Yes, this is correct: "In User mode, the control bits of the CPSR are protected
from change, so only the condition code flags of the CPSR can be changed. In
other (privileged) modes the entire CPSR can be changed." If the supervisor
mode is the reason for the troubles, then I think it is worth, to modify the
software.
----- Original Message -----
From: Michael Sevakis
To: Rockbox development
Sent: Wednesday, May 09, 2007 5:40 PM
Subject: Re: PPs running in supervisor mode
Wouldn't software interrupts be needed to call code to switch to a supervisor
mode when needed? I _am_ rather new to ARM and such but it's my educated guess
atm based on our other big CPU. I fear major complication from it.
----- Original Message -----
From: Antonius Hellmann
To: Rockbox development
Sent: Wednesday, May 09, 2007 2:03 AM
Subject: PPs running in supervisor mode
One idea, why we have these troubles with interrupt handling on the PP
devices is, that probably the supervisor mode has some issues with interrupt
switching? I understand, that the supervisor mode makes it easy to do register
manipulations. But it might be more safe to run the rockbox application code in
user mode.
