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/mtd/spi-nor.h>
23#include <linux/sched.h>
24#include <linux/delay.h>
25#include <linux/io.h>
26#include <linux/of.h>
27#include <linux/clk.h>
28
29#include "serial_flash_cmds.h"
30
31/*
32 * FSM SPI Controller Registers
33 */
34#define SPI_CLOCKDIV			0x0010
35#define SPI_MODESELECT			0x0018
36#define SPI_CONFIGDATA			0x0020
37#define SPI_STA_MODE_CHANGE		0x0028
38#define SPI_FAST_SEQ_TRANSFER_SIZE	0x0100
39#define SPI_FAST_SEQ_ADD1		0x0104
40#define SPI_FAST_SEQ_ADD2		0x0108
41#define SPI_FAST_SEQ_ADD_CFG		0x010c
42#define SPI_FAST_SEQ_OPC1		0x0110
43#define SPI_FAST_SEQ_OPC2		0x0114
44#define SPI_FAST_SEQ_OPC3		0x0118
45#define SPI_FAST_SEQ_OPC4		0x011c
46#define SPI_FAST_SEQ_OPC5		0x0120
47#define SPI_MODE_BITS			0x0124
48#define SPI_DUMMY_BITS			0x0128
49#define SPI_FAST_SEQ_FLASH_STA_DATA	0x012c
50#define SPI_FAST_SEQ_1			0x0130
51#define SPI_FAST_SEQ_2			0x0134
52#define SPI_FAST_SEQ_3			0x0138
53#define SPI_FAST_SEQ_4			0x013c
54#define SPI_FAST_SEQ_CFG		0x0140
55#define SPI_FAST_SEQ_STA		0x0144
56#define SPI_QUAD_BOOT_SEQ_INIT_1	0x0148
57#define SPI_QUAD_BOOT_SEQ_INIT_2	0x014c
58#define SPI_QUAD_BOOT_READ_SEQ_1	0x0150
59#define SPI_QUAD_BOOT_READ_SEQ_2	0x0154
60#define SPI_PROGRAM_ERASE_TIME		0x0158
61#define SPI_MULT_PAGE_REPEAT_SEQ_1	0x015c
62#define SPI_MULT_PAGE_REPEAT_SEQ_2	0x0160
63#define SPI_STATUS_WR_TIME_REG		0x0164
64#define SPI_FAST_SEQ_DATA_REG		0x0300
65
66/*
67 * Register: SPI_MODESELECT
68 */
69#define SPI_MODESELECT_CONTIG		0x01
70#define SPI_MODESELECT_FASTREAD		0x02
71#define SPI_MODESELECT_DUALIO		0x04
72#define SPI_MODESELECT_FSM		0x08
73#define SPI_MODESELECT_QUADBOOT		0x10
74
75/*
76 * Register: SPI_CONFIGDATA
77 */
78#define SPI_CFG_DEVICE_ST		0x1
79#define SPI_CFG_DEVICE_ATMEL		0x4
80#define SPI_CFG_MIN_CS_HIGH(x)		(((x) & 0xfff) << 4)
81#define SPI_CFG_CS_SETUPHOLD(x)		(((x) & 0xff) << 16)
82#define SPI_CFG_DATA_HOLD(x)		(((x) & 0xff) << 24)
83
84#define SPI_CFG_DEFAULT_MIN_CS_HIGH    SPI_CFG_MIN_CS_HIGH(0x0AA)
85#define SPI_CFG_DEFAULT_CS_SETUPHOLD   SPI_CFG_CS_SETUPHOLD(0xA0)
86#define SPI_CFG_DEFAULT_DATA_HOLD      SPI_CFG_DATA_HOLD(0x00)
87
88/*
89 * Register: SPI_FAST_SEQ_TRANSFER_SIZE
90 */
91#define TRANSFER_SIZE(x)		((x) * 8)
92
93/*
94 * Register: SPI_FAST_SEQ_ADD_CFG
95 */
96#define ADR_CFG_CYCLES_ADD1(x)		((x) << 0)
97#define ADR_CFG_PADS_1_ADD1		(0x0 << 6)
98#define ADR_CFG_PADS_2_ADD1		(0x1 << 6)
99#define ADR_CFG_PADS_4_ADD1		(0x3 << 6)
100#define ADR_CFG_CSDEASSERT_ADD1		(1   << 8)
101#define ADR_CFG_CYCLES_ADD2(x)		((x) << (0+16))
102#define ADR_CFG_PADS_1_ADD2		(0x0 << (6+16))
103#define ADR_CFG_PADS_2_ADD2		(0x1 << (6+16))
104#define ADR_CFG_PADS_4_ADD2		(0x3 << (6+16))
105#define ADR_CFG_CSDEASSERT_ADD2		(1   << (8+16))
106
107/*
108 * Register: SPI_FAST_SEQ_n
109 */
110#define SEQ_OPC_OPCODE(x)		((x) << 0)
111#define SEQ_OPC_CYCLES(x)		((x) << 8)
112#define SEQ_OPC_PADS_1			(0x0 << 14)
113#define SEQ_OPC_PADS_2			(0x1 << 14)
114#define SEQ_OPC_PADS_4			(0x3 << 14)
115#define SEQ_OPC_CSDEASSERT		(1   << 16)
116
117/*
118 * Register: SPI_FAST_SEQ_CFG
119 */
120#define SEQ_CFG_STARTSEQ		(1 << 0)
121#define SEQ_CFG_SWRESET			(1 << 5)
122#define SEQ_CFG_CSDEASSERT		(1 << 6)
123#define SEQ_CFG_READNOTWRITE		(1 << 7)
124#define SEQ_CFG_ERASE			(1 << 8)
125#define SEQ_CFG_PADS_1			(0x0 << 16)
126#define SEQ_CFG_PADS_2			(0x1 << 16)
127#define SEQ_CFG_PADS_4			(0x3 << 16)
128
129/*
130 * Register: SPI_MODE_BITS
131 */
132#define MODE_DATA(x)			(x & 0xff)
133#define MODE_CYCLES(x)			((x & 0x3f) << 16)
134#define MODE_PADS_1			(0x0 << 22)
135#define MODE_PADS_2			(0x1 << 22)
136#define MODE_PADS_4			(0x3 << 22)
137#define DUMMY_CSDEASSERT		(1   << 24)
138
139/*
140 * Register: SPI_DUMMY_BITS
141 */
142#define DUMMY_CYCLES(x)			((x & 0x3f) << 16)
143#define DUMMY_PADS_1			(0x0 << 22)
144#define DUMMY_PADS_2			(0x1 << 22)
145#define DUMMY_PADS_4			(0x3 << 22)
146#define DUMMY_CSDEASSERT		(1   << 24)
147
148/*
149 * Register: SPI_FAST_SEQ_FLASH_STA_DATA
150 */
151#define STA_DATA_BYTE1(x)		((x & 0xff) << 0)
152#define STA_DATA_BYTE2(x)		((x & 0xff) << 8)
153#define STA_PADS_1			(0x0 << 16)
154#define STA_PADS_2			(0x1 << 16)
155#define STA_PADS_4			(0x3 << 16)
156#define STA_CSDEASSERT			(0x1 << 20)
157#define STA_RDNOTWR			(0x1 << 21)
158
159/*
160 * FSM SPI Instruction Opcodes
161 */
162#define STFSM_OPC_CMD			0x1
163#define STFSM_OPC_ADD			0x2
164#define STFSM_OPC_STA			0x3
165#define STFSM_OPC_MODE			0x4
166#define STFSM_OPC_DUMMY		0x5
167#define STFSM_OPC_DATA			0x6
168#define STFSM_OPC_WAIT			0x7
169#define STFSM_OPC_JUMP			0x8
170#define STFSM_OPC_GOTO			0x9
171#define STFSM_OPC_STOP			0xF
172
173/*
174 * FSM SPI Instructions (== opcode + operand).
175 */
176#define STFSM_INSTR(cmd, op)		((cmd) | ((op) << 4))
177
178#define STFSM_INST_CMD1			STFSM_INSTR(STFSM_OPC_CMD,	1)
179#define STFSM_INST_CMD2			STFSM_INSTR(STFSM_OPC_CMD,	2)
180#define STFSM_INST_CMD3			STFSM_INSTR(STFSM_OPC_CMD,	3)
181#define STFSM_INST_CMD4			STFSM_INSTR(STFSM_OPC_CMD,	4)
182#define STFSM_INST_CMD5			STFSM_INSTR(STFSM_OPC_CMD,	5)
183#define STFSM_INST_ADD1			STFSM_INSTR(STFSM_OPC_ADD,	1)
184#define STFSM_INST_ADD2			STFSM_INSTR(STFSM_OPC_ADD,	2)
185
186#define STFSM_INST_DATA_WRITE		STFSM_INSTR(STFSM_OPC_DATA,	1)
187#define STFSM_INST_DATA_READ		STFSM_INSTR(STFSM_OPC_DATA,	2)
188
189#define STFSM_INST_STA_RD1		STFSM_INSTR(STFSM_OPC_STA,	0x1)
190#define STFSM_INST_STA_WR1		STFSM_INSTR(STFSM_OPC_STA,	0x1)
191#define STFSM_INST_STA_RD2		STFSM_INSTR(STFSM_OPC_STA,	0x2)
192#define STFSM_INST_STA_WR1_2		STFSM_INSTR(STFSM_OPC_STA,	0x3)
193
194#define STFSM_INST_MODE			STFSM_INSTR(STFSM_OPC_MODE,	0)
195#define STFSM_INST_DUMMY		STFSM_INSTR(STFSM_OPC_DUMMY,	0)
196#define STFSM_INST_WAIT			STFSM_INSTR(STFSM_OPC_WAIT,	0)
197#define STFSM_INST_STOP			STFSM_INSTR(STFSM_OPC_STOP,	0)
198
199#define STFSM_DEFAULT_EMI_FREQ 100000000UL                        /* 100 MHz */
200#define STFSM_DEFAULT_WR_TIME  (STFSM_DEFAULT_EMI_FREQ * (15/1000)) /* 15ms */
201
202#define STFSM_FLASH_SAFE_FREQ  10000000UL                         /* 10 MHz */
203
204#define STFSM_MAX_WAIT_SEQ_MS  1000     /* FSM execution time */
205
206/* S25FLxxxS commands */
207#define S25FL_CMD_WRITE4_1_1_4 0x34
208#define S25FL_CMD_SE4          0xdc
209#define S25FL_CMD_CLSR         0x30
210#define S25FL_CMD_DYBWR                0xe1
211#define S25FL_CMD_DYBRD                0xe0
212#define S25FL_CMD_WRITE4       0x12    /* Note, opcode clashes with
213					* 'SPINOR_OP_WRITE_1_4_4'
214					* as found on N25Qxxx devices! */
215
216/* Status register */
217#define FLASH_STATUS_BUSY      0x01
218#define FLASH_STATUS_WEL       0x02
219#define FLASH_STATUS_BP0       0x04
220#define FLASH_STATUS_BP1       0x08
221#define FLASH_STATUS_BP2       0x10
222#define FLASH_STATUS_SRWP0     0x80
223#define FLASH_STATUS_TIMEOUT   0xff
224/* S25FL Error Flags */
225#define S25FL_STATUS_E_ERR     0x20
226#define S25FL_STATUS_P_ERR     0x40
227
228#define N25Q_CMD_WRVCR         0x81
229#define N25Q_CMD_RDVCR         0x85
230#define N25Q_CMD_RDVECR        0x65
231#define N25Q_CMD_RDNVCR        0xb5
232#define N25Q_CMD_WRNVCR        0xb1
233
234#define FLASH_PAGESIZE         256			/* In Bytes    */
235#define FLASH_PAGESIZE_32      (FLASH_PAGESIZE / 4)	/* In uint32_t */
236#define FLASH_MAX_BUSY_WAIT    (300 * HZ)	/* Maximum 'CHIPERASE' time */
237
238/*
239 * Flags to tweak operation of default read/write/erase routines
240 */
241#define CFG_READ_TOGGLE_32BIT_ADDR     0x00000001
242#define CFG_WRITE_TOGGLE_32BIT_ADDR    0x00000002
243#define CFG_ERASESEC_TOGGLE_32BIT_ADDR 0x00000008
244#define CFG_S25FL_CHECK_ERROR_FLAGS    0x00000010
245
246struct stfsm_seq {
247	uint32_t data_size;
248	uint32_t addr1;
249	uint32_t addr2;
250	uint32_t addr_cfg;
251	uint32_t seq_opc[5];
252	uint32_t mode;
253	uint32_t dummy;
254	uint32_t status;
255	uint8_t  seq[16];
256	uint32_t seq_cfg;
257} __packed __aligned(4);
258
259struct stfsm {
260	struct device		*dev;
261	void __iomem		*base;
262	struct resource		*region;
263	struct mtd_info		mtd;
264	struct mutex		lock;
265	struct flash_info       *info;
266	struct clk              *clk;
267
268	uint32_t                configuration;
269	uint32_t                fifo_dir_delay;
270	bool                    booted_from_spi;
271	bool                    reset_signal;
272	bool                    reset_por;
273
274	struct stfsm_seq stfsm_seq_read;
275	struct stfsm_seq stfsm_seq_write;
276	struct stfsm_seq stfsm_seq_en_32bit_addr;
277};
278
279/* Parameters to configure a READ or WRITE FSM sequence */
280struct seq_rw_config {
281	uint32_t        flags;          /* flags to support config */
282	uint8_t         cmd;            /* FLASH command */
283	int             write;          /* Write Sequence */
284	uint8_t         addr_pads;      /* No. of addr pads (MODE & DUMMY) */
285	uint8_t         data_pads;      /* No. of data pads */
286	uint8_t         mode_data;      /* MODE data */
287	uint8_t         mode_cycles;    /* No. of MODE cycles */
288	uint8_t         dummy_cycles;   /* No. of DUMMY cycles */
289};
290
291/* SPI Flash Device Table */
292struct flash_info {
293	char            *name;
294	/*
295	 * JEDEC id zero means "no ID" (most older chips); otherwise it has
296	 * a high byte of zero plus three data bytes: the manufacturer id,
297	 * then a two byte device id.
