[U-Boot] [PATCH v4 1/3] NAND boot: MPC8536DS support

[Kumar Gala]

On Sep 23, 2009, at 2:20 AM, Mingkai Hu wrote:

> MPC8536E can support booting from NAND flash which uses the
> image u-boot-nand.bin. This image contains two parts: a 4K
> NAND loader and a main U-Boot image. The former is appended
> to the latter to produce u-boot-nand.bin. The 4K NAND loader
> includes the corresponding nand_spl directory, along with the
> code twisted by CONFIG_NAND_SPL. The main U-Boot image just
> like a general U-Boot image except the parts that included by
> CONFIG_SYS_RAMBOOT.
>
> When power on, eLBC will automatically load from bank 0 the
> 4K NAND loader into the FCM buffer RAM where CPU can execute
> the boot code directly. In the first stage, the NAND loader
> copies itself to RAM or L2SRAM to free up the FCM buffer RAM,
> then loads the main image from NAND flash to RAM or L2SRAM
> and boot from it.
>
> This patch implements the NAND loader to load the main image
> into L2SRAM, so the main image can configure the RAM by using
> SPD EEPROM. In the first stage, the NAND loader copies itself
> to the second to last 4K address space, and uses the last 4K
> address space as the initial RAM for stack.
>
> Obviously, the size of L2SRAM shouldn't be less than the size
> of the image used. If so, the workaround is to generate another
> image that includes the code to configure the RAM by SPD and
> load it to L2SRAM first, then relocate the main image to RAM
> to boot up.
>
> Signed-off-by: Mingkai Hu <Mingkai.hu at freescale.com>
> ---
>
> Change over v3:
> - Intergrated Scott's comments.
> - Intergrated Wolfgang's comments.

applied to 85xx

- k