans, 1);
230 	if (!ctlr->ichspi_lock) {
231 		/* The lock is off, so just use index 0. */
232 		ich_writeb(ctlr, trans->opcode, ctlr->opmenu);
233 		optypes = ich_readw(ctlr, ctlr->optype);
234 		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
235 		ich_writew(ctlr, optypes, ctlr->optype);
236 		return 0;
237 	} else {
238 		/* The lock is on. See if what we need is on the menu. */
239 		uint8_t optype;
240 		uint16_t opcode_index;
241 
242 		/* Write Enable is handled as atomic prefix */
243 		if (trans->opcode == SPI_OPCODE_WREN)
244 			return 0;
245 
246 		read_reg(ctlr, ctlr->opmenu, opmenu, sizeof(opmenu));
247 		for (opcode_index = 0; opcode_index < ctlr->menubytes;
248 				opcode_index++) {
249 			if (opmenu[opcode_index] == trans->opcode)
250 				break;
251 		}
252 
253 		if (opcode_index == ctlr->menubytes) {
254 			printf("ICH SPI: Opcode %x not found\n",
255 			       trans->opcode);
256 			return -EINVAL;
257 		}
258 
259 		optypes = ich_readw(ctlr, ctlr->optype);
260 		optype = (optypes >> (opcode_index * 2)) & 0x3;
261 		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
262 		    optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
263 		    trans->bytesout >= 3) {
264 			/* We guessed wrong earlier. Fix it up. */
265 			trans->type = optype;
266 		}
267 		if (optype != trans->type) {
268 			printf("ICH SPI: Transaction doesn't fit type %d\n",
269 			       optype);
270 			return -ENOSPC;
271 		}
272 		return opcode_index;
273 	}
274 }
275 
276 static int spi_setup_offset(struct spi_trans *trans)
277 {
278 	/* Separate the SPI address and data */
279 	switch (trans->type) {
280 	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
281 	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
282 		return 0;
283 	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
284 	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
285 		trans->offset = ((uint32_t)trans->out[0] << 16) |
286 				((uint32_t)trans->out[1] << 8) |
287 				((uint32_t)trans->out[2] << 0);
288 		spi_use_out(trans, 3);
289 		return 1;
290 	default:
291 		printf("Unrecognized SPI transaction type %#x\n", trans->type);
292 		return -EPROTO;
293 	}
294 }
295 
296 /*
297  * Wait for up to 6s til status register bit(s) turn 1 (in case wait_til_set
298  * below is true) or 0. In case the wait was for the bit(s) to set - write
299  * those bits back, which would cause resetting them.
300  *
301  * Return the last read status value on success or -1 on failure.
302  */
303 static int ich_status_poll(struct ich_spi_priv *ctlr, u16 bitmask,
304 			   int wait_til_set)
305 {
306 	int timeout = 600000; /* This will result in 6s */
307 	u16 status = 0;
308 
309 	while (timeout--) {
310 		status = ich_readw(ctlr, ctlr->status);
311 		if (wait_til_set ^ ((status & bitmask) == 0)) {
312 			if (wait_til_set) {
313 				ich_writew(ctlr, status & bitmask,
314 					   ctlr->status);
315 			}
316 			return status;
317 		}
318 		udelay(10);
319 	}
320 
321 	printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
322 	       status, bitmask);
323 	return -ETIMEDOUT;
324 }
325 
326 static int ich_spi_xfer(struct udevice *dev, unsigned int bitlen,
327 			const void *dout, void *din, unsigned long flags)
328 {
329 	struct udevice *bus = dev_get_parent(dev);
330 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
331 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
332 	uint16_t control;
333 	int16_t opcode_index;
334 	int with_address;
335 	int status;
336 	int bytes = bitlen / 8;
337 	struct spi_trans *trans = &ctlr->trans;
338 	unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
339 	int using_cmd = 0;
340 	int ret;
341 
342 	/* We don't support writing partial bytes */
343 	if (bitlen % 8) {
344 		debug("ICH SPI: Accessing partial bytes not supported\n");
345 		return -EPROTONOSUPPORT;
346 	}
347 
348 	/* An empty end transaction can be ignored */
349 	if (type == SPI_XFER_END && !dout && !din)
350 		return 0;
351 
352 	if (type & SPI_XFER_BEGIN)
353 		memset(trans, '\0', sizeof(*trans));
354 
355 	/* Dp we need to come back later to finish it? */
356 	if (dout && type == SPI_XFER_BEGIN) {
357 		if (bytes > ICH_MAX_CMD_LEN) {
358 			debug("ICH SPI: Command length limit exceeded\n");
359 			return -ENOSPC;
360 		}
361 		memcpy(trans->cmd, dout, bytes);
362 		trans->cmd_len = bytes;
363 		debug_trace("ICH SPI: Saved %d bytes\n", bytes);
364 		return 0;
365 	}
366 
367 	/*
368 	 * We process a 'middle' spi_xfer() call, which has no
369 	 * SPI_XFER_BEGIN/END, as an independent transaction as if it had
370 	 * an end. We therefore repeat the command. This is because ICH
371 	 * seems to have no support for this, or because interest (in digging
372 	 * out the details and creating a special case in the code) is low.
