xref: /openbmc/linux/drivers/mtd/devices/st_spi_fsm.c (revision afb46f79)
1 /*
2  * st_spi_fsm.c	- ST Fast Sequence Mode (FSM) Serial Flash Controller
3  *
4  * Author: Angus Clark <angus.clark@st.com>
5  *
6  * Copyright (C) 2010-2014 STMicroelectronics Limited
7  *
8  * JEDEC probe based on drivers/mtd/devices/m25p80.c
9  *
10  * This code is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  *
14  */
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/regmap.h>
18 #include <linux/platform_device.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/sched.h>
23 #include <linux/delay.h>
24 #include <linux/io.h>
25 #include <linux/of.h>
26 
27 #include "serial_flash_cmds.h"
28 
29 /*
30  * FSM SPI Controller Registers
31  */
32 #define SPI_CLOCKDIV			0x0010
33 #define SPI_MODESELECT			0x0018
34 #define SPI_CONFIGDATA			0x0020
35 #define SPI_STA_MODE_CHANGE		0x0028
36 #define SPI_FAST_SEQ_TRANSFER_SIZE	0x0100
37 #define SPI_FAST_SEQ_ADD1		0x0104
38 #define SPI_FAST_SEQ_ADD2		0x0108
39 #define SPI_FAST_SEQ_ADD_CFG		0x010c
40 #define SPI_FAST_SEQ_OPC1		0x0110
41 #define SPI_FAST_SEQ_OPC2		0x0114
42 #define SPI_FAST_SEQ_OPC3		0x0118
43 #define SPI_FAST_SEQ_OPC4		0x011c
44 #define SPI_FAST_SEQ_OPC5		0x0120
45 #define SPI_MODE_BITS			0x0124
46 #define SPI_DUMMY_BITS			0x0128
47 #define SPI_FAST_SEQ_FLASH_STA_DATA	0x012c
48 #define SPI_FAST_SEQ_1			0x0130
49 #define SPI_FAST_SEQ_2			0x0134
50 #define SPI_FAST_SEQ_3			0x0138
51 #define SPI_FAST_SEQ_4			0x013c
52 #define SPI_FAST_SEQ_CFG		0x0140
53 #define SPI_FAST_SEQ_STA		0x0144
54 #define SPI_QUAD_BOOT_SEQ_INIT_1	0x0148
55 #define SPI_QUAD_BOOT_SEQ_INIT_2	0x014c
56 #define SPI_QUAD_BOOT_READ_SEQ_1	0x0150
57 #define SPI_QUAD_BOOT_READ_SEQ_2	0x0154
58 #define SPI_PROGRAM_ERASE_TIME		0x0158
59 #define SPI_MULT_PAGE_REPEAT_SEQ_1	0x015c
60 #define SPI_MULT_PAGE_REPEAT_SEQ_2	0x0160
61 #define SPI_STATUS_WR_TIME_REG		0x0164
62 #define SPI_FAST_SEQ_DATA_REG		0x0300
63 
64 /*
65  * Register: SPI_MODESELECT
66  */
67 #define SPI_MODESELECT_CONTIG		0x01
68 #define SPI_MODESELECT_FASTREAD		0x02
69 #define SPI_MODESELECT_DUALIO		0x04
70 #define SPI_MODESELECT_FSM		0x08
71 #define SPI_MODESELECT_QUADBOOT		0x10
72 
73 /*
74  * Register: SPI_CONFIGDATA
75  */
76 #define SPI_CFG_DEVICE_ST		0x1
77 #define SPI_CFG_DEVICE_ATMEL		0x4
78 #define SPI_CFG_MIN_CS_HIGH(x)		(((x) & 0xfff) << 4)
79 #define SPI_CFG_CS_SETUPHOLD(x)		(((x) & 0xff) << 16)
80 #define SPI_CFG_DATA_HOLD(x)		(((x) & 0xff) << 24)
81 
82 #define SPI_CFG_DEFAULT_MIN_CS_HIGH    SPI_CFG_MIN_CS_HIGH(0x0AA)
83 #define SPI_CFG_DEFAULT_CS_SETUPHOLD   SPI_CFG_CS_SETUPHOLD(0xA0)
84 #define SPI_CFG_DEFAULT_DATA_HOLD      SPI_CFG_DATA_HOLD(0x00)
85 
86 /*
87  * Register: SPI_FAST_SEQ_TRANSFER_SIZE
88  */
89 #define TRANSFER_SIZE(x)		((x) * 8)
90 
91 /*
92  * Register: SPI_FAST_SEQ_ADD_CFG
93  */
94 #define ADR_CFG_CYCLES_ADD1(x)		((x) << 0)
95 #define ADR_CFG_PADS_1_ADD1		(0x0 << 6)
96 #define ADR_CFG_PADS_2_ADD1		(0x1 << 6)
97 #define ADR_CFG_PADS_4_ADD1		(0x3 << 6)
98 #define ADR_CFG_CSDEASSERT_ADD1		(1   << 8)
99 #define ADR_CFG_CYCLES_ADD2(x)		((x) << (0+16))
100 #define ADR_CFG_PADS_1_ADD2		(0x0 << (6+16))
101 #define ADR_CFG_PADS_2_ADD2		(0x1 << (6+16))
102 #define ADR_CFG_PADS_4_ADD2		(0x3 << (6+16))
103 #define ADR_CFG_CSDEASSERT_ADD2		(1   << (8+16))
104 
105 /*
106  * Register: SPI_FAST_SEQ_n
107  */
108 #define SEQ_OPC_OPCODE(x)		((x) << 0)
109 #define SEQ_OPC_CYCLES(x)		((x) << 8)
110 #define SEQ_OPC_PADS_1			(0x0 << 14)
111 #define SEQ_OPC_PADS_2			(0x1 << 14)
112 #define SEQ_OPC_PADS_4			(0x3 << 14)
113 #define SEQ_OPC_CSDEASSERT		(1   << 16)
114 
115 /*
116  * Register: SPI_FAST_SEQ_CFG
117  */
118 #define SEQ_CFG_STARTSEQ		(1 << 0)
119 #define SEQ_CFG_SWRESET			(1 << 5)
120 #define SEQ_CFG_CSDEASSERT		(1 << 6)
121 #define SEQ_CFG_READNOTWRITE		(1 << 7)
122 #define SEQ_CFG_ERASE			(1 << 8)
123 #define SEQ_CFG_PADS_1			(0x0 << 16)
124 #define SEQ_CFG_PADS_2			(0x1 << 16)
125 #define SEQ_CFG_PADS_4			(0x3 << 16)
126 
127 /*
128  * Register: SPI_MODE_BITS
129  */
130 #define MODE_DATA(x)			(x & 0xff)
131 #define MODE_CYCLES(x)			((x & 0x3f) << 16)
132 #define MODE_PADS_1			(0x0 << 22)
133 #define MODE_PADS_2			(0x1 << 22)
134 #define MODE_PADS_4			(0x3 << 22)
135 #define DUMMY_CSDEASSERT		(1   << 24)
136 
137 /*
138  * Register: SPI_DUMMY_BITS
139  */
140 #define DUMMY_CYCLES(x)			((x & 0x3f) << 16)
141 #define DUMMY_PADS_1			(0x0 << 22)
142 #define DUMMY_PADS_2			(0x1 << 22)
143 #define DUMMY_PADS_4			(0x3 << 22)
144 #define DUMMY_CSDEASSERT		(1   << 24)
145 
146 /*
147  * Register: SPI_FAST_SEQ_FLASH_STA_DATA
148  */
149 #define STA_DATA_BYTE1(x)		((x & 0xff) << 0)
150 #define STA_DATA_BYTE2(x)		((x & 0xff) << 8)
151 #define STA_PADS_1			(0x0 << 16)
152 #define STA_PADS_2			(0x1 << 16)
153 #define STA_PADS_4			(0x3 << 16)
154 #define STA_CSDEASSERT			(0x1 << 20)
155 #define STA_RDNOTWR			(0x1 << 21)
156 
157 /*
158  * FSM SPI Instruction Opcodes
159  */
160 #define STFSM_OPC_CMD			0x1
161 #define STFSM_OPC_ADD			0x2
162 #define STFSM_OPC_STA			0x3
163 #define STFSM_OPC_MODE			0x4
164 #define STFSM_OPC_DUMMY		0x5
165 #define STFSM_OPC_DATA			0x6
166 #define STFSM_OPC_WAIT			0x7
167 #define STFSM_OPC_JUMP			0x8
168 #define STFSM_OPC_GOTO			0x9
169 #define STFSM_OPC_STOP			0xF
170 
171 /*
172  * FSM SPI Instructions (== opcode + operand).
