xref: /openbmc/u-boot/drivers/spi/ich.c (revision 29b103c7)
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 	int bcr;
44 	uint32_t *pr;		/* only for ich9 */
45 	int speed;		/* pointer to speed control */
46 	ulong max_speed;	/* Maximum bus speed in MHz */
47 	ulong cur_speed;	/* Current bus speed */
48 	struct spi_trans trans;	/* current transaction in progress */
49 };
50 
51 static u8 ich_readb(struct ich_spi_priv *priv, int reg)
52 {
53 	u8 value = readb(priv->base + reg);
54 
55 	debug("read %2.2x from %4.4x\n", value, reg);
56 
57 	return value;
58 }
59 
60 static u16 ich_readw(struct ich_spi_priv *priv, int reg)
61 {
62 	u16 value = readw(priv->base + reg);
63 
64 	debug("read %4.4x from %4.4x\n", value, reg);
65 
66 	return value;
67 }
68 
69 static u32 ich_readl(struct ich_spi_priv *priv, int reg)
70 {
71 	u32 value = readl(priv->base + reg);
72 
73 	debug("read %8.8x from %4.4x\n", value, reg);
74 
75 	return value;
76 }
77 
78 static void ich_writeb(struct ich_spi_priv *priv, u8 value, int reg)
79 {
80 	writeb(value, priv->base + reg);
81 	debug("wrote %2.2x to %4.4x\n", value, reg);
82 }
83 
84 static void ich_writew(struct ich_spi_priv *priv, u16 value, int reg)
85 {
86 	writew(value, priv->base + reg);
87 	debug("wrote %4.4x to %4.4x\n", value, reg);
88 }
89 
90 static void ich_writel(struct ich_spi_priv *priv, u32 value, int reg)
91 {
92 	writel(value, priv->base + reg);
93 	debug("wrote %8.8x to %4.4x\n", value, reg);
94 }
95 
96 static void write_reg(struct ich_spi_priv *priv, const void *value,
97 		      int dest_reg, uint32_t size)
98 {
99 	memcpy_toio(priv->base + dest_reg, value, size);
100 }
101 
102 static void read_reg(struct ich_spi_priv *priv, int src_reg, void *value,
103 		     uint32_t size)
104 {
105 	memcpy_fromio(value, priv->base + src_reg, size);
106 }
107 
108 static void ich_set_bbar(struct ich_spi_priv *ctlr, uint32_t minaddr)
109 {
110 	const uint32_t bbar_mask = 0x00ffff00;
111 	uint32_t ichspi_bbar;
112 
113 	minaddr &= bbar_mask;
114 	ichspi_bbar = ich_readl(ctlr, ctlr->bbar) & ~bbar_mask;
115 	ichspi_bbar |= minaddr;
116 	ich_writel(ctlr, ichspi_bbar, ctlr->bbar);
117 }
118 
119 /*
120  * Check if this device ID matches one of supported Intel PCH devices.
121  *
122  * Return the ICH version if there is a match, or zero otherwise.