373 	 */
374 	if (trans->cmd_len) {
375 		trans->out = trans->cmd;
376 		trans->bytesout = trans->cmd_len;
377 		using_cmd = 1;
378 		debug_trace("ICH SPI: Using %d bytes\n", trans->cmd_len);
379 	} else {
380 		trans->out = dout;
381 		trans->bytesout = dout ? bytes : 0;
382 	}
383 
384 	trans->in = din;
385 	trans->bytesin = din ? bytes : 0;
386 
387 	/* There has to always at least be an opcode */
388 	if (!trans->bytesout) {
389 		debug("ICH SPI: No opcode for transfer\n");
390 		return -EPROTO;
391 	}
392 
393 	ret = ich_status_poll(ctlr, SPIS_SCIP, 0);
394 	if (ret < 0)
395 		return ret;
396 
397 	if (plat->ich_version == ICHV_7)
398 		ich_writew(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
399 	else
400 		ich_writeb(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
401 
402 	spi_setup_type(trans, using_cmd ? bytes : 0);
403 	opcode_index = spi_setup_opcode(ctlr, trans);
404 	if (opcode_index < 0)
405 		return -EINVAL;
406 	with_address = spi_setup_offset(trans);
407 	if (with_address < 0)
408 		return -EINVAL;
409 
410 	if (trans->opcode == SPI_OPCODE_WREN) {
411 		/*
412 		 * Treat Write Enable as Atomic Pre-Op if possible
413 		 * in order to prevent the Management Engine from
414 		 * issuing a transaction between WREN and DATA.
415 		 */
416 		if (!ctlr->ichspi_lock)
417 			ich_writew(ctlr, trans->opcode, ctlr->preop);
418 		return 0;
419 	}
420 
421 	if (ctlr->speed && ctlr->max_speed >= 33000000) {
422 		int byte;
423 
424 		byte = ich_readb(ctlr, ctlr->speed);
425 		if (ctlr->cur_speed >= 33000000)
426 			byte |= SSFC_SCF_33MHZ;
427 		else
428 			byte &= ~SSFC_SCF_33MHZ;
429 		ich_writeb(ctlr, byte, ctlr->speed);
430 	}
431 
432 	/* See if we have used up the command data */
433 	if (using_cmd && dout && bytes) {
434 		trans->out = dout;
435 		trans->bytesout = bytes;
436 		debug_trace("ICH SPI: Moving to data, %d bytes\n", bytes);
437 	}
438 
439 	/* Preset control fields */
440 	control = ich_readw(ctlr, ctlr->control);
441 	control &= ~SSFC_RESERVED;
442 	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
443 
444 	/* Issue atomic preop cycle if needed */
445 	if (ich_readw(ctlr, ctlr->preop))
446 		control |= SPIC_ACS;
447 
448 	if (!trans->bytesout && !trans->bytesin) {
449 		/* SPI addresses are 24 bit only */
450 		if (with_address) {
451 			ich_writel(ctlr, trans->offset & 0x00FFFFFF,
452 				   ctlr->addr);
453 		}
454 		/*
455 		 * This is a 'no data' command (like Write Enable), its
456 		 * bitesout size was 1, decremented to zero while executing
457 		 * spi_setup_opcode() above. Tell the chip to send the
458 		 * command.
