diff options
Diffstat (limited to 'drivers/char/hpet.c')
| -rw-r--r-- | drivers/char/hpet.c | 994 |
1 files changed, 994 insertions, 0 deletions
diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c new file mode 100644 index 00000000000..5ec732e6ca9 --- /dev/null +++ b/drivers/char/hpet.c @@ -0,0 +1,994 @@ +/* + * 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/config.h> +#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/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 <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/labs/platcomp/hpet/hpetspec.htm + */ +#define HPET_USER_FREQ (64) +#define HPET_DRIFT (500) + +static u32 hpet_ntimer, hpet_nhpet, hpet_max_freq = HPET_USER_FREQ; + +/* 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 time_interpolator *hp_interpolator; + unsigned long hp_period; + 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 + +#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 + +#ifndef readq +static unsigned long long __inline readq(void __iomem *addr) +{ + return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL); +} +#endif + +#ifndef writeq +static void __inline 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 pt_regs *regs) +{ + struct hpet_dev *devp; + unsigned long isr; + + devp = data; + + 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); + } + + isr = (1 << (devp - devp->hd_hpets->hp_dev)); + writeq(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); + addr = __pa(addr); + + if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT, + PAGE_SIZE, vma->vm_page_prot)) { + printk(KERN_ERR "remap_pfn_range failed in hpet.c\n"); + 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; + + v = readq(&timer->hpet_config); + spin_lock_irq(&hpet_lock); + + if (devp->hd_flags & HPET_IE) { + spin_unlock_irq(&hpet_lock); + return -EBUSY; + } + + devp->hd_flags |= HPET_IE; + spin_unlock_irq(&hpet_lock); + + t = readq(&timer->hpet_config); + irq = devp->hd_hdwirq; + + if (irq) { + sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev)); + + if (request_irq + (irq, hpet_interrupt, SA_INTERRUPT, 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); + } + + isr = (1 << (devp - hpets->hp_dev)); + writeq(isr, &hpet->hpet_isr); + writeq(g, &timer->hpet_config); + local_irq_restore(flags); + + return 0; +} + +static inline unsigned long hpet_time_div(unsigned long dis) +{ + unsigned long long m = 1000000000000000ULL; + + 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; + + info.hi_ireqfreq = hpet_time_div(hpetp->hp_period * + devp->hd_ireqfreq); + info.hi_flags = + readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK; + info.hi_hpet = devp->hd_hpets->hp_which; + info.hi_timer = devp - devp->hd_hpets->hp_dev; + 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 & (arg - 1)) { + err = -EINVAL; + break; + } + + devp->hd_ireqfreq = hpet_time_div(hpetp->hp_period * arg); + } + + return err; +} + +static 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, +}; + +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; + } + + 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 = 1, + .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 = 1, + .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; + +static void hpet_register_interpolator(struct hpets *hpetp) +{ +#ifdef CONFIG_TIME_INTERPOLATION + struct time_interpolator *ti; + + ti = kmalloc(sizeof(*ti), GFP_KERNEL); + if (!ti) + return; + + memset(ti, 0, sizeof(*ti)); + ti->source = TIME_SOURCE_MMIO64; + ti->shift = 10; + ti->addr = &hpetp->hp_hpet->hpet_mc; + ti->frequency = hpet_time_div(hpets->hp_period); + ti->drift = ti->frequency * HPET_DRIFT / 1000000; + ti->mask = -1; + + hpetp->hp_interpolator = ti; + register_time_interpolator(ti); +#endif +} + +/* + * 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 = hpets->hp_hpet; + t = read_counter(&timer->hpet_compare); + + i = 0; + count = hpet_time_div(hpetp->hp_period * 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 = (struct hpets *)0; + unsigned long ns; + + /* + * hpet_alloc can be called by platform dependent code. + * if platform dependent code has allocated the hpet + * ACPI also reports hpet, then we catch it here. + */ + for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next) + if (hpetp->hp_hpet == hdp->hd_address) + return 0; + + siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) * + sizeof(struct hpet_dev)); + + hpetp = kmalloc(siz, GFP_KERNEL); + + if (!hpetp) + return -ENOMEM; + + memset(hpetp, 0, siz); + + 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; + + hpetp->hp_period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >> + HPET_COUNTER_CLK_PERIOD_SHIFT; + + 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"); + + ns = hpetp->hp_period; /* femptoseconds, 10^-15 */ + do_div(ns, 1000000); /* convert to nanoseconds, 10^-9 */ + printk(KERN_INFO "hpet%d: %ldns tick, %d %d-bit timers\n", + hpetp->hp_which, ns, hpetp->hp_ntimer, + cap & HPET_COUNTER_SIZE_MASK ? 64 : 32); + + 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++, hpet_ntimer++, devp++) { + unsigned long v; + struct hpet_timer __iomem *timer; + + timer = &hpet->hpet_timers[devp - hpetp->hp_dev]; + v = readq(&timer->hpet_config); + + 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); + hpet_register_interpolator(hpetp); + + 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; + struct hpets *hpetp; + + hdp = data; + + status = acpi_resource_to_address64(res, &addr); + + if (ACPI_SUCCESS(status)) { + unsigned long size; + + size = addr.max_address_range - addr.min_address_range + 1; + hdp->hd_phys_address = addr.min_address_range; + hdp->hd_address = ioremap(addr.min_address_range, size); + + for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next) + if (hpetp->hp_hpet == hdp->hd_address) + return -EBUSY; + } else if (res->id == ACPI_RSTYPE_EXT_IRQ) { + struct acpi_resource_ext_irq *irqp; + int i; + + irqp = &res->data.extended_irq; + + if (irqp->number_of_interrupts > 0) { + hdp->hd_nirqs = irqp->number_of_interrupts; + + for (i = 0; i < hdp->hd_nirqs; i++) + hdp->hd_irq[i] = + acpi_register_gsi(irqp->interrupts[i], + irqp->edge_level, + irqp->active_high_low); + } + } + + 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 interpolator, dealloc mem, etc */ + return -EINVAL; +} + +static struct acpi_driver hpet_acpi_driver = { + .name = "hpet", + .ids = "PNP0103", + .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, 0); + + 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"); |