xref: /openbmc/u-boot/drivers/spi/ich.c (revision 58d423b8)
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 <spi.h>
14 #include <pci.h>
15 #include <pci_ids.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 struct ich_spi_platdata {
24 	pci_dev_t dev;		/* PCI device number */
25 	int ich_version;	/* Controller version, 7 or 9 */
26 	bool use_sbase;		/* Use SBASE instead of RCB */
27 };
28 
29 struct ich_spi_priv {
30 	int ichspi_lock;
31 	int locked;
32 	int opmenu;
33 	int menubytes;
34 	void *base;		/* Base of register set */
35 	int preop;
36 	int optype;
37 	int addr;
38 	int data;
39 	unsigned databytes;
40 	int status;
41 	int control;
42 	int bbar;
43 	uint32_t *pr;		/* only for ich9 */
44 	int speed;		/* pointer to speed control */
45 	ulong max_speed;	/* Maximum bus speed in MHz */
46 	ulong cur_speed;	/* Current bus speed */
47 	struct spi_trans trans;	/* current transaction in progress */
48 };
49 
50 static u8 ich_readb(struct ich_spi_priv *priv, int reg)
51 {
52 	u8 value = readb(priv->base + reg);
53 
54 	debug("read %2.2x from %4.4x\n", value, reg);
55 
56 	return value;
57 }
58 
59 static u16 ich_readw(struct ich_spi_priv *priv, int reg)
60 {
61 	u16 value = readw(priv->base + reg);
62 
63 	debug("read %4.4x from %4.4x\n", value, reg);
64 
65 	return value;
66 }
67 
68 static u32 ich_readl(struct ich_spi_priv *priv, int reg)
69 {
70 	u32 value = readl(priv->base + reg);
71 
72 	debug("read %8.8x from %4.4x\n", value, reg);
73 
74 	return value;
75 }
76 
77 static void ich_writeb(struct ich_spi_priv *priv, u8 value, int reg)
78 {
79 	writeb(value, priv->base + reg);
80 	debug("wrote %2.2x to %4.4x\n", value, reg);
81 }
82 
83 static void ich_writew(struct ich_spi_priv *priv, u16 value, int reg)
84 {
85 	writew(value, priv->base + reg);
86 	debug("wrote %4.4x to %4.4x\n", value, reg);
87 }
88 
89 static void ich_writel(struct ich_spi_priv *priv, u32 value, int reg)
90 {
91 	writel(value, priv->base + reg);
92 	debug("wrote %8.8x to %4.4x\n", value, reg);
93 }
94 
95 static void write_reg(struct ich_spi_priv *priv, const void *value,
96 		      int dest_reg, uint32_t size)
97 {
98 	memcpy_toio(priv->base + dest_reg, value, size);
99 }
100 
101 static void read_reg(struct ich_spi_priv *priv, int src_reg, void *value,
102 		     uint32_t size)
103 {
104 	memcpy_fromio(value, priv->base + src_reg, size);
105 }
106 
107 static void ich_set_bbar(struct ich_spi_priv *ctlr, uint32_t minaddr)
108 {
109 	const uint32_t bbar_mask = 0x00ffff00;
110 	uint32_t ichspi_bbar;
111 
112 	minaddr &= bbar_mask;
113 	ichspi_bbar = ich_readl(ctlr, ctlr->bbar) & ~bbar_mask;
114 	ichspi_bbar |= minaddr;
115 	ich_writel(ctlr, ichspi_bbar, ctlr->bbar);
116 }
117 
118 /*
119  * Check if this device ID matches one of supported Intel PCH devices.
120  *
121  * Return the ICH version if there is a match, or zero otherwise.