173  */
174 #define STFSM_INSTR(cmd, op)		((cmd) | ((op) << 4))
175 
176 #define STFSM_INST_CMD1			STFSM_INSTR(STFSM_OPC_CMD,	1)
177 #define STFSM_INST_CMD2			STFSM_INSTR(STFSM_OPC_CMD,	2)
178 #define STFSM_INST_CMD3			STFSM_INSTR(STFSM_OPC_CMD,	3)
179 #define STFSM_INST_CMD4			STFSM_INSTR(STFSM_OPC_CMD,	4)
180 #define STFSM_INST_CMD5			STFSM_INSTR(STFSM_OPC_CMD,	5)
181 #define STFSM_INST_ADD1			STFSM_INSTR(STFSM_OPC_ADD,	1)
182 #define STFSM_INST_ADD2			STFSM_INSTR(STFSM_OPC_ADD,	2)
183 
184 #define STFSM_INST_DATA_WRITE		STFSM_INSTR(STFSM_OPC_DATA,	1)
185 #define STFSM_INST_DATA_READ		STFSM_INSTR(STFSM_OPC_DATA,	2)
186 
187 #define STFSM_INST_STA_RD1		STFSM_INSTR(STFSM_OPC_STA,	0x1)
188 #define STFSM_INST_STA_WR1		STFSM_INSTR(STFSM_OPC_STA,	0x1)
189 #define STFSM_INST_STA_RD2		STFSM_INSTR(STFSM_OPC_STA,	0x2)
190 #define STFSM_INST_STA_WR1_2		STFSM_INSTR(STFSM_OPC_STA,	0x3)
191 
192 #define STFSM_INST_MODE			STFSM_INSTR(STFSM_OPC_MODE,	0)
193 #define STFSM_INST_DUMMY		STFSM_INSTR(STFSM_OPC_DUMMY,	0)
194 #define STFSM_INST_WAIT			STFSM_INSTR(STFSM_OPC_WAIT,	0)
195 #define STFSM_INST_STOP			STFSM_INSTR(STFSM_OPC_STOP,	0)
196 
197 #define STFSM_DEFAULT_EMI_FREQ 100000000UL                        /* 100 MHz */
198 #define STFSM_DEFAULT_WR_TIME  (STFSM_DEFAULT_EMI_FREQ * (15/1000)) /* 15ms */
199 
200 #define STFSM_FLASH_SAFE_FREQ  10000000UL                         /* 10 MHz */
201 
202 #define STFSM_MAX_WAIT_SEQ_MS  1000     /* FSM execution time */
203 
204 /* Flash Commands */
205 #define FLASH_CMD_WREN         0x06
206 #define FLASH_CMD_WRDI         0x04
207 #define FLASH_CMD_RDID         0x9f
208 #define FLASH_CMD_RDSR         0x05
209 #define FLASH_CMD_RDSR2                0x35
210 #define FLASH_CMD_WRSR         0x01
211 #define FLASH_CMD_SE_4K                0x20
212 #define FLASH_CMD_SE_32K       0x52
213 #define FLASH_CMD_SE           0xd8
214 #define FLASH_CMD_CHIPERASE    0xc7
215 #define FLASH_CMD_WRVCR                0x81
216 #define FLASH_CMD_RDVCR                0x85
217 
218 #define FLASH_CMD_READ         0x03    /* READ */
219 #define FLASH_CMD_READ_FAST    0x0b    /* FAST READ */
220 #define FLASH_CMD_READ_1_1_2   0x3b    /* DUAL OUTPUT READ */
221 #define FLASH_CMD_READ_1_2_2   0xbb    /* DUAL I/O READ */
222 #define FLASH_CMD_READ_1_1_4   0x6b    /* QUAD OUTPUT READ */
223 #define FLASH_CMD_READ_1_4_4   0xeb    /* QUAD I/O READ */
224 
225 #define FLASH_CMD_WRITE                0x02    /* PAGE PROGRAM */
226 #define FLASH_CMD_WRITE_1_1_2  0xa2    /* DUAL INPUT PROGRAM */
227 #define FLASH_CMD_WRITE_1_2_2  0xd2    /* DUAL INPUT EXT PROGRAM */
228 #define FLASH_CMD_WRITE_1_1_4  0x32    /* QUAD INPUT PROGRAM */
229 #define FLASH_CMD_WRITE_1_4_4  0x12    /* QUAD INPUT EXT PROGRAM */
230 
231 #define FLASH_CMD_EN4B_ADDR    0xb7    /* Enter 4-byte address mode */
232 #define FLASH_CMD_EX4B_ADDR    0xe9    /* Exit 4-byte address mode */
233 
234 /* READ commands with 32-bit addressing (N25Q256 and S25FLxxxS) */
235 #define FLASH_CMD_READ4                0x13
236 #define FLASH_CMD_READ4_FAST   0x0c
237 #define FLASH_CMD_READ4_1_1_2  0x3c
238 #define FLASH_CMD_READ4_1_2_2  0xbc
239 #define FLASH_CMD_READ4_1_1_4  0x6c
240 #define FLASH_CMD_READ4_1_4_4  0xec
241 
242 /* S25FLxxxS commands */
243 #define S25FL_CMD_WRITE4_1_1_4 0x34
244 #define S25FL_CMD_SE4          0xdc
245 #define S25FL_CMD_CLSR         0x30
246 #define S25FL_CMD_DYBWR                0xe1
247 #define S25FL_CMD_DYBRD                0xe0
248 #define S25FL_CMD_WRITE4       0x12    /* Note, opcode clashes with
249 					* 'FLASH_CMD_WRITE_1_4_4'
250 					* as found on N25Qxxx devices! */
251 
252 /* Status register */
253 #define FLASH_STATUS_BUSY      0x01
254 #define FLASH_STATUS_WEL       0x02
255 #define FLASH_STATUS_BP0       0x04
256 #define FLASH_STATUS_BP1       0x08
257 #define FLASH_STATUS_BP2       0x10
258 #define FLASH_STATUS_SRWP0     0x80
259 #define FLASH_STATUS_TIMEOUT   0xff
260 /* S25FL Error Flags */
261 #define S25FL_STATUS_E_ERR     0x20
262 #define S25FL_STATUS_P_ERR     0x40
263 
264 #define FLASH_PAGESIZE         256			/* In Bytes    */
265 #define FLASH_PAGESIZE_32      (FLASH_PAGESIZE / 4)	/* In uint32_t */
266 #define FLASH_MAX_BUSY_WAIT    (300 * HZ)	/* Maximum 'CHIPERASE' time */
267 
268 /*
269  * Flags to tweak operation of default read/write/erase routines
270  */
271 #define CFG_READ_TOGGLE_32BIT_ADDR     0x00000001
272 #define CFG_WRITE_TOGGLE_32BIT_ADDR    0x00000002
273 #define CFG_WRITE_EX_32BIT_ADDR_DELAY  0x00000004
274 #define CFG_ERASESEC_TOGGLE_32BIT_ADDR 0x00000008
275 #define CFG_S25FL_CHECK_ERROR_FLAGS    0x00000010
276 
277 struct stfsm_seq {
278 	uint32_t data_size;
279 	uint32_t addr1;
280 	uint32_t addr2;
281 	uint32_t addr_cfg;
282 	uint32_t seq_opc[5];
283 	uint32_t mode;
284 	uint32_t dummy;
285 	uint32_t status;
286 	uint8_t  seq[16];
287 	uint32_t seq_cfg;
288 } __packed __aligned(4);
289 
290 struct stfsm {
291 	struct device		*dev;
292 	void __iomem		*base;
293 	struct resource		*region;
294 	struct mtd_info		mtd;
295 	struct mutex		lock;
296 	struct flash_info       *info;
297 
298 	uint32_t                configuration;
299 	uint32_t                fifo_dir_delay;
300 	bool                    booted_from_spi;
301 	bool                    reset_signal;
302 	bool                    reset_por;
303 
304 	struct stfsm_seq stfsm_seq_read;
305 	struct stfsm_seq stfsm_seq_write;
306 	struct stfsm_seq stfsm_seq_en_32bit_addr;
307 };
308 
309 /* Parameters to configure a READ or WRITE FSM sequence */
310 struct seq_rw_config {
311 	uint32_t        flags;          /* flags to support config */
312 	uint8_t         cmd;            /* FLASH command */
313 	int             write;          /* Write Sequence */
314 	uint8_t         addr_pads;      /* No. of addr pads (MODE & DUMMY) */
315 	uint8_t         data_pads;      /* No. of data pads */
316 	uint8_t         mode_data;      /* MODE data */
317 	uint8_t         mode_cycles;    /* No. of MODE cycles */
318 	uint8_t         dummy_cycles;   /* No. of DUMMY cycles */
319 };
320 
321 /* SPI Flash Device Table */
322 struct flash_info {
323 	char            *name;
324 	/*
325 	 * JEDEC id zero means "no ID" (most older chips); otherwise it has
326 	 * a high byte of zero plus three data bytes: the manufacturer id,
327 	 * then a two byte device id.
328 	 */
329 	u32             jedec_id;
330 	u16             ext_id;
331 	/*
332 	 * The size listed here is what works with FLASH_CMD_SE, which isn't
333 	 * necessarily called a "sector" by the vendor.
334 	 */
335 	unsigned        sector_size;
336 	u16             n_sectors;
337 	u32             flags;
338 	/*
339 	 * Note, where FAST_READ is supported, freq_max specifies the
340 	 * FAST_READ frequency, not the READ frequency.
341 	 */
342 	u32             max_freq;
343 	int             (*config)(struct stfsm *);
344 };
345 
346 static int stfsm_n25q_config(struct stfsm *fsm);
347 static int stfsm_mx25_config(struct stfsm *fsm);
348 static int stfsm_s25fl_config(struct stfsm *fsm);
349 static int stfsm_w25q_config(struct stfsm *fsm);
350 
351 static struct flash_info flash_types[] = {
352 	/*
353 	 * ST Microelectronics/Numonyx --
354 	 * (newer production versions may have feature updates
355 	 * (eg faster operating frequency)
356 	 */
357 #define M25P_FLAG (FLASH_FLAG_READ_WRITE | FLASH_FLAG_READ_FAST)
358 	{ "m25p40",  0x202013, 0,  64 * 1024,   8, M25P_FLAG, 25, NULL },
359 	{ "m25p80",  0x202014, 0,  64 * 1024,  16, M25P_FLAG, 25, NULL },
360 	{ "m25p16",  0x202015, 0,  64 * 1024,  32, M25P_FLAG, 25, NULL },
361 	{ "m25p32",  0x202016, 0,  64 * 1024,  64, M25P_FLAG, 50, NULL },
362 	{ "m25p64",  0x202017, 0,  64 * 1024, 128, M25P_FLAG, 50, NULL },
363 	{ "m25p128", 0x202018, 0, 256 * 1024,  64, M25P_FLAG, 50, NULL },
364 
365 #define M25PX_FLAG (FLASH_FLAG_READ_WRITE      |	\
366 		    FLASH_FLAG_READ_FAST        |	\
367 		    FLASH_FLAG_READ_1_1_2       |	\
368 		    FLASH_FLAG_WRITE_1_1_2)
369 	{ "m25px32", 0x207116, 0,  64 * 1024,  64, M25PX_FLAG, 75, NULL },
370 	{ "m25px64", 0x207117, 0,  64 * 1024, 128, M25PX_FLAG, 75, NULL },
371 
372 #define MX25_FLAG (FLASH_FLAG_READ_WRITE       |	\
373 		   FLASH_FLAG_READ_FAST         |	\
374 		   FLASH_FLAG_READ_1_1_2        |	\
375 		   FLASH_FLAG_READ_1_2_2        |	\
376 		   FLASH_FLAG_READ_1_1_4        |	\
377 		   FLASH_FLAG_READ_1_4_4        |	\
378 		   FLASH_FLAG_SE_4K             |	\
379 		   FLASH_FLAG_SE_32K)
380 	{ "mx25l25635e", 0xc22019, 0, 64*1024, 512,
381 	  (MX25_FLAG | FLASH_FLAG_32BIT_ADDR | FLASH_FLAG_RESET), 70,
382 	  stfsm_mx25_config },
383 
384 #define N25Q_FLAG (FLASH_FLAG_READ_WRITE       |	\
385 		   FLASH_FLAG_READ_FAST         |	\
386 		   FLASH_FLAG_READ_1_1_2        |	\
387 		   FLASH_FLAG_READ_1_2_2        |	\
388 		   FLASH_FLAG_READ_1_1_4        |	\
389 		   FLASH_FLAG_READ_1_4_4        |	\
390 		   FLASH_FLAG_WRITE_1_1_2       |	\
391 		   FLASH_FLAG_WRITE_1_2_2       |	\
392 		   FLASH_FLAG_WRITE_1_1_4       |	\
393 		   FLASH_FLAG_WRITE_1_4_4)
394 	{ "n25q128", 0x20ba18, 0, 64 * 1024,  256, N25Q_FLAG, 108,
395 	  stfsm_n25q_config },
396 	{ "n25q256", 0x20ba19, 0, 64 * 1024,  512,
397 	  N25Q_FLAG | FLASH_FLAG_32BIT_ADDR, 108, stfsm_n25q_config },
398 
399 	/*
400 	 * Spansion S25FLxxxP
401 	 *     - 256KiB and 64KiB sector variants (identified by ext. JEDEC)
402 	 */
403 #define S25FLXXXP_FLAG (FLASH_FLAG_READ_WRITE  |	\
404 			FLASH_FLAG_READ_1_1_2   |	\
405 			FLASH_FLAG_READ_1_2_2   |	\
406 			FLASH_FLAG_READ_1_1_4   |	\
407 			FLASH_FLAG_READ_1_4_4   |	\
408 			FLASH_FLAG_WRITE_1_1_4  |	\
409 			FLASH_FLAG_READ_FAST)
410 	{ "s25fl129p0", 0x012018, 0x4d00, 256 * 1024,  64, S25FLXXXP_FLAG, 80,
411 	  stfsm_s25fl_config },
412 	{ "s25fl129p1", 0x012018, 0x4d01,  64 * 1024, 256, S25FLXXXP_FLAG, 80,
413 	  stfsm_s25fl_config },
414 
415 	/*
416 	 * Spansion S25FLxxxS
417 	 *     - 256KiB and 64KiB sector variants (identified by ext. JEDEC)
418 	 *     - RESET# signal supported by die but not bristled out on all
419 	 *       package types.  The package type is a function of board design,
420 	 *       so this information is captured in the board's flags.
421 	 *     - Supports 'DYB' sector protection. Depending on variant, sectors
422 	 *       may default to locked state on power-on.
