clocksource: apb: Share APB timer code with other platforms

The APB timers are an IP block from Synopsys (DesignWare APB timers)
and are also found in other systems including ARM SoC's.  This patch
adds functions for creating clock_event_devices and clocksources from
APB timers but does not do the resource allocation.  This is handled
in a higher layer to allow the timers to be created from multiple
methods such as platform_devices.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/include/linux/dw_apb_timer.h b/include/linux/dw_apb_timer.h
new file mode 100644
index 00000000000..49638ea3b77
--- /dev/null
+++ b/include/linux/dw_apb_timer.h
@@ -0,0 +1,56 @@
+/*
+ * (C) Copyright 2009 Intel Corporation
+ * Author: Jacob Pan (jacob.jun.pan@intel.com)
+ *
+ * Shared with ARM platforms, Jamie Iles, Picochip 2011
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Support for the Synopsys DesignWare APB Timers.
+ */
+#ifndef __DW_APB_TIMER_H__
+#define __DW_APB_TIMER_H__
+
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+
+#define APBTMRS_REG_SIZE       0x14
+
+struct dw_apb_timer {
+	void __iomem				*base;
+	unsigned long				freq;
+	int					irq;
+};
+
+struct dw_apb_clock_event_device {
+	struct clock_event_device		ced;
+	struct dw_apb_timer			timer;
+	struct irqaction			irqaction;
+	void					(*eoi)(struct dw_apb_timer *);
+};
+
+struct dw_apb_clocksource {
+	struct dw_apb_timer			timer;
+	struct clocksource			cs;
+};
+
+void dw_apb_clockevent_register(struct dw_apb_clock_event_device *dw_ced);
+void dw_apb_clockevent_pause(struct dw_apb_clock_event_device *dw_ced);
+void dw_apb_clockevent_resume(struct dw_apb_clock_event_device *dw_ced);
+void dw_apb_clockevent_stop(struct dw_apb_clock_event_device *dw_ced);
+
+struct dw_apb_clock_event_device *
+dw_apb_clockevent_init(int cpu, const char *name, unsigned rating,
+		       void __iomem *base, int irq, unsigned long freq);
+struct dw_apb_clocksource *
+dw_apb_clocksource_init(unsigned rating, char *name, void __iomem *base,
+			unsigned long freq);
+void dw_apb_clocksource_register(struct dw_apb_clocksource *dw_cs);
+void dw_apb_clocksource_start(struct dw_apb_clocksource *dw_cs);
+cycle_t dw_apb_clocksource_read(struct dw_apb_clocksource *dw_cs);
+void dw_apb_clocksource_unregister(struct dw_apb_clocksource *dw_cs);
+
+#endif /* __DW_APB_TIMER_H__ */