[U-Boot] [mips] malta configuration works in qemu-1.5 does not in qemu-1.6

[Alon Bar-Lev]

On Mon, Nov 11, 2013 at 12:25 PM, Gabor Juhos <juhosg at openwrt.org> wrote:
>
> 2013.11.11. 10:52 keltezéssel, Daniel Schwierzeck írta:
> > 2013/11/10 Alon Bar-Lev <alon.barlev at gmail.com>:
> >> Hello,
> >>
> >> master is: 15c5cdf from Fri Nov 8 15:25:29 2013 -0500
> >> u-boot-2013.10
> >>
> >> Working in qemu-1.5.3.
> >> Does not work in qemu-1.6.1.
> >>
> >> The command prompt is not displayed, 100% cpu consumption.
> >>
> >> ---
> >> $ qemu-system-mips -M malta -nographic -drive if=pflash,file=/tmp/flash -m
> >> 256
> >>
> >>
> >> U-Boot 2013.10-00249-g15c5cdf (Nov 10 2013 - 18:00:48)
> >>
> >> Board: MIPS Malta CoreLV (Qemu)
> >> DRAM:  256 MiB
> >> ---
> >>
> >> Any idea what the difference? any fix pending somewhere?
> >>
> >
> > it is obviously am upstream change in qemu, which requires a fix in u-boot.
> >
> > Paul or Gabor, do you have an idea?
>
> It is broken since the following change in qemu:
>
> commit a427338b222b43197c2776cbc996936df0302f51
> Author: Paul Burton <paul.burton at imgtec.com>
> Date:   Fri Jun 14 08:30:44 2013 +0100
>
>     mips_malta: correct reading MIPS revision at 0x1fc00010
>
>     Rather than modifying the BIOS code at its original location, copy it
>     for the 0x1fc00000 region & modify the copy. This means the original
>     ROM code is correctly readable at 0x1e000010 whilst the MIPS revision
>     is readable at 0x1fc00010.
>
>     Additionally the code previously operated on target memory which would
>     later be overwritten by the BIOS image upon CPU reset if the -bios
>     argument was used to specify the BIOS image. This led to the written
>     MIPS revision being lost. Copying using rom_copy when -bios is used
>     fixes this issue.
>
>     Signed-off-by: Paul Burton <paul.burton at imgtec.com>
>     Signed-off-by: Leon Alrae <leon.alrae at imgtec.com>
>     Signed-off-by: Aurelien Jarno <aurelien at aurel32.net>
>
> Due to that change, we are getting a CPU exception while probing the
> flash at the 0x1fc00000 address.
>
> Changing the MALTA_FLASH_BASE constant to 0x1e000000 in
> 'arch/mips/include/asm/malta.h' fixes the problem. I will send a patch for that.
>
> -Gabor

Thanks for quick response!
I confirm this works in qemu-1.5 and qemu-1.6.

Regards,
Alon Bar-Lev.