1048 lines
24 KiB
C
1048 lines
24 KiB
C
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// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Intel & MS High Precision Event Timer Implementation.
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*
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* Copyright (C) 2003 Intel Corporation
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* Venki Pallipadi
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* (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
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* Bob Picco <robert.picco@hp.com>
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*/
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#include <linux/interrupt.h>
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#include <linux/kernel.h>
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#include <linux/types.h>
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#include <linux/miscdevice.h>
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#include <linux/major.h>
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#include <linux/ioport.h>
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#include <linux/fcntl.h>
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#include <linux/init.h>
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#include <linux/io-64-nonatomic-lo-hi.h>
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#include <linux/poll.h>
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#include <linux/mm.h>
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#include <linux/proc_fs.h>
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#include <linux/spinlock.h>
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#include <linux/sysctl.h>
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#include <linux/wait.h>
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#include <linux/sched/signal.h>
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#include <linux/bcd.h>
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#include <linux/seq_file.h>
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#include <linux/bitops.h>
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#include <linux/compat.h>
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#include <linux/clocksource.h>
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#include <linux/uaccess.h>
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#include <linux/slab.h>
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#include <linux/io.h>
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#include <linux/acpi.h>
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#include <linux/hpet.h>
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#include <asm/current.h>
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#include <asm/irq.h>
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#include <asm/div64.h>
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/*
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* The High Precision Event Timer driver.
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* This driver is closely modelled after the rtc.c driver.
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* See HPET spec revision 1.
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*/
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#define HPET_USER_FREQ (64)
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#define HPET_DRIFT (500)
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#define HPET_RANGE_SIZE 1024 /* from HPET spec */
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/* WARNING -- don't get confused. These macros are never used
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* to write the (single) counter, and rarely to read it.
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* They're badly named; to fix, someday.
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*/
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#if BITS_PER_LONG == 64
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#define write_counter(V, MC) writeq(V, MC)
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#define read_counter(MC) readq(MC)
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#else
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#define write_counter(V, MC) writel(V, MC)
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#define read_counter(MC) readl(MC)
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#endif
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static DEFINE_MUTEX(hpet_mutex); /* replaces BKL */
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static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
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/* This clocksource driver currently only works on ia64 */
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#ifdef CONFIG_IA64
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static void __iomem *hpet_mctr;
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static u64 read_hpet(struct clocksource *cs)
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{
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return (u64)read_counter((void __iomem *)hpet_mctr);
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}
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static struct clocksource clocksource_hpet = {
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.name = "hpet",
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.rating = 250,
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.read = read_hpet,
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.mask = CLOCKSOURCE_MASK(64),
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.flags = CLOCK_SOURCE_IS_CONTINUOUS,
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};
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static struct clocksource *hpet_clocksource;
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#endif
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/* A lock for concurrent access by app and isr hpet activity. */
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static DEFINE_SPINLOCK(hpet_lock);
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#define HPET_DEV_NAME (7)
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struct hpet_dev {
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struct hpets *hd_hpets;
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struct hpet __iomem *hd_hpet;
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struct hpet_timer __iomem *hd_timer;
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unsigned long hd_ireqfreq;
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unsigned long hd_irqdata;
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wait_queue_head_t hd_waitqueue;
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struct fasync_struct *hd_async_queue;
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unsigned int hd_flags;
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unsigned int hd_irq;
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unsigned int hd_hdwirq;
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char hd_name[HPET_DEV_NAME];
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};
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struct hpets {
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struct hpets *hp_next;
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struct hpet __iomem *hp_hpet;
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unsigned long hp_hpet_phys;
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struct clocksource *hp_clocksource;
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unsigned long long hp_tick_freq;
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unsigned long hp_delta;
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unsigned int hp_ntimer;
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unsigned int hp_which;
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struct hpet_dev hp_dev[];
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};
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static struct hpets *hpets;
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#define HPET_OPEN 0x0001
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#define HPET_IE 0x0002 /* interrupt enabled */
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#define HPET_PERIODIC 0x0004
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#define HPET_SHARED_IRQ 0x0008
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static irqreturn_t hpet_interrupt(int irq, void *data)
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{
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struct hpet_dev *devp;
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unsigned long isr;
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devp = data;
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isr = 1 << (devp - devp->hd_hpets->hp_dev);
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if ((devp->hd_flags & HPET_SHARED_IRQ) &&
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!(isr & readl(&devp->hd_hpet->hpet_isr)))
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return IRQ_NONE;
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spin_lock(&hpet_lock);
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devp->hd_irqdata++;
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/*
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* For non-periodic timers, increment the accumulator.
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* This has the effect of treating non-periodic like periodic.
