xref: /rk3399_rockchip-uboot/drivers/spi/ich.c (revision 2795573a8c9c62db7b4bcf4bddf54d73b6ae61d3)
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 <malloc.h>
11 #include <spi.h>
12 #include <pci.h>
13 #include <pci_ids.h>
14 #include <asm/io.h>
15 
16 #include "ich.h"
17 
18 #define SPI_OPCODE_WREN      0x06
19 #define SPI_OPCODE_FAST_READ 0x0b
20 
21 struct ich_ctlr {
22 	pci_dev_t dev;		/* PCI device number */
23 	int ich_version;	/* Controller version, 7 or 9 */
24 	int ichspi_lock;
25 	int locked;
26 	uint8_t *opmenu;
27 	int menubytes;
28 	void *base;		/* Base of register set */
29 	uint16_t *preop;
30 	uint16_t *optype;
31 	uint32_t *addr;
32 	uint8_t *data;
33 	unsigned databytes;
34 	uint8_t *status;
35 	uint16_t *control;
36 	uint32_t *bbar;
37 	uint32_t *pr;		/* only for ich9 */
38 	uint8_t *speed;		/* pointer to speed control */
39 	ulong max_speed;	/* Maximum bus speed in MHz */
40 };
41 
42 struct ich_ctlr ctlr;
43 
44 static inline struct ich_spi_slave *to_ich_spi(struct spi_slave *slave)
45 {
46 	return container_of(slave, struct ich_spi_slave, slave);
47 }
48 
49 static unsigned int ich_reg(const void *addr)
50 {
51 	return (unsigned)(addr - ctlr.base) & 0xffff;
52 }
53 
54 static u8 ich_readb(const void *addr)
55 {
56 	u8 value = readb(addr);
57 
58 	debug("read %2.2x from %4.4x\n", value, ich_reg(addr));
59 
60 	return value;
61 }
62 
63 static u16 ich_readw(const void *addr)
64 {
65 	u16 value = readw(addr);
66 
67 	debug("read %4.4x from %4.4x\n", value, ich_reg(addr));
68 
69 	return value;
70 }
71 
72 static u32 ich_readl(const void *addr)
73 {
74 	u32 value = readl(addr);
75 
76 	debug("read %8.8x from %4.4x\n", value, ich_reg(addr));
77 
78 	return value;
79 }
80 
81 static void ich_writeb(u8 value, void *addr)
82 {
83 	writeb(value, addr);
84 	debug("wrote %2.2x to %4.4x\n", value, ich_reg(addr));
85 }
86 
87 static void ich_writew(u16 value, void *addr)
88 {
89 	writew(value, addr);
90 	debug("wrote %4.4x to %4.4x\n", value, ich_reg(addr));
91 }
92 
93 static void ich_writel(u32 value, void *addr)
94 {
95 	writel(value, addr);
96 	debug("wrote %8.8x to %4.4x\n", value, ich_reg(addr));
97 }
98 
99 static void write_reg(const void *value, void *dest, uint32_t size)
100 {
101 	memcpy_toio(dest, value, size);
102 }
103 
104 static void read_reg(const void *src, void *value, uint32_t size)
105 {
106 	memcpy_fromio(value, src, size);
107 }
108 
109 static void ich_set_bbar(struct ich_ctlr *ctlr, uint32_t minaddr)
110 {
111 	const uint32_t bbar_mask = 0x00ffff00;
112 	uint32_t ichspi_bbar;
113 
114 	minaddr &= bbar_mask;
115 	ichspi_bbar = ich_readl(ctlr->bbar) & ~bbar_mask;
116 	ichspi_bbar |= minaddr;
117 	ich_writel(ichspi_bbar, ctlr->bbar);
118 }
119 
120 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
121 {
122 	puts("spi_cs_is_valid used but not implemented\n");
123 	return 0;
124 }
125 
126 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
127 		unsigned int max_hz, unsigned int mode)
128 {
129 	struct ich_spi_slave *ich;
130 
131 	ich = spi_alloc_slave(struct ich_spi_slave, bus, cs);
132 	if (!ich) {
133 		puts("ICH SPI: Out of memory\n");
134 		return NULL;
135 	}
136 
137 	/*
138 	 * Yes this controller can only write a small number of bytes at
139 	 * once! The limit is typically 64 bytes.
