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Release 4.16 drivers/clocksource/mips-gic-timer.c

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
 */
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/cpu.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/of_irq.h>
#include <linux/percpu.h>
#include <linux/smp.h>
#include <linux/time.h>
#include <asm/mips-cps.h>

static DEFINE_PER_CPU(struct clock_event_device, gic_clockevent_device);

static int gic_timer_irq;

static unsigned int gic_frequency;


static u64 notrace gic_read_count(void) { unsigned int hi, hi2, lo; if (mips_cm_is64) return read_gic_counter(); do { hi = read_gic_counter_32h(); lo = read_gic_counter_32l(); hi2 = read_gic_counter_32h(); } while (hi2 != hi); return (((u64) hi) << 32) + lo; }

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Paul Burton64100.00%1100.00%
Total64100.00%1100.00%


static int gic_next_event(unsigned long delta, struct clock_event_device *evt) { int cpu = cpumask_first(evt->cpumask); u64 cnt; int res; cnt = gic_read_count(); cnt += (u64)delta; if (cpu == raw_smp_processor_id()) { write_gic_vl_compare(cnt); } else { write_gic_vl_other(mips_cm_vp_id(cpu)); write_gic_vo_compare(cnt); } res = ((int)(gic_read_count() - cnt) >= 0) ? -ETIME : 0; return res; }

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Andrew Bresticker5960.82%133.33%
Matt Redfearn2828.87%133.33%
Paul Burton1010.31%133.33%
Total97100.00%3100.00%


static irqreturn_t gic_compare_interrupt(int irq, void *dev_id) { struct clock_event_device *cd = dev_id; write_gic_vl_compare(read_gic_vl_compare()); cd->event_handler(cd); return IRQ_HANDLED; }

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Andrew Bresticker3494.44%375.00%
Paul Burton25.56%125.00%
Total36100.00%4100.00%

struct irqaction gic_compare_irqaction = { .handler = gic_compare_interrupt, .percpu_dev_id = &gic_clockevent_device, .flags = IRQF_PERCPU | IRQF_TIMER, .name = "timer", };
static void gic_clockevent_cpu_init(unsigned int cpu, struct clock_event_device *cd) { cd->name = "MIPS GIC"; cd->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP; cd->rating = 350; cd->irq = gic_timer_irq; cd->cpumask = cpumask_of(cpu); cd->set_next_event = gic_next_event; clockevents_config_and_register(cd, gic_frequency, 0x300, 0x7fffffff); enable_percpu_irq(gic_timer_irq, IRQ_TYPE_NONE); }

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Andrew Bresticker7094.59%480.00%
Richard Cochran45.41%120.00%
Total74100.00%5100.00%


static void gic_clockevent_cpu_exit(struct clock_event_device *cd) { disable_percpu_irq(gic_timer_irq); }

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Andrew Bresticker16100.00%1100.00%
Total16100.00%1100.00%


static void gic_update_frequency(void *data) { unsigned long rate = (unsigned long)data; clockevents_update_freq(this_cpu_ptr(&gic_clockevent_device), rate); }

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Ezequiel García31100.00%1100.00%
Total31100.00%1100.00%


static int gic_starting_cpu(unsigned int cpu) { gic_clockevent_cpu_init(cpu, this_cpu_ptr(&gic_clockevent_device)); return 0; }

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Andrew Bresticker1875.00%150.00%
Richard Cochran625.00%150.00%
Total24100.00%2100.00%


static int gic_clk_notifier(struct notifier_block *nb, unsigned long action, void *data) { struct clk_notifier_data *cnd = data; if (action == POST_RATE_CHANGE) on_each_cpu(gic_update_frequency, (void *)cnd->new_rate, 1); return NOTIFY_OK; }

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Ezequiel García50100.00%1100.00%
Total50100.00%1100.00%


static int gic_dying_cpu(unsigned int cpu) { gic_clockevent_cpu_exit(this_cpu_ptr(&gic_clockevent_device)); return 0; }

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Richard Cochran2090.91%150.00%
Andrew Bresticker29.09%150.00%
Total22100.00%2100.00%

static struct notifier_block gic_clk_nb = { .notifier_call = gic_clk_notifier, };
static int gic_clockevent_init(void) { int ret; if (!gic_frequency) return -ENXIO; ret = setup_percpu_irq(gic_timer_irq, &gic_compare_irqaction); if (ret < 0) { pr_err("GIC timer IRQ %d setup failed: %d\n", gic_timer_irq, ret); return ret; } cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING, "clockevents/mips/gic/timer:starting", gic_starting_cpu, gic_dying_cpu); return 0; }