123  */
124 static int get_ich_version(uint16_t device_id)
125 {
126 	if (device_id == PCI_DEVICE_ID_INTEL_TGP_LPC ||
127 	    device_id == PCI_DEVICE_ID_INTEL_ITC_LPC ||
128 	    device_id == PCI_DEVICE_ID_INTEL_QRK_ILB)
129 		return 7;
130 
131 	if ((device_id >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
132 	     device_id <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX) ||
133 	    (device_id >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
134 	     device_id <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX) ||
135 	    device_id == PCI_DEVICE_ID_INTEL_VALLEYVIEW_LPC ||
136 	    device_id == PCI_DEVICE_ID_INTEL_LYNXPOINT_LPC)
137 		return 9;
138 
139 	return 0;
140 }
141 
142 /* @return 1 if the SPI flash supports the 33MHz speed */
143 static int ich9_can_do_33mhz(pci_dev_t dev)
144 {
145 	u32 fdod, speed;
146 
147 	/* Observe SPI Descriptor Component Section 0 */
148 	pci_write_config_dword(dev, 0xb0, 0x1000);
149 
150 	/* Extract the Write/Erase SPI Frequency from descriptor */
151 	pci_read_config_dword(dev, 0xb4, &fdod);
152 
153 	/* Bits 23:21 have the fast read clock frequency, 0=20MHz, 1=33MHz */
154 	speed = (fdod >> 21) & 7;
155 
156 	return speed == 1;
157 }
158 
159 static int ich_find_spi_controller(struct ich_spi_platdata *ich)
160 {
161 	int last_bus = pci_last_busno();
162 	int bus;
163 
164 	if (last_bus == -1) {
165 		debug("No PCI busses?\n");
166 		return -ENODEV;
167 	}
168 
169 	for (bus = 0; bus <= last_bus; bus++) {
170 		uint16_t vendor_id, device_id;
171 		uint32_t ids;
172 		pci_dev_t dev;
173 
174 		dev = PCI_BDF(bus, 31, 0);
175 		pci_read_config_dword(dev, 0, &ids);
176 		vendor_id = ids;
177 		device_id = ids >> 16;
178 
179 		if (vendor_id == PCI_VENDOR_ID_INTEL) {
180 			ich->dev = dev;
181 			ich->ich_version = get_ich_version(device_id);
182 			if (device_id == PCI_DEVICE_ID_INTEL_VALLEYVIEW_LPC)
183 				ich->use_sbase = true;
184 			return ich->ich_version == 0 ? -ENODEV : 0;
185 		}
186 	}
187 
188 	debug("ICH SPI: No ICH found.\n");
189 	return -ENODEV;
190 }
191 
192 static int ich_init_controller(struct ich_spi_platdata *plat,
193 			       struct ich_spi_priv *ctlr)
194 {
195 	uint8_t *rcrb; /* Root Complex Register Block */
196 	uint32_t rcba; /* Root Complex Base Address */
197 	uint32_t sbase_addr;
198 	uint8_t *sbase;
199 
200 	pci_read_config_dword(plat->dev, 0xf0, &rcba);
201 	/* Bits 31-14 are the base address, 13-1 are reserved, 0 is enable. */
202 	rcrb = (uint8_t *)(rcba & 0xffffc000);
203 
204 	/* SBASE is similar */
205 	pci_read_config_dword(plat->dev, 0x54, &sbase_addr);
206 	sbase = (uint8_t *)(sbase_addr & 0xfffffe00);
207 
208 	if (plat->ich_version == 7) {
209 		struct ich7_spi_regs *ich7_spi;
210 
211 		ich7_spi = (struct ich7_spi_regs *)(rcrb + 0x3020);
212 		ctlr->ichspi_lock = readw(&ich7_spi->spis) & SPIS_LOCK;
213 		ctlr->opmenu = offsetof(struct ich7_spi_regs, opmenu);
214 		ctlr->menubytes = sizeof(ich7_spi->opmenu);
215 		ctlr->optype = offsetof(struct ich7_spi_regs, optype);
216 		ctlr->addr = offsetof(struct ich7_spi_regs, spia);
217 		ctlr->data = offsetof(struct ich7_spi_regs, spid);
218 		ctlr->databytes = sizeof(ich7_spi->spid);
219 		ctlr->status = offsetof(struct ich7_spi_regs, spis);
220 		ctlr->control = offsetof(struct ich7_spi_regs, spic);
221 		ctlr->bbar = offsetof(struct ich7_spi_regs, bbar);
222 		ctlr->preop = offsetof(struct ich7_spi_regs, preop);
223 		ctlr->base = ich7_spi;
224 	} else if (plat->ich_version == 9) {
225 		struct ich9_spi_regs *ich9_spi;
226 
227 		if (plat->use_sbase)
228 			ich9_spi = (struct ich9_spi_regs *)sbase;
229 		else
230 			ich9_spi = (struct ich9_spi_regs *)(rcrb + 0x3800);
231 		ctlr->ichspi_lock = readw(&ich9_spi->hsfs) & HSFS_FLOCKDN;
