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// 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/of_device.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_find_property(dp, "address", NULL))
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();
}