sh7750.c:672: sh7750_mmct_writel: Assertion `0' failed.

[Khem Raj]

qemu 0.12.5 on ubuntu ends up with this error when booting a SH4 machine

usb 1-1: Manufacturer: 1
INIT: version 2.86 booting
Error, no support currently for 8 bpp frame buffers
Trying to change pixel format...
Please wait: booting...
Switched to a 32 bpp 8,8,8 frame buffer
Starting udev
Remounting root file system...
Caching udev devnodes
Populating dev cache
root: mount: mount point /proc/bus/usb does not exist
qemu-system-sh4: /build/buildd/qemu-kvm-0.12.3+noroms/hw/sh7750.c:672: sh7750_mmct_writel: Assertion `0' failed.
Aborted

the commandline is

qemu-system-sh4 -M r2d --snapshot -m 512 -kernel zImage-qemush4.bin -usb -usbdevice wacom-tablet --no-reboot -localtime -monitor null -serial vc -serial stdio -drive file=/tmp/console-image-qemush4.ext3 -append 'console=ttySC1 noiotrap earlyprintk=sh-sci.1 root=/dev/sda rw debug user_debug=-1' -net none --nographic

The kernel and root file system images are found on

http://www.uclibc.org/~kraj/qemush4/console-image-qemush4.ext3
http://www.uclibc.org/~kraj/qemush4/zImage-qemush4.bin

[Aurelien Jarno (aurel32)]

The problem there is that for some unknown reasons your kernel is flushing the iTLB through the memory-mmaped interface (which is not yet implemented) instead of using the MMUCR.TI bit.

I was actually playing with the SH4 MMU code this week-end and wrote this missing part of the code, but I was unable to test it. Your QEMU image helped me a lot, and I confirm that my code was correct.

I have just commited the patch qemu HEAD.

[Khem Raj (khem-raj)]

yes I backported these fixes on top of 0.12.5 and now I can boot the image successfully. thanks for quick turnaround.