xref: /openbmc/u-boot/drivers/spi/ich.c (revision 32df39c7)
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 <errno.h>
11 #include <malloc.h>
12 #include <spi.h>
13 #include <pci.h>
14 #include <pci_ids.h>
15 #include <asm/io.h>
16 
17 #include "ich.h"
18 
19 #define SPI_OPCODE_WREN      0x06
20 #define SPI_OPCODE_FAST_READ 0x0b
21 
22 struct ich_ctlr {
23 	pci_dev_t dev;		/* PCI device number */
24 	int ich_version;	/* Controller version, 7 or 9 */
25 	bool use_sbase;		/* Use SBASE instead of RCB */
26 	int ichspi_lock;
27 	int locked;
28 	uint8_t *opmenu;
29 	int menubytes;
30 	void *base;		/* Base of register set */
31 	uint16_t *preop;
32 	uint16_t *optype;
33 	uint32_t *addr;
34 	uint8_t *data;
35 	unsigned databytes;
36 	uint8_t *status;
37 	uint16_t *control;
38 	uint32_t *bbar;
39 	uint32_t *pr;		/* only for ich9 */
40 	uint8_t *speed;		/* pointer to speed control */
41 	ulong max_speed;	/* Maximum bus speed in MHz */
42 };
43 
44 struct ich_ctlr ctlr;
45 
46 static inline struct ich_spi_slave *to_ich_spi(struct spi_slave *slave)
47 {
48 	return container_of(slave, struct ich_spi_slave, slave);
49 }
50 
51 static unsigned int ich_reg(const void *addr)
52 {
53 	return (unsigned)(addr - ctlr.base) & 0xffff;
54 }
55 
56 static u8 ich_readb(const void *addr)
57 {
58 	u8 value = readb(addr);
59 
60 	debug("read %2.2x from %4.4x\n", value, ich_reg(addr));
61 
62 	return value;
63 }
64 
65 static u16 ich_readw(const void *addr)
66 {
67 	u16 value = readw(addr);
68 
69 	debug("read %4.4x from %4.4x\n", value, ich_reg(addr));
70 
71 	return value;
72 }
73 
74 static u32 ich_readl(const void *addr)
75 {
76 	u32 value = readl(addr);
77 
78 	debug("read %8.8x from %4.4x\n", value, ich_reg(addr));
79 
80 	return value;
81 }
82 
83 static void ich_writeb(u8 value, void *addr)
84 {
85 	writeb(value, addr);
86 	debug("wrote %2.2x to %4.4x\n", value, ich_reg(addr));
87 }
88 
89 static void ich_writew(u16 value, void *addr)
90 {
91 	writew(value, addr);
92 	debug("wrote %4.4x to %4.4x\n", value, ich_reg(addr));
93 }
94 
95 static void ich_writel(u32 value, void *addr)
96 {
97 	writel(value, addr);
98 	debug("wrote %8.8x to %4.4x\n", value, ich_reg(addr));
99 }
100 
101 static void write_reg(const void *value, void *dest, uint32_t size)
102 {
103 	memcpy_toio(dest, value, size);
104 }
105 
106 static void read_reg(const void *src, void *value, uint32_t size)
107 {
108 	memcpy_fromio(value, src, size);
109 }
110 
111 static void ich_set_bbar(struct ich_ctlr *ctlr, uint32_t minaddr)
112 {
113 	const uint32_t bbar_mask = 0x00ffff00;
114 	uint32_t ichspi_bbar;
115 
116 	minaddr &= bbar_mask;
117 	ichspi_bbar = ich_readl(ctlr->bbar) & ~bbar_mask;
118 	ichspi_bbar |= minaddr;
119 	ich_writel(ichspi_bbar, ctlr->bbar);
120 }
121 
122 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
123 {
124 	puts("spi_cs_is_valid used but not implemented\n");
125 	return 0;
126 }
127 
128 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
129 		unsigned int max_hz, unsigned int mode)
130 {
131 	struct ich_spi_slave *ich;
132 
133 	ich = spi_alloc_slave(struct ich_spi_slave, bus, cs);
134 	if (!ich) {
135 		puts("ICH SPI: Out of memory\n");
136 		return NULL;
137 	}
138 
139 	/*
140 	 * Yes this controller can only write a small number of bytes at
141 	 * once! The limit is typically 64 bytes.
