1 files changed, 138 insertions, 0 deletions
diff --git a/arch/mips/kernel/cevt-sb1250.c b/arch/mips/kernel/cevt-sb1250.c
new file mode 100644
index 000000000..0451273fa
--- /dev/null
+++ b/arch/mips/kernel/cevt-sb1250.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2000, 2001 Broadcom Corporation
+ */
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/percpu.h>
+#include <linux/smp.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 IMR_IP2_VAL	K_INT_MAP_I0
+#define IMR_IP3_VAL	K_INT_MAP_I1
+#define IMR_IP4_VAL	K_INT_MAP_I2
+
+/*
+ * The general purpose timer ticks at 1MHz independent if
+ * the rest of the system
+ */
+
+static int sibyte_shutdown(struct clock_event_device *evt)
+{
+	void __iomem *cfg;
+
+	cfg = IOADDR(A_SCD_TIMER_REGISTER(smp_processor_id(), R_SCD_TIMER_CFG));
+
+	/* Stop the timer until we actually program a shot */
+	__raw_writeq(0, cfg);
+
+	return 0;
+}
+
+static int sibyte_set_periodic(struct clock_event_device *evt)
+{
+	unsigned int cpu = smp_processor_id();
+	void __iomem *cfg, *init;
+
+	cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
+	init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT));
+
+	__raw_writeq(0, cfg);
+	__raw_writeq((V_SCD_TIMER_FREQ / HZ) - 1, init);
+	__raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS, cfg);
+
+	return 0;
+}
+
+static int sibyte_next_event(unsigned long delta, struct clock_event_device *cd)
+{
+	unsigned int cpu = smp_processor_id();
+	void __iomem *cfg, *init;
+
+	cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
+	init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT));
+
+	__raw_writeq(0, cfg);
+	__raw_writeq(delta - 1, init);
+	__raw_writeq(M_SCD_TIMER_ENABLE, cfg);
+
+	return 0;
+}
+
+static irqreturn_t sibyte_counter_handler(int irq, void *dev_id)
+{
+	unsigned int cpu = smp_processor_id();
+	struct clock_event_device *cd = dev_id;
+	void __iomem *cfg;
+	unsigned long tmode;
+
+	if (clockevent_state_periodic(cd))
+		tmode = M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS;
+	else
+		tmode = 0;
+
+	/* ACK interrupt */
+	cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
+	____raw_writeq(tmode, cfg);
+
+	cd->event_handler(cd);
+
+	return IRQ_HANDLED;
+}
+
+static DEFINE_PER_CPU(struct clock_event_device, sibyte_hpt_clockevent);
+static DEFINE_PER_CPU(char [18], sibyte_hpt_name);
+
+void sb1250_clockevent_init(void)
+{
+	unsigned int cpu = smp_processor_id();
+	unsigned int irq = K_INT_TIMER_0 + cpu;
+	struct clock_event_device *cd = &per_cpu(sibyte_hpt_clockevent, cpu);
+	unsigned char *name = per_cpu(sibyte_hpt_name, cpu);
+	unsigned long flags = IRQF_PERCPU | IRQF_TIMER;
+
+	/* Only have 4 general purpose timers, and we use last one as hpt */
+	BUG_ON(cpu > 2);
+
+	sprintf(name, "sb1250-counter-%d", cpu);
+	cd->name		= name;
+	cd->features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT;
+	clockevent_set_clock(cd, V_SCD_TIMER_FREQ);
+	cd->max_delta_ns	= clockevent_delta2ns(0x7fffff, cd);
+	cd->max_delta_ticks	= 0x7fffff;
+	cd->min_delta_ns	= clockevent_delta2ns(2, cd);
+	cd->min_delta_ticks	= 2;
+	cd->rating		= 200;
+	cd->irq			= irq;
+	cd->cpumask		= cpumask_of(cpu);
+	cd->set_next_event	= sibyte_next_event;
+	cd->set_state_shutdown	= sibyte_shutdown;
+	cd->set_state_periodic	= sibyte_set_periodic;
+	cd->set_state_oneshot	= sibyte_shutdown;
+	clockevents_register_device(cd);
+
+	sb1250_mask_irq(cpu, irq);
+
+	/*
+	 * Map the timer interrupt to IP[4] of this cpu
+	 */
+	__raw_writeq(IMR_IP4_VAL,
+		     IOADDR(A_IMR_REGISTER(cpu, R_IMR_INTERRUPT_MAP_BASE) +
+			    (irq << 3)));
+
+	sb1250_unmask_irq(cpu, irq);
+
+	irq_set_affinity(irq, cpumask_of(cpu));
+	if (request_irq(irq, sibyte_counter_handler, flags, name, cd))
+		pr_err("Failed to request irq %d (%s)\n", irq, name);
+}