[U-Boot-Users] MPC8266ADS patch

Rune Torgersen runet at innovsys.com
Thu Sep 11 23:05:50 CEST 2003

> When Linux 
> boots, it assumes the BIOS is brain-dead and reconfigures 
> everything. The BCSR and IMMR will be relocated to what makes 
> sense for that operating environment.

This is not enirely true for PPC Linux. It is true for x86. On PPC, Linux
assumes that the BIOS or bootloader initalizes all the board or CPU specific
hardware. Like the FCCs for ehternet, serial ports (for initial debug
output), IO pins used by FCCs, and serial ports.(linux doesn't touch thesse)

Some of the meory map (specifically where the IMMR and to a lesser extent
BCSR) Linux depends on the bootloader to tell it where they are.

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