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6d671e1b85
Even without a PIC/PIT the legacy timer interrupt is required for HPET in legacy replacement mode. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: len.brown@intel.com Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20171222092243.382623763@infradead.org
107 lines
2.4 KiB
C
107 lines
2.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (c) 1991,1992,1995 Linus Torvalds
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* Copyright (c) 1994 Alan Modra
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* Copyright (c) 1995 Markus Kuhn
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* Copyright (c) 1996 Ingo Molnar
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* Copyright (c) 1998 Andrea Arcangeli
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* Copyright (c) 2002,2006 Vojtech Pavlik
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* Copyright (c) 2003 Andi Kleen
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*
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*/
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#include <linux/clockchips.h>
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#include <linux/interrupt.h>
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#include <linux/i8253.h>
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#include <linux/time.h>
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#include <linux/export.h>
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#include <asm/vsyscall.h>
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#include <asm/x86_init.h>
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#include <asm/i8259.h>
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#include <asm/timer.h>
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#include <asm/hpet.h>
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#include <asm/time.h>
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#ifdef CONFIG_X86_64
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__visible volatile unsigned long jiffies __cacheline_aligned = INITIAL_JIFFIES;
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#endif
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unsigned long profile_pc(struct pt_regs *regs)
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{
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unsigned long pc = instruction_pointer(regs);
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if (!user_mode(regs) && in_lock_functions(pc)) {
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#ifdef CONFIG_FRAME_POINTER
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return *(unsigned long *)(regs->bp + sizeof(long));
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#else
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unsigned long *sp =
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(unsigned long *)kernel_stack_pointer(regs);
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/*
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* Return address is either directly at stack pointer
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* or above a saved flags. Eflags has bits 22-31 zero,
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* kernel addresses don't.
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*/
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if (sp[0] >> 22)
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return sp[0];
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if (sp[1] >> 22)
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return sp[1];
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#endif
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}
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return pc;
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}
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EXPORT_SYMBOL(profile_pc);
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/*
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* Default timer interrupt handler for PIT/HPET
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*/
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static irqreturn_t timer_interrupt(int irq, void *dev_id)
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{
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global_clock_event->event_handler(global_clock_event);
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return IRQ_HANDLED;
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}
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static struct irqaction irq0 = {
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.handler = timer_interrupt,
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.flags = IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER,
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.name = "timer"
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};
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static void __init setup_default_timer_irq(void)
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{
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/*
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* Unconditionally register the legacy timer; even without legacy
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* PIC/PIT we need this for the HPET0 in legacy replacement mode.
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*/
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if (setup_irq(0, &irq0))
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pr_info("Failed to register legacy timer interrupt\n");
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}
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/* Default timer init function */
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void __init hpet_time_init(void)
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{
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if (!hpet_enable())
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setup_pit_timer();
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setup_default_timer_irq();
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}
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static __init void x86_late_time_init(void)
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{
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x86_init.timers.timer_init();
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/*
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* After PIT/HPET timers init, select and setup
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* the final interrupt mode for delivering IRQs.
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*/
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x86_init.irqs.intr_mode_init();
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tsc_init();
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}
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/*
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* Initialize TSC and delay the periodic timer init to
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* late x86_late_time_init() so ioremap works.
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*/
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void __init time_init(void)
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{
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late_time_init = x86_late_time_init;
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}
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