edge: Add methods for unified GPRS/EGPRS UL data block handling
The current rcv_data_block_acknowledged_gprs method is tightly
coupled to GPRS.
This commit adds variants of the involved methods that support
EGPRS and GPRS RLC encodings likewise.
Sponsored-by: On-Waves ehf
diff --git a/src/tbf_ul.cpp b/src/tbf_ul.cpp
index 4a5f21f..f2cd477 100644
--- a/src/tbf_ul.cpp
+++ b/src/tbf_ul.cpp
@@ -47,7 +47,7 @@
* Store received block data in LLC message(s) and forward to SGSN
* if complete.
*/
-int gprs_rlcmac_ul_tbf::assemble_forward_llc(const gprs_rlc_data *_data)
+int gprs_rlcmac_ul_tbf::assemble_forward_llc_gprs(const gprs_rlc_data *_data)
{
const uint8_t *data = _data->block;
uint8_t len = _data->len;
@@ -209,6 +209,50 @@
return 0;
}
+/*
+ * Store received block data in LLC message(s) and forward to SGSN
+ * if complete.
+ */
+int gprs_rlcmac_ul_tbf::assemble_forward_llc(const gprs_rlc_data *_data)
+{
+ const uint8_t *data = _data->block;
+ uint8_t len = _data->len;
+ const struct gprs_rlc_ul_data_block_info *rdbi = &_data->block_info;
+ GprsCodingScheme cs = _data->cs;
+
+ Decoding::RlcData frames[16], *frame;
+ int i, num_frames = 0;
+ uint32_t dummy_tlli;
+
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- Assembling frames: (len=%d)\n", len);
+
+ num_frames = Decoding::rlc_data_from_ul_data(
+ rdbi, cs, data, &(frames[0]), sizeof(frames),
+ &dummy_tlli);
+
+ /* create LLC frames */
+ for (i = 0; i < num_frames; i++) {
+ frame = frames + i;
+
+ LOGP(DRLCMACUL, LOGL_DEBUG, "-- Frame %d starts at offset %d, "
+ "length=%d, is_complete=%d\n",
+ i + 1, frame->offset, frame->length, frame->is_complete);
+
+ m_llc.append_frame(data + frame->offset, frame->length);
+ m_llc.consume(frame->length);
+
+ if (frame->is_complete) {
+ /* send frame to SGSN */
+ LOGP(DRLCMACUL, LOGL_INFO, "%s complete UL frame len=%d\n",
+ tbf_name(this) , m_llc.frame_length());
+ snd_ul_ud();
+ m_llc.reset();
+ }
+ }
+
+ return 0;
+}
+
struct msgb *gprs_rlcmac_ul_tbf::create_ul_ack(uint32_t fn)
{
@@ -262,6 +306,191 @@
return msg;
}
+int gprs_rlcmac_ul_tbf::rcv_data_block_acknowledged(
+ const struct gprs_rlc_ul_header_egprs *rlc,
+ uint8_t *data, uint8_t len, struct pcu_l1_meas *meas)
+{
+ int8_t rssi = meas->have_rssi ? meas->rssi : 0;
+
+ const uint16_t mod_sns = m_window.mod_sns();
+ const uint16_t ws = m_window.ws();
+
+ this->state_flags |= (1 << GPRS_RLCMAC_FLAG_UL_DATA);
+
+ LOGP(DRLCMACUL, LOGL_DEBUG, "UL DATA TFI=%d received (V(Q)=%d .. "
+ "V(R)=%d)\n", rlc->tfi, this->m_window.v_q(),
+ this->m_window.v_r());
+
+ /* process RSSI */
+ gprs_rlcmac_rssi(this, rssi);
+
+ /* store measurement values */
+ if (ms())
+ ms()->update_l1_meas(meas);
+
+ uint32_t new_tlli = 0;
+ unsigned int block_idx;
+
+ /* restart T3169 */
+ tbf_timer_start(this, 3169, bts_data()->t3169, 0);
+
+ /* Increment RX-counter */
+ this->m_rx_counter++;
+
+ /* Loop over num_blocks */
+ for (block_idx = 0; block_idx < rlc->num_data_blocks; block_idx++) {
+ int num_chunks;
+ uint8_t *rlc_data;
+ const struct gprs_rlc_ul_data_block_info *rdbi =
