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.

Signed-off-by: Lee Jones <lee.jo...@linaro.org>
---
 drivers/mtd/devices/st_spi_fsm.c | 53 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
index 5582df0..3b56b6e 100644
--- a/drivers/mtd/devices/st_spi_fsm.c
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -236,6 +236,15 @@
 #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;
@@ -244,6 +253,7 @@ struct stfsm {
        struct mutex            lock;
        struct flash_info       *info;
 
+       uint32_t                configuration;
        uint32_t                fifo_dir_delay;
        bool                    booted_from_spi;
        bool                    reset_signal;
@@ -438,6 +448,49 @@ 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 = {
-- 
1.8.3.2

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