232 		ctlr->opmenu = offsetof(struct ich9_spi_regs, opmenu);
233 		ctlr->menubytes = sizeof(ich9_spi->opmenu);
234 		ctlr->optype = offsetof(struct ich9_spi_regs, optype);
235 		ctlr->addr = offsetof(struct ich9_spi_regs, faddr);
236 		ctlr->data = offsetof(struct ich9_spi_regs, fdata);
237 		ctlr->databytes = sizeof(ich9_spi->fdata);
238 		ctlr->status = offsetof(struct ich9_spi_regs, ssfs);
239 		ctlr->control = offsetof(struct ich9_spi_regs, ssfc);
240 		ctlr->speed = ctlr->control + 2;
241 		ctlr->bbar = offsetof(struct ich9_spi_regs, bbar);
242 		ctlr->preop = offsetof(struct ich9_spi_regs, preop);
243 		ctlr->bcr = offsetof(struct ich9_spi_regs, bcr);
244 		ctlr->pr = &ich9_spi->pr[0];
245 		ctlr->base = ich9_spi;
246 	} else {
247 		debug("ICH SPI: Unrecognised ICH version %d\n",
248 		      plat->ich_version);
249 		return -EINVAL;
250 	}
251 
252 	/* Work out the maximum speed we can support */
253 	ctlr->max_speed = 20000000;
254 	if (plat->ich_version == 9 && ich9_can_do_33mhz(plat->dev))
255 		ctlr->max_speed = 33000000;
256 	debug("ICH SPI: Version %d detected at %p, speed %ld\n",
257 	      plat->ich_version, ctlr->base, ctlr->max_speed);
258 
259 	ich_set_bbar(ctlr, 0);
260 
261 	return 0;
262 }
263 
264 static inline void spi_use_out(struct spi_trans *trans, unsigned bytes)
265 {
266 	trans->out += bytes;
267 	trans->bytesout -= bytes;
268 }
269 
270 static inline void spi_use_in(struct spi_trans *trans, unsigned bytes)
271 {
272 	trans->in += bytes;
273 	trans->bytesin -= bytes;
274 }
275 
276 static void spi_setup_type(struct spi_trans *trans, int data_bytes)
277 {
278 	trans->type = 0xFF;
279 
280 	/* Try to guess spi type from read/write sizes. */
281 	if (trans->bytesin == 0) {
282 		if (trans->bytesout + data_bytes > 4)
283 			/*
284 			 * If bytesin = 0 and bytesout > 4, we presume this is
285 			 * a write data operation, which is accompanied by an
286 			 * address.
287 			 */
288 			trans->type = SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS;
289 		else
290 			trans->type = SPI_OPCODE_TYPE_WRITE_NO_ADDRESS;
291 		return;
292 	}
293 
294 	if (trans->bytesout == 1) {	/* and bytesin is > 0 */
295 		trans->type = SPI_OPCODE_TYPE_READ_NO_ADDRESS;
296 		return;
297 	}
298 
299 	if (trans->bytesout == 4)	/* and bytesin is > 0 */
300 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
301 
302 	/* Fast read command is called with 5 bytes instead of 4 */
303 	if (trans->out[0] == SPI_OPCODE_FAST_READ && trans->bytesout == 5) {
304 		trans->type = SPI_OPCODE_TYPE_READ_WITH_ADDRESS;
305 		--trans->bytesout;
306 	}
307 }
308 
309 static int spi_setup_opcode(struct ich_spi_priv *ctlr, struct spi_trans *trans)
310 {
311 	uint16_t optypes;
312 	uint8_t opmenu[ctlr->menubytes];
313 
314 	trans->opcode = trans->out[0];
315 	spi_use_out(trans, 1);
316 	if (!ctlr->ichspi_lock) {
317 		/* The lock is off, so just use index 0. */
318 		ich_writeb(ctlr, trans->opcode, ctlr->opmenu);
319 		optypes = ich_readw(ctlr, ctlr->optype);
320 		optypes = (optypes & 0xfffc) | (trans->type & 0x3);
321 		ich_writew(ctlr, optypes, ctlr->optype);
322 		return 0;
323 	} else {
324 		/* The lock is on. See if what we need is on the menu. */
325 		uint8_t optype;
326 		uint16_t opcode_index;
327 
328 		/* Write Enable is handled as atomic prefix */
329 		if (trans->opcode == SPI_OPCODE_WREN)
330 			return 0;
331 
332 		read_reg(ctlr, ctlr->opmenu, opmenu, sizeof(opmenu));
333 		for (opcode_index = 0; opcode_index < ctlr->menubytes;
334 				opcode_index++) {
335 			if (opmenu[opcode_index] == trans->opcode)
336 				break;
337 		}
338 
339 		if (opcode_index == ctlr->menubytes) {
340 			printf("ICH SPI: Opcode %x not found\n",
341 			       trans->opcode);
342 			return -EINVAL;
343 		}
344 
345 		optypes = ich_readw(ctlr, ctlr->optype);
