cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

numachip.c (2350B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 *
      4 * Copyright (C) 2015 Numascale AS. All rights reserved.
      5 */
      6
      7#include <linux/clockchips.h>
      8
      9#include <asm/irq.h>
     10#include <asm/numachip/numachip.h>
     11#include <asm/numachip/numachip_csr.h>
     12
     13static DEFINE_PER_CPU(struct clock_event_device, numachip2_ced);
     14
     15static cycles_t numachip2_timer_read(struct clocksource *cs)
     16{
     17	return numachip2_read64_lcsr(NUMACHIP2_TIMER_NOW);
     18}
     19
     20static struct clocksource numachip2_clocksource = {
     21	.name            = "numachip2",
     22	.rating          = 295,
     23	.read            = numachip2_timer_read,
     24	.mask            = CLOCKSOURCE_MASK(64),
     25	.flags           = CLOCK_SOURCE_IS_CONTINUOUS,
     26	.mult            = 1,
     27	.shift           = 0,
     28};
     29
     30static int numachip2_set_next_event(unsigned long delta, struct clock_event_device *ced)
     31{
     32	numachip2_write64_lcsr(NUMACHIP2_TIMER_DEADLINE + numachip2_timer(),
     33		delta);
     34	return 0;
     35}
     36
     37static const struct clock_event_device numachip2_clockevent __initconst = {
     38	.name            = "numachip2",
     39	.rating          = 400,
     40	.set_next_event  = numachip2_set_next_event,
     41	.features        = CLOCK_EVT_FEAT_ONESHOT,
     42	.mult            = 1,
     43	.shift           = 0,
     44	.min_delta_ns    = 1250,
     45	.min_delta_ticks = 1250,
     46	.max_delta_ns    = LONG_MAX,
     47	.max_delta_ticks = LONG_MAX,
     48};
     49
     50static void numachip_timer_interrupt(void)
     51{
     52	struct clock_event_device *ced = this_cpu_ptr(&numachip2_ced);
     53
     54	ced->event_handler(ced);
     55}
     56
     57static __init void numachip_timer_each(struct work_struct *work)
     58{
     59	unsigned local_apicid = __this_cpu_read(x86_cpu_to_apicid) & 0xff;
     60	struct clock_event_device *ced = this_cpu_ptr(&numachip2_ced);
     61
     62	/* Setup IPI vector to local core and relative timing mode */
     63	numachip2_write64_lcsr(NUMACHIP2_TIMER_INT + numachip2_timer(),
     64		(3 << 22) | (X86_PLATFORM_IPI_VECTOR << 14) |
     65		(local_apicid << 6));
     66
     67	*ced = numachip2_clockevent;
     68	ced->cpumask = cpumask_of(smp_processor_id());
     69	clockevents_register_device(ced);
     70}
     71
     72static int __init numachip_timer_init(void)
     73{
     74	if (numachip_system != 2)
     75		return -ENODEV;
     76
     77	/* Reset timer */
     78	numachip2_write64_lcsr(NUMACHIP2_TIMER_RESET, 0);
     79	clocksource_register_hz(&numachip2_clocksource, NSEC_PER_SEC);
     80
     81	/* Setup per-cpu clockevents */
     82	x86_platform_ipi_callback = numachip_timer_interrupt;
     83	schedule_on_each_cpu(&numachip_timer_each);
     84
     85	return 0;
     86}
     87
     88arch_initcall(numachip_timer_init);