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*/
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if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
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unsigned long t, mc, base, k;
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struct hpet __iomem *hpet = devp->hd_hpet;
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struct hpets *hpetp = devp->hd_hpets;
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t = devp->hd_ireqfreq;
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read_counter(&devp->hd_timer->hpet_compare);
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mc = read_counter(&hpet->hpet_mc);
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/* The time for the next interrupt would logically be t + m,
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* however, if we are very unlucky and the interrupt is delayed
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* for longer than t then we will completely miss the next
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* interrupt if we set t + m and an application will hang.
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* Therefore we need to make a more complex computation assuming
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* that there exists a k for which the following is true:
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* k * t + base < mc + delta
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* (k + 1) * t + base > mc + delta
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* where t is the interval in hpet ticks for the given freq,
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* base is the theoretical start value 0 < base < t,
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* mc is the main counter value at the time of the interrupt,
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* delta is the time it takes to write the a value to the
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* comparator.
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* k may then be computed as (mc - base + delta) / t .
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*/
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base = mc % t;
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k = (mc - base + hpetp->hp_delta) / t;
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write_counter(t * (k + 1) + base,
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&devp->hd_timer->hpet_compare);
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}
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if (devp->hd_flags & HPET_SHARED_IRQ)
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writel(isr, &devp->hd_hpet->hpet_isr);
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spin_unlock(&hpet_lock);
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wake_up_interruptible(&devp->hd_waitqueue);
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kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
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return IRQ_HANDLED;
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}
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static void hpet_timer_set_irq(struct hpet_dev *devp)
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{
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unsigned long v;
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int irq, gsi;
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struct hpet_timer __iomem *timer;
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spin_lock_irq(&hpet_lock);
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if (devp->hd_hdwirq) {
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spin_unlock_irq(&hpet_lock);
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return;
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}
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timer = devp->hd_timer;
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/* we prefer level triggered mode */
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v = readl(&timer->hpet_config);
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if (!(v & Tn_INT_TYPE_CNF_MASK)) {
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v |= Tn_INT_TYPE_CNF_MASK;
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writel(v, &timer->hpet_config);
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}
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spin_unlock_irq(&hpet_lock);
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v = (readq(&timer->hpet_config) & Tn_INT_ROUTE_CAP_MASK) >>
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Tn_INT_ROUTE_CAP_SHIFT;
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/*
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* In PIC mode, skip IRQ0-4, IRQ6-9, IRQ12-15 which is always used by
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* legacy device. In IO APIC mode, we skip all the legacy IRQS.
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*/
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if (acpi_irq_model == ACPI_IRQ_MODEL_PIC)
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v &= ~0xf3df;
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else
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v &= ~0xffff;
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for_each_set_bit(irq, &v, HPET_MAX_IRQ) {
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if (irq >= nr_irqs) {
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irq = HPET_MAX_IRQ;
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break;
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}
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gsi = acpi_register_gsi(NULL, irq, ACPI_LEVEL_SENSITIVE,
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ACPI_ACTIVE_LOW);
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if (gsi > 0)
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break;
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/* FIXME: Setup interrupt source table */
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}
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if (irq < HPET_MAX_IRQ) {
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spin_lock_irq(&hpet_lock);
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v = readl(&timer->hpet_config);
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v |= irq << Tn_INT_ROUTE_CNF_SHIFT;
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writel(v, &timer->hpet_config);
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devp->hd_hdwirq = gsi;
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spin_unlock_irq(&hpet_lock);
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}
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return;
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}
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static int hpet_open(struct inode *inode, struct file *file)
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{
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struct hpet_dev *devp;
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struct hpets *hpetp;
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int i;
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if (file->f_mode & FMODE_WRITE)
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return -EINVAL;
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mutex_lock(&hpet_mutex);
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spin_lock_irq(&hpet_lock);
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for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
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for (i = 0; i < hpetp->hp_ntimer; i++)
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if (hpetp->hp_dev[i].hd_flags & HPET_OPEN) {
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continue;
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} else {
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devp = &hpetp->hp_dev[i];
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break;
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}
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if (!devp) {
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spin_unlock_irq(&hpet_lock);
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mutex_unlock(&hpet_mutex);
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return -EBUSY;
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}
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file->private_data = devp;
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devp->hd_irqdata = 0;
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devp->hd_flags |= HPET_OPEN;
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spin_unlock_irq(&hpet_lock);
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mutex_unlock(&hpet_mutex);
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hpet_timer_set_irq(devp);
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return 0;
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}
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static ssize_t
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hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
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{
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DECLARE_WAITQUEUE(wait, current);
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unsigned long data;
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ssize_t retval;
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struct hpet_dev *devp;
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devp = file->private_data;
