xref: /openbmc/u-boot/drivers/spi/ich.c (revision 68fbc0e6)
1 /*
2  * Copyright (c) 2011-12 The Chromium OS Authors.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of
7  * the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but without any warranty; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
17  * MA 02111-1307 USA
18  *
19  * This file is derived from the flashrom project.
20  */
21 
22 #include <common.h>
23 #include <malloc.h>
24 #include <spi.h>
25 #include <pci.h>
26 #include <pci_ids.h>
27 #include <asm/io.h>
28 
29 #include "ich.h"
30 
31 #define SPI_OPCODE_WREN      0x06
32 #define SPI_OPCODE_FAST_READ 0x0b
33 
34 struct ich_ctlr {
35 	pci_dev_t dev;		/* PCI device number */
36 	int ich_version;	/* Controller version, 7 or 9 */
37 	int ichspi_lock;
38 	int locked;
39 	uint8_t *opmenu;
40 	int menubytes;
41 	void *base;		/* Base of register set */
42 	uint16_t *preop;
43 	uint16_t *optype;
44 	uint32_t *addr;
45 	uint8_t *data;
46 	unsigned databytes;
47 	uint8_t *status;
48 	uint16_t *control;
49 	uint32_t *bbar;
50 	uint32_t *pr;		/* only for ich9 */
51 	uint8_t *speed;		/* pointer to speed control */
52 	ulong max_speed;	/* Maximum bus speed in MHz */
53 };
54 
55 struct ich_ctlr ctlr;
56 
57 static inline struct ich_spi_slave *to_ich_spi(struct spi_slave *slave)
58 {
59 	return container_of(slave, struct ich_spi_slave, slave);
60 }
61 
62 static unsigned int ich_reg(const void *addr)
63 {
64 	return (unsigned)(addr - ctlr.base) & 0xffff;
65 }
66 
67 static u8 ich_readb(const void *addr)
68 {
69 	u8 value = readb(addr);
70 
71 	debug("read %2.2x from %4.4x\n", value, ich_reg(addr));
72 
73 	return value;
74 }
75 
76 static u16 ich_readw(const void *addr)
77 {
78 	u16 value = readw(addr);
79 
80 	debug("read %4.4x from %4.4x\n", value, ich_reg(addr));
81 
82 	return value;
83 }
84 
85 static u32 ich_readl(const void *addr)
86 {
87 	u32 value = readl(addr);
88 
89 	debug("read %8.8x from %4.4x\n", value, ich_reg(addr));
90 
91 	return value;
92 }
93 
94 static void ich_writeb(u8 value, void *addr)
95 {
96 	writeb(value, addr);
97 	debug("wrote %2.2x to %4.4x\n", value, ich_reg(addr));
98 }
99 
100 static void ich_writew(u16 value, void *addr)
101 {
102 	writew(value, addr);
103 	debug("wrote %4.4x to %4.4x\n", value, ich_reg(addr));
104 }
105 
106 static void ich_writel(u32 value, void *addr)
107 {
108 	writel(value, addr);
109 	debug("wrote %8.8x to %4.4x\n", value, ich_reg(addr));
110 }
111 
112 static void write_reg(const void *value, void *dest, uint32_t size)
113 {
114 	memcpy_toio(dest, value, size);
115 }
116 
117 static void read_reg(const void *src, void *value, uint32_t size)
118 {
119 	memcpy_fromio(value, src, size);
120 }
121 
122 static void ich_set_bbar(struct ich_ctlr *ctlr, uint32_t minaddr)
123 {
124 	const uint32_t bbar_mask = 0x00ffff00;
125 	uint32_t ichspi_bbar;
126 
127 	minaddr &= bbar_mask;
128 	ichspi_bbar = ich_readl(ctlr->bbar) & ~bbar_mask;
129 	ichspi_bbar |= minaddr;
130 	ich_writel(ichspi_bbar, ctlr->bbar);
131 }
132 
133 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
134 {
135 	puts("spi_cs_is_valid used but not implemented\n");
136 	return 0;
137 }
138 
139 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
140 		unsigned int max_hz, unsigned int mode)
141 {
142 	struct ich_spi_slave *ich;
143 
144 	ich = spi_alloc_slave(struct ich_spi_slave, bus, cs);
145 	if (!ich) {
146 		puts("ICH SPI: Out of memory\n");
147 		return NULL;
148 	}
149 
150 	/*
151 	 * Yes this controller can only write a small number of bytes at
152 	 * once! The limit is typically 64 bytes.
