1 files changed, 71 insertions, 0 deletions
diff --git a/arch/mips/kernel/csrc-sb1250.c b/arch/mips/kernel/csrc-sb1250.c
new file mode 100644
index 000000000..fa2fa3e10
--- /dev/null
+++ b/arch/mips/kernel/csrc-sb1250.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2000, 2001 Broadcom Corporation
+ */
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+
+#include <asm/addrspace.h>
+#include <asm/io.h>
+#include <asm/time.h>
+
+#include <asm/sibyte/sb1250.h>
+#include <asm/sibyte/sb1250_regs.h>
+#include <asm/sibyte/sb1250_int.h>
+#include <asm/sibyte/sb1250_scd.h>
+
+#define SB1250_HPT_NUM		3
+#define SB1250_HPT_VALUE	M_SCD_TIMER_CNT /* max value */
+
+/*
+ * The HPT is free running from SB1250_HPT_VALUE down to 0 then starts over
+ * again.
+ */
+static inline u64 sb1250_hpt_get_cycles(void)
+{
+	unsigned int count;
+	void __iomem *addr;
+
+	addr = IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM, R_SCD_TIMER_CNT));
+	count = G_SCD_TIMER_CNT(__raw_readq(addr));
+
+	return SB1250_HPT_VALUE - count;
+}
+
+static u64 sb1250_hpt_read(struct clocksource *cs)
+{
+	return sb1250_hpt_get_cycles();
+}
+
+struct clocksource bcm1250_clocksource = {
+	.name	= "bcm1250-counter-3",
+	.rating = 200,
+	.read	= sb1250_hpt_read,
+	.mask	= CLOCKSOURCE_MASK(23),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static u64 notrace sb1250_read_sched_clock(void)
+{
+	return sb1250_hpt_get_cycles();
+}
+
+void __init sb1250_clocksource_init(void)
+{
+	struct clocksource *cs = &bcm1250_clocksource;
+
+	/* Setup hpt using timer #3 but do not enable irq for it */
+	__raw_writeq(0,
+		     IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
+						 R_SCD_TIMER_CFG)));
+	__raw_writeq(SB1250_HPT_VALUE,
+		     IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
+						 R_SCD_TIMER_INIT)));
+	__raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
+		     IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
+						 R_SCD_TIMER_CFG)));
+
+	clocksource_register_hz(cs, V_SCD_TIMER_FREQ);
+
+	sched_clock_register(sb1250_read_sched_clock, 23, V_SCD_TIMER_FREQ);
+}