140 	 */
141 	ich->slave.max_write_size = ctlr.databytes;
142 	ich->speed = max_hz;
143 
144 	/*
145 	 * ICH 7 SPI controller only supports array read command
146 	 * and byte program command for SST flash
147 	 */
148 	if (ctlr.ich_version == 7) {
149 		ich->slave.op_mode_rx = SPI_OPM_RX_AS;
150 		ich->slave.op_mode_tx = SPI_OPM_TX_BP;
151 	}
152 
153 	return &ich->slave;
154 }
155 
156 void spi_free_slave(struct spi_slave *slave)
157 {
158 	struct ich_spi_slave *ich = to_ich_spi(slave);
159 
160 	free(ich);
161 }
162 
163 /*
164  * Check if this device ID matches one of supported Intel PCH devices.
165  *
166  * Return the ICH version if there is a match, or zero otherwise.
167  */
168 static int get_ich_version(uint16_t device_id)
169 {
170 	if (device_id == PCI_DEVICE_ID_INTEL_TGP_LPC)
171 		return 7;
172 
173 	if ((device_id >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
174 	     device_id <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX) ||
175 	    (device_id >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
176 	     device_id <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX))
177 		return 9;
178 
179 	return 0;
180 }
181 
182 /* @return 1 if the SPI flash supports the 33MHz speed */
183 static int ich9_can_do_33mhz(pci_dev_t dev)
184 {
185 	u32 fdod, speed;
186 
187 	/* Observe SPI Descriptor Component Section 0 */
188 	pci_write_config_dword(dev, 0xb0, 0x1000);
189 
190 	/* Extract the Write/Erase SPI Frequency from descriptor */
191 	pci_read_config_dword(dev, 0xb4, &fdod);
192 
193 	/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
194 	speed = (fdod >> 21) & 7;
195 
196 	return speed == 1;
197 }
198 
199 static int ich_find_spi_controller(pci_dev_t *devp, int *ich_versionp)
200 {
201 	int last_bus = pci_last_busno();
202 	int bus;
203 
204 	if (last_bus == -1) {
205 		debug("No PCI busses?\n");
206 		return -1;
207 	}
208 
209 	for (bus = 0; bus <= last_bus; bus++) {
210 		uint16_t vendor_id, device_id;
211 		uint32_t ids;
212 		pci_dev_t dev;
213 
214 		dev = PCI_BDF(bus, 31, 0);
215 		pci_read_config_dword(dev, 0, &ids);
216 		vendor_id = ids;
217 		device_id = ids >> 16;
218 
219 		if (vendor_id == PCI_VENDOR_ID_INTEL) {
220 			*devp = dev;
221 			*ich_versionp = get_ich_version(device_id);
222 			return 0;
223 		}
224 	}
225 
226 	debug("ICH SPI: No ICH found.\n");
227 	return -1;
228 }
229 
230 static int ich_init_controller(struct ich_ctlr *ctlr)
231 {
232 	uint8_t *rcrb; /* Root Complex Register Block */
233 	uint32_t rcba; /* Root Complex Base Address */
234 
235 	pci_read_config_dword(ctlr->dev, 0xf0, &rcba);
236 	/* Bits 31-14 are the base address, 13-1 are reserved, 0 is enable. */
237 	rcrb = (uint8_t *)(rcba & 0xffffc000);
238 	if (ctlr->ich_version == 7) {
239 		struct ich7_spi_regs *ich7_spi;
240 
241 		ich7_spi = (struct ich7_spi_regs *)(rcrb + 0x3020);
242 		ctlr->ichspi_lock = ich_readw(&ich7_spi->spis) & SPIS_LOCK;
243 		ctlr->opmenu = ich7_spi->opmenu;
244 		ctlr->menubytes = sizeof(ich7_spi->opmenu);
245 		ctlr->optype = &ich7_spi->optype;
246 		ctlr->addr = &ich7_spi->spia;
247 		ctlr->data = (uint8_t *)ich7_spi->spid;
248 		ctlr->databytes = sizeof(ich7_spi->spid);