423 	 */
424 #define S25FLXXXS_FLAG (S25FLXXXP_FLAG         |	\
425 			FLASH_FLAG_RESET        |	\
426 			FLASH_FLAG_DYB_LOCKING)
427 	{ "s25fl128s0", 0x012018, 0x0300,  256 * 1024, 64, S25FLXXXS_FLAG, 80,
428 	  stfsm_s25fl_config },
429 	{ "s25fl128s1", 0x012018, 0x0301,  64 * 1024, 256, S25FLXXXS_FLAG, 80,
430 	  stfsm_s25fl_config },
431 	{ "s25fl256s0", 0x010219, 0x4d00, 256 * 1024, 128,
432 	  S25FLXXXS_FLAG | FLASH_FLAG_32BIT_ADDR, 80, stfsm_s25fl_config },
433 	{ "s25fl256s1", 0x010219, 0x4d01,  64 * 1024, 512,
434 	  S25FLXXXS_FLAG | FLASH_FLAG_32BIT_ADDR, 80, stfsm_s25fl_config },
435 
436 	/* Winbond -- w25x "blocks" are 64K, "sectors" are 4KiB */
437 #define W25X_FLAG (FLASH_FLAG_READ_WRITE       |	\
438 		   FLASH_FLAG_READ_FAST         |	\
439 		   FLASH_FLAG_READ_1_1_2        |	\
440 		   FLASH_FLAG_WRITE_1_1_2)
441 	{ "w25x40",  0xef3013, 0,  64 * 1024,   8, W25X_FLAG, 75, NULL },
442 	{ "w25x80",  0xef3014, 0,  64 * 1024,  16, W25X_FLAG, 75, NULL },
443 	{ "w25x16",  0xef3015, 0,  64 * 1024,  32, W25X_FLAG, 75, NULL },
444 	{ "w25x32",  0xef3016, 0,  64 * 1024,  64, W25X_FLAG, 75, NULL },
445 	{ "w25x64",  0xef3017, 0,  64 * 1024, 128, W25X_FLAG, 75, NULL },
446 
447 	/* Winbond -- w25q "blocks" are 64K, "sectors" are 4KiB */
448 #define W25Q_FLAG (FLASH_FLAG_READ_WRITE       |	\
449 		   FLASH_FLAG_READ_FAST         |	\
450 		   FLASH_FLAG_READ_1_1_2        |	\
451 		   FLASH_FLAG_READ_1_2_2        |	\
452 		   FLASH_FLAG_READ_1_1_4        |	\
453 		   FLASH_FLAG_READ_1_4_4        |	\
454 		   FLASH_FLAG_WRITE_1_1_4)
455 	{ "w25q80",  0xef4014, 0,  64 * 1024,  16, W25Q_FLAG, 80,
456 	  stfsm_w25q_config },
457 	{ "w25q16",  0xef4015, 0,  64 * 1024,  32, W25Q_FLAG, 80,
458 	  stfsm_w25q_config },
459 	{ "w25q32",  0xef4016, 0,  64 * 1024,  64, W25Q_FLAG, 80,
460 	  stfsm_w25q_config },
461 	{ "w25q64",  0xef4017, 0,  64 * 1024, 128, W25Q_FLAG, 80,
462 	  stfsm_w25q_config },
463 
464 	/* Sentinel */
465 	{ NULL, 0x000000, 0, 0, 0, 0, 0, NULL },
466 };
467 
468 /*
469  * FSM message sequence configurations:
470  *
471  * All configs are presented in order of preference
472  */
473 
474 /* Default READ configurations, in order of preference */
475 static struct seq_rw_config default_read_configs[] = {
476 	{FLASH_FLAG_READ_1_4_4, FLASH_CMD_READ_1_4_4,	0, 4, 4, 0x00, 2, 4},
477 	{FLASH_FLAG_READ_1_1_4, FLASH_CMD_READ_1_1_4,	0, 1, 4, 0x00, 4, 0},
478 	{FLASH_FLAG_READ_1_2_2, FLASH_CMD_READ_1_2_2,	0, 2, 2, 0x00, 4, 0},
479 	{FLASH_FLAG_READ_1_1_2, FLASH_CMD_READ_1_1_2,	0, 1, 2, 0x00, 0, 8},
480 	{FLASH_FLAG_READ_FAST,	FLASH_CMD_READ_FAST,	0, 1, 1, 0x00, 0, 8},
481 	{FLASH_FLAG_READ_WRITE, FLASH_CMD_READ,		0, 1, 1, 0x00, 0, 0},
482 	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
483 };
484 
485 /* Default WRITE configurations */
486 static struct seq_rw_config default_write_configs[] = {
487 	{FLASH_FLAG_WRITE_1_4_4, FLASH_CMD_WRITE_1_4_4, 1, 4, 4, 0x00, 0, 0},
488 	{FLASH_FLAG_WRITE_1_1_4, FLASH_CMD_WRITE_1_1_4, 1, 1, 4, 0x00, 0, 0},
489 	{FLASH_FLAG_WRITE_1_2_2, FLASH_CMD_WRITE_1_2_2, 1, 2, 2, 0x00, 0, 0},
490 	{FLASH_FLAG_WRITE_1_1_2, FLASH_CMD_WRITE_1_1_2, 1, 1, 2, 0x00, 0, 0},
491 	{FLASH_FLAG_READ_WRITE,  FLASH_CMD_WRITE,       1, 1, 1, 0x00, 0, 0},
492 	{0x00,			 0,			0, 0, 0, 0x00, 0, 0},
493 };
494 
495 /*
496  * [N25Qxxx] Configuration
497  */
498 #define N25Q_VCR_DUMMY_CYCLES(x)	(((x) & 0xf) << 4)
499 #define N25Q_VCR_XIP_DISABLED		((uint8_t)0x1 << 3)
500 #define N25Q_VCR_WRAP_CONT		0x3
501 
502 /* N25Q 3-byte Address READ configurations
503  *	- 'FAST' variants configured for 8 dummy cycles.
504  *
505  * Note, the number of dummy cycles used for 'FAST' READ operations is
506  * configurable and would normally be tuned according to the READ command and
507  * operating frequency.  However, this applies universally to all 'FAST' READ
508  * commands, including those used by the SPIBoot controller, and remains in
509  * force until the device is power-cycled.  Since the SPIBoot controller is
510  * hard-wired to use 8 dummy cycles, we must configure the device to also use 8
511  * cycles.
512  */
513 static struct seq_rw_config n25q_read3_configs[] = {
514 	{FLASH_FLAG_READ_1_4_4, FLASH_CMD_READ_1_4_4,	0, 4, 4, 0x00, 0, 8},
515 	{FLASH_FLAG_READ_1_1_4, FLASH_CMD_READ_1_1_4,	0, 1, 4, 0x00, 0, 8},
516 	{FLASH_FLAG_READ_1_2_2, FLASH_CMD_READ_1_2_2,	0, 2, 2, 0x00, 0, 8},
517 	{FLASH_FLAG_READ_1_1_2, FLASH_CMD_READ_1_1_2,	0, 1, 2, 0x00, 0, 8},
518 	{FLASH_FLAG_READ_FAST,	FLASH_CMD_READ_FAST,	0, 1, 1, 0x00, 0, 8},
519 	{FLASH_FLAG_READ_WRITE, FLASH_CMD_READ,	        0, 1, 1, 0x00, 0, 0},
520 	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
521 };
522 
523 /* N25Q 4-byte Address READ configurations
524  *	- use special 4-byte address READ commands (reduces overheads, and
525  *        reduces risk of hitting watchdog reset issues).
526  *	- 'FAST' variants configured for 8 dummy cycles (see note above.)
527  */
528 static struct seq_rw_config n25q_read4_configs[] = {
529 	{FLASH_FLAG_READ_1_4_4, FLASH_CMD_READ4_1_4_4,	0, 4, 4, 0x00, 0, 8},
530 	{FLASH_FLAG_READ_1_1_4, FLASH_CMD_READ4_1_1_4,	0, 1, 4, 0x00, 0, 8},
531 	{FLASH_FLAG_READ_1_2_2, FLASH_CMD_READ4_1_2_2,	0, 2, 2, 0x00, 0, 8},
532 	{FLASH_FLAG_READ_1_1_2, FLASH_CMD_READ4_1_1_2,	0, 1, 2, 0x00, 0, 8},
533 	{FLASH_FLAG_READ_FAST,	FLASH_CMD_READ4_FAST,	0, 1, 1, 0x00, 0, 8},
534 	{FLASH_FLAG_READ_WRITE, FLASH_CMD_READ4,	0, 1, 1, 0x00, 0, 0},
535 	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
536 };
537 
538 /*
539  * [MX25xxx] Configuration
540  */
541 #define MX25_STATUS_QE			(0x1 << 6)
542 
543 static int stfsm_mx25_en_32bit_addr_seq(struct stfsm_seq *seq)
544 {
545 	seq->seq_opc[0] = (SEQ_OPC_PADS_1 |
546 			   SEQ_OPC_CYCLES(8) |
547 			   SEQ_OPC_OPCODE(FLASH_CMD_EN4B_ADDR) |
548 			   SEQ_OPC_CSDEASSERT);
549 
550 	seq->seq[0] = STFSM_INST_CMD1;
551 	seq->seq[1] = STFSM_INST_WAIT;
552 	seq->seq[2] = STFSM_INST_STOP;
553 
554 	seq->seq_cfg = (SEQ_CFG_PADS_1 |
555 			SEQ_CFG_ERASE |
556 			SEQ_CFG_READNOTWRITE |
557 			SEQ_CFG_CSDEASSERT |
558 			SEQ_CFG_STARTSEQ);
559 
560 	return 0;
561 }
562 
563 /*
564  * [S25FLxxx] Configuration
565  */
566 #define STFSM_S25FL_CONFIG_QE		(0x1 << 1)
567 
568 /*
569  * S25FLxxxS devices provide three ways of supporting 32-bit addressing: Bank
570  * Register, Extended Address Modes, and a 32-bit address command set.  The
571  * 32-bit address command set is used here, since it avoids any problems with
572  * entering a state that is incompatible with the SPIBoot Controller.
