return SR_OK;
}
-static uint32_t get_channels_mask(const struct sr_dev_inst *sdi)
+/*
+ * Determine the number of enabled channels as well as their bitmask
+ * representation. Derive data here which later simplifies processing
+ * of raw capture data memory content in streaming mode.
+ */
+static void la2016_prepare_stream(const struct sr_dev_inst *sdi)
{
- uint32_t channels;
+ struct dev_context *devc;
+ struct stream_state_t *stream;
+ size_t channel_mask;
GSList *l;
struct sr_channel *ch;
- channels = 0;
+ devc = sdi->priv;
+ stream = &devc->stream;
+ memset(stream, 0, sizeof(*stream));
+
+ stream->enabled_count = 0;
for (l = sdi->channels; l; l = l->next) {
ch = l->data;
if (ch->type != SR_CHANNEL_LOGIC)
continue;
if (!ch->enabled)
continue;
- channels |= 1UL << ch->index;
+ channel_mask = 1UL << ch->index;
+ stream->enabled_mask |= channel_mask;
+ stream->channel_masks[stream->enabled_count++] = channel_mask;
}
-
- return channels;
+ stream->channel_index = 0;
}
+/*
+ * This routine configures the set of enabled channels, as well as the
+ * trigger condition (if one was specified). Also prepares the capture
+ * data processing in stream mode, where the memory layout dramatically
+ * differs from normal mode.
+ */
static int set_trigger_config(const struct sr_dev_inst *sdi)
{
struct dev_context *devc;
uint8_t *wrptr;
devc = sdi->priv;
- trigger = sr_session_trigger_get(sdi->session);
-
- memset(&cfg, 0, sizeof(cfg));
- cfg.channels = get_channels_mask(sdi);
+ la2016_prepare_stream(sdi);
+ memset(&cfg, 0, sizeof(cfg));
+ cfg.channels = devc->stream.enabled_mask;
+ if (!cfg.channels) {
+ sr_err("Need at least one enabled logic channel.");
+ return SR_ERR_ARG;
+ }
+ trigger = sr_session_trigger_get(sdi->session);
if (trigger && trigger->stages) {
stages = trigger->stages;
stage1 = stages->data;
"level-triggered 0x%04x, high/falling 0x%04x.",
cfg.channels, cfg.enabled, cfg.level, cfg.high_or_falling);
+ /*
+ * Don't configure hardware trigger parameters in streaming mode
+ * or when the device lacks local memory. Yet the above dump of
+ * derived parameters from user specs is considered valueable.
+ *
+ * TODO Add support for soft triggers when hardware triggers in
+ * the device are not used or are not available at all.
+ */
+ if (!devc->model->memory_bits || devc->continuous) {
+ if (!devc->model->memory_bits)
+ sr_dbg("Device without memory. No hardware triggers.");
+ else if (devc->continuous)
+ sr_dbg("Streaming mode. No hardware triggers.");
+ cfg.enabled = 0;
+ cfg.level = 0;
+ cfg.high_or_falling = 0;
+ }
+
devc->trigger_involved = cfg.enabled != 0;
wrptr = buf;
return SR_OK;
}
+/*
+ * This routine communicates the sample configuration to the device:
+ * Total samples count and samplerate, pre-trigger configuration.
+ */
static int set_sample_config(const struct sr_dev_inst *sdi)
{
struct dev_context *devc;
uint64_t min_samplerate, eff_samplerate;
+ uint64_t stream_bandwidth;
uint16_t divider_u16;
uint64_t limit_samples;
uint64_t pre_trigger_samples;
* limit the amount of sample memory to use for pre-trigger
* data. Only the upper 24 bits of that memory size spec get
* communicated to the device (written to its FPGA register).
- *
- * TODO Determine whether the pre-trigger memory size gets
- * specified in samples or in bytes. A previous implementation
- * suggests bytes but this is suspicious when every other spec
- * is in terms of samples.
