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[/] [test_project/] [trunk/] [linux_sd_driver/] [drivers/] [char/] [hpet.c] - Blame information for rev 62

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/*
 * Intel & MS High Precision Event Timer Implementation.
 *
 * Copyright (C) 2003 Intel Corporation
 *      Venki Pallipadi
 * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
 *      Bob Picco <robert.picco@hp.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
 
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
#include <linux/major.h>
#include <linux/ioport.h>
#include <linux/fcntl.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/sysctl.h>
#include <linux/wait.h>
#include <linux/bcd.h>
#include <linux/seq_file.h>
#include <linux/bitops.h>
#include <linux/clocksource.h>
 
#include <asm/current.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/div64.h>
 
#include <linux/acpi.h>
#include <acpi/acpi_bus.h>
#include <linux/hpet.h>
 
/*
 * The High Precision Event Timer driver.
 * This driver is closely modelled after the rtc.c driver.
 * http://www.intel.com/hardwaredesign/hpetspec.htm
 */
#define HPET_USER_FREQ  (64)
#define HPET_DRIFT      (500)
 
#define HPET_RANGE_SIZE         1024    /* from HPET spec */
 
#if BITS_PER_LONG == 64
#define write_counter(V, MC)    writeq(V, MC)
#define read_counter(MC)        readq(MC)
#else
#define write_counter(V, MC)    writel(V, MC)
#define read_counter(MC)        readl(MC)
#endif
 
static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
 
/* This clocksource driver currently only works on ia64 */
#ifdef CONFIG_IA64
static void __iomem *hpet_mctr;
 
static cycle_t read_hpet(void)
{
        return (cycle_t)read_counter((void __iomem *)hpet_mctr);
}
 
static struct clocksource clocksource_hpet = {
        .name           = "hpet",
        .rating         = 250,
        .read           = read_hpet,
        .mask           = CLOCKSOURCE_MASK(64),
        .mult           = 0, /*to be caluclated*/
        .shift          = 10,
        .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
};
static struct clocksource *hpet_clocksource;
#endif
 
/* A lock for concurrent access by app and isr hpet activity. */
static DEFINE_SPINLOCK(hpet_lock);
/* A lock for concurrent intermodule access to hpet and isr hpet activity. */
static DEFINE_SPINLOCK(hpet_task_lock);
 
#define HPET_DEV_NAME   (7)
 
struct hpet_dev {
        struct hpets *hd_hpets;
        struct hpet __iomem *hd_hpet;
        struct hpet_timer __iomem *hd_timer;
        unsigned long hd_ireqfreq;
        unsigned long hd_irqdata;
        wait_queue_head_t hd_waitqueue;
        struct fasync_struct *hd_async_queue;
        struct hpet_task *hd_task;
        unsigned int hd_flags;
        unsigned int hd_irq;
        unsigned int hd_hdwirq;
        char hd_name[HPET_DEV_NAME];
};
 
struct hpets {
        struct hpets *hp_next;
        struct hpet __iomem *hp_hpet;
        unsigned long hp_hpet_phys;
        struct clocksource *hp_clocksource;
        unsigned long long hp_tick_freq;
        unsigned long hp_delta;
        unsigned int hp_ntimer;
        unsigned int hp_which;
        struct hpet_dev hp_dev[1];
};
 
static struct hpets *hpets;
 
#define HPET_OPEN               0x0001
#define HPET_IE                 0x0002  /* interrupt enabled */
#define HPET_PERIODIC           0x0004
#define HPET_SHARED_IRQ         0x0008
 
 
#ifndef readq
static inline unsigned long long readq(void __iomem *addr)
{
        return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL);
}
#endif
 
#ifndef writeq
static inline void writeq(unsigned long long v, void __iomem *addr)
{
        writel(v & 0xffffffff, addr);
        writel(v >> 32, addr + 4);
}
#endif
 
static irqreturn_t hpet_interrupt(int irq, void *data)
{
        struct hpet_dev *devp;
        unsigned long isr;
 
        devp = data;
        isr = 1 << (devp - devp->hd_hpets->hp_dev);
 
        if ((devp->hd_flags & HPET_SHARED_IRQ) &&
            !(isr & readl(&devp->hd_hpet->hpet_isr)))
                return IRQ_NONE;
 
        spin_lock(&hpet_lock);
        devp->hd_irqdata++;
 
