ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/mips/generic/board-ranchu.c b/marvell/linux/arch/mips/generic/board-ranchu.c
new file mode 100644
index 0000000..a89aaad
--- /dev/null
+++ b/marvell/linux/arch/mips/generic/board-ranchu.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Support code for virtual Ranchu board for MIPS.
+ *
+ * Author: Miodrag Dinic <miodrag.dinic@mips.com>
+ */
+
+#include <linux/of_address.h>
+#include <linux/types.h>
+
+#include <asm/machine.h>
+#include <asm/mipsregs.h>
+#include <asm/time.h>
+
+#define GOLDFISH_TIMER_LOW 0x00
+#define GOLDFISH_TIMER_HIGH 0x04
+
+static __init u64 read_rtc_time(void __iomem *base)
+{
+ u32 time_low;
+ u32 time_high;
+
+ /*
+ * Reading the low address latches the high value
+ * as well so there is no fear that we may read
+ * inaccurate high value.
+ */
+ time_low = readl(base + GOLDFISH_TIMER_LOW);
+ time_high = readl(base + GOLDFISH_TIMER_HIGH);
+
+ return ((u64)time_high << 32) | time_low;
+}
+
+static __init unsigned int ranchu_measure_hpt_freq(void)
+{
+ u64 rtc_start, rtc_current, rtc_delta;
+ unsigned int start, count;
+ struct device_node *np;
+ void __iomem *rtc_base;
+
+ np = of_find_compatible_node(NULL, NULL, "google,goldfish-rtc");
+ if (!np)
+ panic("%s(): Failed to find 'google,goldfish-rtc' dt node!",
+ __func__);
+
+ rtc_base = of_iomap(np, 0);
+ if (!rtc_base)
+ panic("%s(): Failed to ioremap Goldfish RTC base!", __func__);
+
+ /*
+ * Poll the nanosecond resolution RTC for one
+ * second to calibrate the CPU frequency.
+ */
+ rtc_start = read_rtc_time(rtc_base);
+ start = read_c0_count();
+
+ do {
+ rtc_current = read_rtc_time(rtc_base);
+ rtc_delta = rtc_current - rtc_start;
+ } while (rtc_delta < NSEC_PER_SEC);
+
+ count = read_c0_count() - start;
+
+ /*
+ * Make sure the frequency will be a round number.
+ * Without this correction, the returned value may vary
+ * between subsequent emulation executions.
+ *
+ * TODO: Set this value using device tree.
+ */
+ count += 5000;
+ count -= count % 10000;
+
+ iounmap(rtc_base);
+
+ return count;
+}
+
+static const struct of_device_id ranchu_of_match[] __initconst = {
+ {
+ .compatible = "mti,ranchu",
+ },
+ {}
+};
+
+MIPS_MACHINE(ranchu) = {
+ .matches = ranchu_of_match,
+ .measure_hpt_freq = ranchu_measure_hpt_freq,
+};