298	 */
299	u32             jedec_id;
300	u16             ext_id;
301	/*
302	 * The size listed here is what works with SPINOR_OP_SE, which isn't
303	 * necessarily called a "sector" by the vendor.
304	 */
305	unsigned        sector_size;
306	u16             n_sectors;
307	u32             flags;
308	/*
309	 * Note, where FAST_READ is supported, freq_max specifies the
310	 * FAST_READ frequency, not the READ frequency.
311	 */
312	u32             max_freq;
313	int             (*config)(struct stfsm *);
314};
315
316static int stfsm_n25q_config(struct stfsm *fsm);
317static int stfsm_mx25_config(struct stfsm *fsm);
318static int stfsm_s25fl_config(struct stfsm *fsm);
319static int stfsm_w25q_config(struct stfsm *fsm);
320
321static struct flash_info flash_types[] = {
322	/*
323	 * ST Microelectronics/Numonyx --
324	 * (newer production versions may have feature updates
325	 * (eg faster operating frequency)
326	 */
327#define M25P_FLAG (FLASH_FLAG_READ_WRITE | FLASH_FLAG_READ_FAST)
328	{ "m25p40",  0x202013, 0,  64 * 1024,   8, M25P_FLAG, 25, NULL },
329	{ "m25p80",  0x202014, 0,  64 * 1024,  16, M25P_FLAG, 25, NULL },
330	{ "m25p16",  0x202015, 0,  64 * 1024,  32, M25P_FLAG, 25, NULL },
331	{ "m25p32",  0x202016, 0,  64 * 1024,  64, M25P_FLAG, 50, NULL },
332	{ "m25p64",  0x202017, 0,  64 * 1024, 128, M25P_FLAG, 50, NULL },
333	{ "m25p128", 0x202018, 0, 256 * 1024,  64, M25P_FLAG, 50, NULL },
334
335#define M25PX_FLAG (FLASH_FLAG_READ_WRITE      |	\
336		    FLASH_FLAG_READ_FAST        |	\
337		    FLASH_FLAG_READ_1_1_2       |	\
338		    FLASH_FLAG_WRITE_1_1_2)
339	{ "m25px32", 0x207116, 0,  64 * 1024,  64, M25PX_FLAG, 75, NULL },
340	{ "m25px64", 0x207117, 0,  64 * 1024, 128, M25PX_FLAG, 75, NULL },
341
342	/* Macronix MX25xxx
343	 *     - Support for 'FLASH_FLAG_WRITE_1_4_4' is omitted for devices
344	 *       where operating frequency must be reduced.
345	 */
346#define MX25_FLAG (FLASH_FLAG_READ_WRITE       |	\
347		   FLASH_FLAG_READ_FAST         |	\
348		   FLASH_FLAG_READ_1_1_2        |	\
349		   FLASH_FLAG_READ_1_2_2        |	\
350		   FLASH_FLAG_READ_1_1_4        |	\
351		   FLASH_FLAG_SE_4K             |	\
352		   FLASH_FLAG_SE_32K)
353	{ "mx25l3255e",  0xc29e16, 0, 64 * 1024, 64,
354	  (MX25_FLAG | FLASH_FLAG_WRITE_1_4_4), 86,
355	  stfsm_mx25_config},
356	{ "mx25l25635e", 0xc22019, 0, 64*1024, 512,
357	  (MX25_FLAG | FLASH_FLAG_32BIT_ADDR | FLASH_FLAG_RESET), 70,
358	  stfsm_mx25_config },
359	{ "mx25l25655e", 0xc22619, 0, 64*1024, 512,
360	  (MX25_FLAG | FLASH_FLAG_32BIT_ADDR | FLASH_FLAG_RESET), 70,
361	  stfsm_mx25_config},
362
363#define N25Q_FLAG (FLASH_FLAG_READ_WRITE       |	\
364		   FLASH_FLAG_READ_FAST         |	\
365		   FLASH_FLAG_READ_1_1_2        |	\
366		   FLASH_FLAG_READ_1_2_2        |	\
367		   FLASH_FLAG_READ_1_1_4        |	\
368		   FLASH_FLAG_READ_1_4_4        |	\
369		   FLASH_FLAG_WRITE_1_1_2       |	\
370		   FLASH_FLAG_WRITE_1_2_2       |	\
371		   FLASH_FLAG_WRITE_1_1_4       |	\
372		   FLASH_FLAG_WRITE_1_4_4)
373	{ "n25q128", 0x20ba18, 0, 64 * 1024,  256, N25Q_FLAG, 108,
374	  stfsm_n25q_config },
375	{ "n25q256", 0x20ba19, 0, 64 * 1024,  512,
376	  N25Q_FLAG | FLASH_FLAG_32BIT_ADDR, 108, stfsm_n25q_config },
377
378	/*
379	 * Spansion S25FLxxxP
380	 *     - 256KiB and 64KiB sector variants (identified by ext. JEDEC)
381	 */
382#define S25FLXXXP_FLAG (FLASH_FLAG_READ_WRITE  |	\
383			FLASH_FLAG_READ_1_1_2   |	\
384			FLASH_FLAG_READ_1_2_2   |	\
385			FLASH_FLAG_READ_1_1_4   |	\
386			FLASH_FLAG_READ_1_4_4   |	\
387			FLASH_FLAG_WRITE_1_1_4  |	\
388			FLASH_FLAG_READ_FAST)
389	{ "s25fl032p",  0x010215, 0x4d00,  64 * 1024,  64, S25FLXXXP_FLAG, 80,
390	  stfsm_s25fl_config},
391	{ "s25fl129p0", 0x012018, 0x4d00, 256 * 1024,  64, S25FLXXXP_FLAG, 80,
392	  stfsm_s25fl_config },
393	{ "s25fl129p1", 0x012018, 0x4d01,  64 * 1024, 256, S25FLXXXP_FLAG, 80,
394	  stfsm_s25fl_config },
395
396	/*
397	 * Spansion S25FLxxxS
398	 *     - 256KiB and 64KiB sector variants (identified by ext. JEDEC)
399	 *     - RESET# signal supported by die but not bristled out on all
400	 *       package types.  The package type is a function of board design,
401	 *       so this information is captured in the board's flags.
402	 *     - Supports 'DYB' sector protection. Depending on variant, sectors
403	 *       may default to locked state on power-on.
404	 */
405#define S25FLXXXS_FLAG (S25FLXXXP_FLAG         |	\
406			FLASH_FLAG_RESET        |	\
407			FLASH_FLAG_DYB_LOCKING)
408	{ "s25fl128s0", 0x012018, 0x0300,  256 * 1024, 64, S25FLXXXS_FLAG, 80,
409	  stfsm_s25fl_config },
410	{ "s25fl128s1", 0x012018, 0x0301,  64 * 1024, 256, S25FLXXXS_FLAG, 80,
411	  stfsm_s25fl_config },
412	{ "s25fl256s0", 0x010219, 0x4d00, 256 * 1024, 128,
413	  S25FLXXXS_FLAG | FLASH_FLAG_32BIT_ADDR, 80, stfsm_s25fl_config },
414	{ "s25fl256s1", 0x010219, 0x4d01,  64 * 1024, 512,
415	  S25FLXXXS_FLAG | FLASH_FLAG_32BIT_ADDR, 80, stfsm_s25fl_config },
416
417	/* Winbond -- w25x "blocks" are 64K, "sectors" are 4KiB */
418#define W25X_FLAG (FLASH_FLAG_READ_WRITE       |	\
419		   FLASH_FLAG_READ_FAST         |	\
420		   FLASH_FLAG_READ_1_1_2        |	\
421		   FLASH_FLAG_WRITE_1_1_2)
422	{ "w25x40",  0xef3013, 0,  64 * 1024,   8, W25X_FLAG, 75, NULL },
423	{ "w25x80",  0xef3014, 0,  64 * 1024,  16, W25X_FLAG, 75, NULL },
424	{ "w25x16",  0xef3015, 0,  64 * 1024,  32, W25X_FLAG, 75, NULL },
425	{ "w25x32",  0xef3016, 0,  64 * 1024,  64, W25X_FLAG, 75, NULL },
426	{ "w25x64",  0xef3017, 0,  64 * 1024, 128, W25X_FLAG, 75, NULL },
427
428	/* Winbond -- w25q "blocks" are 64K, "sectors" are 4KiB */
429#define W25Q_FLAG (FLASH_FLAG_READ_WRITE       |	\
430		   FLASH_FLAG_READ_FAST         |	\
431		   FLASH_FLAG_READ_1_1_2        |	\
432		   FLASH_FLAG_READ_1_2_2        |	\
433		   FLASH_FLAG_READ_1_1_4        |	\
434		   FLASH_FLAG_READ_1_4_4        |	\
435		   FLASH_FLAG_WRITE_1_1_4)
436	{ "w25q80",  0xef4014, 0,  64 * 1024,  16, W25Q_FLAG, 80,
437	  stfsm_w25q_config },
438	{ "w25q16",  0xef4015, 0,  64 * 1024,  32, W25Q_FLAG, 80,
439	  stfsm_w25q_config },
440	{ "w25q32",  0xef4016, 0,  64 * 1024,  64, W25Q_FLAG, 80,
441	  stfsm_w25q_config },
442	{ "w25q64",  0xef4017, 0,  64 * 1024, 128, W25Q_FLAG, 80,
443	  stfsm_w25q_config },
444
445	/* Sentinel */
446	{ NULL, 0x000000, 0, 0, 0, 0, 0, NULL },
447};
448
449/*
450 * FSM message sequence configurations:
451 *
452 * All configs are presented in order of preference
453 */
454
455/* Default READ configurations, in order of preference */
456static struct seq_rw_config default_read_configs[] = {
457	{FLASH_FLAG_READ_1_4_4, SPINOR_OP_READ_1_4_4,	0, 4, 4, 0x00, 2, 4},
458	{FLASH_FLAG_READ_1_1_4, SPINOR_OP_READ_1_1_4,	0, 1, 4, 0x00, 4, 0},
459	{FLASH_FLAG_READ_1_2_2, SPINOR_OP_READ_1_2_2,	0, 2, 2, 0x00, 4, 0},
460	{FLASH_FLAG_READ_1_1_2, SPINOR_OP_READ_1_1_2,	0, 1, 2, 0x00, 0, 8},
461	{FLASH_FLAG_READ_FAST,	SPINOR_OP_READ_FAST,	0, 1, 1, 0x00, 0, 8},
462	{FLASH_FLAG_READ_WRITE, SPINOR_OP_READ,		0, 1, 1, 0x00, 0, 0},
463	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
464};
465
466/* Default WRITE configurations */
467static struct seq_rw_config default_write_configs[] = {
468	{FLASH_FLAG_WRITE_1_4_4, SPINOR_OP_WRITE_1_4_4, 1, 4, 4, 0x00, 0, 0},
469	{FLASH_FLAG_WRITE_1_1_4, SPINOR_OP_WRITE_1_1_4, 1, 1, 4, 0x00, 0, 0},
470	{FLASH_FLAG_WRITE_1_2_2, SPINOR_OP_WRITE_1_2_2, 1, 2, 2, 0x00, 0, 0},
471	{FLASH_FLAG_WRITE_1_1_2, SPINOR_OP_WRITE_1_1_2, 1, 1, 2, 0x00, 0, 0},
472	{FLASH_FLAG_READ_WRITE,  SPINOR_OP_WRITE,       1, 1, 1, 0x00, 0, 0},
473	{0x00,			 0,			0, 0, 0, 0x00, 0, 0},
474};
475
476/*
477 * [N25Qxxx] Configuration
478 */
479#define N25Q_VCR_DUMMY_CYCLES(x)	(((x) & 0xf) << 4)
480#define N25Q_VCR_XIP_DISABLED		((uint8_t)0x1 << 3)
481#define N25Q_VCR_WRAP_CONT		0x3
482
483/* N25Q 3-byte Address READ configurations
484 *	- 'FAST' variants configured for 8 dummy cycles.
