linux/drivers/char/hpet.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

1034 lines
22 KiB
C

/*
* 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/smp_lock.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 <linux/slab.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_1.pdf
*/
#define HPET_USER_FREQ (64)
#define HPET_DRIFT (500)
#define HPET_RANGE_SIZE 1024 /* from HPET spec */
/* WARNING -- don't get confused. These macros are never used
* to write the (single) counter, and rarely to read it.
* They're badly named; to fix, someday.
*/
#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(struct clocksource *cs)
{
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 calculated */
.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);
#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;
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_timer->hpet_compare);
write_counter(t + m, &devp->hd_timer->hpet_compare);
}
if (devp->hd_flags & HPET_SHARED_IRQ)
writel(isr, &devp->hd_hpet->hpet_isr);
spin_unlock(&hpet_lock);
wake_up_interruptible(&devp->hd_waitqueue);
kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
return IRQ_HANDLED;
}
static void hpet_timer_set_irq(struct hpet_dev *devp)
{
unsigned long v;
int irq, gsi;
struct hpet_timer __iomem *timer;
spin_lock_irq(&hpet_lock);
if (devp->hd_hdwirq) {
spin_unlock_irq(&hpet_lock);
return;
}
timer = devp->hd_timer;
/* we prefer level triggered mode */
v = readl(&timer->hpet_config);
if (!(v & Tn_INT_TYPE_CNF_MASK)) {
v |= Tn_INT_TYPE_CNF_MASK;
writel(v, &timer->hpet_config);
}
spin_unlock_irq(&hpet_lock);
v = (readq(&timer->hpet_config) & Tn_INT_ROUTE_CAP_MASK) >>
Tn_INT_ROUTE_CAP_SHIFT;
/*
* In PIC mode, skip IRQ0-4, IRQ6-9, IRQ12-15 which is always used by
* legacy device. In IO APIC mode, we skip all the legacy IRQS.
*/
if (acpi_irq_model == ACPI_IRQ_MODEL_PIC)
v &= ~0xf3df;
else
v &= ~0xffff;
for_each_set_bit(irq, &v, HPET_MAX_IRQ) {
if (irq >= nr_irqs) {
irq = HPET_MAX_IRQ;
break;
}
gsi = acpi_register_gsi(NULL, irq, ACPI_LEVEL_SENSITIVE,
ACPI_ACTIVE_LOW);
if (gsi > 0)
break;
/* FIXME: Setup interrupt source table */
}
if (irq < HPET_MAX_IRQ) {
spin_lock_irq(&hpet_lock);
v = readl(&timer->hpet_config);
v |= irq << Tn_INT_ROUTE_CNF_SHIFT;
writel(v, &timer->hpet_config);
devp->hd_hdwirq = gsi;
spin_unlock_irq(&hpet_lock);
}
return;
}
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;
lock_kernel();
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)
continue;
else {
devp = &hpetp->hp_dev[i];
break;
}
if (!devp) {
spin_unlock_irq(&hpet_lock);
unlock_kernel();
return -EBUSY;
}
file->private_data = devp;
devp->hd_irqdata = 0;
devp->hd_flags |= HPET_OPEN;
spin_unlock_irq(&hpet_lock);
unlock_kernel();
hpet_timer_set_irq(devp);
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",
__func__);
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);
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);
/* 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);
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;
}
static ctl_table hpet_table[] = {
{
.procname = "max-user-freq",
.data = &hpet_max_freq,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{}
};
static ctl_table hpet_root[] = {
{
.procname = "hpet",
.maxlen = 0,
.mode = 0555,
.child = hpet_table,
},
{}
};
static ctl_table dev_root[] = {
{
.procname = "dev",
.maxlen = 0,
.mode = 0555,
.child = hpet_root,
},
{}
};
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 = -1;
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;
size_t siz;
struct hpet __iomem *hpet;
static struct hpets *last = NULL;
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;
}
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");
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;
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)) {
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)) {
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(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) {
printk("%s: no address or irqs in _CRS\n", __func__);
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");