1 files changed, 355 insertions, 0 deletions
diff --git a/arch/sparc/kernel/time_32.c b/arch/sparc/kernel/time_32.c
new file mode 100644
index 000000000..08bbdc458
--- /dev/null
+++ b/arch/sparc/kernel/time_32.c
@@ -0,0 +1,355 @@
+// SPDX-License-Identifier: GPL-2.0
+/* linux/arch/sparc/kernel/time.c
+ *
+ * Copyright (C) 1995 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
+ *
+ * Chris Davis (cdavis@cois.on.ca) 03/27/1998
+ * Added support for the intersil on the sun4/4200
+ *
+ * Gleb Raiko (rajko@mech.math.msu.su) 08/18/1998
+ * Support for MicroSPARC-IIep, PCI CPU.
+ *
+ * This file handles the Sparc specific time handling details.
+ *
+ * 1997-09-10	Updated NTP code according to technical memorandum Jan '96
+ *		"A Kernel Model for Precision Timekeeping" by Dave Mills
+ */
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/rtc/m48t59.h>
+#include <linux/timex.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/profile.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#include <asm/mc146818rtc.h>
+#include <asm/oplib.h>
+#include <asm/timex.h>
+#include <asm/timer.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/idprom.h>
+#include <asm/page.h>
+#include <asm/pcic.h>
+#include <asm/irq_regs.h>
+#include <asm/setup.h>
+
+#include "kernel.h"
+#include "irq.h"
+
+static __cacheline_aligned_in_smp DEFINE_SEQLOCK(timer_cs_lock);
+static __volatile__ u64 timer_cs_internal_counter = 0;
+static char timer_cs_enabled = 0;
+
+static struct clock_event_device timer_ce;
+static char timer_ce_enabled = 0;
+
+#ifdef CONFIG_SMP
+DEFINE_PER_CPU(struct clock_event_device, sparc32_clockevent);
+#endif
+
+DEFINE_SPINLOCK(rtc_lock);
+EXPORT_SYMBOL(rtc_lock);
+
+unsigned long profile_pc(struct pt_regs *regs)
+{
+	extern char __copy_user_begin[], __copy_user_end[];
+	extern char __bzero_begin[], __bzero_end[];
+
+	unsigned long pc = regs->pc;
+
+	if (in_lock_functions(pc) ||
+	    (pc >= (unsigned long) __copy_user_begin &&
+	     pc < (unsigned long) __copy_user_end) ||
+	    (pc >= (unsigned long) __bzero_begin &&
+	     pc < (unsigned long) __bzero_end))
+		pc = regs->u_regs[UREG_RETPC];
+	return pc;
+}
+
+EXPORT_SYMBOL(profile_pc);
+
+volatile u32 __iomem *master_l10_counter;
+
+irqreturn_t notrace timer_interrupt(int dummy, void *dev_id)
+{
+	if (timer_cs_enabled) {
+		write_seqlock(&timer_cs_lock);
+		timer_cs_internal_counter++;
+		sparc_config.clear_clock_irq();
+		write_sequnlock(&timer_cs_lock);
+	} else {
+		sparc_config.clear_clock_irq();
+	}
+
+	if (timer_ce_enabled)
+		timer_ce.event_handler(&timer_ce);
+
+	return IRQ_HANDLED;
+}
+
+static int timer_ce_shutdown(struct clock_event_device *evt)
+{
+	timer_ce_enabled = 0;
+	smp_mb();
+	return 0;
+}
+
+static int timer_ce_set_periodic(struct clock_event_device *evt)
+{
+	timer_ce_enabled = 1;
+	smp_mb();
+	return 0;
+}
+
+static __init void setup_timer_ce(void)
+{
+	struct clock_event_device *ce = &timer_ce;
+
+	BUG_ON(smp_processor_id() != boot_cpu_id);
+
+	ce->name     = "timer_ce";
+	ce->rating   = 100;
+	ce->features = CLOCK_EVT_FEAT_PERIODIC;
+	ce->set_state_shutdown = timer_ce_shutdown;
+	ce->set_state_periodic = timer_ce_set_periodic;
+	ce->tick_resume = timer_ce_set_periodic;
+	ce->cpumask  = cpu_possible_mask;
+	ce->shift    = 32;
+	ce->mult     = div_sc(sparc_config.clock_rate, NSEC_PER_SEC,
+	                      ce->shift);
+	clockevents_register_device(ce);
+}
+
+static unsigned int sbus_cycles_offset(void)
+{
+	u32 val, offset;
+
+	val = sbus_readl(master_l10_counter);
+	offset = (val >> TIMER_VALUE_SHIFT) & TIMER_VALUE_MASK;
+
+	/* Limit hit? */
+	if (val & TIMER_LIMIT_BIT)
+		offset += sparc_config.cs_period;
+
+	return offset;
+}
+
+static u64 timer_cs_read(struct clocksource *cs)
+{
+	unsigned int seq, offset;
+	u64 cycles;
+
+	do {
+		seq = read_seqbegin(&timer_cs_lock);
+
+		cycles = timer_cs_internal_counter;
+		offset = sparc_config.get_cycles_offset();
+	} while (read_seqretry(&timer_cs_lock, seq));
+
+	/* Count absolute cycles */
+	cycles *= sparc_config.cs_period;
+	cycles += offset;
+
+	return cycles;
+}
+
+static struct clocksource timer_cs = {
+	.name	= "timer_cs",
+	.rating	= 100,
+	.read	= timer_cs_read,
+	.mask	= CLOCKSOURCE_MASK(64),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static __init int setup_timer_cs(void)
+{
