Files
android/arch/ia64/sn/kernel/sn2/timer.c
T
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

62 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/ia64/sn/kernel/sn2/timer.c
*
* Copyright (C) 2003 Silicon Graphics, Inc.
* Copyright (C) 2003 Hewlett-Packard Co
* David Mosberger <davidm@hpl.hp.com>: updated for new timer-interpolation infrastructure
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/clocksource.h>
#include <asm/hw_irq.h>
#include <asm/timex.h>
#include <asm/sn/leds.h>
#include <asm/sn/shub_mmr.h>
#include <asm/sn/clksupport.h>
extern unsigned long sn_rtc_cycles_per_second;
static u64 read_sn2(struct clocksource *cs)
{
return (u64)readq(RTC_COUNTER_ADDR);
}
static struct clocksource clocksource_sn2 = {
.name = "sn2_rtc",
.rating = 450,
.read = read_sn2,
.mask = (1LL << 55) - 1,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
/*
* sn udelay uses the RTC instead of the ITC because the ITC is not
* synchronized across all CPUs, and the thread may migrate to another CPU
* if preemption is enabled.
*/
static void
ia64_sn_udelay (unsigned long usecs)
{
unsigned long start = rtc_time();
unsigned long end = start +
usecs * sn_rtc_cycles_per_second / 1000000;
while (time_before((unsigned long)rtc_time(), end))
cpu_relax();
}
void __init sn_timer_init(void)
{
clocksource_sn2.archdata.fsys_mmio = RTC_COUNTER_ADDR;
clocksource_register_hz(&clocksource_sn2, sn_rtc_cycles_per_second);
ia64_udelay = &ia64_sn_udelay;
}