On Sat, Oct 10, 2009 at 4:58 AM, Torin Ford
<torin@xxxxxxxxxxxx> wrote:
Hey All. I'm using petalinux-0.40-rc4. Whenever I try to use the
reboot command, I get the following output:
Restarting system.
Machine restart...
<stack trace dumped here>
Any ideas why it dumps and doesn't just reset?
MicroBlaze lacks a in-built soft-reset capability, so it's not possible for the kernel to implement a generic reset. Instead, the MicroBlaze kernel hook for it (down in arch/microblaze/kernel/setup.c, machine_restart()) defaults to a stack dump and then spins forever.
One approach is to add a GPIO with its output connected to the AUX input of the proc_sys_reset instance in the system. Then, in the machine_restart() function simply toggle that GPIO bit to achieve a reset.
If I boot into u-boot
and issue the reset command, it properly resets the FPGA.
From memory u-boot simply jumps to the reset vector to achieve reset. Works OK for u-boot but not sufficiently safe for the Linux kernel, you really need a hardware reset to make sure all peripherals are reset, the CPU state cleaned etc.
Regards,
John