485 *
486 * Note, the number of dummy cycles used for 'FAST' READ operations is
487 * configurable and would normally be tuned according to the READ command and
488 * operating frequency.  However, this applies universally to all 'FAST' READ
489 * commands, including those used by the SPIBoot controller, and remains in
490 * force until the device is power-cycled.  Since the SPIBoot controller is
491 * hard-wired to use 8 dummy cycles, we must configure the device to also use 8
492 * cycles.
493 */
494static struct seq_rw_config n25q_read3_configs[] = {
495	{FLASH_FLAG_READ_1_4_4, SPINOR_OP_READ_1_4_4,	0, 4, 4, 0x00, 0, 8},
496	{FLASH_FLAG_READ_1_1_4, SPINOR_OP_READ_1_1_4,	0, 1, 4, 0x00, 0, 8},
497	{FLASH_FLAG_READ_1_2_2, SPINOR_OP_READ_1_2_2,	0, 2, 2, 0x00, 0, 8},
498	{FLASH_FLAG_READ_1_1_2, SPINOR_OP_READ_1_1_2,	0, 1, 2, 0x00, 0, 8},
499	{FLASH_FLAG_READ_FAST,	SPINOR_OP_READ_FAST,	0, 1, 1, 0x00, 0, 8},
500	{FLASH_FLAG_READ_WRITE, SPINOR_OP_READ,	        0, 1, 1, 0x00, 0, 0},
501	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
502};
503
504/* N25Q 4-byte Address READ configurations
505 *	- use special 4-byte address READ commands (reduces overheads, and
506 *        reduces risk of hitting watchdog reset issues).
507 *	- 'FAST' variants configured for 8 dummy cycles (see note above.)
508 */
509static struct seq_rw_config n25q_read4_configs[] = {
510	{FLASH_FLAG_READ_1_4_4, SPINOR_OP_READ4_1_4_4,	0, 4, 4, 0x00, 0, 8},
511	{FLASH_FLAG_READ_1_1_4, SPINOR_OP_READ4_1_1_4,	0, 1, 4, 0x00, 0, 8},
512	{FLASH_FLAG_READ_1_2_2, SPINOR_OP_READ4_1_2_2,	0, 2, 2, 0x00, 0, 8},
513	{FLASH_FLAG_READ_1_1_2, SPINOR_OP_READ4_1_1_2,	0, 1, 2, 0x00, 0, 8},
514	{FLASH_FLAG_READ_FAST,	SPINOR_OP_READ4_FAST,	0, 1, 1, 0x00, 0, 8},
515	{FLASH_FLAG_READ_WRITE, SPINOR_OP_READ4,	0, 1, 1, 0x00, 0, 0},
516	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
517};
518
519/*
520 * [MX25xxx] Configuration
521 */
522#define MX25_STATUS_QE			(0x1 << 6)
523
524static int stfsm_mx25_en_32bit_addr_seq(struct stfsm_seq *seq)
525{
526	seq->seq_opc[0] = (SEQ_OPC_PADS_1 |
527			   SEQ_OPC_CYCLES(8) |
528			   SEQ_OPC_OPCODE(SPINOR_OP_EN4B) |
529			   SEQ_OPC_CSDEASSERT);
530
531	seq->seq[0] = STFSM_INST_CMD1;
532	seq->seq[1] = STFSM_INST_WAIT;
533	seq->seq[2] = STFSM_INST_STOP;
534
535	seq->seq_cfg = (SEQ_CFG_PADS_1 |
536			SEQ_CFG_ERASE |
537			SEQ_CFG_READNOTWRITE |
538			SEQ_CFG_CSDEASSERT |
539			SEQ_CFG_STARTSEQ);
540
541	return 0;
542}
543
544/*
545 * [S25FLxxx] Configuration
546 */
547#define STFSM_S25FL_CONFIG_QE		(0x1 << 1)
548
549/*
550 * S25FLxxxS devices provide three ways of supporting 32-bit addressing: Bank
551 * Register, Extended Address Modes, and a 32-bit address command set.  The
552 * 32-bit address command set is used here, since it avoids any problems with
553 * entering a state that is incompatible with the SPIBoot Controller.
554 */
555static struct seq_rw_config stfsm_s25fl_read4_configs[] = {
556	{FLASH_FLAG_READ_1_4_4,  SPINOR_OP_READ4_1_4_4,  0, 4, 4, 0x00, 2, 4},
557	{FLASH_FLAG_READ_1_1_4,  SPINOR_OP_READ4_1_1_4,  0, 1, 4, 0x00, 0, 8},
558	{FLASH_FLAG_READ_1_2_2,  SPINOR_OP_READ4_1_2_2,  0, 2, 2, 0x00, 4, 0},
559	{FLASH_FLAG_READ_1_1_2,  SPINOR_OP_READ4_1_1_2,  0, 1, 2, 0x00, 0, 8},
560	{FLASH_FLAG_READ_FAST,   SPINOR_OP_READ4_FAST,   0, 1, 1, 0x00, 0, 8},
561	{FLASH_FLAG_READ_WRITE,  SPINOR_OP_READ4,        0, 1, 1, 0x00, 0, 0},
562	{0x00,                   0,                      0, 0, 0, 0x00, 0, 0},
563};
564
565static struct seq_rw_config stfsm_s25fl_write4_configs[] = {
566	{FLASH_FLAG_WRITE_1_1_4, S25FL_CMD_WRITE4_1_1_4, 1, 1, 4, 0x00, 0, 0},
567	{FLASH_FLAG_READ_WRITE,  S25FL_CMD_WRITE4,       1, 1, 1, 0x00, 0, 0},
568	{0x00,                   0,                      0, 0, 0, 0x00, 0, 0},
569};
570
571/*
572 * [W25Qxxx] Configuration
573 */
574#define W25Q_STATUS_QE			(0x1 << 1)
575
576static struct stfsm_seq stfsm_seq_read_jedec = {
577	.data_size = TRANSFER_SIZE(8),
578	.seq_opc[0] = (SEQ_OPC_PADS_1 |
579		       SEQ_OPC_CYCLES(8) |
580		       SEQ_OPC_OPCODE(SPINOR_OP_RDID)),
581	.seq = {
582		STFSM_INST_CMD1,
583		STFSM_INST_DATA_READ,
584		STFSM_INST_STOP,
585	},
586	.seq_cfg = (SEQ_CFG_PADS_1 |
587		    SEQ_CFG_READNOTWRITE |
588		    SEQ_CFG_CSDEASSERT |
589		    SEQ_CFG_STARTSEQ),
590};
591
592static struct stfsm_seq stfsm_seq_read_status_fifo = {
593	.data_size = TRANSFER_SIZE(4),
594	.seq_opc[0] = (SEQ_OPC_PADS_1 |
595		       SEQ_OPC_CYCLES(8) |
596		       SEQ_OPC_OPCODE(SPINOR_OP_RDSR)),
597	.seq = {
598		STFSM_INST_CMD1,
599		STFSM_INST_DATA_READ,
600		STFSM_INST_STOP,
601	},
602	.seq_cfg = (SEQ_CFG_PADS_1 |
603		    SEQ_CFG_READNOTWRITE |
604		    SEQ_CFG_CSDEASSERT |
605		    SEQ_CFG_STARTSEQ),
606};
607
608static struct stfsm_seq stfsm_seq_erase_sector = {
609	/* 'addr_cfg' configured during initialisation */
610	.seq_opc = {
611		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
612		 SEQ_OPC_OPCODE(SPINOR_OP_WREN) | SEQ_OPC_CSDEASSERT),
613
614		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
615		 SEQ_OPC_OPCODE(SPINOR_OP_SE)),
616	},
617	.seq = {
618		STFSM_INST_CMD1,
619		STFSM_INST_CMD2,
620		STFSM_INST_ADD1,
621		STFSM_INST_ADD2,
622		STFSM_INST_STOP,
623	},
624	.seq_cfg = (SEQ_CFG_PADS_1 |
625		    SEQ_CFG_READNOTWRITE |
626		    SEQ_CFG_CSDEASSERT |
627		    SEQ_CFG_STARTSEQ),
628};
629
630static struct stfsm_seq stfsm_seq_erase_chip = {
631	.seq_opc = {
632		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
633		 SEQ_OPC_OPCODE(SPINOR_OP_WREN) | SEQ_OPC_CSDEASSERT),
634
635		(SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
636		 SEQ_OPC_OPCODE(SPINOR_OP_CHIP_ERASE) | SEQ_OPC_CSDEASSERT),
637	},
638	.seq = {
639		STFSM_INST_CMD1,
640		STFSM_INST_CMD2,
641		STFSM_INST_WAIT,
642		STFSM_INST_STOP,
643	},
644	.seq_cfg = (SEQ_CFG_PADS_1 |
645		    SEQ_CFG_ERASE |
646		    SEQ_CFG_READNOTWRITE |
647		    SEQ_CFG_CSDEASSERT |
648		    SEQ_CFG_STARTSEQ),
649};
650
651static struct stfsm_seq stfsm_seq_write_status = {
652	.seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
653		       SEQ_OPC_OPCODE(SPINOR_OP_WREN) | SEQ_OPC_CSDEASSERT),
654	.seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
655		       SEQ_OPC_OPCODE(SPINOR_OP_WRSR)),
656	.seq = {
657		STFSM_INST_CMD1,
658		STFSM_INST_CMD2,
659		STFSM_INST_STA_WR1,
660		STFSM_INST_STOP,
661	},
662	.seq_cfg = (SEQ_CFG_PADS_1 |
663		    SEQ_CFG_READNOTWRITE |
664		    SEQ_CFG_CSDEASSERT |
665		    SEQ_CFG_STARTSEQ),
666};
667
668/* Dummy sequence to read one byte of data from flash into the FIFO */
669static const struct stfsm_seq stfsm_seq_load_fifo_byte = {
670	.data_size = TRANSFER_SIZE(1),
671	.seq_opc[0] = (SEQ_OPC_PADS_1 |
672		       SEQ_OPC_CYCLES(8) |
673		       SEQ_OPC_OPCODE(SPINOR_OP_RDID)),
674	.seq = {
675		STFSM_INST_CMD1,
676		STFSM_INST_DATA_READ,
677		STFSM_INST_STOP,
678	},
679	.seq_cfg = (SEQ_CFG_PADS_1 |
680		    SEQ_CFG_READNOTWRITE |
681		    SEQ_CFG_CSDEASSERT |
682		    SEQ_CFG_STARTSEQ),
683};
684
685static int stfsm_n25q_en_32bit_addr_seq(struct stfsm_seq *seq)
686{
687	seq->seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
688			   SEQ_OPC_OPCODE(SPINOR_OP_EN4B));
689	seq->seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
690			   SEQ_OPC_OPCODE(SPINOR_OP_WREN) |
691			   SEQ_OPC_CSDEASSERT);
692
693	seq->seq[0] = STFSM_INST_CMD2;
694	seq->seq[1] = STFSM_INST_CMD1;
695	seq->seq[2] = STFSM_INST_WAIT;
696	seq->seq[3] = STFSM_INST_STOP;
697
698	seq->seq_cfg = (SEQ_CFG_PADS_1 |
699			SEQ_CFG_ERASE |
700			SEQ_CFG_READNOTWRITE |
701			SEQ_CFG_CSDEASSERT |
702			SEQ_CFG_STARTSEQ);
703
704	return 0;
705}
706
707static inline int stfsm_is_idle(struct stfsm *fsm)
708{
709	return readl(fsm->base + SPI_FAST_SEQ_STA) & 0x10;
710}
711
712static inline uint32_t stfsm_fifo_available(struct stfsm *fsm)
713{
714	return (readl(fsm->base + SPI_FAST_SEQ_STA) >> 5) & 0x7f;
