diff options
Diffstat (limited to 'sound/pci/ctxfi/cttimer.c')
| -rw-r--r-- | sound/pci/ctxfi/cttimer.c | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/sound/pci/ctxfi/cttimer.c b/sound/pci/ctxfi/cttimer.c new file mode 100644 index 000000000..a5d460453 --- /dev/null +++ b/sound/pci/ctxfi/cttimer.c @@ -0,0 +1,443 @@ +/* + * PCM timer handling on ctxfi + * + * This source file is released under GPL v2 license (no other versions). + * See the COPYING file included in the main directory of this source + * distribution for the license terms and conditions. + */ + +#include <linux/slab.h> +#include <linux/math64.h> +#include <linux/moduleparam.h> +#include <sound/core.h> +#include <sound/pcm.h> +#include "ctatc.h" +#include "cthardware.h" +#include "cttimer.h" + +static bool use_system_timer; +MODULE_PARM_DESC(use_system_timer, "Force to use system-timer"); +module_param(use_system_timer, bool, S_IRUGO); + +struct ct_timer_ops { + void (*init)(struct ct_timer_instance *); + void (*prepare)(struct ct_timer_instance *); + void (*start)(struct ct_timer_instance *); + void (*stop)(struct ct_timer_instance *); + void (*free_instance)(struct ct_timer_instance *); + void (*interrupt)(struct ct_timer *); + void (*free_global)(struct ct_timer *); +}; + +/* timer instance -- assigned to each PCM stream */ +struct ct_timer_instance { + spinlock_t lock; + struct ct_timer *timer_base; + struct ct_atc_pcm *apcm; + struct snd_pcm_substream *substream; + struct timer_list timer; + struct list_head instance_list; + struct list_head running_list; + unsigned int position; + unsigned int frag_count; + unsigned int running:1; + unsigned int need_update:1; +}; + +/* timer instance manager */ +struct ct_timer { + spinlock_t lock; /* global timer lock (for xfitimer) */ + spinlock_t list_lock; /* lock for instance list */ + struct ct_atc *atc; + struct ct_timer_ops *ops; + struct list_head instance_head; + struct list_head running_head; + unsigned int wc; /* current wallclock */ + unsigned int irq_handling:1; /* in IRQ handling */ + unsigned int reprogram:1; /* need to reprogram the internval */ + unsigned int running:1; /* global timer running */ +}; + + +/* + * system-timer-based updates + */ + +static void ct_systimer_callback(unsigned long data) +{ + struct ct_timer_instance *ti = (struct ct_timer_instance *)data; + struct snd_pcm_substream *substream = ti->substream; + struct snd_pcm_runtime *runtime = substream->runtime; + struct ct_atc_pcm *apcm = ti->apcm; + unsigned int period_size = runtime->period_size; + unsigned int buffer_size = runtime->buffer_size; + unsigned long flags; + unsigned int position, dist, interval; + + position = substream->ops->pointer(substream); + dist = (position + buffer_size - ti->position) % buffer_size; + if (dist >= period_size || + position / period_size != ti->position / period_size) { + apcm->interrupt(apcm); + ti->position = position; + } + /* Add extra HZ*5/1000 to avoid overrun issue when recording + * at 8kHz in 8-bit format or at 88kHz in 24-bit format. */ + interval = ((period_size - (position % period_size)) + * HZ + (runtime->rate - 1)) / runtime->rate + HZ * 5 / 1000; + spin_lock_irqsave(&ti->lock, flags); + if (ti->running) + mod_timer(&ti->timer, jiffies + interval); + spin_unlock_irqrestore(&ti->lock, flags); +} + +static void ct_systimer_init(struct ct_timer_instance *ti) +{ + setup_timer(&ti->timer, ct_systimer_callback, + (unsigned long)ti); +} + +static void ct_systimer_start(struct ct_timer_instance *ti) +{ + struct snd_pcm_runtime *runtime = ti->substream->runtime; + unsigned long flags; + + spin_lock_irqsave(&ti->lock, flags); + ti->running = 1; + mod_timer(&ti->timer, + jiffies + (runtime->period_size * HZ + + (runtime->rate - 1)) / runtime->rate); + spin_unlock_irqrestore(&ti->lock, flags); +} + +static void ct_systimer_stop(struct ct_timer_instance *ti) +{ + unsigned long flags; + + spin_lock_irqsave(&ti->lock, flags); + ti->running = 0; + del_timer(&ti->timer); + spin_unlock_irqrestore(&ti->lock, flags); +} + +static