[PATCH gnumach] ioapic.c: Fix default polarity and trigger mode for irqs

[Damien Zammit]

0-13 are on rising edge (legacy)
14-N are active-low level triggered.

This allows for PIIX3 chipset to have working IDE,
if we patch hurd/acpi to ignore buggy irq 9 response.

---
 i386/i386at/ioapic.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/i386/i386at/ioapic.c b/i386/i386at/ioapic.c
index 5dd2de2e..d0724f76 100644
--- a/i386/i386at/ioapic.c
+++ b/i386/i386at/ioapic.c
@@ -393,10 +393,11 @@ ioapic_configure(void)
      */
     entry.both.dest = lapic->apic_id.r >> 24;
 
-    for (pin = 0; pin < 16; pin++) {
+    /* ISA legacy IRQs */
+    for (pin = 0; pin < 14; pin++) {
         gsi = pin;
 
-        /* ISA legacy IRQs */
+        /* Legacy interrupts are on rising edge */
         entry.both.trigger = IOAPIC_EDGE_TRIGGERED;
         entry.both.polarity = IOAPIC_ACTIVE_HIGH;
 
@@ -426,10 +427,11 @@ ioapic_configure(void)
         }
     }
 
-    for (pin = 16; pin < ngsis; pin++) {
+    /* 14,15 and PCI IRQs PIRQ A-H */
+    for (pin = 14; pin < ngsis; pin++) {
         gsi = pin;
 
-        /* PCI IRQs PIRQ A-H */
+        /* ACPI interrupts default to level-triggered active-low */
         entry.both.trigger = IOAPIC_LEVEL_TRIGGERED;
         entry.both.polarity = IOAPIC_ACTIVE_LOW;
 
-- 
2.45.2