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* [PATCH] mtd: spi-nor: Add 4-byte address support for is25lp256
@ 2018-08-24 14:41 Liu Xiang
  2018-11-11  8:45 ` Boris Brezillon
  0 siblings, 1 reply; 3+ messages in thread
From: Liu Xiang @ 2018-08-24 14:41 UTC (permalink / raw)
  To: linux-mtd
  Cc: linux-kernel, marek.vasut, dwmw2, computersforpeace,
	boris.brezillon, richard, liuxiang_1999, Liu Xiang

The is25lp256 supports 4-byte opcodes and quad output.
In is25lp256, the DWORD1 of JEDEC Basic Flash Parameter Header
is 0xfff920e5. So the DWORD1[18:17] Address Bytes bits are 0b00,
means that 3-Byte only addressing. Now this limits nor->addr_width
to 3 and makes it inpossible to access the address above 16MB.
I think the size of flash is the most important judgement for
nor->addr_width. Once the size is larger than 16MB, nor->addr_width
must be 4. This can avoid the bad situation that manufacturer sets
incorrect value of register.

Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
---
 drivers/mtd/spi-nor/spi-nor.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index d9c368c..0203b09 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1065,7 +1065,7 @@ static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 	{ "is25lp128",  INFO(0x9d6018, 0, 64 * 1024, 256,
 			SECT_4K | SPI_NOR_DUAL_READ) },
 	{ "is25lp256",  INFO(0x9d6019, 0, 64 * 1024, 512,
-			SECT_4K | SPI_NOR_DUAL_READ) },
+			SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | SPI_NOR_4B_OPCODES) },
 	{ "is25wp032",  INFO(0x9d7016, 0, 64 * 1024,  64,
 			SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
 	{ "is25wp064",  INFO(0x9d7017, 0, 64 * 1024, 128,
@@ -2926,16 +2926,16 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
 	if (ret)
 		return ret;
 
-	if (nor->addr_width) {
-		/* already configured from SFDP */
-	} else if (info->addr_width) {
-		nor->addr_width = info->addr_width;
-	} else if (mtd->size > 0x1000000) {
+	if (mtd->size > 0x1000000) {
 		/* enable 4-byte addressing if the device exceeds 16MiB */
 		nor->addr_width = 4;
 		if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
-		    info->flags & SPI_NOR_4B_OPCODES)
+			info->flags & SPI_NOR_4B_OPCODES)
 			spi_nor_set_4byte_opcodes(nor, info);
+	} else if (nor->addr_width) {
+		/* already configured from SFDP */
+	} else if (info->addr_width) {
+		nor->addr_width = info->addr_width;
 	} else {
 		nor->addr_width = 3;
 	}
-- 
1.9.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] mtd: spi-nor: Add 4-byte address support for is25lp256
  2018-08-24 14:41 [PATCH] mtd: spi-nor: Add 4-byte address support for is25lp256 Liu Xiang
@ 2018-11-11  8:45 ` Boris Brezillon
  0 siblings, 0 replies; 3+ messages in thread
From: Boris Brezillon @ 2018-11-11  8:45 UTC (permalink / raw)
  To: Liu Xiang
  Cc: linux-mtd, richard, linux-kernel, marek.vasut, liuxiang_1999,
	computersforpeace, dwmw2

Hi Liu,

On Fri, 24 Aug 2018 22:41:41 +0800
Liu Xiang <liu.xiang6@zte.com.cn> wrote:

> The is25lp256 supports 4-byte opcodes and quad output.
> In is25lp256, the DWORD1 of JEDEC Basic Flash Parameter Header
> is 0xfff920e5. So the DWORD1[18:17] Address Bytes bits are 0b00,
> means that 3-Byte only addressing. Now this limits nor->addr_width
> to 3 and makes it inpossible to access the address above 16MB.
> I think the size of flash is the most important judgement for
> nor->addr_width. Once the size is larger than 16MB, nor->addr_width
> must be 4. This can avoid the bad situation that manufacturer sets
> incorrect value of register.

Please split this patch:
- Add 4B_OPCODES flag to is25lp256
- Rework the ->addr_width selection logic (more about that below).