        /*
         * For non-periodic timers, increment the accumulator.
         * This has the effect of treating non-periodic like periodic.
         */
        if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
                unsigned long m, t;
 
                t = devp->hd_ireqfreq;
                m = read_counter(&devp->hd_hpet->hpet_mc);
                write_counter(t + m + devp->hd_hpets->hp_delta,
                              &devp->hd_timer->hpet_compare);
        }
 
        if (devp->hd_flags & HPET_SHARED_IRQ)
                writel(isr, &devp->hd_hpet->hpet_isr);
        spin_unlock(&hpet_lock);
 
        spin_lock(&hpet_task_lock);
        if (devp->hd_task)
                devp->hd_task->ht_func(devp->hd_task->ht_data);
        spin_unlock(&hpet_task_lock);
 
        wake_up_interruptible(&devp->hd_waitqueue);
 
        kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
 
        return IRQ_HANDLED;
}
 
static int hpet_open(struct inode *inode, struct file *file)
{
        struct hpet_dev *devp;
        struct hpets *hpetp;
        int i;
 
        if (file->f_mode & FMODE_WRITE)
                return -EINVAL;
 
        spin_lock_irq(&hpet_lock);
 
        for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
                for (i = 0; i < hpetp->hp_ntimer; i++)
                        if (hpetp->hp_dev[i].hd_flags & HPET_OPEN
                            || hpetp->hp_dev[i].hd_task)
                                continue;
                        else {
                                devp = &hpetp->hp_dev[i];
                                break;
                        }
 
        if (!devp) {
                spin_unlock_irq(&hpet_lock);
                return -EBUSY;
        }
 
        file->private_data = devp;
        devp->hd_irqdata = 0;
        devp->hd_flags |= HPET_OPEN;
        spin_unlock_irq(&hpet_lock);
 
        return 0;
}
 
static ssize_t
hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
{
        DECLARE_WAITQUEUE(wait, current);
        unsigned long data;
        ssize_t retval;
        struct hpet_dev *devp;
 
        devp = file->private_data;
        if (!devp->hd_ireqfreq)
                return -EIO;
 
        if (count < sizeof(unsigned long))
                return -EINVAL;
 
        add_wait_queue(&devp->hd_waitqueue, &wait);
 
        for ( ; ; ) {
                set_current_state(TASK_INTERRUPTIBLE);
 
                spin_lock_irq(&hpet_lock);
                data = devp->hd_irqdata;
                devp->hd_irqdata = 0;
                spin_unlock_irq(&hpet_lock);
 
                if (data)
                        break;
                else if (file->f_flags & O_NONBLOCK) {
                        retval = -EAGAIN;
                        goto out;
                } else if (signal_pending(current)) {
                        retval = -ERESTARTSYS;
                        goto out;
                }
                schedule();
        }
 
        retval = put_user(data, (unsigned long __user *)buf);
        if (!retval)
                retval = sizeof(unsigned long);
out:
        __set_current_state(TASK_RUNNING);
        remove_wait_queue(&devp->hd_waitqueue, &wait);
 
        return retval;
}
 
static unsigned int hpet_poll(struct file *file, poll_table * wait)
{
        unsigned long v;
        struct hpet_dev *devp;
 
        devp = file->private_data;
 
        if (!devp->hd_ireqfreq)
                return 0;
 
        poll_wait(file, &devp->hd_waitqueue, wait);
 
        spin_lock_irq(&hpet_lock);
        v = devp->hd_irqdata;
        spin_unlock_irq(&hpet_lock);
 
        if (v != 0)
                return POLLIN | POLLRDNORM;
 
        return 0;
}
 
static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
{
#ifdef  CONFIG_HPET_MMAP
        struct hpet_dev *devp;
        unsigned long addr;
 
        if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff)
                return -EINVAL;
 
        devp = file->private_data;
        addr = devp->hd_hpets->hp_hpet_phys;
 
        if (addr & (PAGE_SIZE - 1))
                return -ENOSYS;
 