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if (!devp->hd_ireqfreq)
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return -EIO;
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if (count < sizeof(unsigned long))
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return -EINVAL;
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add_wait_queue(&devp->hd_waitqueue, &wait);
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for ( ; ; ) {
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set_current_state(TASK_INTERRUPTIBLE);
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spin_lock_irq(&hpet_lock);
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data = devp->hd_irqdata;
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devp->hd_irqdata = 0;
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spin_unlock_irq(&hpet_lock);
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if (data) {
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break;
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} else if (file->f_flags & O_NONBLOCK) {
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retval = -EAGAIN;
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goto out;
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} else if (signal_pending(current)) {
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retval = -ERESTARTSYS;
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goto out;
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}
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schedule();
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}
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retval = put_user(data, (unsigned long __user *)buf);
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if (!retval)
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retval = sizeof(unsigned long);
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out:
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__set_current_state(TASK_RUNNING);
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remove_wait_queue(&devp->hd_waitqueue, &wait);
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return retval;
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}
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static __poll_t hpet_poll(struct file *file, poll_table * wait)
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{
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unsigned long v;
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struct hpet_dev *devp;
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devp = file->private_data;
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if (!devp->hd_ireqfreq)
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return 0;
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poll_wait(file, &devp->hd_waitqueue, wait);
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spin_lock_irq(&hpet_lock);
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v = devp->hd_irqdata;
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spin_unlock_irq(&hpet_lock);
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if (v != 0)
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return EPOLLIN | EPOLLRDNORM;
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return 0;
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}
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#ifdef CONFIG_HPET_MMAP
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#ifdef CONFIG_HPET_MMAP_DEFAULT
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static int hpet_mmap_enabled = 1;
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#else
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static int hpet_mmap_enabled = 0;
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#endif
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static __init int hpet_mmap_enable(char *str)
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{
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get_option(&str, &hpet_mmap_enabled);
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pr_info("HPET mmap %s\n", hpet_mmap_enabled ? "enabled" : "disabled");
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return 1;
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}
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__setup("hpet_mmap=", hpet_mmap_enable);
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static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
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{
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struct hpet_dev *devp;
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unsigned long addr;
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if (!hpet_mmap_enabled)
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return -EACCES;
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devp = file->private_data;
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addr = devp->hd_hpets->hp_hpet_phys;
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if (addr & (PAGE_SIZE - 1))
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return -ENOSYS;
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vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
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return vm_iomap_memory(vma, addr, PAGE_SIZE);
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}
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#else
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static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
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{
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return -ENOSYS;
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}
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#endif
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|
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static int hpet_fasync(int fd, struct file *file, int on)
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{
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struct hpet_dev *devp;
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devp = file->private_data;
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if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0)
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return 0;
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else
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return -EIO;
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}
|
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static int hpet_release(struct inode *inode, struct file *file)
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{
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struct hpet_dev *devp;
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struct hpet_timer __iomem *timer;
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int irq = 0;
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devp = file->private_data;
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timer = devp->hd_timer;
|
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spin_lock_irq(&hpet_lock);
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|
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writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
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&timer->hpet_config);
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irq = devp->hd_irq;
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devp->hd_irq = 0;
|
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devp->hd_ireqfreq = 0;
|
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|
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if (devp->hd_flags & HPET_PERIODIC
|
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&& readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
|
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unsigned long v;
|
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|
||
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v = readq(&timer->hpet_config);
|
||
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v ^= Tn_TYPE_CNF_MASK;
|
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writeq(v, &timer->hpet_config);
|
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}
|
||
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|
||
|
devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
|
||
|
spin_unlock_irq(&hpet_lock);
|
||
|
|
||
|
if (irq)
|
||
|
free_irq(irq, devp);
|
||
|
|
||
|
file->private_data = NULL;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int hpet_ioctl_ieon(struct hpet_dev *devp)
|
||
|
{
|
||
|
struct hpet_timer __iomem *timer;
|
||
|
struct hpet __iomem *hpet;
|
||
|
struct hpets *hpetp;
|
||
|
int irq;
|
||
|
unsigned long g, v, t, m;
|
||
|
unsigned long flags, isr;
|
||
|
|
||
|
timer = devp->hd_timer;
|
||
|
hpet = devp->hd_hpet;
|
||
|
hpetp = devp->hd_hpets;
|
||
|
|
||
|
if (!devp->hd_ireqfreq)
|
||
|
return -EIO;
|
||
|
|
||
|
spin_lock_irq(&hpet_lock);
|
||
|
|
||
|
if (devp->hd_flags & HPET_IE) {
|
||
|
spin_unlock_irq(&hpet_lock);
|
||
|
return -EBUSY;
|
||
|
}
|
||
|
|
||
|
devp->hd_flags |= HPET_IE;
|
||
|
|
||
|
if (readl(&timer->hpet_config) & Tn_INT_TYPE_CNF_MASK)
|
||
|
devp->hd_flags |= HPET_SHARED_IRQ;
|
||
|
spin_unlock_irq(&hpet_lock);
|
||
|
|
||
|
irq = devp->hd_hdwirq;
|
||
|
|
||
|
if (irq) {
|
||
|
unsigned long irq_flags;
|
||
|
|
||
|
if (devp->hd_flags & HPET_SHARED_IRQ) {
|
||
|
/*
|
||
|
* To prevent the interrupt handler from seeing an
|
||
|
* unwanted interrupt status bit, program the timer
|
||
|
* so that it will not fire in the near future ...
