cascading 8259 interrupts

Frank frannk_m1 at
Sat Sep 18 07:50:20 EST 2004

I am having problems getting the 8259 interrupts setup on my
mpc8245 based board. here is what I have:
EPIC interrupt 0: ethernet controller
EPIC interrupt 1: unused at this time
EPIC interrupt 2: 8259 PIC controller
EPIC interrupt 3: internal uart

I have the ethernet and urat working just fine. I can NFS mount
my root directory accross the network and I console I/O working
just fine. The problem is when I try to cascade the 8259 PIC to
interrupt 2, Linux hangs when booting. I have tried using the
sandpoint board as a model but it doesn't cacscade 8259
interrupts to EPIC interrupt2, it uses EPIC interrupt 0
according to the comments. 
How can I cacscade the 8259 to my EPIC interrupt 2???
Here's my code in my baord_setup.c:

   openpic_set_sources(0, 2, OpenPIC_Addr + 0x10200);
   openpic_set_sources(2, 1, OpenPIC_Addr + 0x10240);
   openpic_set_sources(3, 1, OpenPIC_Addr + 0x11120);

   openpic_hookup_cascade(18, "8259 cascade to EPIC",

        for ( i = 2 ; i < 3 ; i++ )
             irq_desc[i].handler = &i8259_pic;

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