        vma->vm_flags |= VM_IO;
        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
        if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT,
                                        PAGE_SIZE, vma->vm_page_prot)) {
                printk(KERN_ERR "%s: io_remap_pfn_range failed\n",
                        __FUNCTION__);
                return -EAGAIN;
        }
 
        return 0;
#else
        return -ENOSYS;
#endif
}
 
static int hpet_fasync(int fd, struct file *file, int on)
{
        struct hpet_dev *devp;
 
        devp = file->private_data;
 
        if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0)
                return 0;
        else
                return -EIO;
}
 
static int hpet_release(struct inode *inode, struct file *file)
{
        struct hpet_dev *devp;
        struct hpet_timer __iomem *timer;
        int irq = 0;
 
        devp = file->private_data;
        timer = devp->hd_timer;
 
        spin_lock_irq(&hpet_lock);
 
        writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
               &timer->hpet_config);
 
        irq = devp->hd_irq;
        devp->hd_irq = 0;
 
        devp->hd_ireqfreq = 0;
 
        if (devp->hd_flags & HPET_PERIODIC
            && readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
                unsigned long v;
 
                v = readq(&timer->hpet_config);
                v ^= Tn_TYPE_CNF_MASK;
                writeq(v, &timer->hpet_config);
        }
 
        devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
        spin_unlock_irq(&hpet_lock);
 
        if (irq)
                free_irq(irq, devp);
 
        if (file->f_flags & FASYNC)
                hpet_fasync(-1, file, 0);
 
        file->private_data = NULL;
        return 0;
}
 
static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int);
 
static int
hpet_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
           unsigned long arg)
{
        struct hpet_dev *devp;
 
        devp = file->private_data;
        return hpet_ioctl_common(devp, cmd, arg, 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;
 
                sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
                irq_flags = devp->hd_flags & HPET_SHARED_IRQ
                                                ? IRQF_SHARED : IRQF_DISABLED;
                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);
        g = v | Tn_INT_ENB_CNF_MASK;
 
        if (devp->hd_flags & HPET_PERIODIC) {
                write_counter(t, &timer->hpet_compare);
                g |= Tn_TYPE_CNF_MASK;
                v |= Tn_TYPE_CNF_MASK;
                writeq(v, &timer->hpet_config);
                v |= Tn_VAL_SET_CNF_MASK;
                writeq(v, &timer->hpet_config);
                local_irq_save(flags);
                m = read_counter(&hpet->hpet_mc);
                write_counter(t + m + hpetp->hp_delta, &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);
        do_div(m, dis);
        return (unsigned long)m;
}
 
static int
hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel)
{
        struct hpet_timer __iomem *timer;
        struct hpet __iomem *hpet;
        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;
                hpet = devp->hd_hpet;
                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:
                {
                        struct hpet_info info;
 
                        if (devp->hd_ireqfreq)
                                info.hi_ireqfreq =
                                        hpet_time_div(hpetp, devp->hd_ireqfreq);
                        else
                                info.hi_ireqfreq = 0;
                        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;
                        if (kernel)
                                memcpy((void *)arg, &info, sizeof(info));
                        else
                                if (copy_to_user((void __user *)arg, &info,
                                                 sizeof(info)))
                                        err = -EFAULT;
                        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 (!kernel && (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 const struct file_operations hpet_fops = {
        .owner = THIS_MODULE,
        .llseek = no_llseek,
        .read = hpet_read,
        .poll = hpet_poll,
        .ioctl = hpet_ioctl,
        .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;
}
 
EXPORT_SYMBOL(hpet_alloc);
EXPORT_SYMBOL(hpet_register);
EXPORT_SYMBOL(hpet_unregister);
EXPORT_SYMBOL(hpet_control);
 
int hpet_register(struct hpet_task *tp, int periodic)
{
        unsigned int i;
        u64 mask;
        struct hpet_timer __iomem *timer;
        struct hpet_dev *devp;
        struct hpets *hpetp;
 
        switch (periodic) {
        case 1:
                mask = Tn_PER_INT_CAP_MASK;
                break;
        case 0:
                mask = 0;
                break;
        default:
                return -EINVAL;
        }
 
        tp->ht_opaque = NULL;
 
        spin_lock_irq(&hpet_task_lock);
        spin_lock(&hpet_lock);
 
        for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
                for (timer = hpetp->hp_hpet->hpet_timers, i = 0;
                     i < hpetp->hp_ntimer; i++, timer++) {
                        if ((readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK)
                            != mask)
                                continue;
 