715}
716
717static inline void stfsm_load_seq(struct stfsm *fsm,
718				  const struct stfsm_seq *seq)
719{
720	void __iomem *dst = fsm->base + SPI_FAST_SEQ_TRANSFER_SIZE;
721	const uint32_t *src = (const uint32_t *)seq;
722	int words = sizeof(*seq) / sizeof(*src);
723
724	BUG_ON(!stfsm_is_idle(fsm));
725
726	while (words--) {
727		writel(*src, dst);
728		src++;
729		dst += 4;
730	}
731}
732
733static void stfsm_wait_seq(struct stfsm *fsm)
734{
735	unsigned long deadline;
736	int timeout = 0;
737
738	deadline = jiffies + msecs_to_jiffies(STFSM_MAX_WAIT_SEQ_MS);
739
740	while (!timeout) {
741		if (time_after_eq(jiffies, deadline))
742			timeout = 1;
743
744		if (stfsm_is_idle(fsm))
745			return;
746
747		cond_resched();
748	}
749
750	dev_err(fsm->dev, "timeout on sequence completion\n");
751}
752
753static void stfsm_read_fifo(struct stfsm *fsm, uint32_t *buf, uint32_t size)
754{
755	uint32_t remaining = size >> 2;
756	uint32_t avail;
757	uint32_t words;
758
759	dev_dbg(fsm->dev, "Reading %d bytes from FIFO\n", size);
760
761	BUG_ON((((uintptr_t)buf) & 0x3) || (size & 0x3));
762
763	while (remaining) {
764		for (;;) {
765			avail = stfsm_fifo_available(fsm);
766			if (avail)
767				break;
768			udelay(1);
769		}
770		words = min(avail, remaining);
771		remaining -= words;
772
773		readsl(fsm->base + SPI_FAST_SEQ_DATA_REG, buf, words);
774		buf += words;
775	}
776}
777
778/*
779 * Clear the data FIFO
780 *
781 * Typically, this is only required during driver initialisation, where no
782 * assumptions can be made regarding the state of the FIFO.
783 *
784 * The process of clearing the FIFO is complicated by fact that while it is
785 * possible for the FIFO to contain an arbitrary number of bytes [1], the
786 * SPI_FAST_SEQ_STA register only reports the number of complete 32-bit words
787 * present.  Furthermore, data can only be drained from the FIFO by reading
788 * complete 32-bit words.
789 *
790 * With this in mind, a two stage process is used to the clear the FIFO:
791 *
792 *     1. Read any complete 32-bit words from the FIFO, as reported by the
793 *        SPI_FAST_SEQ_STA register.
794 *
795 *     2. Mop up any remaining bytes.  At this point, it is not known if there
796 *        are 0, 1, 2, or 3 bytes in the FIFO.  To handle all cases, a dummy FSM
797 *        sequence is used to load one byte at a time, until a complete 32-bit
798 *        word is formed; at most, 4 bytes will need to be loaded.
799 *
800 * [1] It is theoretically possible for the FIFO to contain an arbitrary number
801 *     of bits.  However, since there are no known use-cases that leave
802 *     incomplete bytes in the FIFO, only words and bytes are considered here.
803 */
804static void stfsm_clear_fifo(struct stfsm *fsm)
805{
806	const struct stfsm_seq *seq = &stfsm_seq_load_fifo_byte;
807	uint32_t words, i;
808
809	/* 1. Clear any 32-bit words */
810	words = stfsm_fifo_available(fsm);
811	if (words) {
812		for (i = 0; i < words; i++)
813			readl(fsm->base + SPI_FAST_SEQ_DATA_REG);
814		dev_dbg(fsm->dev, "cleared %d words from FIFO\n", words);
815	}
816
817	/*
818	 * 2. Clear any remaining bytes
819	 *    - Load the FIFO, one byte at a time, until a complete 32-bit word
820	 *      is available.
821	 */
822	for (i = 0, words = 0; i < 4 && !words; i++) {
823		stfsm_load_seq(fsm, seq);
824		stfsm_wait_seq(fsm);
825		words = stfsm_fifo_available(fsm);
826	}
827
828	/*    - A single word must be available now */
829	if (words != 1) {
830		dev_err(fsm->dev, "failed to clear bytes from the data FIFO\n");
831		return;
832	}
833
834	/*    - Read the 32-bit word */
835	readl(fsm->base + SPI_FAST_SEQ_DATA_REG);
836
837	dev_dbg(fsm->dev, "cleared %d byte(s) from the data FIFO\n", 4 - i);
838}
839
840static int stfsm_write_fifo(struct stfsm *fsm, const uint32_t *buf,
841			    uint32_t size)
842{
843	uint32_t words = size >> 2;
844
845	dev_dbg(fsm->dev, "writing %d bytes to FIFO\n", size);
846
847	BUG_ON((((uintptr_t)buf) & 0x3) || (size & 0x3));
848
849	writesl(fsm->base + SPI_FAST_SEQ_DATA_REG, buf, words);
850
851	return size;
852}
853
854static int stfsm_enter_32bit_addr(struct stfsm *fsm, int enter)
855{
856	struct stfsm_seq *seq = &fsm->stfsm_seq_en_32bit_addr;
857	uint32_t cmd = enter ? SPINOR_OP_EN4B : SPINOR_OP_EX4B;
858
859	seq->seq_opc[0] = (SEQ_OPC_PADS_1 |
860			   SEQ_OPC_CYCLES(8) |
861			   SEQ_OPC_OPCODE(cmd) |
862			   SEQ_OPC_CSDEASSERT);
863
864	stfsm_load_seq(fsm, seq);
865
866	stfsm_wait_seq(fsm);
867
868	return 0;
869}
870
871static uint8_t stfsm_wait_busy(struct stfsm *fsm)
872{
873	struct stfsm_seq *seq = &stfsm_seq_read_status_fifo;
874	unsigned long deadline;
875	uint32_t status;
876	int timeout = 0;
877
878	/* Use RDRS1 */
879	seq->seq_opc[0] = (SEQ_OPC_PADS_1 |
880			   SEQ_OPC_CYCLES(8) |
881			   SEQ_OPC_OPCODE(SPINOR_OP_RDSR));
882
883	/* Load read_status sequence */
884	stfsm_load_seq(fsm, seq);
885
886	/*
887	 * Repeat until busy bit is deasserted, or timeout, or error (S25FLxxxS)
888	 */
889	deadline = jiffies + FLASH_MAX_BUSY_WAIT;
890	while (!timeout) {
891		if (time_after_eq(jiffies, deadline))
892			timeout = 1;
893
894		stfsm_wait_seq(fsm);
895
896		stfsm_read_fifo(fsm, &status, 4);
897
898		if ((status & FLASH_STATUS_BUSY) == 0)
899			return 0;
900
901		if ((fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS) &&
902		    ((status & S25FL_STATUS_P_ERR) ||
903		     (status & S25FL_STATUS_E_ERR)))
904			return (uint8_t)(status & 0xff);
905
906		if (!timeout)
907			/* Restart */
908			writel(seq->seq_cfg, fsm->base + SPI_FAST_SEQ_CFG);
909
910		cond_resched();
911	}
912
913	dev_err(fsm->dev, "timeout on wait_busy\n");
914
915	return FLASH_STATUS_TIMEOUT;
916}
917
918static int stfsm_read_status(struct stfsm *fsm, uint8_t cmd,
919			     uint8_t *data, int bytes)
920{
921	struct stfsm_seq *seq = &stfsm_seq_read_status_fifo;
922	uint32_t tmp;
923	uint8_t *t = (uint8_t *)&tmp;
924	int i;
925
926	dev_dbg(fsm->dev, "read 'status' register [0x%02x], %d byte(s)\n",
927		cmd, bytes);
928
929	BUG_ON(bytes != 1 && bytes != 2);
930
931	seq->seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
932			   SEQ_OPC_OPCODE(cmd)),
933
934	stfsm_load_seq(fsm, seq);
935
936	stfsm_read_fifo(fsm, &tmp, 4);
937
938	for (i = 0; i < bytes; i++)
939		data[i] = t[i];
940
941	stfsm_wait_seq(fsm);
942
943	return 0;
944}
945
946static int stfsm_write_status(struct stfsm *fsm, uint8_t cmd,
947			    uint16_t data, int bytes, int wait_busy)
948{
949	struct stfsm_seq *seq = &stfsm_seq_write_status;
950
951	dev_dbg(fsm->dev,
952		"write 'status' register [0x%02x], %d byte(s), 0x%04x\n"
953		" %s wait-busy\n", cmd, bytes, data, wait_busy ? "with" : "no");
954
955	BUG_ON(bytes != 1 && bytes != 2);
956
957	seq->seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
958			   SEQ_OPC_OPCODE(cmd));
959
960	seq->status = (uint32_t)data | STA_PADS_1 | STA_CSDEASSERT;
961	seq->seq[2] = (bytes == 1) ? STFSM_INST_STA_WR1 : STFSM_INST_STA_WR1_2;
962
963	stfsm_load_seq(fsm, seq);
964
965	stfsm_wait_seq(fsm);
966
967	if (wait_busy)
968		stfsm_wait_busy(fsm);
969
970	return 0;
971}
972
973/*
974 * SoC reset on 'boot-from-spi' systems
975 *
976 * Certain modes of operation cause the Flash device to enter a particular state
977 * for a period of time (e.g. 'Erase Sector', 'Quad Enable', and 'Enter 32-bit
978 * Addr' commands).  On boot-from-spi systems, it is important to consider what
979 * happens if a warm reset occurs during this period.  The SPIBoot controller
980 * assumes that Flash device is in its default reset state, 24-bit address mode,
981 * and ready to accept commands.  This can be achieved using some form of
982 * on-board logic/controller to force a device POR in response to a SoC-level
983 * reset or by making use of the device reset signal if available (limited
984 * number of devices only).