122  */
123 static int get_ich_version(uint16_t device_id)
124 {
125 	if (device_id == PCI_DEVICE_ID_INTEL_TGP_LPC ||
126 	    device_id == PCI_DEVICE_ID_INTEL_ITC_LPC ||
127 	    device_id == PCI_DEVICE_ID_INTEL_QRK_ILB)
128 		return 7;
129 
130 	if ((device_id >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
131 	     device_id <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX) ||
132 	    (device_id >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
133 	     device_id <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX) ||
134 	    device_id == PCI_DEVICE_ID_INTEL_VALLEYVIEW_LPC ||
135 	    device_id == PCI_DEVICE_ID_INTEL_LYNXPOINT_LPC)
136 		return 9;
137 
138 	return 0;
139 }
140 
141 /* @return 1 if the SPI flash supports the 33MHz speed */
142 static int ich9_can_do_33mhz(pci_dev_t dev)
143 {
144 	u32 fdod, speed;
145 
146 	/* Observe SPI Descriptor Component Section 0 */
147 	pci_write_config_dword(dev, 0xb0, 0x1000);
148 
149 	/* Extract the Write/Erase SPI Frequency from descriptor */
150 	pci_read_config_dword(dev, 0xb4, &fdod);
151 
152 	/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
153 	speed = (fdod >> 21) & 7;
154 
155 	return speed == 1;
156 }
157 
158 static int ich_find_spi_controller(struct ich_spi_platdata *ich)
159 {
160 	int last_bus = pci_last_busno();
161 	int bus;
162 
163 	if (last_bus == -1) {
164 		debug("No PCI busses?\n");
165 		return -ENODEV;
166 	}
167 
168 	for (bus = 0; bus <= last_bus; bus++) {
169 		uint16_t vendor_id, device_id;
170 		uint32_t ids;
171 		pci_dev_t dev;
172 
173 		dev = PCI_BDF(bus, 31, 0);
174 		pci_read_config_dword(dev, 0, &ids);
175 		vendor_id = ids;
176 		device_id = ids >> 16;
177 
178 		if (vendor_id == PCI_VENDOR_ID_INTEL) {
179 			ich->dev = dev;
180 			ich->ich_version = get_ich_version(device_id);
181 			if (device_id == PCI_DEVICE_ID_INTEL_VALLEYVIEW_LPC)
182 				ich->use_sbase = true;
183 			return ich->ich_version == 0 ? -ENODEV : 0;
184 		}
185 	}
186 
187 	debug("ICH SPI: No ICH found.\n");
188 	return -ENODEV;
189 }
190 
191 static int ich_init_controller(struct ich_spi_platdata *plat,
192 			       struct ich_spi_priv *ctlr)
193 {
194 	uint8_t *rcrb; /* Root Complex Register Block */
195 	uint32_t rcba; /* Root Complex Base Address */
196 	uint32_t sbase_addr;
197 	uint8_t *sbase;
198 
199 	pci_read_config_dword(plat->dev, 0xf0, &rcba);
200 	/* Bits 31-14 are the base address, 13-1 are reserved, 0 is enable. */
201 	rcrb = (uint8_t *)(rcba & 0xffffc000);
202 
203 	/* SBASE is similar */
204 	pci_read_config_dword(plat->dev, 0x54, &sbase_addr);
205 	sbase = (uint8_t *)(sbase_addr & 0xfffffe00);
206 
207 	if (plat->ich_version == 7) {
208 		struct ich7_spi_regs *ich7_spi;
209 
210 		ich7_spi = (struct ich7_spi_regs *)(rcrb + 0x3020);
211 		ctlr->ichspi_lock = readw(&ich7_spi->spis) & SPIS_LOCK;
212 		ctlr->opmenu = offsetof(struct ich7_spi_regs, opmenu);
213 		ctlr->menubytes = sizeof(ich7_spi->opmenu);
214 		ctlr->optype = offsetof(struct ich7_spi_regs, optype);
215 		ctlr->addr = offsetof(struct ich7_spi_regs, spia);
216 		ctlr->data = offsetof(struct ich7_spi_regs, spid);
217 		ctlr->databytes = sizeof(ich7_spi->spid);
218 		ctlr->status = offsetof(struct ich7_spi_regs, spis);
219 		ctlr->control = offsetof(struct ich7_spi_regs, spic);
220 		ctlr->bbar = offsetof(struct ich7_spi_regs, bbar);
221 		ctlr->preop = offsetof(struct ich7_spi_regs, preop);
222 		ctlr->base = ich7_spi;
223 	} else if (plat->ich_version == 9) {
224 		struct ich9_spi_regs *ich9_spi;
225 
226 		if (plat->use_sbase)
227 			ich9_spi = (struct ich9_spi_regs *)sbase;
228 		else
229 			ich9_spi = (struct ich9_spi_regs *)(rcrb + 0x3800);
230 		ctlr->ichspi_lock = readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