573  */
574 static struct seq_rw_config stfsm_s25fl_read4_configs[] = {
575 	{FLASH_FLAG_READ_1_4_4,  FLASH_CMD_READ4_1_4_4,  0, 4, 4, 0x00, 2, 4},
576 	{FLASH_FLAG_READ_1_1_4,  FLASH_CMD_READ4_1_1_4,  0, 1, 4, 0x00, 0, 8},
577 	{FLASH_FLAG_READ_1_2_2,  FLASH_CMD_READ4_1_2_2,  0, 2, 2, 0x00, 4, 0},
578 	{FLASH_FLAG_READ_1_1_2,  FLASH_CMD_READ4_1_1_2,  0, 1, 2, 0x00, 0, 8},
579 	{FLASH_FLAG_READ_FAST,   FLASH_CMD_READ4_FAST,   0, 1, 1, 0x00, 0, 8},
580 	{FLASH_FLAG_READ_WRITE,  FLASH_CMD_READ4,        0, 1, 1, 0x00, 0, 0},
581 	{0x00,                   0,                      0, 0, 0, 0x00, 0, 0},
582 };
583 
584 static struct seq_rw_config stfsm_s25fl_write4_configs[] = {
585 	{FLASH_FLAG_WRITE_1_1_4, S25FL_CMD_WRITE4_1_1_4, 1, 1, 4, 0x00, 0, 0},
586 	{FLASH_FLAG_READ_WRITE,  S25FL_CMD_WRITE4,       1, 1, 1, 0x00, 0, 0},
587 	{0x00,                   0,                      0, 0, 0, 0x00, 0, 0},
588 };
589 
590 /*
591  * [W25Qxxx] Configuration
592  */
593 #define W25Q_STATUS_QE			(0x1 << 9)
594 
595 static struct stfsm_seq stfsm_seq_read_jedec = {
596 	.data_size = TRANSFER_SIZE(8),
597 	.seq_opc[0] = (SEQ_OPC_PADS_1 |
598 		       SEQ_OPC_CYCLES(8) |
599 		       SEQ_OPC_OPCODE(FLASH_CMD_RDID)),
600 	.seq = {
601 		STFSM_INST_CMD1,
602 		STFSM_INST_DATA_READ,
603 		STFSM_INST_STOP,
604 	},
605 	.seq_cfg = (SEQ_CFG_PADS_1 |
606 		    SEQ_CFG_READNOTWRITE |
607 		    SEQ_CFG_CSDEASSERT |
608 		    SEQ_CFG_STARTSEQ),
609 };
610 
611 static struct stfsm_seq stfsm_seq_read_status_fifo = {
612 	.data_size = TRANSFER_SIZE(4),
613 	.seq_opc[0] = (SEQ_OPC_PADS_1 |
614 		       SEQ_OPC_CYCLES(8) |
615 		       SEQ_OPC_OPCODE(FLASH_CMD_RDSR)),
616 	.seq = {
617 		STFSM_INST_CMD1,
618 		STFSM_INST_DATA_READ,
619 		STFSM_INST_STOP,
620 	},
621 	.seq_cfg = (SEQ_CFG_PADS_1 |
622 		    SEQ_CFG_READNOTWRITE |
623 		    SEQ_CFG_CSDEASSERT |
624 		    SEQ_CFG_STARTSEQ),
625 };
626 
627 static struct stfsm_seq stfsm_seq_erase_sector = {
628 	/* 'addr_cfg' configured during initialisation */
629 	.seq_opc = {
630 		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
631 		 SEQ_OPC_OPCODE(FLASH_CMD_WREN) | SEQ_OPC_CSDEASSERT),
632 
633 		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
634 		 SEQ_OPC_OPCODE(FLASH_CMD_SE)),
635 	},
636 	.seq = {
637 		STFSM_INST_CMD1,
638 		STFSM_INST_CMD2,
639 		STFSM_INST_ADD1,
640 		STFSM_INST_ADD2,
641 		STFSM_INST_STOP,
642 	},
643 	.seq_cfg = (SEQ_CFG_PADS_1 |
644 		    SEQ_CFG_READNOTWRITE |
645 		    SEQ_CFG_CSDEASSERT |
646 		    SEQ_CFG_STARTSEQ),
647 };
648 
649 static struct stfsm_seq stfsm_seq_erase_chip = {
650 	.seq_opc = {
651 		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
652 		 SEQ_OPC_OPCODE(FLASH_CMD_WREN) | SEQ_OPC_CSDEASSERT),
653 
654 		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
655 		 SEQ_OPC_OPCODE(FLASH_CMD_CHIPERASE) | SEQ_OPC_CSDEASSERT),
656 	},
657 	.seq = {
658 		STFSM_INST_CMD1,
659 		STFSM_INST_CMD2,
660 		STFSM_INST_WAIT,
661 		STFSM_INST_STOP,
662 	},
663 	.seq_cfg = (SEQ_CFG_PADS_1 |
664 		    SEQ_CFG_ERASE |
665 		    SEQ_CFG_READNOTWRITE |
666 		    SEQ_CFG_CSDEASSERT |
667 		    SEQ_CFG_STARTSEQ),
668 };
669 
670 static struct stfsm_seq stfsm_seq_write_status = {
671 	.seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
672 		       SEQ_OPC_OPCODE(FLASH_CMD_WREN) | SEQ_OPC_CSDEASSERT),
673 	.seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
674 		       SEQ_OPC_OPCODE(FLASH_CMD_WRSR)),
675 	.seq = {
676 		STFSM_INST_CMD1,
677 		STFSM_INST_CMD2,
678 		STFSM_INST_STA_WR1,
679 		STFSM_INST_STOP,
680 	},
681 	.seq_cfg = (SEQ_CFG_PADS_1 |
682 		    SEQ_CFG_READNOTWRITE |
683 		    SEQ_CFG_CSDEASSERT |
684 		    SEQ_CFG_STARTSEQ),
685 };
686 
687 static struct stfsm_seq stfsm_seq_wrvcr = {
688 	.seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
689 		       SEQ_OPC_OPCODE(FLASH_CMD_WREN) | SEQ_OPC_CSDEASSERT),
690 	.seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
691 		       SEQ_OPC_OPCODE(FLASH_CMD_WRVCR)),
692 	.seq = {
693 		STFSM_INST_CMD1,
694 		STFSM_INST_CMD2,
695 		STFSM_INST_STA_WR1,
696 		STFSM_INST_STOP,
697 	},
698 	.seq_cfg = (SEQ_CFG_PADS_1 |
699 		    SEQ_CFG_READNOTWRITE |
700 		    SEQ_CFG_CSDEASSERT |
701 		    SEQ_CFG_STARTSEQ),
702 };
703 
704 static int stfsm_n25q_en_32bit_addr_seq(struct stfsm_seq *seq)
705 {
706 	seq->seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
707 			   SEQ_OPC_OPCODE(FLASH_CMD_EN4B_ADDR));
708 	seq->seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
709 			   SEQ_OPC_OPCODE(FLASH_CMD_WREN) |
710 			   SEQ_OPC_CSDEASSERT);
711 
712 	seq->seq[0] = STFSM_INST_CMD2;
713 	seq->seq[1] = STFSM_INST_CMD1;
714 	seq->seq[2] = STFSM_INST_WAIT;
715 	seq->seq[3] = STFSM_INST_STOP;
716 
717 	seq->seq_cfg = (SEQ_CFG_PADS_1 |
718 			SEQ_CFG_ERASE |
719 			SEQ_CFG_READNOTWRITE |
720 			SEQ_CFG_CSDEASSERT |
721 			SEQ_CFG_STARTSEQ);
722 
723 	return 0;
724 }
725 
726 static inline int stfsm_is_idle(struct stfsm *fsm)
727 {
728 	return readl(fsm->base + SPI_FAST_SEQ_STA) & 0x10;
729 }
730 
731 static inline uint32_t stfsm_fifo_available(struct stfsm *fsm)
732 {
733 	return (readl(fsm->base + SPI_FAST_SEQ_STA) >> 5) & 0x7f;
734 }
735 
736 static void stfsm_clear_fifo(struct stfsm *fsm)
737 {
738 	uint32_t avail;
739 
740 	for (;;) {
741 		avail = stfsm_fifo_available(fsm);
742 		if (!avail)
743 			break;
744 
745 		while (avail) {
746 			readl(fsm->base + SPI_FAST_SEQ_DATA_REG);
747 			avail--;
748 		}
749 	}
750 }
751 
752 static inline void stfsm_load_seq(struct stfsm *fsm,
753 				  const struct stfsm_seq *seq)
754 {
755 	void __iomem *dst = fsm->base + SPI_FAST_SEQ_TRANSFER_SIZE;
756 	const uint32_t *src = (const uint32_t *)seq;
757 	int words = sizeof(*seq) / sizeof(*src);
758 
759 	BUG_ON(!stfsm_is_idle(fsm));
760 
761 	while (words--) {
762 		writel(*src, dst);
763 		src++;
764 		dst += 4;
765 	}
766 }
767 
768 static void stfsm_wait_seq(struct stfsm *fsm)
769 {
770 	unsigned long deadline;
771 	int timeout = 0;
772 
773 	deadline = jiffies + msecs_to_jiffies(STFSM_MAX_WAIT_SEQ_MS);
774 
775 	while (!timeout) {
776 		if (time_after_eq(jiffies, deadline))
777 			timeout = 1;
778 
779 		if (stfsm_is_idle(fsm))
780 			return;
781 
782 		cond_resched();
783 	}
784 
785 	dev_err(fsm->dev, "timeout on sequence completion\n");
786 }
787 
788 static void stfsm_read_fifo(struct stfsm *fsm, uint32_t *buf, uint32_t size)
789 {
790 	uint32_t remaining = size >> 2;
791 	uint32_t avail;
792 	uint32_t words;
793 
794 	dev_dbg(fsm->dev, "Reading %d bytes from FIFO\n", size);
795 
796 	BUG_ON((((uint32_t)buf) & 0x3) || (size & 0x3));
797 
798 	while (remaining) {
799 		for (;;) {
800 			avail = stfsm_fifo_available(fsm);
801 			if (avail)
802 				break;
803 			udelay(1);
804 		}
805 		words = min(avail, remaining);
806 		remaining -= words;
807 
808 		readsl(fsm->base + SPI_FAST_SEQ_DATA_REG, buf, words);
809 		buf += words;
810 	}
811 }
812 
813 static int stfsm_write_fifo(struct stfsm *fsm, const uint32_t *buf,
814 			    uint32_t size)
815 {
816 	uint32_t words = size >> 2;
817 
818 	dev_dbg(fsm->dev, "writing %d bytes to FIFO\n", size);
819 
820 	BUG_ON((((uint32_t)buf) & 0x3) || (size & 0x3));
821 
822 	writesl(fsm->base + SPI_FAST_SEQ_DATA_REG, buf, words);
823 
824 	return size;
825 }
826 
827 static int stfsm_enter_32bit_addr(struct stfsm *fsm, int enter)
828 {
829 	struct stfsm_seq *seq = &fsm->stfsm_seq_en_32bit_addr;
830 	uint32_t cmd = enter ? FLASH_CMD_EN4B_ADDR : FLASH_CMD_EX4B_ADDR;
831 
832 	seq->seq_opc[0] = (SEQ_OPC_PADS_1 |
833 			   SEQ_OPC_CYCLES(8) |
834 			   SEQ_OPC_OPCODE(cmd) |
835 			   SEQ_OPC_CSDEASSERT);
836 
837 	stfsm_load_seq(fsm, seq);
838 
839 	stfsm_wait_seq(fsm);
840 
841 	return 0;
842 }
843 
844 static uint8_t stfsm_wait_busy(struct stfsm *fsm)
845 {
846 	struct stfsm_seq *seq = &stfsm_seq_read_status_fifo;
847 	unsigned long deadline;
848 	uint32_t status;
849 	int timeout = 0;
850 
851 	/* Use RDRS1 */
852 	seq->seq_opc[0] = (SEQ_OPC_PADS_1 |
853 			   SEQ_OPC_CYCLES(8) |
854 			   SEQ_OPC_OPCODE(FLASH_CMD_RDSR));
855 
856 	/* Load read_status sequence */
857 	stfsm_load_seq(fsm, seq);
858 
859 	/*
860 	 * Repeat until busy bit is deasserted, or timeout, or error (S25FLxxxS)
861 	 */
862 	deadline = jiffies + FLASH_MAX_BUSY_WAIT;
863 	while (!timeout) {
864 		if (time_after_eq(jiffies, deadline))
865 			timeout = 1;
866 
867 		stfsm_wait_seq(fsm);
868 
869 		stfsm_read_fifo(fsm, &status, 4);
870 
871 		if ((status & FLASH_STATUS_BUSY) == 0)
872 			return 0;
873 
874 		if ((fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS) &&
875 		    ((status & S25FL_STATUS_P_ERR) ||
876 		     (status & S25FL_STATUS_E_ERR)))
877 			return (uint8_t)(status & 0xff);
878 
879 		if (!timeout)
880 			/* Restart */
881 			writel(seq->seq_cfg, fsm->base + SPI_FAST_SEQ_CFG);
882 
883 		cond_resched();
884 	}
885 
886 	dev_err(fsm->dev, "timeout on wait_busy\n");
887 
888 	return FLASH_STATUS_TIMEOUT;
889 }
890 
891 static int stfsm_read_status(struct stfsm *fsm, uint8_t cmd,
892 			   uint8_t *status)
893 {
894 	struct stfsm_seq *seq = &stfsm_seq_read_status_fifo;
895 	uint32_t tmp;
896 
897 	dev_dbg(fsm->dev, "reading STA[%s]\n",
898 		(cmd == FLASH_CMD_RDSR) ? "1" : "2");
899 
900 	seq->seq_opc[0] = (SEQ_OPC_PADS_1 |
901 			   SEQ_OPC_CYCLES(8) |
902 			   SEQ_OPC_OPCODE(cmd)),
903 
904 	stfsm_load_seq(fsm, seq);
905 
906 	stfsm_read_fifo(fsm, &tmp, 4);
907 
908 	*status = (uint8_t)(tmp >> 24);
909 
910 	stfsm_wait_seq(fsm);
911 
912 	return 0;
913 }
914 
915 static int stfsm_write_status(struct stfsm *fsm, uint16_t status,
916 			       int sta_bytes)
917 {
918 	struct stfsm_seq *seq = &stfsm_seq_write_status;
919 
920 	dev_dbg(fsm->dev, "writing STA[%s] 0x%04x\n",
921 		(sta_bytes == 1) ? "1" : "1+2", status);
922 
923 	seq->status = (uint32_t)status | STA_PADS_1 | STA_CSDEASSERT;
924 	seq->seq[2] = (sta_bytes == 1) ?
