PowerPC + SMP
stuart.yoder at conformative.com
Wed Apr 27 05:07:36 EST 2005
We've run into a few issues with U-boot, but they are not unsolveable--
-it doesn't provide an alternate execution path for the 2nd CPU when it
is started by the kernel
-U-boot needs to detect which CPU is executing
-U-boot on the 2nd CPU should not execute any platform/board specific
setup code-- this is stuff you only want to do once
-U-boot on the 2nd CPU cannot relocate itself to SDRAM because Linux is
already running there and assumes it owns all of memory
-it needs some way of getting to the Linux kernel entry point for
-it also appears that it should set up HID1 (other stuff??) for SMP
> -----Original Message-----
> From: Wolfgang Denk [mailto:wd at denx.de]
> Sent: Tuesday, April 26, 2005 12:35 PM
> To: Stuart Yoder
> Cc: 'linuxppc-dev list'
> Subject: Re: PowerPC + SMP
> In message <054301c54a6f$d1cf82b0$2f010a0a at foundation.com> you wrote:
> > I am using U-boot on my SMP system and U-boot is not SMP aware. Do
> > you
> Strictly speaking this statement is wrong.
> So far I am not aware of a port of U-Boot to a SMP system.
> If there was such a port, and if it was properly done,
> then U-Boot probably _were_ SMP aware.
> Best regards,
> Wolfgang Denk
> Software Engineering: Embedded and Realtime Systems, Embedded Linux
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email:
> wd at denx.de Every program has at least one bug and can be
> shortened by at least one instruction -- from which,
> by induction, one can deduce that every program can be
> reduced to one instruction which doesn't work.
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