231 		ctlr->opmenu = offsetof(struct ich9_spi_regs, opmenu);
232 		ctlr->menubytes = sizeof(ich9_spi->opmenu);
233 		ctlr->optype = offsetof(struct ich9_spi_regs, optype);
234 		ctlr->addr = offsetof(struct ich9_spi_regs, faddr);
235 		ctlr->data = offsetof(struct ich9_spi_regs, fdata);
236 		ctlr->databytes = sizeof(ich9_spi->fdata);
237 		ctlr->status = offsetof(struct ich9_spi_regs, ssfs);
238 		ctlr->control = offsetof(struct ich9_spi_regs, ssfc);
239 		ctlr->speed = ctlr->control + 2;
240 		ctlr->bbar = offsetof(struct ich9_spi_regs, bbar);
241 		ctlr->preop = offsetof(struct ich9_spi_regs, preop);
242 		ctlr->pr = &ich9_spi->pr[0];
243 		ctlr->base = ich9_spi;
244 	} else {
245 		debug("ICH SPI: Unrecognised ICH version %d\n",
246 		      plat->ich_version);
247 		return -EINVAL;
248 	}
249 
250 	/* Work out the maximum speed we can support */
251 	ctlr->max_speed = 20000000;
252 	if (plat->ich_version == 9 && ich9_can_do_33mhz(plat->dev))
253 		ctlr->max_speed = 33000000;
254 	debug("ICH SPI: Version %d detected at %p, speed %ld\n",
255 	      plat->ich_version, ctlr->base, ctlr->max_speed);
256 
257 	ich_set_bbar(ctlr, 0);
258 
259 	return 0;
260 }
261 
262 static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
263 {
264 	trans->out += bytes;
265 	trans->bytesout -= bytes;
266 }
267 
268 static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
269 {
270 	trans->in += bytes;
271 	trans->bytesin -= bytes;
272 }
273 
274 static void spi_setup_type(struct spi_trans *trans, int data_bytes)
275 {
276 	trans->type = 0xFF;
277 
278 	/* Try to guess spi type from read/write sizes. */
279 	if (trans->bytesin == 0) {
280 		if (trans->bytesout + data_bytes > 4)
281 			/*
282 			 * If bytesin = 0 and bytesout > 4, we presume this is
283 			 * a write data operation, which is accompanied by an
284 			 * address.
285 			 */
286 			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
287 		else
288 			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
289 		return;
290 	}
291 
292 	if (trans->bytesout == 1) {	/* and bytesin is > 0 */
293 		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
294 		return;
295 	}
296 
297 	if (trans->bytesout == 4)	/* and bytesin is > 0 */
298 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
299 
300 	/* Fast read command is called with 5 bytes instead of 4 */
301 	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
302 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
303 		--trans->bytesout;
304 	}
305 }
306 
307 static int spi_setup_opcode(struct ich_spi_priv *ctlr, struct spi_trans *trans)
308 {
309 	uint16_t optypes;
310 	uint8_t opmenu[ctlr->menubytes];
311 
312 	trans->opcode = trans->out[0];
313 	spi_use_out(trans, 1);
314 	if (!ctlr->ichspi_lock) {
315 		/* The lock is off, so just use index 0. */
316 		ich_writeb(ctlr, trans->opcode, ctlr->opmenu);
317 		optypes = ich_readw(ctlr, ctlr->optype);
318 		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
319 		ich_writew(ctlr, optypes, ctlr->optype);
320 		return 0;
321 	} else {
322 		/* The lock is on. See if what we need is on the menu. */
323 		uint8_t optype;
324 		uint16_t opcode_index;
325 
326 		/* Write Enable is handled as atomic prefix */
327 		if (trans->opcode == SPI_OPCODE_WREN)
328 			return 0;
329 
330 		read_reg(ctlr, ctlr->opmenu, opmenu, sizeof(opmenu));
331 		for (opcode_index = 0; opcode_index < ctlr->menubytes;
332 				opcode_index++) {
333 			if (opmenu[opcode_index] == trans->opcode)
334 				break;
335 		}
336 
337 		if (opcode_index == ctlr->menubytes) {
338 			printf("ICH SPI: Opcode %x not found\n",
339 			       trans->opcode);
340 			return -EINVAL;
341 		}
342 
343 		optypes = ich_readw(ctlr, ctlr->optype);
