The EMMA2 (uPD61130) uses the NEC Vr4130 core,
wheras the EMMA2L (uPD61120)
uses a MIPS 4Kc core. The 4Kc is a
MIPS32-compliant core, but the Vr41xx family
predates the MIPS32 spec for the MMU interface, and
has some significant incompatibilities,
mostly due to the fact that the Vr4100's assume a
1K page granularity, versus 4K for the 4Kc
and almost all other MIPS processors. You
can't use the same MMU code for both chips.
One kernel needs to be configured for a "MIPS32"
CPU, the other for "R41xx".
----- Original Message -----
Sent: Wednesday, September 24, 2003 9:36
Subject: Page fault question
I?m currently porting vmlinux from
NEC?s EMMA2L platform to EMMA2. The problem I?m having is that linux
hangs when it attempts to do its first page fault: the page fault handler is
successfully called, the call to handle_mm_fault returns 2 (major fault)?but
then code execution appears to just stop. Linux is not completely dead,
however ? it still responds to a timer interrupt.
As the code for handling page
faults is standard code, and TLB hardware should be the same on EMMA2 as on
EMMA2L (where it works!), I don?t understand what?s gone wrong! Does
anyone have any ideas?
Thanks for your