142 	 */
143 	ich->slave.max_write_size = ctlr.databytes;
144 	ich->speed = max_hz;
145 
146 	/*
147 	 * ICH 7 SPI controller only supports array read command
148 	 * and byte program command for SST flash
149 	 */
150 	if (ctlr.ich_version == 7 || ctlr.use_sbase) {
151 		ich->slave.op_mode_rx = SPI_OPM_RX_AS;
152 		ich->slave.op_mode_tx = SPI_OPM_TX_BP;
153 	}
154 
155 	return &ich->slave;
156 }
157 
158 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node,
159 				      int spi_node)
160 {
161 	/* We only support a single SPI at present */
162 	return spi_setup_slave(0, 0, 20000000, 0);
163 }
164 
165 void spi_free_slave(struct spi_slave *slave)
166 {
167 	struct ich_spi_slave *ich = to_ich_spi(slave);
168 
169 	free(ich);
170 }
171 
172 /*
173  * Check if this device ID matches one of supported Intel PCH devices.
174  *
175  * Return the ICH version if there is a match, or zero otherwise.
176  */
177 static int get_ich_version(uint16_t device_id)
178 {
179 	if (device_id == PCI_DEVICE_ID_INTEL_TGP_LPC ||
180 	    device_id == PCI_DEVICE_ID_INTEL_ITC_LPC ||
181 	    device_id == PCI_DEVICE_ID_INTEL_QRK_ILB)
182 		return 7;
183 
184 	if ((device_id >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
185 	     device_id <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX) ||
186 	    (device_id >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
187 	     device_id <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX) ||
188 	    device_id == PCI_DEVICE_ID_INTEL_VALLEYVIEW_LPC)
189 		return 9;
190 
191 	return 0;
192 }
193 
194 /* @return 1 if the SPI flash supports the 33MHz speed */
195 static int ich9_can_do_33mhz(pci_dev_t dev)
196 {
197 	u32 fdod, speed;
198 
199 	/* Observe SPI Descriptor Component Section 0 */
200 	pci_write_config_dword(dev, 0xb0, 0x1000);
201 
202 	/* Extract the Write/Erase SPI Frequency from descriptor */
203 	pci_read_config_dword(dev, 0xb4, &fdod);
204 
205 	/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
206 	speed = (fdod >> 21) & 7;
207 
208 	return speed == 1;
209 }
210 
211 static int ich_find_spi_controller(struct ich_ctlr *ich)
212 {
213 	int last_bus = pci_last_busno();
214 	int bus;
215 
216 	if (last_bus == -1) {
217 		debug("No PCI busses?\n");
218 		return -ENODEV;
219 	}
220 
221 	for (bus = 0; bus <= last_bus; bus++) {
222 		uint16_t vendor_id, device_id;
223 		uint32_t ids;
224 		pci_dev_t dev;
225 
226 		dev = PCI_BDF(bus, 31, 0);
227 		pci_read_config_dword(dev, 0, &ids);
228 		vendor_id = ids;
229 		device_id = ids >> 16;
230 
231 		if (vendor_id == PCI_VENDOR_ID_INTEL) {
232 			ich->dev = dev;
233 			ich->ich_version = get_ich_version(device_id);
234 			if (device_id == PCI_DEVICE_ID_INTEL_VALLEYVIEW_LPC)
235 				ich->use_sbase = true;
236 			return ich->ich_version == 0 ? -ENODEV : 0;
237 		}
238 	}
239 
240 	debug("ICH SPI: No ICH found.\n");
241 	return -ENODEV;
242 }
243 
244 static int ich_init_controller(struct ich_ctlr *ctlr)
