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Diffstat (limited to 'sound/pci/ctxfi/cttimer.c')
-rw-r--r--sound/pci/ctxfi/cttimer.c443
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);
+}
+