xref: /openbmc/u-boot/drivers/spi/ich.c (revision 9b5dbe13)
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 #include <common.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <malloc.h>
12 #include <pch.h>
13 #include <pci.h>
14 #include <pci_ids.h>
15 #include <spi.h>
16 #include <asm/io.h>
17 
18 #include "ich.h"
19 
20 #define SPI_OPCODE_WREN      0x06
21 #define SPI_OPCODE_FAST_READ 0x0b
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 struct ich_spi_platdata {
30 	enum pch_version ich_version;	/* Controller version, 7 or 9 */
31 };
32 
33 struct ich_spi_priv {
34 	int ichspi_lock;
35 	int locked;
36 	int opmenu;
37 	int menubytes;
38 	void *base;		/* Base of register set */
39 	int preop;
40 	int optype;
41 	int addr;
42 	int data;
43 	unsigned databytes;
44 	int status;
45 	int control;
46 	int bbar;
47 	int bcr;
48 	uint32_t *pr;		/* only for ich9 */
49 	int speed;		/* pointer to speed control */
50 	ulong max_speed;	/* Maximum bus speed in MHz */
51 	ulong cur_speed;	/* Current bus speed */
52 	struct spi_trans trans;	/* current transaction in progress */
53 };
54 
55 static u8 ich_readb(struct ich_spi_priv *priv, int reg)
56 {
57 	u8 value = readb(priv->base + reg);
58 
59 	debug_trace("read %2.2x from %4.4x\n", value, reg);
60 
61 	return value;
62 }
63 
64 static u16 ich_readw(struct ich_spi_priv *priv, int reg)
65 {
66 	u16 value = readw(priv->base + reg);
67 
68 	debug_trace("read %4.4x from %4.4x\n", value, reg);
69 
70 	return value;
71 }
72 
73 static u32 ich_readl(struct ich_spi_priv *priv, int reg)
74 {
75 	u32 value = readl(priv->base + reg);
76 
77 	debug_trace("read %8.8x from %4.4x\n", value, reg);
78 
79 	return value;
80 }
81 
82 static void ich_writeb(struct ich_spi_priv *priv, u8 value, int reg)
83 {
84 	writeb(value, priv->base + reg);
85 	debug_trace("wrote %2.2x to %4.4x\n", value, reg);
86 }
87 
88 static void ich_writew(struct ich_spi_priv *priv, u16 value, int reg)
89 {
90 	writew(value, priv->base + reg);
91 	debug_trace("wrote %4.4x to %4.4x\n", value, reg);
92 }
93 
94 static void ich_writel(struct ich_spi_priv *priv, u32 value, int reg)
95 {
96 	writel(value, priv->base + reg);
97 	debug_trace("wrote %8.8x to %4.4x\n", value, reg);
98 }
99 
100 static void write_reg(struct ich_spi_priv *priv, const void *value,
101 		      int dest_reg, uint32_t size)
102 {
103 	memcpy_toio(priv->base + dest_reg, value, size);
104 }
105 
106 static void read_reg(struct ich_spi_priv *priv, int src_reg, void *value,
107 		     uint32_t size)
108 {
109 	memcpy_fromio(value, priv->base + src_reg, size);
110 }
111 
112 static void ich_set_bbar(struct ich_spi_priv *ctlr, uint32_t minaddr)
113 {
114 	const uint32_t bbar_mask = 0x00ffff00;
115 	uint32_t ichspi_bbar;
116 
117 	minaddr &= bbar_mask;
118 	ichspi_bbar = ich_readl(ctlr, ctlr->bbar) & ~bbar_mask;
119 	ichspi_bbar |= minaddr;
120 	ich_writel(ctlr, ichspi_bbar, ctlr->bbar);
121 }
122 
123 /* @return 1 if the SPI flash supports the 33MHz speed */
124 static int ich9_can_do_33mhz(struct udevice *dev)
125 {
126 	u32 fdod, speed;
127 
128 	/* Observe SPI Descriptor Component Section 0 */
129 	dm_pci_write_config32(dev->parent, 0xb0, 0x1000);
130 
131 	/* Extract the Write/Erase SPI Frequency from descriptor */
132 	dm_pci_read_config32(dev->parent, 0xb4, &fdod);
133 
134 	/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
