diff options
| author | Balaji Rao <balajirrao@gmail.com> | 2008-01-30 13:30:03 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:30:03 +0100 |
| commit | e3f37a54f690d3e64995ea7ecea08c5ab3070faf (patch) | |
| tree | 1d9d62d95b747ef47cdf994357bd9a41d02889a3 /drivers/char/hpet.c | |
| parent | 45fe4fe19120a22f7339f5bb110447170c25fca9 (diff) | |
| download | lwn-e3f37a54f690d3e64995ea7ecea08c5ab3070faf.tar.gz lwn-e3f37a54f690d3e64995ea7ecea08c5ab3070faf.zip | |
x86: assign IRQs to HPET timers
The userspace API for the HPET (see Documentation/hpet.txt) did not work. The
HPET_IE_ON ioctl was failing as there was no IRQ assigned to the timer
device. This patch fixes it by allocating IRQs to timer blocks in the HPET.
arch/x86/kernel/hpet.c | 13 +++++--------
drivers/char/hpet.c | 45 ++++++++++++++++++++++++++++++++++++++-------
include/linux/hpet.h | 2 +-
3 files changed, 44 insertions(+), 16 deletions(-)
Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'drivers/char/hpet.c')
| -rw-r--r-- | drivers/char/hpet.c | 45 |
1 files changed, 38 insertions, 7 deletions
diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c index 4c16778e3f84..593b32cfbc33 100644 --- a/drivers/char/hpet.c +++ b/drivers/char/hpet.c @@ -806,14 +806,14 @@ static unsigned long hpet_calibrate(struct hpets *hpetp) int hpet_alloc(struct hpet_data *hdp) { - u64 cap, mcfg; + u64 cap, mcfg, hpet_config; struct hpet_dev *devp; - u32 i, ntimer; + u32 i, ntimer, irq; struct hpets *hpetp; size_t siz; struct hpet __iomem *hpet; static struct hpets *last = NULL; - unsigned long period; + unsigned long period, irq_bitmap; unsigned long long temp; /* @@ -840,11 +840,41 @@ int hpet_alloc(struct hpet_data *hdp) hpetp->hp_hpet_phys = hdp->hd_phys_address; hpetp->hp_ntimer = hdp->hd_nirqs; + hpet = hpetp->hp_hpet; - for (i = 0; i < hdp->hd_nirqs; i++) - hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i]; + /* Assign IRQs statically for legacy devices */ + hpetp->hp_dev[0].hd_hdwirq = hdp->hd_irq[0]; + hpetp->hp_dev[1].hd_hdwirq = hdp->hd_irq[1]; - hpet = hpetp->hp_hpet; + /* Assign IRQs dynamically for the others */ + for (i = 2, devp = &hpetp->hp_dev[2]; i < hdp->hd_nirqs; i++, devp++) { + struct hpet_timer __iomem *timer; + + timer = &hpet->hpet_timers[devp - hpetp->hp_dev]; + + hpet_config = readq(&timer->hpet_config); + irq_bitmap = (hpet_config & Tn_INT_ROUTE_CAP_MASK) + >> Tn_INT_ROUTE_CAP_SHIFT; + if (!irq_bitmap) + irq = 0; /* No valid IRQ Assignable */ + else { + irq = find_first_bit(&irq_bitmap, 32); + do { + hpet_config |= irq << Tn_INT_ROUTE_CNF_SHIFT; + writeq(hpet_config, &timer->hpet_config); + + /* + * Verify whether we have written a valid + * IRQ number by reading it back again + */ + hpet_config = readq(&timer->hpet_config); + if (irq == (hpet_config & Tn_INT_ROUTE_CNF_MASK) + >> Tn_INT_ROUTE_CNF_SHIFT) + break; /* Success */ + } while ((irq = (find_next_bit(&irq_bitmap, 32, irq)))); + } + hpetp->hp_dev[i].hd_hdwirq = irq; + } cap = readq(&hpet->hpet_cap); @@ -875,7 +905,8 @@ int hpet_alloc(struct hpet_data *hdp) 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("%s %d", i > 0 ? "," : "", + hpetp->hp_dev[i].hd_hdwirq); printk("\n"); printk(KERN_INFO "hpet%u: %u %d-bit timers, %Lu Hz\n", |