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/* |
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* Copyright (C) 2005-2009 by Jonathan Woithe |
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* Copyright (C) 2005-2008 by Pieter Palmers |
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* |
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* This file is part of FFADO |
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* FFADO = Free Firewire (pro-)audio drivers for linux |
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* |
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* FFADO is based upon FreeBoB. |
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* |
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* This program is free software: you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation, either version 2 of the License, or |
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* (at your option) version 3 of the License. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program. If not, see <http://www.gnu.org/licenses/>. |
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* |
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*/ |
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|
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/* CAUTION: this module is under active development. It has been templated |
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* from the MOTU driver and many MOTU-specific details remain. Do not use |
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* this file as a reference for RME devices until initial development has |
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* been completed. |
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*/ |
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#include "libutil/float_cast.h" |
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#include "RmeReceiveStreamProcessor.h" |
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#include "RmePort.h" |
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#include "../StreamProcessorManager.h" |
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#include "devicemanager.h" |
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#include "libieee1394/ieee1394service.h" |
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#include "libieee1394/IsoHandlerManager.h" |
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#include "libieee1394/cycletimer.h" |
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#include "libutil/ByteSwap.h" |
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// This is to pick up the RME_MODEL_* constants. There's probably a better |
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// way ... |
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#include "../../rme/rme_avdevice.h" |
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#include <cstring> |
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#include <math.h> |
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#include <assert.h> |
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/* Provide more intuitive access to GCC's branch predition built-ins */ |
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#define likely(x) __builtin_expect((x),1) |
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#define unlikely(x) __builtin_expect((x),0) |
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namespace Streaming { |
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// A macro to extract specific bits from a native endian quadlet |
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#define get_bits(_d,_start,_len) (((_d)>>((_start)-(_len)+1)) & ((1<<(_len))-1)) |
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|
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RmeReceiveStreamProcessor::RmeReceiveStreamProcessor(FFADODevice &parent, |
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unsigned int model, unsigned int event_size) |
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: StreamProcessor(parent, ePT_Receive) |
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, n_hw_tx_buffer_samples ( -1 ) |
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, m_rme_model( model ) |
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, m_event_size( event_size ) |
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, rxdll_t1( 0 ) |
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, rxdll_e2( 0 ) |
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, mb_head ( 0 ) |
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, mb_tail ( 0 ) |
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{ |
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} |
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unsigned int |
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RmeReceiveStreamProcessor::getMaxPacketSize() { |
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int framerate = m_Parent.getDeviceManager().getStreamProcessorManager().getNominalRate(); |
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// FIXME: the additional 8 bytes is not needed. |
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// FIXME: the upper bounds of the 1x and 2x rates need to account for the |
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// DDS capability to run fast by 4%. |
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if (m_rme_model == Rme::RME_MODEL_FIREFACE800) |
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return 8 + (framerate<=48000?784:(framerate<=96000?1200:1200)); |
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else |
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return 8 + (framerate<=48000?504:(framerate<=96000?840:1000)); |
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} |
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unsigned int |
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RmeReceiveStreamProcessor::getNominalFramesPerPacket() { |
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int framerate = m_Parent.getDeviceManager().getStreamProcessorManager().getNominalRate(); |
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return framerate<=48000?7:(framerate<=96000?15:25); |
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} |
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#define RXDLL_BANDWIDTH (0.003) |
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bool |
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RmeReceiveStreamProcessor::prepareChild() { |
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double w; |
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debugOutput( DEBUG_LEVEL_VERBOSE, "Preparing (%p)...\n", this); |
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// prepare the framerate estimate |
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// FIXME: not needed anymore? |
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//m_ticks_per_frame = (TICKS_PER_SECOND*1.0) / ((float)m_Parent.getDeviceManager().getStreamProcessorManager().getNominalRate()); |
