linux/include/clocksource/timer-goldfish.h
Laurent Vivier c92e7ef164 clocksource/drivers: Add a goldfish-timer clocksource
Add a clocksource based on the goldfish-rtc device.

Move the timer register definition to <clocksource/timer-goldfish.h>

This kernel implementation is based on the QEMU upstream implementation:

   https://git.qemu.org/?p=qemu.git;a=blob_plain;f=hw/rtc/goldfish_rtc.c

goldfish-timer is a high-precision signed 64-bit nanosecond timer.
It is part of the 'goldfish' virtual hardware platform used to run
some emulated Android systems under QEMU.
This timer only supports oneshot event.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20220406201523.243733-4-laurent@vivier.eu
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2022-04-11 11:48:01 +02:00

32 lines
1007 B
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* goldfish-timer clocksource
* Registers definition for the goldfish-timer device
*/
#ifndef _CLOCKSOURCE_TIMER_GOLDFISH_H
#define _CLOCKSOURCE_TIMER_GOLDFISH_H
/*
* TIMER_TIME_LOW get low bits of current time and update TIMER_TIME_HIGH
* TIMER_TIME_HIGH get high bits of time at last TIMER_TIME_LOW read
* TIMER_ALARM_LOW set low bits of alarm and activate it
* TIMER_ALARM_HIGH set high bits of next alarm
* TIMER_IRQ_ENABLED enable alarm interrupt
* TIMER_CLEAR_ALARM disarm an existing alarm
* TIMER_ALARM_STATUS alarm status (running or not)
* TIMER_CLEAR_INTERRUPT clear interrupt
*/
#define TIMER_TIME_LOW 0x00
#define TIMER_TIME_HIGH 0x04
#define TIMER_ALARM_LOW 0x08
#define TIMER_ALARM_HIGH 0x0c
#define TIMER_IRQ_ENABLED 0x10
#define TIMER_CLEAR_ALARM 0x14
#define TIMER_ALARM_STATUS 0x18
#define TIMER_CLEAR_INTERRUPT 0x1c
extern int goldfish_timer_init(int irq, void __iomem *base);
#endif /* _CLOCKSOURCE_TIMER_GOLDFISH_H */