|
||
|
*/
|
||
|
writel(readl(&timer->hpet_config) & ~Tn_TYPE_CNF_MASK,
|
||
|
&timer->hpet_config);
|
||
|
write_counter(read_counter(&hpet->hpet_mc),
|
||
|
&timer->hpet_compare);
|
||
|
/* ... and clear any left-over status. */
|
||
|
isr = 1 << (devp - devp->hd_hpets->hp_dev);
|
||
|
writel(isr, &hpet->hpet_isr);
|
||
|
}
|
||
|
|
||
|
sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
|
||
|
irq_flags = devp->hd_flags & HPET_SHARED_IRQ ? IRQF_SHARED : 0;
|
||
|
if (request_irq(irq, hpet_interrupt, irq_flags,
|
||
|
devp->hd_name, (void *)devp)) {
|
||
|
printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
|
||
|
irq = 0;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (irq == 0) {
|
||
|
spin_lock_irq(&hpet_lock);
|
||
|
devp->hd_flags ^= HPET_IE;
|
||
|
spin_unlock_irq(&hpet_lock);
|
||
|
return -EIO;
|
||
|
}
|
||
|
|
||
|
devp->hd_irq = irq;
|
||
|
t = devp->hd_ireqfreq;
|
||
|
v = readq(&timer->hpet_config);
|
||
|
|
||
|
/* 64-bit comparators are not yet supported through the ioctls,
|
||
|
* so force this into 32-bit mode if it supports both modes
|
||
|
*/
|
||
|
g = v | Tn_32MODE_CNF_MASK | Tn_INT_ENB_CNF_MASK;
|
||
|
|
||
|
if (devp->hd_flags & HPET_PERIODIC) {
|
||
|
g |= Tn_TYPE_CNF_MASK;
|
||
|
v |= Tn_TYPE_CNF_MASK | Tn_VAL_SET_CNF_MASK;
|
||
|
writeq(v, &timer->hpet_config);
|
||
|
local_irq_save(flags);
|
||
|
|
||
|
/*
|
||
|
* NOTE: First we modify the hidden accumulator
|
||
|
* register supported by periodic-capable comparators.
|
||
|
* We never want to modify the (single) counter; that
|
||
|
* would affect all the comparators. The value written
|
||
|
* is the counter value when the first interrupt is due.
|
||
|
*/
|
||
|
m = read_counter(&hpet->hpet_mc);
|
||
|
write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
|
||
|
/*
|
||
|
* Then we modify the comparator, indicating the period
|
||
|
* for subsequent interrupt.
|
||
|
*/
|
||
|
write_counter(t, &timer->hpet_compare);
|
||
|
} else {
|
||
|
local_irq_save(flags);
|
||
|
m = read_counter(&hpet->hpet_mc);
|
||
|
write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
|
||
|
}
|
||
|
|
||
|
if (devp->hd_flags & HPET_SHARED_IRQ) {
|
||
|
isr = 1 << (devp - devp->hd_hpets->hp_dev);
|
||
|
writel(isr, &hpet->hpet_isr);
|
||
|
}
|
||
|
writeq(g, &timer->hpet_config);
|
||
|
local_irq_restore(flags);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/* converts Hz to number of timer ticks */
|
||
|
static inline unsigned long hpet_time_div(struct hpets *hpets,
|
||
|
unsigned long dis)
|
||
|
{
|
||
|
unsigned long long m;
|
||
|
|
||
|
m = hpets->hp_tick_freq + (dis >> 1);
|
||
|
return div64_ul(m, dis);
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
hpet_ioctl_common(struct hpet_dev *devp, unsigned int cmd, unsigned long arg,
|
||
|
struct hpet_info *info)
|
||
|
{
|
||
|
struct hpet_timer __iomem *timer;
|
||
|
struct hpets *hpetp;
|
||
|
int err;
|
||
|
unsigned long v;
|
||
|
|
||
|
switch (cmd) {
|
||
|
case HPET_IE_OFF:
|
||
|
case HPET_INFO:
|
||
|
case HPET_EPI:
|
||
|
case HPET_DPI:
|
||
|
case HPET_IRQFREQ:
|
||
|
timer = devp->hd_timer;
|
||
|
hpetp = devp->hd_hpets;
|
||
|
break;
|
||
|
case HPET_IE_ON:
|
||
|
return hpet_ioctl_ieon(devp);
|
||
|