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// Initialise the "smoothing" DLL. rxdll_e2 is set to the expected |
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// period (in ticks) which is then used to set suitable coefficients |
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// based on a normalised bandwidth. |
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rxdll_t1 = -1.0; |
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rxdll_e2 = (TICKS_PER_SECOND*1.0) / ((float)m_Parent.getDeviceManager().getStreamProcessorManager().getNominalRate()); |
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// w = (2*M_PI*RXDLL_BANDWIDTH*rxdll_e2); |
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//w = (2*M_PI*0.004); |
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//w = (2*M_PI*0.00225); |
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w = (2*M_PI*0.001); |
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rxdll_B = (sqrt(2.0)*w); |
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rxdll_C = (w*w); |
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debugOutput( DEBUG_LEVEL_VERBOSE, "init: e2=%g, w=%g, B=%g, C=%g\n", |
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rxdll_e2, w, rxdll_B, rxdll_C); |
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// Request that the iso streaming be started as soon as possible by the |
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// kernel. |
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m_IsoHandlerManager.setIsoStartCycleForStream(this, -1); |
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return true; |
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} |
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/* |
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* Processes packet header to extract timestamps and check if the packet is |
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* valid. |
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*/ |
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enum StreamProcessor::eChildReturnValue |
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RmeReceiveStreamProcessor::processPacketHeader(unsigned char *data, unsigned int length, |
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unsigned char tag, unsigned char sy, |
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uint32_t pkt_ctr) |
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{ |
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// For testing |
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static signed int rep = 0; |
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static unsigned long long int prevts = 0; |
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quadlet_t *adata = (quadlet_t *)data; |
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if (rep == 0) { |
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// debugOutput(DEBUG_LEVEL_VERBOSE, "data packet header, len=%d\n", length); |
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fprintf(stderr, "first data packet header, len=%d\n", length); |
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} |
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//fprintf(stderr, "recv len=%d\n", length); |
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if (length > 0) { |
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// The iso data blocks from the RMEs comprise 24-bit audio |
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// data encoded in 32-bit integers. The LSB of the 32-bit integers |
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// of certain channels are used for house-keeping information. |
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// The number of samples for each channel present in a packet |
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// varies: 7 for 1x rates, 15 for 2x rates and 25 for 4x rates. |
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// quadlet_t *quadlet = (quadlet_t *)data; |
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// Don't even attempt to process a packet if it isn't what we expect |
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// from an RME. For now the only condition seems to be a tag of 0. |
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// This will be fleshed out in due course. |
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// if (tag!=1) { |
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// return eCRV_Invalid; |
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// } |
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// Timestamps are not transmitted explicitly by the RME interfaces |
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// so we'll have to fake it somehow in order to fit in with the rest |
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// of the FFADO infrastructure. For now just take the packet |
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// arrival time as the "last timestamp" and feed it into a local |
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// DLL to "smooth over" the abrupt jumps which would otherwise be |
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// associated with a skipped iso cycle. In practice there is a |
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// fixed offset that we'll have to include eventually. |
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uint64_t pkt_ctr_ticks = CYCLE_TIMER_TO_TICKS(pkt_ctr); |
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double e = pkt_ctr_ticks - rxdll_t1; |
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if (e < -64LL*TICKS_PER_SECOND) |
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e += 128LL*TICKS_PER_SECOND; |
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// if (e < 0) |
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// e += 128LL*TICKS_PER_SECOND; |
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// Very large e values indicate a discontinuity in processing, possibly due |
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// to an xrun. In this case, reset the DLL to avoid long delays as it |
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// resynchronises. |
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if (e > 10000) { |
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rxdll_t1 = -1.0; |
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rxdll_e2 = (TICKS_PER_SECOND*1.0) / ((float)m_Parent.getDeviceManager().getStreamProcessorManager().getNominalRate()); |
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} |
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int64_t newts=0; |
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#if 0 |
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double p = m_last_timestamp; |
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debugOutput(DEBUG_LEVEL_VERBOSE, "ts read: %lld, prev=%lld, diff=%lld\n", |
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pkt_ctr_ticks, prevts, pkt_ctr_ticks-prevts); |
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debugOutput(DEBUG_LEVEL_VERBOSE, " rxdll_t1=%g\n", rxdll_t1); |
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#endif |