+ &rlc->block_info[block_idx];
+ bool need_rlc_data = false;
+ struct gprs_rlc_data *block;
+
+ LOGP(DRLCMACUL, LOGL_DEBUG,
+ "%s: Got %s RLC data block: "
+ "CV=%d, BSN=%d, SPB=%d, "
+ "PI=%d, E=%d, TI=%d, bitoffs=%d\n",
+ name(), rlc->cs.name(),
+ rdbi->cv, rdbi->bsn, rdbi->spb,
+ rdbi->pi, rdbi->e, rdbi->ti,
+ rlc->data_offs_bits[block_idx]);
+
+ /* Check whether the block needs to be decoded */
+
+ if (!m_window.is_in_window(rdbi->bsn)) {
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- BSN %d out of window "
+ "%d..%d (it's normal)\n", rdbi->bsn,
+ m_window.v_q(),
+ (m_window.v_q() + ws - 1) & mod_sns);
+ } else if (m_window.is_received(rdbi->bsn)) {
+ LOGP(DRLCMACUL, LOGL_DEBUG,
+ "- BSN %d already received\n", rdbi->bsn);
+ } else {
+ need_rlc_data = true;
+ }
+
+ if (!is_tlli_valid()) {
+ if (!rdbi->ti) {
+ LOGP(DRLCMACUL, LOGL_NOTICE,
+ "%s: Missing TLLI within UL DATA.\n",
+ name());
+ continue;
+ }
+ need_rlc_data = true;
+ }
+
+ if (!need_rlc_data)
+ continue;
+
+ /* Store block and meta info to BSN buffer */
+
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- BSN %d storing in window (%d..%d)\n",
+ rdbi->bsn, m_window.v_q(),
+ (m_window.v_q() + ws - 1) & mod_sns);
+ block = m_rlc.block(rdbi->bsn);
+ block->block_info = *rdbi;
+ block->cs = rlc->cs;
+ OSMO_ASSERT(rdbi->data_len < sizeof(block->block));
+ rlc_data = &(block->block[0]);
+ /* TODO: Handle SPB != 0 -> Set length to 2*len, add offset if
+ * 2nd part. Note that resegmentation is currently disabled
+ * within the UL assignment.
+ */
+ if (rdbi->spb) {
+ LOGP(DRLCMACUL, LOGL_NOTICE,
+ "Got SPB != 0 but resegmentation has been "
+ "disabled, skipping %s data block with BSN %d, "
+ "TFI=%d.\n", rlc->cs.name(), rdbi->bsn,
+ rlc->tfi);
+ continue;
+ }
+
+ block->len =
+ Decoding::rlc_copy_to_aligned_buffer(rlc, block_idx, data,
+ rlc_data);
+
+
+ /* TODO: Handle SPB != 0 -> set state to partly received
+ * (upper/lower) and continue with the loop, unless the other
+ * part is already present.
+ */
+
+ /* Get/Handle TLLI */
+ if (rdbi->ti) {
+ num_chunks = Decoding::rlc_data_from_ul_data(
+ rdbi, rlc->cs, rlc_data, NULL, 0, &new_tlli);
+
+ if (num_chunks < 0) {
+ bts->decode_error();
+ LOGP(DRLCMACUL, LOGL_NOTICE,
+ "Failed to decode TLLI of %s UL DATA "
+ "TFI=%d.\n", rlc->cs.name(), rlc->tfi);
+ m_window.invalidate_bsn(rdbi->bsn);
+ continue;
+ }
+ if (!this->is_tlli_valid()) {
+ if (!new_tlli) {
+ LOGP(DRLCMACUL, LOGL_NOTICE,
+ "%s: TLLI = 0 within UL DATA.\n",
+ name());
+ m_window.invalidate_bsn(rdbi->bsn);
+ continue;
+ }
+ LOGP(DRLCMACUL, LOGL_INFO,
+ "Decoded premier TLLI=0x%08x of "
+ "UL DATA TFI=%d.\n", tlli(), rlc->tfi);
+ set_tlli_from_ul(new_tlli);
+ } else if (new_tlli && new_tlli != tlli()) {
+ LOGP(DRLCMACUL, LOGL_NOTICE, "TLLI mismatch on UL "
+ "DATA TFI=%d. (Ignoring due to contention "
+ "resolution)\n", rlc->tfi);
+ m_window.invalidate_bsn(rdbi->bsn);
+ continue;
+ }
+ }
+
+ m_window.receive_bsn(rdbi->bsn);
+ }
+
+ /* Raise V(Q) if possible, and retrieve LLC frames from blocks.
