xref: /openbmc/linux/drivers/spi/spi-intel.c (revision 77423a62)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Intel PCH/PCU SPI flash driver.
4  *
5  * Copyright (C) 2016 - 2022, Intel Corporation
6  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
7  */
8 
9 #include <linux/iopoll.h>
10 #include <linux/module.h>
11 
12 #include <linux/mtd/partitions.h>
13 #include <linux/mtd/spi-nor.h>
14 
15 #include <linux/spi/flash.h>
16 #include <linux/spi/spi.h>
17 #include <linux/spi/spi-mem.h>
18 
19 #include "spi-intel.h"
20 
21 /* Offsets are from @ispi->base */
22 #define BFPREG				0x00
23 
24 #define HSFSTS_CTL			0x04
25 #define HSFSTS_CTL_FSMIE		BIT(31)
26 #define HSFSTS_CTL_FDBC_SHIFT		24
27 #define HSFSTS_CTL_FDBC_MASK		(0x3f << HSFSTS_CTL_FDBC_SHIFT)
28 
29 #define HSFSTS_CTL_FCYCLE_SHIFT		17
30 #define HSFSTS_CTL_FCYCLE_MASK		(0x0f << HSFSTS_CTL_FCYCLE_SHIFT)
31 /* HW sequencer opcodes */
32 #define HSFSTS_CTL_FCYCLE_READ		(0x00 << HSFSTS_CTL_FCYCLE_SHIFT)
33 #define HSFSTS_CTL_FCYCLE_WRITE		(0x02 << HSFSTS_CTL_FCYCLE_SHIFT)
34 #define HSFSTS_CTL_FCYCLE_ERASE		(0x03 << HSFSTS_CTL_FCYCLE_SHIFT)
35 #define HSFSTS_CTL_FCYCLE_ERASE_64K	(0x04 << HSFSTS_CTL_FCYCLE_SHIFT)
36 #define HSFSTS_CTL_FCYCLE_RDID		(0x06 << HSFSTS_CTL_FCYCLE_SHIFT)
37 #define HSFSTS_CTL_FCYCLE_WRSR		(0x07 << HSFSTS_CTL_FCYCLE_SHIFT)
38 #define HSFSTS_CTL_FCYCLE_RDSR		(0x08 << HSFSTS_CTL_FCYCLE_SHIFT)
39 
40 #define HSFSTS_CTL_FGO			BIT(16)
41 #define HSFSTS_CTL_FLOCKDN		BIT(15)
42 #define HSFSTS_CTL_FDV			BIT(14)
43 #define HSFSTS_CTL_SCIP			BIT(5)
44 #define HSFSTS_CTL_AEL			BIT(2)
45 #define HSFSTS_CTL_FCERR		BIT(1)
46 #define HSFSTS_CTL_FDONE		BIT(0)
47 
48 #define FADDR				0x08
49 #define DLOCK				0x0c
50 #define FDATA(n)			(0x10 + ((n) * 4))
51 
52 #define FRACC				0x50
53 
54 #define FREG(n)				(0x54 + ((n) * 4))
55 #define FREG_BASE_MASK			0x3fff
56 #define FREG_LIMIT_SHIFT		16
57 #define FREG_LIMIT_MASK			(0x03fff << FREG_LIMIT_SHIFT)
58 
59 /* Offset is from @ispi->pregs */
60 #define PR(n)				((n) * 4)
61 #define PR_WPE				BIT(31)
62 #define PR_LIMIT_SHIFT			16
63 #define PR_LIMIT_MASK			(0x3fff << PR_LIMIT_SHIFT)
64 #define PR_RPE				BIT(15)
65 #define PR_BASE_MASK			0x3fff
66 
67 /* Offsets are from @ispi->sregs */
68 #define SSFSTS_CTL			0x00
69 #define SSFSTS_CTL_FSMIE		BIT(23)
70 #define SSFSTS_CTL_DS			BIT(22)
71 #define SSFSTS_CTL_DBC_SHIFT		16
72 #define SSFSTS_CTL_SPOP			BIT(11)
73 #define SSFSTS_CTL_ACS			BIT(10)
74 #define SSFSTS_CTL_SCGO			BIT(9)
75 #define SSFSTS_CTL_COP_SHIFT		12
76 #define SSFSTS_CTL_FRS			BIT(7)
77 #define SSFSTS_CTL_DOFRS		BIT(6)
78 #define SSFSTS_CTL_AEL			BIT(4)
79 #define SSFSTS_CTL_FCERR		BIT(3)
80 #define SSFSTS_CTL_FDONE		BIT(2)
81 #define SSFSTS_CTL_SCIP			BIT(0)
82 
83 #define PREOP_OPTYPE			0x04
84 #define OPMENU0				0x08
85 #define OPMENU1				0x0c
86 
87 #define OPTYPE_READ_NO_ADDR		0
88 #define OPTYPE_WRITE_NO_ADDR		1
89 #define OPTYPE_READ_WITH_ADDR		2
90 #define OPTYPE_WRITE_WITH_ADDR		3
91 
92 /* CPU specifics */
93 #define BYT_PR				0x74
94 #define BYT_SSFSTS_CTL			0x90
95 #define BYT_FREG_NUM			5
96 #define BYT_PR_NUM			5
97 
98 #define LPT_PR				0x74
99 #define LPT_SSFSTS_CTL			0x90
100 #define LPT_FREG_NUM			5
101 #define LPT_PR_NUM			5
102 
103 #define BXT_PR				0x84
104 #define BXT_SSFSTS_CTL			0xa0
105 #define BXT_FREG_NUM			12
106 #define BXT_PR_NUM			6
107 
108 #define CNL_PR				0x84
109 #define CNL_FREG_NUM			6
110 #define CNL_PR_NUM			5
111 
112 #define LVSCC				0xc4
113 #define UVSCC				0xc8
114 #define ERASE_OPCODE_SHIFT		8
115 #define ERASE_OPCODE_MASK		(0xff << ERASE_OPCODE_SHIFT)
116 #define ERASE_64K_OPCODE_SHIFT		16
117 #define ERASE_64K_OPCODE_MASK		(0xff << ERASE_OPCODE_SHIFT)
118 
119 #define INTEL_SPI_TIMEOUT		5000 /* ms */
120 #define INTEL_SPI_FIFO_SZ		64
121 
122 /**
123  * struct intel_spi - Driver private data
124  * @dev: Device pointer
125  * @info: Pointer to board specific info
126  * @base: Beginning of MMIO space
127  * @pregs: Start of protection registers
128  * @sregs: Start of software sequencer registers
129  * @master: Pointer to the SPI controller structure
130  * @nregions: Maximum number of regions
131  * @pr_num: Maximum number of protected range registers
132  * @locked: Is SPI setting locked
133  * @swseq_reg: Use SW sequencer in register reads/writes
134  * @swseq_erase: Use SW sequencer in erase operation
135  * @atomic_preopcode: Holds preopcode when atomic sequence is requested
136  * @opcodes: Opcodes which are supported. This are programmed by BIOS
137  *           before it locks down the controller.