925 		STFSM_INST_STA_WR1 : STFSM_INST_STA_WR1_2;
926 
927 	stfsm_load_seq(fsm, seq);
928 
929 	stfsm_wait_seq(fsm);
930 
931 	return 0;
932 };
933 
934 static int stfsm_wrvcr(struct stfsm *fsm, uint8_t data)
935 {
936 	struct stfsm_seq *seq = &stfsm_seq_wrvcr;
937 
938 	dev_dbg(fsm->dev, "writing VCR 0x%02x\n", data);
939 
940 	seq->status = (STA_DATA_BYTE1(data) | STA_PADS_1 | STA_CSDEASSERT);
941 
942 	stfsm_load_seq(fsm, seq);
943 
944 	stfsm_wait_seq(fsm);
945 
946 	return 0;
947 }
948 
949 /*
950  * SoC reset on 'boot-from-spi' systems
951  *
952  * Certain modes of operation cause the Flash device to enter a particular state
953  * for a period of time (e.g. 'Erase Sector', 'Quad Enable', and 'Enter 32-bit
954  * Addr' commands).  On boot-from-spi systems, it is important to consider what
955  * happens if a warm reset occurs during this period.  The SPIBoot controller
956  * assumes that Flash device is in its default reset state, 24-bit address mode,
957  * and ready to accept commands.  This can be achieved using some form of
958  * on-board logic/controller to force a device POR in response to a SoC-level
959  * reset or by making use of the device reset signal if available (limited
960  * number of devices only).
961  *
962  * Failure to take such precautions can cause problems following a warm reset.
963  * For some operations (e.g. ERASE), there is little that can be done.  For
964  * other modes of operation (e.g. 32-bit addressing), options are often
965  * available that can help minimise the window in which a reset could cause a
966  * problem.
967  *
968  */
969 static bool stfsm_can_handle_soc_reset(struct stfsm *fsm)
970 {
971 	/* Reset signal is available on the board and supported by the device */
972 	if (fsm->reset_signal && fsm->info->flags & FLASH_FLAG_RESET)
973 		return true;
974 
975 	/* Board-level logic forces a power-on-reset */
976 	if (fsm->reset_por)
977 		return true;
978 
979 	/* Reset is not properly handled and may result in failure to reboot */
980 	return false;
981 }
982 
983 /* Configure 'addr_cfg' according to addressing mode */
984 static void stfsm_prepare_erasesec_seq(struct stfsm *fsm,
985 				       struct stfsm_seq *seq)
986 {
987 	int addr1_cycles = fsm->info->flags & FLASH_FLAG_32BIT_ADDR ? 16 : 8;
988 
989 	seq->addr_cfg = (ADR_CFG_CYCLES_ADD1(addr1_cycles) |
990 			 ADR_CFG_PADS_1_ADD1 |
991 			 ADR_CFG_CYCLES_ADD2(16) |
992 			 ADR_CFG_PADS_1_ADD2 |
993 			 ADR_CFG_CSDEASSERT_ADD2);
994 }
995 
996 /* Search for preferred configuration based on available flags */
997 static struct seq_rw_config *
998 stfsm_search_seq_rw_configs(struct stfsm *fsm,
999 			    struct seq_rw_config cfgs[])
1000 {
1001 	struct seq_rw_config *config;
1002 	int flags = fsm->info->flags;
1003 
1004 	for (config = cfgs; config->cmd != 0; config++)
1005 		if ((config->flags & flags) == config->flags)
1006 			return config;
1007 
1008 	return NULL;
1009 }
1010 
1011 /* Prepare a READ/WRITE sequence according to configuration parameters */
1012 static void stfsm_prepare_rw_seq(struct stfsm *fsm,
1013 				 struct stfsm_seq *seq,
1014 				 struct seq_rw_config *cfg)
1015 {
1016 	int addr1_cycles, addr2_cycles;
1017 	int i = 0;
1018 
1019 	memset(seq, 0, sizeof(*seq));
1020 
1021 	/* Add READ/WRITE OPC  */
1022 	seq->seq_opc[i++] = (SEQ_OPC_PADS_1 |
1023 			     SEQ_OPC_CYCLES(8) |
1024 			     SEQ_OPC_OPCODE(cfg->cmd));
1025 
1026 	/* Add WREN OPC for a WRITE sequence */
1027 	if (cfg->write)
1028 		seq->seq_opc[i++] = (SEQ_OPC_PADS_1 |
1029 				     SEQ_OPC_CYCLES(8) |
1030 				     SEQ_OPC_OPCODE(FLASH_CMD_WREN) |
1031 				     SEQ_OPC_CSDEASSERT);
1032 
1033 	/* Address configuration (24 or 32-bit addresses) */
1034 	addr1_cycles  = (fsm->info->flags & FLASH_FLAG_32BIT_ADDR) ? 16 : 8;
1035 	addr1_cycles /= cfg->addr_pads;
1036 	addr2_cycles  = 16 / cfg->addr_pads;
1037 	seq->addr_cfg = ((addr1_cycles & 0x3f) << 0 |	/* ADD1 cycles */
1038 			 (cfg->addr_pads - 1) << 6 |	/* ADD1 pads */
1039 			 (addr2_cycles & 0x3f) << 16 |	/* ADD2 cycles */
1040 			 ((cfg->addr_pads - 1) << 22));	/* ADD2 pads */
1041 
1042 	/* Data/Sequence configuration */
1043 	seq->seq_cfg = ((cfg->data_pads - 1) << 16 |
1044 			SEQ_CFG_STARTSEQ |
1045 			SEQ_CFG_CSDEASSERT);
1046 	if (!cfg->write)
1047 		seq->seq_cfg |= SEQ_CFG_READNOTWRITE;
1048 
1049 	/* Mode configuration (no. of pads taken from addr cfg) */
1050 	seq->mode = ((cfg->mode_data & 0xff) << 0 |	/* data */
1051 		     (cfg->mode_cycles & 0x3f) << 16 |	/* cycles */
1052 		     (cfg->addr_pads - 1) << 22);	/* pads */
1053 
1054 	/* Dummy configuration (no. of pads taken from addr cfg) */
1055 	seq->dummy = ((cfg->dummy_cycles & 0x3f) << 16 |	/* cycles */
1056 		      (cfg->addr_pads - 1) << 22);		/* pads */
1057 
1058 
1059 	/* Instruction sequence */
1060 	i = 0;
1061 	if (cfg->write)
1062 		seq->seq[i++] = STFSM_INST_CMD2;
1063 
1064 	seq->seq[i++] = STFSM_INST_CMD1;
1065 
1066 	seq->seq[i++] = STFSM_INST_ADD1;
1067 	seq->seq[i++] = STFSM_INST_ADD2;
1068 
1069 	if (cfg->mode_cycles)
1070 		seq->seq[i++] = STFSM_INST_MODE;
1071 
1072 	if (cfg->dummy_cycles)
1073 		seq->seq[i++] = STFSM_INST_DUMMY;
1074 
1075 	seq->seq[i++] =
1076 		cfg->write ? STFSM_INST_DATA_WRITE : STFSM_INST_DATA_READ;
1077 	seq->seq[i++] = STFSM_INST_STOP;
1078 }
1079 
1080 static int stfsm_search_prepare_rw_seq(struct stfsm *fsm,
1081 				       struct stfsm_seq *seq,
1082 				       struct seq_rw_config *cfgs)
1083 {
1084 	struct seq_rw_config *config;
1085 
1086 	config = stfsm_search_seq_rw_configs(fsm, cfgs);
1087 	if (!config) {
1088 		dev_err(fsm->dev, "failed to find suitable config\n");
1089 		return -EINVAL;
1090 	}
1091 
1092 	stfsm_prepare_rw_seq(fsm, seq, config);
1093 
1094 	return 0;
1095 }
1096 
1097 /* Prepare a READ/WRITE/ERASE 'default' sequences */
1098 static int stfsm_prepare_rwe_seqs_default(struct stfsm *fsm)
1099 {
1100 	uint32_t flags = fsm->info->flags;
1101 	int ret;
1102 
1103 	/* Configure 'READ' sequence */
1104 	ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1105 					  default_read_configs);
1106 	if (ret) {
1107 		dev_err(fsm->dev,
1108 			"failed to prep READ sequence with flags [0x%08x]\n",
1109 			flags);
1110 		return ret;
1111 	}
1112 
1113 	/* Configure 'WRITE' sequence */
1114 	ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_write,
1115 					  default_write_configs);
1116 	if (ret) {
1117 		dev_err(fsm->dev,
1118 			"failed to prep WRITE sequence with flags [0x%08x]\n",
1119 			flags);
1120 		return ret;
1121 	}
1122 
1123 	/* Configure 'ERASE_SECTOR' sequence */
1124 	stfsm_prepare_erasesec_seq(fsm, &stfsm_seq_erase_sector);
1125 
1126 	return 0;
1127 }
1128 
1129 static int stfsm_mx25_config(struct stfsm *fsm)
1130 {
1131 	uint32_t flags = fsm->info->flags;
1132 	uint32_t data_pads;
1133 	uint8_t sta;
1134 	int ret;
1135 	bool soc_reset;
1136 
1137 	/*
1138 	 * Use default READ/WRITE sequences
1139 	 */
1140 	ret = stfsm_prepare_rwe_seqs_default(fsm);
1141 	if (ret)
1142 		return ret;
1143 
1144 	/*
1145 	 * Configure 32-bit Address Support
1146 	 */
1147 	if (flags & FLASH_FLAG_32BIT_ADDR) {
1148 		/* Configure 'enter_32bitaddr' FSM sequence */
1149 		stfsm_mx25_en_32bit_addr_seq(&fsm->stfsm_seq_en_32bit_addr);
1150 
1151 		soc_reset = stfsm_can_handle_soc_reset(fsm);
1152 		if (soc_reset || !fsm->booted_from_spi) {
1153 			/* If we can handle SoC resets, we enable 32-bit address
1154 			 * mode pervasively */
1155 			stfsm_enter_32bit_addr(fsm, 1);
1156 
1157 		} else {
1158 			/* Else, enable/disable 32-bit addressing before/after
1159 			 * each operation */
1160 			fsm->configuration = (CFG_READ_TOGGLE_32BIT_ADDR |
1161 					      CFG_WRITE_TOGGLE_32BIT_ADDR |
1162 					      CFG_ERASESEC_TOGGLE_32BIT_ADDR);
1163 			/* It seems a small delay is required after exiting
1164 			 * 32-bit mode following a write operation.  The issue
1165 			 * is under investigation.