346 		optype = (optypes >> (opcode_index * 2)) & 0x3;
347 		if (trans->type == SPI_OPCODE_TYPE_WRITE_NO_ADDRESS &&
348 		    optype == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS &&
349 		    trans->bytesout >= 3) {
350 			/* We guessed wrong earlier. Fix it up. */
351 			trans->type = optype;
352 		}
353 		if (optype != trans->type) {
354 			printf("ICH SPI: Transaction doesn't fit type %d\n",
355 			       optype);
356 			return -ENOSPC;
357 		}
358 		return opcode_index;
359 	}
360 }
361 
362 static int spi_setup_offset(struct spi_trans *trans)
363 {
364 	/* Separate the SPI address and data. */
365 	switch (trans->type) {
366 	case SPI_OPCODE_TYPE_READ_NO_ADDRESS:
367 	case SPI_OPCODE_TYPE_WRITE_NO_ADDRESS:
368 		return 0;
369 	case SPI_OPCODE_TYPE_READ_WITH_ADDRESS:
370 	case SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS:
371 		trans->offset = ((uint32_t)trans->out[0] << 16) |
372 				((uint32_t)trans->out[1] << 8) |
373 				((uint32_t)trans->out[2] << 0);
374 		spi_use_out(trans, 3);
375 		return 1;
376 	default:
377 		printf("Unrecognized SPI transaction type %#x\n", trans->type);
378 		return -EPROTO;
379 	}
380 }
381 
382 /*
383  * Wait for up to 6s til status register bit(s) turn 1 (in case wait_til_set
384  * below is true) or 0. In case the wait was for the bit(s) to set - write
385  * those bits back, which would cause resetting them.
386  *
387  * Return the last read status value on success or -1 on failure.
388  */
389 static int ich_status_poll(struct ich_spi_priv *ctlr, u16 bitmask,
390 			   int wait_til_set)
391 {
392 	int timeout = 600000; /* This will result in 6s */
393 	u16 status = 0;
394 
395 	while (timeout--) {
396 		status = ich_readw(ctlr, ctlr->status);
397 		if (wait_til_set ^ ((status & bitmask) == 0)) {
398 			if (wait_til_set) {
399 				ich_writew(ctlr, status & bitmask,
400 					   ctlr->status);
401 			}
402 			return status;
403 		}
404 		udelay(10);
405 	}
406 
407 	printf("ICH SPI: SCIP timeout, read %x, expected %x\n",
408 	       status, bitmask);
409 	return -ETIMEDOUT;
410 }
411 
412 static int ich_spi_xfer(struct udevice *dev, unsigned int bitlen,
413 			const void *dout, void *din, unsigned long flags)
414 {
415 	struct udevice *bus = dev_get_parent(dev);
416 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
417 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
418 	uint16_t control;
419 	int16_t opcode_index;
420 	int with_address;
421 	int status;
422 	int bytes = bitlen / 8;
423 	struct spi_trans *trans = &ctlr->trans;
424 	unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
425 	int using_cmd = 0;
426 	int ret;
427 
428 	/* We don't support writing partial bytes */
429 	if (bitlen % 8) {
430 		debug("ICH SPI: Accessing partial bytes not supported\n");
431 		return -EPROTONOSUPPORT;
432 	}
433 
434 	/* An empty end transaction can be ignored */
435 	if (type == SPI_XFER_END && !dout && !din)
436 		return 0;
437 
438 	if (type & SPI_XFER_BEGIN)
439 		memset(trans, '\0', sizeof(*trans));
440 
441 	/* Dp we need to come back later to finish it? */
442 	if (dout && type == SPI_XFER_BEGIN) {
443 		if (bytes > ICH_MAX_CMD_LEN) {
444 			debug("ICH SPI: Command length limit exceeded\n");
445 			return -ENOSPC;
446 		}
447 		memcpy(trans->cmd, dout, bytes);
448 		trans->cmd_len = bytes;
449 		debug("ICH SPI: Saved %d bytes\n", bytes);
450 		return 0;
451 	}
452 
453 	/*
454 	 * We process a 'middle' spi_xfer() call, which has no
455 	 * SPI_XFER_BEGIN/END, as an independent transaction as if it had
456 	 * an end. We therefore repeat the command. This is because ICH
457 	 * seems to have no support for this, or because interest (in digging
458 	 * out the details and creating a special case in the code) is low.