138  * @mem_ops: Pointer to SPI MEM ops supported by the controller
139  */
140 struct intel_spi {
141 	struct device *dev;
142 	const struct intel_spi_boardinfo *info;
143 	void __iomem *base;
144 	void __iomem *pregs;
145 	void __iomem *sregs;
146 	struct spi_controller *master;
147 	size_t nregions;
148 	size_t pr_num;
149 	bool locked;
150 	bool swseq_reg;
151 	bool swseq_erase;
152 	u8 atomic_preopcode;
153 	u8 opcodes[8];
154 	const struct intel_spi_mem_op *mem_ops;
155 };
156 
157 struct intel_spi_mem_op {
158 	struct spi_mem_op mem_op;
159 	u32 replacement_op;
160 	int (*exec_op)(struct intel_spi *ispi,
161 		       const struct intel_spi_mem_op *iop,
162 		       const struct spi_mem_op *op);
163 };
164 
165 static bool writeable;
166 module_param(writeable, bool, 0);
167 MODULE_PARM_DESC(writeable, "Enable write access to SPI flash chip (default=0)");
168 
169 static void intel_spi_dump_regs(struct intel_spi *ispi)
170 {
171 	u32 value;
172 	int i;
173 
174 	dev_dbg(ispi->dev, "BFPREG=0x%08x\n", readl(ispi->base + BFPREG));
175 
176 	value = readl(ispi->base + HSFSTS_CTL);
177 	dev_dbg(ispi->dev, "HSFSTS_CTL=0x%08x\n", value);
178 	if (value & HSFSTS_CTL_FLOCKDN)
179 		dev_dbg(ispi->dev, "-> Locked\n");
180 
181 	dev_dbg(ispi->dev, "FADDR=0x%08x\n", readl(ispi->base + FADDR));
182 	dev_dbg(ispi->dev, "DLOCK=0x%08x\n", readl(ispi->base + DLOCK));
183 
184 	for (i = 0; i < 16; i++)
185 		dev_dbg(ispi->dev, "FDATA(%d)=0x%08x\n",
186 			i, readl(ispi->base + FDATA(i)));
187 
188 	dev_dbg(ispi->dev, "FRACC=0x%08x\n", readl(ispi->base + FRACC));
189 
190 	for (i = 0; i < ispi->nregions; i++)
191 		dev_dbg(ispi->dev, "FREG(%d)=0x%08x\n", i,
192 			readl(ispi->base + FREG(i)));
193 	for (i = 0; i < ispi->pr_num; i++)
194 		dev_dbg(ispi->dev, "PR(%d)=0x%08x\n", i,
195 			readl(ispi->pregs + PR(i)));
196 
197 	if (ispi->sregs) {
198 		value = readl(ispi->sregs + SSFSTS_CTL);
199 		dev_dbg(ispi->dev, "SSFSTS_CTL=0x%08x\n", value);
200 		dev_dbg(ispi->dev, "PREOP_OPTYPE=0x%08x\n",
201 			readl(ispi->sregs + PREOP_OPTYPE));
202 		dev_dbg(ispi->dev, "OPMENU0=0x%08x\n",
203 			readl(ispi->sregs + OPMENU0));
204 		dev_dbg(ispi->dev, "OPMENU1=0x%08x\n",
205 			readl(ispi->sregs + OPMENU1));
206 	}
207 
208 	dev_dbg(ispi->dev, "LVSCC=0x%08x\n", readl(ispi->base + LVSCC));
209 	dev_dbg(ispi->dev, "UVSCC=0x%08x\n", readl(ispi->base + UVSCC));
210 
211 	dev_dbg(ispi->dev, "Protected regions:\n");
212 	for (i = 0; i < ispi->pr_num; i++) {
213 		u32 base, limit;
214 
215 		value = readl(ispi->pregs + PR(i));
216 		if (!(value & (PR_WPE | PR_RPE)))
217 			continue;
218 
219 		limit = (value & PR_LIMIT_MASK) >> PR_LIMIT_SHIFT;
220 		base = value & PR_BASE_MASK;
221 
222 		dev_dbg(ispi->dev, " %02d base: 0x%08x limit: 0x%08x [%c%c]\n",
223 			i, base << 12, (limit << 12) | 0xfff,
224 			value & PR_WPE ? 'W' : '.', value & PR_RPE ? 'R' : '.');
225 	}
226 
227 	dev_dbg(ispi->dev, "Flash regions:\n");
228 	for (i = 0; i < ispi->nregions; i++) {
229 		u32 region, base, limit;
230 
231 		region = readl(ispi->base + FREG(i));
232 		base = region & FREG_BASE_MASK;
233 		limit = (region & FREG_LIMIT_MASK) >> FREG_LIMIT_SHIFT;
234 
235 		if (base >= limit || (i > 0 && limit == 0))
236 			dev_dbg(ispi->dev, " %02d disabled\n", i);
237 		else
238 			dev_dbg(ispi->dev, " %02d base: 0x%08x limit: 0x%08x\n",
239 				i, base << 12, (limit << 12) | 0xfff);
240 	}
241 
242 	dev_dbg(ispi->dev, "Using %cW sequencer for register access\n",
243 		ispi->swseq_reg ? 'S' : 'H');
244 	dev_dbg(ispi->dev, "Using %cW sequencer for erase operation\n",
245 		ispi->swseq_erase ? 'S' : 'H');
246 }
247 
248 /* Reads max INTEL_SPI_FIFO_SZ bytes from the device fifo */
249 static int intel_spi_read_block(struct intel_spi *ispi, void *buf, size_t size)
250 {
251 	size_t bytes;
252 	int i = 0;
253 
254 	if (size > INTEL_SPI_FIFO_SZ)
255 		return -EINVAL;
256 
257 	while (size > 0) {
258 		bytes = min_t(size_t, size, 4);
259 		memcpy_fromio(buf, ispi->base + FDATA(i), bytes);
260 		size -= bytes;
261 		buf += bytes;
262 		i++;
263 	}
264 
265 	return 0;
266 }
267 
268 /* Writes max INTEL_SPI_FIFO_SZ bytes to the device fifo */
269 static int intel_spi_write_block(struct intel_spi *ispi, const void *buf,
270 				 size_t size)
271 {
272 	size_t bytes;
273 	int i = 0;
274 
275 	if (size > INTEL_SPI_FIFO_SZ)
276 		return -EINVAL;
277 
278 	while (size > 0) {
279 		bytes = min_t(size_t, size, 4);
280 		memcpy_toio(ispi->base + FDATA(i), buf, bytes);
281 		size -= bytes;
282 		buf += bytes;
283 		i++;
284 	}
285 
286 	return 0;
287 }
288 
289 static int intel_spi_wait_hw_busy(struct intel_spi *ispi)
290 {
291 	u32 val;
292 
293 	return readl_poll_timeout(ispi->base + HSFSTS_CTL, val,
294 				  !(val & HSFSTS_CTL_SCIP), 0,
295 				  INTEL_SPI_TIMEOUT * 1000);
296 }
297 
298 static int intel_spi_wait_sw_busy(struct intel_spi *ispi)