135 	speed = (fdod >> 21) & 7;
136 
137 	return speed == 1;
138 }
139 
140 static int ich_init_controller(struct udevice *dev,
141 			       struct ich_spi_platdata *plat,
142 			       struct ich_spi_priv *ctlr)
143 {
144 	ulong sbase_addr;
145 	void *sbase;
146 
147 	/* SBASE is similar */
148 	pch_get_sbase(dev->parent, &sbase_addr);
149 	sbase = (void *)sbase_addr;
150 	debug("%s: sbase=%p\n", __func__, sbase);
151 
152 	if (plat->ich_version == PCHV_7) {
153 		struct ich7_spi_regs *ich7_spi = sbase;
154 
155 		ich7_spi = (struct ich7_spi_regs *)sbase;
156 		ctlr->ichspi_lock = readw(&ich7_spi->spis) & SPIS_LOCK;
157 		ctlr->opmenu = offsetof(struct ich7_spi_regs, opmenu);
158 		ctlr->menubytes = sizeof(ich7_spi->opmenu);
159 		ctlr->optype = offsetof(struct ich7_spi_regs, optype);
160 		ctlr->addr = offsetof(struct ich7_spi_regs, spia);
161 		ctlr->data = offsetof(struct ich7_spi_regs, spid);
162 		ctlr->databytes = sizeof(ich7_spi->spid);
163 		ctlr->status = offsetof(struct ich7_spi_regs, spis);
164 		ctlr->control = offsetof(struct ich7_spi_regs, spic);
165 		ctlr->bbar = offsetof(struct ich7_spi_regs, bbar);
166 		ctlr->preop = offsetof(struct ich7_spi_regs, preop);
167 		ctlr->base = ich7_spi;
168 	} else if (plat->ich_version == PCHV_9) {
169 		struct ich9_spi_regs *ich9_spi = sbase;
170 
171 		ctlr->ichspi_lock = readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
172 		ctlr->opmenu = offsetof(struct ich9_spi_regs, opmenu);
173 		ctlr->menubytes = sizeof(ich9_spi->opmenu);
174 		ctlr->optype = offsetof(struct ich9_spi_regs, optype);
175 		ctlr->addr = offsetof(struct ich9_spi_regs, faddr);
176 		ctlr->data = offsetof(struct ich9_spi_regs, fdata);
177 		ctlr->databytes = sizeof(ich9_spi->fdata);
178 		ctlr->status = offsetof(struct ich9_spi_regs, ssfs);
179 		ctlr->control = offsetof(struct ich9_spi_regs, ssfc);
180 		ctlr->speed = ctlr->control + 2;
181 		ctlr->bbar = offsetof(struct ich9_spi_regs, bbar);
182 		ctlr->preop = offsetof(struct ich9_spi_regs, preop);
183 		ctlr->bcr = offsetof(struct ich9_spi_regs, bcr);
184 		ctlr->pr = &ich9_spi->pr[0];
185 		ctlr->base = ich9_spi;
186 	} else {
187 		debug("ICH SPI: Unrecognised ICH version %d\n",
188 		      plat->ich_version);
189 		return -EINVAL;
190 	}
191 
192 	/* Work out the maximum speed we can support */
193 	ctlr->max_speed = 20000000;
194 	if (plat->ich_version == PCHV_9 && ich9_can_do_33mhz(dev))
195 		ctlr->max_speed = 33000000;
196 	debug("ICH SPI: Version ID %d detected at %p, speed %ld\n",
197 	      plat->ich_version, ctlr->base, ctlr->max_speed);
198 
199 	ich_set_bbar(ctlr, 0);
200 
201 	return 0;
202 }
203 
204 static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
205 {
206 	trans->out += bytes;
207 	trans->bytesout -= bytes;
208 }
209 
210 static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
211 {
212 	trans->in += bytes;
213 	trans->bytesin -= bytes;
214 }
215 
216 static void spi_setup_type(struct spi_trans *trans, int data_bytes)
217 {
218 	trans->type = 0xFF;
219 
220 	/* Try to guess spi type from read/write sizes. */
221 	if (trans->bytesin == 0) {
222 		if (trans->bytesout + data_bytes > 4)
223 			/*
224 			 * If bytesin = 0 and bytesout > 4, we presume this is
225 			 * a write data operation, which is accompanied by an
226 			 * address.
