[U-Boot-Users] MIPS build environment

[Thomas Sailer]

On Sat, 2005-01-29 at 18:08 +0100, Wolfgang Denk wrote:

> No, you're moving into the wrong  direction.  I  hereby  reject  this
> patch, and will do the same woth all other attempts that go into that
> direction.

Sorry for miscommunicating, I didn't mean to ask you to apply it, I
meant it to stimulate discussion, which succeeded :)

Now I think there's a misunderstanding. There are two parts of u-boot,
namely the part that runs off SDRAM and the part that runs off the ROM.
For both parts the decision whether PIC or fixed address code should be
used is independent.

You argue for PIC/relocatable code in the main u-boot part that runs off
SDRAM. Rightly so, IMO. The patch I posted applies however to the part
that runs off ROM (FLASH) (SDRAM doesn't even work before the call to
memsetup, because the SDRAM controller and cache aren't setup yet). Now
this code is typically located at the reset vector address, and this
address is normally fixed by the silicon/cpu architecture. For this part
of u-boot, relocatability is less useful. Now MIPS has a feature to
allow the machine to be booted from JTAG by relocating the reset vector
into a memory space that when accessed causes a JTAG transaction with
the debug PC to supply the data, so for this feature relocatability of
the ROM part of u-boot could be somewhat useful.

Tom