249 		ctlr->status = (uint8_t *)&ich7_spi->spis;
250 		ctlr->control = &ich7_spi->spic;
251 		ctlr->bbar = &ich7_spi->bbar;
252 		ctlr->preop = &ich7_spi->preop;
253 		ctlr->base = ich7_spi;
254 	} else if (ctlr->ich_version == 9) {
255 		struct ich9_spi_regs *ich9_spi;
256 
257 		ich9_spi = (struct ich9_spi_regs *)(rcrb + 0x3800);
258 		ctlr->ichspi_lock = ich_readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
259 		ctlr->opmenu = ich9_spi->opmenu;
260 		ctlr->menubytes = sizeof(ich9_spi->opmenu);
261 		ctlr->optype = &ich9_spi->optype;
262 		ctlr->addr = &ich9_spi->faddr;
263 		ctlr->data = (uint8_t *)ich9_spi->fdata;
264 		ctlr->databytes = sizeof(ich9_spi->fdata);
265 		ctlr->status = &ich9_spi->ssfs;
266 		ctlr->control = (uint16_t *)ich9_spi->ssfc;
267 		ctlr->speed = ich9_spi->ssfc + 2;
268 		ctlr->bbar = &ich9_spi->bbar;
269 		ctlr->preop = &ich9_spi->preop;
270 		ctlr->pr = &ich9_spi->pr[0];
271 		ctlr->base = ich9_spi;
272 	} else {
273 		debug("ICH SPI: Unrecognized ICH version %d.\n",
274 		      ctlr->ich_version);
275 		return -1;
276 	}
277 	debug("ICH SPI: Version %d detected\n", ctlr->ich_version);
278 
279 	/* Work out the maximum speed we can support */
280 	ctlr->max_speed = 20000000;
281 	if (ctlr->ich_version == 9 && ich9_can_do_33mhz(ctlr->dev))
282 		ctlr->max_speed = 33000000;
283 
284 	ich_set_bbar(ctlr, 0);
285 
286 	return 0;
287 }
288 
289 void spi_init(void)
290 {
291 	uint8_t bios_cntl;
292 
293 	if (ich_find_spi_controller(&ctlr.dev, &ctlr.ich_version)) {
294 		printf("ICH SPI: Cannot find device\n");
295 		return;
296 	}
297 
298 	if (ich_init_controller(&ctlr)) {
299 		printf("ICH SPI: Cannot setup controller\n");
300 		return;
301 	}
302 
303 	/*
304 	 * Disable the BIOS write protect so write commands are allowed.  On
305 	 * v9, deassert SMM BIOS Write Protect Disable.
306 	 */
307 	pci_read_config_byte(ctlr.dev, 0xdc, &bios_cntl);
308 	if (ctlr.ich_version == 9)
309 		bios_cntl &= ~(1 << 5);
310 	pci_write_config_byte(ctlr.dev, 0xdc, bios_cntl | 0x1);
311 }
312 
313 int spi_claim_bus(struct spi_slave *slave)
314 {
315 	/* Handled by ICH automatically. */
316 	return 0;
317 }
318 
319 void spi_release_bus(struct spi_slave *slave)
320 {
321 	/* Handled by ICH automatically. */
322 }
323 
324 void spi_cs_activate(struct spi_slave *slave)
325 {
326 	/* Handled by ICH automatically. */
327 }
328 
329 void spi_cs_deactivate(struct spi_slave *slave)
330 {
331 	/* Handled by ICH automatically. */
332 }
333 
334 static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
335 {
336 	trans->out += bytes;
337 	trans->bytesout -= bytes;
338 }
339 
340 static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
341 {
342 	trans->in += bytes;
343 	trans->bytesin -= bytes;
344 }
345 
346 static void spi_setup_type(struct spi_trans *trans, int data_bytes)
347 {
348 	trans->type = 0xFF;
349 
350 	/* Try to guess spi type from read/write sizes. */
351 	if (trans->bytesin == 0) {
352 		if (trans->bytesout + data_bytes > 4)
353 			/*
354 			 * If bytesin = 0 and bytesout > 4, we presume this is
355 			 * a write data operation, which is accompanied by an
356 			 * address.