227 			 */
228 			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
229 		else
230 			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
231 		return;
232 	}
233 
234 	if (trans->bytesout == 1) {	/* and bytesin is > 0 */
235 		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
236 		return;
237 	}
238 
239 	if (trans->bytesout == 4)	/* and bytesin is > 0 */
240 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
241 
242 	/* Fast read command is called with 5 bytes instead of 4 */
243 	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
244 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
245 		--trans->bytesout;
246 	}
247 }
248 
249 static int spi_setup_opcode(struct ich_spi_priv *ctlr, struct spi_trans *trans)
250 {
251 	uint16_t optypes;
252 	uint8_t opmenu[ctlr->menubytes];
253 
254 	trans->opcode = trans->out[0];
255 	spi_use_out(trans, 1);
256 	if (!ctlr->ichspi_lock) {
257 		/* The lock is off, so just use index 0. */
258 		ich_writeb(ctlr, trans->opcode, ctlr->opmenu);
259 		optypes = ich_readw(ctlr, ctlr->optype);
260 		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
261 		ich_writew(ctlr, optypes, ctlr->optype);
262 		return 0;
263 	} else {
264 		/* The lock is on. See if what we need is on the menu. */
265 		uint8_t optype;
266 		uint16_t opcode_index;
267 
268 		/* Write Enable is handled as atomic prefix */
269 		if (trans->opcode == SPI_OPCODE_WREN)
270 			return 0;
271 
272 		read_reg(ctlr, ctlr->opmenu, opmenu, sizeof(opmenu));
273 		for (opcode_index = 0; opcode_index < ctlr->menubytes;
274 				opcode_index++) {
275 			if (opmenu[opcode_index] == trans->opcode)
276 				break;
277 		}
278 
279 		if (opcode_index == ctlr->menubytes) {
280 			printf("ICH SPI: Opcode %x not found\n",
281 			       trans->opcode);
282 			return -EINVAL;
283 		}
284 
285 		optypes = ich_readw(ctlr, ctlr->optype);
286 		optype = (optypes >> (opcode_index * 2)) & 0x3;
287 		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
288 		    optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
289 		    trans->bytesout >= 3) {
290 			/* We guessed wrong earlier. Fix it up. */
291 			trans->type = optype;
292 		}
293 		if (optype != trans->type) {
294 			printf("ICH SPI: Transaction doesn't fit type %d\n",
295 			       optype);
296 			return -ENOSPC;
297 		}
298 		return opcode_index;
299 	}
300 }
301 
302 static int spi_setup_offset(struct spi_trans *trans)
303 {
304 	/* Separate the SPI address and data. */
305 	switch (trans->type) {
306 	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
307 	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
308 		return 0;
309 	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
310 	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
311 		trans->offset = ((uint32_t)trans->out[0] << 16) |
312 				((uint32_t)trans->out[1] << 8) |
313 				((uint32_t)trans->out[2] << 0);
314 		spi_use_out(trans, 3);
315 		return 1;
316 	default:
317 		printf("Unrecognized SPI transaction type %#x\n", trans->type);
318 		return -EPROTO;
319 	}
320 }
321 
322 /*
323  * Wait for up to 6s til status register bit(s) turn 1 (in case wait_til_set
324  * below is true) or 0. In case the wait was for the bit(s) to set - write
325  * those bits back, which would cause resetting them.
326  *
327  * Return the last read status value on success or -1 on failure.
