lkml.org 
[lkml]   [2021]   [Jan]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH v2] mtd: spi-nor: macronix: enable 4-bit BP support for MX25L6405D
Date
Hi, Sieng,

On 12/8/20 3:57 AM, Sieng Piaw Liew wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>
> Enable 4-bit Block Protect support for MX256405D and its variants using
> the same ID.
>
> Tested on Innacom W3400V6 router with MX25L6406E chip.
> https://github.com/openwrt/openwrt/pull/3501
>
> Signed-off-by: Sieng Piaw Liew <liew.s.piaw@gmail.com>
> ---
> Changes in v2:
> - Add SPI_NOR_HAS_LOCK which SPI_NOR_4BIT_BP required.
>
> drivers/mtd/spi-nor/macronix.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/spi-nor/macronix.c b/drivers/mtd/spi-nor/macronix.c
> index 9203abaac229..033ede381673 100644
> --- a/drivers/mtd/spi-nor/macronix.c
> +++ b/drivers/mtd/spi-nor/macronix.c
> @@ -42,7 +42,9 @@ static const struct flash_info macronix_parts[] = {
> { "mx25l1606e", INFO(0xc22015, 0, 64 * 1024, 32, SECT_4K) },
> { "mx25l3205d", INFO(0xc22016, 0, 64 * 1024, 64, SECT_4K) },
> { "mx25l3255e", INFO(0xc29e16, 0, 64 * 1024, 64, SECT_4K) },
> - { "mx25l6405d", INFO(0xc22017, 0, 64 * 1024, 128, SECT_4K) },
> + { "mx25l6405d", INFO(0xc22017, 0, 64 * 1024, 128,
> + SECT_4K | SPI_NOR_HAS_LOCK |
> + SPI_NOR_4BIT_BP) },

I've read again the datasheet[1], and to me it looks like we
don't support the locking scheme for this flash.
What mx25l6405d calls BP3, we refer to as Top/Bottom support (TB bit).
The problem that I see is that mx25l6405d uses some kind of twisted
TB bit.

For example, for BP3=1, BP2=0, BP1=0, BP0=1, the flash's datasheet
states that the lower half blocks are protected (0th-63th), while in
our code we would expect that just the lower first two blocks to be
protected (0th and 1st). We need new support for this flash.

Cheers,
ta

[1] https://www.macronix.com/Lists/Datasheet/Attachments/7309/MX25L6405D,%203V,%2064Mb,%20v1.5.pdf

> { "mx25u2033e", INFO(0xc22532, 0, 64 * 1024, 4, SECT_4K) },
> { "mx25u3235f", INFO(0xc22536, 0, 64 * 1024, 64,
> SECT_4K | SPI_NOR_DUAL_READ |
> --
> 2.17.1
>

\
 
 \ /
  Last update: 2021-01-23 13:21    [W:0.092 / U:0.252 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site