cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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i8253.c (839B)

      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * i8253.c  8253/PIT functions
      4 *
      5 */
      6#include <linux/clockchips.h>
      7#include <linux/i8253.h>
      8#include <linux/export.h>
      9#include <linux/smp.h>
     10#include <linux/irq.h>
     11
     12#include <asm/time.h>
     13
     14static irqreturn_t timer_interrupt(int irq, void *dev_id)
     15{
     16	i8253_clockevent.event_handler(&i8253_clockevent);
     17
     18	return IRQ_HANDLED;
     19}
     20
     21void __init setup_pit_timer(void)
     22{
     23	unsigned long flags = IRQF_NOBALANCING | IRQF_TIMER;
     24
     25	clockevent_i8253_init(true);
     26	if (request_irq(0, timer_interrupt, flags, "timer", NULL))
     27		pr_err("Failed to request irq 0 (timer)\n");
     28}
     29
     30static int __init init_pit_clocksource(void)
     31{
     32	if (num_possible_cpus() > 1 || /* PIT does not scale! */
     33	    !clockevent_state_periodic(&i8253_clockevent))
     34		return 0;
     35
     36	return clocksource_i8253_init();
     37}
     38arch_initcall(init_pit_clocksource);