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Andrew Bresticker3046.88%233.33%
Ezequiel García1523.44%116.67%
Paul Burton1117.19%116.67%
Richard Cochran710.94%116.67%
Thomas Gleixner11.56%116.67%
Total64100.00%6100.00%


static u64 gic_hpt_read(struct clocksource *cs) { return gic_read_count(); }

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Steven J. Hill1493.33%266.67%
Thomas Gleixner16.67%133.33%
Total15100.00%3100.00%

static struct clocksource gic_clocksource = { .name = "GIC", .read = gic_hpt_read, .flags = CLOCK_SOURCE_IS_CONTINUOUS, .archdata = { .vdso_clock_mode = VDSO_CLOCK_GIC }, };
static int __init __gic_clocksource_init(void) { unsigned int count_width; int ret; /* Set clocksource mask. */ count_width = read_gic_config() & GIC_CONFIG_COUNTBITS; count_width >>= __ffs(GIC_CONFIG_COUNTBITS); count_width *= 4; count_width += 32; gic_clocksource.mask = CLOCKSOURCE_MASK(count_width); /* Calculate a somewhat reasonable rating value. */ gic_clocksource.rating = 200 + gic_frequency / 10000000; ret = clocksource_register_hz(&gic_clocksource, gic_frequency); if (ret < 0) pr_warn("GIC: Unable to register clocksource\n"); return ret; }

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Steven J. Hill3137.35%114.29%
Paul Burton2631.33%114.29%
Ezequiel García1518.07%114.29%
Andrew Bresticker67.23%228.57%
Daniel Lezcano44.82%114.29%
Felix Fietkau11.20%114.29%
Total83100.00%7100.00%


static int __init gic_clocksource_of_init(struct device_node *node) { struct clk *clk; int ret; if (!mips_gic_present() || !node->parent || !of_device_is_compatible(node->parent, "mti,gic")) { pr_warn("No DT definition for the mips gic driver\n"); return -ENXIO; } clk = of_clk_get(node, 0); if (!IS_ERR(clk)) { ret = clk_prepare_enable(clk); if (ret < 0) { pr_err("GIC failed to enable clock\n"); clk_put(clk); return ret; } gic_frequency = clk_get_rate(clk); } else if (of_property_read_u32(node, "clock-frequency", &gic_frequency)) { pr_err("GIC frequency not specified.\n"); return -EINVAL; } gic_timer_irq = irq_of_parse_and_map(node, 0); if (!gic_timer_irq) { pr_err("GIC timer IRQ not specified.\n"); return -EINVAL; } ret = __gic_clocksource_init(); if (ret) return ret; ret = gic_clockevent_init(); if (!ret && !IS_ERR(clk)) { if (clk_notifier_register(clk, &gic_clk_nb) < 0) pr_warn("GIC: Unable to register clock notifier\n"); } /* And finally start the counter */ clear_gic_config(GIC_CONFIG_COUNTSTOP); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Bresticker10750.71%220.00%
Ezequiel García5727.01%330.00%
Daniel Lezcano3215.17%110.00%
Christophe Jaillet73.32%110.00%
Paul Burton62.84%110.00%
Paul Gortmaker10.47%110.00%
Rafał Miłecki10.47%110.00%
Total211100.00%10100.00%

TIMER_OF_DECLARE(mips_gic_timer, "mti,gic-timer", gic_clocksource_of_init);

Overall Contributors

PersonTokensPropCommitsCommitProp
Andrew Bresticker42245.82%1034.48%
Ezequiel García18019.54%413.79%
Paul Burton12213.25%26.90%
Steven J. Hill737.93%26.90%
Daniel Lezcano374.02%26.90%
Richard Cochran374.02%13.45%
Matt Redfearn283.04%13.45%
Alex Smith101.09%13.45%
Christophe Jaillet70.76%13.45%
Thomas Gleixner20.22%26.90%
Paul Gortmaker10.11%13.45%
Felix Fietkau10.11%13.45%
Rafał Miłecki10.11%13.45%
Total921100.00%29100.00%
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