diff options
Diffstat (limited to 'arch/x86/kernel/time_32.c')
| -rw-r--r-- | arch/x86/kernel/time_32.c | 18 |
1 files changed, 3 insertions, 15 deletions
diff --git a/arch/x86/kernel/time_32.c b/arch/x86/kernel/time_32.c index 7a26bcf887f6..ec729cdcfa3d 100644 --- a/arch/x86/kernel/time_32.c +++ b/arch/x86/kernel/time_32.c @@ -78,21 +78,9 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id) global_clock_event->event_handler(global_clock_event); -#ifdef CONFIG_MCA - if (MCA_bus) { - /* The PS/2 uses level-triggered interrupts. You can't - turn them off, nor would you want to (any attempt to - enable edge-triggered interrupts usually gets intercepted by a - special hardware circuit). Hence we have to acknowledge - the timer interrupt. Through some incredibly stupid - design idea, the reset for IRQ 0 is done by setting the - high bit of the PPI port B (0x61). Note that some PS/2s, - notably the 55SX, work fine if this is removed. */ - - u8 irq_v = inb_p(0x61); /* read the current state */ - outb_p(irq_v | 0x80, 0x61); /* reset the IRQ */ - } -#endif + /* MCA bus quirk: Acknowledge irq0 by setting bit 7 in port 0x61 */ + if (MCA_bus) + outb_p(inb_p(0x61)| 0x80, 0x61); return IRQ_HANDLED; } |