299 {
300 	u32 val;
301 
302 	return readl_poll_timeout(ispi->sregs + SSFSTS_CTL, val,
303 				  !(val & SSFSTS_CTL_SCIP), 0,
304 				  INTEL_SPI_TIMEOUT * 1000);
305 }
306 
307 static bool intel_spi_set_writeable(struct intel_spi *ispi)
308 {
309 	if (!ispi->info->set_writeable)
310 		return false;
311 
312 	return ispi->info->set_writeable(ispi->base, ispi->info->data);
313 }
314 
315 static int intel_spi_opcode_index(struct intel_spi *ispi, u8 opcode, int optype)
316 {
317 	int i;
318 	int preop;
319 
320 	if (ispi->locked) {
321 		for (i = 0; i < ARRAY_SIZE(ispi->opcodes); i++)
322 			if (ispi->opcodes[i] == opcode)
323 				return i;
324 
325 		return -EINVAL;
326 	}
327 
328 	/* The lock is off, so just use index 0 */
329 	writel(opcode, ispi->sregs + OPMENU0);
330 	preop = readw(ispi->sregs + PREOP_OPTYPE);
331 	writel(optype << 16 | preop, ispi->sregs + PREOP_OPTYPE);
332 
333 	return 0;
334 }
335 
336 static int intel_spi_hw_cycle(struct intel_spi *ispi, u8 opcode, size_t len)
337 {
338 	u32 val, status;
339 	int ret;
340 
341 	val = readl(ispi->base + HSFSTS_CTL);
342 	val &= ~(HSFSTS_CTL_FCYCLE_MASK | HSFSTS_CTL_FDBC_MASK);
343 
344 	switch (opcode) {
345 	case SPINOR_OP_RDID:
346 		val |= HSFSTS_CTL_FCYCLE_RDID;
347 		break;
348 	case SPINOR_OP_WRSR:
349 		val |= HSFSTS_CTL_FCYCLE_WRSR;
350 		break;
351 	case SPINOR_OP_RDSR:
352 		val |= HSFSTS_CTL_FCYCLE_RDSR;
353 		break;
354 	default:
355 		return -EINVAL;
356 	}
357 
358 	if (len > INTEL_SPI_FIFO_SZ)
359 		return -EINVAL;
360 
361 	val |= (len - 1) << HSFSTS_CTL_FDBC_SHIFT;
362 	val |= HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
363 	val |= HSFSTS_CTL_FGO;
364 	writel(val, ispi->base + HSFSTS_CTL);
365 
366 	ret = intel_spi_wait_hw_busy(ispi);
367 	if (ret)
368 		return ret;
369 
370 	status = readl(ispi->base + HSFSTS_CTL);
371 	if (status & HSFSTS_CTL_FCERR)
372 		return -EIO;
373 	else if (status & HSFSTS_CTL_AEL)
374 		return -EACCES;
375 
376 	return 0;
377 }
378 
379 static int intel_spi_sw_cycle(struct intel_spi *ispi, u8 opcode, size_t len,
380 			      int optype)
381 {
382 	u32 val = 0, status;
383 	u8 atomic_preopcode;
384 	int ret;
385 
386 	ret = intel_spi_opcode_index(ispi, opcode, optype);
387 	if (ret < 0)
388 		return ret;
389 
390 	if (len > INTEL_SPI_FIFO_SZ)
391 		return -EINVAL;
392 
393 	/*
394 	 * Always clear it after each SW sequencer operation regardless
395 	 * of whether it is successful or not.
396 	 */
397 	atomic_preopcode = ispi->atomic_preopcode;
398 	ispi->atomic_preopcode = 0;
399 
400 	/* Only mark 'Data Cycle' bit when there is data to be transferred */
401 	if (len > 0)
402 		val = ((len - 1) << SSFSTS_CTL_DBC_SHIFT) | SSFSTS_CTL_DS;
403 	val |= ret << SSFSTS_CTL_COP_SHIFT;
404 	val |= SSFSTS_CTL_FCERR | SSFSTS_CTL_FDONE;
405 	val |= SSFSTS_CTL_SCGO;
406 	if (atomic_preopcode) {
407 		u16 preop;
408 
409 		switch (optype) {
410 		case OPTYPE_WRITE_NO_ADDR:
411 		case OPTYPE_WRITE_WITH_ADDR:
412 			/* Pick matching preopcode for the atomic sequence */
413 			preop = readw(ispi->sregs + PREOP_OPTYPE);
414 			if ((preop & 0xff) == atomic_preopcode)
415 				; /* Do nothing */
416 			else if ((preop >> 8) == atomic_preopcode)
417 				val |= SSFSTS_CTL_SPOP;
418 			else
419 				return -EINVAL;
420 
421 			/* Enable atomic sequence */
422 			val |= SSFSTS_CTL_ACS;
423 			break;
424 
425 		default:
426 			return -EINVAL;
427 		}
428 	}
429 	writel(val, ispi->sregs + SSFSTS_CTL);
430 
431 	ret = intel_spi_wait_sw_busy(ispi);
432 	if (ret)
433 		return ret;
434 
435 	status = readl(ispi->sregs + SSFSTS_CTL);
436 	if (status & SSFSTS_CTL_FCERR)
437 		return -EIO;
438 	else if (status & SSFSTS_CTL_AEL)
439 		return -EACCES;
440 
441 	return 0;
442 }
443 
444 static int intel_spi_read_reg(struct intel_spi *ispi,
445 			      const struct intel_spi_mem_op *iop,
446 			      const struct spi_mem_op *op)
447 {
448 	size_t nbytes = op->data.nbytes;
449 	u8 opcode = op->cmd.opcode;
450 	int ret;
451 
452 	/* Address of the first chip */
453 	writel(0, ispi->base + FADDR);
454 
455 	if (ispi->swseq_reg)
456 		ret = intel_spi_sw_cycle(ispi, opcode, nbytes,
457 					 OPTYPE_READ_NO_ADDR);
458 	else
459 		ret = intel_spi_hw_cycle(ispi, opcode, nbytes);
460 
461 	if (ret)
462 		return ret;
463 
464 	return intel_spi_read_block(ispi, op->data.buf.in, nbytes);
465 }
466 
467 static int intel_spi_write_reg(struct intel_spi *ispi,
468 			       const struct intel_spi_mem_op *iop,
469 			       const struct spi_mem_op *op)
470 {
471 	size_t nbytes = op->data.nbytes;
472 	u8 opcode = op->cmd.opcode;
473 	int ret;
474 
475 	/*
476 	 * This is handled with atomic operation and preop code in Intel
477 	 * controller so we only verify that it is available. If the
478 	 * controller is not locked, program the opcode to the PREOP
479 	 * register for later use.
