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Diffstat (limited to 'arch/mips/sgi-ip30/ip30-timer.c')
-rw-r--r--arch/mips/sgi-ip30/ip30-timer.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/mips/sgi-ip30/ip30-timer.c b/arch/mips/sgi-ip30/ip30-timer.c
new file mode 100644
index 000000000000..d13e105478ae
--- /dev/null
+++ b/arch/mips/sgi-ip30/ip30-timer.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ip30-timer.c: Clocksource/clockevent support for the
+ * HEART chip in SGI Octane (IP30) systems.
+ *
+ * Copyright (C) 2004-2007 Stanislaw Skowronek <skylark@unaligned.org>
+ * Copyright (C) 2009 Johannes Dickgreber <tanzy@gmx.de>
+ * Copyright (C) 2011 Joshua Kinard <kumba@gentoo.org>
+ */
+
+#include <linux/clocksource.h>
+#include <linux/cpumask.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/sched_clock.h>
+
+#include <asm/time.h>
+#include <asm/cevt-r4k.h>
+#include <asm/sgi/heart.h>
+
+static u64 ip30_heart_counter_read(struct clocksource *cs)
+{
+ return heart_read(&heart_regs->count);
+}
+
+struct clocksource ip30_heart_clocksource = {
+ .name = "HEART",
+ .rating = 400,
+ .read = ip30_heart_counter_read,
+ .mask = CLOCKSOURCE_MASK(52),
+ .flags = (CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_VALID_FOR_HRES),
+};
+
+static u64 notrace ip30_heart_read_sched_clock(void)
+{
+ return heart_read(&heart_regs->count);
+}
+
+static void __init ip30_heart_clocksource_init(void)
+{
+ struct clocksource *cs = &ip30_heart_clocksource;
+
+ clocksource_register_hz(cs, HEART_CYCLES_PER_SEC);
+
+ sched_clock_register(ip30_heart_read_sched_clock, 52,
+ HEART_CYCLES_PER_SEC);
+}
+
+void __init plat_time_init(void)
+{
+ int irq = get_c0_compare_int();
+
+ cp0_timer_irq_installed = 1;
+ c0_compare_irqaction.percpu_dev_id = &mips_clockevent_device;
+ c0_compare_irqaction.flags &= ~IRQF_SHARED;
+ irq_set_handler(irq, handle_percpu_devid_irq);
+ irq_set_percpu_devid(irq);
+ setup_percpu_irq(irq, &c0_compare_irqaction);
+ enable_percpu_irq(irq, IRQ_TYPE_NONE);
+
+ ip30_heart_clocksource_init();
+}