[PATCH v3 07/13] mtd: st_spi_fsm: Add support for N25Q512 and N25Q00A devices

Lee Jones
2014-12-15T11:59:14Z

From: Angus Clark <angus.clark@st.com>

This patch adds support for the Micron N25Q512 and N25Q00A Serial Flash devices.
Unlike previous Micron devices, it is now mandatory to check the Flags Status
Register following a Write or Erase operation. The N25Q512A device presents a
further complication in that different variants of the device use different
opcodes for the WRITE_1_4_4 operation. Since there is no easy way to determine
at runtime which variant is being used, FLASH_CAPS_WRITE_1_4_4 support is
removed for N25Q512 devices, resulting in WRITE_1_1_4 being used instead.

The following devices have been tested:

b2000C + N25Q512A13GSF40G
b2000C + N25Q00AA13GSF40G
b2147A + N25Q512A83GSF40X

Signed-off-by: Angus Clark <angus.clark@st.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
drivers/mtd/devices/st_spi_fsm.c | 96 +++++++++++++++++++++++++++++++++++++---
1 file changed, 91 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
index 7e6cd26..4fac169 100644
--- a/drivers/mtd/devices/st_spi_fsm.c
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -240,12 +240,25 @@
#define S25FL_STATUS_E_ERR 0x20
#define S25FL_STATUS_P_ERR 0x40

+/* N25Q - READ/WRITE/CLEAR NON/VOLATILE STATUS/CONFIG Registers */
+#define N25Q_CMD_RFSR 0x70
+#define N25Q_CMD_CLFSR 0x50
#define N25Q_CMD_WRVCR 0x81
#define N25Q_CMD_RDVCR 0x85
#define N25Q_CMD_RDVECR 0x65
#define N25Q_CMD_RDNVCR 0xb5
#define N25Q_CMD_WRNVCR 0xb1

+/* N25Q Flags Status Register: Error Flags */
+#define N25Q_FLAGS_ERR_ERASE BIT(5)
+#define N25Q_FLAGS_ERR_PROG BIT(4)
+#define N25Q_FLAGS_ERR_VPP BIT(3)
+#define N25Q_FLAGS_ERR_PROT BIT(1)
+#define N25Q_FLAGS_ERROR (N25Q_FLAGS_ERR_ERASE | \
+ N25Q_FLAGS_ERR_PROG | \
+ N25Q_FLAGS_ERR_VPP | \
+ N25Q_FLAGS_ERR_PROT)
+
#define FLASH_PAGESIZE 256 /* In Bytes */
#define FLASH_PAGESIZE_32 (FLASH_PAGESIZE / 4) /* In uint32_t */
#define FLASH_MAX_BUSY_WAIT (300 * HZ) /* Maximum 'CHIPERASE' time */
@@ -257,6 +270,7 @@
#define CFG_WRITE_TOGGLE_32BIT_ADDR 0x00000002
#define CFG_ERASESEC_TOGGLE_32BIT_ADDR 0x00000008
#define CFG_S25FL_CHECK_ERROR_FLAGS 0x00000010
+#define CFG_N25Q_CHECK_ERROR_FLAGS 0x00000020

struct stfsm_seq {
uint32_t data_size;
@@ -399,6 +413,7 @@ static struct flash_info flash_types[] = {
(MX25_FLAG | FLASH_FLAG_32BIT_ADDR | FLASH_FLAG_RESET), 70,
stfsm_mx25_config},

+ /* Micron N25Qxxx */
#define N25Q_FLAG (FLASH_FLAG_READ_WRITE | \
FLASH_FLAG_READ_FAST | \
FLASH_FLAG_READ_1_1_2 | \
@@ -411,10 +426,29 @@ static struct flash_info flash_types[] = {
FLASH_FLAG_WRITE_1_4_4)
{ "n25q128", 0x20ba18, 0, 64 * 1024, 256, N25Q_FLAG, 108,
stfsm_n25q_config },
- { "n25q256", 0x20ba19, 0, 64 * 1024, 512,
- N25Q_FLAG | FLASH_FLAG_32BIT_ADDR, 108, stfsm_n25q_config },
- { "n25q512", 0x20ba20, 0, 64 * 1024, 1024,
- N25Q_FLAG | FLASH_FLAG_32BIT_ADDR, 108, stfsm_n25q_config},
+
+ /* Micron N25Q256/N25Q512/N25Q00A (32-bit ADDR devices)
+ *
+ * Versions are available with or without a dedicated RESET# pin
+ * (e.g. N25Q512A83GSF40G vs. N25Q512A13GSF40G). To complicate matters,
+ * the versions that include a RESET# pin (Feature Set = 8) require a
+ * different opcode for the FLASH_CMD_WRITE_1_4_4 command.
+ * Unfortunately it is not possible to determine easily at run-time
+ * which version is being used. We therefore remove support for
+ * FLASH_FLAG_WRITE_1_4_4 (falling back to FLASH_FLAG_WRITE_1_1_4), and
+ * defer overall support for RESET# to the board-level platform/Device
+ * Tree property "reset-signal".
+ */
+#define N25Q_32BIT_ADDR_FLAG ((N25Q_FLAG | \
+ FLASH_FLAG_32BIT_ADDR | \
+ FLASH_FLAG_RESET) & \
+ ~FLASH_FLAG_WRITE_1_4_4)
+ { "n25q256", 0x20ba19, 0, 64 * 1024, 512,
+ N25Q_32BIT_ADDR_FLAG, 108, stfsm_n25q_config},
+ { "n25q512", 0x20ba20, 0x1000, 64 * 1024, 1024,
+ N25Q_32BIT_ADDR_FLAG, 108, stfsm_n25q_config},
+ { "n25q00a", 0x20ba21, 0x1000, 64 * 1024, 2048,
+ N25Q_32BIT_ADDR_FLAG, 108, stfsm_n25q_config},