1166 			 */
1167 			fsm->configuration |= CFG_WRITE_EX_32BIT_ADDR_DELAY;
1168 		}
1169 	}
1170 
1171 	/* For QUAD mode, set 'QE' STATUS bit */
1172 	data_pads = ((fsm->stfsm_seq_read.seq_cfg >> 16) & 0x3) + 1;
1173 	if (data_pads == 4) {
1174 		stfsm_read_status(fsm, FLASH_CMD_RDSR, &sta);
1175 		sta |= MX25_STATUS_QE;
1176 		stfsm_write_status(fsm, sta, 1);
1177 	}
1178 
1179 	return 0;
1180 }
1181 
1182 static int stfsm_n25q_config(struct stfsm *fsm)
1183 {
1184 	uint32_t flags = fsm->info->flags;
1185 	uint8_t vcr;
1186 	int ret = 0;
1187 	bool soc_reset;
1188 
1189 	/* Configure 'READ' sequence */
1190 	if (flags & FLASH_FLAG_32BIT_ADDR)
1191 		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1192 						  n25q_read4_configs);
1193 	else
1194 		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1195 						  n25q_read3_configs);
1196 	if (ret) {
1197 		dev_err(fsm->dev,
1198 			"failed to prepare READ sequence with flags [0x%08x]\n",
1199 			flags);
1200 		return ret;
1201 	}
1202 
1203 	/* Configure 'WRITE' sequence (default configs) */
1204 	ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_write,
1205 					  default_write_configs);
1206 	if (ret) {
1207 		dev_err(fsm->dev,
1208 			"preparing WRITE sequence using flags [0x%08x] failed\n",
1209 			flags);
1210 		return ret;
1211 	}
1212 
1213 	/* * Configure 'ERASE_SECTOR' sequence */
1214 	stfsm_prepare_erasesec_seq(fsm, &stfsm_seq_erase_sector);
1215 
1216 	/* Configure 32-bit address support */
1217 	if (flags & FLASH_FLAG_32BIT_ADDR) {
1218 		stfsm_n25q_en_32bit_addr_seq(&fsm->stfsm_seq_en_32bit_addr);
1219 
1220 		soc_reset = stfsm_can_handle_soc_reset(fsm);
1221 		if (soc_reset || !fsm->booted_from_spi) {
1222 			/*
1223 			 * If we can handle SoC resets, we enable 32-bit
1224 			 * address mode pervasively
1225 			 */
1226 			stfsm_enter_32bit_addr(fsm, 1);
1227 		} else {
1228 			/*
1229 			 * If not, enable/disable for WRITE and ERASE
1230 			 * operations (READ uses special commands)
1231 			 */
1232 			fsm->configuration = (CFG_WRITE_TOGGLE_32BIT_ADDR |
1233 					      CFG_ERASESEC_TOGGLE_32BIT_ADDR);
1234 		}
1235 	}
1236 
1237 	/*
1238 	 * Configure device to use 8 dummy cycles
1239 	 */
1240 	vcr = (N25Q_VCR_DUMMY_CYCLES(8) | N25Q_VCR_XIP_DISABLED |
1241 	       N25Q_VCR_WRAP_CONT);
1242 	stfsm_wrvcr(fsm, vcr);
1243 
1244 	return 0;
1245 }
1246 
1247 static void stfsm_s25fl_prepare_erasesec_seq_32(struct stfsm_seq *seq)
1248 {
1249 	seq->seq_opc[1] = (SEQ_OPC_PADS_1 |
1250 			   SEQ_OPC_CYCLES(8) |
1251 			   SEQ_OPC_OPCODE(S25FL_CMD_SE4));
1252 
1253 	seq->addr_cfg = (ADR_CFG_CYCLES_ADD1(16) |
1254 			 ADR_CFG_PADS_1_ADD1 |
1255 			 ADR_CFG_CYCLES_ADD2(16) |
1256 			 ADR_CFG_PADS_1_ADD2 |
1257 			 ADR_CFG_CSDEASSERT_ADD2);
1258 }
1259 
1260 static void stfsm_s25fl_read_dyb(struct stfsm *fsm, uint32_t offs, uint8_t *dby)
1261 {
1262 	uint32_t tmp;
1263 	struct stfsm_seq seq = {
1264 		.data_size = TRANSFER_SIZE(4),
1265 		.seq_opc[0] = (SEQ_OPC_PADS_1 |
1266 			       SEQ_OPC_CYCLES(8) |
1267 			       SEQ_OPC_OPCODE(S25FL_CMD_DYBRD)),
1268 		.addr_cfg = (ADR_CFG_CYCLES_ADD1(16) |
1269 			     ADR_CFG_PADS_1_ADD1 |
1270 			     ADR_CFG_CYCLES_ADD2(16) |
1271 			     ADR_CFG_PADS_1_ADD2),
1272 		.addr1 = (offs >> 16) & 0xffff,
1273 		.addr2 = offs & 0xffff,
1274 		.seq = {
1275 			STFSM_INST_CMD1,
1276 			STFSM_INST_ADD1,
1277 			STFSM_INST_ADD2,
1278 			STFSM_INST_DATA_READ,
1279 			STFSM_INST_STOP,
1280 		},
1281 		.seq_cfg = (SEQ_CFG_PADS_1 |
1282 			    SEQ_CFG_READNOTWRITE |
1283 			    SEQ_CFG_CSDEASSERT |
1284 			    SEQ_CFG_STARTSEQ),
1285 	};
1286 
1287 	stfsm_load_seq(fsm, &seq);
1288 
1289 	stfsm_read_fifo(fsm, &tmp, 4);
1290 
1291 	*dby = (uint8_t)(tmp >> 24);
1292 
1293 	stfsm_wait_seq(fsm);
1294 }
1295 
1296 static void stfsm_s25fl_write_dyb(struct stfsm *fsm, uint32_t offs, uint8_t dby)
1297 {
1298 	struct stfsm_seq seq = {
1299 		.seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
1300 			       SEQ_OPC_OPCODE(FLASH_CMD_WREN) |
1301 			       SEQ_OPC_CSDEASSERT),
1302 		.seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
1303 			       SEQ_OPC_OPCODE(S25FL_CMD_DYBWR)),
1304 		.addr_cfg = (ADR_CFG_CYCLES_ADD1(16) |
1305 			     ADR_CFG_PADS_1_ADD1 |
1306 			     ADR_CFG_CYCLES_ADD2(16) |
1307 			     ADR_CFG_PADS_1_ADD2),
1308 		.status = (uint32_t)dby | STA_PADS_1 | STA_CSDEASSERT,
1309 		.addr1 = (offs >> 16) & 0xffff,
1310 		.addr2 = offs & 0xffff,
1311 		.seq = {
1312 			STFSM_INST_CMD1,
1313 			STFSM_INST_CMD2,
1314 			STFSM_INST_ADD1,
1315 			STFSM_INST_ADD2,
1316 			STFSM_INST_STA_WR1,
1317 			STFSM_INST_STOP,
1318 		},
1319 		.seq_cfg = (SEQ_CFG_PADS_1 |
1320 			    SEQ_CFG_READNOTWRITE |
1321 			    SEQ_CFG_CSDEASSERT |
1322 			    SEQ_CFG_STARTSEQ),
1323 	};
1324 
1325 	stfsm_load_seq(fsm, &seq);
1326 	stfsm_wait_seq(fsm);
1327 
1328 	stfsm_wait_busy(fsm);
1329 }
1330 
1331 static int stfsm_s25fl_clear_status_reg(struct stfsm *fsm)
1332 {
1333 	struct stfsm_seq seq = {
1334 		.seq_opc[0] = (SEQ_OPC_PADS_1 |
1335 			       SEQ_OPC_CYCLES(8) |
1336 			       SEQ_OPC_OPCODE(S25FL_CMD_CLSR) |
1337 			       SEQ_OPC_CSDEASSERT),
1338 		.seq_opc[1] = (SEQ_OPC_PADS_1 |
1339 			       SEQ_OPC_CYCLES(8) |
1340 			       SEQ_OPC_OPCODE(FLASH_CMD_WRDI) |
1341 			       SEQ_OPC_CSDEASSERT),
1342 		.seq = {
1343 			STFSM_INST_CMD1,
1344 			STFSM_INST_CMD2,
1345 			STFSM_INST_WAIT,
1346 			STFSM_INST_STOP,
1347 		},
1348 		.seq_cfg = (SEQ_CFG_PADS_1 |
1349 			    SEQ_CFG_ERASE |
1350 			    SEQ_CFG_READNOTWRITE |
1351 			    SEQ_CFG_CSDEASSERT |
1352 			    SEQ_CFG_STARTSEQ),
1353 	};
1354 
1355 	stfsm_load_seq(fsm, &seq);
1356 
1357 	stfsm_wait_seq(fsm);
1358 
1359 	return 0;
1360 }
1361 
1362 static int stfsm_s25fl_config(struct stfsm *fsm)
1363 {
1364 	struct flash_info *info = fsm->info;
1365 	uint32_t flags = info->flags;
1366 	uint32_t data_pads;
1367 	uint32_t offs;
1368 	uint16_t sta_wr;
1369 	uint8_t sr1, cr1, dyb;
1370 	int ret;
1371 
1372 	if (flags & FLASH_FLAG_32BIT_ADDR) {
1373 		/*
1374 		 * Prepare Read/Write/Erase sequences according to S25FLxxx
1375 		 * 32-bit address command set
1376 		 */
1377 		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1378 						  stfsm_s25fl_read4_configs);
1379 		if (ret)
1380 			return ret;
1381 
1382 		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_write,
1383 						  stfsm_s25fl_write4_configs);
1384 		if (ret)
1385 			return ret;
1386 
1387 		stfsm_s25fl_prepare_erasesec_seq_32(&stfsm_seq_erase_sector);
1388 
1389 	} else {
1390 		/* Use default configurations for 24-bit addressing */
1391 		ret = stfsm_prepare_rwe_seqs_default(fsm);
1392 		if (ret)
1393 			return ret;
1394 	}
1395 
1396 	/*
1397 	 * For devices that support 'DYB' sector locking, check lock status and
1398 	 * unlock sectors if necessary (some variants power-on with sectors
1399 	 * locked by default)
1400 	 */
1401 	if (flags & FLASH_FLAG_DYB_LOCKING) {
1402 		offs = 0;
1403 		for (offs = 0; offs < info->sector_size * info->n_sectors;) {
1404 			stfsm_s25fl_read_dyb(fsm, offs, &dyb);
1405 			if (dyb == 0x00)
1406 				stfsm_s25fl_write_dyb(fsm, offs, 0xff);
1407 
1408 			/* Handle bottom/top 4KiB parameter sectors */
1409 			if ((offs < info->sector_size * 2) ||
1410 			    (offs >= (info->sector_size - info->n_sectors * 4)))
1411 				offs += 0x1000;
1412 			else
1413 				offs += 0x10000;
1414 		}
1415 	}
1416 
1417 	/* Check status of 'QE' bit */
1418 	data_pads = ((fsm->stfsm_seq_read.seq_cfg >> 16) & 0x3) + 1;
1419 	stfsm_read_status(fsm, FLASH_CMD_RDSR2, &cr1);
1420 	if (data_pads == 4) {
1421 		if (!(cr1 & STFSM_S25FL_CONFIG_QE)) {
1422 			/* Set 'QE' */
1423 			cr1 |= STFSM_S25FL_CONFIG_QE;
1424 
1425 			stfsm_read_status(fsm, FLASH_CMD_RDSR, &sr1);
1426 			sta_wr = ((uint16_t)cr1  << 8) | sr1;
1427 
1428 			stfsm_write_status(fsm, sta_wr, 2);
1429 
1430 			stfsm_wait_busy(fsm);
1431 		}
1432 	} else {
1433 		if ((cr1 & STFSM_S25FL_CONFIG_QE)) {
1434 			/* Clear 'QE' */
1435 			cr1 &= ~STFSM_S25FL_CONFIG_QE;
1436 
1437 			stfsm_read_status(fsm, FLASH_CMD_RDSR, &sr1);
1438 			sta_wr = ((uint16_t)cr1  << 8) | sr1;
1439 
1440 			stfsm_write_status(fsm, sta_wr, 2);
1441 
1442 			stfsm_wait_busy(fsm);
1443 		}
1444 
1445 	}
1446 
1447 	/*
1448 	 * S25FLxxx devices support Program and Error error flags.
1449 	 * Configure driver to check flags and clear if necessary.