357 			 */
358 			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
359 		else
360 			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
361 		return;
362 	}
363 
364 	if (trans->bytesout == 1) {	/* and bytesin is > 0 */
365 		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
366 		return;
367 	}
368 
369 	if (trans->bytesout == 4)	/* and bytesin is > 0 */
370 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
371 
372 	/* Fast read command is called with 5 bytes instead of 4 */
373 	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
374 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
375 		--trans->bytesout;
376 	}
377 }
378 
379 static int spi_setup_opcode(struct spi_trans *trans)
380 {
381 	uint16_t optypes;
382 	uint8_t opmenu[ctlr.menubytes];
383 
384 	trans->opcode = trans->out[0];
385 	spi_use_out(trans, 1);
386 	if (!ctlr.ichspi_lock) {
387 		/* The lock is off, so just use index 0. */
388 		ich_writeb(trans->opcode, ctlr.opmenu);
389 		optypes = ich_readw(ctlr.optype);
390 		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
391 		ich_writew(optypes, ctlr.optype);
392 		return 0;
393 	} else {
394 		/* The lock is on. See if what we need is on the menu. */
395 		uint8_t optype;
396 		uint16_t opcode_index;
397 
398 		/* Write Enable is handled as atomic prefix */
399 		if (trans->opcode == SPI_OPCODE_WREN)
400 			return 0;
401 
402 		read_reg(ctlr.opmenu, opmenu, sizeof(opmenu));
403 		for (opcode_index = 0; opcode_index < ctlr.menubytes;
404 				opcode_index++) {
405 			if (opmenu[opcode_index] == trans->opcode)
406 				break;
407 		}
408 
409 		if (opcode_index == ctlr.menubytes) {
410 			printf("ICH SPI: Opcode %x not found\n",
411 			       trans->opcode);
412 			return -1;
413 		}
414 
415 		optypes = ich_readw(ctlr.optype);
416 		optype = (optypes >> (opcode_index * 2)) & 0x3;
417 		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
418 		    optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
419 		    trans->bytesout >= 3) {
420 			/* We guessed wrong earlier. Fix it up. */
421 			trans->type = optype;
422 		}
423 		if (optype != trans->type) {
424 			printf("ICH SPI: Transaction doesn't fit type %d\n",
425 			       optype);
426 			return -1;
427 		}
428 		return opcode_index;
429 	}
430 }
431 
432 static int spi_setup_offset(struct spi_trans *trans)
433 {
434 	/* Separate the SPI address and data. */
435 	switch (trans->type) {
436 	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
437 	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
438 		return 0;
439 	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
440 	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
441 		trans->offset = ((uint32_t)trans->out[0] << 16) |
442 				((uint32_t)trans->out[1] << 8) |
443 				((uint32_t)trans->out[2] << 0);
444 		spi_use_out(trans, 3);
445 		return 1;
446 	default:
447 		printf("Unrecognized SPI transaction type %#x\n", trans->type);
448 		return -1;
449 	}
450 }
451 
452 /*
453  * Wait for up to 6s til status register bit(s) turn 1 (in case wait_til_set
454  * below is true) or 0. In case the wait was for the bit(s) to set - write
455  * those bits back, which would cause resetting them.
456  *
457  * Return the last read status value on success or -1 on failure.
458  */
459 static int ich_status_poll(u16 bitmask, int wait_til_set)
460 {
461 	int timeout = 600000; /* This will result in 6s */
462 	u16 status = 0;
463 
464 	while (timeout--) {
465 		status = ich_readw(ctlr.status);
466 		if (wait_til_set ^ ((status & bitmask) == 0)) {
467 			if (wait_til_set)
468 				ich_writew((status & bitmask), ctlr.status);
469 			return status;
470 		}
471 		udelay(10);
472 	}
473 
474 	printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
475 	       status, bitmask);
476 	return -1;
477 }
478 
479 /*
480 int spi_xfer(struct spi_slave *slave, const void *dout,
481 		unsigned int bitsout, void *din, unsigned int bitsin)
482 */
483 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
484 		void *din, unsigned long flags)
485 {
486 	struct ich_spi_slave *ich = to_ich_spi(slave);
487 	uint16_t control;
488 	int16_t opcode_index;
489 	int with_address;
490 	int status;
491 	int bytes = bitlen / 8;
492 	struct spi_trans *trans = &ich->trans;
493 	unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
494 	int using_cmd = 0;
495 
496 	/* Ee don't support writing partial bytes. */
497 	if (bitlen % 8) {
498 		debug("ICH SPI: Accessing partial bytes not supported\n");
499 		return -1;
500 	}
501 
502 	/* An empty end transaction can be ignored */
503 	if (type == SPI_XFER_END && !dout && !din)
504 		return 0;
505 
506 	if (type & SPI_XFER_BEGIN)
507 		memset(trans, '\0', sizeof(*trans));
508 
509 	/* Dp we need to come back later to finish it? */
510 	if (dout && type == SPI_XFER_BEGIN) {
511 		if (bytes > ICH_MAX_CMD_LEN) {
512 			debug("ICH SPI: Command length limit exceeded\n");
513 			return -1;
514 		}
515 		memcpy(trans->cmd, dout, bytes);
516 		trans->cmd_len = bytes;
517 		debug("ICH SPI: Saved %d bytes\n", bytes);
518 		return 0;
519 	}
520 
521 	/*
522 	 * We process a 'middle' spi_xfer() call, which has no
523 	 * SPI_XFER_BEGIN/END, as an independent transaction as if it had
524 	 * an end. We therefore repeat the command. This is because ICH
525 	 * seems to have no support for this, or because interest (in digging
526 	 * out the details and creating a special case in the code) is low.