245 {
246 	uint8_t *rcrb; /* Root Complex Register Block */
247 	uint32_t rcba; /* Root Complex Base Address */
248 	uint32_t sbase_addr;
249 	uint8_t *sbase;
250 
251 	pci_read_config_dword(ctlr->dev, 0xf0, &rcba);
252 	/* Bits 31-14 are the base address, 13-1 are reserved, 0 is enable. */
253 	rcrb = (uint8_t *)(rcba & 0xffffc000);
254 
255 	/* SBASE is similar */
256 	pci_read_config_dword(ctlr->dev, 0x54, &sbase_addr);
257 	sbase = (uint8_t *)(sbase_addr & 0xfffffe00);
258 
259 	if (ctlr->ich_version == 7) {
260 		struct ich7_spi_regs *ich7_spi;
261 
262 		ich7_spi = (struct ich7_spi_regs *)(rcrb + 0x3020);
263 		ctlr->ichspi_lock = ich_readw(&ich7_spi->spis) & SPIS_LOCK;
264 		ctlr->opmenu = ich7_spi->opmenu;
265 		ctlr->menubytes = sizeof(ich7_spi->opmenu);
266 		ctlr->optype = &ich7_spi->optype;
267 		ctlr->addr = &ich7_spi->spia;
268 		ctlr->data = (uint8_t *)ich7_spi->spid;
269 		ctlr->databytes = sizeof(ich7_spi->spid);
270 		ctlr->status = (uint8_t *)&ich7_spi->spis;
271 		ctlr->control = &ich7_spi->spic;
272 		ctlr->bbar = &ich7_spi->bbar;
273 		ctlr->preop = &ich7_spi->preop;
274 		ctlr->base = ich7_spi;
275 	} else if (ctlr->ich_version == 9) {
276 		struct ich9_spi_regs *ich9_spi;
277 
278 		if (ctlr->use_sbase)
279 			ich9_spi = (struct ich9_spi_regs *)sbase;
280 		else
281 			ich9_spi = (struct ich9_spi_regs *)(rcrb + 0x3800);
282 		ctlr->ichspi_lock = ich_readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
283 		ctlr->opmenu = ich9_spi->opmenu;
284 		ctlr->menubytes = sizeof(ich9_spi->opmenu);
285 		ctlr->optype = &ich9_spi->optype;
286 		ctlr->addr = &ich9_spi->faddr;
287 		ctlr->data = (uint8_t *)ich9_spi->fdata;
288 		ctlr->databytes = sizeof(ich9_spi->fdata);
289 		ctlr->status = &ich9_spi->ssfs;
290 		ctlr->control = (uint16_t *)ich9_spi->ssfc;
291 		ctlr->speed = ich9_spi->ssfc + 2;
292 		ctlr->bbar = &ich9_spi->bbar;
293 		ctlr->preop = &ich9_spi->preop;
294 		ctlr->pr = &ich9_spi->pr[0];
295 		ctlr->base = ich9_spi;
296 	} else {
297 		debug("ICH SPI: Unrecognized ICH version %d.\n",
298 		      ctlr->ich_version);
299 		return -1;
300 	}
301 
302 	/* Work out the maximum speed we can support */
303 	ctlr->max_speed = 20000000;
304 	if (ctlr->ich_version == 9 && ich9_can_do_33mhz(ctlr->dev))
305 		ctlr->max_speed = 33000000;
306 	debug("ICH SPI: Version %d detected at %p, speed %ld\n",
307 	      ctlr->ich_version, ctlr->base, ctlr->max_speed);
308 
309 	ich_set_bbar(ctlr, 0);
310 
311 	return 0;
312 }
313 
314 void spi_init(void)
315 {
316 	uint8_t bios_cntl;
317 
318 	if (ich_find_spi_controller(&ctlr)) {
319 		printf("ICH SPI: Cannot find device\n");
320 		return;
321 	}
322 
323 	if (ich_init_controller(&ctlr)) {
324 		printf("ICH SPI: Cannot setup controller\n");
325 		return;
326 	}
327 
328 	/*
329 	 * Disable the BIOS write protect so write commands are allowed.  On
330 	 * v9, deassert SMM BIOS Write Protect Disable.
