[PATCH v16 3/8] mtd: spi-nor: Do not change nor->addr_nbytes at SFDP parsing time

tkuw584924 at gmail.com tkuw584924 at gmail.com
Thu Jun 9 01:57:40 PDT 2022


From: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>

At the SFDP parsing time we should not change members of struct spi_nor,
but instead fill members of struct spi_nor_flash_parameters which could
later on be used by callers. The caller will then decide if SFDP params
should be used and more importantly when they should be used. Clean the
code flow and don't initialize nor->addr_nbytes at SFDP parsing time.

Signed-off-by: Tudor Ambarus <tudor.ambarus at microchip.com>
Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
Reviewed-by: Michael Walle <michael at walle.cc>
Tested-by: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
---
Changes in v16:
  - Stop restoring nor->addr_nbytes to uninitialized state

 drivers/mtd/spi-nor/core.c | 5 ++---
 drivers/mtd/spi-nor/core.h | 2 ++
 drivers/mtd/spi-nor/issi.c | 2 +-
 drivers/mtd/spi-nor/sfdp.c | 8 ++++----
 4 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 14b6b1f38b69..70a9570fc2d4 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -2251,8 +2251,8 @@ static int spi_nor_default_setup(struct spi_nor *nor,
 
 static int spi_nor_set_addr_nbytes(struct spi_nor *nor)
 {
-	if (nor->addr_nbytes) {
-		/* already configured from SFDP */
+	if (nor->params->addr_nbytes) {
+		nor->addr_nbytes = nor->params->addr_nbytes;
 	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
 		/*
 		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
@@ -2497,7 +2497,6 @@ static void spi_nor_sfdp_init_params_deprecated(struct spi_nor *nor)
 
 	if (spi_nor_parse_sfdp(nor)) {
 		memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
-		nor->addr_nbytes = 0;
 		nor->flags &= ~SNOR_F_4B_OPCODES;
 	}
 }
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 5eff3f636416..972e54ecfda9 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -340,6 +340,7 @@ struct spi_nor_otp {
  * @writesize		Minimal writable flash unit size. Defaults to 1. Set to
  *			ECC unit size for ECC-ed flashes.
  * @page_size:		the page size of the SPI NOR flash memory.
+ * @addr_nbytes:	number of address bytes to send.
  * @rdsr_dummy:		dummy cycles needed for Read Status Register command
  *			in octal DTR mode.
  * @rdsr_addr_nbytes:	dummy address bytes needed for Read Status Register
@@ -372,6 +373,7 @@ struct spi_nor_flash_parameter {
 	u64				size;
 	u32				writesize;
 	u32				page_size;
+	u8				addr_nbytes;
 	u8				rdsr_dummy;
 	u8				rdsr_addr_nbytes;
 
diff --git a/drivers/mtd/spi-nor/issi.c b/drivers/mtd/spi-nor/issi.c
index 23e331cc42a9..4d44f2510889 100644
--- a/drivers/mtd/spi-nor/issi.c
+++ b/drivers/mtd/spi-nor/issi.c
@@ -20,7 +20,7 @@ is25lp256_post_bfpt_fixups(struct spi_nor *nor,
 	 */
 	if ((bfpt->dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) ==
 		BFPT_DWORD1_ADDRESS_BYTES_3_ONLY)
-		nor->addr_nbytes = 4;
+		nor->params->addr_nbytes = 4;
 
 	return 0;
 }
diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index 61ae8c8c5237..3a48173a2d78 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -462,11 +462,11 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 	switch (bfpt.dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) {
 	case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
 	case BFPT_DWORD1_ADDRESS_BYTES_3_OR_4:
-		nor->addr_nbytes = 3;
+		params->addr_nbytes = 3;
 		break;
 
 	case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
-		nor->addr_nbytes = 4;
+		params->addr_nbytes = 4;
 		break;
 
 	default:
@@ -653,7 +653,7 @@ static u8 spi_nor_smpt_addr_nbytes(const struct spi_nor *nor, const u32 settings
 		return 4;
 	case SMPT_CMD_ADDRESS_LEN_USE_CURRENT:
 	default:
-		return nor->addr_nbytes;
+		return nor->params->addr_nbytes;
 	}
 }
 
@@ -1098,7 +1098,7 @@ static int spi_nor_parse_4bait(struct spi_nor *nor,
 	 * Spansion memory. However this quirk is no longer needed with new
 	 * SFDP compliant memories.
 	 */
-	nor->addr_nbytes = 4;
+	params->addr_nbytes = 4;
 	nor->flags |= SNOR_F_4B_OPCODES | SNOR_F_HAS_4BAIT;
 
 	/* fall through */
-- 
2.25.1




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