480 	 *
481 	 * When hardware sequencer is used there is no need to program
482 	 * any opcodes (it handles them automatically as part of a command).
483 	 */
484 	if (opcode == SPINOR_OP_WREN) {
485 		u16 preop;
486 
487 		if (!ispi->swseq_reg)
488 			return 0;
489 
490 		preop = readw(ispi->sregs + PREOP_OPTYPE);
491 		if ((preop & 0xff) != opcode && (preop >> 8) != opcode) {
492 			if (ispi->locked)
493 				return -EINVAL;
494 			writel(opcode, ispi->sregs + PREOP_OPTYPE);
495 		}
496 
497 		/*
498 		 * This enables atomic sequence on next SW sycle. Will
499 		 * be cleared after next operation.
500 		 */
501 		ispi->atomic_preopcode = opcode;
502 		return 0;
503 	}
504 
505 	/*
506 	 * We hope that HW sequencer will do the right thing automatically and
507 	 * with the SW sequencer we cannot use preopcode anyway, so just ignore
508 	 * the Write Disable operation and pretend it was completed
509 	 * successfully.
510 	 */
511 	if (opcode == SPINOR_OP_WRDI)
512 		return 0;
513 
514 	writel(0, ispi->base + FADDR);
515 
516 	/* Write the value beforehand */
517 	ret = intel_spi_write_block(ispi, op->data.buf.out, nbytes);
518 	if (ret)
519 		return ret;
520 
521 	if (ispi->swseq_reg)
522 		return intel_spi_sw_cycle(ispi, opcode, nbytes,
523 					  OPTYPE_WRITE_NO_ADDR);
524 	return intel_spi_hw_cycle(ispi, opcode, nbytes);
525 }
526 
527 static int intel_spi_read(struct intel_spi *ispi,
528 			  const struct intel_spi_mem_op *iop,
529 			  const struct spi_mem_op *op)
530 {
531 	void *read_buf = op->data.buf.in;
532 	size_t block_size, nbytes = op->data.nbytes;
533 	u32 addr = op->addr.val;
534 	u32 val, status;
535 	int ret;
536 
537 	/*
538 	 * Atomic sequence is not expected with HW sequencer reads. Make
539 	 * sure it is cleared regardless.
540 	 */
541 	if (WARN_ON_ONCE(ispi->atomic_preopcode))
542 		ispi->atomic_preopcode = 0;
543 
544 	while (nbytes > 0) {
545 		block_size = min_t(size_t, nbytes, INTEL_SPI_FIFO_SZ);
546 
547 		/* Read cannot cross 4K boundary */
548 		block_size = min_t(loff_t, addr + block_size,
549 				   round_up(addr + 1, SZ_4K)) - addr;
550 
551 		writel(addr, ispi->base + FADDR);
552 
553 		val = readl(ispi->base + HSFSTS_CTL);
554 		val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK);
555 		val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
556 		val |= (block_size - 1) << HSFSTS_CTL_FDBC_SHIFT;
557 		val |= HSFSTS_CTL_FCYCLE_READ;
558 		val |= HSFSTS_CTL_FGO;
559 		writel(val, ispi->base + HSFSTS_CTL);
560 
561 		ret = intel_spi_wait_hw_busy(ispi);
562 		if (ret)
563 			return ret;
564 
565 		status = readl(ispi->base + HSFSTS_CTL);
566 		if (status & HSFSTS_CTL_FCERR)
567 			ret = -EIO;
568 		else if (status & HSFSTS_CTL_AEL)
569 			ret = -EACCES;
570 
571 		if (ret < 0) {
572 			dev_err(ispi->dev, "read error: %x: %#x\n", addr, status);
573 			return ret;
574 		}
575 
576 		ret = intel_spi_read_block(ispi, read_buf, block_size);
577 		if (ret)
578 			return ret;
579 
580 		nbytes -= block_size;
581 		addr += block_size;
582 		read_buf += block_size;
583 	}
584 
585 	return 0;
586 }
587 
588 static int intel_spi_write(struct intel_spi *ispi,
589 			   const struct intel_spi_mem_op *iop,
590 			   const struct spi_mem_op *op)
591 {
592 	size_t block_size, nbytes = op->data.nbytes;
593 	const void *write_buf = op->data.buf.out;
594 	u32 addr = op->addr.val;
595 	u32 val, status;
596 	int ret;
597 
598 	/* Not needed with HW sequencer write, make sure it is cleared */
599 	ispi->atomic_preopcode = 0;
600 
601 	while (nbytes > 0) {
602 		block_size = min_t(size_t, nbytes, INTEL_SPI_FIFO_SZ);
603 
604 		/* Write cannot cross 4K boundary */
605 		block_size = min_t(loff_t, addr + block_size,
606 				   round_up(addr + 1, SZ_4K)) - addr;
607 
608 		writel(addr, ispi->base + FADDR);
609 
610 		val = readl(ispi->base + HSFSTS_CTL);
611 		val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK);
612 		val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
613 		val |= (block_size - 1) << HSFSTS_CTL_FDBC_SHIFT;
614 		val |= HSFSTS_CTL_FCYCLE_WRITE;
615 
616 		ret = intel_spi_write_block(ispi, write_buf, block_size);
617 		if (ret) {
618 			dev_err(ispi->dev, "failed to write block\n");
619 			return ret;
620 		}
621 
622 		/* Start the write now */
623 		val |= HSFSTS_CTL_FGO;
624 		writel(val, ispi->base + HSFSTS_CTL);
625 
626 		ret = intel_spi_wait_hw_busy(ispi);
627 		if (ret) {
628 			dev_err(ispi->dev, "timeout\n");
629 			return ret;
630 		}
631 
632 		status = readl(ispi->base + HSFSTS_CTL);
633 		if (status & HSFSTS_CTL_FCERR)
634 			ret = -EIO;
635 		else if (status & HSFSTS_CTL_AEL)
636 			ret = -EACCES;
637 
638 		if (ret < 0) {
639 			dev_err(ispi->dev, "write error: %x: %#x\n", addr, status);
640 			return ret;
641 		}
642 
643 		nbytes -= block_size;
644 		addr += block_size;
645 		write_buf += block_size;
646 	}
647 
648 	return 0;
649 }
650 
651 static int intel_spi_erase(struct intel_spi *ispi,
652 			   const struct intel_spi_mem_op *iop,
653 			   const struct spi_mem_op *op)
654 {
655 	u8 opcode = op->cmd.opcode;
656 	u32 addr = op->addr.val;
657 	u32 val, status;
658 	int ret;
659 
660 	writel(addr, ispi->base + FADDR);
661 
662 	if (ispi->swseq_erase)
663 		return intel_spi_sw_cycle(ispi, opcode, 0,
664 					  OPTYPE_WRITE_WITH_ADDR);
665 
666 	/* Not needed with HW sequencer erase, make sure it is cleared */
667 	ispi->atomic_preopcode = 0;
668 
669 	val = readl(ispi->base + HSFSTS_CTL);
670 	val &= ~(HSFSTS_CTL_FDBC_MASK | HSFSTS_CTL_FCYCLE_MASK);
671 	val |= HSFSTS_CTL_AEL | HSFSTS_CTL_FCERR | HSFSTS_CTL_FDONE;
672 	val |= HSFSTS_CTL_FGO;
673 	val |= iop->replacement_op;
674 	writel(val, ispi->base + HSFSTS_CTL);
675 
676 	ret = intel_spi_wait_hw_busy(ispi);
677 	if (ret)
678 		return ret;
679 
680 	status = readl(ispi->base + HSFSTS_CTL);
681 	if (status & HSFSTS_CTL_FCERR)
