aboutsummaryrefslogtreecommitdiff
path: root/drivers/char/hpet.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/char/hpet.c')
-rw-r--r--drivers/char/hpet.c168
1 files changed, 113 insertions, 55 deletions
diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
index c055bb630ff..3808d957261 100644
--- a/drivers/char/hpet.c
+++ b/drivers/char/hpet.c
@@ -49,7 +49,9 @@
#define HPET_USER_FREQ (64)
#define HPET_DRIFT (500)
-static u32 hpet_ntimer, hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
+#define HPET_RANGE_SIZE 1024 /* from HPET spec */
+
+static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
/* A lock for concurrent access by app and isr hpet activity. */
static DEFINE_SPINLOCK(hpet_lock);
@@ -78,7 +80,7 @@ struct hpets {
struct hpet __iomem *hp_hpet;
unsigned long hp_hpet_phys;
struct time_interpolator *hp_interpolator;
- unsigned long hp_period;
+ unsigned long long hp_tick_freq;
unsigned long hp_delta;
unsigned int hp_ntimer;
unsigned int hp_which;
@@ -90,6 +92,7 @@ static struct hpets *hpets;
#define HPET_OPEN 0x0001
#define HPET_IE 0x0002 /* interrupt enabled */
#define HPET_PERIODIC 0x0004
+#define HPET_SHARED_IRQ 0x0008
#if BITS_PER_LONG == 64
#define write_counter(V, MC) writeq(V, MC)
@@ -120,6 +123,11 @@ static irqreturn_t hpet_interrupt(int irq, void *data, struct pt_regs *regs)
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++;
@@ -137,8 +145,8 @@ static irqreturn_t hpet_interrupt(int irq, void *data, struct pt_regs *regs)
&devp->hd_timer->hpet_compare);
}
- isr = (1 << (devp - devp->hd_hpets->hp_dev));
- writeq(isr, &devp->hd_hpet->hpet_isr);
+ if (devp->hd_flags & HPET_SHARED_IRQ)
+ writel(isr, &devp->hd_hpet->hpet_isr);
spin_unlock(&hpet_lock);
spin_lock(&hpet_task_lock);
@@ -276,7 +284,8 @@ static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
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");
+ printk(KERN_ERR "%s: io_remap_pfn_range failed\n",
+ __FUNCTION__);
return -EAGAIN;
}
@@ -364,7 +373,9 @@ static int hpet_ioctl_ieon(struct hpet_dev *devp)
hpet = devp->hd_hpet;
hpetp = devp->hd_hpets;
- v = readq(&timer->hpet_config);
+ if (!devp->hd_ireqfreq)
+ return -EIO;
+
spin_lock_irq(&hpet_lock);
if (devp->hd_flags & HPET_IE) {
@@ -373,16 +384,21 @@ static int hpet_ioctl_ieon(struct hpet_dev *devp)
}
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);
- t = readq(&timer->hpet_config);
irq = devp->hd_hdwirq;
if (irq) {
- sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
+ unsigned long irq_flags;
- if (request_irq
- (irq, hpet_interrupt, SA_INTERRUPT, devp->hd_name, (void *)devp)) {
+ sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
+ irq_flags = devp->hd_flags & HPET_SHARED_IRQ
+ ? SA_SHIRQ : SA_INTERRUPT;
+ 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;
}
@@ -416,20 +432,24 @@ static int hpet_ioctl_ieon(struct hpet_dev *devp)
write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
}
- isr = (1 << (devp - hpets->hp_dev));
- writeq(isr, &hpet->hpet_isr);
+ 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;
}
-static inline unsigned long hpet_time_div(unsigned long dis)
+/* converts Hz to number of timer ticks */
+static inline unsigned long hpet_time_div(struct hpets *hpets,
+ unsigned long dis)
{
- unsigned long long m = 1000000000000000ULL;
+ unsigned long long m;
+ m = hpets->hp_tick_freq + (dis >> 1);
do_div(m, dis);
-
return (unsigned long)m;
}
@@ -477,14 +497,21 @@ hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel)
{
struct hpet_info info;
- info.hi_ireqfreq = hpet_time_div(hpetp->hp_period *
- devp->hd_ireqfreq);
+ 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 = 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;