void ct_systimer_prepare(struct ct_timer_instance *ti) +{ + ct_systimer_stop(ti); + try_to_del_timer_sync(&ti->timer); +} + +#define ct_systimer_free ct_systimer_prepare + +static struct ct_timer_ops ct_systimer_ops = { + .init = ct_systimer_init, + .free_instance = ct_systimer_free, + .prepare = ct_systimer_prepare, + .start = ct_systimer_start, + .stop = ct_systimer_stop, +}; + + +/* + * Handling multiple streams using a global emu20k1 timer irq + */ + +#define CT_TIMER_FREQ 48000 +#define MIN_TICKS 1 +#define MAX_TICKS ((1 << 13) - 1) + +static void ct_xfitimer_irq_rearm(struct ct_timer *atimer, int ticks) +{ + struct hw *hw = atimer->atc->hw; + if (ticks > MAX_TICKS) + ticks = MAX_TICKS; + hw->set_timer_tick(hw, ticks); + if (!atimer->running) + hw->set_timer_irq(hw, 1); + atimer->running = 1; +} + +static void ct_xfitimer_irq_stop(struct ct_timer *atimer) +{ + if (atimer->running) { + struct hw *hw = atimer->atc->hw; + hw->set_timer_irq(hw, 0); + hw->set_timer_tick(hw, 0); + atimer->running = 0; + } +} + +static inline unsigned int ct_xfitimer_get_wc(struct ct_timer *atimer) +{ + struct hw *hw = atimer->atc->hw; + return hw->get_wc(hw); +} + +/* + * reprogram the timer interval; + * checks the running instance list and determines the next timer interval. + * also updates the each stream position, returns the number of streams + * to call snd_pcm_period_elapsed() appropriately + * + * call this inside the lock and irq disabled + */ +static int ct_xfitimer_reprogram(struct ct_timer *atimer, int can_update) +{ + struct ct_timer_instance *ti; + unsigned int min_intr = (unsigned int)-1; + int updates = 0; + unsigned int wc, diff; + + if (list_empty(&atimer->running_head)) { + ct_xfitimer_irq_stop(atimer); + atimer->reprogram = 0; /* clear flag */ + return 0; + } + + wc = ct_xfitimer_get_wc(atimer); + diff = wc - atimer->wc; + atimer->wc = wc; + list_for_each_entry(ti, &atimer->running_head, running_list) { + if (ti->frag_count > diff) + ti->frag_count -= diff; + else { + unsigned int pos; + unsigned int period_size, rate; + + period_size = ti->substream->runtime->period_size; + rate = ti->substream->runtime->rate; + pos = ti->substream->ops->pointer(ti->substream); + if (pos / period_size != ti->position / period_size) { + ti->need_update = 1; + ti->position = pos; + updates++; + } + pos %= period_size; + pos = period_size - pos; + ti->frag_count = div_u64((u64)pos * CT_TIMER_FREQ + + rate - 1, rate); + } + if (ti->need_update && !can_update) + min_intr = 0; /* pending to the next irq */ + if (ti->frag_count < min_intr) + min_intr = ti->frag_count; + } + + if (min_intr < MIN_TICKS) + min_intr = MIN_TICKS; + ct_xfitimer_irq_rearm(atimer, min_intr); + atimer->reprogram = 0; /* clear flag */ + return updates; +} + +/* look through the instance list and call period_elapsed if needed */ +static void ct_xfitimer_check_period(struct ct_timer *atimer) +{ + struct ct_timer_instance *ti; + unsigned long flags; + + spin_lock_irqsave(&atimer->list_lock, flags); + list_for_each_entry(ti, &atimer->instance_head, instance_list) { + if (ti->running && ti->need_update) { + ti->need_update = 0; + ti->apcm->interrupt(ti->apcm); + } + } + spin_unlock_irqrestore(&atimer->list_lock, flags); +} + +/* Handle timer-interrupt */ +static void ct_xfitimer_callback(struct ct_timer *atimer) +{ + int update; + unsigned long flags; + + spin_lock_irqsave(&atimer->lock, flags); + atimer->irq_handling = 1; + do { + update = ct_xfitimer_reprogram(atimer, 1); + spin_unlock(&atimer->lock); + if (update) + ct_xfitimer_check_period(atimer); + spin_lock(&atimer->lock); + } while (atimer->reprogram); + atimer->irq_handling = 0; + spin_unlock_irqrestore(&atimer->lock, flags); +} + +static void ct_xfitimer_prepare(struct ct_timer_instance *ti) +{ + ti->frag_count = ti->substream->runtime->period_size; + ti->running = 0; + ti->need_update = 0; +} + + +/* start/stop the timer */ +static void ct_xfitimer_update(struct ct_timer *atimer) +{ + unsigned long flags; + + spin_lock_irqsave(&atimer->lock, flags); + if (atimer->irq_handling) { + /* reached from IRQ handler; let it handle later */ + atimer->reprogram = 1; + spin_unlock_irqrestore(&atimer->lock, flags); + return; + } + + ct_xfitimer_irq_stop(atimer); + ct_xfitimer_reprogram(atimer, 0); + spin_unlock_irqrestore(&atimer->lock, flags); +} + +static void ct_xfitimer_start(struct ct_timer_instance *ti) +{ + struct ct_timer *atimer = ti->timer_base; + unsigned long flags; + + spin_lock_irqsave(&atimer->lock, flags); + if (list_empty(&ti->running_list)) + atimer->wc = ct_xfitimer_get_wc(atimer); + ti->running = 1; + ti->need_update = 0; + list_add(&ti->running_list, &atimer->running_head); + spin_unlock_irqrestore(&atimer->lock, flags); + ct_xfitimer_update(atimer); +} + +static void ct_xfitimer_stop(struct ct_timer_instance *ti) +{ + struct ct_timer *atimer = ti->timer_base; + unsigned long flags; + + spin_lock_irqsave(&atimer->lock, flags); + list_del_init(&ti->running_list); + ti->running = 0; + spin_unlock_irqrestore(&atimer->lock, flags); + ct_xfitimer_update(atimer); +} + +static void ct_xfitimer_free_global(struct ct_timer *atimer) +{ + ct_xfitimer_irq_stop(atimer); +} + +static struct ct_timer_ops ct_xfitimer_ops = { + .prepare = ct_xfitimer_prepare, + .start = ct_xfitimer_start, + .stop = ct_xfitimer_stop, + .interrupt = ct_xfitimer_callback, + .free_global = ct_xfitimer_free_global, +}; + +/* + * timer instance + */ + +struct ct_timer_instance * +ct_timer_instance_new(struct ct_timer *atimer, struct ct_atc_pcm *apcm) +{ + struct ct_timer_instance *ti; + + ti = kzalloc(sizeof(*ti), GFP_KERNEL); + if (!ti) + return NULL; + spin_lock_init(&ti->lock); + INIT_LIST_HEAD(&ti->instance_list); + INIT_LIST_HEAD(&ti->running_list); + ti->timer_base = atimer; + ti->apcm = apcm; + ti->substream = apcm->substream; + if (atimer->ops->init) + atimer->ops->init(ti); + + spin_lock_irq(&atimer->list_lock); + list_add(&ti->instance_list, &atimer->instance_head); + spin_unlock_irq(&atimer->list_lock); + + return ti; +} + +void ct_timer_prepare(struct ct_timer_instance *ti) +{ + if (ti->timer_base->ops->prepare) + ti->timer_base->ops->prepare(ti); + ti->position = 0; + ti->running = 0; +} + +void ct_timer_start(struct ct_timer_instance *ti) +{ + struct ct_timer *atimer = ti->timer_base; + atimer->ops->start(ti); +} + +void ct_timer_stop(struct ct_timer_instance *ti) +{ + struct ct_timer *atimer = ti->timer_base; + atimer->ops->stop(ti); +} + +void ct_timer_instance_free(struct ct_timer_instance *ti) +{ + struct ct_timer *atimer = ti->timer_base; + + atimer->ops->stop(ti); /* to be sure */ + if (atimer->ops->free_instance) + atimer->ops->free_instance(ti); + + spin_lock_irq(&atimer->list_lock); + list_del(&ti->instance_list); + spin_unlock_irq(&atimer->list_lock); + + kfree(ti); +} + +/* + * timer manager + */ + +static void ct_timer_interrupt(void *data, unsigned int status) +{ + struct ct_timer *timer = data; + + /* Interval timer interrupt */ + if ((status & IT_INT) && timer->ops->interrupt) + timer->ops->interrupt(timer); +} + +struct ct_timer *ct_timer_new(struct ct_atc *atc) +{ + struct ct_timer *atimer; + struct hw *hw; + + atimer = kzalloc(sizeof(*atimer), GFP_KERNEL); + if (!atimer) + return NULL; + spin_lock_init(&atimer->lock); + spin_lock_init(&atimer->list_lock); + INIT_LIST_HEAD(&atimer->instance_head); + INIT_LIST_HEAD(&atimer->running_head); + atimer->atc = atc; + hw = atc->hw; + if (!use_system_timer && hw->set_timer_irq) { + dev_info(atc->card->dev, "Use xfi-native timer\n"); + atimer->ops = &ct_xfitimer_ops; + hw->irq_callback_data = atimer; + hw->irq_callback = ct_timer_interrupt; + } else { + dev_info(atc->card->dev, "Use system timer\n"); + atimer->ops = &ct_systimer_ops; + } + return atimer; +} + +void ct_timer_free(struct ct_timer *atimer) +{ + struct hw *hw = atimer->atc->hw; + hw->irq_callback = NULL; + if (atimer->ops->free_global) + atimer->ops->free_global(atimer); + kfree(atimer); +} + |