459 		 */
460 		ich_writew(ctlr, control, ctlr->control);
461 
462 		/* wait for the result */
463 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
464 		if (status < 0)
465 			return status;
466 
467 		if (status & SPIS_FCERR) {
468 			debug("ICH SPI: Command transaction error\n");
469 			return -EIO;
470 		}
471 
472 		return 0;
473 	}
474 
475 	/*
476 	 * Check if this is a write command atempting to transfer more bytes
477 	 * than the controller can handle. Iterations for writes are not
478 	 * supported here because each SPI write command needs to be preceded
479 	 * and followed by other SPI commands, and this sequence is controlled
480 	 * by the SPI chip driver.
481 	 */
482 	if (trans->bytesout > ctlr->databytes) {
483 		debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
484 		return -EPROTO;
485 	}
486 
487 	/*
488 	 * Read or write up to databytes bytes at a time until everything has
489 	 * been sent.
490 	 */
491 	while (trans->bytesout || trans->bytesin) {
492 		uint32_t data_length;
493 
494 		/* SPI addresses are 24 bit only */
495 		ich_writel(ctlr, trans->offset & 0x00FFFFFF, ctlr->addr);
496 
497 		if (trans->bytesout)
498 			data_length = min(trans->bytesout, ctlr->databytes);
499 		else
500 			data_length = min(trans->bytesin, ctlr->databytes);
501 
502 		/* Program data into FDATA0 to N */
503 		if (trans->bytesout) {
504 			write_reg(ctlr, trans->out, ctlr->data, data_length);
505 			spi_use_out(trans, data_length);
506 			if (with_address)
507 				trans->offset += data_length;
508 		}
509 
510 		/* Add proper control fields' values */
511 		control &= ~((ctlr->databytes - 1) << 8);
512 		control |= SPIC_DS;
513 		control |= (data_length - 1) << 8;
514 
515 		/* write it */
516 		ich_writew(ctlr, control, ctlr->control);
517 
518 		/* Wait for Cycle Done Status or Flash Cycle Error */
519 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
520 		if (status < 0)
521 			return status;
522 
523 		if (status & SPIS_FCERR) {
524 			debug("ICH SPI: Data transaction error %x\n", status);
525 			return -EIO;
526 		}
527 
528 		if (trans->bytesin) {
529 			read_reg(ctlr, ctlr->data, trans->in, data_length);
530 			spi_use_in(trans, data_length);
531 			if (with_address)
532 				trans->offset += data_length;
533 		}
534 	}
535 
536 	/* Clear atomic preop now that xfer is done */
537 	ich_writew(ctlr, 0, ctlr->preop);
538 
539 	return 0;
540 }
541 
542 /*
543  * This uses the SPI controller from the Intel Cougar Point and Panther Point
544  * PCH to write-protect portions of the SPI flash until reboot. The changes
545  * don't actually take effect until the HSFS[FLOCKDN] bit is set, but that's
546  * done elsewhere.
547  */
548 int spi_write_protect_region(struct udevice *dev, uint32_t lower_limit,
549 			     uint32_t length, int hint)
550 {
551 	struct udevice *bus = dev->parent;
552 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
553 	uint32_t tmplong;
554 	uint32_t upper_limit;
555 
556 	if (!ctlr->pr) {
557 		printf("%s: operation not supported on this chipset\n",
558 		       __func__);
559 		return -ENOSYS;
560 	}
561 
562 	if (length == 0 ||
563 	    lower_limit > (0xFFFFFFFFUL - length) + 1 ||
564 	    hint < 0 || hint > 4) {
565 		printf("%s(0x%x, 0x%x, %d): invalid args\n", __func__,
566 		       lower_limit, length, hint);
567 		return -EPERM;
568 	}
569 
570 	upper_limit = lower_limit + length - 1;
571 
572 	/*
573 	 * Determine bits to write, as follows:
574 	 *  31     Write-protection enable (includes erase operation)
575 	 *  30:29  reserved
576 	 *  28:16  Upper Limit (FLA address bits 24:12, with 11:0 == 0xfff)
577 	 *  15     Read-protection enable