153 	 */
154 	ich->slave.max_write_size = ctlr.databytes;
155 	ich->speed = max_hz;
156 
157 	return &ich->slave;
158 }
159 
160 void spi_free_slave(struct spi_slave *slave)
161 {
162 	struct ich_spi_slave *ich = to_ich_spi(slave);
163 
164 	free(ich);
165 }
166 
167 /*
168  * Check if this device ID matches one of supported Intel PCH devices.
169  *
170  * Return the ICH version if there is a match, or zero otherwise.
171  */
172 static int get_ich_version(uint16_t device_id)
173 {
174 	if (device_id == PCI_DEVICE_ID_INTEL_TGP_LPC)
175 		return 7;
176 
177 	if ((device_id >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
178 	     device_id <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX) ||
179 	    (device_id >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
180 	     device_id <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX))
181 		return 9;
182 
183 	return 0;
184 }
185 
186 /* @return 1 if the SPI flash supports the 33MHz speed */
187 static int ich9_can_do_33mhz(pci_dev_t dev)
188 {
189 	u32 fdod, speed;
190 
191 	/* Observe SPI Descriptor Component Section 0 */
192 	pci_write_config_dword(dev, 0xb0, 0x1000);
193 
194 	/* Extract the Write/Erase SPI Frequency from descriptor */
195 	pci_read_config_dword(dev, 0xb4, &fdod);
196 
197 	/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
198 	speed = (fdod >> 21) & 7;
199 
200 	return speed == 1;
201 }
202 
203 static int ich_find_spi_controller(pci_dev_t *devp, int *ich_versionp)
204 {
205 	int last_bus = pci_last_busno();
206 	int bus;
207 
208 	if (last_bus == -1) {
209 		debug("No PCI busses?\n");
210 		return -1;
211 	}
212 
213 	for (bus = 0; bus <= last_bus; bus++) {
214 		uint16_t vendor_id, device_id;
215 		uint32_t ids;
216 		pci_dev_t dev;
217 
218 		dev = PCI_BDF(bus, 31, 0);
219 		pci_read_config_dword(dev, 0, &ids);
220 		vendor_id = ids;
221 		device_id = ids >> 16;
222 
223 		if (vendor_id == PCI_VENDOR_ID_INTEL) {
224 			*devp = dev;
225 			*ich_versionp = get_ich_version(device_id);
226 			return 0;
227 		}
228 	}
229 
230 	debug("ICH SPI: No ICH found.\n");
231 	return -1;
232 }
233 
234 static int ich_init_controller(struct ich_ctlr *ctlr)
235 {
236 	uint8_t *rcrb; /* Root Complex Register Block */
237 	uint32_t rcba; /* Root Complex Base Address */
238 
239 	pci_read_config_dword(ctlr->dev, 0xf0, &rcba);
240 	/* Bits 31-14 are the base address, 13-1 are reserved, 0 is enable. */
241 	rcrb = (uint8_t *)(rcba & 0xffffc000);
242 	if (ctlr->ich_version == 7) {
243 		struct ich7_spi_regs *ich7_spi;
244 
245 		ich7_spi = (struct ich7_spi_regs *)(rcrb + 0x3020);
246 		ctlr->ichspi_lock = ich_readw(&ich7_spi->spis) & SPIS_LOCK;
247 		ctlr->opmenu = ich7_spi->opmenu;
248 		ctlr->menubytes = sizeof(ich7_spi->opmenu);
249 		ctlr->optype = &ich7_spi->optype;
250 		ctlr->addr = &ich7_spi->spia;
251 		ctlr->data = (uint8_t *)ich7_spi->spid;
252 		ctlr->databytes = sizeof(ich7_spi->spid);
253 		ctlr->status = (uint8_t *)&ich7_spi->spis;
254 		ctlr->control = &ich7_spi->spic;
255 		ctlr->bbar = &ich7_spi->bbar;