331 	 */
332 	if (ctlr.use_sbase) {
333 		struct ich9_spi_regs *ich9_spi;
334 
335 		ich9_spi = (struct ich9_spi_regs *)ctlr.base;
336 		bios_cntl = ich_readb(&ich9_spi->bcr);
337 		bios_cntl &= ~(1 << 5);	/* clear Enable InSMM_STS (EISS) */
338 		bios_cntl |= 1;		/* Write Protect Disable (WPD) */
339 		ich_writeb(bios_cntl, &ich9_spi->bcr);
340 	} else {
341 		pci_read_config_byte(ctlr.dev, 0xdc, &bios_cntl);
342 		if (ctlr.ich_version == 9)
343 			bios_cntl &= ~(1 << 5);
344 		pci_write_config_byte(ctlr.dev, 0xdc, bios_cntl | 0x1);
345 	}
346 }
347 
348 int spi_claim_bus(struct spi_slave *slave)
349 {
350 	/* Handled by ICH automatically. */
351 	return 0;
352 }
353 
354 void spi_release_bus(struct spi_slave *slave)
355 {
356 	/* Handled by ICH automatically. */
357 }
358 
359 void spi_cs_activate(struct spi_slave *slave)
360 {
361 	/* Handled by ICH automatically. */
362 }
363 
364 void spi_cs_deactivate(struct spi_slave *slave)
365 {
366 	/* Handled by ICH automatically. */
367 }
368 
369 static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
370 {
371 	trans->out += bytes;
372 	trans->bytesout -= bytes;
373 }
374 
375 static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
376 {
377 	trans->in += bytes;
378 	trans->bytesin -= bytes;
379 }
380 
381 static void spi_setup_type(struct spi_trans *trans, int data_bytes)
382 {
383 	trans->type = 0xFF;
384 
385 	/* Try to guess spi type from read/write sizes. */
386 	if (trans->bytesin == 0) {
387 		if (trans->bytesout + data_bytes > 4)
388 			/*
389 			 * If bytesin = 0 and bytesout > 4, we presume this is
390 			 * a write data operation, which is accompanied by an
391 			 * address.
392 			 */
393 			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
394 		else
395 			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
396 		return;
397 	}
398 
399 	if (trans->bytesout == 1) {	/* and bytesin is > 0 */
400 		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
401 		return;
402 	}
403 
404 	if (trans->bytesout == 4)	/* and bytesin is > 0 */
405 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
406 
407 	/* Fast read command is called with 5 bytes instead of 4 */
408 	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
409 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
410 		--trans->bytesout;
411 	}
412 }
413 
414 static int spi_setup_opcode(struct spi_trans *trans)
415 {
416 	uint16_t optypes;
417 	uint8_t opmenu[ctlr.menubytes];
418 
419 	trans->opcode = trans->out[0];
420 	spi_use_out(trans, 1);
421 	if (!ctlr.ichspi_lock) {
422 		/* The lock is off, so just use index 0. */
423 		ich_writeb(trans->opcode, ctlr.opmenu);
424 		optypes = ich_readw(ctlr.optype);
425 		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
426 		ich_writew(optypes, ctlr.optype);
427 		return 0;
428 	} else {
429 		/* The lock is on. See if what we need is on the menu. */
430 		uint8_t optype;
431 		uint16_t opcode_index;
432 
433 		/* Write Enable is handled as atomic prefix */
434 		if (trans->opcode == SPI_OPCODE_WREN)
435 			return 0;
436 
437 		read_reg(ctlr.opmenu, opmenu, sizeof(opmenu));
438 		for (opcode_index = 0; opcode_index < ctlr.menubytes;
439 				opcode_index++) {
440 			if (opmenu[opcode_index] == trans->opcode)
441 				break;
442 		}
443 
444 		if (opcode_index == ctlr.menubytes) {
445 			printf("ICH SPI: Opcode %x not found\n",
446 			       trans->opcode);
447 			return -1;
448 		}
449 
450 		optypes = ich_readw(ctlr.optype);
451 		optype = (optypes >> (opcode_index * 2)) & 0x3;
452 		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