344 		optype = (optypes >> (opcode_index * 2)) & 0x3;
345 		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
346 		    optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
347 		    trans->bytesout >= 3) {
348 			/* We guessed wrong earlier. Fix it up. */
349 			trans->type = optype;
350 		}
351 		if (optype != trans->type) {
352 			printf("ICH SPI: Transaction doesn't fit type %d\n",
353 			       optype);
354 			return -ENOSPC;
355 		}
356 		return opcode_index;
357 	}
358 }
359 
360 static int spi_setup_offset(struct spi_trans *trans)
361 {
362 	/* Separate the SPI address and data. */
363 	switch (trans->type) {
364 	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
365 	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
366 		return 0;
367 	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
368 	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
369 		trans->offset = ((uint32_t)trans->out[0] << 16) |
370 				((uint32_t)trans->out[1] << 8) |
371 				((uint32_t)trans->out[2] << 0);
372 		spi_use_out(trans, 3);
373 		return 1;
374 	default:
375 		printf("Unrecognized SPI transaction type %#x\n", trans->type);
376 		return -EPROTO;
377 	}
378 }
379 
380 /*
381  * Wait for up to 6s til status register bit(s) turn 1 (in case wait_til_set
382  * below is true) or 0. In case the wait was for the bit(s) to set - write
383  * those bits back, which would cause resetting them.
384  *
385  * Return the last read status value on success or -1 on failure.
386  */
387 static int ich_status_poll(struct ich_spi_priv *ctlr, u16 bitmask,
388 			   int wait_til_set)
389 {
390 	int timeout = 600000; /* This will result in 6s */
391 	u16 status = 0;
392 
393 	while (timeout--) {
394 		status = ich_readw(ctlr, ctlr->status);
395 		if (wait_til_set ^ ((status & bitmask) == 0)) {
396 			if (wait_til_set) {
397 				ich_writew(ctlr, status & bitmask,
398 					   ctlr->status);
399 			}
400 			return status;
401 		}
402 		udelay(10);
403 	}
404 
405 	printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
406 	       status, bitmask);
407 	return -ETIMEDOUT;
408 }
409 
410 static int ich_spi_xfer(struct udevice *dev, unsigned int bitlen,
411 			const void *dout, void *din, unsigned long flags)
412 {
413 	struct udevice *bus = dev_get_parent(dev);
414 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
415 	uint16_t control;
416 	int16_t opcode_index;
417 	int with_address;
418 	int status;
419 	int bytes = bitlen / 8;
420 	struct spi_trans *trans = &ctlr->trans;
421 	unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
422 	int using_cmd = 0;
423 	int ret;
424 
425 	/* Ee don't support writing partial bytes. */
426 	if (bitlen % 8) {
427 		debug("ICH SPI: Accessing partial bytes not supported\n");
428 		return -EPROTONOSUPPORT;
429 	}
430 
431 	/* An empty end transaction can be ignored */
432 	if (type == SPI_XFER_END && !dout && !din)
433 		return 0;
434 
435 	if (type & SPI_XFER_BEGIN)
436 		memset(trans, '\0', sizeof(*trans));
437 
438 	/* Dp we need to come back later to finish it? */
439 	if (dout && type == SPI_XFER_BEGIN) {
440 		if (bytes > ICH_MAX_CMD_LEN) {
441 			debug("ICH SPI: Command length limit exceeded\n");
442 			return -ENOSPC;
443 		}
444 		memcpy(trans->cmd, dout, bytes);
445 		trans->cmd_len = bytes;
446 		debug("ICH SPI: Saved %d bytes\n", bytes);
447 		return 0;
448 	}
449 
450 	/*
451 	 * We process a 'middle' spi_xfer() call, which has no
452 	 * SPI_XFER_BEGIN/END, as an independent transaction as if it had
453 	 * an end. We therefore repeat the command. This is because ICH
454 	 * seems to have no support for this, or because interest (in digging
455 	 * out the details and creating a special case in the code) is low.