default:
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
err = 0;
|
||
|
|
||
|
switch (cmd) {
|
||
|
case HPET_IE_OFF:
|
||
|
if ((devp->hd_flags & HPET_IE) == 0)
|
||
|
break;
|
||
|
v = readq(&timer->hpet_config);
|
||
|
v &= ~Tn_INT_ENB_CNF_MASK;
|
||
|
writeq(v, &timer->hpet_config);
|
||
|
if (devp->hd_irq) {
|
||
|
free_irq(devp->hd_irq, devp);
|
||
|
devp->hd_irq = 0;
|
||
|
}
|
||
|
devp->hd_flags ^= HPET_IE;
|
||
|
break;
|
||
|
case HPET_INFO:
|
||
|
{
|
||
|
memset(info, 0, sizeof(*info));
|
||
|
if (devp->hd_ireqfreq)
|
||
|
info->hi_ireqfreq =
|
||
|
hpet_time_div(hpetp, devp->hd_ireqfreq);
|
||
|
info->hi_flags =
|
||
|
readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK;
|
||
|
info->hi_hpet = hpetp->hp_which;
|
||
|
info->hi_timer = devp - hpetp->hp_dev;
|
||
|
break;
|
||
|
}
|
||
|
case HPET_EPI:
|
||
|
v = readq(&timer->hpet_config);
|
||
|
if ((v & Tn_PER_INT_CAP_MASK) == 0) {
|
||
|
err = -ENXIO;
|
||
|
break;
|
||
|
}
|
||
|
devp->hd_flags |= HPET_PERIODIC;
|
||
|
break;
|
||
|
case HPET_DPI:
|
||
|
v = readq(&timer->hpet_config);
|
||
|
if ((v & Tn_PER_INT_CAP_MASK) == 0) {
|
||
|
err = -ENXIO;
|
||
|
break;
|
||
|
}
|
||
|
if (devp->hd_flags & HPET_PERIODIC &&
|
||
|
readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
|
||
|
v = readq(&timer->hpet_config);
|
||
|
v ^= Tn_TYPE_CNF_MASK;
|
||
|
writeq(v, &timer->hpet_config);
|
||
|
}
|
||
|
devp->hd_flags &= ~HPET_PERIODIC;
|
||
|
break;
|
||
|
case HPET_IRQFREQ:
|
||
|
if ((arg > hpet_max_freq) &&
|
||
|
!capable(CAP_SYS_RESOURCE)) {
|
||
|
err = -EACCES;
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
if (!arg) {
|
||
|
err = -EINVAL;
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
devp->hd_ireqfreq = hpet_time_div(hpetp, arg);
|
||
|
}
|
||
|
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
static long
|
||
|
hpet_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
||
|
{
|
||
|
struct hpet_info info;
|
||
|
int err;
|
||
|
|
||
|
mutex_lock(&hpet_mutex);
|
||
|
err = hpet_ioctl_common(file->private_data, cmd, arg, &info);
|
||
|
mutex_unlock(&hpet_mutex);
|
||
|
|
||
|
if ((cmd == HPET_INFO) && !err &&
|
||
|
(copy_to_user((void __user *)arg, &info, sizeof(info))))
|
||
|
err = -EFAULT;
|
||
|
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_COMPAT
|
||
|
struct compat_hpet_info {
|
||
|
compat_ulong_t hi_ireqfreq; /* Hz */
|
||
|
compat_ulong_t hi_flags; /* information */
|
||
|
unsigned short hi_hpet;
|
||
|
unsigned short hi_timer;
|
||
|
};
|
||
|
|
||
|
static long
|
||
|
hpet_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
||
|
{
|
||
|
struct hpet_info info;
|
||
|
int err;
|
||
|
|
||
|
mutex_lock(&hpet_mutex);
|
||
|
err = hpet_ioctl_common(file->private_data, cmd, arg, &info);
|
||
|
mutex_unlock(&hpet_mutex);
|
||
|
|
||
|
if ((cmd == HPET_INFO) && !err) {
|
||
|
struct compat_hpet_info __user *u = compat_ptr(arg);
|
||
|
if (put_user(info.hi_ireqfreq, &u->hi_ireqfreq) ||
|
||
|
put_user(info.hi_flags, &u->hi_flags) ||
|
||
|
put_user(info.hi_hpet, &u->hi_hpet) ||
|
||
|
put_user(info.hi_timer, &u->hi_timer))
|
||
|
err = -EFAULT;
|
||
|
}
|
||
|
|
||
|
return err;
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