682 		return -EIO;
683 	if (status & HSFSTS_CTL_AEL)
684 		return -EACCES;
685 
686 	return 0;
687 }
688 
689 static bool intel_spi_cmp_mem_op(const struct intel_spi_mem_op *iop,
690 				 const struct spi_mem_op *op)
691 {
692 	if (iop->mem_op.cmd.nbytes != op->cmd.nbytes ||
693 	    iop->mem_op.cmd.buswidth != op->cmd.buswidth ||
694 	    iop->mem_op.cmd.dtr != op->cmd.dtr ||
695 	    iop->mem_op.cmd.opcode != op->cmd.opcode)
696 		return false;
697 
698 	if (iop->mem_op.addr.nbytes != op->addr.nbytes ||
699 	    iop->mem_op.addr.dtr != op->addr.dtr)
700 		return false;
701 
702 	if (iop->mem_op.data.dir != op->data.dir ||
703 	    iop->mem_op.data.dtr != op->data.dtr)
704 		return false;
705 
706 	if (iop->mem_op.data.dir != SPI_MEM_NO_DATA) {
707 		if (iop->mem_op.data.buswidth != op->data.buswidth)
708 			return false;
709 	}
710 
711 	return true;
712 }
713 
714 static const struct intel_spi_mem_op *
715 intel_spi_match_mem_op(struct intel_spi *ispi, const struct spi_mem_op *op)
716 {
717 	const struct intel_spi_mem_op *iop;
718 
719 	for (iop = ispi->mem_ops; iop->mem_op.cmd.opcode; iop++) {
720 		if (intel_spi_cmp_mem_op(iop, op))
721 			break;
722 	}
723 
724 	return iop->mem_op.cmd.opcode ? iop : NULL;
725 }
726 
727 static bool intel_spi_supports_mem_op(struct spi_mem *mem,
728 				      const struct spi_mem_op *op)
729 {
730 	struct intel_spi *ispi = spi_master_get_devdata(mem->spi->master);
731 	const struct intel_spi_mem_op *iop;
732 
733 	iop = intel_spi_match_mem_op(ispi, op);
734 	if (!iop) {
735 		dev_dbg(ispi->dev, "%#x not supported\n", op->cmd.opcode);
736 		return false;
737 	}
738 
739 	/*
740 	 * For software sequencer check that the opcode is actually
741 	 * present in the opmenu if it is locked.
742 	 */
743 	if (ispi->swseq_reg && ispi->locked) {
744 		int i;
745 
746 		/* Check if it is in the locked opcodes list */
747 		for (i = 0; i < ARRAY_SIZE(ispi->opcodes); i++) {
748 			if (ispi->opcodes[i] == op->cmd.opcode)
749 				return true;
750 		}
751 
752 		dev_dbg(ispi->dev, "%#x not supported\n", op->cmd.opcode);
753 		return false;
754 	}
755 
756 	return true;
757 }
758 
759 static int intel_spi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op)
760 {
761 	struct intel_spi *ispi = spi_master_get_devdata(mem->spi->master);
762 	const struct intel_spi_mem_op *iop;
763 
764 	iop = intel_spi_match_mem_op(ispi, op);
765 	if (!iop)
766 		return -EOPNOTSUPP;
767 
768 	return iop->exec_op(ispi, iop, op);
769 }
770 
771 static const char *intel_spi_get_name(struct spi_mem *mem)
772 {
773 	const struct intel_spi *ispi = spi_master_get_devdata(mem->spi->master);
774 
775 	/*
776 	 * Return name of the flash controller device to be compatible
777 	 * with the MTD version.
778 	 */
779 	return dev_name(ispi->dev);
780 }
781 
782 static int intel_spi_dirmap_create(struct spi_mem_dirmap_desc *desc)
783 {
784 	struct intel_spi *ispi = spi_master_get_devdata(desc->mem->spi->master);
785 	const struct intel_spi_mem_op *iop;
786 
787 	iop = intel_spi_match_mem_op(ispi, &desc->info.op_tmpl);
788 	if (!iop)
789 		return -EOPNOTSUPP;
790 
791 	desc->priv = (void *)iop;
792 	return 0;
793 }
794 
795 static ssize_t intel_spi_dirmap_read(struct spi_mem_dirmap_desc *desc, u64 offs,
796 				     size_t len, void *buf)
797 {
798 	struct intel_spi *ispi = spi_master_get_devdata(desc->mem->spi->master);
799 	const struct intel_spi_mem_op *iop = desc->priv;
800 	struct spi_mem_op op = desc->info.op_tmpl;
801 	int ret;
802 
803 	/* Fill in the gaps */
804 	op.addr.val = offs;
805 	op.data.nbytes = len;
806 	op.data.buf.in = buf;
807 
808 	ret = iop->exec_op(ispi, iop, &op);
809 	return ret ? ret : len;
810 }
811 
812 static ssize_t intel_spi_dirmap_write(struct spi_mem_dirmap_desc *desc, u64 offs,
813 				      size_t len, const void *buf)
814 {
815 	struct intel_spi *ispi = spi_master_get_devdata(desc->mem->spi->master);
816 	const struct intel_spi_mem_op *iop = desc->priv;
817 	struct spi_mem_op op = desc->info.op_tmpl;
818 	int ret;
819 
820 	op.addr.val = offs;
821 	op.data.nbytes = len;
822 	op.data.buf.out = buf;
823 
824 	ret = iop->exec_op(ispi, iop, &op);
825 	return ret ? ret : len;
826 }
827 
828 static const struct spi_controller_mem_ops intel_spi_mem_ops = {
829 	.supports_op = intel_spi_supports_mem_op,
830 	.exec_op = intel_spi_exec_mem_op,
831 	.get_name = intel_spi_get_name,
832 	.dirmap_create = intel_spi_dirmap_create,
833 	.dirmap_read = intel_spi_dirmap_read,
834 	.dirmap_write = intel_spi_dirmap_write,
835 };
836 
837 #define INTEL_SPI_OP_ADDR(__nbytes)					\
838 	{								\
839 		.nbytes = __nbytes,					\
840 	}
841 
842 #define INTEL_SPI_OP_NO_DATA						\
843 	{								\
844 		.dir = SPI_MEM_NO_DATA,					\
845 	}
846 
847 #define INTEL_SPI_OP_DATA_IN(__buswidth)				\
848 	{								\
849 		.dir = SPI_MEM_DATA_IN,					\
850 		.buswidth = __buswidth,					\
851 	}
852 
853 #define INTEL_SPI_OP_DATA_OUT(__buswidth)				\
854 	{								\
855 		.dir = SPI_MEM_DATA_OUT,				\
856 		.buswidth = __buswidth,					\
857 	}
858 
859 #define INTEL_SPI_MEM_OP(__cmd, __addr, __data, __exec_op)		\
860 	{								\
861 		.mem_op = {						\
862 			.cmd = __cmd,					\
863 			.addr = __addr,					\
864 			.data = __data,					\
865 		},							\
866 		.exec_op = __exec_op,					\
867 	}
868 
869 #define INTEL_SPI_MEM_OP_REPL(__cmd, __addr, __data, __exec_op, __repl)	\
870 	{								\
871 		.mem_op = {						\
872 			.cmd = __cmd,					\
873 			.addr = __addr,					\
874 			.data = __data,					\
875 		},							\
876 		.exec_op = __exec_op,					\
877 		.replacement_op = __repl,				\
878 	}
879 
880 /*
881  * The controller handles pretty much everything internally based on the
882  * SFDP data but we want to make sure we only support the operations
883  * actually possible. Only check buswidth and transfer direction, the
884  * core validates data.
