[PATCH linux-next 2/4] mtd: spi-nor: properly detect the memory when it boots in Quad or Dual mode
From: Cyrille Pitchen
Date: Fri Sep 18 2015 - 11:50:10 EST
The quad (or dual) mode of a spi-nor memory may be enabled at boot time by
non-volatile bits in some setting register. Also such a mode may have
already been enabled at early stage by some boot loader.
Hence, we should not guess the spi-nor memory is always configured for the
regular SPI 1-1-1 protocol.
Micron and Macronix memories, once their Quad (or dual for Micron) mode
enabled, no longer process the regular JEDEC Read ID (0x9f) command but
instead reply to a new command: JEDEC Read ID Multiple I/O (0xaf).
Besides, in Quad mode both memory manufacturers expect ALL commands to
use the SPI 4-4-4 protocol. For Micron memories, enabling their Dual mode
implies to use the SPI 2-2-2 protocol for ALL commands.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxx>
---
drivers/mtd/spi-nor/spi-nor.c | 52 +++++++++++++++++++++++++++++++++++++++----
include/linux/mtd/spi-nor.h | 23 +++++++++++++++++--
2 files changed, 69 insertions(+), 6 deletions(-)
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 8818d4325d20..b857e9be2026 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -61,6 +61,11 @@ struct flash_info {
#define JEDEC_MFR(info) ((info)->id[0])
+struct read_id_config {
+ enum read_mode mode;
+ enum spi_protocol proto;
+};
+
static const struct flash_info *spi_nor_match_id(const char *name);
/*
@@ -701,11 +706,16 @@ static const struct flash_info spi_nor_ids[] = {
{ },
};
-static const struct flash_info *spi_nor_read_id(struct spi_nor *nor)
+static const struct flash_info *spi_nor_read_id(struct spi_nor *nor,
+ enum read_mode mode)
{
- int tmp;
+ int i, tmp;
u8 id[SPI_NOR_MAX_ID_LEN];
const struct flash_info *info;
+ static const struct read_id_config configs[] = {
+ {SPI_NOR_QUAD, SPI_PROTO_4_4_4},
+ {SPI_NOR_DUAL, SPI_PROTO_2_2_2}
+ };
tmp = nor->read_reg(nor, SPINOR_OP_RDID, id, SPI_NOR_MAX_ID_LEN);
if (tmp < 0) {
@@ -713,6 +723,34 @@ static const struct flash_info *spi_nor_read_id(struct spi_nor *nor)
return ERR_PTR(tmp);
}
+ /* Special case for Micron/Macronix qspi nor. */
+ if ((id[0] == 0xff && id[1] == 0xff && id[2] == 0xff) ||
+ (id[0] == 0x00 && id[1] == 0x00 && id[2] == 0x00))
+ for (i = 0; i < ARRAY_SIZE(configs); ++i) {
+ if (configs[i].mode != mode)
+ continue;
+
+ /* Set this protocol for all commands. */
+ nor->reg_proto = configs[i].proto;
+ nor->read_proto = configs[i].proto;
+ nor->write_proto = configs[i].proto;
+ nor->erase_proto = configs[i].proto;
+
+ /*
+ * Multiple I/O Read ID only returns the Manufacturer ID
+ * (1 byte) and the Device ID (2 bytes). So we reset the
+ * remaining bytes.
+ */
+ memset(id, 0, sizeof(id));
+ tmp = nor->read_reg(nor, SPINOR_OP_MIO_RDID, id, 3);
+ if (tmp < 0) {
+ dev_dbg(nor->dev,
+ "error %d reading JEDEC ID Multi I/O\n",
+ tmp);
+ return ERR_PTR(tmp);
+ }
+ }
+
for (tmp = 0; tmp < ARRAY_SIZE(spi_nor_ids) - 1; tmp++) {
info = &spi_nor_ids[tmp];
if (info->id_len) {
@@ -1012,11 +1050,17 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
if (ret)
return ret;
+ /* Reset SPI protocol for all commands */
+ nor->erase_proto = SPI_PROTO_1_1_1;
+ nor->read_proto = SPI_PROTO_1_1_1;
+ nor->write_proto = SPI_PROTO_1_1_1;
+ nor->reg_proto = SPI_PROTO_1_1_1;
+
if (name)
info = spi_nor_match_id(name);
/* Try to auto-detect if chip name wasn't specified or not found */
if (!info)
- info = spi_nor_read_id(nor);
+ info = spi_nor_read_id(nor, mode);
if (IS_ERR_OR_NULL(info))
return -ENOENT;
@@ -1027,7 +1071,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
if (name && info->id_len) {
const struct flash_info *jinfo;
- jinfo = spi_nor_read_id(nor);
+ jinfo = spi_nor_read_id(nor, mode);
if (IS_ERR(jinfo)) {
return PTR_ERR(jinfo);
} else if (jinfo != info) {
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 672595a381c5..97e52ee475e9 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -57,8 +57,9 @@
#define SPINOR_OP_BRWR 0x17 /* Bank register write */
/* Used for Micron flashes only. */
-#define SPINOR_OP_RD_EVCR 0x65 /* Read EVCR register */
-#define SPINOR_OP_WD_EVCR 0x61 /* Write EVCR register */
+#define SPINOR_OP_MIO_RDID 0xaf /* Multiple I/O Read JEDEC ID */
+#define SPINOR_OP_RD_EVCR 0x65 /* Read EVCR register */
+#define SPINOR_OP_WD_EVCR 0x61 /* Write EVCR register */
/* Status Register bits. */
#define SR_WIP 1 /* Write in progress */
@@ -87,6 +88,16 @@ enum read_mode {
SPI_NOR_QUAD,
};
+enum spi_protocol {
+ SPI_PROTO_1_1_1, /* SPI */
+ SPI_PROTO_1_1_2, /* Dual Output */
+ SPI_PROTO_1_1_4, /* Quad Output */
+ SPI_PROTO_1_2_2, /* Dual IO */
+ SPI_PROTO_1_4_4, /* Quad IO */
+ SPI_PROTO_2_2_2, /* Dual Command */
+ SPI_PROTO_4_4_4, /* Quad Command */
+};
+
#define SPI_NOR_MAX_CMD_SIZE 8
enum spi_nor_ops {
SPI_NOR_OPS_READ = 0,
@@ -117,6 +128,10 @@ struct mtd_info;
* @flash_read: the mode of the read
* @sst_write_second: used by the SST write operation
* @flags: flag options for the current SPI-NOR (SNOR_F_*)
+ * @erase_proto: the SPI protocol used by erase operations
+ * @read_proto: the SPI protocol used by read operations
+ * @write_proto: the SPI protocol used by write operations
+ * @reg_proto the SPI protocol used by read_reg/write_reg operations
* @cmd_buf: used by the write_reg
* @prepare: [OPTIONAL] do some preparations for the
* read/write/erase/lock/unlock operations
@@ -143,6 +158,10 @@ struct spi_nor {
u8 read_opcode;
u8 read_dummy;
u8 program_opcode;
+ enum spi_protocol erase_proto;
+ enum spi_protocol read_proto;
+ enum spi_protocol write_proto;
+ enum spi_protocol reg_proto;
enum read_mode flash_read;
bool sst_write_second;
u32 flags;
--
1.8.2.2
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