453 		    optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
454 		    trans->bytesout >= 3) {
455 			/* We guessed wrong earlier. Fix it up. */
456 			trans->type = optype;
457 		}
458 		if (optype != trans->type) {
459 			printf("ICH SPI: Transaction doesn't fit type %d\n",
460 			       optype);
461 			return -1;
462 		}
463 		return opcode_index;
464 	}
465 }
466 
467 static int spi_setup_offset(struct spi_trans *trans)
468 {
469 	/* Separate the SPI address and data. */
470 	switch (trans->type) {
471 	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
472 	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
473 		return 0;
474 	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
475 	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
476 		trans->offset = ((uint32_t)trans->out[0] << 16) |
477 				((uint32_t)trans->out[1] << 8) |
478 				((uint32_t)trans->out[2] << 0);
479 		spi_use_out(trans, 3);
480 		return 1;
481 	default:
482 		printf("Unrecognized SPI transaction type %#x\n", trans->type);
483 		return -1;
484 	}
485 }
486 
487 /*
488  * Wait for up to 6s til status register bit(s) turn 1 (in case wait_til_set
489  * below is true) or 0. In case the wait was for the bit(s) to set - write
490  * those bits back, which would cause resetting them.
491  *
492  * Return the last read status value on success or -1 on failure.
493  */
494 static int ich_status_poll(u16 bitmask, int wait_til_set)
495 {
496 	int timeout = 600000; /* This will result in 6s */
497 	u16 status = 0;
498 
499 	while (timeout--) {
500 		status = ich_readw(ctlr.status);
501 		if (wait_til_set ^ ((status & bitmask) == 0)) {
502 			if (wait_til_set)
503 				ich_writew((status & bitmask), ctlr.status);
504 			return status;
505 		}
506 		udelay(10);
507 	}
508 
509 	printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
510 	       status, bitmask);
511 	return -1;
512 }
513 
514 /*
515 int spi_xfer(struct spi_slave *slave, const void *dout,
516 		unsigned int bitsout, void *din, unsigned int bitsin)
517 */
518 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
519 		void *din, unsigned long flags)
520 {
521 	struct ich_spi_slave *ich = to_ich_spi(slave);
522 	uint16_t control;
523 	int16_t opcode_index;
524 	int with_address;
525 	int status;
526 	int bytes = bitlen / 8;
527 	struct spi_trans *trans = &ich->trans;
528 	unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
529 	int using_cmd = 0;
530 
531 	/* Ee don't support writing partial bytes. */
532 	if (bitlen % 8) {
533 		debug("ICH SPI: Accessing partial bytes not supported\n");
534 		return -1;
535 	}
536 
537 	/* An empty end transaction can be ignored */
538 	if (type == SPI_XFER_END && !dout && !din)
539 		return 0;
540 
541 	if (type & SPI_XFER_BEGIN)
542 		memset(trans, '\0', sizeof(*trans));
543 
544 	/* Dp we need to come back later to finish it? */
545 	if (dout && type == SPI_XFER_BEGIN) {
546 		if (bytes > ICH_MAX_CMD_LEN) {
547 			debug("ICH SPI: Command length limit exceeded\n");
548 			return -1;
549 		}
550 		memcpy(trans->cmd, dout, bytes);
551 		trans->cmd_len = bytes;
552 		debug("ICH SPI: Saved %d bytes\n", bytes);
553 		return 0;
554 	}
555 
556 	/*
557 	 * We process a 'middle' spi_xfer() call, which has no
558 	 * SPI_XFER_BEGIN/END, as an independent transaction as if it had
559 	 * an end. We therefore repeat the command. This is because ICH
560 	 * seems to have no support for this, or because interest (in digging
561 	 * out the details and creating a special case in the code) is low.