+	timer_cs_enabled = 1;
+	return clocksource_register_hz(&timer_cs, sparc_config.clock_rate);
+}
+
+#ifdef CONFIG_SMP
+static int percpu_ce_shutdown(struct clock_event_device *evt)
+{
+	int cpu = cpumask_first(evt->cpumask);
+
+	sparc_config.load_profile_irq(cpu, 0);
+	return 0;
+}
+
+static int percpu_ce_set_periodic(struct clock_event_device *evt)
+{
+	int cpu = cpumask_first(evt->cpumask);
+
+	sparc_config.load_profile_irq(cpu, SBUS_CLOCK_RATE / HZ);
+	return 0;
+}
+
+static int percpu_ce_set_next_event(unsigned long delta,
+				    struct clock_event_device *evt)
+{
+	int cpu = cpumask_first(evt->cpumask);
+	unsigned int next = (unsigned int)delta;
+
+	sparc_config.load_profile_irq(cpu, next);
+	return 0;
+}
+
+void register_percpu_ce(int cpu)
+{
+	struct clock_event_device *ce = &per_cpu(sparc32_clockevent, cpu);
+	unsigned int features = CLOCK_EVT_FEAT_PERIODIC;
+
+	if (sparc_config.features & FEAT_L14_ONESHOT)
+		features |= CLOCK_EVT_FEAT_ONESHOT;
+
+	ce->name           = "percpu_ce";
+	ce->rating         = 200;
+	ce->features       = features;
+	ce->set_state_shutdown = percpu_ce_shutdown;
+	ce->set_state_periodic = percpu_ce_set_periodic;
+	ce->set_state_oneshot = percpu_ce_shutdown;
+	ce->set_next_event = percpu_ce_set_next_event;
+	ce->cpumask        = cpumask_of(cpu);
+	ce->shift          = 32;
+	ce->mult           = div_sc(sparc_config.clock_rate, NSEC_PER_SEC,
+	                            ce->shift);
+	ce->max_delta_ns   = clockevent_delta2ns(sparc_config.clock_rate, ce);
+	ce->max_delta_ticks = (unsigned long)sparc_config.clock_rate;
+	ce->min_delta_ns   = clockevent_delta2ns(100, ce);
+	ce->min_delta_ticks = 100;
+
+	clockevents_register_device(ce);
+}
+#endif
+
+static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
+
+	return readb(pdata->ioaddr + ofs);
+}
+
+static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
+
+	writeb(val, pdata->ioaddr + ofs);
+}
+
+static struct m48t59_plat_data m48t59_data = {
+	.read_byte = mostek_read_byte,
+	.write_byte = mostek_write_byte,
+};
+
+/* resource is set at runtime */
+static struct platform_device m48t59_rtc = {
+	.name		= "rtc-m48t59",
+	.id		= 0,
+	.num_resources	= 1,
+	.dev	= {
+		.platform_data = &m48t59_data,
+	},
+};
+
+static int clock_probe(struct platform_device *op)
+{
+	struct device_node *dp = op->dev.of_node;
+	const char *model = of_get_property(dp, "model", NULL);
+
+	if (!model)
+		return -ENODEV;
+
+	/* Only the primary RTC has an address property */
+	if (!of_property_present(dp, "address"))
+		return -ENODEV;
+
+	m48t59_rtc.resource = &op->resource[0];
+	if (!strcmp(model, "mk48t02")) {
+		/* Map the clock register io area read-only */
+		m48t59_data.ioaddr = of_ioremap(&op->resource[0], 0,
+						2048, "rtc-m48t59");
+		m48t59_data.type = M48T59RTC_TYPE_M48T02;
+	} else if (!strcmp(model, "mk48t08")) {
+		m48t59_data.ioaddr = of_ioremap(&op->resource[0], 0,
+						8192, "rtc-m48t59");
+		m48t59_data.type = M48T59RTC_TYPE_M48T08;
+	} else
+		return -ENODEV;
+
+	if (platform_device_register(&m48t59_rtc) < 0)
+		printk(KERN_ERR "Registering RTC device failed\n");
+
+	return 0;
+}
+
+static const struct of_device_id clock_match[] = {
+	{
+		.name = "eeprom",
+	},
+	{},
+};
+
+static struct platform_driver clock_driver = {
+	.probe		= clock_probe,
+	.driver = {
+		.name = "rtc",
+		.of_match_table = clock_match,
+	},
+};
+
+
+/* Probe for the mostek real time clock chip. */
+static int __init clock_init(void)
+{
+	return platform_driver_register(&clock_driver);
+}
+/* Must be after subsys_initcall() so that busses are probed.  Must
+ * be before device_initcall() because things like the RTC driver
+ * need to see the clock registers.
+ */
+fs_initcall(clock_init);
+
+static void __init sparc32_late_time_init(void)
+{
+	if (sparc_config.features & FEAT_L10_CLOCKEVENT)
+		setup_timer_ce();
+	if (sparc_config.features & FEAT_L10_CLOCKSOURCE)
+		setup_timer_cs();
+#ifdef CONFIG_SMP
+	register_percpu_ce(smp_processor_id());
+#endif
+}
+
+static void __init sbus_time_init(void)
+{
+	sparc_config.get_cycles_offset = sbus_cycles_offset;
+	sparc_config.init_timers();
+}
+
+void __init time_init(void)
+{
+	sparc_config.features = 0;
+	late_time_init = sparc32_late_time_init;
+
+	if (pcic_present())
+		pci_time_init();
+	else
+		sbus_time_init();
+}
+