static const struct file_operations hpet_fops = {
|
||
|
.owner = THIS_MODULE,
|
||
|
.llseek = no_llseek,
|
||
|
.read = hpet_read,
|
||
|
.poll = hpet_poll,
|
||
|
.unlocked_ioctl = hpet_ioctl,
|
||
|
#ifdef CONFIG_COMPAT
|
||
|
.compat_ioctl = hpet_compat_ioctl,
|
||
|
#endif
|
||
|
.open = hpet_open,
|
||
|
.release = hpet_release,
|
||
|
.fasync = hpet_fasync,
|
||
|
.mmap = hpet_mmap,
|
||
|
};
|
||
|
|
||
|
static int hpet_is_known(struct hpet_data *hdp)
|
||
|
{
|
||
|
struct hpets *hpetp;
|
||
|
|
||
|
for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
|
||
|
if (hpetp->hp_hpet_phys == hdp->hd_phys_address)
|
||
|
return 1;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static struct ctl_table hpet_table[] = {
|
||
|
{
|
||
|
.procname = "max-user-freq",
|
||
|
.data = &hpet_max_freq,
|
||
|
.maxlen = sizeof(int),
|
||
|
.mode = 0644,
|
||
|
.proc_handler = proc_dointvec,
|
||
|
},
|
||
|
{}
|
||
|
};
|
||
|
|
||
|
static struct ctl_table_header *sysctl_header;
|
||
|
|
||
|
/*
|
||
|
* Adjustment for when arming the timer with
|
||
|
* initial conditions. That is, main counter
|
||
|
* ticks expired before interrupts are enabled.
|
||
|
*/
|
||
|
#define TICK_CALIBRATE (1000UL)
|
||
|
|
||
|
static unsigned long __hpet_calibrate(struct hpets *hpetp)
|
||
|
{
|
||
|
struct hpet_timer __iomem *timer = NULL;
|
||
|
unsigned long t, m, count, i, flags, start;
|
||
|
struct hpet_dev *devp;
|
||
|
int j;
|
||
|
struct hpet __iomem *hpet;
|
||
|
|
||
|
for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++)
|
||
|
if ((devp->hd_flags & HPET_OPEN) == 0) {
|
||
|
timer = devp->hd_timer;
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
if (!timer)
|
||
|
return 0;
|
||
|
|
||
|
hpet = hpetp->hp_hpet;
|
||
|
t = read_counter(&timer->hpet_compare);
|
||
|
|
||
|
i = 0;
|
||
|
count = hpet_time_div(hpetp, TICK_CALIBRATE);
|
||
|
|
||
|
local_irq_save(flags);
|
||
|
|
||
|
start = read_counter(&hpet->hpet_mc);
|
||
|
|
||
|
do {
|
||
|
m = read_counter(&hpet->hpet_mc);
|
||
|
write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
|
||
|
} while (i++, (m - start) < count);
|
||
|
|
||
|
local_irq_restore(flags);
|
||
|
|
||
|
return (m - start) / i;
|
||
|
}
|
||
|
|
||
|
static unsigned long hpet_calibrate(struct hpets *hpetp)
|
||
|
{
|
||
|
unsigned long ret = ~0UL;
|
||
|
unsigned long tmp;
|
||
|
|
||
|
/*
|
||
|
* Try to calibrate until return value becomes stable small value.
|
||
|
* If SMI interruption occurs in calibration loop, the return value
|
||
|
* will be big. This avoids its impact.
|
||
|
*/
|
||
|
for ( ; ; ) {
|
||
|
tmp = __hpet_calibrate(hpetp);
|
||
|
if (ret <= tmp)
|
||
|
break;
|
||
|
ret = tmp;
|
||
|
}
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
int hpet_alloc(struct hpet_data *hdp)
|
||
|
{
|
||
|
u64 cap, mcfg;
|
||
|
struct hpet_dev *devp;
|
||
|
u32 i, ntimer;
|
||
|
struct hpets *hpetp;
|
||
|
struct hpet __iomem *hpet;
|
||
|
static struct hpets *last;
|
||
|
unsigned long period;
|
||
|
unsigned long long temp;
|
||
|
u32 remainder;
|
||
|
|
||
|
/*
|
||
|
* hpet_alloc can be called by platform dependent code.
|
||
|
* If platform dependent code has allocated the hpet that
|
||
|
* ACPI has also reported, then we catch it here.