> 
> Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
> ---
>  drivers/mtd/spi-nor/spi-nor.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index d9c368c..0203b09 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -1065,7 +1065,7 @@ static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
>  	{ "is25lp128",  INFO(0x9d6018, 0, 64 * 1024, 256,
>  			SECT_4K | SPI_NOR_DUAL_READ) },
>  	{ "is25lp256",  INFO(0x9d6019, 0, 64 * 1024, 512,
> -			SECT_4K | SPI_NOR_DUAL_READ) },
> +			SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | SPI_NOR_4B_OPCODES) },
>  	{ "is25wp032",  INFO(0x9d7016, 0, 64 * 1024,  64,
>  			SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
>  	{ "is25wp064",  INFO(0x9d7017, 0, 64 * 1024, 128,
> @@ -2926,16 +2926,16 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
>  	if (ret)
>  		return ret;
>  
> -	if (nor->addr_width) {
> -		/* already configured from SFDP */
> -	} else if (info->addr_width) {
> -		nor->addr_width = info->addr_width;
> -	} else if (mtd->size > 0x1000000) {
> +	if (mtd->size > 0x1000000) {
>  		/* enable 4-byte addressing if the device exceeds 16MiB */
>  		nor->addr_width = 4;
>  		if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
> -		    info->flags & SPI_NOR_4B_OPCODES)
> +			info->flags & SPI_NOR_4B_OPCODES)
>  			spi_nor_set_4byte_opcodes(nor, info);
> +	} else if (nor->addr_width) {
> +		/* already configured from SFDP */
> +	} else if (info->addr_width) {
> +		nor->addr_width = info->addr_width;
>  	} else {
>  		nor->addr_width = 3;
>  	}

We'd rather return an error and warn users when nor->addr_width does not
match the device size than fix this mismatch silently.

Regards,

Boris

^ permalink raw reply	[flat|nested] 3+ messages in thread

* [PATCH] mtd: spi-nor: Add 4-byte address support for is25lp256
@ 2018-08-24 14:40 Liu Xiang
  0 siblings, 0 replies; 3+ messages in thread
From: Liu Xiang @ 2018-08-24 14:40 UTC (permalink / raw)
  To: linux-mtd
  Cc: linux-kernel, marek.vasut, dwmw2, computersforpeace,
	boris.brezillon, richard, Liu Xiang

The is25lp256 supports 4-byte opcodes and quad output.
In is25lp256, the DWORD1 of JEDEC Basic Flash Parameter Header
is 0xfff920e5. So the DWORD1[18:17] Address Bytes bits are 0b00,
means that 3-Byte only addressing. Now this limits nor->addr_width
to 3 and makes it inpossible to access the address above 16MB.
I think the size of flash is the most important judgement for
nor->addr_width. Once the size is larger than 16MB, nor->addr_width
must be 4. This can avoid the bad situation that manufacturer sets
incorrect value of register.

Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
---
 drivers/mtd/spi-nor/spi-nor.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index d9c368c..0203b09 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1065,7 +1065,7 @@ static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 	{ "is25lp128",  INFO(0x9d6018, 0, 64 * 1024, 256,
 			SECT_4K | SPI_NOR_DUAL_READ) },
 	{ "is25lp256",  INFO(0x9d6019, 0, 64 * 1024, 512,
-			SECT_4K | SPI_NOR_DUAL_READ) },
+			SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | SPI_NOR_4B_OPCODES) },
 	{ "is25wp032",  INFO(0x9d7016, 0, 64 * 1024,  64,
 			SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
 	{ "is25wp064",  INFO(0x9d7017, 0, 64 * 1024, 128,
@@ -2926,16 +2926,16 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
 	if (ret)
 		return ret;
 
-	if (nor->addr_width) {
-		/* already configured from SFDP */
-	} else if (info->addr_width) {
-		nor->addr_width = info->addr_width;
-	} else if (mtd->size > 0x1000000) {
+	if (mtd->size > 0x1000000) {
 		/* enable 4-byte addressing if the device exceeds 16MiB */
 		nor->addr_width = 4;
 		if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
-		    info->flags & SPI_NOR_4B_OPCODES)
+			info->flags & SPI_NOR_4B_OPCODES)
 			spi_nor_set_4byte_opcodes(nor, info);
+	} else if (nor->addr_width) {
+		/* already configured from SFDP */
+	} else if (info->addr_width) {
+		nor->addr_width = info->addr_width;
 	} else {
 		nor->addr_width = 3;
 	}
-- 
1.9.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

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2018-11-11  8:45 ` Boris Brezillon
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2018-08-24 14:40 Liu Xiang

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