+ * This is looped until there is a gap (non received block) or
+ * the window is empty.*/
+ const uint16_t v_q_beg = m_window.v_q();
+ const uint16_t count = m_window.raise_v_q();
+
+ /* Retrieve LLC frames from blocks that are ready */
+ for (uint16_t i = 0; i < count; ++i) {
+ uint16_t index = (v_q_beg + i) & mod_sns;
+ assemble_forward_llc(m_rlc.block(index));
+ }
+
+ /* Check CV of last frame in buffer */
+ if (this->state_is(GPRS_RLCMAC_FLOW) /* still in flow state */
+ && this->m_window.v_q() == this->m_window.v_r()) { /* if complete */
+ struct gprs_rlc_data *block =
+ m_rlc.block((m_window.v_r() - 1) & mod_sns);
+ const struct gprs_rlc_ul_data_block_info *rdbi =
+ &block->block_info;
+
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- No gaps in received block, "
+ "last block: BSN=%d CV=%d\n", rdbi->bsn,
+ rdbi->cv);
+ if (rdbi->cv == 0) {
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- Finished with UL "
+ "TBF\n");
+ set_state(GPRS_RLCMAC_FINISHED);
+ /* Reset N3103 counter. */
+ this->m_n3103 = 0;
+ }
+ }
+
+ /* If TLLI is included or if we received half of the window, we send
+ * an ack/nack */
+ maybe_schedule_uplink_acknack(rlc);
+
+ return 0;
+}
+
int gprs_rlcmac_ul_tbf::rcv_data_block_acknowledged_gprs(const uint8_t *data,
size_t len, struct pcu_l1_meas *meas)
{
@@ -338,7 +567,7 @@
/* Retrieve LLC frames from blocks that are ready */
for (uint16_t i = 0; i < count; ++i) {
uint16_t index = (v_q_beg + i) & mod_sns;
- assemble_forward_llc(m_rlc.block(index));
+ assemble_forward_llc_gprs(m_rlc.block(index));
}
/* Check CV of last frame in buffer */
@@ -365,6 +594,43 @@
return 0;
}
+void gprs_rlcmac_ul_tbf::maybe_schedule_uplink_acknack(
+ const gprs_rlc_ul_header_egprs *rlc)
+{
+ bool have_ti = rlc->block_info[0].ti ||
+ (rlc->num_data_blocks > 1 && rlc->block_info[1].ti);
+
+ if (rlc->si || have_ti || state_is(GPRS_RLCMAC_FINISHED) ||
+ (m_rx_counter % SEND_ACK_AFTER_FRAMES) == 0)
+ {
+ if (rlc->si) {
+ LOGP(DRLCMACUL, LOGL_NOTICE, "- Scheduling Ack/Nack, "
+ "because MS is stalled.\n");
+ }
+ if (have_ti) {
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- Scheduling Ack/Nack, "
+ "because TLLI is included.\n");
+ }
+ if (state_is(GPRS_RLCMAC_FINISHED)) {
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- Scheduling Ack/Nack, "
+ "because last block has CV==0.\n");
+ }
+ if ((m_rx_counter % SEND_ACK_AFTER_FRAMES) == 0) {
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- Scheduling Ack/Nack, "
+ "because %d frames received.\n",
+ SEND_ACK_AFTER_FRAMES);
+ }
+ if (ul_ack_state == GPRS_RLCMAC_UL_ACK_NONE) {
+ /* trigger sending at next RTS */
+ ul_ack_state = GPRS_RLCMAC_UL_ACK_SEND_ACK;
+ } else {
+ /* already triggered */
+ LOGP(DRLCMACUL, LOGL_DEBUG, "- Sending Ack/Nack is "
+ "already triggered, don't schedule!\n");
+ }
+ }
+}
+
void gprs_rlcmac_ul_tbf::maybe_schedule_uplink_acknack(const rlc_ul_header *rh)
{
if (rh->si || rh->ti || state_is(GPRS_RLCMAC_FINISHED)