|
||
|
*/
|
||
|
if (hpet_is_known(hdp)) {
|
||
|
printk(KERN_DEBUG "%s: duplicate HPET ignored\n",
|
||
|
__func__);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
hpetp = kzalloc(struct_size(hpetp, hp_dev, hdp->hd_nirqs),
|
||
|
GFP_KERNEL);
|
||
|
|
||
|
if (!hpetp)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
hpetp->hp_which = hpet_nhpet++;
|
||
|
hpetp->hp_hpet = hdp->hd_address;
|
||
|
hpetp->hp_hpet_phys = hdp->hd_phys_address;
|
||
|
|
||
|
hpetp->hp_ntimer = hdp->hd_nirqs;
|
||
|
|
||
|
for (i = 0; i < hdp->hd_nirqs; i++)
|
||
|
hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
|
||
|
|
||
|
hpet = hpetp->hp_hpet;
|
||
|
|
||
|
cap = readq(&hpet->hpet_cap);
|
||
|
|
||
|
ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1;
|
||
|
|
||
|
if (hpetp->hp_ntimer != ntimer) {
|
||
|
printk(KERN_WARNING "hpet: number irqs doesn't agree"
|
||
|
" with number of timers\n");
|
||
|
kfree(hpetp);
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
if (last)
|
||
|
last->hp_next = hpetp;
|
||
|
else
|
||
|
hpets = hpetp;
|
||
|
|
||
|
last = hpetp;
|
||
|
|
||
|
period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
|
||
|
HPET_COUNTER_CLK_PERIOD_SHIFT; /* fs, 10^-15 */
|
||
|
temp = 1000000000000000uLL; /* 10^15 femtoseconds per second */
|
||
|
temp += period >> 1; /* round */
|
||
|
do_div(temp, period);
|
||
|
hpetp->hp_tick_freq = temp; /* ticks per second */
|
||
|
|
||
|
printk(KERN_INFO "hpet%d: at MMIO 0x%lx, IRQ%s",
|
||
|
hpetp->hp_which, hdp->hd_phys_address,
|
||
|
hpetp->hp_ntimer > 1 ? "s" : "");
|
||
|
for (i = 0; i < hpetp->hp_ntimer; i++)
|
||
|
printk(KERN_CONT "%s %d", i > 0 ? "," : "", hdp->hd_irq[i]);
|
||
|
printk(KERN_CONT "\n");
|
||
|
|
||
|
temp = hpetp->hp_tick_freq;
|
||
|
remainder = do_div(temp, 1000000);
|
||
|
printk(KERN_INFO
|
||
|
"hpet%u: %u comparators, %d-bit %u.%06u MHz counter\n",
|
||
|
hpetp->hp_which, hpetp->hp_ntimer,
|
||
|
cap & HPET_COUNTER_SIZE_MASK ? 64 : 32,
|
||
|
(unsigned) temp, remainder);
|
||
|
|
||
|
mcfg = readq(&hpet->hpet_config);
|
||
|
if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) {
|
||
|
write_counter(0L, &hpet->hpet_mc);
|
||
|
mcfg |= HPET_ENABLE_CNF_MASK;
|
||
|
writeq(mcfg, &hpet->hpet_config);
|
||
|
}
|
||
|
|
||
|
for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++, devp++) {
|
||
|
struct hpet_timer __iomem *timer;
|
||
|
|
||
|
timer = &hpet->hpet_timers[devp - hpetp->hp_dev];
|
||
|
|
||
|
devp->hd_hpets = hpetp;
|
||
|
devp->hd_hpet = hpet;
|
||
|
devp->hd_timer = timer;
|
||
|
|
||
|
/*
|
||
|
* If the timer was reserved by platform code,
|
||
|
* then make timer unavailable for opens.