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if (rxdll_t1 < 0.0) { |
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signed int n_frames = length / m_event_size; |
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rxdll_e2 *= n_frames; |
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rxdll_t1 = pkt_ctr_ticks + rxdll_e2; |
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newts = pkt_ctr_ticks - rxdll_e2 - (0*3072); |
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if (newts < 0) |
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newts += 128LL*TICKS_PER_SECOND; |
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m_data_buffer->setBufferTailTimestamp(newts); |
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newts = pkt_ctr_ticks; |
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//debugOutput(DEBUG_LEVEL_VERBOSE, " INIT\n"); |
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} else { |
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newts = rxdll_t1; |
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rxdll_t1 += rxdll_B*e + rxdll_e2; |
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rxdll_e2 += rxdll_C*e; |
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} |
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if (rxdll_t1 >= 128LL*TICKS_PER_SECOND) |
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rxdll_t1 -= 128LL*TICKS_PER_SECOND; |
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//newts += (6.0/7.00)*rxdll_e2; |
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newts -= (0*3072); // Make there be some sort of latency |
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if (newts < 0) |
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newts += 128LL*TICKS_PER_SECOND; |
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else |
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if (newts >= 128LL*TICKS_PER_SECOND) |
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newts -= 128LL*TICKS_PER_SECOND; |
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#if 1 |
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// 3584 |
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if (newts-m_last_timestamp > 4000) { |
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debugOutput(DEBUG_LEVEL_VERBOSE, " **** \n"); |
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} |
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debugOutput(DEBUG_LEVEL_VERBOSE, " returned: %lld (e=%g) T=%g, f=%g\n", |
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newts, e, rxdll_e2, 7.0/rxdll_e2*24576000); |
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debugOutput(DEBUG_LEVEL_VERBOSE, " diff=%lld, f=%g\n", |
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newts-m_last_timestamp, 24576000/((newts-m_last_timestamp)/7.0)); |
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debugOutput(DEBUG_LEVEL_VERBOSE, " ts read: %lld, prev=%lld, diff=%lld\n", |
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pkt_ctr_ticks, prevts, pkt_ctr_ticks-prevts); |
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#endif |
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m_last_timestamp = newts; |
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prevts = pkt_ctr_ticks; |
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if (rep == 0) { |
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debugOutput(DEBUG_LEVEL_VERBOSE, " timestamp: %lld, ct=%08x (%03ld,%04ld,%04ld)\n", m_last_timestamp, pkt_ctr, |
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CYCLE_TIMER_GET_SECS(pkt_ctr), CYCLE_TIMER_GET_CYCLES(pkt_ctr), CYCLE_TIMER_GET_OFFSET(pkt_ctr)); |
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debugOutput(DEBUG_LEVEL_VERBOSE, " %02x %02x %02x %02x %02x %02x %02x %02x\n", |
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adata[0] & 0xff, adata[1] & 0xff, adata[2] & 0xff, adata[3] & 0xff, |
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adata[4] & 0xff, adata[5] & 0xff, adata[6] & 0xff, adata[7] & 0xff); |
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debugOutput(DEBUG_LEVEL_VERBOSE, " tx size=%d, rxcount=%d\n", |
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((adata[5] & 0xff) << 8) | (adata[0] & 0xff), |
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((adata[4] & 0xff) << 8) | (adata[1] & 0xff)); |
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n_hw_tx_buffer_samples = adata[7] & 0xff; |
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debugOutput(DEBUG_LEVEL_VERBOSE, " hw tx: 0x%02x\n", n_hw_tx_buffer_samples); |
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} |
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rep=1; |
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return eCRV_OK; |
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} else { |
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return eCRV_Invalid; |
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} |
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} |
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|
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/** |
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* extract the data from the packet |
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* @pre the IEC61883 packet is valid according to isValidPacket |
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* @param data |
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* @param length |
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* @param channel |
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* @param tag |
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* @param sy |
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* @param pkt_ctr |
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* @return |
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*/ |
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enum StreamProcessor::eChildReturnValue |
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RmeReceiveStreamProcessor::processPacketData(unsigned char *data, unsigned int length) { |
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// m_event_size should never be zero |
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unsigned int n_events = length / m_event_size; |
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|
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// for testing |
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static signed int rep = 0; |
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|
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// we have to keep in mind that there are also |
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// some packets buffered by the ISO layer, |
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// at most x=m_handler->getWakeupInterval() |
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// these contain at most x*syt_interval |
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// frames, meaning that we might receive |
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// this packet x*syt_interval*ticks_per_frame |