527 	 */
528 	if (trans->cmd_len) {
529 		trans->out = trans->cmd;
530 		trans->bytesout = trans->cmd_len;
531 		using_cmd = 1;
532 		debug("ICH SPI: Using %d bytes\n", trans->cmd_len);
533 	} else {
534 		trans->out = dout;
535 		trans->bytesout = dout ? bytes : 0;
536 	}
537 
538 	trans->in = din;
539 	trans->bytesin = din ? bytes : 0;
540 
541 	/* There has to always at least be an opcode. */
542 	if (!trans->bytesout) {
543 		debug("ICH SPI: No opcode for transfer\n");
544 		return -1;
545 	}
546 
547 	if (ich_status_poll(SPIS_SCIP, 0) == -1)
548 		return -1;
549 
550 	ich_writew(SPIS_CDS | SPIS_FCERR, ctlr.status);
551 
552 	spi_setup_type(trans, using_cmd ? bytes : 0);
553 	opcode_index = spi_setup_opcode(trans);
554 	if (opcode_index < 0)
555 		return -1;
556 	with_address = spi_setup_offset(trans);
557 	if (with_address < 0)
558 		return -1;
559 
560 	if (trans->opcode == SPI_OPCODE_WREN) {
561 		/*
562 		 * Treat Write Enable as Atomic Pre-Op if possible
563 		 * in order to prevent the Management Engine from
564 		 * issuing a transaction between WREN and DATA.
565 		 */
566 		if (!ctlr.ichspi_lock)
567 			ich_writew(trans->opcode, ctlr.preop);
568 		return 0;
569 	}
570 
571 	if (ctlr.speed && ctlr.max_speed >= 33000000) {
572 		int byte;
573 
574 		byte = ich_readb(ctlr.speed);
575 		if (ich->speed >= 33000000)
576 			byte |= SSFC_SCF_33MHZ;
577 		else
578 			byte &= ~SSFC_SCF_33MHZ;
579 		ich_writeb(byte, ctlr.speed);
580 	}
581 
582 	/* See if we have used up the command data */
583 	if (using_cmd && dout && bytes) {
584 		trans->out = dout;
585 		trans->bytesout = bytes;
586 		debug("ICH SPI: Moving to data, %d bytes\n", bytes);
587 	}
588 
589 	/* Preset control fields */
590 	control = ich_readw(ctlr.control);
591 	control &= ~SSFC_RESERVED;
592 	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
593 
594 	/* Issue atomic preop cycle if needed */
595 	if (ich_readw(ctlr.preop))
596 		control |= SPIC_ACS;
597 
598 	if (!trans->bytesout && !trans->bytesin) {
599 		/* SPI addresses are 24 bit only */
600 		if (with_address)
601 			ich_writel(trans->offset & 0x00FFFFFF, ctlr.addr);
602 
603 		/*
604 		 * This is a 'no data' command (like Write Enable), its
605 		 * bitesout size was 1, decremented to zero while executing
606 		 * spi_setup_opcode() above. Tell the chip to send the
607 		 * command.