256 		ctlr->preop = &ich7_spi->preop;
257 		ctlr->base = ich7_spi;
258 	} else if (ctlr->ich_version == 9) {
259 		struct ich9_spi_regs *ich9_spi;
260 
261 		ich9_spi = (struct ich9_spi_regs *)(rcrb + 0x3800);
262 		ctlr->ichspi_lock = ich_readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
263 		ctlr->opmenu = ich9_spi->opmenu;
264 		ctlr->menubytes = sizeof(ich9_spi->opmenu);
265 		ctlr->optype = &ich9_spi->optype;
266 		ctlr->addr = &ich9_spi->faddr;
267 		ctlr->data = (uint8_t *)ich9_spi->fdata;
268 		ctlr->databytes = sizeof(ich9_spi->fdata);
269 		ctlr->status = &ich9_spi->ssfs;
270 		ctlr->control = (uint16_t *)ich9_spi->ssfc;
271 		ctlr->speed = ich9_spi->ssfc + 2;
272 		ctlr->bbar = &ich9_spi->bbar;
273 		ctlr->preop = &ich9_spi->preop;
274 		ctlr->pr = &ich9_spi->pr[0];
275 		ctlr->base = ich9_spi;
276 	} else {
277 		debug("ICH SPI: Unrecognized ICH version %d.\n",
278 		      ctlr->ich_version);
279 		return -1;
280 	}
281 	debug("ICH SPI: Version %d detected\n", ctlr->ich_version);
282 
283 	/* Work out the maximum speed we can support */
284 	ctlr->max_speed = 20000000;
285 	if (ctlr->ich_version == 9 && ich9_can_do_33mhz(ctlr->dev))
286 		ctlr->max_speed = 33000000;
287 
288 	ich_set_bbar(ctlr, 0);
289 
290 	return 0;
291 }
292 
293 void spi_init(void)
294 {
295 	uint8_t bios_cntl;
296 
297 	if (ich_find_spi_controller(&ctlr.dev, &ctlr.ich_version)) {
298 		printf("ICH SPI: Cannot find device\n");
299 		return;
300 	}
301 
302 	if (ich_init_controller(&ctlr)) {
303 		printf("ICH SPI: Cannot setup controller\n");
304 		return;
305 	}
306 
307 	/*
308 	 * Disable the BIOS write protect so write commands are allowed.  On
309 	 * v9, deassert SMM BIOS Write Protect Disable.
310 	 */
311 	pci_read_config_byte(ctlr.dev, 0xdc, &bios_cntl);
312 	if (ctlr.ich_version == 9)
313 		bios_cntl &= ~(1 << 5);
314 	pci_write_config_byte(ctlr.dev, 0xdc, bios_cntl | 0x1);
315 }
316 
317 int spi_claim_bus(struct spi_slave *slave)
318 {
319 	/* Handled by ICH automatically. */
320 	return 0;
321 }
322 
323 void spi_release_bus(struct spi_slave *slave)
324 {
325 	/* Handled by ICH automatically. */
326 }
327 
328 void spi_cs_activate(struct spi_slave *slave)
329 {
330 	/* Handled by ICH automatically. */
331 }
332 
333 void spi_cs_deactivate(struct spi_slave *slave)
334 {
335 	/* Handled by ICH automatically. */
336 }
337 
338 static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
339 {
340 	trans->out += bytes;
341 	trans->bytesout -= bytes;
342 }
343 
344 static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
345 {
346 	trans->in += bytes;
347 	trans->bytesin -= bytes;
348 }
349 
350 static void spi_setup_type(struct spi_trans *trans, int data_bytes)
351 {
352 	trans->type = 0xFF;
353 
354 	/* Try to guess spi type from read/write sizes. */
355 	if (trans->bytesin == 0) {
356 		if (trans->bytesout + data_bytes > 4)
357 			/*
358 			 * If bytesin = 0 and bytesout > 4, we presume this is
359 			 * a write data operation, which is accompanied by an
360 			 * address.
