diff options
-rw-r--r-- | arch/m68k/mac/via.c | 34 |
1 files changed, 20 insertions, 14 deletions
diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c index 97996a48b04..7a2993bb092 100644 --- a/arch/m68k/mac/via.c +++ b/arch/m68k/mac/via.c @@ -253,22 +253,28 @@ void __init via_init(void) via2[vACR] &= ~0x03; /* disable port A & B latches */ } + /* Everything below this point is VIA2 only... */ + + if (rbv_present) + return; + /* - * Set vPCR for control line interrupts (but not on RBV) + * Set vPCR for control line interrupts. + * + * CA1 (SLOTS IRQ), CB1 (ASC IRQ): negative edge trigger. + * + * Macs with ESP SCSI have a negative edge triggered SCSI interrupt. + * Testing reveals that PowerBooks do too. However, the SE/30 + * schematic diagram shows an active high NCR5380 IRQ line. */ - if (!rbv_present) { - /* For all VIA types, CA1 (SLOTS IRQ) and CB1 (ASC IRQ) - * are made negative edge triggered here. - */ - if (macintosh_config->scsi_type == MAC_SCSI_OLD) { - /* CB2 (IRQ) indep. input, positive edge */ - /* CA2 (DRQ) indep. input, positive edge */ - via2[vPCR] = 0x66; - } else { - /* CB2 (IRQ) indep. input, negative edge */ - /* CA2 (DRQ) indep. input, negative edge */ - via2[vPCR] = 0x22; - } + + pr_debug("VIA2 vPCR is 0x%02X\n", via2[vPCR]); + if (macintosh_config->via_type == MAC_VIA_II) { + /* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, pos. edge */ + via2[vPCR] = 0x66; + } else { + /* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, neg. edge */ + via2[vPCR] = 0x22; } } |