Vergil_Wong/lib_xua
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Made prefill levels vary with sample rate and usb speed

Browse Source
This commit is contained in:
Dave Lacey
2011-04-04 16:52:42 +01:00
committed by Russell
parent 1d0daaa818
commit afc59caf36
1 changed files with 75 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

84
module_usb_aud_shared/usb_buffer/decouple.xc
View File

@@ -58,11 +58,8 @@ inline void XUD_Change_ReadyIn_Buffer(XUD_ep e, unsigned bufferPtr, int len)
#define BUFF_SIZE_OUT MAX(4 * CLASS_TWO_PACKET_SIZE * NUM_USB_CHAN_OUT, 4 * CLASS_ONE_PACKET_SIZE * MAX_CLASS_ONE_CHAN)
#define BUFF_SIZE_IN MAX(4 * CLASS_TWO_PACKET_SIZE * NUM_USB_CHAN_IN, 4 * CLASS_ONE_PACKET_SIZE * MAX_CLASS_ONE_CHAN)
#define MAX_USB_AUD_PACKET_SIZE 1028
//#define OUT_BUFFER_PREFILL (2*4*BUFF_SIZE_OUT/3)
//#define OUT_BUFFER_PREFILL MAX(CLASS_ONE_PACKET_SIZE*3+4,CLASS_TWO_PACKET_SIZE*4+4)*2
//#define IN_BUFFER_PREFILL MAX(CLASS_ONE_PACKET_SIZE*3+4,CLASS_TWO_PACKET_SIZE*4+4)*2
#define OUT_BUFFER_PREFILL (MAX(MAX_CLASS_ONE_CHAN*CLASS_ONE_PACKET_SIZE*3+4,NUM_USB_CHAN_OUT*CLASS_TWO_PACKET_SIZE*4+4)*1)
#define IN_BUFFER_PREFILL (MAX(CLASS_ONE_PACKET_SIZE*3+4,CLASS_TWO_PACKET_SIZE*4+4)*2)
#define NUM_PACKETS_PREFILL (1)
//#pragma xta command "add exclusion out_underflow"
//#pragma xta command "add exclusion freq_change"
//#pragma xta command "add exclusion print_err"is_as
@@ -93,6 +90,9 @@ unsigned audioBuffIn[BUFF_SIZE_IN + (MAX_DEVICE_AUD_PACKET_SIZE>>2) + 4];
unsigned inZeroBuff[(MAX_DEVICE_AUD_PACKET_SIZE>>2)+4];
unsigned g_in_buffer_prefill = 0;
unsigned g_out_buffer_prefill = 0;
unsigned ledVal = 1;
unsigned dir = 0;
@@ -139,6 +139,42 @@ void led(chanend ?c_led)
void GetADCCounts(unsigned samFreq, int &min, int &mid, int &max);
/* This function sets the prefill levels for the in and out buffers,
it needs to be changed for a different sample rate or number of channels.
The amount set here is what determines the latency of the buffering.
*/
static void set_prefills(unsigned int sampFreq) {
int min,mid,max;
int usb_speed;
unsigned prefill;
int bytes_per_sample;
int num_channels;
int frame;
int packet_size;
GET_SHARED_GLOBAL(usb_speed, g_curUsbSpeed);
frame = usb_speed == XUD_SPEED_HS ? 8000 : 1000;
packet_size = ((((sampFreq+frame-1)/frame))+3);
bytes_per_sample = usb_speed == XUD_SPEED_HS ? 4 : 3;
GET_SHARED_GLOBAL(num_channels, g_numUsbChanOut);
prefill = ((packet_size * num_channels * bytes_per_sample + 4) * NUM_PACKETS_PREFILL);
SET_SHARED_GLOBAL(g_out_buffer_prefill, prefill);
GET_SHARED_GLOBAL(num_channels, g_numUsbChanIn);
prefill = ((packet_size * num_channels * bytes_per_sample + 4) * NUM_PACKETS_PREFILL);
SET_SHARED_GLOBAL(g_in_buffer_prefill, prefill);
return;
}
static inline void swap(xc_ptr &a, xc_ptr &b)
{
xc_ptr tmp;
@@ -283,6 +319,15 @@ void handle_audio_request(chanend c_mix_out, chanend ?c_led)
if (space_left > (BUFF_SIZE_IN*4/2))
{
inOverflow = 0;
// When we come out of overflow we clear the buffer and