459 	 */
460 	if (trans->cmd_len) {
461 		trans->out = trans->cmd;
462 		trans->bytesout = trans->cmd_len;
463 		using_cmd = 1;
464 		debug("ICH SPI: Using %d bytes\n", trans->cmd_len);
465 	} else {
466 		trans->out = dout;
467 		trans->bytesout = dout ? bytes : 0;
468 	}
469 
470 	trans->in = din;
471 	trans->bytesin = din ? bytes : 0;
472 
473 	/* There has to always at least be an opcode. */
474 	if (!trans->bytesout) {
475 		debug("ICH SPI: No opcode for transfer\n");
476 		return -EPROTO;
477 	}
478 
479 	ret = ich_status_poll(ctlr, SPIS_SCIP, 0);
480 	if (ret < 0)
481 		return ret;
482 
483 	if (plat->ich_version == 7)
484 		ich_writew(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
485 	else
486 		ich_writeb(ctlr, SPIS_CDS | SPIS_FCERR, ctlr->status);
487 
488 	spi_setup_type(trans, using_cmd ? bytes : 0);
489 	opcode_index = spi_setup_opcode(ctlr, trans);
490 	if (opcode_index < 0)
491 		return -EINVAL;
492 	with_address = spi_setup_offset(trans);
493 	if (with_address < 0)
494 		return -EINVAL;
495 
496 	if (trans->opcode == SPI_OPCODE_WREN) {
497 		/*
498 		 * Treat Write Enable as Atomic Pre-Op if possible
499 		 * in order to prevent the Management Engine from
500 		 * issuing a transaction between WREN and DATA.
501 		 */
502 		if (!ctlr->ichspi_lock)
503 			ich_writew(ctlr, trans->opcode, ctlr->preop);
504 		return 0;
505 	}
506 
507 	if (ctlr->speed && ctlr->max_speed >= 33000000) {
508 		int byte;
509 
510 		byte = ich_readb(ctlr, ctlr->speed);
511 		if (ctlr->cur_speed >= 33000000)
512 			byte |= SSFC_SCF_33MHZ;
513 		else
514 			byte &= ~SSFC_SCF_33MHZ;
515 		ich_writeb(ctlr, byte, ctlr->speed);
516 	}
517 
518 	/* See if we have used up the command data */
519 	if (using_cmd && dout && bytes) {
520 		trans->out = dout;
521 		trans->bytesout = bytes;
522 		debug("ICH SPI: Moving to data, %d bytes\n", bytes);
523 	}
524 
525 	/* Preset control fields */
526 	control = ich_readw(ctlr, ctlr->control);
527 	control &= ~SSFC_RESERVED;
528 	control = SPIC_SCGO | ((opcode_index & 0x07) << 4);
529 
530 	/* Issue atomic preop cycle if needed */
531 	if (ich_readw(ctlr, ctlr->preop))
532 		control |= SPIC_ACS;
533 
534 	if (!trans->bytesout && !trans->bytesin) {
535 		/* SPI addresses are 24 bit only */
536 		if (with_address) {
537 			ich_writel(ctlr, trans->offset & 0x00FFFFFF,
538 				   ctlr->addr);
539 		}
540 		/*
541 		 * This is a 'no data' command (like Write Enable), its
542 		 * bitesout size was 1, decremented to zero while executing
543 		 * spi_setup_opcode() above. Tell the chip to send the
544 		 * command.
545 		 */
546 		ich_writew(ctlr, control, ctlr->control);
547 
548 		/* wait for the result */
549 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
550 		if (status < 0)
551 			return status;
552 
553 		if (status & SPIS_FCERR) {
554 			debug("ICH SPI: Command transaction error\n");
555 			return -EIO;
556 		}
557 
558 		return 0;
559 	}
560 
561 	/*
562 	 * Check if this is a write command atempting to transfer more bytes
563 	 * than the controller can handle. Iterations for writes are not
564 	 * supported here because each SPI write command needs to be preceded
565 	 * and followed by other SPI commands, and this sequence is controlled
566 	 * by the SPI chip driver.
