Help needed with uboot for CHIP

[Gunjan Gupta]

Ok...

What about supporting SLC. I dont have a Chip pro, but are you sure that
the current logic works for that too?

Thanks & Regards
Gunjan Gupta

On Mon, Mar 22, 2021, 11:58 PM Maxime Ripard <maxime at cerno.tech> wrote:

> Hi,
>
> On Sun, Mar 21, 2021 at 08:04:08PM +0530, Gunjan Gupta wrote:
> > I figured out the why SPL was not loading U-Boot from NAND.
> >
> > Apparently the logic to use PIO instead of DMA that was introduced in
> > 6ddbb1e936c78cdef1e7395039fa7020c5c75326
> > <
> https://github.com/u-boot/u-boot/commit/6ddbb1e936c78cdef1e7395039fa7020c5c75326
> >
> > may
> > be was not as generic as it was supposed to be. I tried adding hexdump in
> > nand_read_page and found that on CHIP the logic was not reading and real
> > data. Instead all of the bytes were set to 0s.
> >
> > I have created a patch to provide an option to use the older version of
> > nand_read_page function that was present just before the above mentioned
> > commit.
> >
> > With the attached patches and some config changes the Upstream U-Boot
> works
> > fine on CHIP. I have tested the attached patches on CHIP with 8GB Hynix
> > nand along with the following extra configurations.
>
> An MLC NAND without proper support will work fine until it won't. I
> would strongly discourage you to use it.
>
> > CONFIG_MTD=y
> > CONFIG_CMD_MTD=y
> > CONFIG_CMD_MTDPARTS=y
> > CONFIG_MTDIDS_DEFAULT="nand0=sunxi-nand.0"
> >
> CONFIG_MTDPARTS_DEFAULT="mtdparts=sunxi-nand.0:4m(spl),4m(spl-backup),4m(uboot),4m(env),-(yaffs2)"
> > CONFIG_MTD_RAW_NAND=y
> > CONFIG_SYS_NAND_BLOCK_SIZE=0x400000
> > CONFIG_SYS_NAND_PAGE_SIZE=0x4000
> > CONFIG_SYS_NAND_OOBSIZE=0x680
> > CONFIG_ENV_IS_IN_NAND=y
> > CONFIG_ENV_SIZE=0x400000
> > CONFIG_ENV_OFFSET=0xc00000
> > CONFIG_FASTBOOT_FLASH_NAND=y
> > CONFIG_YAFFS2=y
> >
> > @Andre will it be possible to get the attached patches merged into the
> > U-Boot?
>
> And we definitely shouldn't make it easy
>
> Maxime
>