985 *
986 * Failure to take such precautions can cause problems following a warm reset.
987 * For some operations (e.g. ERASE), there is little that can be done.  For
988 * other modes of operation (e.g. 32-bit addressing), options are often
989 * available that can help minimise the window in which a reset could cause a
990 * problem.
991 *
992 */
993static bool stfsm_can_handle_soc_reset(struct stfsm *fsm)
994{
995	/* Reset signal is available on the board and supported by the device */
996	if (fsm->reset_signal && fsm->info->flags & FLASH_FLAG_RESET)
997		return true;
998
999	/* Board-level logic forces a power-on-reset */
1000	if (fsm->reset_por)
1001		return true;
1002
1003	/* Reset is not properly handled and may result in failure to reboot */
1004	return false;
1005}
1006
1007/* Configure 'addr_cfg' according to addressing mode */
1008static void stfsm_prepare_erasesec_seq(struct stfsm *fsm,
1009				       struct stfsm_seq *seq)
1010{
1011	int addr1_cycles = fsm->info->flags & FLASH_FLAG_32BIT_ADDR ? 16 : 8;
1012
1013	seq->addr_cfg = (ADR_CFG_CYCLES_ADD1(addr1_cycles) |
1014			 ADR_CFG_PADS_1_ADD1 |
1015			 ADR_CFG_CYCLES_ADD2(16) |
1016			 ADR_CFG_PADS_1_ADD2 |
1017			 ADR_CFG_CSDEASSERT_ADD2);
1018}
1019
1020/* Search for preferred configuration based on available flags */
1021static struct seq_rw_config *
1022stfsm_search_seq_rw_configs(struct stfsm *fsm,
1023			    struct seq_rw_config cfgs[])
1024{
1025	struct seq_rw_config *config;
1026	int flags = fsm->info->flags;
1027
1028	for (config = cfgs; config->cmd != 0; config++)
1029		if ((config->flags & flags) == config->flags)
1030			return config;
1031
1032	return NULL;
1033}
1034
1035/* Prepare a READ/WRITE sequence according to configuration parameters */
1036static void stfsm_prepare_rw_seq(struct stfsm *fsm,
1037				 struct stfsm_seq *seq,
1038				 struct seq_rw_config *cfg)
1039{
1040	int addr1_cycles, addr2_cycles;
1041	int i = 0;
1042
1043	memset(seq, 0, sizeof(*seq));
1044
1045	/* Add READ/WRITE OPC  */
1046	seq->seq_opc[i++] = (SEQ_OPC_PADS_1 |
1047			     SEQ_OPC_CYCLES(8) |
1048			     SEQ_OPC_OPCODE(cfg->cmd));
1049
1050	/* Add WREN OPC for a WRITE sequence */
1051	if (cfg->write)
1052		seq->seq_opc[i++] = (SEQ_OPC_PADS_1 |
1053				     SEQ_OPC_CYCLES(8) |
1054				     SEQ_OPC_OPCODE(SPINOR_OP_WREN) |
1055				     SEQ_OPC_CSDEASSERT);
1056
1057	/* Address configuration (24 or 32-bit addresses) */
1058	addr1_cycles  = (fsm->info->flags & FLASH_FLAG_32BIT_ADDR) ? 16 : 8;
1059	addr1_cycles /= cfg->addr_pads;
1060	addr2_cycles  = 16 / cfg->addr_pads;
1061	seq->addr_cfg = ((addr1_cycles & 0x3f) << 0 |	/* ADD1 cycles */
1062			 (cfg->addr_pads - 1) << 6 |	/* ADD1 pads */
1063			 (addr2_cycles & 0x3f) << 16 |	/* ADD2 cycles */
1064			 ((cfg->addr_pads - 1) << 22));	/* ADD2 pads */
1065
1066	/* Data/Sequence configuration */
1067	seq->seq_cfg = ((cfg->data_pads - 1) << 16 |
1068			SEQ_CFG_STARTSEQ |
1069			SEQ_CFG_CSDEASSERT);
1070	if (!cfg->write)
1071		seq->seq_cfg |= SEQ_CFG_READNOTWRITE;
1072
1073	/* Mode configuration (no. of pads taken from addr cfg) */
1074	seq->mode = ((cfg->mode_data & 0xff) << 0 |	/* data */
1075		     (cfg->mode_cycles & 0x3f) << 16 |	/* cycles */
1076		     (cfg->addr_pads - 1) << 22);	/* pads */
1077
1078	/* Dummy configuration (no. of pads taken from addr cfg) */
1079	seq->dummy = ((cfg->dummy_cycles & 0x3f) << 16 |	/* cycles */
1080		      (cfg->addr_pads - 1) << 22);		/* pads */
1081
1082
1083	/* Instruction sequence */
1084	i = 0;
1085	if (cfg->write)
1086		seq->seq[i++] = STFSM_INST_CMD2;
1087
1088	seq->seq[i++] = STFSM_INST_CMD1;
1089
1090	seq->seq[i++] = STFSM_INST_ADD1;
1091	seq->seq[i++] = STFSM_INST_ADD2;
1092
1093	if (cfg->mode_cycles)
1094		seq->seq[i++] = STFSM_INST_MODE;
1095
1096	if (cfg->dummy_cycles)
1097		seq->seq[i++] = STFSM_INST_DUMMY;
1098
1099	seq->seq[i++] =
1100		cfg->write ? STFSM_INST_DATA_WRITE : STFSM_INST_DATA_READ;
1101	seq->seq[i++] = STFSM_INST_STOP;
1102}
1103
1104static int stfsm_search_prepare_rw_seq(struct stfsm *fsm,
1105				       struct stfsm_seq *seq,
1106				       struct seq_rw_config *cfgs)
1107{
1108	struct seq_rw_config *config;
1109
1110	config = stfsm_search_seq_rw_configs(fsm, cfgs);
1111	if (!config) {
1112		dev_err(fsm->dev, "failed to find suitable config\n");
1113		return -EINVAL;
1114	}
1115
1116	stfsm_prepare_rw_seq(fsm, seq, config);
1117
1118	return 0;
1119}
1120
1121/* Prepare a READ/WRITE/ERASE 'default' sequences */
1122static int stfsm_prepare_rwe_seqs_default(struct stfsm *fsm)
1123{
1124	uint32_t flags = fsm->info->flags;
1125	int ret;
1126
1127	/* Configure 'READ' sequence */
1128	ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1129					  default_read_configs);
1130	if (ret) {
1131		dev_err(fsm->dev,
1132			"failed to prep READ sequence with flags [0x%08x]\n",
1133			flags);
1134		return ret;
1135	}
1136
1137	/* Configure 'WRITE' sequence */
1138	ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_write,
1139					  default_write_configs);
1140	if (ret) {
1141		dev_err(fsm->dev,
1142			"failed to prep WRITE sequence with flags [0x%08x]\n",
1143			flags);
1144		return ret;
1145	}
1146
1147	/* Configure 'ERASE_SECTOR' sequence */
1148	stfsm_prepare_erasesec_seq(fsm, &stfsm_seq_erase_sector);
1149
1150	return 0;
1151}
1152
1153static int stfsm_mx25_config(struct stfsm *fsm)
1154{
1155	uint32_t flags = fsm->info->flags;
1156	uint32_t data_pads;
1157	uint8_t sta;
1158	int ret;
1159	bool soc_reset;
1160
1161	/*
1162	 * Use default READ/WRITE sequences
1163	 */
1164	ret = stfsm_prepare_rwe_seqs_default(fsm);
1165	if (ret)
1166		return ret;
1167
1168	/*
1169	 * Configure 32-bit Address Support
1170	 */
1171	if (flags & FLASH_FLAG_32BIT_ADDR) {
1172		/* Configure 'enter_32bitaddr' FSM sequence */
1173		stfsm_mx25_en_32bit_addr_seq(&fsm->stfsm_seq_en_32bit_addr);
1174
1175		soc_reset = stfsm_can_handle_soc_reset(fsm);
1176		if (soc_reset || !fsm->booted_from_spi)
1177			/* If we can handle SoC resets, we enable 32-bit address
1178			 * mode pervasively */
1179			stfsm_enter_32bit_addr(fsm, 1);
1180
1181		else
1182			/* Else, enable/disable 32-bit addressing before/after
1183			 * each operation */
1184			fsm->configuration = (CFG_READ_TOGGLE_32BIT_ADDR |
1185					      CFG_WRITE_TOGGLE_32BIT_ADDR |
1186					      CFG_ERASESEC_TOGGLE_32BIT_ADDR);
1187	}
1188
1189	/* Check status of 'QE' bit, update if required. */
1190	stfsm_read_status(fsm, SPINOR_OP_RDSR, &sta, 1);
1191	data_pads = ((fsm->stfsm_seq_read.seq_cfg >> 16) & 0x3) + 1;
1192	if (data_pads == 4) {
1193		if (!(sta & MX25_STATUS_QE)) {
1194			/* Set 'QE' */
1195			sta |= MX25_STATUS_QE;
1196
1197			stfsm_write_status(fsm, SPINOR_OP_WRSR, sta, 1, 1);
1198		}
1199	} else {
1200		if (sta & MX25_STATUS_QE) {
1201			/* Clear 'QE' */
1202			sta &= ~MX25_STATUS_QE;
1203
1204			stfsm_write_status(fsm, SPINOR_OP_WRSR, sta, 1, 1);
1205		}
1206	}
1207
1208	return 0;
1209}
1210
1211static int stfsm_n25q_config(struct stfsm *fsm)
1212{
1213	uint32_t flags = fsm->info->flags;
1214	uint8_t vcr;
1215	int ret = 0;
1216	bool soc_reset;
1217
1218	/* Configure 'READ' sequence */
1219	if (flags & FLASH_FLAG_32BIT_ADDR)
1220		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1221						  n25q_read4_configs);
1222	else