328  */
329 static int ich_status_poll(struct ich_spi_priv *ctlr, u16 bitmask,
330 			   int wait_til_set)
331 {
332 	int timeout = 600000; /* This will result in 6s */
333 	u16 status = 0;
334 
335 	while (timeout--) {
336 		status = ich_readw(ctlr, ctlr->status);
337 		if (wait_til_set ^ ((status & bitmask) == 0)) {
338 			if (wait_til_set) {
339 				ich_writew(ctlr, status & bitmask,
340 					   ctlr->status);
341 			}
342 			return status;
343 		}
344 		udelay(10);
345 	}
346 
347 	printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
348 	       status, bitmask);
349 	return -ETIMEDOUT;
350 }
351 
352 static int ich_spi_xfer(struct udevice *dev, unsigned int bitlen,
353 			const void *dout, void *din, unsigned long flags)
354 {
355 	struct udevice *bus = dev_get_parent(dev);
356 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
357 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
358 	uint16_t control;
359 	int16_t opcode_index;
360 	int with_address;
361 	int status;
362 	int bytes = bitlen / 8;
363 	struct spi_trans *trans = &ctlr->trans;
364 	unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
365 	int using_cmd = 0;
366 	int ret;
367 
368 	/* We don't support writing partial bytes */
369 	if (bitlen % 8) {
370 		debug("ICH SPI: Accessing partial bytes not supported\n");
371 		return -EPROTONOSUPPORT;
372 	}
373 
374 	/* An empty end transaction can be ignored */
375 	if (type == SPI_XFER_END && !dout && !din)
376 		return 0;
377 
378 	if (type & SPI_XFER_BEGIN)
379 		memset(trans, '\0', sizeof(*trans));
380 
381 	/* Dp we need to come back later to finish it? */
382 	if (dout && type == SPI_XFER_BEGIN) {
383 		if (bytes > ICH_MAX_CMD_LEN) {
384 			debug("ICH SPI: Command length limit exceeded\n");
385 			return -ENOSPC;
386 		}
387 		memcpy(trans->cmd, dout, bytes);
388 		trans->cmd_len = bytes;
389 		debug_trace("ICH SPI: Saved %d bytes\n", bytes);
390 		return 0;
391 	}
392 
393 	/*
394 	 * We process a 'middle' spi_xfer() call, which has no
395 	 * SPI_XFER_BEGIN/END, as an independent transaction as if it had
396 	 * an end. We therefore repeat the command. This is because ICH
397 	 * seems to have no support for this, or because interest (in digging
398 	 * out the details and creating a special case in the code) is low.
399 	 */
400 	if (trans->cmd_len) {
401 		trans->out = trans->cmd;
402 		trans->bytesout = trans->cmd_len;
403 		using_cmd = 1;
404 		debug_trace("ICH SPI: Using %d bytes\n", trans->cmd_len);
405 	} else {
406 		trans->out = dout;
407 		trans->bytesout = dout ? bytes : 0;
408 	}
409 
410 	trans->in = din;
411 	trans->bytesin = din ? bytes : 0;
412 
413 	/* There has to always at least be an opcode. */
414 	if (!trans->bytesout) {
415 		debug("ICH SPI: No opcode for transfer\n");
416 		return -EPROTO;
417 	}
418 
419 	ret = ich_status_poll(ctlr, SPIS_SCIP, 0);
420 	if (ret < 0)
421 		return ret;
422 
423 	if (plat->ich_version == PCHV_7)
424 		ich_writew(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
425 	else
426 		ich_writeb(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
427 
428 	spi_setup_type(trans, using_cmd ? bytes : 0);
429 	opcode_index = spi_setup_opcode(ctlr, trans);
430 	if (opcode_index < 0)
431 		return -EINVAL;
432 	with_address = spi_setup_offset(trans);
433 	if (with_address < 0)
434 		return -EINVAL;
435 
436 	if (trans->opcode == SPI_OPCODE_WREN) {
437 		/*
438 		 * Treat Write Enable as Atomic Pre-Op if possible
439 		 * in order to prevent the Management Engine from
440 		 * issuing a transaction between WREN and DATA.
441 		 */
442 		if (!ctlr->ichspi_lock)
443 			ich_writew(ctlr, trans->opcode, ctlr->preop);
444 		return 0;
445 	}
446 
447 	if (ctlr->speed && ctlr->max_speed >= 33000000) {
448 		int byte;
449 
450 		byte = ich_readb(ctlr, ctlr->speed);
451 		if (ctlr->cur_speed >= 33000000)
452 			byte |= SSFC_SCF_33MHZ;
453 		else
454 			byte &= ~SSFC_SCF_33MHZ;
455 		ich_writeb(ctlr, byte, ctlr->speed);
456 	}
457 
458 	/* See if we have used up the command data */
459 	if (using_cmd && dout && bytes) {
460 		trans->out = dout;
461 		trans->bytesout = bytes;
462 		debug_trace("ICH SPI: Moving to data, %d bytes\n", bytes);
463 	}
464 
465 	/* Preset control fields */
466 	control = ich_readw(ctlr, ctlr->control);
467 	control &= ~SSFC_RESERVED;
468 	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
469 
470 	/* Issue atomic preop cycle if needed */
471 	if (ich_readw(ctlr, ctlr->preop))
472 		control |= SPIC_ACS;
473 
474 	if (!trans->bytesout && !trans->bytesin) {
475 		/* SPI addresses are 24 bit only */
476 		if (with_address) {
477 			ich_writel(ctlr, trans->offset & 0x00FFFFFF,
478 				   ctlr->addr);
479 		}
480 		/*
481 		 * This is a 'no data' command (like Write Enable), its
482 		 * bitesout size was 1, decremented to zero while executing
483 		 * spi_setup_opcode() above. Tell the chip to send the
484 		 * command.