567 	 */
568 	if (trans->bytesout > ctlr->databytes) {
569 		debug("ICH SPI: Too much to write. This should be prevented by the driver's max_write_size?\n");
570 		return -EPROTO;
571 	}
572 
573 	/*
574 	 * Read or write up to databytes bytes at a time until everything has
575 	 * been sent.
576 	 */
577 	while (trans->bytesout || trans->bytesin) {
578 		uint32_t data_length;
579 
580 		/* SPI addresses are 24 bit only */
581 		ich_writel(ctlr, trans->offset & 0x00FFFFFF, ctlr->addr);
582 
583 		if (trans->bytesout)
584 			data_length = min(trans->bytesout, ctlr->databytes);
585 		else
586 			data_length = min(trans->bytesin, ctlr->databytes);
587 
588 		/* Program data into FDATA0 to N */
589 		if (trans->bytesout) {
590 			write_reg(ctlr, trans->out, ctlr->data, data_length);
591 			spi_use_out(trans, data_length);
592 			if (with_address)
593 				trans->offset += data_length;
594 		}
595 
596 		/* Add proper control fields' values */
597 		control &= ~((ctlr->databytes - 1) << 8);
598 		control |= SPIC_DS;
599 		control |= (data_length - 1) << 8;
600 
601 		/* write it */
602 		ich_writew(ctlr, control, ctlr->control);
603 
604 		/* Wait for Cycle Done Status or Flash Cycle Error. */
605 		status = ich_status_poll(ctlr, SPIS_CDS | SPIS_FCERR, 1);
606 		if (status < 0)
607 			return status;
608 
609 		if (status & SPIS_FCERR) {
610 			debug("ICH SPI: Data transaction error %x\n", status);
611 			return -EIO;
612 		}
613 
614 		if (trans->bytesin) {
615 			read_reg(ctlr, ctlr->data, trans->in, data_length);
616 			spi_use_in(trans, data_length);
617 			if (with_address)
618 				trans->offset += data_length;
619 		}
620 	}
621 
622 	/* Clear atomic preop now that xfer is done */
623 	ich_writew(ctlr, 0, ctlr->preop);
624 
625 	return 0;
626 }
627 
628 /*
629  * This uses the SPI controller from the Intel Cougar Point and Panther Point
630  * PCH to write-protect portions of the SPI flash until reboot. The changes
631  * don't actually take effect until the HSFS[FLOCKDN] bit is set, but that's
632  * done elsewhere.
633  */
634 int spi_write_protect_region(struct udevice *dev, uint32_t lower_limit,
635 			     uint32_t length, int hint)
636 {
637 	struct udevice *bus = dev->parent;
638 	struct ich_spi_priv *ctlr = dev_get_priv(bus);
639 	uint32_t tmplong;
640 	uint32_t upper_limit;
641 
642 	if (!ctlr->pr) {
643 		printf("%s: operation not supported on this chipset\n",
644 		       __func__);
645 		return -ENOSYS;
646 	}
647 
648 	if (length == 0 ||
649 	    lower_limit > (0xFFFFFFFFUL - length) + 1 ||
650 	    hint < 0 || hint > 4) {
651 		printf("%s(0x%x, 0x%x, %d): invalid args\n", __func__,
652 		       lower_limit, length, hint);
653 		return -EPERM;
654 	}
655 
656 	upper_limit = lower_limit + length - 1;
657 
658 	/*
659 	 * Determine bits to write, as follows:
660 	 *  31     Write-protection enable (includes erase operation)
661 	 *  30:29  reserved
662 	 *  28:16  Upper Limit (FLA address bits 24:12, with 11:0 == 0xfff)
663 	 *  15     Read-protection enable
664 	 *  14:13  reserved
665 	 *  12:0   Lower Limit (FLA address bits 24:12, with 11:0 == 0x000)
666 	 */
667 	tmplong = 0x80000000 |
668 		((upper_limit & 0x01fff000) << 4) |
669 		((lower_limit & 0x01fff000) >> 12);
670 
671 	printf("%s: writing 0x%08x to %p\n", __func__, tmplong,
672 	       &ctlr->pr[hint]);
673 	ctlr->pr[hint] = tmplong;
674 
675 	return 0;
676 }
677 
678 static int ich_spi_probe(struct udevice *bus)
679 {
680 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
681 	struct ich_spi_priv *priv = dev_get_priv(bus);
682 	uint8_t bios_cntl;
683 	int ret;
684 
685 	ret = ich_init_controller(plat, priv);
686 	if (ret)
687 		return ret;
688 	/*
689 	 * Disable the BIOS write protect so write commands are allowed.  On
690 	 * v9, deassert SMM BIOS Write Protect Disable.