                        devp = &hpetp->hp_dev[i];
 
                        if (devp->hd_flags & HPET_OPEN || devp->hd_task) {
                                devp = NULL;
                                continue;
                        }
 
                        tp->ht_opaque = devp;
                        devp->hd_task = tp;
                        break;
                }
 
        spin_unlock(&hpet_lock);
        spin_unlock_irq(&hpet_task_lock);
 
        if (tp->ht_opaque)
                return 0;
        else
                return -EBUSY;
}
 
static inline int hpet_tpcheck(struct hpet_task *tp)
{
        struct hpet_dev *devp;
        struct hpets *hpetp;
 
        devp = tp->ht_opaque;
 
        if (!devp)
                return -ENXIO;
 
        for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
                if (devp >= hpetp->hp_dev
                    && devp < (hpetp->hp_dev + hpetp->hp_ntimer)
                    && devp->hd_hpet == hpetp->hp_hpet)
                        return 0;
 
        return -ENXIO;
}
 
int hpet_unregister(struct hpet_task *tp)
{
        struct hpet_dev *devp;
        struct hpet_timer __iomem *timer;
        int err;
 
        if ((err = hpet_tpcheck(tp)))
                return err;
 
        spin_lock_irq(&hpet_task_lock);
        spin_lock(&hpet_lock);
 
        devp = tp->ht_opaque;
        if (devp->hd_task != tp) {
                spin_unlock(&hpet_lock);
                spin_unlock_irq(&hpet_task_lock);
                return -ENXIO;
        }
 
        timer = devp->hd_timer;
        writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
               &timer->hpet_config);
        devp->hd_flags &= ~(HPET_IE | HPET_PERIODIC);
        devp->hd_task = NULL;
        spin_unlock(&hpet_lock);
        spin_unlock_irq(&hpet_task_lock);
 
        return 0;
}
 
int hpet_control(struct hpet_task *tp, unsigned int cmd, unsigned long arg)
{
        struct hpet_dev *devp;
        int err;
 
        if ((err = hpet_tpcheck(tp)))
                return err;
 
        spin_lock_irq(&hpet_lock);
        devp = tp->ht_opaque;
        if (devp->hd_task != tp) {
                spin_unlock_irq(&hpet_lock);
                return -ENXIO;
        }
        spin_unlock_irq(&hpet_lock);
        return hpet_ioctl_common(devp, cmd, arg, 1);
}
 
static ctl_table hpet_table[] = {
        {
         .ctl_name = CTL_UNNUMBERED,
         .procname = "max-user-freq",
         .data = &hpet_max_freq,
         .maxlen = sizeof(int),
         .mode = 0644,
         .proc_handler = &proc_dointvec,
         },
        {.ctl_name = 0}
};
 
static ctl_table hpet_root[] = {
        {
         .ctl_name = CTL_UNNUMBERED,
         .procname = "hpet",
         .maxlen = 0,
         .mode = 0555,
         .child = hpet_table,
         },
        {.ctl_name = 0}
};
 
static ctl_table dev_root[] = {
        {
         .ctl_name = CTL_DEV,
         .procname = "dev",
         .maxlen = 0,
         .mode = 0555,
         .child = hpet_root,
         },
        {.ctl_name = 0}
};
 
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;
}
 
int hpet_alloc(struct hpet_data *hdp)
{
        u64 cap, mcfg;
        struct hpet_dev *devp;
        u32 i, ntimer;
        struct hpets *hpetp;
        size_t siz;
        struct hpet __iomem *hpet;
        static struct hpets *last = NULL;
        unsigned long period;
        unsigned long long temp;
 
        /*
         * 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",
                        __FUNCTION__);
                return 0;
        }
 
        siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) *
                                      sizeof(struct hpet_dev));
 
        hpetp = kzalloc(siz, 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("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]);
        printk("\n");
 
        printk(KERN_INFO "hpet%u: %u %d-bit timers, %Lu Hz\n",
               hpetp->hp_which, hpetp->hp_ntimer,
               cap & HPET_COUNTER_SIZE_MASK ? 64 : 32, hpetp->hp_tick_freq);
 
