dengweijie/lib_xua
1
0
Fork 0
forked from PAWPAW-Mirror/lib_xua
Code Pull Requests Activity

Plug in variable size queue implementation for saving buffer space in iAP.

Browse Source
This commit is contained in:
Russell
2011-12-06 17:12:44 +00:00
parent f979c80dbd
commit 1e1cb9288d
3 changed files with 49 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

47
module_usb_midi/src/queue.c
View File

@@ -1,22 +1,49 @@
#include <stdio.h>
#include "queue.h"
// Queue implementation
// Offers no protection against adding when full or dequeueing when empty.
// Uses read and write counts for pointers to distinguish full and empty cases.
// Works from c and xc
// Must allocate the memory outside of this and pass it in to init_queue so can statically allocate
// Must work for different element sizes
// This presumes that the xc compiler will not re-use the mem passed to init_queue
void init_queue(queue *q, unsigned arr[], int size) {
void init_queue(queue *q, unsigned char arr[], int size, int element_size) {
q->rdptr = 0;
q->wrptr = 0;
q->data = (uintptr_t)arr;
q->size = size; // presume that size is power of two
q->size = size; // in items, presume that size is power of two
q->element_size = element_size; // The size of each element in bytes
q->mask = size - 1;
}
extern inline void enqueue(queue *q, unsigned value) {
((unsigned *)q->data)[q->wrptr & q->mask] = value;
switch (q->element_size) {
case 4:
((unsigned *)q->data)[q->wrptr & q->mask] = value;
break;
case 1:
((unsigned char *)q->data)[q->wrptr & q->mask] = (unsigned char)value;
break;
default:
break;
}
q->wrptr++;
}
extern inline unsigned dequeue(queue *q) {
unsigned retval = ((unsigned *)q->data)[q->rdptr & q->mask];
unsigned retval;
switch (q->element_size) {
case 4:
retval = ((unsigned *)q->data)[q->rdptr & q->mask];
break;
case 1:
retval = ((unsigned char *)q->data)[q->rdptr & q->mask];
break;
default:
break;
}
q->rdptr++;
return retval;
}
@@ -41,7 +68,17 @@ extern inline int space(queue *q) {
void dump(queue *q) {
for (int i = q->rdptr; i != q->wrptr; i++) {
printf("a[%d] = %d\n", i & q->mask, ((unsigned *)q->data)[i & q->mask]);
switch (q->element_size) {
case 4:
printf("a[%d] = %d\n", i & q->mask, ((unsigned *)q->data)[i & q->mask]);
break;
case 1:
printf("a[%d] = %d\n", i & q->mask, ((unsigned char *)q->data)[i & q->mask]);
break;
default:
break;
}
}
}

3
module_usb_midi/src/queue.h
View File

@@ -9,10 +9,11 @@ typedef struct queue {
int rdptr; // Using absolute indices which count reads and writes so this needs to be considered when accessing.
int wrptr;
int size;
int element_size;
int mask;
} queue;
void init_queue(REFERENCE_PARAM(queue, q), unsigned arr[], int size);
void init_queue(REFERENCE_PARAM(queue, q), unsigned char arr[], int size, int element_size);
void enqueue(REFERENCE_PARAM(queue, q), unsigned value);
unsigned dequeue(REFERENCE_PARAM(queue, q));
int isempty(REFERENCE_PARAM(queue, q));

9
module_usb_midi/src/usb_midi.xc
View File

@@ -1,6 +1,7 @@
#include <xs1.h>
#include <xclib.h>
#include <print.h>
#include <stdint.h>
#include "usb_midi.h"
#include "midiinparse.h"
#include "midioutparse.h"
@@ -91,7 +92,7 @@ chanend c_iap, chanend ?c_i2c // iOS stuff
// One place buffer for data going out to host
queue midi_to_host_fifo;
unsigned midi_to_host_fifo_arr[1];
unsigned char midi_to_host_fifo_arr[4]; // Used for 32bit USB MIDI events
unsigned outputting_symbol, outputted_symbol;
@@ -99,14 +100,14 @@ chanend c_iap, chanend ?c_i2c // iOS stuff
// the symbol fifo (to go out of uart)
queue symbol_fifo;
unsigned symbol_fifo_arr[USB_MIDI_DEVICE_OUT_FIFO_SIZE];
unsigned char symbol_fifo_arr[USB_MIDI_DEVICE_OUT_FIFO_SIZE * 4]; // Used for 32bit USB MIDI events
unsigned rxPT, txPT;
int midi_from_host_overflow = 0;
//configure_clock_rate(clk_midi, 100, 1);
init_queue(symbol_fifo, symbol_fifo_arr, USB_MIDI_DEVICE_OUT_FIFO_SIZE);
init_queue(midi_to_host_fifo, midi_to_host_fifo_arr, 1);
init_queue(symbol_fifo, symbol_fifo_arr, USB_MIDI_DEVICE_OUT_FIFO_SIZE, 4);
init_queue(midi_to_host_fifo, midi_to_host_fifo_arr, 1, 4);
configure_out_port_no_ready(p_midi_out, clk_midi, 1);
configure_in_port(p_midi_in, clk_midi);