1223		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1224						  n25q_read3_configs);
1225	if (ret) {
1226		dev_err(fsm->dev,
1227			"failed to prepare READ sequence with flags [0x%08x]\n",
1228			flags);
1229		return ret;
1230	}
1231
1232	/* Configure 'WRITE' sequence (default configs) */
1233	ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_write,
1234					  default_write_configs);
1235	if (ret) {
1236		dev_err(fsm->dev,
1237			"preparing WRITE sequence using flags [0x%08x] failed\n",
1238			flags);
1239		return ret;
1240	}
1241
1242	/* * Configure 'ERASE_SECTOR' sequence */
1243	stfsm_prepare_erasesec_seq(fsm, &stfsm_seq_erase_sector);
1244
1245	/* Configure 32-bit address support */
1246	if (flags & FLASH_FLAG_32BIT_ADDR) {
1247		stfsm_n25q_en_32bit_addr_seq(&fsm->stfsm_seq_en_32bit_addr);
1248
1249		soc_reset = stfsm_can_handle_soc_reset(fsm);
1250		if (soc_reset || !fsm->booted_from_spi) {
1251			/*
1252			 * If we can handle SoC resets, we enable 32-bit
1253			 * address mode pervasively
1254			 */
1255			stfsm_enter_32bit_addr(fsm, 1);
1256		} else {
1257			/*
1258			 * If not, enable/disable for WRITE and ERASE
1259			 * operations (READ uses special commands)
1260			 */
1261			fsm->configuration = (CFG_WRITE_TOGGLE_32BIT_ADDR |
1262					      CFG_ERASESEC_TOGGLE_32BIT_ADDR);
1263		}
1264	}
1265
1266	/*
1267	 * Configure device to use 8 dummy cycles
1268	 */
1269	vcr = (N25Q_VCR_DUMMY_CYCLES(8) | N25Q_VCR_XIP_DISABLED |
1270	       N25Q_VCR_WRAP_CONT);
1271	stfsm_write_status(fsm, N25Q_CMD_WRVCR, vcr, 1, 0);
1272
1273	return 0;
1274}
1275
1276static void stfsm_s25fl_prepare_erasesec_seq_32(struct stfsm_seq *seq)
1277{
1278	seq->seq_opc[1] = (SEQ_OPC_PADS_1 |
1279			   SEQ_OPC_CYCLES(8) |
1280			   SEQ_OPC_OPCODE(S25FL_CMD_SE4));
1281
1282	seq->addr_cfg = (ADR_CFG_CYCLES_ADD1(16) |
1283			 ADR_CFG_PADS_1_ADD1 |
1284			 ADR_CFG_CYCLES_ADD2(16) |
1285			 ADR_CFG_PADS_1_ADD2 |
1286			 ADR_CFG_CSDEASSERT_ADD2);
1287}
1288
1289static void stfsm_s25fl_read_dyb(struct stfsm *fsm, uint32_t offs, uint8_t *dby)
1290{
1291	uint32_t tmp;
1292	struct stfsm_seq seq = {
1293		.data_size = TRANSFER_SIZE(4),
1294		.seq_opc[0] = (SEQ_OPC_PADS_1 |
1295			       SEQ_OPC_CYCLES(8) |
1296			       SEQ_OPC_OPCODE(S25FL_CMD_DYBRD)),
1297		.addr_cfg = (ADR_CFG_CYCLES_ADD1(16) |
1298			     ADR_CFG_PADS_1_ADD1 |
1299			     ADR_CFG_CYCLES_ADD2(16) |
1300			     ADR_CFG_PADS_1_ADD2),
1301		.addr1 = (offs >> 16) & 0xffff,
1302		.addr2 = offs & 0xffff,
1303		.seq = {
1304			STFSM_INST_CMD1,
1305			STFSM_INST_ADD1,
1306			STFSM_INST_ADD2,
1307			STFSM_INST_DATA_READ,
1308			STFSM_INST_STOP,
1309		},
1310		.seq_cfg = (SEQ_CFG_PADS_1 |
1311			    SEQ_CFG_READNOTWRITE |
1312			    SEQ_CFG_CSDEASSERT |
1313			    SEQ_CFG_STARTSEQ),
1314	};
1315
1316	stfsm_load_seq(fsm, &seq);
1317
1318	stfsm_read_fifo(fsm, &tmp, 4);
1319
1320	*dby = (uint8_t)(tmp >> 24);
1321
1322	stfsm_wait_seq(fsm);
1323}
1324
1325static void stfsm_s25fl_write_dyb(struct stfsm *fsm, uint32_t offs, uint8_t dby)
1326{
1327	struct stfsm_seq seq = {
1328		.seq_opc[0] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
1329			       SEQ_OPC_OPCODE(SPINOR_OP_WREN) |
1330			       SEQ_OPC_CSDEASSERT),
1331		.seq_opc[1] = (SEQ_OPC_PADS_1 | SEQ_OPC_CYCLES(8) |
1332			       SEQ_OPC_OPCODE(S25FL_CMD_DYBWR)),
1333		.addr_cfg = (ADR_CFG_CYCLES_ADD1(16) |
1334			     ADR_CFG_PADS_1_ADD1 |
1335			     ADR_CFG_CYCLES_ADD2(16) |
1336			     ADR_CFG_PADS_1_ADD2),
1337		.status = (uint32_t)dby | STA_PADS_1 | STA_CSDEASSERT,
1338		.addr1 = (offs >> 16) & 0xffff,
1339		.addr2 = offs & 0xffff,
1340		.seq = {
1341			STFSM_INST_CMD1,
1342			STFSM_INST_CMD2,
1343			STFSM_INST_ADD1,
1344			STFSM_INST_ADD2,
1345			STFSM_INST_STA_WR1,
1346			STFSM_INST_STOP,
1347		},
1348		.seq_cfg = (SEQ_CFG_PADS_1 |
1349			    SEQ_CFG_READNOTWRITE |
1350			    SEQ_CFG_CSDEASSERT |
1351			    SEQ_CFG_STARTSEQ),
1352	};
1353
1354	stfsm_load_seq(fsm, &seq);
1355	stfsm_wait_seq(fsm);
1356
1357	stfsm_wait_busy(fsm);
1358}
1359
1360static int stfsm_s25fl_clear_status_reg(struct stfsm *fsm)
1361{
1362	struct stfsm_seq seq = {
1363		.seq_opc[0] = (SEQ_OPC_PADS_1 |
1364			       SEQ_OPC_CYCLES(8) |
1365			       SEQ_OPC_OPCODE(S25FL_CMD_CLSR) |
1366			       SEQ_OPC_CSDEASSERT),
1367		.seq_opc[1] = (SEQ_OPC_PADS_1 |
1368			       SEQ_OPC_CYCLES(8) |
1369			       SEQ_OPC_OPCODE(SPINOR_OP_WRDI) |
1370			       SEQ_OPC_CSDEASSERT),
1371		.seq = {
1372			STFSM_INST_CMD1,
1373			STFSM_INST_CMD2,
1374			STFSM_INST_WAIT,
1375			STFSM_INST_STOP,
1376		},
1377		.seq_cfg = (SEQ_CFG_PADS_1 |
1378			    SEQ_CFG_ERASE |
1379			    SEQ_CFG_READNOTWRITE |
1380			    SEQ_CFG_CSDEASSERT |
1381			    SEQ_CFG_STARTSEQ),
1382	};
1383
1384	stfsm_load_seq(fsm, &seq);
1385
1386	stfsm_wait_seq(fsm);
1387
1388	return 0;
1389}
1390
1391static int stfsm_s25fl_config(struct stfsm *fsm)
1392{
1393	struct flash_info *info = fsm->info;
1394	uint32_t flags = info->flags;
1395	uint32_t data_pads;
1396	uint32_t offs;
1397	uint16_t sta_wr;
1398	uint8_t sr1, cr1, dyb;
1399	int update_sr = 0;
1400	int ret;
1401
1402	if (flags & FLASH_FLAG_32BIT_ADDR) {
1403		/*
1404		 * Prepare Read/Write/Erase sequences according to S25FLxxx
1405		 * 32-bit address command set
1406		 */
1407		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
1408						  stfsm_s25fl_read4_configs);
1409		if (ret)
1410			return ret;
1411
1412		ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_write,
1413						  stfsm_s25fl_write4_configs);
1414		if (ret)
1415			return ret;
1416
1417		stfsm_s25fl_prepare_erasesec_seq_32(&stfsm_seq_erase_sector);
1418
1419	} else {
1420		/* Use default configurations for 24-bit addressing */
1421		ret = stfsm_prepare_rwe_seqs_default(fsm);
1422		if (ret)
1423			return ret;
1424	}
1425
1426	/*
1427	 * For devices that support 'DYB' sector locking, check lock status and
1428	 * unlock sectors if necessary (some variants power-on with sectors
1429	 * locked by default)
1430	 */
1431	if (flags & FLASH_FLAG_DYB_LOCKING) {
1432		offs = 0;
1433		for (offs = 0; offs < info->sector_size * info->n_sectors;) {
1434			stfsm_s25fl_read_dyb(fsm, offs, &dyb);
1435			if (dyb == 0x00)
1436				stfsm_s25fl_write_dyb(fsm, offs, 0xff);
1437
1438			/* Handle bottom/top 4KiB parameter sectors */
1439			if ((offs < info->sector_size * 2) ||
1440			    (offs >= (info->sector_size - info->n_sectors * 4)))
1441				offs += 0x1000;
1442			else
1443				offs += 0x10000;
1444		}
1445	}
1446
1447	/* Check status of 'QE' bit, update if required. */
1448	stfsm_read_status(fsm, SPINOR_OP_RDSR2, &cr1, 1);
1449	data_pads = ((fsm->stfsm_seq_read.seq_cfg >> 16) & 0x3) + 1;
1450	if (data_pads == 4) {
1451		if (!(cr1 & STFSM_S25FL_CONFIG_QE)) {
1452			/* Set 'QE' */
1453			cr1 |= STFSM_S25FL_CONFIG_QE;
1454
1455			update_sr = 1;
1456		}
1457	} else {
1458		if (cr1 & STFSM_S25FL_CONFIG_QE) {
1459			/* Clear 'QE' */
1460			cr1 &= ~STFSM_S25FL_CONFIG_QE;
1461
1462			update_sr = 1;
1463		}
1464	}
1465	if (update_sr) {
1466		stfsm_read_status(fsm, SPINOR_OP_RDSR, &sr1, 1);
1467		sta_wr = ((uint16_t)cr1  << 8) | sr1;
1468		stfsm_write_status(fsm, SPINOR_OP_WRSR, sta_wr, 2, 1);
1469	}
1470
1471	/*
1472	 * S25FLxxx devices support Program and Error error flags.
1473	 * Configure driver to check flags and clear if necessary.