*/
- if (devc->trigger_involved) {
+ if (!devc->model->memory_bits) {
+ sr_dbg("Memory-less device, skipping pre-trigger config.");
+ pre_trigger_samples = 0;
+ pre_trigger_memory = 0;
+ } else if (devc->trigger_involved) {
pre_trigger_samples = limit_samples;
pre_trigger_samples *= devc->capture_ratio;
pre_trigger_samples /= 100;
pre_trigger_memory /= 100;
} else {
sr_dbg("No trigger setup, skipping pre-trigger config.");
- pre_trigger_samples = 1;
+ pre_trigger_samples = 0;
pre_trigger_memory = 0;
}
/* Ensure non-zero value after LSB shift out in HW reg. */
- if (pre_trigger_memory < 0x100) {
+ if (pre_trigger_memory < 0x100)
pre_trigger_memory = 0x100;
- }
- sr_dbg("Set sample config: %" PRIu64 "kHz, %" PRIu64 " samples.",
- eff_samplerate / SR_KHZ(1), limit_samples);
+ sr_dbg("Set sample config: %" PRIu64 "kHz (div %" PRIu16 "), %" PRIu64 " samples.",
+ eff_samplerate / SR_KHZ(1), divider_u16, limit_samples);
sr_dbg("Capture ratio %" PRIu64 "%%, count %" PRIu64 ", mem %" PRIu64 ".",
devc->capture_ratio, pre_trigger_samples, pre_trigger_memory);
+ if (devc->continuous) {
+ stream_bandwidth = eff_samplerate;
+ stream_bandwidth *= devc->stream.enabled_count;
+ sr_dbg("Streaming: channel count %zu, product %" PRIu64 ".",
+ devc->stream.enabled_count, stream_bandwidth);
+ stream_bandwidth /= 1000 * 1000;
+ if (stream_bandwidth >= LA2016_STREAM_MBPS_MAX) {
+ sr_warn("High USB stream bandwidth: %" PRIu64 "Mbps.",
+ stream_bandwidth);
+ }
+ if (stream_bandwidth < LA2016_STREAM_PUSH_THR) {
+ sr_dbg("Streaming: low Mbps, suggest periodic flush.");
+ devc->stream.flush_period_ms = LA2016_STREAM_PUSH_IVAL;
+ }
+ }
+
/*
* The acquisition configuration occupies a total of 16 bytes:
* - A 34bit total samples count limit (up to 10 billions) that
SR_PRIV int la2016_setup_acquisition(const struct sr_dev_inst *sdi,
double voltage)
{
+ struct dev_context *devc;
int ret;
uint8_t cmd;
+ devc = sdi->priv;
+
ret = set_threshold_voltage(sdi, voltage);
if (ret != SR_OK)
return ret;
- cmd = CAPTMODE_TO_RAM;
+ cmd = devc->continuous ? CAPTMODE_STREAM : CAPTMODE_TO_RAM;
ret = ctrl_out(sdi, CMD_FPGA_SPI, REG_CAPT_MODE, 0, &cmd, sizeof(cmd));
if (ret != SR_OK) {
sr_err("Cannot send command to stop sampling.");
SR_PRIV int la2016_start_acquisition(const struct sr_dev_inst *sdi)
{
+ struct dev_context *devc;
int ret;
+ devc = sdi->priv;
+
ret = la2016_usbxfer_allocate(sdi);
if (ret != SR_OK)
return ret;
- ret = set_run_mode(sdi, RUNMODE_RUN);
- if (ret != SR_OK)
- return ret;
+ if (devc->continuous) {
+ ret = ctrl_out(sdi, CMD_BULK_RESET, 0x00, 0, NULL, 0);
+ if (ret != SR_OK)
+ return ret;
+
+ ret = la2016_usbxfer_submit_all(sdi);
+ if (ret != SR_OK)
+ return ret;
+
+ /*
+ * Periodic receive callback will set runmode. This
+ * activity MUST be close to data reception, a pause
+ * between these steps breaks the stream's operation.
