/* set direct allocation base */
        bc->dio_p = 0x1000000;
        bc->d32_p = 0x1000000;


[snip]


        /*
         * Route all PCI bridge interrupts to the HEART ASIC. The idea is
         * that we cause the bridge to send an Xtalk write to a specified
         * interrupt register (0x80 for HEART, 0x90 for HUB) in a defined
         * widget. The actual IRQ support and masking is done elsewhere.
         */
        bridge->b_wid_int_upper = masterwid << 16;
        bridge->b_wid_int_lower = 0x00000080;


[snip]


        /*
         * We map the IRQs to slots in a straightforward way.
         */
[snip]

        bridge->b_int_device &= 0xFF000000;
        bridge->b_int_enable = 0x7FFFFE00;
        bridge->b_int_mode = 0x00000000;