456 	 */
457 	if (trans->cmd_len) {
458 		trans->out = trans->cmd;
459 		trans->bytesout = trans->cmd_len;
460 		using_cmd = 1;
461 		debug("ICH SPI: Using %d bytes\n", trans->cmd_len);
462 	} else {
463 		trans->out = dout;
464 		trans->bytesout = dout ? bytes : 0;
465 	}
466 
467 	trans->in = din;
468 	trans->bytesin = din ? bytes : 0;
469 
470 	/* There has to always at least be an opcode. */
471 	if (!trans->bytesout) {
472 		debug("ICH SPI: No opcode for transfer\n");
473 		return -EPROTO;
474 	}
475 
476 	ret = ich_status_poll(ctlr, SPIS_SCIP, 0);
477 	if (ret < 0)
478 		return ret;
479 
480 	ich_writew(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
481 
482 	spi_setup_type(trans, using_cmd ? bytes : 0);
483 	opcode_index = spi_setup_opcode(ctlr, trans);
484 	if (opcode_index < 0)
485 		return -EINVAL;
486 	with_address = spi_setup_offset(trans);
487 	if (with_address < 0)
488 		return -EINVAL;
489 
490 	if (trans->opcode == SPI_OPCODE_WREN) {
491 		/*
492 		 * Treat Write Enable as Atomic Pre-Op if possible
493 		 * in order to prevent the Management Engine from
494 		 * issuing a transaction between WREN and DATA.
495 		 */
496 		if (!ctlr->ichspi_lock)
497 			ich_writew(ctlr, trans->opcode, ctlr->preop);
498 		return 0;
499 	}
500 
501 	if (ctlr->speed && ctlr->max_speed >= 33000000) {
502 		int byte;
503 
504 		byte = ich_readb(ctlr, ctlr->speed);
505 		if (ctlr->cur_speed >= 33000000)
506 			byte |= SSFC_SCF_33MHZ;
507 		else
508 			byte &= ~SSFC_SCF_33MHZ;
509 		ich_writeb(ctlr, byte, ctlr->speed);
510 	}
511 
512 	/* See if we have used up the command data */
513 	if (using_cmd && dout && bytes) {
514 		trans->out = dout;
515 		trans->bytesout = bytes;
516 		debug("ICH SPI: Moving to data, %d bytes\n", bytes);
517 	}
518 
519 	/* Preset control fields */
520 	control = ich_readw(ctlr, ctlr->control);
521 	control &= ~SSFC_RESERVED;
522 	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
523 
524 	/* Issue atomic preop cycle if needed */
525 	if (ich_readw(ctlr, ctlr->preop))
526 		control |= SPIC_ACS;
527 
528 	if (!trans->bytesout && !trans->bytesin) {
529 		/* SPI addresses are 24 bit only */
530 		if (with_address) {
531 			ich_writel(ctlr, trans->offset & 0x00FFFFFF,
532 				   ctlr->addr);
533 		}
534 		/*
535 		 * This is a 'no data' command (like Write Enable), its
536 		 * bitesout size was 1, decremented to zero while executing
537 		 * spi_setup_opcode() above. Tell the chip to send the
538 		 * command.
539 		 */
540 		ich_writew(ctlr, control, ctlr->control);
541 
542 		/* wait for the result */
543 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
544 		if (status < 0)
545 			return status;
546 
547 		if (status & SPIS_FCERR) {
548 			debug("ICH SPI: Command transaction error\n");
549 			return -EIO;
550 		}
551 
552 		return 0;
553 	}
554 
555 	/*
556 	 * Check if this is a write command atempting to transfer more bytes
557 	 * than the controller can handle. Iterations for writes are not
558 	 * supported here because each SPI write command needs to be preceded
559 	 * and followed by other SPI commands, and this sequence is controlled
560 	 * by the SPI chip driver.