// go into underflow and do a prefill again - this is to
// get a low latency and to ensure consistency between
// coming out of underflow or overflow
inUnderflow = 1;
SET_SHARED_GLOBAL(g_aud_to_host_rdptr,
aud_to_host_fifo_start);
SET_SHARED_GLOBAL(g_aud_to_host_wrptr,
aud_to_host_fifo_start);
}
}
else
@@ -370,6 +415,7 @@ void handle_audio_request(chanend c_mix_out, chanend ?c_led)
if(outUnderflow)
{
unsigned prefill;
#pragma xta endpoint "out_underflow"
/* We're still pre-buffering, send out 0 samps */
for(int i = 0; i < NUM_USB_CHAN_OUT; i++)
@@ -384,8 +430,9 @@ void handle_audio_request(chanend c_mix_out, chanend ?c_led)
outSamps += BUFF_SIZE_OUT*4;
}
GET_SHARED_GLOBAL(prefill, g_out_buffer_prefill);
/* If we have a decent number of samples, come out of underflow cond */
if (outSamps >= (OUT_BUFFER_PREFILL))
if (outSamps >= prefill)
{
outUnderflow = 0;
}
@@ -799,6 +846,8 @@ void decouple(chanend c_mix_out,
}
#endif
set_prefills(sampFreq);
while(1)
{
if (!isnull(c_clk_int))
@@ -854,13 +903,14 @@ void decouple(chanend c_mix_out,
SET_SHARED_GLOBAL(g_aud_from_host_rdptr, aud_from_host_fifo_start);
SET_SHARED_GLOBAL(g_aud_from_host_wrptr, aud_from_host_fifo_start);
SET_SHARED_GLOBAL(aud_data_remaining_to_device, 0);
/* Wait for handshake back and pass back up */
chkct(c_mix_out, XS1_CT_END);
SET_SHARED_GLOBAL(g_freqChange, 0);
asm("outct res[%0],%1"::"r"(buffer_aud_ctl_chan),"r"(XS1_CT_END));
set_prefills(sampFreq);
ENABLE_INTERRUPTS();
speedRem = 0;
@@ -883,6 +933,7 @@ void decouple(chanend c_mix_out,
SET_SHARED_GLOBAL(g_aud_to_host_buffer, g_aud_to_host_zeros);
SET_SHARED_GLOBAL(g_freqChange, 0);
set_prefills(sampFreq);
ENABLE_INTERRUPTS();
}
}
@@ -959,9 +1010,22 @@ void decouple(chanend c_mix_out,
if (space_left >= (BUFF_SIZE_OUT*4/2))
{
/* Come out of OUT overflow state */
outOverflow = 0;
DISABLE_INTERRUPTS();
outOverflow = 0;
// When we come out of overflow we clear the buffer and
// go into underflow and do a prefill again - this is to
// get a low latency and to ensure consistency between
// coming out of underflow or overflow
outUnderflow = 1;
SET_SHARED_GLOBAL(g_aud_from_host_rdptr,
aud_from_host_fifo_start);
SET_SHARED_GLOBAL(g_aud_from_host_wrptr,
aud_from_host_fifo_start);
SET_SHARED_GLOBAL(aud_data_remaining_to_device, 0);
SET_SHARED_GLOBAL(g_aud_from_host_buffer, aud_from_host_wrptr);
XUD_SetReady(aud_from_host_usb_ep, 1);
ENABLE_INTERRUPTS();
#ifdef DEBUG_LEDS
led(c_led);
#endif
@@ -988,6 +1052,7 @@ void decouple(chanend c_mix_out,
int aud_to_host_wrptr;
int aud_to_host_rdptr;
int fill_level;
unsigned prefill;
GET_SHARED_GLOBAL(aud_to_host_wrptr, g_aud_to_host_wrptr);
GET_SHARED_GLOBAL(aud_to_host_rdptr, g_aud_to_host_rdptr);
@@ -997,7 +1062,8 @@ void decouple(chanend c_mix_out,
if (fill_level < 0)
fill_level += BUFF_SIZE_IN*4;
if (fill_level >= IN_BUFFER_PREFILL)
GET_SHARED_GLOBAL(prefill, g_in_buffer_prefill);
if (fill_level >= prefill)
{
inUnderflow = 0;
SET_SHARED_GLOBAL(g_aud_to_host_buffer, aud_to_host_rdptr);