|
||
|
*/
|
||
|
if (hdp->hd_state & (1 << i)) {
|
||
|
devp->hd_flags = HPET_OPEN;
|
||
|
continue;
|
||
|
}
|
||
|
|
||
|
init_waitqueue_head(&devp->hd_waitqueue);
|
||
|
}
|
||
|
|
||
|
hpetp->hp_delta = hpet_calibrate(hpetp);
|
||
|
|
||
|
/* This clocksource driver currently only works on ia64 */
|
||
|
#ifdef CONFIG_IA64
|
||
|
if (!hpet_clocksource) {
|
||
|
hpet_mctr = (void __iomem *)&hpetp->hp_hpet->hpet_mc;
|
||
|
clocksource_hpet.archdata.fsys_mmio = hpet_mctr;
|
||
|
clocksource_register_hz(&clocksource_hpet, hpetp->hp_tick_freq);
|
||
|
hpetp->hp_clocksource = &clocksource_hpet;
|
||
|
hpet_clocksource = &clocksource_hpet;
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static acpi_status hpet_resources(struct acpi_resource *res, void *data)
|
||
|
{
|
||
|
struct hpet_data *hdp;
|
||
|
acpi_status status;
|
||
|
struct acpi_resource_address64 addr;
|
||
|
|
||
|
hdp = data;
|
||
|
|
||
|
status = acpi_resource_to_address64(res, &addr);
|
||
|
|
||
|
if (ACPI_SUCCESS(status)) {
|
||
|
hdp->hd_phys_address = addr.address.minimum;
|
||
|
hdp->hd_address = ioremap(addr.address.minimum, addr.address.address_length);
|
||
|
if (!hdp->hd_address)
|
||
|
return AE_ERROR;
|
||
|
|
||
|
if (hpet_is_known(hdp)) {
|
||
|
iounmap(hdp->hd_address);
|
||
|
return AE_ALREADY_EXISTS;
|
||
|
}
|
||
|
} else if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
|
||
|
struct acpi_resource_fixed_memory32 *fixmem32;
|
||
|
|
||
|
fixmem32 = &res->data.fixed_memory32;
|
||
|
|
||
|
hdp->hd_phys_address = fixmem32->address;
|
||
|
hdp->hd_address = ioremap(fixmem32->address,
|
||
|
HPET_RANGE_SIZE);
|
||
|
if (!hdp->hd_address)
|
||
|
return AE_ERROR;
|
||
|
|
||
|
if (hpet_is_known(hdp)) {
|
||
|
iounmap(hdp->hd_address);
|
||
|
return AE_ALREADY_EXISTS;
|
||
|
}
|
||
|
} else if (res->type == ACPI_RESOURCE_TYPE_EXTENDED_IRQ) {
|
||
|
struct acpi_resource_extended_irq *irqp;
|
||
|
int i, irq;
|
||
|
|
||
|
irqp = &res->data.extended_irq;
|
||
|
|
||
|
for (i = 0; i < irqp->interrupt_count; i++) {
|
||
|
if (hdp->hd_nirqs >= HPET_MAX_TIMERS)
|
||
|
break;
|
||
|
|
||
|
irq = acpi_register_gsi(NULL, irqp->interrupts[i],
|
||
|
irqp->triggering,
|
||
|
irqp->polarity);
|
||
|
if (irq < 0)
|
||
|
return AE_ERROR;
|
||
|
|
||
|
hdp->hd_irq[hdp->hd_nirqs] = irq;
|
||
|
hdp->hd_nirqs++;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return AE_OK;
|
||
|
}
|
||
|
|
||
|
static int hpet_acpi_add(struct acpi_device *device)
|
||
|
{
|
||
|
acpi_status result;
|
||
|
struct hpet_data data;
|
||
|
|
||
|
memset(&data, 0, sizeof(data));
|
||
|
|
||
|
result =
|
||
|
acpi_walk_resources(device->handle, METHOD_NAME__CRS,
|
||
|
hpet_resources, &data);
|
||
|
|
||
|
if (ACPI_FAILURE(result))
|
||
|
return -ENODEV;
|
||
|
|
||
|
if (!data.hd_address || !data.hd_nirqs) {
|
||
|
if (data.hd_address)
|
||
|
iounmap(data.hd_address);
|
||
|
printk("%s: no address or irqs in _CRS\n", __func__);
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
return hpet_alloc(&data);
|
||
|
}
|
||
|
|
||
|
static const struct acpi_device_id hpet_device_ids[] = {
|
||
|
{"PNP0103", 0},
|
||
|
{"", 0},
|
||
|
};
|
||
|
|
||
|
static struct acpi_driver hpet_acpi_driver = {
|
||
|
.name = "hpet",
|
||
|
.ids = hpet_device_ids,
|
||
|
.ops = {
|
||
|
.add = hpet_acpi_add,
|
||
|
},
|
||
|
};
|
||
|
|
||
|
static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops };
|
||
|
|
||
|
static int __init hpet_init(void)
|
||
|
{
|
||
|
int result;
|
||
|
|
||
|
result = misc_register(&hpet_misc);
|
||
|
if (result < 0)
|
||
|
return -ENODEV;
|
||
|
|
||
|
sysctl_header = register_sysctl("dev/hpet", hpet_table);
|
||
|
|
||
|
result = acpi_bus_register_driver(&hpet_acpi_driver);
|
||
|
if (result < 0) {
|
||
|
if (sysctl_header)
|
||
|
unregister_sysctl_table(sysctl_header);
|
||
|
misc_deregister(&hpet_misc);
|
||
|
return result;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
device_initcall(hpet_init);
|
||
|
|
||
|
/*
|
||
|
MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
|
||
|
MODULE_LICENSE("GPL");
|
||
|
*/
|