void isr_apic_bottom(struct x86_exregs *regs)
{
struct lapic_info *apic = &cpu_apics[0];
#if 0
printf("%s: frame at %p, exregs=%p, frame_len=%u (size=%u)\n",
__func__, &apic, regs, (unsigned)x86_frame_len(regs),
(unsigned)sizeof(*regs));
#endif
/* figure out which interrupt this is from the ISRs. */
int vecnum;
bool vec_found = false;
for(int i=0; i <= apic->max_vector; i += 32) {
uint32_t isr_limb = mm_inl(apic->base_addr + APIC_ISR(i >> 5));
if(i == 0) isr_limb &= ~0xffffu;
if(isr_limb != 0) {
vecnum = i + ffsl(isr_limb) - 1;
vec_found = true;
break;
}
}
if(!vec_found) {
apic->num_spurious++;
ioapic_send_eoi(0); /* just in case. */
return;
}
#if 0
if(vecnum == 0x21) {
printf("i'm a keyboard, toot toot\n");
#define KBD_STATUS_REG 0x64
#define KBD_DATA_REG 0x60
#define KBD_STAT_OBF 0x01
for(;;) {
uint8_t st = inb(KBD_STATUS_REG);
if((st & KBD_STAT_OBF) == 0) break;
inb(KBD_DATA_REG); /* and throw it away */
}
} else {
printf("APIC interrupt vector %d\n", vecnum);
}
#endif
regs->reason = vecnum;
isr_irq_bottom(regs);
return;
#if 0
/* TODO: move this into an x86_print_exregs() function */
printf("exregs: reason=%#lx, es=%#lx, ds=%#lx, cs=%#lx, ss=%#lx\n"
"\tedi=%#lx, esi=%#lx, ebp=%#lx, __esp=%#lx\n"
"\tebx=%#lx, edx=%#lx, ecx=%#lx, eax=%#lx\n"
"\terror=%#lx, eip=%#lx, eflags=%#lx, esp=%#lx\n",
regs->reason, regs->es, regs->ds, regs->cs, regs->ss,
regs->edi, regs->esi, regs->ebp, regs->__esp,
regs->ebx, regs->edx, regs->ecx, regs->eax,
regs->error, regs->eip, regs->eflags, regs->esp);
#endif
}
static inline bool irq_in_kernel(const struct x86_exregs *frame) {
/* ring0 interrupts push a short stack frame. */
return x86_frame_len(frame) < sizeof(*frame);
}
