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x86: get irq for hpet timer 

HPET timer's IRQ is 0 by default. So we have to select which irq
will be used by these timers. We wait to set the timer's irq until
we really open it in order to reduce the chance of conflicting with
other device.

Signed-off-by: Kevin Hao <kexin.hao@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Kevin Hao 2008-05-29 18:41:04 +08:00 committed by Ingo Molnar
parent e490517a03
commit 70ef6d595b
2 changed files with 65 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

63
drivers/char/hpet.c
View File

@ -184,6 +184,67 @@ static irqreturn_t hpet_interrupt(int irq, void *data)
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 (irq = find_first_bit(&v, HPET_MAX_IRQ); irq < HPET_MAX_IRQ;
irq = find_next_bit(&v, HPET_MAX_IRQ, 1 + irq)) {
if (irq >= NR_IRQS) {
irq = HPET_MAX_IRQ;
break;
}
gsi = acpi_register_gsi(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;
@ -215,6 +276,8 @@ static int hpet_open(struct inode *inode, struct file *file)
devp->hd_flags |= HPET_OPEN;
spin_unlock_irq(&hpet_lock);
hpet_timer_set_irq(devp);
return 0;
}

3
include/linux/hpet.h
View File

@ -37,6 +37,7 @@ struct hpet {
#define hpet_compare _u1._hpet_compare
#define HPET_MAX_TIMERS (32)
#define HPET_MAX_IRQ (32)
/*
* HPET general capabilities register
@ -64,7 +65,7 @@ struct hpet {
*/
#define Tn_INT_ROUTE_CAP_MASK (0xffffffff00000000ULL)
#define Tn_INI_ROUTE_CAP_SHIFT (32UL)
#define Tn_INT_ROUTE_CAP_SHIFT (32UL)
#define Tn_FSB_INT_DELCAP_MASK (0x8000UL)
#define Tn_FSB_INT_DELCAP_SHIFT (15)
#define Tn_FSB_EN_CNF_MASK (0x4000UL)