kernel_optimize_test/arch/mips/sgi-ip27/ip27-timer.c
Nicolai Stange e4db9253d6 MIPS: clockevent drivers: Set ->min_delta_ticks and ->max_delta_ticks
In preparation for making the clockevents core NTP correction aware,
all clockevent device drivers must set ->min_delta_ticks and
->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a
clockevent device's rate is going to change dynamically and thus, the
ratio of ns to ticks ceases to stay invariant.

Make the MIPS arch's clockevent drivers initialize these fields properly.

This patch alone doesn't introduce any change in functionality as the
clockevents core still looks exclusively at the (untouched) ->min_delta_ns
and ->max_delta_ns. As soon as this has changed, a followup patch will
purge the initialization of ->min_delta_ns and ->max_delta_ns from these
drivers.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Keguang Zhang <keguang.zhang@gmail.com>
Cc: John Crispin <john@phrozen.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2017-04-14 13:11:16 -07:00

238 lines
5.7 KiB
C

/*
* Copytight (C) 1999, 2000, 05, 06 Ralf Baechle (ralf@linux-mips.org)
* Copytight (C) 1999, 2000 Silicon Graphics, Inc.
*/
#include <linux/bcd.h>
#include <linux/clockchips.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sched_clock.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/param.h>
#include <linux/smp.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/mm.h>
#include <linux/platform_device.h>
#include <asm/time.h>
#include <asm/pgtable.h>
#include <asm/sgialib.h>
#include <asm/sn/ioc3.h>
#include <asm/sn/klconfig.h>
#include <asm/sn/arch.h>
#include <asm/sn/addrs.h>
#include <asm/sn/sn_private.h>
#include <asm/sn/sn0/ip27.h>
#include <asm/sn/sn0/hub.h>
#define TICK_SIZE (tick_nsec / 1000)
/* Includes for ioc3_init(). */
#include <asm/sn/types.h>
#include <asm/sn/sn0/addrs.h>
#include <asm/sn/sn0/hubni.h>
#include <asm/sn/sn0/hubio.h>
#include <asm/pci/bridge.h>
static void enable_rt_irq(struct irq_data *d)
{
}
static void disable_rt_irq(struct irq_data *d)
{
}
static struct irq_chip rt_irq_type = {
.name = "SN HUB RT timer",
.irq_mask = disable_rt_irq,
.irq_unmask = enable_rt_irq,
};
static int rt_next_event(unsigned long delta, struct clock_event_device *evt)
{
unsigned int cpu = smp_processor_id();
int slice = cputoslice(cpu);
unsigned long cnt;
cnt = LOCAL_HUB_L(PI_RT_COUNT);
cnt += delta;
LOCAL_HUB_S(PI_RT_COMPARE_A + PI_COUNT_OFFSET * slice, cnt);
return LOCAL_HUB_L(PI_RT_COUNT) >= cnt ? -ETIME : 0;
}
unsigned int rt_timer_irq;
static DEFINE_PER_CPU(struct clock_event_device, hub_rt_clockevent);
static DEFINE_PER_CPU(char [11], hub_rt_name);
static irqreturn_t hub_rt_counter_handler(int irq, void *dev_id)
{
unsigned int cpu = smp_processor_id();
struct clock_event_device *cd = &per_cpu(hub_rt_clockevent, cpu);
int slice = cputoslice(cpu);
/*
* Ack
*/
LOCAL_HUB_S(PI_RT_PEND_A + PI_COUNT_OFFSET * slice, 0);
cd->event_handler(cd);
return IRQ_HANDLED;
}
struct irqaction hub_rt_irqaction = {
.handler = hub_rt_counter_handler,
.flags = IRQF_PERCPU | IRQF_TIMER,
.name = "hub-rt",
};
/*
* This is a hack; we really need to figure these values out dynamically
*
* Since 800 ns works very well with various HUB frequencies, such as
* 360, 380, 390 and 400 MHZ, we use 800 ns rtc cycle time.
