Take as reference Linux kernel code:
drivers/mtd/devices/mtd_dataflash.c
commit 1da8869a428317a6d3cd8d47184cf87feb34a98b
Author: Andrey Smirnov <andrew.smir...@gmail.com>
Signed-off-by: Luca Ellero <luca.ell...@brickedbrain.com>
---
Changes for v2:
- add reference to Linux kernel commit
drivers/mtd/spi/sf_dataflash.c | 98 ++++++++++++++++++++++------------
1 file changed, 64 insertions(+), 34 deletions(-)
diff --git a/drivers/mtd/spi/sf_dataflash.c b/drivers/mtd/spi/sf_dataflash.c
index b59edd152c..351c41039a 100644
--- a/drivers/mtd/spi/sf_dataflash.c
+++ b/drivers/mtd/spi/sf_dataflash.c
@@ -70,6 +70,9 @@
#define OP_WRITE_SECURITY_REVC 0x9A
#define OP_WRITE_SECURITY 0x9B /* revision D */
+#define DATAFLASH_SHIFT_EXTID 24
+#define DATAFLASH_SHIFT_ID 40
+
struct dataflash {
uint8_t command[16];
unsigned short page_offset; /* offset in flash address */
@@ -455,7 +458,7 @@ struct data_flash_info {
* JEDEC id has a high byte of zero plus three data bytes:
* the manufacturer id, then a two byte device id.
*/
- uint32_t jedec_id;
+ uint64_t jedec_id;
/* The size listed here is what works with OP_ERASE_PAGE. */
unsigned nr_pages;
@@ -463,6 +466,7 @@ struct data_flash_info {
uint16_t pageoffset;
uint16_t flags;
+#define SUP_EXTID 0x0004 /* supports extended ID data */
#define SUP_POW2PS 0x0002 /* supports 2^N byte pages */
#define IS_POW2PS 0x0001 /* uses 2^N byte pages */
};
@@ -508,48 +512,26 @@ static struct data_flash_info dataflash_data[] = {
{ "at45db642d", 0x1f2800, 8192, 1024, 10, SUP_POW2PS | IS_POW2PS},
};
-static struct data_flash_info *jedec_probe(struct spi_slave *spi)
+static struct data_flash_info *jedec_lookup(struct spi_slave *spi,
+ u64 jedec, bool use_extid)
+
{
- int tmp;
- uint8_t id[5];
- uint32_t jedec;
- struct data_flash_info *info;
- u8 opcode = CMD_READ_ID;
+ struct data_flash_info *info;
int status;
- /*
- * JEDEC also defines an optional "extended device information"
- * string for after vendor-specific data, after the three bytes
- * we use here. Supporting some chips might require using it.
- *
- * If the vendor ID isn't Atmel's (0x1f), assume this call failed.
- * That's not an error; only rev C and newer chips handle it, and
- * only Atmel sells these chips.
- */
- tmp = spi_write_then_read(spi, &opcode, 1, NULL, id, sizeof(id));
- if (tmp < 0) {
- printf("dataflash: error %d reading JEDEC ID\n", tmp);
- return ERR_PTR(tmp);
- }
- if (id[0] != 0x1f)
- return NULL;
-
- jedec = id[0];
- jedec = jedec << 8;
- jedec |= id[1];
- jedec = jedec << 8;
- jedec |= id[2];
+ for (info = dataflash_data;
+ info < dataflash_data + ARRAY_SIZE(dataflash_data);
+ info++) {
+ if (use_extid && !(info->flags & SUP_EXTID))
+ continue;
- for (tmp = 0, info = dataflash_data;
- tmp < ARRAY_SIZE(dataflash_data);
- tmp++, info++) {
if (info->jedec_id == jedec) {
if (info->flags & SUP_POW2PS) {
status = dataflash_status(spi);
if (status < 0) {
debug("dataflash: status error %d\n",
status);
- return NULL;
+ return ERR_PTR(status);
}
if (status & 0x1) {
if (info->flags & IS_POW2PS)
@@ -564,12 +546,58 @@ static struct data_flash_info *jedec_probe(struct
spi_slave *spi)
}
}
+ return ERR_PTR(-ENODEV);
+}
+
+static struct data_flash_info *jedec_probe(struct spi_slave *spi)
+{
+ int tmp;
+ uint64_t jedec;
+ uint8_t id[sizeof(jedec)] = {0};
+ const unsigned int id_size = 5;
+ struct data_flash_info *info;
+ u8 opcode = CMD_READ_ID;
+
+ /*
+ * JEDEC also defines an optional "extended device information"
+ * string for after vendor-specific data, after the three bytes
+ * we use here. Supporting some chips might require using it.
+ *
+ * If the vendor ID isn't Atmel's (0x1f), assume this call failed.
+ * That's not an error; only rev C and newer chips handle it, and
+ * only Atmel sells these chips.
+ */
+ tmp = spi_write_then_read(spi, &opcode, 1, NULL, id, id_size);
+ if (tmp < 0) {
+ printf("dataflash: error %d reading JEDEC ID\n", tmp);
+ return ERR_PTR(tmp);
+ }
+
+ if (id[0] != 0x1f)
+ return NULL;
+
+ jedec = be64_to_cpup((__be64 *)id);
+
+ /*
+ * First, try to match device using extended device
+ * information
+ */
+ info = jedec_lookup(spi, jedec >> DATAFLASH_SHIFT_EXTID, true);
+ if (!IS_ERR(info))
+ return info;
+ /*
+ * If that fails, make another pass using regular ID
+ * information
+ */
+ info = jedec_lookup(spi, jedec >> DATAFLASH_SHIFT_ID, false);
+ if (!IS_ERR(info))
+ return info;
/*
* Treat other chips as errors ... we won't know the right page
* size (it might be binary) even when we can tell which density
* class is involved (legacy chip id scheme).
*/
- printf("dataflash: JEDEC id %06x not handled\n", jedec);
+ printf("dataflash: JEDEC id 0x%016llx not handled\n", jedec);
return ERR_PTR(-ENODEV);
}
@@ -618,6 +646,8 @@ static int spi_dataflash_probe(struct udevice *dev)
(info->flags & SUP_POW2PS) ? 'd' : 'c');
if (status < 0)
goto err_status;
+ else
+ return status;
}
/*
--
2.17.1