+ */
+ } else {
+ ret = set_run_mode(sdi, RUNMODE_RUN);
+ if (ret != SR_OK)
+ return ret;
+ }
return SR_OK;
}
static int la2016_stop_acquisition(const struct sr_dev_inst *sdi)
{
+ struct dev_context *devc;
int ret;
ret = set_run_mode(sdi, RUNMODE_HALT);
if (ret != SR_OK)
return ret;
+ devc = sdi->priv;
+ if (devc->continuous)
+ devc->download_finished = TRUE;
+
return SR_OK;
}
sr_dbg("Total samples after chunk: %" PRIu64 ".", devc->total_samples);
}
+/*
+ * Process a chunk of capture data in streaming mode. The memory layout
+ * is rather different from "normal mode" (see the send_chunk() routine
+ * above). In streaming mode data is not compressed, and memory cells
+ * neither contain raw sampled pin values at a given point in time. The
+ * memory content needs transformation.
+ * - The memory content can be seen as a sequence of memory cells.
+ * - Each cell contains samples that correspond to the same channel.
+ * The next cell contains samples for the next channel, etc.
+ * - Only enabled channels occupy memory cells. Disabled channels are
+ * not part of the capture data memory layout.
+ * - The LSB bit position in a cell is the sample which was taken first
+ * for this channel. Upper bit positions were taken later.
+ *
+ * Implementor's note: This routine is inspired by convert_sample_data()
+ * in the https://github.com/AlexUg/sigrok implementation. Which in turn
+ * appears to have been derived from the saleae-logic16 sigrok driver.
+ * The code is phrased conservatively to verify the layout as discussed
+ * above, performance was not a priority. Operation was verified with an
+ * LA2016 device. The memory layout of 32 channel models is yet to get
+ * determined.
+ */
+static void stream_data(struct sr_dev_inst *sdi,
+ const uint8_t *data_buffer, size_t data_length)
+{
+ struct dev_context *devc;
+ struct stream_state_t *stream;
+ size_t bit_count;
+ const uint8_t *rp;
+ uint32_t sample_value;
+ uint8_t sample_buff[sizeof(sample_value)];
+ size_t bit_idx;
+ uint32_t ch_mask;
+
+ devc = sdi->priv;
+ stream = &devc->stream;
+
+ /* Ignore incoming USB data after complete sample data download. */
+ if (devc->download_finished)
+ return;
+ sr_dbg("Stream mode, got another chunk: %p, length %zu.",
+ data_buffer, data_length);
+
+ /* TODO Add soft trigger support when in stream mode? */
+
+ /*
+ * TODO Are memory cells always as wide as the channel count?
+ * Are they always 16bits wide? Verify for 32 channel devices.
+ */
+ bit_count = devc->model->channel_count;
+ if (bit_count == 32) {
+ data_length /= sizeof(uint32_t);
+ } else if (bit_count == 16) {
+ data_length /= sizeof(uint16_t);
+ } else {
+ /*
+ * Unhandled case. Acquisition should not start.
+ * The statement silences the compiler.
+ */
+ return;
+ }
+ rp = data_buffer;
+ sample_value = 0;
+ while (data_length--) {
+ /* Get another entity. */
+ if (bit_count == 32)
+ sample_value = read_u32le_inc(&rp);
+ else if (bit_count == 16)
+ sample_value = read_u16le_inc(&rp);
+
+ /* Map the entity's bits to a channel's samples. */
+ ch_mask = stream->channel_masks[stream->channel_index];
+ for (bit_idx = 0; bit_idx < bit_count; bit_idx++) {
+ if (sample_value & (1UL << bit_idx))
+ stream->sample_data[bit_idx] |= ch_mask;
+ }
+
+ /*
+ * Advance to the next channel. Submit a block of
+ * samples when all channels' data was seen.
+ */
+ stream->channel_index++;
+ if (stream->channel_index != stream->enabled_count)
+ continue;
+ for (bit_idx = 0; bit_idx < bit_count; bit_idx++) {
+ sample_value = stream->sample_data[bit_idx];
+ write_u32le(sample_buff, sample_value);
+ feed_queue_logic_submit(devc->feed_queue, sample_buff, 1);
+ }
+ sr_sw_limits_update_samples_read(&devc->sw_limits, bit_count);
+ devc->total_samples += bit_count;
+ memset(stream->sample_data, 0, sizeof(stream->sample_data));
+ stream->channel_index = 0;
+ }
+
+ /*
+ * Need we count empty or failed USB transfers? This version
+ * doesn't, assumes that timeouts are perfectly legal because
+ * transfers are started early, and slow samplerates or trigger
+ * support in hardware are plausible causes for empty transfers.