608 		 */
609 		ich_writew(control, ctlr.control);
610 
611 		/* wait for the result */
612 		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
613 		if (status == -1)
614 			return -1;
615 
616 		if (status & SPIS_FCERR) {
617 			debug("ICH SPI: Command transaction error\n");
618 			return -1;
619 		}
620 
621 		return 0;
622 	}
623 
624 	/*
625 	 * Check if this is a write command atempting to transfer more bytes
626 	 * than the controller can handle. Iterations for writes are not
627 	 * supported here because each SPI write command needs to be preceded
628 	 * and followed by other SPI commands, and this sequence is controlled
629 	 * by the SPI chip driver.
630 	 */
631 	if (trans->bytesout > ctlr.databytes) {
632 		debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
633 		return -1;
634 	}
635 
636 	/*
637 	 * Read or write up to databytes bytes at a time until everything has
638 	 * been sent.
639 	 */
640 	while (trans->bytesout || trans->bytesin) {
641 		uint32_t data_length;
642 
643 		/* SPI addresses are 24 bit only */
644 		ich_writel(trans->offset & 0x00FFFFFF, ctlr.addr);
645 
646 		if (trans->bytesout)
647 			data_length = min(trans->bytesout, ctlr.databytes);
648 		else
649 			data_length = min(trans->bytesin, ctlr.databytes);
650 
651 		/* Program data into FDATA0 to N */
652 		if (trans->bytesout) {
653 			write_reg(trans->out, ctlr.data, data_length);
654 			spi_use_out(trans, data_length);
655 			if (with_address)
656 				trans->offset += data_length;
657 		}
658 
659 		/* Add proper control fields' values */
660 		control &= ~((ctlr.databytes - 1) << 8);
661 		control |= SPIC_DS;
662 		control |= (data_length - 1) << 8;
663 
664 		/* write it */
665 		ich_writew(control, ctlr.control);
666 
667 		/* Wait for Cycle Done Status or Flash Cycle Error. */
668 		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
669 		if (status == -1)
670 			return -1;
671 
672 		if (status & SPIS_FCERR) {
673 			debug("ICH SPI: Data transaction error\n");
674 			return -1;
675 		}
676 
677 		if (trans->bytesin) {
678 			read_reg(ctlr.data, trans->in, data_length);
679 			spi_use_in(trans, data_length);
680 			if (with_address)
681 				trans->offset += data_length;
682 		}
683 	}
684 
685 	/* Clear atomic preop now that xfer is done */
686 	ich_writew(0, ctlr.preop);
687 
688 	return 0;
689 }
690 
691 
692 /*
693  * This uses the SPI controller from the Intel Cougar Point and Panther Point
694  * PCH to write-protect portions of the SPI flash until reboot. The changes
695  * don't actually take effect until the HSFS[FLOCKDN] bit is set, but that's
696  * done elsewhere.
697  */
698 int spi_write_protect_region(uint32_t lower_limit, uint32_t length, int hint)
699 {
700 	uint32_t tmplong;
701 	uint32_t upper_limit;
702 
703 	if (!ctlr.pr) {
704 		printf("%s: operation not supported on this chipset\n",
705 		       __func__);
706 		return -1;
707 	}
708 
709 	if (length == 0 ||
710 	    lower_limit > (0xFFFFFFFFUL - length) + 1 ||
711 	    hint < 0 || hint > 4) {
712 		printf("%s(0x%x, 0x%x, %d): invalid args\n", __func__,
713 		       lower_limit, length, hint);
714 		return -1;
715 	}
716 
717 	upper_limit = lower_limit + length - 1;
718 
719 	/*
720 	 * Determine bits to write, as follows:
721 	 *  31     Write-protection enable (includes erase operation)
722 	 *  30:29  reserved
723 	 *  28:16  Upper Limit (FLA address bits 24:12, with 11:0 == 0xfff)
724 	 *  15     Read-protection enable
725 	 *  14:13  reserved
726 	 *  12:0   Lower Limit (FLA address bits 24:12, with 11:0 == 0x000)
727 	 */
728 	tmplong = 0x80000000 |
729 		((upper_limit & 0x01fff000) << 4) |
730 		((lower_limit & 0x01fff000) >> 12);
731 
732 	printf("%s: writing 0x%08x to %p\n", __func__, tmplong,
733 	       &ctlr.pr[hint]);
734 	ctlr.pr[hint] = tmplong;
735 
736 	return 0;
737 }
738