[PATCH v7 15/20] mtd: spi-nor: sfdp: detect Soft Reset sequence support from BFPT

From: Pratyush Yadav
Date: Fri May 22 2020 - 06:14:44 EST


A Soft Reset sequence will return the flash to Power-on-Reset (POR)
state. It consists of two commands: Soft Reset Enable and Soft Reset.
Find out if the sequence is supported from BFPT DWORD 16.

Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx>
---
drivers/mtd/spi-nor/core.h | 1 +
drivers/mtd/spi-nor/sfdp.c | 4 ++++
drivers/mtd/spi-nor/sfdp.h | 2 ++
3 files changed, 7 insertions(+)

diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 6338d32a0d77..79ce952c0539 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -26,6 +26,7 @@ enum spi_nor_option_flags {
SNOR_F_HAS_SR_TB_BIT6 = BIT(11),
SNOR_F_HAS_4BIT_BP = BIT(12),
SNOR_F_HAS_SR_BP3_BIT6 = BIT(13),
+ SNOR_F_SOFT_RESET = BIT(14),
};

struct spi_nor_read_command {
diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index 9fd3d8d9a127..11109969dc3a 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -618,6 +618,10 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
break;
}

+ /* Soft Reset support. */
+ if (bfpt.dwords[BFPT_DWORD(16)] & BFPT_DWORD16_SOFT_RST)
+ nor->flags |= SNOR_F_SOFT_RESET;
+
/* Stop here if JESD216 rev B. */
if (bfpt_header->length == BFPT_DWORD_MAX_JESD216B)
return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt,
diff --git a/drivers/mtd/spi-nor/sfdp.h b/drivers/mtd/spi-nor/sfdp.h
index e15e30796d62..d1d43ee09a0a 100644
--- a/drivers/mtd/spi-nor/sfdp.h
+++ b/drivers/mtd/spi-nor/sfdp.h
@@ -84,6 +84,8 @@ struct sfdp_bfpt {
#define BFPT_DWORD15_QER_SR2_BIT1_NO_RD (0x4UL << 20)
#define BFPT_DWORD15_QER_SR2_BIT1 (0x5UL << 20) /* Spansion */

+#define BFPT_DWORD16_SOFT_RST BIT(12)
+
#define BFPT_DWORD18_CMD_EXT_MASK GENMASK(30, 29)
#define BFPT_DWORD18_CMD_EXT_REP (0x0UL << 29) /* Repeat */
#define BFPT_DWORD18_CMD_EXT_INV (0x1UL << 29) /* Invert */
--
2.26.2