885  */
886 #define INTEL_SPI_GENERIC_OPS						\
887 	/* Status register operations */				\
888 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDID, 1),		\
889 			 SPI_MEM_OP_NO_ADDR,				\
890 			 INTEL_SPI_OP_DATA_IN(1),			\
891 			 intel_spi_read_reg),				\
892 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR, 1),		\
893 			 SPI_MEM_OP_NO_ADDR,				\
894 			 INTEL_SPI_OP_DATA_IN(1),			\
895 			 intel_spi_read_reg),				\
896 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR, 1),		\
897 			 SPI_MEM_OP_NO_ADDR,				\
898 			 INTEL_SPI_OP_DATA_OUT(1),			\
899 			 intel_spi_write_reg),				\
900 	/* Normal read */						\
901 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
902 			 INTEL_SPI_OP_ADDR(3),				\
903 			 INTEL_SPI_OP_DATA_IN(1),			\
904 			 intel_spi_read),				\
905 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
906 			 INTEL_SPI_OP_ADDR(3),				\
907 			 INTEL_SPI_OP_DATA_IN(2),			\
908 			 intel_spi_read),				\
909 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
910 			 INTEL_SPI_OP_ADDR(3),				\
911 			 INTEL_SPI_OP_DATA_IN(4),			\
912 			 intel_spi_read),				\
913 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
914 			 INTEL_SPI_OP_ADDR(4),				\
915 			 INTEL_SPI_OP_DATA_IN(1),			\
916 			 intel_spi_read),				\
917 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
918 			 INTEL_SPI_OP_ADDR(4),				\
919 			 INTEL_SPI_OP_DATA_IN(2),			\
920 			 intel_spi_read),				\
921 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ, 1),		\
922 			 INTEL_SPI_OP_ADDR(4),				\
923 			 INTEL_SPI_OP_DATA_IN(4),			\
924 			 intel_spi_read),				\
925 	/* Fast read */							\
926 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
927 			 INTEL_SPI_OP_ADDR(3),				\
928 			 INTEL_SPI_OP_DATA_IN(1),			\
929 			 intel_spi_read),				\
930 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
931 			 INTEL_SPI_OP_ADDR(3),				\
932 			 INTEL_SPI_OP_DATA_IN(2),			\
933 			 intel_spi_read),				\
934 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
935 			 INTEL_SPI_OP_ADDR(3),				\
936 			 INTEL_SPI_OP_DATA_IN(4),			\
937 			 intel_spi_read),				\
938 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
939 			 INTEL_SPI_OP_ADDR(4),				\
940 			 INTEL_SPI_OP_DATA_IN(1),			\
941 			 intel_spi_read),				\
942 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
943 			 INTEL_SPI_OP_ADDR(4),				\
944 			 INTEL_SPI_OP_DATA_IN(2),			\
945 			 intel_spi_read),				\
946 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST, 1),	\
947 			 INTEL_SPI_OP_ADDR(4),				\
948 			 INTEL_SPI_OP_DATA_IN(4),			\
949 			 intel_spi_read),				\
950 	/* Read with 4-byte address opcode */				\
951 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_4B, 1),		\
952 			 INTEL_SPI_OP_ADDR(4),				\
953 			 INTEL_SPI_OP_DATA_IN(1),			\
954 			 intel_spi_read),				\
955 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_4B, 1),		\
956 			 INTEL_SPI_OP_ADDR(4),				\
957 			 INTEL_SPI_OP_DATA_IN(2),			\
958 			 intel_spi_read),				\
959 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_4B, 1),		\
960 			 INTEL_SPI_OP_ADDR(4),				\
961 			 INTEL_SPI_OP_DATA_IN(4),			\
962 			 intel_spi_read),				\
963 	/* Fast read with 4-byte address opcode */			\
964 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST_4B, 1),	\
965 			 INTEL_SPI_OP_ADDR(4),				\
966 			 INTEL_SPI_OP_DATA_IN(1),			\
967 			 intel_spi_read),				\
968 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST_4B, 1),	\
969 			 INTEL_SPI_OP_ADDR(4),				\
970 			 INTEL_SPI_OP_DATA_IN(2),			\
971 			 intel_spi_read),				\
972 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_READ_FAST_4B, 1),	\
973 			 INTEL_SPI_OP_ADDR(4),				\
974 			 INTEL_SPI_OP_DATA_IN(4),			\
975 			 intel_spi_read),				\
976 	/* Write operations */						\
977 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_PP, 1),		\
978 			 INTEL_SPI_OP_ADDR(3),				\
979 			 INTEL_SPI_OP_DATA_OUT(1),			\
980 			 intel_spi_write),				\
981 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_PP, 1),		\
982 			 INTEL_SPI_OP_ADDR(4),				\
983 			 INTEL_SPI_OP_DATA_OUT(1),			\
984 			 intel_spi_write),				\
985 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_PP_4B, 1),		\
986 			 INTEL_SPI_OP_ADDR(4),				\
987 			 INTEL_SPI_OP_DATA_OUT(1),			\
988 			 intel_spi_write),				\
989 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WREN, 1),		\
990 			 SPI_MEM_OP_NO_ADDR,				\
991 			 SPI_MEM_OP_NO_DATA,				\
992 			 intel_spi_write_reg),				\
993 	INTEL_SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRDI, 1),		\