+ 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:
@@ -516,12 +543,12 @@ hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel)
break;
}
- if (arg & (arg - 1)) {
+ if (!arg) {
err = -EINVAL;
break;
}
- devp->hd_ireqfreq = hpet_time_div(hpetp->hp_period * arg);
+ devp->hd_ireqfreq = hpet_time_div(hpetp, arg);
}
return err;
@@ -539,6 +566,17 @@ static struct file_operations hpet_fops = {
.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);
@@ -563,6 +601,8 @@ int hpet_register(struct hpet_task *tp, int periodic)
return -EINVAL;
}
+ tp->ht_opaque = NULL;
+
spin_lock_irq(&hpet_task_lock);
spin_lock(&hpet_lock);
@@ -702,15 +742,14 @@ static void hpet_register_interpolator(struct hpets *hpetp)
#ifdef CONFIG_TIME_INTERPOLATION
struct time_interpolator *ti;
- ti = kmalloc(sizeof(*ti), GFP_KERNEL);
+ ti = kzalloc(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->frequency = hpetp->hp_tick_freq;
ti->drift = HPET_DRIFT;
ti->mask = -1;
@@ -743,11 +782,11 @@ static unsigned long hpet_calibrate(struct hpets *hpetp)
if (!timer)
return 0;
- hpet = hpets->hp_hpet;
+ hpet = hpetp->hp_hpet;
t = read_counter(&timer->hpet_compare);
i = 0;
- count = hpet_time_div(hpetp->hp_period * TICK_CALIBRATE);
+ count = hpet_time_div(hpetp, TICK_CALIBRATE);
local_irq_save(flags);
@@ -771,28 +810,29 @@ int hpet_alloc(struct hpet_data *hdp)
struct hpets *hpetp;
size_t siz;
struct hpet __iomem *hpet;
- static struct hpets *last = (struct hpets *)0;
- unsigned long ns;
+ 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
- * ACPI also reports hpet, then we catch it here.
+ * If platform dependent code has allocated the hpet that
+ * ACPI has also reported, then we catch it here.
*/
- for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
- if (hpetp->hp_hpet == hdp->hd_address)
- return 0;
+ 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 = kmalloc(siz, GFP_KERNEL);
+ hpetp = kzalloc(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;
@@ -822,21 +862,23 @@ int hpet_alloc(struct hpet_data *hdp)
last = hpetp;
- hpetp->hp_period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
- HPET_COUNTER_CLK_PERIOD_SHIFT;
+ 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,
+ printk(KERN_INFO "hpet%d: at MMIO 0x%lx (virtual 0x%p), IRQ%s",
+ hpetp->hp_which, hdp->hd_phys_address, hdp->hd_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 */
- 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);
+ 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) {
@@ -845,13 +887,10 @@ int hpet_alloc(struct hpet_data *hdp)
writeq(mcfg, &hpet->hpet_config);
}
- for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer;
- i++, hpet_ntimer++, devp++) {
- unsigned long v;
+ 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];
- v = readq(&timer->hpet_config);
devp->hd_hpets = hpetp;
devp->hd_hpet = hpet;
@@ -880,7 +919,6 @@ 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;
@@ -893,9 +931,29 @@ static acpi_status hpet_resources(struct acpi_resource *res, void *data)
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;
+ if (hpet_is_known(hdp)) {
+ printk(KERN_DEBUG "%s: 0x%lx is busy\n",
+ __FUNCTION__, hdp->hd_phys_address);
+ iounmap(hdp->hd_address);
+ return -EBUSY;
+ }
+ } else if (res->id == ACPI_RSTYPE_FIXED_MEM32) {
+ struct acpi_resource_fixed_mem32 *fixmem32;
+
+ fixmem32 = &res->data.fixed_memory32;
+ if (!fixmem32)
+ return -EINVAL;
+
+ hdp->hd_phys_address = fixmem32->range_base_address;
+ hdp->hd_address = ioremap(fixmem32->range_base_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 -EBUSY;
+ }
} else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
struct acpi_resource_ext_irq *irqp;
int i;