Parse SCCR 22nd dword and check DTR Octal Mode Enable
Volatile bit for Octal DTR enable
Signed-off-by: JaimeLiao <jaimeliao...@gmail.com>
---
drivers/mtd/spi/spi-nor-core.c | 52 ++++++++++++++++++++++++++++++++++
include/linux/mtd/spi-nor.h | 1 +
2 files changed, 53 insertions(+)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index 2b6947cefc..14c33aea10 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -63,6 +63,10 @@ struct sfdp_parameter_header {
#define SFDP_SECTOR_MAP_ID 0xff81 /* Sector Map Table */
#define SFDP_SST_ID 0x01bf /* Manufacturer specific Table */
#define SFDP_PROFILE1_ID 0xff05 /* xSPI Profile 1.0 Table */
+#define SFDP_SCCR_MAP_ID 0xff87 /*
+ * Status, Control and Configuration
+ * Register Map.
+ */
#define SFDP_SIGNATURE 0x50444653U
#define SFDP_JESD216_MAJOR 1
@@ -172,6 +176,9 @@ struct sfdp_header {
#define PROFILE1_DWORD5_DUMMY_100MHZ GENMASK(11, 7)
#define PROFILE1_DUMMY_DEFAULT 20
+/* Status, Control and Configuration Register Map(SCCR) */
+#define SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE BIT(31)
+
struct sfdp_bfpt {
u32 dwords[BFPT_DWORD_MAX];
};
@@ -2434,6 +2441,45 @@ out:
return ret;
}
+/**
+ * spi_nor_parse_sccr() - Parse the Status, Control and Configuration Register
+ * Map.
+ * @nor: pointer to a 'struct spi_nor'
+ * @sccr_header: pointer to the 'struct sfdp_parameter_header'
describing
+ * the SCCR Map table length and version.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_parse_sccr(struct spi_nor *nor,
+ const struct sfdp_parameter_header *sccr_header)
+{
+ u32 *table, opcode, addr;
+ size_t len;
+ int ret, i;
+ u8 dummy;
+
+ len = sccr_header->length * sizeof(*table);
+ table = kmalloc(len, GFP_KERNEL);
+ if (!table)
+ return -ENOMEM;
+
+ addr = SFDP_PARAM_HEADER_PTP(sccr_header);
+ ret = spi_nor_read_sfdp(nor, addr, len, table);
+ if (ret)
+ goto out;
+
+ /* Fix endianness of the table DWORDs. */
+ for (i = 0; i < sccr_header->length; i++)
+ table[i] = le32_to_cpu(table[i]);
+
+ if (FIELD_GET(SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE, table[22]))
+ nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
+
+out:
+ kfree(table);
+ return ret;
+}
+
/**
* spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
* @nor: pointer to a 'struct spi_nor'
@@ -2539,6 +2585,9 @@ static int spi_nor_parse_sfdp(struct spi_nor *nor,
case SFDP_PROFILE1_ID:
err = spi_nor_parse_profile1(nor, param_header, params);
break;
+ case SFDP_SCCR_MAP_ID:
+ err = spi_nor_parse_sccr(nor, param_header);
+ break;
default:
break;
@@ -3584,6 +3633,9 @@ static int spi_nor_octal_dtr_enable(struct spi_nor *nor)
nor->write_proto == SNOR_PROTO_8_8_8_DTR))
return 0;
+ if (!(nor->flags & SNOR_F_IO_MODE_EN_VOLATILE))
+ return 0;
+
ret = nor->octal_dtr_enable(nor);
if (ret)
return ret;
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 8682368f2f..10c7b6e4c3 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -287,6 +287,7 @@ enum spi_nor_option_flags {
SNOR_F_USE_CLSR = BIT(5),
SNOR_F_BROKEN_RESET = BIT(6),
SNOR_F_SOFT_RESET = BIT(7),
+ SNOR_F_IO_MODE_EN_VOLATILE = BIT(8),
};
struct spi_nor;
--
2.17.1