361 			 */
362 			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
363 		else
364 			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
365 		return;
366 	}
367 
368 	if (trans->bytesout == 1) {	/* and bytesin is > 0 */
369 		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
370 		return;
371 	}
372 
373 	if (trans->bytesout == 4)	/* and bytesin is > 0 */
374 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
375 
376 	/* Fast read command is called with 5 bytes instead of 4 */
377 	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
378 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
379 		--trans->bytesout;
380 	}
381 }
382 
383 static int spi_setup_opcode(struct spi_trans *trans)
384 {
385 	uint16_t optypes;
386 	uint8_t opmenu[ctlr.menubytes];
387 
388 	trans->opcode = trans->out[0];
389 	spi_use_out(trans, 1);
390 	if (!ctlr.ichspi_lock) {
391 		/* The lock is off, so just use index 0. */
392 		ich_writeb(trans->opcode, ctlr.opmenu);
393 		optypes = ich_readw(ctlr.optype);
394 		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
395 		ich_writew(optypes, ctlr.optype);
396 		return 0;
397 	} else {
398 		/* The lock is on. See if what we need is on the menu. */
399 		uint8_t optype;
400 		uint16_t opcode_index;
401 
402 		/* Write Enable is handled as atomic prefix */
403 		if (trans->opcode == SPI_OPCODE_WREN)
404 			return 0;
405 
406 		read_reg(ctlr.opmenu, opmenu, sizeof(opmenu));
407 		for (opcode_index = 0; opcode_index < ctlr.menubytes;
408 				opcode_index++) {
409 			if (opmenu[opcode_index] == trans->opcode)
410 				break;
411 		}
412 
413 		if (opcode_index == ctlr.menubytes) {
414 			printf("ICH SPI: Opcode %x not found\n",
415 			       trans->opcode);
416 			return -1;
417 		}
418 
419 		optypes = ich_readw(ctlr.optype);
420 		optype = (optypes >> (opcode_index * 2)) & 0x3;
421 		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
422 		    optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
423 		    trans->bytesout >= 3) {
424 			/* We guessed wrong earlier. Fix it up. */
425 			trans->type = optype;
426 		}
427 		if (optype != trans->type) {
428 			printf("ICH SPI: Transaction doesn't fit type %d\n",
429 			       optype);
430 			return -1;
431 		}
432 		return opcode_index;
433 	}
434 }
435 
436 static int spi_setup_offset(struct spi_trans *trans)
437 {
438 	/* Separate the SPI address and data. */
439 	switch (trans->type) {
440 	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
441 	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
442 		return 0;
443 	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
444 	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
445 		trans->offset = ((uint32_t)trans->out[0] << 16) |
446 				((uint32_t)trans->out[1] << 8) |
447 				((uint32_t)trans->out[2] << 0);
448 		spi_use_out(trans, 3);
449 		return 1;
450 	default:
451 		printf("Unrecognized SPI transaction type %#x\n", trans->type);
452 		return -1;
453 	}
454 }
455 
456 /*
457  * Wait for up to 6s til status register bit(s) turn 1 (in case wait_til_set
458  * below is True) or 0. In case the wait was for the bit(s) to set - write
459  * those bits back, which would cause resetting them.
460  *
461  * Return the last read status value on success or -1 on failure.
462  */
463 static int ich_status_poll(u16 bitmask, int wait_til_set)
464 {
465 	int timeout = 600000; /* This will result in 6s */
466 	u16 status = 0;
467 
468 	while (timeout--) {
469 		status = ich_readw(ctlr.status);
470 		if (wait_til_set ^ ((status & bitmask) == 0)) {
471 			if (wait_til_set)
472 				ich_writew((status & bitmask), ctlr.status);
473 			return status;
474 		}
475 		udelay(10);
476 	}
477 
478 	printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
479 	       status, bitmask);
480 	return -1;
481 }
482 
483 /*
484 int spi_xfer(struct spi_slave *slave, const void *dout,
485 		unsigned int bitsout, void *din, unsigned int bitsin)
486 */
487 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
488 		void *din, unsigned long flags)
489 {
490 	struct ich_spi_slave *ich = to_ich_spi(slave);
491 	uint16_t control;
492 	int16_t opcode_index;
493 	int with_address;
494 	int status;
495 	int bytes = bitlen / 8;
496 	struct spi_trans *trans = &ich->trans;
497 	unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
498 	int using_cmd = 0;
499 	/* Align read transactions to 64-byte boundaries */
500 	char buff[ctlr.databytes];
501 
502 	/* Ee don't support writing partial bytes. */
503 	if (bitlen % 8) {
504 		debug("ICH SPI: Accessing partial bytes not supported\n");
505 		return -1;
506 	}
507 
508 	/* An empty end transaction can be ignored */
509 	if (type == SPI_XFER_END && !dout && !din)
510 		return 0;
511 
512 	if (type & SPI_XFER_BEGIN)
513 		memset(trans, '\0', sizeof(*trans));
514 
515 	/* Dp we need to come back later to finish it? */
516 	if (dout && type == SPI_XFER_BEGIN) {
517 		if (bytes > ICH_MAX_CMD_LEN) {
518 			debug("ICH SPI: Command length limit exceeded\n");
519 			return -1;
520 		}
521 		memcpy(trans->cmd, dout, bytes);
522 		trans->cmd_len = bytes;
523 		debug("ICH SPI: Saved %d bytes\n", bytes);
524 		return 0;
525 	}
526 
527 	/*
528 	 * We process a 'middle' spi_xfer() call, which has no
529 	 * SPI_XFER_BEGIN/END, as an independent transaction as if it had
530 	 * an end. We therefore repeat the command. This is because ICH
531 	 * seems to have no support for this, or because interest (in digging
532 	 * out the details and creating a special case in the code) is low.