994 			 SPI_MEM_OP_NO_ADDR,				\
995 			 SPI_MEM_OP_NO_DATA,				\
996 			 intel_spi_write_reg),				\
997 	/* Erase operations */						\
998 	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_BE_4K, 1),	\
999 			      INTEL_SPI_OP_ADDR(3),			\
1000 			      SPI_MEM_OP_NO_DATA,			\
1001 			      intel_spi_erase,				\
1002 			      HSFSTS_CTL_FCYCLE_ERASE),			\
1003 	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_BE_4K, 1),	\
1004 			      INTEL_SPI_OP_ADDR(4),			\
1005 			      SPI_MEM_OP_NO_DATA,			\
1006 			      intel_spi_erase,				\
1007 			      HSFSTS_CTL_FCYCLE_ERASE),			\
1008 	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_BE_4K_4B, 1),	\
1009 			      INTEL_SPI_OP_ADDR(4),			\
1010 			      SPI_MEM_OP_NO_DATA,			\
1011 			      intel_spi_erase,				\
1012 			      HSFSTS_CTL_FCYCLE_ERASE)			\
1013 
1014 static const struct intel_spi_mem_op generic_mem_ops[] = {
1015 	INTEL_SPI_GENERIC_OPS,
1016 	{ },
1017 };
1018 
1019 static const struct intel_spi_mem_op erase_64k_mem_ops[] = {
1020 	INTEL_SPI_GENERIC_OPS,
1021 	/* 64k sector erase operations */
1022 	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_SE, 1),
1023 			      INTEL_SPI_OP_ADDR(3),
1024 			      SPI_MEM_OP_NO_DATA,
1025 			      intel_spi_erase,
1026 			      HSFSTS_CTL_FCYCLE_ERASE_64K),
1027 	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_SE, 1),
1028 			      INTEL_SPI_OP_ADDR(4),
1029 			      SPI_MEM_OP_NO_DATA,
1030 			      intel_spi_erase,
1031 			      HSFSTS_CTL_FCYCLE_ERASE_64K),
1032 	INTEL_SPI_MEM_OP_REPL(SPI_MEM_OP_CMD(SPINOR_OP_SE_4B, 1),
1033 			      INTEL_SPI_OP_ADDR(4),
1034 			      SPI_MEM_OP_NO_DATA,
1035 			      intel_spi_erase,
1036 			      HSFSTS_CTL_FCYCLE_ERASE_64K),
1037 	{ },
1038 };
1039 
1040 static int intel_spi_init(struct intel_spi *ispi)
1041 {
1042 	u32 opmenu0, opmenu1, lvscc, uvscc, val;
1043 	bool erase_64k = false;
1044 	int i;
1045 
1046 	switch (ispi->info->type) {
1047 	case INTEL_SPI_BYT:
1048 		ispi->sregs = ispi->base + BYT_SSFSTS_CTL;
1049 		ispi->pregs = ispi->base + BYT_PR;
1050 		ispi->nregions = BYT_FREG_NUM;
1051 		ispi->pr_num = BYT_PR_NUM;
1052 		ispi->swseq_reg = true;
1053 		break;
1054 
1055 	case INTEL_SPI_LPT:
1056 		ispi->sregs = ispi->base + LPT_SSFSTS_CTL;
1057 		ispi->pregs = ispi->base + LPT_PR;
1058 		ispi->nregions = LPT_FREG_NUM;
1059 		ispi->pr_num = LPT_PR_NUM;
1060 		ispi->swseq_reg = true;
1061 		break;
1062 
1063 	case INTEL_SPI_BXT:
1064 		ispi->sregs = ispi->base + BXT_SSFSTS_CTL;
1065 		ispi->pregs = ispi->base + BXT_PR;
1066 		ispi->nregions = BXT_FREG_NUM;
1067 		ispi->pr_num = BXT_PR_NUM;
1068 		erase_64k = true;
1069 		break;
1070 
1071 	case INTEL_SPI_CNL:
1072 		ispi->sregs = NULL;
1073 		ispi->pregs = ispi->base + CNL_PR;
1074 		ispi->nregions = CNL_FREG_NUM;
1075 		ispi->pr_num = CNL_PR_NUM;
1076 		break;
1077 
1078 	default:
1079 		return -EINVAL;
1080 	}
1081 
1082 	/* Try to disable write protection if user asked to do so */
1083 	if (writeable && !intel_spi_set_writeable(ispi)) {
1084 		dev_warn(ispi->dev, "can't disable chip write protection\n");
1085 		writeable = false;
1086 	}
1087 
1088 	/* Disable #SMI generation from HW sequencer */
1089 	val = readl(ispi->base + HSFSTS_CTL);
1090 	val &= ~HSFSTS_CTL_FSMIE;
1091 	writel(val, ispi->base + HSFSTS_CTL);
1092 
1093 	/*
1094 	 * Determine whether erase operation should use HW or SW sequencer.
1095 	 *
1096 	 * The HW sequencer has a predefined list of opcodes, with only the
1097 	 * erase opcode being programmable in LVSCC and UVSCC registers.
1098 	 * If these registers don't contain a valid erase opcode, erase
1099 	 * cannot be done using HW sequencer.
1100 	 */
1101 	lvscc = readl(ispi->base + LVSCC);
1102 	uvscc = readl(ispi->base + UVSCC);
1103 	if (!(lvscc & ERASE_OPCODE_MASK) || !(uvscc & ERASE_OPCODE_MASK))
1104 		ispi->swseq_erase = true;
1105 	/* SPI controller on Intel BXT supports 64K erase opcode */
1106 	if (ispi->info->type == INTEL_SPI_BXT && !ispi->swseq_erase)
1107 		if (!(lvscc & ERASE_64K_OPCODE_MASK) ||
1108 		    !(uvscc & ERASE_64K_OPCODE_MASK))
1109 			erase_64k = false;
1110 
1111 	if (!ispi->sregs && (ispi->swseq_reg || ispi->swseq_erase)) {
1112 		dev_err(ispi->dev, "software sequencer not supported, but required\n");
1113 		return -EINVAL;
1114 	}
1115 
1116 	/*
1117 	 * Some controllers can only do basic operations using hardware
1118 	 * sequencer. All other operations are supposed to be carried out
1119 	 * using software sequencer.
