Re: CPCI-405 port (PPC405GP)

In message [off-list ref] you wrote:

We (or at least I :-) make subtle changes to the parameters passed to
the kernel from the bootloaders from time to time.  This means people
with PPCboot roms have to change them any time this is done.  One of

Changing parameters passed to the kernel is trivial in PPCBoot.  Much
simpler  than with the bootloader where you have to recompile code to
get new default settings.

the purposes of the bootloader is to isolate these changes into the
bootloader.

As long as you don't create incompatible  _interfaces_  there  is  no
problem.

The bootloader is a critical part to initializing the environment for
the kernel.  With all of the MMU futzing around we do trying to get
Linux running, Ben and I have discussed yet another better bootloader
method to move some of this around between the bootloader and the
kernel start up.  There are also initrd and command line things done
by the bootloader (among other board specific initialization).  It's
more than whether or not we all use bi_recs.

Please keep in mind that PPCBoot exists, and is used on MANY  boards.
Even  when you don't use it yourself, I ask you not to break compati-
bility without GOOD reason. Also, I'd appreciate a little  discussion
with  the PPCBoot folks before such changes happen. You know where to
find us.

We don't object against switching to bi_recs - as  soon  as  somebody
cares to document how they are going to look like. So far I have seen
only  vague statements about something completely new in 2.5, and the
statement that they will NOT be an issue in 2.4.

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
As far as the laws of mathematics refer to reality, they are not cer-
tain, and as far as they are certain, they do not refer  to  reality.
                                                   -- Albert Einstein

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On Sun, Sep 23, 2001 at 08:01:18PM +0200, Wolfgang Denk wrote:

In message [off-list ref] you wrote:

quoted

the purposes of the bootloader is to isolate these changes into the
bootloader.

As long as you don't create incompatible  _interfaces_  there  is  no
problem.

Well, 2.5/2.6 _will_ be incompatible with 2.4.  But it should also be
possible for bootloaders to work for both.

quoted

The bootloader is a critical part to initializing the environment for
the kernel.  With all of the MMU futzing around we do trying to get
Linux running, Ben and I have discussed yet another better bootloader
method to move some of this around between the bootloader and the
kernel start up.  There are also initrd and command line things done
by the bootloader (among other board specific initialization).  It's
more than whether or not we all use bi_recs.

Please keep in mind that PPCBoot exists, and is used on MANY  boards.
Even  when you don't use it yourself, I ask you not to break compati-
bility without GOOD reason. Also, I'd appreciate a little  discussion
with  the PPCBoot folks before such changes happen. You know where to
find us.

Well, this was on linuxppc-dev at least once.  Possibly twice.  And at
least once more before we actually do this.  2.5 will be incompatible
since everyone whose spoken before has agreeded that the current methods
aren't 100%.  If you wanna make a case for moving everyone to the way
PPCBoot talks to the kernel, please do.

--
Tom Rini (TR1265)
http://gate.crashing.org/~trini/

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