578 	 *  14:13  reserved
579 	 *  12:0   Lower Limit (FLA address bits 24:12, with 11:0 == 0x000)
580 	 */
581 	tmplong = 0x80000000 |
582 		((upper_limit & 0x01fff000) << 4) |
583 		((lower_limit & 0x01fff000) >> 12);
584 
585 	printf("%s: writing 0x%08x to %p\n", __func__, tmplong,
586 	       &ctlr->pr[hint]);
587 	ctlr->pr[hint] = tmplong;
588 
589 	return 0;
590 }
591 
592 static int ich_spi_probe(struct udevice *dev)
593 {
594 	struct ich_spi_platdata *plat = dev_get_platdata(dev);
595 	struct ich_spi_priv *priv = dev_get_priv(dev);
596 	uint8_t bios_cntl;
597 	int ret;
598 
599 	ret = ich_init_controller(dev, plat, priv);
600 	if (ret)
601 		return ret;
602 	/* Disable the BIOS write protect so write commands are allowed */
603 	ret = pch_set_spi_protect(dev->parent, false);
604 	if (ret == -ENOSYS) {
605 		bios_cntl = ich_readb(priv, priv->bcr);
606 		bios_cntl &= ~BIT(5);	/* clear Enable InSMM_STS (EISS) */
607 		bios_cntl |= 1;		/* Write Protect Disable (WPD) */
608 		ich_writeb(priv, bios_cntl, priv->bcr);
609 	} else if (ret) {
610 		debug("%s: Failed to disable write-protect: err=%d\n",
611 		      __func__, ret);
612 		return ret;
613 	}
614 
615 	priv->cur_speed = priv->max_speed;
616 
617 	return 0;
618 }
619 
620 static int ich_spi_set_speed(struct udevice *bus, uint speed)
621 {
622 	struct ich_spi_priv *priv = dev_get_priv(bus);
623 
624 	priv->cur_speed = speed;
625 
626 	return 0;
627 }
628 
629 static int ich_spi_set_mode(struct udevice *bus, uint mode)
630 {
631 	debug("%s: mode=%d\n", __func__, mode);
632 
633 	return 0;
634 }
635 
636 static int ich_spi_child_pre_probe(struct udevice *dev)
637 {
638 	struct udevice *bus = dev_get_parent(dev);
639 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
640 	struct ich_spi_priv *priv = dev_get_priv(bus);
641 	struct spi_slave *slave = dev_get_parent_priv(dev);
642 
643 	/*
644 	 * Yes this controller can only write a small number of bytes at
645 	 * once! The limit is typically 64 bytes.
646 	 */
647 	slave->max_write_size = priv->databytes;
648 	/*
649 	 * ICH 7 SPI controller only supports array read command
650 	 * and byte program command for SST flash
651 	 */
652 	if (plat->ich_version == ICHV_7)
653 		slave->mode = SPI_RX_SLOW | SPI_TX_BYTE;
654 
655 	return 0;
656 }
657 
658 static int ich_spi_ofdata_to_platdata(struct udevice *dev)
659 {
660 	struct ich_spi_platdata *plat = dev_get_platdata(dev);
661 	int node = dev_of_offset(dev);
662 	int ret;
663 
664 	ret = fdt_node_check_compatible(gd->fdt_blob, node, "intel,ich7-spi");
665 	if (ret == 0) {
666 		plat->ich_version = ICHV_7;
667 	} else {
668 		ret = fdt_node_check_compatible(gd->fdt_blob, node,
669 						"intel,ich9-spi");
670 		if (ret == 0)
671 			plat->ich_version = ICHV_9;
672 	}
673 
674 	return ret;
675 }
676 
677 static const struct dm_spi_ops ich_spi_ops = {
678 	.xfer		= ich_spi_xfer,
679 	.set_speed	= ich_spi_set_speed,
680 	.set_mode	= ich_spi_set_mode,
681 	/*
682 	 * cs_info is not needed, since we require all chip selects to be
683 	 * in the device tree explicitly
684 	 */
685 };
686 
687 static const struct udevice_id ich_spi_ids[] = {
688 	{ .compatible = "intel,ich7-spi" },
689 	{ .compatible = "intel,ich9-spi" },
690 	{ }
691 };
692 
693 U_BOOT_DRIVER(ich_spi) = {
694 	.name	= "ich_spi",
695 	.id	= UCLASS_SPI,
696 	.of_match = ich_spi_ids,
697 	.ops	= &ich_spi_ops,
698 	.ofdata_to_platdata = ich_spi_ofdata_to_platdata,
699 	.platdata_auto_alloc_size = sizeof(struct ich_spi_platdata),
700 	.priv_auto_alloc_size = sizeof(struct ich_spi_priv),
701 	.child_pre_probe = ich_spi_child_pre_probe,
702 	.probe	= ich_spi_probe,
703 };
704