1120 	 */
1121 	if (ispi->swseq_reg) {
1122 		/* Disable #SMI generation from SW sequencer */
1123 		val = readl(ispi->sregs + SSFSTS_CTL);
1124 		val &= ~SSFSTS_CTL_FSMIE;
1125 		writel(val, ispi->sregs + SSFSTS_CTL);
1126 	}
1127 
1128 	/* Check controller's lock status */
1129 	val = readl(ispi->base + HSFSTS_CTL);
1130 	ispi->locked = !!(val & HSFSTS_CTL_FLOCKDN);
1131 
1132 	if (ispi->locked && ispi->sregs) {
1133 		/*
1134 		 * BIOS programs allowed opcodes and then locks down the
1135 		 * register. So read back what opcodes it decided to support.
1136 		 * That's the set we are going to support as well.
1137 		 */
1138 		opmenu0 = readl(ispi->sregs + OPMENU0);
1139 		opmenu1 = readl(ispi->sregs + OPMENU1);
1140 
1141 		if (opmenu0 && opmenu1) {
1142 			for (i = 0; i < ARRAY_SIZE(ispi->opcodes) / 2; i++) {
1143 				ispi->opcodes[i] = opmenu0 >> i * 8;
1144 				ispi->opcodes[i + 4] = opmenu1 >> i * 8;
1145 			}
1146 		}
1147 	}
1148 
1149 	if (erase_64k) {
1150 		dev_dbg(ispi->dev, "Using erase_64k memory operations");
1151 		ispi->mem_ops = erase_64k_mem_ops;
1152 	} else {
1153 		dev_dbg(ispi->dev, "Using generic memory operations");
1154 		ispi->mem_ops = generic_mem_ops;
1155 	}
1156 
1157 	intel_spi_dump_regs(ispi);
1158 	return 0;
1159 }
1160 
1161 static bool intel_spi_is_protected(const struct intel_spi *ispi,
1162 				   unsigned int base, unsigned int limit)
1163 {
1164 	int i;
1165 
1166 	for (i = 0; i < ispi->pr_num; i++) {
1167 		u32 pr_base, pr_limit, pr_value;
1168 
1169 		pr_value = readl(ispi->pregs + PR(i));
1170 		if (!(pr_value & (PR_WPE | PR_RPE)))
1171 			continue;
1172 
1173 		pr_limit = (pr_value & PR_LIMIT_MASK) >> PR_LIMIT_SHIFT;
1174 		pr_base = pr_value & PR_BASE_MASK;
1175 
1176 		if (pr_base >= base && pr_limit <= limit)
1177 			return true;
1178 	}
1179 
1180 	return false;
1181 }
1182 
1183 /*
1184  * There will be a single partition holding all enabled flash regions. We
1185  * call this "BIOS".
1186  */
1187 static void intel_spi_fill_partition(struct intel_spi *ispi,
1188 				     struct mtd_partition *part)
1189 {
1190 	u64 end;
1191 	int i;
1192 
1193 	memset(part, 0, sizeof(*part));
1194 
1195 	/* Start from the mandatory descriptor region */
1196 	part->size = 4096;
1197 	part->name = "BIOS";
1198 
1199 	/*
1200 	 * Now try to find where this partition ends based on the flash
1201 	 * region registers.
1202 	 */
1203 	for (i = 1; i < ispi->nregions; i++) {
1204 		u32 region, base, limit;
1205 
1206 		region = readl(ispi->base + FREG(i));
1207 		base = region & FREG_BASE_MASK;
1208 		limit = (region & FREG_LIMIT_MASK) >> FREG_LIMIT_SHIFT;
1209 
1210 		if (base >= limit || limit == 0)
1211 			continue;
1212 
1213 		/*
1214 		 * If any of the regions have protection bits set, make the
1215 		 * whole partition read-only to be on the safe side.
1216 		 *
1217 		 * Also if the user did not ask the chip to be writeable
1218 		 * mask the bit too.
1219 		 */
1220 		if (!writeable || intel_spi_is_protected(ispi, base, limit))
1221 			part->mask_flags |= MTD_WRITEABLE;
1222 
1223 		end = (limit << 12) + 4096;
1224 		if (end > part->size)
1225 			part->size = end;
1226 	}
1227 }
1228 
1229 static int intel_spi_populate_chip(struct intel_spi *ispi)
1230 {
1231 	struct flash_platform_data *pdata;
1232 	struct spi_board_info chip;
1233 
1234 	pdata = devm_kzalloc(ispi->dev, sizeof(*pdata), GFP_KERNEL);
1235 	if (!pdata)
1236 		return -ENOMEM;
1237 
1238 	pdata->nr_parts = 1;
1239 	pdata->parts = devm_kcalloc(ispi->dev, pdata->nr_parts,
1240 				    sizeof(*pdata->parts), GFP_KERNEL);
1241 	if (!pdata->parts)
1242 		return -ENOMEM;
1243 
1244 	intel_spi_fill_partition(ispi, pdata->parts);
1245 
1246 	memset(&chip, 0, sizeof(chip));
1247 	snprintf(chip.modalias, 8, "spi-nor");
1248 	chip.platform_data = pdata;
1249 
1250 	return spi_new_device(ispi->master, &chip) ? 0 : -ENODEV;
1251 }
1252 
1253 /**
1254  * intel_spi_probe() - Probe the Intel SPI flash controller
1255  * @dev: Pointer to the parent device
1256  * @mem: MMIO resource
1257  * @info: Platform specific information
1258  *
1259  * Probes Intel SPI flash controller and creates the flash chip device.
1260  * Returns %0 on success and negative errno in case of failure.
1261  */
1262 int intel_spi_probe(struct device *dev, struct resource *mem,
1263 		    const struct intel_spi_boardinfo *info)
1264 {
1265 	struct spi_controller *master;
1266 	struct intel_spi *ispi;
1267 	int ret;
1268 
1269 	master = devm_spi_alloc_master(dev, sizeof(*ispi));
1270 	if (!master)
1271 		return -ENOMEM;
1272 
1273 	master->mem_ops = &intel_spi_mem_ops;
1274 
1275 	ispi = spi_master_get_devdata(master);
1276 
1277 	ispi->base = devm_ioremap_resource(dev, mem);
1278 	if (IS_ERR(ispi->base))
1279 		return PTR_ERR(ispi->base);
1280 
1281 	ispi->dev = dev;
1282 	ispi->master = master;
1283 	ispi->info = info;
1284 
1285 	ret = intel_spi_init(ispi);
1286 	if (ret)
1287 		return ret;
1288 
1289 	ret = devm_spi_register_master(dev, master);
1290 	if (ret)
1291 		return ret;
1292 
1293 	return intel_spi_populate_chip(ispi);
1294 }
1295 EXPORT_SYMBOL_GPL(intel_spi_probe);
1296 
1297 MODULE_DESCRIPTION("Intel PCH/PCU SPI flash core driver");
1298 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
1299 MODULE_LICENSE("GPL v2");
1300