485 		 */
486 		ich_writew(ctlr, control, ctlr->control);
487 
488 		/* wait for the result */
489 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
490 		if (status < 0)
491 			return status;
492 
493 		if (status & SPIS_FCERR) {
494 			debug("ICH SPI: Command transaction error\n");
495 			return -EIO;
496 		}
497 
498 		return 0;
499 	}
500 
501 	/*
502 	 * Check if this is a write command atempting to transfer more bytes
503 	 * than the controller can handle. Iterations for writes are not
504 	 * supported here because each SPI write command needs to be preceded
505 	 * and followed by other SPI commands, and this sequence is controlled
506 	 * by the SPI chip driver.
507 	 */
508 	if (trans->bytesout > ctlr->databytes) {
509 		debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
510 		return -EPROTO;
511 	}
512 
513 	/*
514 	 * Read or write up to databytes bytes at a time until everything has
515 	 * been sent.
516 	 */
517 	while (trans->bytesout || trans->bytesin) {
518 		uint32_t data_length;
519 
520 		/* SPI addresses are 24 bit only */
521 		ich_writel(ctlr, trans->offset & 0x00FFFFFF, ctlr->addr);
522 
523 		if (trans->bytesout)
524 			data_length = min(trans->bytesout, ctlr->databytes);
525 		else
526 			data_length = min(trans->bytesin, ctlr->databytes);
527 
528 		/* Program data into FDATA0 to N */
529 		if (trans->bytesout) {
530 			write_reg(ctlr, trans->out, ctlr->data, data_length);
531 			spi_use_out(trans, data_length);
532 			if (with_address)
533 				trans->offset += data_length;
534 		}
535 
536 		/* Add proper control fields' values */
537 		control &= ~((ctlr->databytes - 1) << 8);
538 		control |= SPIC_DS;
539 		control |= (data_length - 1) << 8;
540 
541 		/* write it */
542 		ich_writew(ctlr, control, ctlr->control);
543 
544 		/* Wait for Cycle Done Status or Flash Cycle Error. */
545 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
546 		if (status < 0)
547 			return status;
548 
549 		if (status & SPIS_FCERR) {
550 			debug("ICH SPI: Data transaction error %x\n", status);
551 			return -EIO;
552 		}
553 
554 		if (trans->bytesin) {
555 			read_reg(ctlr, ctlr->data, trans->in, data_length);
556 			spi_use_in(trans, data_length);
557 			if (with_address)
558 				trans->offset += data_length;
559 		}
560 	}
561 
562 	/* Clear atomic preop now that xfer is done */
563 	ich_writew(ctlr, 0, ctlr->preop);
564 
565 	return 0;
566 }
567 
568 /*
569  * This uses the SPI controller from the Intel Cougar Point and Panther Point
570  * PCH to write-protect portions of the SPI flash until reboot. The changes
571  * don't actually take effect until the HSFS[FLOCKDN] bit is set, but that's
572  * done elsewhere.
