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authorLaurent Vivier <laurent@vivier.eu>2022-04-06 22:15:22 +0200
committerGeert Uytterhoeven <geert@linux-m68k.org>2022-04-11 11:48:01 +0200
commitc92e7ef16400bf035e8b49c7dd091bfce4f99773 (patch)
treefd060d9d4c8c1bf248df52d859f6b8b53ab62688 /include/clocksource
parent3378c7f48f497b5ad93a43dcd4f8d406a2609562 (diff)
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>
Diffstat (limited to 'include/clocksource')
-rw-r--r--include/clocksource/timer-goldfish.h31
1 files changed, 31 insertions, 0 deletions
diff --git a/include/clocksource/timer-goldfish.h b/include/clocksource/timer-goldfish.h
new file mode 100644
index 000000000000..05a3a4f610d6
--- /dev/null
+++ b/include/clocksource/timer-goldfish.h
@@ -0,0 +1,31 @@
+/* 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 */