1450 	 */
1451 	fsm->configuration |= CFG_S25FL_CHECK_ERROR_FLAGS;
1452 
1453 	return 0;
1454 }
1455 
1456 static int stfsm_w25q_config(struct stfsm *fsm)
1457 {
1458 	uint32_t data_pads;
1459 	uint16_t sta_wr;
1460 	uint8_t sta1, sta2;
1461 	int ret;
1462 
1463 	ret = stfsm_prepare_rwe_seqs_default(fsm);
1464 	if (ret)
1465 		return ret;
1466 
1467 	/* If using QUAD mode, set QE STATUS bit */
1468 	data_pads = ((fsm->stfsm_seq_read.seq_cfg >> 16) & 0x3) + 1;
1469 	if (data_pads == 4) {
1470 		stfsm_read_status(fsm, FLASH_CMD_RDSR, &sta1);
1471 		stfsm_read_status(fsm, FLASH_CMD_RDSR2, &sta2);
1472 
1473 		sta_wr = ((uint16_t)sta2 << 8) | sta1;
1474 
1475 		sta_wr |= W25Q_STATUS_QE;
1476 
1477 		stfsm_write_status(fsm, sta_wr, 2);
1478 
1479 		stfsm_wait_busy(fsm);
1480 	}
1481 
1482 	return 0;
1483 }
1484 
1485 static int stfsm_read(struct stfsm *fsm, uint8_t *buf, uint32_t size,
1486 		      uint32_t offset)
1487 {
1488 	struct stfsm_seq *seq = &fsm->stfsm_seq_read;
1489 	uint32_t data_pads;
1490 	uint32_t read_mask;
1491 	uint32_t size_ub;
1492 	uint32_t size_lb;
1493 	uint32_t size_mop;
1494 	uint32_t tmp[4];
1495 	uint32_t page_buf[FLASH_PAGESIZE_32];
1496 	uint8_t *p;
1497 
1498 	dev_dbg(fsm->dev, "reading %d bytes from 0x%08x\n", size, offset);
1499 
1500 	/* Enter 32-bit address mode, if required */
1501 	if (fsm->configuration & CFG_READ_TOGGLE_32BIT_ADDR)
1502 		stfsm_enter_32bit_addr(fsm, 1);
1503 
1504 	/* Must read in multiples of 32 cycles (or 32*pads/8 Bytes) */
1505 	data_pads = ((seq->seq_cfg >> 16) & 0x3) + 1;
1506 	read_mask = (data_pads << 2) - 1;
1507 
1508 	/* Handle non-aligned buf */
1509 	p = ((uint32_t)buf & 0x3) ? (uint8_t *)page_buf : buf;
1510 
1511 	/* Handle non-aligned size */
1512 	size_ub = (size + read_mask) & ~read_mask;
1513 	size_lb = size & ~read_mask;
1514 	size_mop = size & read_mask;
1515 
1516 	seq->data_size = TRANSFER_SIZE(size_ub);
1517 	seq->addr1 = (offset >> 16) & 0xffff;
1518 	seq->addr2 = offset & 0xffff;
1519 
1520 	stfsm_load_seq(fsm, seq);
1521 
1522 	if (size_lb)
1523 		stfsm_read_fifo(fsm, (uint32_t *)p, size_lb);
1524 
1525 	if (size_mop) {
1526 		stfsm_read_fifo(fsm, tmp, read_mask + 1);
1527 		memcpy(p + size_lb, &tmp, size_mop);
1528 	}
1529 
1530 	/* Handle non-aligned buf */
1531 	if ((uint32_t)buf & 0x3)
1532 		memcpy(buf, page_buf, size);
1533 
1534 	/* Wait for sequence to finish */
1535 	stfsm_wait_seq(fsm);
1536 
1537 	stfsm_clear_fifo(fsm);
1538 
1539 	/* Exit 32-bit address mode, if required */
1540 	if (fsm->configuration & CFG_READ_TOGGLE_32BIT_ADDR)
1541 		stfsm_enter_32bit_addr(fsm, 0);
1542 
1543 	return 0;
1544 }
1545 
1546 static int stfsm_write(struct stfsm *fsm, const uint8_t *buf,
1547 		       uint32_t size, uint32_t offset)
1548 {
1549 	struct stfsm_seq *seq = &fsm->stfsm_seq_write;
1550 	uint32_t data_pads;
1551 	uint32_t write_mask;
1552 	uint32_t size_ub;
1553 	uint32_t size_lb;
1554 	uint32_t size_mop;
1555 	uint32_t tmp[4];
1556 	uint32_t page_buf[FLASH_PAGESIZE_32];
1557 	uint8_t *t = (uint8_t *)&tmp;
1558 	const uint8_t *p;
1559 	int ret;
1560 	int i;
1561 
1562 	dev_dbg(fsm->dev, "writing %d bytes to 0x%08x\n", size, offset);
1563 
1564 	/* Enter 32-bit address mode, if required */
1565 	if (fsm->configuration & CFG_WRITE_TOGGLE_32BIT_ADDR)
1566 		stfsm_enter_32bit_addr(fsm, 1);
1567 
1568 	/* Must write in multiples of 32 cycles (or 32*pads/8 bytes) */
1569 	data_pads = ((seq->seq_cfg >> 16) & 0x3) + 1;
1570 	write_mask = (data_pads << 2) - 1;
1571 
1572 	/* Handle non-aligned buf */
1573 	if ((uint32_t)buf & 0x3) {
1574 		memcpy(page_buf, buf, size);
1575 		p = (uint8_t *)page_buf;
1576 	} else {
1577 		p = buf;
1578 	}
1579 
1580 	/* Handle non-aligned size */
1581 	size_ub = (size + write_mask) & ~write_mask;
1582 	size_lb = size & ~write_mask;
1583 	size_mop = size & write_mask;
1584 
1585 	seq->data_size = TRANSFER_SIZE(size_ub);
1586 	seq->addr1 = (offset >> 16) & 0xffff;
1587 	seq->addr2 = offset & 0xffff;
1588 
1589 	/* Need to set FIFO to write mode, before writing data to FIFO (see
1590 	 * GNBvb79594)
1591 	 */
1592 	writel(0x00040000, fsm->base + SPI_FAST_SEQ_CFG);
1593 
1594 	/*
1595 	 * Before writing data to the FIFO, apply a small delay to allow a
1596 	 * potential change of FIFO direction to complete.
1597 	 */
1598 	if (fsm->fifo_dir_delay == 0)
1599 		readl(fsm->base + SPI_FAST_SEQ_CFG);
1600 	else
1601 		udelay(fsm->fifo_dir_delay);
1602 
1603 
1604 	/* Write data to FIFO, before starting sequence (see GNBvd79593) */
1605 	if (size_lb) {
1606 		stfsm_write_fifo(fsm, (uint32_t *)p, size_lb);
1607 		p += size_lb;
1608 	}
1609 
1610 	/* Handle non-aligned size */
1611 	if (size_mop) {
1612 		memset(t, 0xff, write_mask + 1);	/* fill with 0xff's */
1613 		for (i = 0; i < size_mop; i++)
1614 			t[i] = *p++;
1615 
1616 		stfsm_write_fifo(fsm, tmp, write_mask + 1);
1617 	}
1618 
1619 	/* Start sequence */
1620 	stfsm_load_seq(fsm, seq);
1621 
1622 	/* Wait for sequence to finish */
1623 	stfsm_wait_seq(fsm);
1624 
1625 	/* Wait for completion */
1626 	ret = stfsm_wait_busy(fsm);
1627 	if (ret && fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS)
1628 		stfsm_s25fl_clear_status_reg(fsm);
1629 
1630 	/* Exit 32-bit address mode, if required */
1631 	if (fsm->configuration & CFG_WRITE_TOGGLE_32BIT_ADDR) {
1632 		stfsm_enter_32bit_addr(fsm, 0);
1633 		if (fsm->configuration & CFG_WRITE_EX_32BIT_ADDR_DELAY)
1634 			udelay(1);
1635 	}
1636 
1637 	return 0;
1638 }
1639 
1640 /*
1641  * Read an address range from the flash chip. The address range
1642  * may be any size provided it is within the physical boundaries.
1643  */
1644 static int stfsm_mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
1645 			  size_t *retlen, u_char *buf)
1646 {
1647 	struct stfsm *fsm = dev_get_drvdata(mtd->dev.parent);
1648 	uint32_t bytes;
1649 
1650 	dev_dbg(fsm->dev, "%s from 0x%08x, len %zd\n",
1651 		__func__, (u32)from, len);
1652 
1653 	mutex_lock(&fsm->lock);
1654 
1655 	while (len > 0) {
1656 		bytes = min_t(size_t, len, FLASH_PAGESIZE);
1657 
1658 		stfsm_read(fsm, buf, bytes, from);
1659 
1660 		buf += bytes;
1661 		from += bytes;
1662 		len -= bytes;
1663 
1664 		*retlen += bytes;
1665 	}
1666 
1667 	mutex_unlock(&fsm->lock);
1668 
1669 	return 0;
1670 }
1671 
1672 static int stfsm_erase_sector(struct stfsm *fsm, uint32_t offset)
1673 {
1674 	struct stfsm_seq *seq = &stfsm_seq_erase_sector;
1675 	int ret;
1676 
1677 	dev_dbg(fsm->dev, "erasing sector at 0x%08x\n", offset);
1678 
1679 	/* Enter 32-bit address mode, if required */
1680 	if (fsm->configuration & CFG_ERASESEC_TOGGLE_32BIT_ADDR)
1681 		stfsm_enter_32bit_addr(fsm, 1);
1682 
1683 	seq->addr1 = (offset >> 16) & 0xffff;
1684 	seq->addr2 = offset & 0xffff;
1685 
1686 	stfsm_load_seq(fsm, seq);
1687 
1688 	stfsm_wait_seq(fsm);
1689 
1690 	/* Wait for completion */
1691 	ret = stfsm_wait_busy(fsm);
1692 	if (ret && fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS)
1693 		stfsm_s25fl_clear_status_reg(fsm);
1694 
1695 	/* Exit 32-bit address mode, if required */
1696 	if (fsm->configuration & CFG_ERASESEC_TOGGLE_32BIT_ADDR)
1697 		stfsm_enter_32bit_addr(fsm, 0);
1698 
1699 	return ret;
1700 }
1701 
1702 static int stfsm_erase_chip(struct stfsm *fsm)
1703 {
1704 	const struct stfsm_seq *seq = &stfsm_seq_erase_chip;
1705 
1706 	dev_dbg(fsm->dev, "erasing chip\n");
1707 
1708 	stfsm_load_seq(fsm, seq);
1709 
1710 	stfsm_wait_seq(fsm);
1711 
1712 	return stfsm_wait_busy(fsm);
1713 }
1714 
1715 /*
1716  * Write an address range to the flash chip.  Data must be written in
1717  * FLASH_PAGESIZE chunks.  The address range may be any size provided
1718  * it is within the physical boundaries.
1719  */
1720 static int stfsm_mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
1721 			   size_t *retlen, const u_char *buf)
1722 {
1723 	struct stfsm *fsm = dev_get_drvdata(mtd->dev.parent);
1724 
1725 	u32 page_offs;
1726 	u32 bytes;
1727 	uint8_t *b = (uint8_t *)buf;
1728 	int ret = 0;
1729 
1730 	dev_dbg(fsm->dev, "%s to 0x%08x, len %zd\n", __func__, (u32)to, len);
1731 
1732 	/* Offset within page */
1733 	page_offs = to % FLASH_PAGESIZE;
1734 
1735 	mutex_lock(&fsm->lock);
1736 
1737 	while (len) {
1738 		/* Write up to page boundary */
1739 		bytes = min(FLASH_PAGESIZE - page_offs, len);
1740 
1741 		ret = stfsm_write(fsm, b, bytes, to);
1742 		if (ret)
1743 			goto out1;
1744 
1745 		b += bytes;
1746 		len -= bytes;
1747 		to += bytes;
1748 
1749 		/* We are now page-aligned */
1750 		page_offs = 0;
1751 
1752 		*retlen += bytes;
1753 
1754 	}
1755 
1756 out1:
1757 	mutex_unlock(&fsm->lock);
1758 
1759 	return ret;
1760 }
1761 
1762 /*
1763  * Erase an address range on the flash chip. The address range may extend
1764  * one or more erase sectors.  Return an error is there is a problem erasing.
1765  */
1766 static int stfsm_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
1767 {
1768 	struct stfsm *fsm = dev_get_drvdata(mtd->dev.parent);
1769 	u32 addr, len;
1770 	int ret;
1771 
1772 	dev_dbg(fsm->dev, "%s at 0x%llx, len %lld\n", __func__,
1773 		(long long)instr->addr, (long long)instr->len);
1774 
1775 	addr = instr->addr;
1776 	len = instr->len;
1777 
1778 	mutex_lock(&fsm->lock);
1779 
1780 	/* Whole-chip erase? */
1781 	if (len == mtd->size) {
1782 		ret = stfsm_erase_chip(fsm);
1783 		if (ret)
1784 			goto out1;
1785 	} else {
1786 		while (len) {
1787 			ret = stfsm_erase_sector(fsm, addr);
1788 			if (ret)
1789 				goto out1;
1790 
1791 			addr += mtd->erasesize;
1792 			len -= mtd->erasesize;
1793 		}
1794 	}
1795 
1796 	mutex_unlock(&fsm->lock);
1797 
1798 	instr->state = MTD_ERASE_DONE;
1799 	mtd_erase_callback(instr);
1800 
1801 	return 0;
1802 
1803 out1:
1804 	instr->state = MTD_ERASE_FAILED;
1805 	mutex_unlock(&fsm->lock);
1806 
1807 	return ret;
1808 }
1809 
1810 static void stfsm_read_jedec(struct stfsm *fsm, uint8_t *jedec)
1811 {
1812 	const struct stfsm_seq *seq = &stfsm_seq_read_jedec;
1813 	uint32_t tmp[2];
1814 
1815 	stfsm_load_seq(fsm, seq);
1816 
1817 	stfsm_read_fifo(fsm, tmp, 8);
1818 
1819 	memcpy(jedec, tmp, 5);
1820 
1821 	stfsm_wait_seq(fsm);
1822 }
1823 
1824 static struct flash_info *stfsm_jedec_probe(struct stfsm *fsm)
1825 {
1826 	struct flash_info	*info;
1827 	u16                     ext_jedec;
1828 	u32			jedec;
1829 	u8			id[5];
1830 
1831 	stfsm_read_jedec(fsm, id);
1832 
1833 	jedec     = id[0] << 16 | id[1] << 8 | id[2];
1834 	/*
1835 	 * JEDEC also defines an optional "extended device information"
1836 	 * string for after vendor-specific data, after the three bytes
1837 	 * we use here. Supporting some chips might require using it.