533 	 */
534 	if (trans->cmd_len) {
535 		trans->out = trans->cmd;
536 		trans->bytesout = trans->cmd_len;
537 		using_cmd = 1;
538 		debug("ICH SPI: Using %d bytes\n", trans->cmd_len);
539 	} else {
540 		trans->out = dout;
541 		trans->bytesout = dout ? bytes : 0;
542 	}
543 
544 	trans->in = din;
545 	trans->bytesin = din ? bytes : 0;
546 
547 	/* There has to always at least be an opcode. */
548 	if (!trans->bytesout) {
549 		debug("ICH SPI: No opcode for transfer\n");
550 		return -1;
551 	}
552 
553 	if (ich_status_poll(SPIS_SCIP, 0) == -1)
554 		return -1;
555 
556 	ich_writew(SPIS_CDS | SPIS_FCERR, ctlr.status);
557 
558 	spi_setup_type(trans, using_cmd ? bytes : 0);
559 	opcode_index = spi_setup_opcode(trans);
560 	if (opcode_index < 0)
561 		return -1;
562 	with_address = spi_setup_offset(trans);
563 	if (with_address < 0)
564 		return -1;
565 
566 	if (trans->opcode == SPI_OPCODE_WREN) {
567 		/*
568 		 * Treat Write Enable as Atomic Pre-Op if possible
569 		 * in order to prevent the Management Engine from
570 		 * issuing a transaction between WREN and DATA.
571 		 */
572 		if (!ctlr.ichspi_lock)
573 			ich_writew(trans->opcode, ctlr.preop);
574 		return 0;
575 	}
576 
577 	if (ctlr.speed && ctlr.max_speed >= 33000000) {
578 		int byte;
579 
580 		byte = ich_readb(ctlr.speed);
581 		if (ich->speed >= 33000000)
582 			byte |= SSFC_SCF_33MHZ;
583 		else
584 			byte &= ~SSFC_SCF_33MHZ;
585 		ich_writeb(byte, ctlr.speed);
586 	}
587 
588 	/* See if we have used up the command data */
589 	if (using_cmd && dout && bytes) {
590 		trans->out = dout;
591 		trans->bytesout = bytes;
592 		debug("ICH SPI: Moving to data, %d bytes\n", bytes);
593 	}
594 
595 	/* Preset control fields */
596 	control = ich_readw(ctlr.control);
597 	control &= ~SSFC_RESERVED;
598 	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
599 
600 	/* Issue atomic preop cycle if needed */
601 	if (ich_readw(ctlr.preop))
602 		control |= SPIC_ACS;
603 
604 	if (!trans->bytesout && !trans->bytesin) {
605 		/* SPI addresses are 24 bit only */
606 		if (with_address)
607 			ich_writel(trans->offset & 0x00FFFFFF, ctlr.addr);
608 
609 		/*
610 		 * This is a 'no data' command (like Write Enable), its
611 		 * bitesout size was 1, decremented to zero while executing
612 		 * spi_setup_opcode() above. Tell the chip to send the
613 		 * command.
614 		 */
615 		ich_writew(control, ctlr.control);
616 
617 		/* wait for the result */
618 		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
619 		if (status == -1)
620 			return -1;
621 
622 		if (status & SPIS_FCERR) {
623 			debug("ICH SPI: Command transaction error\n");
624 			return -1;
625 		}
626 
627 		return 0;
628 	}
629 
630 	/*
631 	 * Check if this is a write command atempting to transfer more bytes
632 	 * than the controller can handle. Iterations for writes are not
633 	 * supported here because each SPI write command needs to be preceded
634 	 * and followed by other SPI commands, and this sequence is controlled
635 	 * by the SPI chip driver.