562 	 */
563 	if (trans->cmd_len) {
564 		trans->out = trans->cmd;
565 		trans->bytesout = trans->cmd_len;
566 		using_cmd = 1;
567 		debug("ICH SPI: Using %d bytes\n", trans->cmd_len);
568 	} else {
569 		trans->out = dout;
570 		trans->bytesout = dout ? bytes : 0;
571 	}
572 
573 	trans->in = din;
574 	trans->bytesin = din ? bytes : 0;
575 
576 	/* There has to always at least be an opcode. */
577 	if (!trans->bytesout) {
578 		debug("ICH SPI: No opcode for transfer\n");
579 		return -1;
580 	}
581 
582 	if (ich_status_poll(SPIS_SCIP, 0) == -1)
583 		return -1;
584 
585 	ich_writew(SPIS_CDS | SPIS_FCERR, ctlr.status);
586 
587 	spi_setup_type(trans, using_cmd ? bytes : 0);
588 	opcode_index = spi_setup_opcode(trans);
589 	if (opcode_index < 0)
590 		return -1;
591 	with_address = spi_setup_offset(trans);
592 	if (with_address < 0)
593 		return -1;
594 
595 	if (trans->opcode == SPI_OPCODE_WREN) {
596 		/*
597 		 * Treat Write Enable as Atomic Pre-Op if possible
598 		 * in order to prevent the Management Engine from
599 		 * issuing a transaction between WREN and DATA.
600 		 */
601 		if (!ctlr.ichspi_lock)
602 			ich_writew(trans->opcode, ctlr.preop);
603 		return 0;
604 	}
605 
606 	if (ctlr.speed && ctlr.max_speed >= 33000000) {
607 		int byte;
608 
609 		byte = ich_readb(ctlr.speed);
610 		if (ich->speed >= 33000000)
611 			byte |= SSFC_SCF_33MHZ;
612 		else
613 			byte &= ~SSFC_SCF_33MHZ;
614 		ich_writeb(byte, ctlr.speed);
615 	}
616 
617 	/* See if we have used up the command data */
618 	if (using_cmd && dout && bytes) {
619 		trans->out = dout;
620 		trans->bytesout = bytes;
621 		debug("ICH SPI: Moving to data, %d bytes\n", bytes);
622 	}
623 
624 	/* Preset control fields */
625 	control = ich_readw(ctlr.control);
626 	control &= ~SSFC_RESERVED;
627 	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
628 
629 	/* Issue atomic preop cycle if needed */
630 	if (ich_readw(ctlr.preop))
631 		control |= SPIC_ACS;
632 
633 	if (!trans->bytesout && !trans->bytesin) {
634 		/* SPI addresses are 24 bit only */
635 		if (with_address)
636 			ich_writel(trans->offset & 0x00FFFFFF, ctlr.addr);
637 
638 		/*
639 		 * This is a 'no data' command (like Write Enable), its
640 		 * bitesout size was 1, decremented to zero while executing
641 		 * spi_setup_opcode() above. Tell the chip to send the
642 		 * command.
643 		 */
644 		ich_writew(control, ctlr.control);
645 
646 		/* wait for the result */
647 		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
648 		if (status == -1)
649 			return -1;
650 
651 		if (status & SPIS_FCERR) {
652 			debug("ICH SPI: Command transaction error\n");
653 			return -1;
654 		}
655 
656 		return 0;
657 	}
658 
659 	/*
660 	 * Check if this is a write command atempting to transfer more bytes
661 	 * than the controller can handle. Iterations for writes are not
662 	 * supported here because each SPI write command needs to be preceded
663 	 * and followed by other SPI commands, and this sequence is controlled
664 	 * by the SPI chip driver.
