mtd: st_spi_fsm: Supply the N25Qxxx specific read configurations

The N25Qxxx Serial Flash devices required different sequence
configurations depending on whether they're running in 24bit (3Byte)
or 32bit (4Byte) mode. We provide those here.

Acked-by Angus Clark <angus.clark@st.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

drivers/mtd/devices/st_spi_fsm.c

@@ -200,6 +200,53 @@
 
 #define STFSM_MAX_WAIT_SEQ_MS  1000     /* FSM execution time */
 
+/* Flash Commands */
+#define FLASH_CMD_WREN         0x06
+#define FLASH_CMD_WRDI         0x04
+#define FLASH_CMD_RDID         0x9f
+#define FLASH_CMD_RDSR         0x05
+#define FLASH_CMD_RDSR2                0x35
+#define FLASH_CMD_WRSR         0x01
+#define FLASH_CMD_SE_4K                0x20
+#define FLASH_CMD_SE_32K       0x52
+#define FLASH_CMD_SE           0xd8
+#define FLASH_CMD_CHIPERASE    0xc7
+#define FLASH_CMD_WRVCR                0x81
+#define FLASH_CMD_RDVCR                0x85
+
+#define FLASH_CMD_READ         0x03    /* READ */
+#define FLASH_CMD_READ_FAST    0x0b    /* FAST READ */
+#define FLASH_CMD_READ_1_1_2   0x3b    /* DUAL OUTPUT READ */
+#define FLASH_CMD_READ_1_2_2   0xbb    /* DUAL I/O READ */
+#define FLASH_CMD_READ_1_1_4   0x6b    /* QUAD OUTPUT READ */
+#define FLASH_CMD_READ_1_4_4   0xeb    /* QUAD I/O READ */
+
+#define FLASH_CMD_WRITE                0x02    /* PAGE PROGRAM */
+#define FLASH_CMD_WRITE_1_1_2  0xa2    /* DUAL INPUT PROGRAM */
+#define FLASH_CMD_WRITE_1_2_2  0xd2    /* DUAL INPUT EXT PROGRAM */
+#define FLASH_CMD_WRITE_1_1_4  0x32    /* QUAD INPUT PROGRAM */
+#define FLASH_CMD_WRITE_1_4_4  0x12    /* QUAD INPUT EXT PROGRAM */
+
+#define FLASH_CMD_EN4B_ADDR    0xb7    /* Enter 4-byte address mode */
+#define FLASH_CMD_EX4B_ADDR    0xe9    /* Exit 4-byte address mode */
+
+/* READ commands with 32-bit addressing (N25Q256 and S25FLxxxS) */
+#define FLASH_CMD_READ4                0x13
+#define FLASH_CMD_READ4_FAST   0x0c
+#define FLASH_CMD_READ4_1_1_2  0x3c
+#define FLASH_CMD_READ4_1_2_2  0xbc
+#define FLASH_CMD_READ4_1_1_4  0x6c
+#define FLASH_CMD_READ4_1_4_4  0xec
+
+/*
+ * Flags to tweak operation of default read/write/erase routines
+ */
+#define CFG_READ_TOGGLE_32BIT_ADDR     0x00000001
+#define CFG_WRITE_TOGGLE_32BIT_ADDR    0x00000002
+#define CFG_WRITE_EX_32BIT_ADDR_DELAY  0x00000004
+#define CFG_ERASESEC_TOGGLE_32BIT_ADDR 0x00000008
+#define CFG_S25FL_CHECK_ERROR_FLAGS    0x00000010
+
 struct stfsm {
 	struct device		*dev;
 	void __iomem		*base;
@@ -208,6 +255,7 @@ struct stfsm {
 	struct mutex		lock;
 	struct flash_info       *info;
 
+	uint32_t                configuration;
 	uint32_t                fifo_dir_delay;
 	bool                    booted_from_spi;
 	bool                    reset_signal;
@@ -402,6 +450,49 @@ static struct seq_rw_config default_write_configs[] = {
 	{0x00,			 0,			0, 0, 0, 0x00, 0, 0},
 };
 
+/*
+ * [N25Qxxx] Configuration
+ */
+#define N25Q_VCR_DUMMY_CYCLES(x)	(((x) & 0xf) << 4)
+#define N25Q_VCR_XIP_DISABLED		((uint8_t)0x1 << 3)
+#define N25Q_VCR_WRAP_CONT		0x3
+
+/* N25Q 3-byte Address READ configurations
+ *	- 'FAST' variants configured for 8 dummy cycles.
+ *
+ * Note, the number of dummy cycles used for 'FAST' READ operations is
+ * configurable and would normally be tuned according to the READ command and
+ * operating frequency.  However, this applies universally to all 'FAST' READ
+ * commands, including those used by the SPIBoot controller, and remains in
+ * force until the device is power-cycled.  Since the SPIBoot controller is
+ * hard-wired to use 8 dummy cycles, we must configure the device to also use 8
+ * cycles.
+ */
+static struct seq_rw_config n25q_read3_configs[] = {
+	{FLASH_FLAG_READ_1_4_4, FLASH_CMD_READ_1_4_4,	0, 4, 4, 0x00, 0, 8},
+	{FLASH_FLAG_READ_1_1_4, FLASH_CMD_READ_1_1_4,	0, 1, 4, 0x00, 0, 8},
+	{FLASH_FLAG_READ_1_2_2, FLASH_CMD_READ_1_2_2,	0, 2, 2, 0x00, 0, 8},
+	{FLASH_FLAG_READ_1_1_2, FLASH_CMD_READ_1_1_2,	0, 1, 2, 0x00, 0, 8},
+	{FLASH_FLAG_READ_FAST,	FLASH_CMD_READ_FAST,	0, 1, 1, 0x00, 0, 8},
+	{FLASH_FLAG_READ_WRITE, FLASH_CMD_READ,	        0, 1, 1, 0x00, 0, 0},
+	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
+};
+
+/* N25Q 4-byte Address READ configurations
+ *	- use special 4-byte address READ commands (reduces overheads, and
+ *        reduces risk of hitting watchdog reset issues).
+ *	- 'FAST' variants configured for 8 dummy cycles (see note above.)
+ */
+static struct seq_rw_config n25q_read4_configs[] = {
+	{FLASH_FLAG_READ_1_4_4, FLASH_CMD_READ4_1_4_4,	0, 4, 4, 0x00, 0, 8},
+	{FLASH_FLAG_READ_1_1_4, FLASH_CMD_READ4_1_1_4,	0, 1, 4, 0x00, 0, 8},
+	{FLASH_FLAG_READ_1_2_2, FLASH_CMD_READ4_1_2_2,	0, 2, 2, 0x00, 0, 8},
+	{FLASH_FLAG_READ_1_1_2, FLASH_CMD_READ4_1_1_2,	0, 1, 2, 0x00, 0, 8},
+	{FLASH_FLAG_READ_FAST,	FLASH_CMD_READ4_FAST,	0, 1, 1, 0x00, 0, 8},
+	{FLASH_FLAG_READ_WRITE, FLASH_CMD_READ4,	0, 1, 1, 0x00, 0, 0},
+	{0x00,			0,			0, 0, 0, 0x00, 0, 0},
+};
+
 static struct stfsm_seq stfsm_seq_en_32bit_addr;/* Dynamically populated */
 
 static struct stfsm_seq stfsm_seq_read_jedec = {