636 	 */
637 	if (trans->bytesout > ctlr.databytes) {
638 		debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
639 		return -1;
640 	}
641 
642 	/*
643 	 * Read or write up to databytes bytes at a time until everything has
644 	 * been sent.
645 	 */
646 	while (trans->bytesout || trans->bytesin) {
647 		uint32_t data_length;
648 		uint32_t aligned_offset;
649 		uint32_t diff;
650 
651 		aligned_offset = trans->offset & ~(ctlr.databytes - 1);
652 		diff = trans->offset - aligned_offset;
653 
654 		/* SPI addresses are 24 bit only */
655 		ich_writel(aligned_offset & 0x00FFFFFF, ctlr.addr);
656 
657 		if (trans->bytesout)
658 			data_length = min(trans->bytesout, ctlr.databytes);
659 		else
660 			data_length = min(trans->bytesin, ctlr.databytes);
661 
662 		/* Program data into FDATA0 to N */
663 		if (trans->bytesout) {
664 			write_reg(trans->out, ctlr.data, data_length);
665 			spi_use_out(trans, data_length);
666 			if (with_address)
667 				trans->offset += data_length;
668 		}
669 
670 		/* Add proper control fields' values */
671 		control &= ~((ctlr.databytes - 1) << 8);
672 		control |= SPIC_DS;
673 		control |= (data_length - 1) << 8;
674 
675 		/* write it */
676 		ich_writew(control, ctlr.control);
677 
678 		/* Wait for Cycle Done Status or Flash Cycle Error. */
679 		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
680 		if (status == -1)
681 			return -1;
682 
683 		if (status & SPIS_FCERR) {
684 			debug("ICH SPI: Data transaction error\n");
685 			return -1;
686 		}
687 
688 		if (trans->bytesin) {
689 			if (diff) {
690 				data_length -= diff;
691 				read_reg(ctlr.data, buff, ctlr.databytes);
692 				memcpy(trans->in, buff + diff, data_length);
693 			} else {
694 				read_reg(ctlr.data, trans->in, data_length);
695 			}
696 			spi_use_in(trans, data_length);
697 			if (with_address)
698 				trans->offset += data_length;
699 		}
700 	}
701 
702 	/* Clear atomic preop now that xfer is done */
703 	ich_writew(0, ctlr.preop);
704 
705 	return 0;
706 }
707 
708 
709 /*
710  * This uses the SPI controller from the Intel Cougar Point and Panther Point
711  * PCH to write-protect portions of the SPI flash until reboot. The changes
712  * don't actually take effect until the HSFS[FLOCKDN] bit is set, but that's
713  * done elsewhere.
714  */
715 int spi_write_protect_region(uint32_t lower_limit, uint32_t length, int hint)
716 {
717 	uint32_t tmplong;
718 	uint32_t upper_limit;
719 
720 	if (!ctlr.pr) {
721 		printf("%s: operation not supported on this chipset\n",
722 		       __func__);
723 		return -1;
724 	}
725 
726 	if (length == 0 ||
727 	    lower_limit > (0xFFFFFFFFUL - length) + 1 ||
728 	    hint < 0 || hint > 4) {
729 		printf("%s(0x%x, 0x%x, %d): invalid args\n", __func__,
730 		       lower_limit, length, hint);
731 		return -1;
732 	}
733 
734 	upper_limit = lower_limit + length - 1;
735 
736 	/*
737 	 * Determine bits to write, as follows:
738 	 *  31     Write-protection enable (includes erase operation)
739 	 *  30:29  reserved
740 	 *  28:16  Upper Limit (FLA address bits 24:12, with 11:0 == 0xfff)
741 	 *  15     Read-protection enable
742 	 *  14:13  reserved
743 	 *  12:0   Lower Limit (FLA address bits 24:12, with 11:0 == 0x000)
744 	 */
745 	tmplong = 0x80000000 |
746 		((upper_limit & 0x01fff000) << 4) |
747 		((lower_limit & 0x01fff000) >> 12);
748 
749 	printf("%s: writing 0x%08x to %p\n", __func__, tmplong,
750 	       &ctlr.pr[hint]);
751 	ctlr.pr[hint] = tmplong;
752 
753 	return 0;
754 }
755