From 4f677e6ba8434dab376495cd996d140548fa6e93 Mon Sep 17 00:00:00 2001 From: Vadim Yanitskiy Date: Fri, 15 May 2020 19:18:21 +0700 Subject: trxcon: refactor trx_if_cmd_setfh(): send Rx/Tx frequencies It would make sense to send the ARFCN list in parameters of SETFH command, if there was a clear distinction between transceivers in fake_trx.py, i.e. which one is an MS and which is a BTS. Right now, every Transceiver is an abstract entity that emits and receives bursts. So when you convert an ARFCN to a pair of Downlink/Uplink frequencies, you don't know whether it maps as Rx/Tx or as Tx/Rx for a given Transceiver. Of course, we could assume that this is an MS specific feature, and a pair of Downlink/Uplink frequencies always corresponds to Rx/Tx, but what if some day we would need to implement and test a similar approach for the BTS side? Also, by sending frequency values in kHz (rather than ARFCNs) we can avoid inconsistency with the existing RXTUNE / TXTUNE commands. Change-Id: Ia2bf08797f1a37b56cf47945694b901f92765b58 Related: I587e4f5da67c7b7f28e010ed46b24622c31a3fdd Related: OS#4546 --- src/host/trxcon/trx_if.c | 56 +++++++++++++++++++++++++++++++----------------- 1 file changed, 36 insertions(+), 20 deletions(-) diff --git a/src/host/trxcon/trx_if.c b/src/host/trxcon/trx_if.c index cb54c9ed..91f84ec4 100644 --- a/src/host/trxcon/trx_if.c +++ b/src/host/trxcon/trx_if.c @@ -397,41 +397,57 @@ int trx_if_cmd_setta(struct trx_instance *trx, int8_t ta) } /* - * Frequency Hopping parameters indication + * Frequency Hopping parameters indication. * - * SETFH instructs transceiver to enable frequency - * hopping mode using the given parameters. - * CMD SETFH [... ] + * SETFH instructs transceiver to enable frequency hopping mode + * using the given HSN, MAIO, and Mobile Allocation parameters. + * + * CMD SETFH [... ] + * + * where and is a pair of Rx/Tx frequencies (in kHz) + * corresponding to one ARFCN the Mobile Allocation. Note that the + * channel list is expected to be sorted in ascending order. */ int trx_if_cmd_setfh(struct trx_instance *trx, uint8_t hsn, uint8_t maio, uint16_t *ma, size_t ma_len) { - char ma_buf[100]; + /* Reserve some room for CMD SETFH */ + char ma_buf[TRXC_BUF_SIZE - 24]; + size_t ma_buf_len = sizeof(ma_buf) - 1; + uint16_t rx_freq, tx_freq; char *ptr; int i, rc; - /* No channels, WTF?!? */ - if (!ma_len) + /* Make sure that Mobile Allocation has at least one ARFCN */ + if (!ma_len || ma == NULL) { + LOGP(DTRX, LOGL_ERROR, "Mobile Allocation is empty?!?\n"); return -EINVAL; + } - /** - * Compose a sequence of channels (mobile allocation) - * FIXME: the length of a CTRL command is limited to 128 symbols, - * so we may have some problems if there are many channels... - */ + /* Compose a sequence of Rx/Tx frequencies (mobile allocation) */ for (i = 0, ptr = ma_buf; i < ma_len; i++) { - /* Append a channel */ - rc = snprintf(ptr, ma_buf + sizeof(ma_buf) - ptr, "%u ", ma[i]); - if (rc < 0) - return rc; + /* Convert ARFCN to a pair of Rx/Tx frequencies (Hz * 10) */ + rx_freq = gsm_arfcn2freq10(ma[i], 0); /* Rx: Downlink */ + tx_freq = gsm_arfcn2freq10(ma[i], 1); /* Tx: Uplink */ + if (rx_freq == 0xffff || tx_freq == 0xffff) { + LOGP(DTRX, LOGL_ERROR, "Failed to convert ARFCN %u " + "to a pair of Rx/Tx frequencies\n", + ma[i] & ~ARFCN_FLAG_MASK); + return -EINVAL; + } + + /* Append a pair of Rx/Tx frequencies (in kHz) to the buffer */ + rc = snprintf(ptr, ma_buf_len, "%u %u ", rx_freq * 100, tx_freq * 100); + if (rc < 0 || rc > ma_buf_len) { /* Prevent buffer overflow */ + LOGP(DTRX, LOGL_ERROR, "Not enough room to encode " + "Mobile Allocation (N=%zu)\n", ma_len); + return -ENOSPC; + } /* Move pointer */ + ma_buf_len -= rc; ptr += rc; - - /* Prevent buffer overflow */ - if (ptr >= (ma_buf + 100)) - return -EIO; } /* Overwrite the last space */ -- cgit v1.2.3