/*
* Spansion S25FLxxxP
@@ -892,6 +926,30 @@ static int stfsm_write_fifo(struct stfsm *fsm, const uint32_t *buf,
return size;
}

+static int n25q_clear_flags(struct stfsm *fsm)
+{
+ struct stfsm_seq seq = {
+ .seq_opc[0] = (SEQ_OPC_PADS_1 |
+ SEQ_OPC_CYCLES(8) |
+ SEQ_OPC_OPCODE(N25Q_CMD_CLFSR) |
+ SEQ_OPC_CSDEASSERT),
+ .seq = {
+ STFSM_INST_CMD1,
+ STFSM_INST_STOP,
+ },
+ .seq_cfg = (SEQ_CFG_PADS_1 |
+ SEQ_CFG_READNOTWRITE |
+ SEQ_CFG_CSDEASSERT |
+ SEQ_CFG_STARTSEQ),
+ };
+
+ stfsm_load_seq(fsm, &seq);
+
+ stfsm_wait_seq(fsm);
+
+ return 0;
+}
+
static int stfsm_enter_32bit_addr(struct stfsm *fsm, int enter)
{
struct stfsm_seq *seq = &fsm->stfsm_seq_en_32bit_addr;
@@ -1252,10 +1310,18 @@ static int stfsm_mx25_config(struct stfsm *fsm)
static int stfsm_n25q_config(struct stfsm *fsm)
{
uint32_t flags = fsm->info->flags;
- uint8_t vcr;
+ uint8_t vcr, sta;
int ret = 0;
bool soc_reset;

+ /*
+ * Check/Clear Error Flags
+ */
+ fsm->configuration |= CFG_N25Q_CHECK_ERROR_FLAGS;
+ stfsm_read_status(fsm, N25Q_CMD_RFSR, &sta, 1);
+ if (sta & N25Q_FLAGS_ERROR)
+ n25q_clear_flags(fsm);
+
/* Configure 'READ' sequence */
if (flags & FLASH_FLAG_32BIT_ADDR)
ret = stfsm_search_prepare_rw_seq(fsm, &fsm->stfsm_seq_read,
@@ -1631,6 +1697,7 @@ static int stfsm_write(struct stfsm *fsm, const uint8_t *buf,
uint32_t page_buf[FLASH_PAGESIZE_32];
uint8_t *t = (uint8_t *)&tmp;
const uint8_t *p;
+ uint8_t sta;
int ret;

dev_dbg(fsm->dev, "writing %d bytes to 0x%08x\n", size, offset);
@@ -1701,6 +1768,15 @@ static int stfsm_write(struct stfsm *fsm, const uint8_t *buf,
if (ret && fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS)
stfsm_s25fl_clear_status_reg(fsm);

+ /* N25Q: Check/Clear Error Flags */
+ if (fsm->configuration & CFG_N25Q_CHECK_ERROR_FLAGS) {
+ stfsm_read_status(fsm, N25Q_CMD_RFSR, &sta, 1);
+ if (sta & N25Q_FLAGS_ERROR) {
+ n25q_clear_flags(fsm);
+ ret = -EPROTO;
+ }
+ }
+
/* Exit 32-bit address mode, if required */
if (fsm->configuration & CFG_WRITE_TOGGLE_32BIT_ADDR)
stfsm_enter_32bit_addr(fsm, 0);
@@ -1743,6 +1819,7 @@ static int stfsm_mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
static int stfsm_erase_sector(struct stfsm *fsm, uint32_t offset)
{
struct stfsm_seq *seq = &stfsm_seq_erase_sector;
+ uint8_t sta;
int ret;

dev_dbg(fsm->dev, "erasing sector at 0x%08x\n", offset);
@@ -1763,6 +1840,15 @@ static int stfsm_erase_sector(struct stfsm *fsm, uint32_t offset)
if (ret && fsm->configuration & CFG_S25FL_CHECK_ERROR_FLAGS)
stfsm_s25fl_clear_status_reg(fsm);

+ /* N25Q: Check/Clear Error Flags */
+ if (fsm->configuration & CFG_N25Q_CHECK_ERROR_FLAGS) {
+ stfsm_read_status(fsm, N25Q_CMD_RFSR, &sta, 1);
+ if (sta & N25Q_FLAGS_ERROR) {
+ n25q_clear_flags(fsm);
+ ret = -EPROTO;
+ }
+ }
+
/* Exit 32-bit address mode, if required */
if (fsm->configuration & CFG_ERASESEC_TOGGLE_32BIT_ADDR)
stfsm_enter_32bit_addr(fsm, 0);
--
1.9.1