1474	 */
1475	fsm->configuration |= CFG_S25FL_CHECK_ERROR_FLAGS;
1476
1477	return 0;
1478}
1479
1480static int stfsm_w25q_config(struct stfsm *fsm)
1481{
1482	uint32_t data_pads;
1483	uint8_t sr1, sr2;
1484	uint16_t sr_wr;
1485	int update_sr = 0;
1486	int ret;
1487
1488	ret = stfsm_prepare_rwe_seqs_default(fsm);
1489	if (ret)
1490		return ret;
1491
1492	/* Check status of 'QE' bit, update if required. */
1493	stfsm_read_status(fsm, SPINOR_OP_RDSR2, &sr2, 1);
1494	data_pads = ((fsm->stfsm_seq_read.seq_cfg >> 16) & 0x3) + 1;
1495	if (data_pads == 4) {
1496		if (!(sr2 & W25Q_STATUS_QE)) {
1497			/* Set 'QE' */
1498			sr2 |= W25Q_STATUS_QE;
1499			update_sr = 1;
1500		}
1501	} else {
1502		if (sr2 & W25Q_STATUS_QE) {
1503			/* Clear 'QE' */
1504			sr2 &= ~W25Q_STATUS_QE;
1505			update_sr = 1;
1506		}
1507	}
1508	if (update_sr) {
1509		/* Write status register */
1510		stfsm_read_status(fsm, SPINOR_OP_RDSR, &sr1, 1);
1511		sr_wr = ((uint16_t)sr2 << 8) | sr1;
1512		stfsm_write_status(fsm, SPINOR_OP_WRSR, sr_wr, 2, 1);
1513	}
1514
1515	return 0;
1516}
1517
1518static int stfsm_read(struct stfsm *fsm, uint8_t *buf, uint32_t size,
1519		      uint32_t offset)
1520{
1521	struct stfsm_seq *seq = &fsm->stfsm_seq_read;
1522	uint32_t data_pads;
1523	uint32_t read_mask;
1524	uint32_t size_ub;
1525	uint32_t size_lb;
1526	uint32_t size_mop;
1527	uint32_t tmp[4];
1528	uint32_t page_buf[FLASH_PAGESIZE_32];
1529	uint8_t *p;
1530
1531	dev_dbg(fsm->dev, "reading %d bytes from 0x%08x\n", size, offset);
1532
1533	/* Enter 32-bit address mode, if required */
1534	if (fsm->configuration & CFG_READ_TOGGLE_32BIT_ADDR)
1535		stfsm_enter_32bit_addr(fsm, 1);
1536
1537	/* Must read in multiples of 32 cycles (or 32*pads/8 Bytes) */
1538	data_pads = ((seq->seq_cfg >> 16) & 0x3) + 1;
1539	read_mask = (data_pads << 2) - 1;
1540
1541	/* Handle non-aligned buf */
1542	p = ((uintptr_t)buf & 0x3) ? (uint8_t *)page_buf : buf;
1543
1544	/* Handle non-aligned size */
1545	size_ub = (size + read_mask) & ~read_mask;
1546	size_lb = size & ~read_mask;
1547	size_mop = size & read_mask;
1548
1549	seq->data_size = TRANSFER_SIZE(size_ub);
1550	seq->addr1 = (offset >> 16) & 0xffff;
1551	seq->addr2 = offset & 0xffff;
1552
1553	stfsm_load_seq(fsm, seq);
1554
1555	if (size_lb)
1556		stfsm_read_fifo(fsm, (uint32_t *)p, size_lb);
1557
1558	if (size_mop) {
1559		stfsm_read_fifo(fsm, tmp, read_mask + 1);
1560		memcpy(p + size_lb, &tmp, size_mop);
1561	}
1562
1563	/* Handle non-aligned buf */
1564	if ((uintptr_t)buf & 0x3)
1565		memcpy(buf, page_buf, size);
1566
1567	/* Wait for sequence to finish */
1568	stfsm_wait_seq(fsm);
1569
1570	stfsm_clear_fifo(fsm);
1571
1572	/* Exit 32-bit address mode, if required */
1573	if (fsm->configuration & CFG_READ_TOGGLE_32BIT_ADDR)
1574		stfsm_enter_32bit_addr(fsm, 0);
1575
1576	return 0;
1577}
1578
1579static int stfsm_write(struct stfsm *fsm, const uint8_t *buf,
1580		       uint32_t size, uint32_t offset)
1581{
1582	struct stfsm_seq *seq = &fsm->stfsm_seq_write;
1583	uint32_t data_pads;
1584	uint32_t write_mask;
1585	uint32_t size_ub;
1586	uint32_t size_lb;
1587	uint32_t size_mop;
1588	uint32_t tmp[4];
1589	uint32_t i;
1590	uint32_t page_buf[FLASH_PAGESIZE_32];
1591	uint8_t *t = (uint8_t *)&tmp;
1592	const uint8_t *p;
1593	int ret;
1594
1595	dev_dbg(fsm->dev, "writing %d bytes to 0x%08x\n", size, offset);
1596
1597	/* Enter 32-bit address mode, if required */
1598	if (fsm->configuration & CFG_WRITE_TOGGLE_32BIT_ADDR)
1599		stfsm_enter_32bit_addr(fsm, 1);
1600
1601	/* Must write in multiples of 32 cycles (or 32*pads/8 bytes) */
1602	data_pads = ((seq->seq_cfg >> 16) & 0x3) + 1;
1603	write_mask = (data_pads << 2) - 1;
1604
1605	/* Handle non-aligned buf */
1606	if ((uintptr_t)buf & 0x3) {
1607		memcpy(page_buf, buf, size);
1608		p = (uint8_t *)page_buf;
1609	} else {
1610		p = buf;
1611	}
1612
1613	/* Handle non-aligned size */
1614	size_ub = (size + write_mask) & ~write_mask;
1615	size_lb = size & ~write_mask;
1616	size_mop = size & write_mask;
1617
1618	seq->data_size = TRANSFER_SIZE(size_ub);
1619	seq->addr1 = (offset >> 16) & 0xffff;
1620	seq->addr2 = offset & 0xffff;
1621
1622	/* Need to set FIFO to write mode, before writing data to FIFO (see
1623	 * GNBvb79594)
1624	 */
1625	writel(0x00040000, fsm->base + SPI_FAST_SEQ_CFG);
1626
1627	/*
1628	 * Before writing data to the FIFO, apply a small delay to allow a
1629	 * potential change of FIFO direction to complete.
1630	 */
1631	if (fsm->fifo_dir_delay == 0)
1632		readl(fsm->base + SPI_FAST_SEQ_CFG);
1633	else
1634		udelay(fsm->fifo_dir_delay);
1635
1636
1637	/* Write data to FIFO, before starting sequence (see GNBvd79593) */
1638	if (size_lb) {
1639		stfsm_write_fifo(fsm, (uint32_t *)p, size_lb);
1640		p += size_lb;
1641	}
1642
1643	/* Handle non-aligned size */
1644	if (size_mop) {
1645		memset(t, 0xff, write_mask + 1);	/* fill with 0xff's */
1646		for (i = 0; i < size_mop; i++)
1647			t[i] = *p++;
1648
1649		stfsm_write_fifo(fsm, tmp, write_mask + 1);
1650	}
1651
1652	/* Start sequence */
1653	stfsm_load_seq(fsm, seq);
1654
1655	/* Wait for sequence to finish */
1656	stfsm_wait_seq(fsm);
1657
1658	/* Wait for completion */
1659	ret = stfsm_wait_busy(fsm);
1660	if (ret && fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS)
1661		stfsm_s25fl_clear_status_reg(fsm);
1662
1663	/* Exit 32-bit address mode, if required */
1664	if (fsm->configuration & CFG_WRITE_TOGGLE_32BIT_ADDR)
1665		stfsm_enter_32bit_addr(fsm, 0);
1666
1667	return 0;
1668}
1669
1670/*
1671 * Read an address range from the flash chip. The address range
1672 * may be any size provided it is within the physical boundaries.
1673 */
1674static int stfsm_mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
1675			  size_t *retlen, u_char *buf)
1676{
1677	struct stfsm *fsm = dev_get_drvdata(mtd->dev.parent);
1678	uint32_t bytes;
1679
1680	dev_dbg(fsm->dev, "%s from 0x%08x, len %zd\n",
1681		__func__, (u32)from, len);
1682
1683	mutex_lock(&fsm->lock);
1684
1685	while (len > 0) {
1686		bytes = min_t(size_t, len, FLASH_PAGESIZE);
1687
1688		stfsm_read(fsm, buf, bytes, from);
1689
1690		buf += bytes;
1691		from += bytes;
1692		len -= bytes;
1693
1694		*retlen += bytes;
1695	}
1696
1697	mutex_unlock(&fsm->lock);
1698
1699	return 0;
1700}
1701
1702static int stfsm_erase_sector(struct stfsm *fsm, uint32_t offset)
1703{
1704	struct stfsm_seq *seq = &stfsm_seq_erase_sector;
1705	int ret;
1706
1707	dev_dbg(fsm->dev, "erasing sector at 0x%08x\n", offset);
1708
1709	/* Enter 32-bit address mode, if required */
1710	if (fsm->configuration & CFG_ERASESEC_TOGGLE_32BIT_ADDR)
1711		stfsm_enter_32bit_addr(fsm, 1);
1712
1713	seq->addr1 = (offset >> 16) & 0xffff;
1714	seq->addr2 = offset & 0xffff;
1715
1716	stfsm_load_seq(fsm, seq);
1717
1718	stfsm_wait_seq(fsm);
1719
1720	/* Wait for completion */
1721	ret = stfsm_wait_busy(fsm);
1722	if (ret && fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS)
1723		stfsm_s25fl_clear_status_reg(fsm);
1724
1725	/* Exit 32-bit address mode, if required */
1726	if (fsm->configuration & CFG_ERASESEC_TOGGLE_32BIT_ADDR)
1727		stfsm_enter_32bit_addr(fsm, 0);
1728
1729	return ret;
1730}
1731
1732static int stfsm_erase_chip(struct stfsm *fsm)
1733{
1734	const struct stfsm_seq *seq = &stfsm_seq_erase_chip;
1735
1736	dev_dbg(fsm->dev, "erasing chip\n");
1737
1738	stfsm_load_seq(fsm, seq);
1739
1740	stfsm_wait_seq(fsm);
1741
1742	return stfsm_wait_busy(fsm);
1743}
1744
1745/*
1746 * Write an address range to the flash chip.  Data must be written in
1747 * FLASH_PAGESIZE chunks.  The address range may be any size provided
1748 * it is within the physical boundaries.
1749 */
1750static int stfsm_mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
1751			   size_t *retlen, const u_char *buf)
1752{
1753	struct stfsm *fsm = dev_get_drvdata(mtd->dev.parent);
1754
1755	u32 page_offs;
1756	u32 bytes;
1757	uint8_t *b = (uint8_t *)buf;
1758	int ret = 0;
1759
1760	dev_dbg(fsm->dev, "%s to 0x%08x, len %zd\n", __func__, (u32)to, len);
1761
1762	/* Offset within page */
1763	page_offs = to % FLASH_PAGESIZE;
1764
1765	mutex_lock(&fsm->lock);
1766
1767	while (len) {
1768		/* Write up to page boundary */
1769		bytes = min_t(size_t, FLASH_PAGESIZE - page_offs, len);
1770
1771		ret = stfsm_write(fsm, b, bytes, to);
1772		if (ret)
1773			goto out1;
1774
1775		b += bytes;
1776		len -= bytes;
1777		to += bytes;
1778
1779		/* We are now page-aligned */
1780		page_offs = 0;
1781
1782		*retlen += bytes;
1783
1784	}
1785
1786out1:
1787	mutex_unlock(&fsm->lock);
1788
1789	return ret;
1790}
1791
1792/*
1793 * Erase an address range on the flash chip. The address range may extend
1794 * one or more erase sectors.  Return an error is there is a problem erasing.
1795 */
1796static int stfsm_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
1797{
1798	struct stfsm *fsm = dev_get_drvdata(mtd->dev.parent);
1799	u32 addr, len;
1800	int ret;
1801
1802	dev_dbg(fsm->dev, "%s at 0x%llx, len %lld\n", __func__,
1803		(long long)instr->addr, (long long)instr->len);
1804
1805	addr = instr->addr;
1806	len = instr->len;
1807
1808	mutex_lock(&fsm->lock);
1809
1810	/* Whole-chip erase? */
1811	if (len == mtd->size) {
1812		ret = stfsm_erase_chip(fsm);
1813		if (ret)
1814			goto out1;
1815	} else {
1816		while (len) {
1817			ret = stfsm_erase_sector(fsm, addr);
1818			if (ret)
1819				goto out1;
1820
1821			addr += mtd->erasesize;
1822			len -= mtd->erasesize;
1823		}
1824	}
1825
1826	mutex_unlock(&fsm->lock);
1827
1828	instr->state = MTD_ERASE_DONE;
1829	mtd_erase_callback(instr);
1830
1831	return 0;
1832
1833out1:
1834	instr->state = MTD_ERASE_FAILED;
1835	mutex_unlock(&fsm->lock);
1836
1837	return ret;
1838}
1839
1840static void stfsm_read_jedec(struct stfsm *fsm, uint8_t *jedec)
1841{
1842	const struct stfsm_seq *seq = &stfsm_seq_read_jedec;
1843	uint32_t tmp[2];
1844
1845	stfsm_load_seq(fsm, seq);
1846
1847	stfsm_read_fifo(fsm, tmp, 8);
1848
1849	memcpy(jedec, tmp, 5);
1850
1851	stfsm_wait_seq(fsm);
1852}
1853
1854static struct flash_info *stfsm_jedec_probe(struct stfsm *fsm)
1855{
1856	struct flash_info	*info;
1857	u16                     ext_jedec;
1858	u32			jedec;
1859	u8			id[5];
1860
1861	stfsm_read_jedec(fsm, id);
1862
1863	jedec     = id[0] << 16 | id[1] << 8 | id[2];
1864	/*
1865	 * JEDEC also defines an optional "extended device information"
1866	 * string for after vendor-specific data, after the three bytes
1867	 * we use here. Supporting some chips might require using it.