+ *
+ * TODO Maybe a good condition would be (rather large) a timeout
+ * after a previous capture data chunk was seen? So that stalled
+ * streaming gets detected which _is_ an exceptional condition.
+ * We have observed these when "runmode" is set early but bulk
+ * transfers start late with a pause after setting the runmode.
+ */
+ if (sr_sw_limits_check(&devc->sw_limits)) {
+ sr_dbg("Acquisition end reached (sw limits).");
+ devc->download_finished = TRUE;
+ }
+ if (devc->download_finished) {
+ sr_dbg("Stream receive done, flushing session feed queue.");
+ feed_queue_logic_flush(devc->feed_queue);
+ }
+ sr_dbg("Total samples after chunk: %" PRIu64 ".", devc->total_samples);
+}
+
static void LIBUSB_CALL receive_transfer(struct libusb_transfer *transfer)
{
struct sr_dev_inst *sdi;
* or exhausting the device's captured data will complete the
* sample data download.
*/
- send_chunk(sdi, transfer->buffer, transfer->actual_length);
+ if (devc->continuous)
+ stream_data(sdi, transfer->buffer, transfer->actual_length);
+ else
+ send_chunk(sdi, transfer->buffer, transfer->actual_length);
/*
* Re-submit completed transfers (regardless of timeout or
devc = sdi->priv;
drvc = sdi->driver->context;
+ /* Arrange for the start of stream mode when requested. */
+ if (devc->continuous && !devc->frame_begin_sent) {
+ sr_dbg("First receive callback in stream mode.");
+ devc->download_finished = FALSE;
+ devc->trigger_marked = FALSE;
+ devc->total_samples = 0;
+
+ std_session_send_df_frame_begin(sdi);
+ devc->frame_begin_sent = TRUE;
+
+ ret = set_run_mode(sdi, RUNMODE_RUN);
+ if (ret != SR_OK) {
+ sr_err("Cannot set 'runmode' to 'run'.");
+ return FALSE;
+ }
+
+ ret = ctrl_out(sdi, CMD_BULK_START, 0x00, 0, NULL, 0);
+ if (ret != SR_OK) {
+ sr_err("Cannot start USB bulk transfers.");
+ return FALSE;
+ }
+ sr_dbg("Stream data reception initiated.");
+ }
+
/*
* Wait for the acquisition to complete in hardware.
* Periodically check a potentially configured msecs timeout.
*/
- if (!devc->completion_seen) {
+ if (!devc->continuous && !devc->completion_seen) {
if (!la2016_is_idle(sdi)) {
if (sr_sw_limits_check(&devc->sw_limits)) {
devc->sw_limits.limit_msec = 0;
memset(&tv, 0, sizeof(tv));
libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
+ /*
+ * Periodically flush acquisition data in streaming mode.
+ * Without this nudge, previously received and accumulated data
+ * keeps sitting in queues and is not seen by applications.
+ */
+ if (devc->continuous && devc->stream.flush_period_ms) {
+ uint64_t now, elapsed;
+ now = g_get_monotonic_time();
+ if (!devc->stream.last_flushed)
+ devc->stream.last_flushed = now;
+ elapsed = now - devc->stream.last_flushed;
+ elapsed /= 1000;
+ if (elapsed >= devc->stream.flush_period_ms) {
+ sr_dbg("Stream mode, flushing.");
+ feed_queue_logic_flush(devc->feed_queue);
+ devc->stream.last_flushed = now;
+ }
+ }
+
/* Postprocess completion of sample data download. */
if (devc->download_finished) {
sr_dbg("Download finished, post processing.");
projects / libsigrok.git / commitdiff