*
* Ralf: which clock rate is used to feed the counter?
*/
#define NSEC_PER_CYCLE 800
#define CYCLES_PER_SEC (NSEC_PER_SEC / NSEC_PER_CYCLE)
void hub_rt_clock_event_init(void)
{
unsigned int cpu = smp_processor_id();
struct clock_event_device *cd = &per_cpu(hub_rt_clockevent, cpu);
unsigned char *name = per_cpu(hub_rt_name, cpu);
int irq = rt_timer_irq;
sprintf(name, "hub-rt %d", cpu);
cd->name = name;
cd->features = CLOCK_EVT_FEAT_ONESHOT;
clockevent_set_clock(cd, CYCLES_PER_SEC);
cd->max_delta_ns = clockevent_delta2ns(0xfffffffffffff, cd);
cd->max_delta_ticks = 0xfffffffffffff;
cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
cd->min_delta_ticks = 0x300;
cd->rating = 200;
cd->irq = irq;
cd->cpumask = cpumask_of(cpu);
cd->set_next_event = rt_next_event;
clockevents_register_device(cd);
}
static void __init hub_rt_clock_event_global_init(void)
{
int irq;
do {
smp_wmb();
irq = rt_timer_irq;
if (irq)
break;
irq = allocate_irqno();
if (irq < 0)
panic("Allocation of irq number for timer failed");
} while (xchg(&rt_timer_irq, irq));
irq_set_chip_and_handler(irq, &rt_irq_type, handle_percpu_irq);
setup_irq(irq, &hub_rt_irqaction);
}
static u64 hub_rt_read(struct clocksource *cs)
{
return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
}
struct clocksource hub_rt_clocksource = {
.name = "HUB-RT",
.rating = 200,
.read = hub_rt_read,
.mask = CLOCKSOURCE_MASK(52),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static u64 notrace hub_rt_read_sched_clock(void)
{
return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
}
static void __init hub_rt_clocksource_init(void)
{
struct clocksource *cs = &hub_rt_clocksource;
clocksource_register_hz(cs, CYCLES_PER_SEC);
sched_clock_register(hub_rt_read_sched_clock, 52, CYCLES_PER_SEC);
}
void __init plat_time_init(void)
{
hub_rt_clocksource_init();
hub_rt_clock_event_global_init();
hub_rt_clock_event_init();
}
void cpu_time_init(void)
{
lboard_t *board;
klcpu_t *cpu;
int cpuid;
/* Don't use ARCS. ARCS is fragile. Klconfig is simple and sane. */
board = find_lboard(KL_CONFIG_INFO(get_nasid()), KLTYPE_IP27);
if (!board)
panic("Can't find board info for myself.");
cpuid = LOCAL_HUB_L(PI_CPU_NUM) ? IP27_CPU0_INDEX : IP27_CPU1_INDEX;
cpu = (klcpu_t *) KLCF_COMP(board, cpuid);
if (!cpu)
panic("No information about myself?");
printk("CPU %d clock is %dMHz.\n", smp_processor_id(), cpu->cpu_speed);
set_c0_status(SRB_TIMOCLK);
}
void hub_rtc_init(cnodeid_t cnode)
{
/*
* We only need to initialize the current node.
* If this is not the current node then it is a cpuless
* node and timeouts will not happen there.
*/
if (get_compact_nodeid() == cnode) {
LOCAL_HUB_S(PI_RT_EN_A, 1);
LOCAL_HUB_S(PI_RT_EN_B, 1);
LOCAL_HUB_S(PI_PROF_EN_A, 0);
LOCAL_HUB_S(PI_PROF_EN_B, 0);
LOCAL_HUB_S(PI_RT_COUNT, 0);
LOCAL_HUB_S(PI_RT_PEND_A, 0);
LOCAL_HUB_S(PI_RT_PEND_B, 0);
}
}
static int __init sgi_ip27_rtc_devinit(void)
{
struct resource res;
memset(&res, 0, sizeof(res));
res.start = XPHYSADDR(KL_CONFIG_CH_CONS_INFO(master_nasid)->memory_base +
IOC3_BYTEBUS_DEV0);
res.end = res.start + 32767;
res.flags = IORESOURCE_MEM;
return IS_ERR(platform_device_register_simple("rtc-m48t35", -1,
&res, 1));
}
/*
* kludge make this a device_initcall after ioc3 resource conflicts
* are resolved
*/
late_initcall(sgi_ip27_rtc_devinit);