1868	 */
1869	ext_jedec = id[3] << 8  | id[4];
1870
1871	dev_dbg(fsm->dev, "JEDEC =  0x%08x [%02x %02x %02x %02x %02x]\n",
1872		jedec, id[0], id[1], id[2], id[3], id[4]);
1873
1874	for (info = flash_types; info->name; info++) {
1875		if (info->jedec_id == jedec) {
1876			if (info->ext_id && info->ext_id != ext_jedec)
1877				continue;
1878			return info;
1879		}
1880	}
1881	dev_err(fsm->dev, "Unrecognized JEDEC id %06x\n", jedec);
1882
1883	return NULL;
1884}
1885
1886static int stfsm_set_mode(struct stfsm *fsm, uint32_t mode)
1887{
1888	int ret, timeout = 10;
1889
1890	/* Wait for controller to accept mode change */
1891	while (--timeout) {
1892		ret = readl(fsm->base + SPI_STA_MODE_CHANGE);
1893		if (ret & 0x1)
1894			break;
1895		udelay(1);
1896	}
1897
1898	if (!timeout)
1899		return -EBUSY;
1900
1901	writel(mode, fsm->base + SPI_MODESELECT);
1902
1903	return 0;
1904}
1905
1906static void stfsm_set_freq(struct stfsm *fsm, uint32_t spi_freq)
1907{
1908	uint32_t emi_freq;
1909	uint32_t clk_div;
1910
1911	emi_freq = clk_get_rate(fsm->clk);
1912
1913	/*
1914	 * Calculate clk_div - values between 2 and 128
1915	 * Multiple of 2, rounded up
1916	 */
1917	clk_div = 2 * DIV_ROUND_UP(emi_freq, 2 * spi_freq);
1918	if (clk_div < 2)
1919		clk_div = 2;
1920	else if (clk_div > 128)
1921		clk_div = 128;
1922
1923	/*
1924	 * Determine a suitable delay for the IP to complete a change of
1925	 * direction of the FIFO. The required delay is related to the clock
1926	 * divider used. The following heuristics are based on empirical tests,
1927	 * using a 100MHz EMI clock.
1928	 */
1929	if (clk_div <= 4)
1930		fsm->fifo_dir_delay = 0;
1931	else if (clk_div <= 10)
1932		fsm->fifo_dir_delay = 1;
1933	else
1934		fsm->fifo_dir_delay = DIV_ROUND_UP(clk_div, 10);
1935
1936	dev_dbg(fsm->dev, "emi_clk = %uHZ, spi_freq = %uHZ, clk_div = %u\n",
1937		emi_freq, spi_freq, clk_div);
1938
1939	writel(clk_div, fsm->base + SPI_CLOCKDIV);
1940}
1941
1942static int stfsm_init(struct stfsm *fsm)
1943{
1944	int ret;
1945
1946	/* Perform a soft reset of the FSM controller */
1947	writel(SEQ_CFG_SWRESET, fsm->base + SPI_FAST_SEQ_CFG);
1948	udelay(1);
1949	writel(0, fsm->base + SPI_FAST_SEQ_CFG);
1950
1951	/* Set clock to 'safe' frequency initially */
1952	stfsm_set_freq(fsm, STFSM_FLASH_SAFE_FREQ);
1953
1954	/* Switch to FSM */
1955	ret = stfsm_set_mode(fsm, SPI_MODESELECT_FSM);
1956	if (ret)
1957		return ret;
1958
1959	/* Set timing parameters */
1960	writel(SPI_CFG_DEVICE_ST            |
1961	       SPI_CFG_DEFAULT_MIN_CS_HIGH  |
1962	       SPI_CFG_DEFAULT_CS_SETUPHOLD |
1963	       SPI_CFG_DEFAULT_DATA_HOLD,
1964	       fsm->base + SPI_CONFIGDATA);
1965	writel(STFSM_DEFAULT_WR_TIME, fsm->base + SPI_STATUS_WR_TIME_REG);
1966
1967	/*
1968	 * Set the FSM 'WAIT' delay to the minimum workable value.  Note, for
1969	 * our purposes, the WAIT instruction is used purely to achieve
1970	 * "sequence validity" rather than actually implement a delay.
1971	 */
1972	writel(0x00000001, fsm->base + SPI_PROGRAM_ERASE_TIME);
1973
1974	/* Clear FIFO, just in case */
1975	stfsm_clear_fifo(fsm);
1976
1977	return 0;
1978}
1979
1980static void stfsm_fetch_platform_configs(struct platform_device *pdev)
1981{
1982	struct stfsm *fsm = platform_get_drvdata(pdev);
1983	struct device_node *np = pdev->dev.of_node;
1984	struct regmap *regmap;
1985	uint32_t boot_device_reg;
1986	uint32_t boot_device_spi;
1987	uint32_t boot_device;     /* Value we read from *boot_device_reg */
1988	int ret;
1989
1990	/* Booting from SPI NOR Flash is the default */
1991	fsm->booted_from_spi = true;
1992
1993	regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
1994	if (IS_ERR(regmap))
1995		goto boot_device_fail;
1996
1997	fsm->reset_signal = of_property_read_bool(np, "st,reset-signal");
1998
1999	fsm->reset_por = of_property_read_bool(np, "st,reset-por");
2000
2001	/* Where in the syscon the boot device information lives */
2002	ret = of_property_read_u32(np, "st,boot-device-reg", &boot_device_reg);
2003	if (ret)
2004		goto boot_device_fail;
2005
2006	/* Boot device value when booted from SPI NOR */
2007	ret = of_property_read_u32(np, "st,boot-device-spi", &boot_device_spi);
2008	if (ret)
2009		goto boot_device_fail;
2010
2011	ret = regmap_read(regmap, boot_device_reg, &boot_device);
2012	if (ret)
2013		goto boot_device_fail;
2014
2015	if (boot_device != boot_device_spi)
2016		fsm->booted_from_spi = false;
2017
2018	return;
2019
2020boot_device_fail:
2021	dev_warn(&pdev->dev,
2022		 "failed to fetch boot device, assuming boot from SPI\n");
2023}
2024
2025static int stfsm_probe(struct platform_device *pdev)
2026{
2027	struct device_node *np = pdev->dev.of_node;
2028	struct mtd_part_parser_data ppdata;
2029	struct flash_info *info;
2030	struct resource *res;
2031	struct stfsm *fsm;
2032	int ret;
2033
2034	if (!np) {
2035		dev_err(&pdev->dev, "No DT found\n");
2036		return -EINVAL;
2037	}
2038	ppdata.of_node = np;
2039
2040	fsm = devm_kzalloc(&pdev->dev, sizeof(*fsm), GFP_KERNEL);
2041	if (!fsm)
2042		return -ENOMEM;
2043
2044	fsm->dev = &pdev->dev;
2045
2046	platform_set_drvdata(pdev, fsm);
2047
2048	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2049	if (!res) {
2050		dev_err(&pdev->dev, "Resource not found\n");
2051		return -ENODEV;
2052	}
2053
2054	fsm->base = devm_ioremap_resource(&pdev->dev, res);
2055	if (IS_ERR(fsm->base)) {
2056		dev_err(&pdev->dev,
2057			"Failed to reserve memory region %pR\n", res);
2058		return PTR_ERR(fsm->base);
2059	}
2060
2061	fsm->clk = devm_clk_get(&pdev->dev, NULL);
2062	if (IS_ERR(fsm->clk)) {
2063		dev_err(fsm->dev, "Couldn't find EMI clock.\n");
2064		return PTR_ERR(fsm->clk);
2065	}
2066
2067	ret = clk_prepare_enable(fsm->clk);
2068	if (ret) {
2069		dev_err(fsm->dev, "Failed to enable EMI clock.\n");
2070		return ret;
2071	}
2072
2073	mutex_init(&fsm->lock);
2074
2075	ret = stfsm_init(fsm);
2076	if (ret) {
2077		dev_err(&pdev->dev, "Failed to initialise FSM Controller\n");
2078		return ret;
2079	}
2080
2081	stfsm_fetch_platform_configs(pdev);
2082
2083	/* Detect SPI FLASH device */
2084	info = stfsm_jedec_probe(fsm);
2085	if (!info)
2086		return -ENODEV;
2087	fsm->info = info;
2088
2089	/* Use device size to determine address width */
2090	if (info->sector_size * info->n_sectors > 0x1000000)
2091		info->flags |= FLASH_FLAG_32BIT_ADDR;
2092
2093	/*
2094	 * Configure READ/WRITE/ERASE sequences according to platform and
2095	 * device flags.
2096	 */
2097	if (info->config) {
2098		ret = info->config(fsm);
2099		if (ret)
2100			return ret;
2101	} else {
2102		ret = stfsm_prepare_rwe_seqs_default(fsm);
2103		if (ret)
2104			return ret;
2105	}
2106
2107	fsm->mtd.name		= info->name;
2108	fsm->mtd.dev.parent	= &pdev->dev;
2109	fsm->mtd.type		= MTD_NORFLASH;
2110	fsm->mtd.writesize	= 4;
2111	fsm->mtd.writebufsize	= fsm->mtd.writesize;
2112	fsm->mtd.flags		= MTD_CAP_NORFLASH;
2113	fsm->mtd.size		= info->sector_size * info->n_sectors;
2114	fsm->mtd.erasesize	= info->sector_size;
2115
2116	fsm->mtd._read  = stfsm_mtd_read;
2117	fsm->mtd._write = stfsm_mtd_write;
2118	fsm->mtd._erase = stfsm_mtd_erase;
2119
2120	dev_info(&pdev->dev,
2121		"Found serial flash device: %s\n"
2122		" size = %llx (%lldMiB) erasesize = 0x%08x (%uKiB)\n",
2123		info->name,
2124		(long long)fsm->mtd.size, (long long)(fsm->mtd.size >> 20),
2125		fsm->mtd.erasesize, (fsm->mtd.erasesize >> 10));
2126
2127	return mtd_device_parse_register(&fsm->mtd, NULL, &ppdata, NULL, 0);
2128}
2129
2130static int stfsm_remove(struct platform_device *pdev)
2131{
2132	struct stfsm *fsm = platform_get_drvdata(pdev);
2133
2134	return mtd_device_unregister(&fsm->mtd);
2135}
2136
2137#ifdef CONFIG_PM_SLEEP
2138static int stfsmfsm_suspend(struct device *dev)
2139{
2140	struct stfsm *fsm = dev_get_drvdata(dev);
2141
2142	clk_disable_unprepare(fsm->clk);
2143
2144	return 0;
2145}
2146
2147static int stfsmfsm_resume(struct device *dev)
2148{
2149	struct stfsm *fsm = dev_get_drvdata(dev);
2150
2151	clk_prepare_enable(fsm->clk);
2152
2153	return 0;
2154}
2155#endif
2156
2157static SIMPLE_DEV_PM_OPS(stfsm_pm_ops, stfsmfsm_suspend, stfsmfsm_resume);
2158
2159static const struct of_device_id stfsm_match[] = {
2160	{ .compatible = "st,spi-fsm", },
2161	{},
2162};
2163MODULE_DEVICE_TABLE(of, stfsm_match);
2164
2165static struct platform_driver stfsm_driver = {
2166	.probe		= stfsm_probe,
2167	.remove		= stfsm_remove,
2168	.driver		= {
2169		.name	= "st-spi-fsm",
2170		.of_match_table = stfsm_match,
2171		.pm     = &stfsm_pm_ops,
2172	},
2173};
2174module_platform_driver(stfsm_driver);
2175
2176MODULE_AUTHOR("Angus Clark <angus.clark@st.com>");
2177MODULE_DESCRIPTION("ST SPI FSM driver");
2178MODULE_LICENSE("GPL");
2179