G4 and overriding the L2 Backside Cache


Subject: G4 and overriding the L2 Backside Cache
From: Jason Gan (Jason@hspace.net)
Date: Mon Jul 09 2001 - 05:36:18 MDT


Hi,

I've successfully followed what some other people have done,
and overriden the L2 backside cache for the G4 in Linuxppc.

I have a Newer Tech G4 upgrade card installed on my Powermac 8500.

There are two issues about G4:

1) The BootX extension will not give you the option to
   check the "Enable G3 Backside Cache" option,
   because it can tell that it is not a G3 upgrade card.

2) You can't use the GrabG3CacheSetting.sea.bin program
   to grab the G3 Cache setting because it can tell that
   you don't have a G3 upgrade card.

What to do:

1) Download the PowerLogix G3/G4 Profiler, and run it
   (enable the backside cache in the program and let it
   write the G3 Cache setting into the BootX Preferences.
   (Make a backup of BootX Preferences.)

2) Download ResEdit.

3) Use ResEdit to open BootX App and edit the
   option for Set G3 Cache to have the value of 1.

4) Run BootX App, and save to prefs. You now have a
   BootX Prefs which will enable the backside cache
   in Linuxppc.

5) (Make a backup of your "custom-designed" BootX Prefs
   in case it gets corrupted and you don't remember
   what to do.)

6) Reboot and use Linuxppc...

7) To check that the G4 backside cache is enabled in
   Linuxppc, open the command line window and enter

   dmesg | grep L2CR

   It should say: "L2CR overriden (0xb9080000),
   backside cache is enabled"



This archive was generated by hypermail 2a24 : Mon Jul 09 2001 - 04:41:17 MDT