561 	 */
562 	if (trans->bytesout > ctlr->databytes) {
563 		debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
564 		return -EPROTO;
565 	}
566 
567 	/*
568 	 * Read or write up to databytes bytes at a time until everything has
569 	 * been sent.
570 	 */
571 	while (trans->bytesout || trans->bytesin) {
572 		uint32_t data_length;
573 
574 		/* SPI addresses are 24 bit only */
575 		ich_writel(ctlr, trans->offset & 0x00FFFFFF, ctlr->addr);
576 
577 		if (trans->bytesout)
578 			data_length = min(trans->bytesout, ctlr->databytes);
579 		else
580 			data_length = min(trans->bytesin, ctlr->databytes);
581 
582 		/* Program data into FDATA0 to N */
583 		if (trans->bytesout) {
584 			write_reg(ctlr, trans->out, ctlr->data, data_length);
585 			spi_use_out(trans, data_length);
586 			if (with_address)
587 				trans->offset += data_length;
588 		}
589 
590 		/* Add proper control fields' values */
591 		control &= ~((ctlr->databytes - 1) << 8);
592 		control |= SPIC_DS;
593 		control |= (data_length - 1) << 8;
594 
595 		/* write it */
596 		ich_writew(ctlr, control, ctlr->control);
597 
598 		/* Wait for Cycle Done Status or Flash Cycle Error. */
599 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
600 		if (status < 0)
601 			return status;
602 
603 		if (status & SPIS_FCERR) {
604 			debug("ICH SPI: Data transaction error\n");
605 			return -EIO;
606 		}
607 
608 		if (trans->bytesin) {
609 			read_reg(ctlr, ctlr->data, trans->in, data_length);
610 			spi_use_in(trans, data_length);
611 			if (with_address)
612 				trans->offset += data_length;
613 		}
614 	}
615 
616 	/* Clear atomic preop now that xfer is done */
617 	ich_writew(ctlr, 0, ctlr->preop);
618 
619 	return 0;
620 }
621 
622 
623 /*
624  * This uses the SPI controller from the Intel Cougar Point and Panther Point
625  * PCH to write-protect portions of the SPI flash until reboot. The changes
626  * don't actually take effect until the HSFS[FLOCKDN] bit is set, but that's
627  * done elsewhere.
628  */
629 int spi_write_protect_region(struct udevice *dev, uint32_t lower_limit,
630 			     uint32_t length, int hint)
631 {
632 	struct udevice *bus = dev->parent;
633 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
634 	uint32_t tmplong;
635 	uint32_t upper_limit;
636 
637 	if (!ctlr->pr) {
638 		printf("%s: operation not supported on this chipset\n",
639 		       __func__);
640 		return -ENOSYS;
641 	}
642 
643 	if (length == 0 ||
644 	    lower_limit > (0xFFFFFFFFUL - length) + 1 ||
645 	    hint < 0 || hint > 4) {
646 		printf("%s(0x%x, 0x%x, %d): invalid args\n", __func__,
647 		       lower_limit, length, hint);
648 		return -EPERM;
649 	}
650 
651 	upper_limit = lower_limit + length - 1;
652 
653 	/*
654 	 * Determine bits to write, as follows:
655 	 *  31     Write-protection enable (includes erase operation)
656 	 *  30:29  reserved
657 	 *  28:16  Upper Limit (FLA address bits 24:12, with 11:0 == 0xfff)
658 	 *  15     Read-protection enable
659 	 *  14:13  reserved
660 	 *  12:0   Lower Limit (FLA address bits 24:12, with 11:0 == 0x000)
661 	 */
662 	tmplong = 0x80000000 |
663 		((upper_limit & 0x01fff000) << 4) |
664 		((lower_limit & 0x01fff000) >> 12);
665 
666 	printf("%s: writing 0x%08x to %p\n", __func__, tmplong,
667 	       &ctlr->pr[hint]);
668 	ctlr->pr[hint] = tmplong;
669 
670 	return 0;
671 }
672 
673 static int ich_spi_probe(struct udevice *bus)
674 {
675 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
676 	struct ich_spi_priv *priv = dev_get_priv(bus);
677 	uint8_t bios_cntl;
678 	int ret;
679 
680 	ret = ich_init_controller(plat, priv);
681 	if (ret)
682 		return ret;
683 	/*
684 	 * Disable the BIOS write protect so write commands are allowed.  On
685 	 * v9, deassert SMM BIOS Write Protect Disable.
