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Diffstat (limited to 'host/lib/transport/chdr.cpp')
| -rw-r--r-- | host/lib/transport/chdr.cpp | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/host/lib/transport/chdr.cpp b/host/lib/transport/chdr.cpp new file mode 100644 index 000000000..47ac961b9 --- /dev/null +++ b/host/lib/transport/chdr.cpp @@ -0,0 +1,182 @@ +// +// Copyright 2014 Ettus Research LLC +// +// 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 3 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, see <http://www.gnu.org/licenses/>. +// + +#include <uhd/transport/chdr.hpp> +#include <uhd/utils/byteswap.hpp> +#include <uhd/exception.hpp> + +//define the endian macros to convert integers +#ifdef BOOST_BIG_ENDIAN + #define BE_MACRO(x) (x) + #define LE_MACRO(x) uhd::byteswap(x) +#else + #define BE_MACRO(x) uhd::byteswap(x) + #define LE_MACRO(x) (x) +#endif + +using namespace uhd::transport::vrt; + +static const boost::uint32_t HDR_FLAG_TSF = (1 << 29); +static const boost::uint32_t HDR_FLAG_EOB = (1 << 28); +static const boost::uint32_t HDR_FLAG_ERROR = (1 << 28); + +/***************************************************************************/ +/* Packing */ +/***************************************************************************/ +/*! Translate the contents of \p if_packet_info into a 32-Bit word and return it. + */ +UHD_INLINE boost::uint32_t _hdr_pack_chdr( + if_packet_info_t &if_packet_info +) { + // Set fields in if_packet_info + if_packet_info.num_header_words32 = 2 + (if_packet_info.has_tsf ? 2 : 0); + if_packet_info.num_packet_words32 = + if_packet_info.num_header_words32 + + if_packet_info.num_payload_words32; + + boost::uint16_t pkt_length = + if_packet_info.num_payload_bytes + (4 * if_packet_info.num_header_words32); + boost::uint32_t chdr = 0 + // 2 Bits: Packet type + | (if_packet_info.packet_type << 30) + // 1 Bit: Has time + | (if_packet_info.has_tsf ? HDR_FLAG_TSF : 0) + // 1 Bit: EOB or Error + | ((if_packet_info.eob or if_packet_info.error) ? HDR_FLAG_EOB : 0) + // 12 Bits: Sequence number + | ((if_packet_info.packet_count & 0xFFF) << 16) + // 16 Bits: Total packet length + | pkt_length; + return chdr; +} + +void chdr::if_hdr_pack_be( + boost::uint32_t *packet_buff, + if_packet_info_t &if_packet_info +) { + // Write header and update if_packet_info + packet_buff[0] = BE_MACRO(_hdr_pack_chdr(if_packet_info)); + + // Write SID + packet_buff[1] = BE_MACRO(if_packet_info.sid); + + // Write time + if (if_packet_info.has_tsf) { + packet_buff[2] = BE_MACRO(boost::uint32_t(if_packet_info.tsf >> 32)); + packet_buff[3] = BE_MACRO(boost::uint32_t(if_packet_info.tsf >> 0)); + } +} + +void chdr::if_hdr_pack_le( + boost::uint32_t *packet_buff, + if_packet_info_t &if_packet_info +) { + // Write header and update if_packet_info + packet_buff[0] = LE_MACRO(_hdr_pack_chdr(if_packet_info)); + + // Write SID + packet_buff[1] = LE_MACRO(if_packet_info.sid); + + // Write time + if (if_packet_info.has_tsf) { + packet_buff[2] = LE_MACRO(boost::uint32_t(if_packet_info.tsf >> 32)); + packet_buff[3] = LE_MACRO(boost::uint32_t(if_packet_info.tsf >> 0)); + } +} + + +/***************************************************************************/ +/* Unpacking */ +/***************************************************************************/ +UHD_INLINE void _hdr_unpack_chdr( + const boost::uint32_t chdr, + if_packet_info_t &if_packet_info +) { + // Set constant members + if_packet_info.link_type = if_packet_info_t::LINK_TYPE_CHDR; + if_packet_info.has_cid = false; + if_packet_info.has_sid = true; + if_packet_info.has_tsi = false; + if_packet_info.has_tlr = false; + if_packet_info.sob = false; + + // Set configurable members + if_packet_info.has_tsf = bool(chdr & HDR_FLAG_TSF); + if_packet_info.packet_type = if_packet_info_t::packet_type_t((chdr >> 30) & 0x3); + if_packet_info.eob = (if_packet_info.packet_type == if_packet_info_t::PACKET_TYPE_DATA) + && bool(chdr & HDR_FLAG_EOB); + if_packet_info.error = (if_packet_info.packet_type == if_packet_info_t::PACKET_TYPE_RESP) + && bool(chdr & HDR_FLAG_ERROR); + if_packet_info.packet_count = (chdr >> 16) & 0xFFF; + + // Set packet length variables + if (if_packet_info.has_tsf) { + if_packet_info.num_header_words32 = 4; + } else { + if_packet_info.num_header_words32 = 2; + } + size_t pkt_size_bytes = (chdr & 0xFFFF); + size_t pkt_size_word32 = (pkt_size_bytes / 4) + ((pkt_size_bytes % 4) ? 1 : 0); + // Check lengths match: + if (pkt_size_word32 < if_packet_info.num_header_words32) { + throw uhd::value_error("Bad CHDR or invalid packet length"); + } + if (if_packet_info.num_packet_words32 < pkt_size_word32) { + throw uhd::value_error("Bad CHDR or packet fragment"); + } + if_packet_info.num_payload_bytes = pkt_size_bytes - (4 * if_packet_info.num_header_words32); + if_packet_info.num_payload_words32 = pkt_size_word32 - if_packet_info.num_header_words32; +} + +void chdr::if_hdr_unpack_be( + const boost::uint32_t *packet_buff, + if_packet_info_t &if_packet_info +) { + // Read header and update if_packet_info + boost::uint32_t chdr = BE_MACRO(packet_buff[0]); + _hdr_unpack_chdr(chdr, if_packet_info); + + // Read SID + if_packet_info.sid = BE_MACRO(packet_buff[1]); + + // Read time (has_tsf was updated earlier) + if (if_packet_info.has_tsf) { + if_packet_info.tsf = 0 + | boost::uint64_t(BE_MACRO(packet_buff[2])) << 32 + | BE_MACRO(packet_buff[3]); + } +} + +void chdr::if_hdr_unpack_le( + const boost::uint32_t *packet_buff, + if_packet_info_t &if_packet_info +) { + // Read header and update if_packet_info + boost::uint32_t chdr = LE_MACRO(packet_buff[0]); + _hdr_unpack_chdr(chdr, if_packet_info); + + // Read SID + if_packet_info.sid = LE_MACRO(packet_buff[1]); + + // Read time (has_tsf was updated earlier) + if (if_packet_info.has_tsf) { + if_packet_info.tsf = 0 + | boost::uint64_t(LE_MACRO(packet_buff[2])) << 32 + | LE_MACRO(packet_buff[3]); + } +} + |