1838 	 */
1839 	ext_jedec = id[3] << 8  | id[4];
1840 
1841 	dev_dbg(fsm->dev, "JEDEC =  0x%08x [%02x %02x %02x %02x %02x]\n",
1842 		jedec, id[0], id[1], id[2], id[3], id[4]);
1843 
1844 	for (info = flash_types; info->name; info++) {
1845 		if (info->jedec_id == jedec) {
1846 			if (info->ext_id && info->ext_id != ext_jedec)
1847 				continue;
1848 			return info;
1849 		}
1850 	}
1851 	dev_err(fsm->dev, "Unrecognized JEDEC id %06x\n", jedec);
1852 
1853 	return NULL;
1854 }
1855 
1856 static int stfsm_set_mode(struct stfsm *fsm, uint32_t mode)
1857 {
1858 	int ret, timeout = 10;
1859 
1860 	/* Wait for controller to accept mode change */
1861 	while (--timeout) {
1862 		ret = readl(fsm->base + SPI_STA_MODE_CHANGE);
1863 		if (ret & 0x1)
1864 			break;
1865 		udelay(1);
1866 	}
1867 
1868 	if (!timeout)
1869 		return -EBUSY;
1870 
1871 	writel(mode, fsm->base + SPI_MODESELECT);
1872 
1873 	return 0;
1874 }
1875 
1876 static void stfsm_set_freq(struct stfsm *fsm, uint32_t spi_freq)
1877 {
1878 	uint32_t emi_freq;
1879 	uint32_t clk_div;
1880 
1881 	/* TODO: Make this dynamic */
1882 	emi_freq = STFSM_DEFAULT_EMI_FREQ;
1883 
1884 	/*
1885 	 * Calculate clk_div - values between 2 and 128
1886 	 * Multiple of 2, rounded up
1887 	 */
1888 	clk_div = 2 * DIV_ROUND_UP(emi_freq, 2 * spi_freq);
1889 	if (clk_div < 2)
1890 		clk_div = 2;
1891 	else if (clk_div > 128)
1892 		clk_div = 128;
1893 
1894 	/*
1895 	 * Determine a suitable delay for the IP to complete a change of
1896 	 * direction of the FIFO. The required delay is related to the clock
1897 	 * divider used. The following heuristics are based on empirical tests,
1898 	 * using a 100MHz EMI clock.
1899 	 */
1900 	if (clk_div <= 4)
1901 		fsm->fifo_dir_delay = 0;
1902 	else if (clk_div <= 10)
1903 		fsm->fifo_dir_delay = 1;
1904 	else
1905 		fsm->fifo_dir_delay = DIV_ROUND_UP(clk_div, 10);
1906 
1907 	dev_dbg(fsm->dev, "emi_clk = %uHZ, spi_freq = %uHZ, clk_div = %u\n",
1908 		emi_freq, spi_freq, clk_div);
1909 
1910 	writel(clk_div, fsm->base + SPI_CLOCKDIV);
1911 }
1912 
1913 static int stfsm_init(struct stfsm *fsm)
1914 {
1915 	int ret;
1916 
1917 	/* Perform a soft reset of the FSM controller */
1918 	writel(SEQ_CFG_SWRESET, fsm->base + SPI_FAST_SEQ_CFG);
1919 	udelay(1);
1920 	writel(0, fsm->base + SPI_FAST_SEQ_CFG);
1921 
1922 	/* Set clock to 'safe' frequency initially */
1923 	stfsm_set_freq(fsm, STFSM_FLASH_SAFE_FREQ);
1924 
1925 	/* Switch to FSM */
1926 	ret = stfsm_set_mode(fsm, SPI_MODESELECT_FSM);
1927 	if (ret)
1928 		return ret;
1929 
1930 	/* Set timing parameters */
1931 	writel(SPI_CFG_DEVICE_ST            |
1932 	       SPI_CFG_DEFAULT_MIN_CS_HIGH  |
1933 	       SPI_CFG_DEFAULT_CS_SETUPHOLD |
1934 	       SPI_CFG_DEFAULT_DATA_HOLD,
1935 	       fsm->base + SPI_CONFIGDATA);
1936 	writel(STFSM_DEFAULT_WR_TIME, fsm->base + SPI_STATUS_WR_TIME_REG);
1937 
1938 	/* Clear FIFO, just in case */
1939 	stfsm_clear_fifo(fsm);
1940 
1941 	return 0;
1942 }
1943 
1944 static void stfsm_fetch_platform_configs(struct platform_device *pdev)
1945 {
1946 	struct stfsm *fsm = platform_get_drvdata(pdev);
1947 	struct device_node *np = pdev->dev.of_node;
1948 	struct regmap *regmap;
1949 	uint32_t boot_device_reg;
1950 	uint32_t boot_device_spi;
1951 	uint32_t boot_device;     /* Value we read from *boot_device_reg */
1952 	int ret;
1953 
1954 	/* Booting from SPI NOR Flash is the default */
1955 	fsm->booted_from_spi = true;
1956 
1957 	regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
1958 	if (IS_ERR(regmap))
1959 		goto boot_device_fail;
1960 
1961 	fsm->reset_signal = of_property_read_bool(np, "st,reset-signal");
1962 
1963 	fsm->reset_por = of_property_read_bool(np, "st,reset-por");
1964 
1965 	/* Where in the syscon the boot device information lives */
1966 	ret = of_property_read_u32(np, "st,boot-device-reg", &boot_device_reg);
1967 	if (ret)
1968 		goto boot_device_fail;
1969 
1970 	/* Boot device value when booted from SPI NOR */
1971 	ret = of_property_read_u32(np, "st,boot-device-spi", &boot_device_spi);
1972 	if (ret)
1973 		goto boot_device_fail;
1974 
1975 	ret = regmap_read(regmap, boot_device_reg, &boot_device);
1976 	if (ret)
1977 		goto boot_device_fail;
1978 
1979 	if (boot_device != boot_device_spi)
1980 		fsm->booted_from_spi = false;
1981 
1982 	return;
1983 
1984 boot_device_fail:
1985 	dev_warn(&pdev->dev,
1986 		 "failed to fetch boot device, assuming boot from SPI\n");
1987 }
1988 
1989 static int stfsm_probe(struct platform_device *pdev)
1990 {
1991 	struct device_node *np = pdev->dev.of_node;
1992 	struct mtd_part_parser_data ppdata;
1993 	struct flash_info *info;
1994 	struct resource *res;
1995 	struct stfsm *fsm;
1996 	int ret;
1997 
1998 	if (!np) {
1999 		dev_err(&pdev->dev, "No DT found\n");
2000 		return -EINVAL;
2001 	}
2002 	ppdata.of_node = np;
2003 
2004 	fsm = devm_kzalloc(&pdev->dev, sizeof(*fsm), GFP_KERNEL);
2005 	if (!fsm)
2006 		return -ENOMEM;
2007 
2008 	fsm->dev = &pdev->dev;
2009 
2010 	platform_set_drvdata(pdev, fsm);
2011 
2012 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2013 	if (!res) {
2014 		dev_err(&pdev->dev, "Resource not found\n");
2015 		return -ENODEV;
2016 	}
2017 
2018 	fsm->base = devm_ioremap_resource(&pdev->dev, res);
2019 	if (IS_ERR(fsm->base)) {
2020 		dev_err(&pdev->dev,
2021 			"Failed to reserve memory region %pR\n", res);
2022 		return PTR_ERR(fsm->base);
2023 	}
2024 
2025 	mutex_init(&fsm->lock);
2026 
2027 	ret = stfsm_init(fsm);
2028 	if (ret) {
2029 		dev_err(&pdev->dev, "Failed to initialise FSM Controller\n");
2030 		return ret;
2031 	}
2032 
2033 	stfsm_fetch_platform_configs(pdev);
2034 
2035 	/* Detect SPI FLASH device */
2036 	info = stfsm_jedec_probe(fsm);
2037 	if (!info)
2038 		return -ENODEV;
2039 	fsm->info = info;
2040 
2041 	/* Use device size to determine address width */
2042 	if (info->sector_size * info->n_sectors > 0x1000000)
2043 		info->flags |= FLASH_FLAG_32BIT_ADDR;
2044 
2045 	/*
2046 	 * Configure READ/WRITE/ERASE sequences according to platform and
2047 	 * device flags.
2048 	 */
2049 	if (info->config) {
2050 		ret = info->config(fsm);
2051 		if (ret)
2052 			return ret;
2053 	} else {
2054 		ret = stfsm_prepare_rwe_seqs_default(fsm);
2055 		if (ret)
2056 			return ret;
2057 	}
2058 
2059 	fsm->mtd.name		= info->name;
2060 	fsm->mtd.dev.parent	= &pdev->dev;
2061 	fsm->mtd.type		= MTD_NORFLASH;
2062 	fsm->mtd.writesize	= 4;
2063 	fsm->mtd.writebufsize	= fsm->mtd.writesize;
2064 	fsm->mtd.flags		= MTD_CAP_NORFLASH;
2065 	fsm->mtd.size		= info->sector_size * info->n_sectors;
2066 	fsm->mtd.erasesize	= info->sector_size;
2067 
2068 	fsm->mtd._read  = stfsm_mtd_read;
2069 	fsm->mtd._write = stfsm_mtd_write;
2070 	fsm->mtd._erase = stfsm_mtd_erase;
2071 
2072 	dev_info(&pdev->dev,
2073 		"Found serial flash device: %s\n"
2074 		" size = %llx (%lldMiB) erasesize = 0x%08x (%uKiB)\n",
2075 		info->name,
2076 		(long long)fsm->mtd.size, (long long)(fsm->mtd.size >> 20),
2077 		fsm->mtd.erasesize, (fsm->mtd.erasesize >> 10));
2078 
2079 	return mtd_device_parse_register(&fsm->mtd, NULL, &ppdata, NULL, 0);
2080 }
2081 
2082 static int stfsm_remove(struct platform_device *pdev)
2083 {
2084 	struct stfsm *fsm = platform_get_drvdata(pdev);
2085 
2086 	return mtd_device_unregister(&fsm->mtd);
2087 }
2088 
2089 static struct of_device_id stfsm_match[] = {
2090 	{ .compatible = "st,spi-fsm", },
2091 	{},
2092 };
2093 MODULE_DEVICE_TABLE(of, stfsm_match);
2094 
2095 static struct platform_driver stfsm_driver = {
2096 	.probe		= stfsm_probe,
2097 	.remove		= stfsm_remove,
2098 	.driver		= {
2099 		.name	= "st-spi-fsm",
2100 		.owner	= THIS_MODULE,
2101 		.of_match_table = stfsm_match,
2102 	},
2103 };
2104 module_platform_driver(stfsm_driver);
2105 
2106 MODULE_AUTHOR("Angus Clark <angus.clark@st.com>");
2107 MODULE_DESCRIPTION("ST SPI FSM driver");
2108 MODULE_LICENSE("GPL");
2109