This diff simplifies the code that reads the DMA pointer and calls
the audio(4) driver accordingly.
- use simpler (and less) data structures, which makes the code
shorter.
- if multiple interrupts are missed, call audio(4) as many times as
we missed interrupts (unless the pointer wrapped, which this is
undetectable, but upper layer handles it)
- fetch the link fifos size in the interrupt handler, as, according
to the spec it may change dynamically (i haven't seen such a
device yet, but this costs nothing).
- Certain devices expose the last offset of the link fifo size
instead of the fifo size itself, in this case audio(4) stays
one block off (i.e. we don't recover completely from missed
interrupts). Fix this by incrementing the reported link fifo
size if it's odd.
OK?
Index: azalia.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/azalia.c,v
retrieving revision 1.221
diff -u -p -u -p -r1.221 azalia.c
--- azalia.c 11 May 2015 06:46:21 -0000 1.221
+++ azalia.c 28 Jul 2015 07:36:45 -0000
@@ -123,11 +123,7 @@ typedef struct {
int bufsize;
uint16_t fmt;
int blk;
- int nblks; /* # of blocks in the buffer */
- u_long swpos; /* position in the audio(4) layer */
- u_int last_hwpos; /* last known lpib */
- u_long hw_base; /* this + lpib = overall position */
- u_int pos_offs; /* hardware fifo space */
+ unsigned int swpos; /* position in the audio(4) layer */
} stream_t;
#define STR_READ_1(s, r) \
bus_space_read_1((s)->az->iot, (s)->az->ioh, (s)->regbase + HDA_SD_##r)
@@ -3672,7 +3668,6 @@ azalia_stream_init(stream_t *this, azali
this->intr_bit = 1 << regindex;
this->number = strnum;
this->dir = dir;
- this->pos_offs = STR_READ_2(this, FIFOS) & 0xff;
/* setup BDL buffers */
err = azalia_alloc_dmamem(az, sizeof(bdlist_entry_t) * HDA_BDL_MAX,
@@ -3764,7 +3759,6 @@ azalia_stream_start(stream_t *this)
break;
}
}
- this->nblks = index;
DPRINTFN(1, ("%s: size=%d fmt=0x%4.4x index=%d\n",
__func__, this->bufsize, this->fmt, index));
@@ -3813,7 +3807,7 @@ azalia_stream_halt(stream_t *this)
int
azalia_stream_intr(stream_t *this)
{
- u_long hwpos, swpos;
+ unsigned int lpib, fifos, hwpos, cnt;
u_int8_t sts;
sts = STR_READ_1(this, STS);
@@ -3825,31 +3819,30 @@ azalia_stream_intr(stream_t *this)
this->number, sts, HDA_SD_STS_BITS));
if (sts & HDA_SD_STS_BCIS) {
- hwpos = STR_READ_4(this, LPIB) + this->pos_offs;
- if (hwpos < this->last_hwpos)
- this->hw_base += this->blk * this->nblks;
- this->last_hwpos = hwpos;
- hwpos += this->hw_base;
-
- /*
- * We got the interrupt, so we should advance our count.
- * But we might *not* advance the count if software is
- * ahead.
- */
- swpos = this->swpos + this->blk;
-
- if (hwpos >= swpos + this->blk) {
- DPRINTF(("%s: stream %d: swpos %lu hwpos %lu, adding
intr\n",
- __func__, this->number, swpos, hwpos));
+ lpib = STR_READ_4(this, LPIB);
+ fifos = STR_READ_2(this, FIFOS);
+ if (fifos & 1)
+ fifos++;
+ hwpos = lpib;
+ if (this->dir == AUMODE_PLAY)
+ hwpos += fifos + 1;
+ if (hwpos >= this->bufsize)
+ hwpos -= this->bufsize;
+ DPRINTFN(2, ("%s: stream %d, pos = %d -> %d, "
+ "lpib = %u, fifos = %u\n", __func__,
+ this->number, this->swpos, hwpos, lpib, fifos));
+ cnt = 0;
+ while (hwpos - this->swpos >= this->blk) {
this->intr(this->intr_arg);
this->swpos += this->blk;
- } else if (swpos >= hwpos + this->blk) {
- DPRINTF(("%s: stream %d: swpos %lu hwpos %lu, ignoring
intr\n",
- __func__, this->number, swpos, hwpos));
- return (1);
+ if (this->swpos == this->bufsize)
+ this->swpos = 0;
+ cnt++;
+ }
+ if (cnt != 1) {
+ DPRINTF(("%s: stream %d: hwpos %u, %u intrs\n",
+ __func__, this->number, this->swpos, cnt));
}
- this->intr(this->intr_arg);
- this->swpos += this->blk;
}
return (1);
}
@@ -4233,10 +4226,7 @@ azalia_trigger_output(void *v, void *sta
az->pstream.fmt = fmt;
az->pstream.intr = intr;
az->pstream.intr_arg = arg;
-
az->pstream.swpos = 0;
- az->pstream.last_hwpos = 0;
- az->pstream.hw_base = 0;
return azalia_stream_start(&az->pstream);
}
@@ -4269,10 +4259,7 @@ azalia_trigger_input(void *v, void *star
az->rstream.fmt = fmt;
az->rstream.intr = intr;
az->rstream.intr_arg = arg;
-
az->rstream.swpos = 0;
- az->rstream.last_hwpos = 0;
- az->rstream.hw_base = 0;
return azalia_stream_start(&az->rstream);
}