665 	 */
666 	if (trans->bytesout > ctlr.databytes) {
667 		debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
668 		return -1;
669 	}
670 
671 	/*
672 	 * Read or write up to databytes bytes at a time until everything has
673 	 * been sent.
674 	 */
675 	while (trans->bytesout || trans->bytesin) {
676 		uint32_t data_length;
677 
678 		/* SPI addresses are 24 bit only */
679 		ich_writel(trans->offset & 0x00FFFFFF, ctlr.addr);
680 
681 		if (trans->bytesout)
682 			data_length = min(trans->bytesout, ctlr.databytes);
683 		else
684 			data_length = min(trans->bytesin, ctlr.databytes);
685 
686 		/* Program data into FDATA0 to N */
687 		if (trans->bytesout) {
688 			write_reg(trans->out, ctlr.data, data_length);
689 			spi_use_out(trans, data_length);
690 			if (with_address)
691 				trans->offset += data_length;
692 		}
693 
694 		/* Add proper control fields' values */
695 		control &= ~((ctlr.databytes - 1) << 8);
696 		control |= SPIC_DS;
697 		control |= (data_length - 1) << 8;
698 
699 		/* write it */
700 		ich_writew(control, ctlr.control);
701 
702 		/* Wait for Cycle Done Status or Flash Cycle Error. */
703 		status = ich_status_poll(SPIS_CDS | SPIS_FCERR, 1);
704 		if (status == -1)
705 			return -1;
706 
707 		if (status & SPIS_FCERR) {
708 			debug("ICH SPI: Data transaction error\n");
709 			return -1;
710 		}
711 
712 		if (trans->bytesin) {
713 			read_reg(ctlr.data, trans->in, data_length);
714 			spi_use_in(trans, data_length);
715 			if (with_address)
716 				trans->offset += data_length;
717 		}
718 	}
719 
720 	/* Clear atomic preop now that xfer is done */
721 	ich_writew(0, ctlr.preop);
722 
723 	return 0;
724 }
725 
726 
727 /*
728  * This uses the SPI controller from the Intel Cougar Point and Panther Point
729  * PCH to write-protect portions of the SPI flash until reboot. The changes
730  * don't actually take effect until the HSFS[FLOCKDN] bit is set, but that's
731  * done elsewhere.
732  */
733 int spi_write_protect_region(uint32_t lower_limit, uint32_t length, int hint)
734 {
735 	uint32_t tmplong;
736 	uint32_t upper_limit;
737 
738 	if (!ctlr.pr) {
739 		printf("%s: operation not supported on this chipset\n",
740 		       __func__);
741 		return -1;
742 	}
743 
744 	if (length == 0 ||
745 	    lower_limit > (0xFFFFFFFFUL - length) + 1 ||
746 	    hint < 0 || hint > 4) {
747 		printf("%s(0x%x, 0x%x, %d): invalid args\n", __func__,
748 		       lower_limit, length, hint);
749 		return -1;
750 	}
751 
752 	upper_limit = lower_limit + length - 1;
753 
754 	/*
755 	 * Determine bits to write, as follows:
756 	 *  31     Write-protection enable (includes erase operation)
757 	 *  30:29  reserved
758 	 *  28:16  Upper Limit (FLA address bits 24:12, with 11:0 == 0xfff)
759 	 *  15     Read-protection enable
760 	 *  14:13  reserved
761 	 *  12:0   Lower Limit (FLA address bits 24:12, with 11:0 == 0x000)
762 	 */
763 	tmplong = 0x80000000 |
764 		((upper_limit & 0x01fff000) << 4) |
765 		((lower_limit & 0x01fff000) >> 12);
766 
767 	printf("%s: writing 0x%08x to %p\n", __func__, tmplong,
768 	       &ctlr.pr[hint]);
769 	ctlr.pr[hint] = tmplong;
770 
771 	return 0;
772 }
773