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-rw-r--r--arch/riscv/kernel/time.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/riscv/kernel/time.c b/arch/riscv/kernel/time.c
new file mode 100644
index 000000000000..2463fcca719e
--- /dev/null
+++ b/arch/riscv/kernel/time.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+
+#ifdef CONFIG_RISCV_TIMER
+#include <linux/timer_riscv.h>
+#endif
+
+#include <asm/sbi.h>
+
+unsigned long riscv_timebase;
+
+DECLARE_PER_CPU(struct clock_event_device, riscv_clock_event);
+
+void riscv_timer_interrupt(void)
+{
+#ifdef CONFIG_RISCV_TIMER
+ /*
+ * FIXME: This needs to be cleaned up along with the rest of the IRQ
+ * handling cleanup. See irq.c for more details.
+ */
+ struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event);
+
+ evdev->event_handler(evdev);
+#endif
+}
+
+void __init init_clockevent(void)
+{
+ timer_probe();
+ csr_set(sie, SIE_STIE);
+}
+
+void __init time_init(void)
+{
+ struct device_node *cpu;
+ u32 prop;
+
+ cpu = of_find_node_by_path("/cpus");
+ if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
+ panic(KERN_WARNING "RISC-V system with no 'timebase-frequency' in DTS\n");
+ riscv_timebase = prop;
+
+ lpj_fine = riscv_timebase / HZ;
+
+ init_clockevent();
+}