        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;
                CLKSRC_FSYS_MMIO_SET(clocksource_hpet.fsys_mmio, hpet_mctr);
                clocksource_hpet.mult = clocksource_hz2mult(hpetp->hp_tick_freq,
                                                clocksource_hpet.shift);
                clocksource_register(&clocksource_hpet);
                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.minimum;
                hdp->hd_address = ioremap(addr.minimum, addr.address_length);
 
                if (hpet_is_known(hdp)) {
                        printk(KERN_DEBUG "%s: 0x%lx is busy\n",
                                __FUNCTION__, hdp->hd_phys_address);
                        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;
                if (!fixmem32)
                        return AE_NO_MEMORY;
 
                hdp->hd_phys_address = fixmem32->address;
                hdp->hd_address = ioremap(fixmem32->address,
                                                HPET_RANGE_SIZE);
 
                if (hpet_is_known(hdp)) {
                        printk(KERN_DEBUG "%s: 0x%lx is busy\n",
                                __FUNCTION__, hdp->hd_phys_address);
                        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++) {
                        irq = acpi_register_gsi(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) {
                printk("%s: no address or irqs in _CRS\n", __FUNCTION__);
                return -ENODEV;
        }
 
        return hpet_alloc(&data);
}
 
static int hpet_acpi_remove(struct acpi_device *device, int type)
{
        /* XXX need to unregister clocksource, dealloc mem, etc */
        return -EINVAL;
}
 
static const struct acpi_device_id hpet_device_ids[] = {
        {"PNP0103", 0},
        {"", 0},
};
MODULE_DEVICE_TABLE(acpi, hpet_device_ids);
 
static struct acpi_driver hpet_acpi_driver = {
        .name = "hpet",
        .ids = hpet_device_ids,
        .ops = {
                .add = hpet_acpi_add,
                .remove = hpet_acpi_remove,
                },
};
 
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_table(dev_root);
 
        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;
}
 
static void __exit hpet_exit(void)
{
        acpi_bus_unregister_driver(&hpet_acpi_driver);
 
        if (sysctl_header)
                unregister_sysctl_table(sysctl_header);
        misc_deregister(&hpet_misc);
 
        return;
}
 
module_init(hpet_init);
module_exit(hpet_exit);
MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
MODULE_LICENSE("GPL");
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[/] [test_project/] [trunk/] [linux_sd_driver/] [drivers/] [char/] [hpet.c] - Blame information for rev 62

Line No.	Rev	Author	Line
1	62	marcus.erl	`/*`
2			`* Intel & MS High Precision Event Timer Implementation.`
3			`*`
4			`* Copyright (C) 2003 Intel Corporation`
5			`* Venki Pallipadi`
6			`* (c) Copyright 2004 Hewlett-Packard Development Company, L.P.`
7			`* Bob Picco <robert.picco@hp.com>`
8			`*`
9			`* This program is free software; you can redistribute it and/or modify`
10			`* it under the terms of the GNU General Public License version 2 as`
11			`* published by the Free Software Foundation.`
12			`*/`
13
14			`#include <linux/interrupt.h>`
15			`#include <linux/module.h>`
16			`#include <linux/kernel.h>`
17			`#include <linux/types.h>`
18			`#include <linux/miscdevice.h>`
19			`#include <linux/major.h>`
20			`#include <linux/ioport.h>`
21			`#include <linux/fcntl.h>`
22			`#include <linux/init.h>`
23			`#include <linux/poll.h>`
24			`#include <linux/mm.h>`
25			`#include <linux/proc_fs.h>`
26			`#include <linux/spinlock.h>`
27			`#include <linux/sysctl.h>`
28			`#include <linux/wait.h>`
29			`#include <linux/bcd.h>`
30			`#include <linux/seq_file.h>`
31			`#include <linux/bitops.h>`
32			`#include <linux/clocksource.h>`
33
34			`#include <asm/current.h>`
35			`#include <asm/uaccess.h>`
36			`#include <asm/system.h>`
37			`#include <asm/io.h>`
38			`#include <asm/irq.h>`
39			`#include <asm/div64.h>`
40