qi-hardware/ben-blinkenlights
1
0
Fork 0
mirror of git://projects.qi-hardware.com/ben-blinkenlights.git synced 2024-09-28 23:50:43 +03:00
Code

ubb-la/ubb-la.c: option -n N to enter experimental multi-buffer mode (WIP)

Browse Source
This commit is contained in:
Werner Almesberger 2013-01-26 23:25:17 -03:00
parent 96ae3319c5
commit 37a219b0b9
1 changed files with 104 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

107
ubb-la/ubb-la.c
View File

@ -99,6 +99,7 @@ static void dma_setup(unsigned long buf, int nibbles)
{
assert(!(nibbles & 63));
/* need to reset DSA, DTA, DTC when done. uncertain about DCS */
DCS(DMA) = DCS_NDES; /* no-descriptor transfer */
DSA(DMA) = REG_PADDR(MSC_RXFIFO); /* source */
DTA(DMA) = buf; /* destination */
@ -166,6 +167,61 @@ quit:
}
static void xfers(unsigned long *bufs, int n_bufs, int nibbles)
{
int i = 0;
dma_init();
MSC_STRPCL = MSC_STRPCRL_START_CLOCK; /* start the bus clock */
MSC_RESTO = MSC_RESTO_MASK; /* maximum response time-out */
MSC_RDTO = MSC_RDTO_MASK;
MSC_BLKLEN = nibbles >> 1;
MSC_CMDAT =
MSC_CMDAT_BUS_WIDTH_4 << MSC_CMDAT_BUS_WIDTH_SHIFT |
MSC_CMDAT_DMA_EN | /* DMA */
MSC_CMDAT_DATA_EN | /* with data transfer */
MSC_CMDAT_RESPONSE_FORMAT_NONE; /* no response required */
disable_interrupts();
OUT(UBB_CMD);
dma_setup(bufs[0], nibbles);
while (1) {
MSC_STRPCL = MSC_STRPCRL_START_OP;
while (MSC_STAT & MSC_STAT_DATA_FIFO_EMPTY);
IN(UBB_CMD);
DCS(DMA) =
DCS_NDES | /* no descriptor */
DCS_CTE; /* enable channel */
/*
* @@@ We could enable interrupts while waiting, particularly
* at low sample rates, as long as the probability of missing
* the end of the DMA transfer is acceptably low.
*/
wait_dma_done();
if (++i == n_bufs)
break;
OUT(UBB_CMD);
dma_setup(bufs[i], nibbles);
while (!(MSC_STAT & MSC_STAT_DATA_TRAN_DONE));
}
enable_interrupts();
dma_cleanup();
}
static void print_samples(FILE *file, uint8_t *buf, int skip, int nibbles)
{
uint8_t v, last = 0xff;
@ -225,6 +281,38 @@ static int do_buf(int nibbles, uint32_t trigger, uint32_t mask)
}
static void do_bufs(int n_bufs, int nibbles)
{
uint8_t *bufs[n_bufs];
struct physmem_vec vecs[n_bufs];
unsigned long addrs[n_bufs];
int i,n;
if (mlockall(MCL_CURRENT | MCL_FUTURE)) {
perror("mlockall");
exit(1);
}
for (i = 0; i != n_bufs; i++) {
bufs[i] = physmem_malloc(4096);
memset(bufs[i], 0, 4096);
physmem_flush(bufs[i], 4096);
n = physmem_xlat(bufs[i], nibbles >> 1, vecs+i, 1);
if (n != 1) {
fprintf(stderr,
"physmem_xlat_vec: expected 1, got %d\n", n);
exit(1);
}
addrs[i] = vecs[i].addr;
}
xfers(addrs, n_bufs, nibbles);
for (i = 0; i != n_bufs; i++)
print_samples(stdout, bufs[i], INITIAL_SKIP, nibbles);
}
/* ----- Command-line processing ------------------------------------------- */
@ -263,9 +351,11 @@ static unsigned long xlat_pins(unsigned long pins)
static void usage(const char *name)
{
fprintf(stderr,
"usage: %s [-C] [-t pattern/mask] [-f frequency_MHz]\n\n"
"usage: %s [-C] [-t pattern/mask] [-f frequency_MHz] [-n N]\n\n"
" -C output the MMC clock on CLK/TRIG (for debugging)\n"
" -f freq_MHz select the specified frequency (default; 1 MHz)\n"
" -n N capture N buffers worth of samples without waiting for a\n"
" trigger\n"
" -t pattern/mask start capture at the specified pattern (DAT0 = 1, etc.,\n"
" CLK = 16). Default: any change on TRIG.\n"
, name);
@ -277,12 +367,13 @@ int main(int argc, char **argv)
{
double freq_mhz = 1;
unsigned long trigger = 1, mask = 0;
unsigned long multi = 0;
int clkout = 0;
struct mmcclk clk;
char *end;
int c, res;
while ((c = getopt(argc, argv, "Cf:t:")) != EOF)
while ((c = getopt(argc, argv, "Cf:n:t:")) != EOF)
switch (c) {
case 'C':
clkout = 1;
@ -292,6 +383,11 @@ int main(int argc, char **argv)
if (*end)
usage(*argv);
break;
case 'n':
multi = strtoul(optarg, &end, 0);
if (*end)
usage(*argv);
break;
case 't':
trigger = strtoul(optarg, &end, 0);
if (*end != '/')
@ -327,7 +423,12 @@ int main(int argc, char **argv)
mask = UBB_CLK;
}
res = !do_buf(8128, trigger, mask);
if (!multi) {
res = !do_buf(8128, trigger, mask);
} else {
do_bufs(multi, 8128);
res = 0;
}
mmcclk_stop();
ubb_close(UBB_ALL);