573  */
574 int spi_write_protect_region(struct udevice *dev, uint32_t lower_limit,
575 			     uint32_t length, int hint)
576 {
577 	struct udevice *bus = dev->parent;
578 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
579 	uint32_t tmplong;
580 	uint32_t upper_limit;
581 
582 	if (!ctlr->pr) {
583 		printf("%s: operation not supported on this chipset\n",
584 		       __func__);
585 		return -ENOSYS;
586 	}
587 
588 	if (length == 0 ||
589 	    lower_limit > (0xFFFFFFFFUL - length) + 1 ||
590 	    hint < 0 || hint > 4) {
591 		printf("%s(0x%x, 0x%x, %d): invalid args\n", __func__,
592 		       lower_limit, length, hint);
593 		return -EPERM;
594 	}
595 
596 	upper_limit = lower_limit + length - 1;
597 
598 	/*
599 	 * Determine bits to write, as follows:
600 	 *  31     Write-protection enable (includes erase operation)
601 	 *  30:29  reserved
602 	 *  28:16  Upper Limit (FLA address bits 24:12, with 11:0 == 0xfff)
603 	 *  15     Read-protection enable
604 	 *  14:13  reserved
605 	 *  12:0   Lower Limit (FLA address bits 24:12, with 11:0 == 0x000)
606 	 */
607 	tmplong = 0x80000000 |
608 		((upper_limit & 0x01fff000) << 4) |
609 		((lower_limit & 0x01fff000) >> 12);
610 
611 	printf("%s: writing 0x%08x to %p\n", __func__, tmplong,
612 	       &ctlr->pr[hint]);
613 	ctlr->pr[hint] = tmplong;
614 
615 	return 0;
616 }
617 
618 static int ich_spi_probe(struct udevice *dev)
619 {
620 	struct ich_spi_platdata *plat = dev_get_platdata(dev);
621 	struct ich_spi_priv *priv = dev_get_priv(dev);
622 	uint8_t bios_cntl;
623 	int ret;
624 
625 	/* Check the ICH version */
626 	plat->ich_version = pch_get_version(dev->parent);
627 
628 	ret = ich_init_controller(dev, plat, priv);
629 	if (ret)
630 		return ret;
631 	/* Disable the BIOS write protect so write commands are allowed */
632 	ret = pch_set_spi_protect(dev->parent, false);
633 	if (ret == -ENOSYS) {
634 		bios_cntl = ich_readb(priv, priv->bcr);
635 		bios_cntl &= ~BIT(5);	/* clear Enable InSMM_STS (EISS) */
636 		bios_cntl |= 1;		/* Write Protect Disable (WPD) */
637 		ich_writeb(priv, bios_cntl, priv->bcr);
638 	} else if (ret) {
639 		debug("%s: Failed to disable write-protect: err=%d\n",
640 		      __func__, ret);
641 		return ret;
642 	}
643 
644 	priv->cur_speed = priv->max_speed;
645 
646 	return 0;
647 }
648 
649 static int ich_spi_set_speed(struct udevice *bus, uint speed)
650 {
651 	struct ich_spi_priv *priv = dev_get_priv(bus);
652 
653 	priv->cur_speed = speed;
654 
655 	return 0;
656 }
657 
658 static int ich_spi_set_mode(struct udevice *bus, uint mode)
659 {
660 	debug("%s: mode=%d\n", __func__, mode);
661 
662 	return 0;
663 }
664 
665 static int ich_spi_child_pre_probe(struct udevice *dev)
666 {
667 	struct udevice *bus = dev_get_parent(dev);
668 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
669 	struct ich_spi_priv *priv = dev_get_priv(bus);
670 	struct spi_slave *slave = dev_get_parent_priv(dev);
671 
672 	/*
673 	 * Yes this controller can only write a small number of bytes at
674 	 * once! The limit is typically 64 bytes.
675 	 */
676 	slave->max_write_size = priv->databytes;
677 	/*
678 	 * ICH 7 SPI controller only supports array read command
679 	 * and byte program command for SST flash
680 	 */
681 	if (plat->ich_version == PCHV_7) {
682 		slave->mode_rx = SPI_RX_SLOW;
683 		slave->mode = SPI_TX_BYTE;
684 	}
685 
686 	return 0;
687 }
688 
689 static const struct dm_spi_ops ich_spi_ops = {
690 	.xfer		= ich_spi_xfer,
691 	.set_speed	= ich_spi_set_speed,
692 	.set_mode	= ich_spi_set_mode,
693 	/*
694 	 * cs_info is not needed, since we require all chip selects to be
695 	 * in the device tree explicitly
696 	 */
697 };
698 
699 static const struct udevice_id ich_spi_ids[] = {
700 	{ .compatible = "intel,ich-spi" },
701 	{ }
702 };
703 
704 U_BOOT_DRIVER(ich_spi) = {
705 	.name	= "ich_spi",
706 	.id	= UCLASS_SPI,
707 	.of_match = ich_spi_ids,
708 	.ops	= &ich_spi_ops,
709 	.platdata_auto_alloc_size = sizeof(struct ich_spi_platdata),
710 	.priv_auto_alloc_size = sizeof(struct ich_spi_priv),
711 	.child_pre_probe = ich_spi_child_pre_probe,
712 	.probe	= ich_spi_probe,
713 };
714