Hi all
I'm hoping that someone can help me here. I'm using the TQM8xxL module
with a MPC862 processor on board. With minor changes to the pin
configurations for the ethernet controller I have gotten U-boot and
Linux to work without any issues. However from my BDI2000 shell, with my
IMMR set to 0xFFF00000 (confirmed), I cannot do memory dumps for the
region 0xFFF00000 - 0xFFF02000. From FFF02000 (DP-RAM) the memory
accesses seem fine. The same goes for the u-boot shell. Obviously u-boot
and linux have managed to access these registers, else the system would
not start? How do I go about doing direct memory accesses to the MPC's
registers which are located from 0xFFF00000 to 0xFFF00DFF from either
u-boot or the BDI shell?
Regards
Flavio Pereira
** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
Hi Flavio,
on 862 the internal memory mapped registers are not like plane memory. Only several addresses can actualy be accessed. If you try no
access an non existant register address you cause a bus error.
For that reason you have to consult the manual before you access any address in the IMMR area and in most cases a simple dump tries
to access an area that is to large to avoid invalid accesses.
Regards, Stephan
-----Original Message-----
From: owner-linuxppc-embedded@lists.linuxppc.org
[mailto:owner-linuxppc-embedded@lists.linuxppc.org]On Behalf Of Flavio
Pereira
Sent: Mittwoch, 5. Februar 2003 13:48
To: LinuxPPC-Embedded
Subject: Accessing MPC862 registers
Hi all
I'm hoping that someone can help me here. I'm using the TQM8xxL module
with a MPC862 processor on board. With minor changes to the pin
configurations for the ethernet controller I have gotten U-boot and
Linux to work without any issues. However from my BDI2000 shell, with my
IMMR set to 0xFFF00000 (confirmed), I cannot do memory dumps for the
region 0xFFF00000 - 0xFFF02000. From FFF02000 (DP-RAM) the memory
accesses seem fine. The same goes for the u-boot shell. Obviously u-boot
and linux have managed to access these registers, else the system would
not start? How do I go about doing direct memory accesses to the MPC's
registers which are located from 0xFFF00000 to 0xFFF00DFF from either
u-boot or the BDI shell?
Regards
Flavio Pereira
** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/