691 	 */
692 	if (plat->use_sbase) {
693 		bios_cntl = ich_readb(priv, priv->bcr);
694 		bios_cntl &= ~(1 << 5);	/* clear Enable InSMM_STS (EISS) */
695 		bios_cntl |= 1;		/* Write Protect Disable (WPD) */
696 		ich_writeb(priv, bios_cntl, priv->bcr);
697 	} else {
698 		pci_read_config_byte(plat->dev, 0xdc, &bios_cntl);
699 		if (plat->ich_version == 9)
700 			bios_cntl &= ~(1 << 5);
701 		pci_write_config_byte(plat->dev, 0xdc, bios_cntl | 0x1);
702 	}
703 
704 	priv->cur_speed = priv->max_speed;
705 
706 	return 0;
707 }
708 
709 static int ich_spi_ofdata_to_platdata(struct udevice *bus)
710 {
711 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
712 	int ret;
713 
714 	ret = ich_find_spi_controller(plat);
715 	if (ret)
716 		return ret;
717 
718 	return 0;
719 }
720 
721 static int ich_spi_set_speed(struct udevice *bus, uint speed)
722 {
723 	struct ich_spi_priv *priv = dev_get_priv(bus);
724 
725 	priv->cur_speed = speed;
726 
727 	return 0;
728 }
729 
730 static int ich_spi_set_mode(struct udevice *bus, uint mode)
731 {
732 	debug("%s: mode=%d\n", __func__, mode);
733 
734 	return 0;
735 }
736 
737 static int ich_spi_child_pre_probe(struct udevice *dev)
738 {
739 	struct udevice *bus = dev_get_parent(dev);
740 	struct ich_spi_platdata *plat = dev_get_platdata(bus);
741 	struct ich_spi_priv *priv = dev_get_priv(bus);
742 	struct spi_slave *slave = dev_get_parentdata(dev);
743 
744 	/*
745 	 * Yes this controller can only write a small number of bytes at
746 	 * once! The limit is typically 64 bytes.
747 	 */
748 	slave->max_write_size = priv->databytes;
749 	/*
750 	 * ICH 7 SPI controller only supports array read command
751 	 * and byte program command for SST flash
752 	 */
753 	if (plat->ich_version == 7) {
754 		slave->op_mode_rx = SPI_OPM_RX_AS;
755 		slave->op_mode_tx = SPI_OPM_TX_BP;
756 	}
757 
758 	return 0;
759 }
760 
761 static const struct dm_spi_ops ich_spi_ops = {
762 	.xfer		= ich_spi_xfer,
763 	.set_speed	= ich_spi_set_speed,
764 	.set_mode	= ich_spi_set_mode,
765 	/*
766 	 * cs_info is not needed, since we require all chip selects to be
767 	 * in the device tree explicitly
768 	 */
769 };
770 
771 static const struct udevice_id ich_spi_ids[] = {
772 	{ .compatible = "intel,ich-spi" },
773 	{ }
774 };
775 
776 U_BOOT_DRIVER(ich_spi) = {
777 	.name	= "ich_spi",
778 	.id	= UCLASS_SPI,
779 	.of_match = ich_spi_ids,
780 	.ops	= &ich_spi_ops,
781 	.ofdata_to_platdata = ich_spi_ofdata_to_platdata,
782 	.platdata_auto_alloc_size = sizeof(struct ich_spi_platdata),
783 	.priv_auto_alloc_size = sizeof(struct ich_spi_priv),
784 	.child_pre_probe = ich_spi_child_pre_probe,
785 	.probe	= ich_spi_probe,
786 };
787