[Letux-kernel] [PATCH 0/3] mtd: Ingenic NAND fix for JZ4740

H. Nikolaus Schaller hns at goldelico.com
Sun Nov 7 14:47:43 CET 2021


Hi Paul,

> Am 09.10.2021 um 20:49 schrieb Paul Cercueil <paul at crapouillou.net>:
> 
> Hi,
> 
> Looks like NAND support has been broken on the JZ4740 SoC for a while;

Yes, I remember someone telling that something was fundamentally broken
and impossible to be fixed a while ago.

> it looks like it comes from the fact that the "hw_oob_first" mechanism
> was dropped from the NAND core and moved to the Davinci driver.
> 
> It turns out the JZ4740 SoC needs it too; I didn't notice it when
> writing the new ingenic-nand driver (to replace the old jz4740-nand
> driver) most likely because my Device Tree had the "nand-ecc-mode" set
> to "hw_oob_first".
> 
> I am not very sure about patch [1/3]; to me the original code does not
> make sense, and it didn't work out-of-the-box on the JZ4740 without it.
> By applying patch [1/3] the function nand_read_page_hwecc_oob_first()
> can be reused for the JZ4740 SoC as well. But I did not test patch [1/3]
> on Davinci.

would this also work for jz4780 NAND?

BR,
Nikolaus



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