diff options
Diffstat (limited to 'src/pcu_l1_if.cpp')
| -rw-r--r-- | src/pcu_l1_if.cpp | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/src/pcu_l1_if.cpp b/src/pcu_l1_if.cpp new file mode 100644 index 0000000..b95c512 --- /dev/null +++ b/src/pcu_l1_if.cpp @@ -0,0 +1,213 @@ +/* pcu_l1_if.cpp + * + * Copyright (C) 2012 Ivan Klyuchnikov + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#include <Sockets.h> +#include <gsmtap.h> +#include <gprs_rlcmac.h> +#include <pcu_l1_if.h> +#include <gprs_debug.h> + +#define MAX_UDP_LENGTH 1500 + +// TODO: We should take ports and IP from config. +UDPSocket pcu_gsmtap_socket(5077, "127.0.0.1", 4729); + +// Variable for storage current FN. +int frame_number; + +int get_current_fn() +{ + return frame_number; +} + +void set_current_fn(int fn) +{ + frame_number = fn; +} + +struct msgb *l1p_msgb_alloc(void) +{ + struct msgb *msg = msgb_alloc(sizeof(GsmL1_Prim_t), "l1_prim"); + + if (msg) + msg->l1h = msgb_put(msg, sizeof(GsmL1_Prim_t)); + + return msg; +} + +struct msgb *gen_dummy_msg(void) +{ + struct msgb *msg = l1p_msgb_alloc(); + GsmL1_Prim_t *prim = msgb_l1prim(msg); + // RLC/MAC filler with USF=1 + bitvec *filler = bitvec_alloc(23); + bitvec_unhex(filler, "41942b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + prim->id = GsmL1_PrimId_PhDataReq; + prim->u.phDataReq.sapi = GsmL1_Sapi_Pacch; + bitvec_pack(filler, prim->u.phDataReq.msgUnitParam.u8Buffer); + prim->u.phDataReq.msgUnitParam.u8Size = filler->data_len; + bitvec_free(filler); + return msg; +} + +// Send RLC/MAC block to OpenBTS. +void pcu_l1if_tx(bitvec * block, GsmL1_Sapi_t sapi, int len) +{ + struct msgb *msg = l1p_msgb_alloc(); + struct osmo_wqueue * queue; + queue = &((l1fh->fl1h)->write_q); + GsmL1_Prim_t *prim = msgb_l1prim(msg); + + prim->id = GsmL1_PrimId_PhDataReq; + prim->u.phDataReq.sapi = sapi; + bitvec_pack(block, prim->u.phDataReq.msgUnitParam.u8Buffer); + prim->u.phDataReq.msgUnitParam.u8Size = len; + osmo_wqueue_enqueue(queue, msg); +} + +int pcu_l1if_rx_pdch(GsmL1_PhDataInd_t *data_ind) +{ + bitvec *block = bitvec_alloc(data_ind->msgUnitParam.u8Size); + bitvec_unpack(block, data_ind->msgUnitParam.u8Buffer); + gprs_rlcmac_rcv_block(block); + bitvec_free(block); +} + +static int handle_ph_connect_ind(struct femtol1_hdl *fl1, GsmL1_PhConnectInd_t *connect_ind) +{ + (l1fh->fl1h)->channel_info.arfcn = connect_ind->u16Arfcn; + (l1fh->fl1h)->channel_info.tn = connect_ind->u8Tn; + (l1fh->fl1h)->channel_info.tsc = connect_ind->u8Tsc; + LOGP(DL1IF, LOGL_NOTICE, "RX: [ PCU <- BTS ] PhConnectInd: ARFCN: %u TN: %u TSC: %u \n", + connect_ind->u16Arfcn, (unsigned)connect_ind->u8Tn, (unsigned)connect_ind->u8Tsc); +} + +static int handle_ph_readytosend_ind(struct femtol1_hdl *fl1, GsmL1_PhReadyToSendInd_t *readytosend_ind) +{ + struct msgb *resp_msg; + struct osmo_wqueue * queue; + queue = &((l1fh->fl1h)->write_q); + + set_current_fn(readytosend_ind->u32Fn); + resp_msg = msgb_dequeue(&queue->msg_queue); + if (!resp_msg) { + resp_msg = gen_dummy_msg(); + if (!resp_msg) + return 0; + } + osmo_wqueue_enqueue(&l1fh->udp_wq, resp_msg); + return 1; +} + +static int handle_ph_data_ind(struct femtol1_hdl *fl1, GsmL1_PhDataInd_t *data_ind) +{ + int rc = 0; + switch (data_ind->sapi) { + case GsmL1_Sapi_Rach: + break; + case GsmL1_Sapi_Pdtch: + case GsmL1_Sapi_Pacch: + pcu_l1if_rx_pdch(data_ind); + break; + case GsmL1_Sapi_Pbcch: + case GsmL1_Sapi_Pagch: + case GsmL1_Sapi_Ppch: + case GsmL1_Sapi_Pnch: + case GsmL1_Sapi_Ptcch: + case GsmL1_Sapi_Prach: + break; + default: + LOGP(DL1IF, LOGL_NOTICE, "Rx PH-DATA.ind for unknown L1 SAPI %u \n", data_ind->sapi); + break; + } + + return rc; +} + +static int handle_ph_ra_ind(struct femtol1_hdl *fl1, GsmL1_PhRaInd_t *ra_ind) +{ + int rc = 0; + (l1fh->fl1h)->channel_info.ta = ra_ind->measParam.i16BurstTiming; + rc = gprs_rlcmac_rcv_rach(ra_ind->msgUnitParam.u8Buffer[0], ra_ind->u32Fn, ra_ind->measParam.i16BurstTiming); + return rc; +} + +/* handle any random indication from the L1 */ +int pcu_l1if_handle_l1prim(struct femtol1_hdl *fl1, struct msgb *msg) +{ + GsmL1_Prim_t *l1p = msgb_l1prim(msg); + int rc = 0; + + switch (l1p->id) { + case GsmL1_PrimId_PhConnectInd: + rc = handle_ph_connect_ind(fl1, &l1p->u.phConnectInd); + break; + case GsmL1_PrimId_PhReadyToSendInd: + rc = handle_ph_readytosend_ind(fl1, &l1p->u.phReadyToSendInd); + break; + case GsmL1_PrimId_PhDataInd: + rc = handle_ph_data_ind(fl1, &l1p->u.phDataInd); + break; + case GsmL1_PrimId_PhRaInd: + rc = handle_ph_ra_ind(fl1, &l1p->u.phRaInd); + break; + default: + break; + } + + /* Special return value '1' means: do not free */ + if (rc != 1) + msgb_free(msg); + + return rc; +} + +void gsmtap_send_llc(uint8_t * data, unsigned len) +{ + char buffer[MAX_UDP_LENGTH]; + int ofs = 0; + + // Build header + struct gsmtap_hdr *header = (struct gsmtap_hdr *)buffer; + header->version = 2; + header->hdr_len = sizeof(struct gsmtap_hdr) >> 2; + header->type = 0x08; + header->timeslot = 5; + header->arfcn = 0; + header->signal_dbm = 0; + header->snr_db = 0; + header->frame_number = 0; + header->sub_type = 0; + header->antenna_nr = 0; + header->sub_slot = 0; + header->res = 0; + + ofs += sizeof(*header); + + // Add frame data + unsigned j = 0; + for (unsigned i = ofs; i < len+ofs; i++) + { + buffer[i] = (char)data[j]; + j++; + } + ofs += len; + // Write the GSMTAP packet + pcu_gsmtap_socket.write(buffer, ofs); +} |