Re: [Ltib] phy3250 uboot environment in eeprom

[Mike RA9FTM]

Hello, Kevin.

Thank you for your message. I am developing reliable device on lpc3250 core.
kickstart is placed to the EEPROM now, because NAND flash is not reliable.
S1L, u-boot and linux kernel will be placed in NAND by following way:

block 1: S1L S1L S1L    u-boot u-boot u-boot    kernel kernel kernel

kickstart is modified and now it counts CRC checksum for S1L, u-boot and kernel, compares it with CRC saved in the EEPROM. It is still less than 15,5 kb.

so, modified kickstart algorithm should be as follows:
1. find unbroken S1L
2. find unbroken uboot
3. modify S1L config in EEPROM so it will link to unbroken uboot
4. find unbroken kernel
5. modify uboot config so t will load unbroken linux kernel

6. copy S1L to RAM and start it  (this is default kickstart functionality)

I have already modified S1L so it is now reads from EEPROM number of block where u-boot is placed and loads it from that place.



I have seen your u-boot patch, especially in board/phy3250/lowlevels_init.c function phy3250_get_board_info.
For example, here is implemented mac address reading from EEPROM, but when I run "bdinfo" command, it shows: ethaddr     = 00:00:00:00:00:00 Any suggestions? Where mac address saves?

So, I think it is possible to implement reading address from EEPROM, where unbroken kernel is placed.
It is also need to modify include/configs/phy3250.h this string for all three u-boot images in NAND, this string:

#define CONFIG_ENV_OFFSET    0x168000 /* Block 90 */

The root file system also will be placed in NAND and it will be jffs2.

With best regards, 
 Mike

2009/12/16 Kevin Wells <address@hidden>

Hi Mike,

There is some simple code in that port of u-boot for
reading a SPI based EEPROM device that can easily be
updated with additional write support. This is
initially used with the SPI EEPROM to get board data.
You can also get a rw example at the chip vendor's
website.

I can't help you too much with the u-boot implemention,
but you'll also probably want to look at the u-boot
spi or mtd support.

Kevin

> Subject: Re: [Ltib] phy3250 uboot environment in eeprom

>
> Hi Mike,
>
> You may get some help on the u-boot list, maybe someone has done this
> before?
>
> As I recall the u-boot configuration data is often saved in it's own
> Flash sector, so you could look a this code and re-work it (the savenenv
> command).
>
> Regards, Stuart
>
> Mike RA9FTM wrote:
> > Hello
> >
> > I whant to save phy3250 uboot configuration data in EEPROM, not in NAND
> > flash.
> > I think it is possible with some u-boot code modification.
> > So, is it really hard to implement this feature or not?
> >
> > I think that most hard is to load SPI driver...
> >
> >
> > --
> > 73! Mike RA9FTM
> >
> >
>
>

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-- 
73! Mike RA9FTM