686 	 */
687 	if (plat->use_sbase) {
688 		struct ich9_spi_regs *ich9_spi;
689 
690 		ich9_spi = priv->base;
691 		bios_cntl = ich_readb(priv, ich9_spi->bcr);
692 		bios_cntl &= ~(1 << 5);	/* clear Enable InSMM_STS (EISS) */
693 		bios_cntl |= 1;		/* Write Protect Disable (WPD) */
694 		ich_writeb(priv, bios_cntl, ich9_spi->bcr);
695 	} else {
696 		pci_read_config_byte(plat->dev, 0xdc, &bios_cntl);
697 		if (plat->ich_version == 9)
698 			bios_cntl &= ~(1 << 5);
699 		pci_write_config_byte(plat->dev, 0xdc, bios_cntl | 0x1);
700 	}
701 
702 	priv->cur_speed = priv->max_speed;
703 
704 	return 0;
705 }
706 
707 static int ich_spi_ofdata_to_platdata(struct udevice *bus)
708 {
709 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
710 	int ret;
711 
712 	ret = ich_find_spi_controller(plat);
713 	if (ret)
714 		return ret;
715 
716 	return 0;
717 }
718 
719 static int ich_spi_set_speed(struct udevice *bus, uint speed)
720 {
721 	struct ich_spi_priv *priv = dev_get_priv(bus);
722 
723 	priv->cur_speed = speed;
724 
725 	return 0;
726 }
727 
728 static int ich_spi_set_mode(struct udevice *bus, uint mode)
729 {
730 	debug("%s: mode=%d\n", __func__, mode);
731 
732 	return 0;
733 }
734 
735 static int ich_spi_child_pre_probe(struct udevice *dev)
736 {
737 	struct udevice *bus = dev_get_parent(dev);
738 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
739 	struct ich_spi_priv *priv = dev_get_priv(bus);
740 	struct spi_slave *slave = dev_get_parentdata(dev);
741 
742 	/*
743 	 * Yes this controller can only write a small number of bytes at
744 	 * once! The limit is typically 64 bytes.
745 	 */
746 	slave->max_write_size = priv->databytes;
747 	/*
748 	 * ICH 7 SPI controller only supports array read command
749 	 * and byte program command for SST flash
750 	 */
751 	if (plat->ich_version == 7) {
752 		slave->op_mode_rx = SPI_OPM_RX_AS;
753 		slave->op_mode_tx = SPI_OPM_TX_BP;
754 	}
755 
756 	return 0;
757 }
758 
759 static const struct dm_spi_ops ich_spi_ops = {
760 	.xfer		= ich_spi_xfer,
761 	.set_speed	= ich_spi_set_speed,
762 	.set_mode	= ich_spi_set_mode,
763 	/*
764 	 * cs_info is not needed, since we require all chip selects to be
765 	 * in the device tree explicitly
766 	 */
767 };
768 
769 static const struct udevice_id ich_spi_ids[] = {
770 	{ .compatible = "intel,ich-spi" },
771 	{ }
772 };
773 
774 U_BOOT_DRIVER(ich_spi) = {
775 	.name	= "ich_spi",
776 	.id	= UCLASS_SPI,
777 	.of_match = ich_spi_ids,
778 	.ops	= &ich_spi_ops,
779 	.ofdata_to_platdata = ich_spi_ofdata_to_platdata,
780 	.platdata_auto_alloc_size = sizeof(struct ich_spi_platdata),
781 	.priv_auto_alloc_size = sizeof(struct ich_spi_priv),
782 	.child_pre_probe = ich_spi_child_pre_probe,
783 	.probe	= ich_spi_probe,
784 };
785