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// later than expected (the real receive time) |
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#ifdef DEBUG |
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if(isRunning()) { |
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debugOutput(DEBUG_LEVEL_VERY_VERBOSE,"STMP: %lluticks | tpf=%f\n", |
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m_last_timestamp, getTicksPerFrame()); |
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} |
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#endif |
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|
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// For testing |
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if (rep == 0) { |
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debugOutput(DEBUG_LEVEL_VERBOSE, "data packet data, length=%d, ev_size=%d, n_events=%d\n", length, m_event_size, n_events); |
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rep = 1; |
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} |
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if(m_data_buffer->writeFrames(n_events, (char *)data, m_last_timestamp)) { |
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return eCRV_OK; |
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} else { |
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return eCRV_XRun; |
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} |
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} |
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|
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/*********************************************** |
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* Encoding/Decoding API * |
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***********************************************/ |
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/** |
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* \brief write received events to the port ringbuffers. |
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*/ |
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bool RmeReceiveStreamProcessor::processReadBlock(char *data, |
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unsigned int nevents, unsigned int offset) |
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{ |
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bool no_problem=true; |
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for ( PortVectorIterator it = m_Ports.begin(); |
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it != m_Ports.end(); |
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++it ) { |
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if((*it)->isDisabled()) {continue;}; |
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|
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Port *port=(*it); |
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|
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switch(port->getPortType()) { |
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case Port::E_Audio: |
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if(decodeRmeEventsToPort(static_cast<RmeAudioPort *>(*it), (quadlet_t *)data, offset, nevents)) { |
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debugWarning("Could not decode packet data to port %s\n",(*it)->getName().c_str()); |
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no_problem=false; |
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} |
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break; |
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case Port::E_Midi: |
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if(decodeRmeMidiEventsToPort(static_cast<RmeMidiPort *>(*it), (quadlet_t *)data, offset, nevents)) { |
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debugWarning("Could not decode packet midi data to port %s\n",(*it)->getName().c_str()); |
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no_problem=false; |
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} |
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break; |
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|
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default: // ignore |
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break; |
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} |
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} |
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return no_problem; |
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} |
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|
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signed int RmeReceiveStreamProcessor::decodeRmeEventsToPort(RmeAudioPort *p, |
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quadlet_t *data, unsigned int offset, unsigned int nevents) |
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{ |
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unsigned int j=0; |
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|
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// For RME interfaces the audio data is contained in the most significant |
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// 24 bits of a 32-bit field. Thus it makes sense to treat the source |
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// data as 32 bit and simply mask/shift as necessary to isolate the |
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// audio data. |
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quadlet_t *src_data; |
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src_data = data + p->getPosition()/4; |
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|
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switch(m_StreamProcessorManager.getAudioDataType()) { |
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default: |
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case StreamProcessorManager::eADT_Int24: |
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{ |
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quadlet_t *buffer=(quadlet_t *)(p->getBufferAddress()); |
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|
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assert(nevents + offset <= p->getBufferSize()); |
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|
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// Offset is in frames, but each port is only a single |
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// channel, so the number of frames is the same as the |
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// number of quadlets to offset (assuming the port buffer |
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// uses one quadlet per sample, which is the case currently). |
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buffer+=offset; |
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|
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for(j = 0; j < nevents; j += 1) { // Decode nsamples |
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*buffer = (*src_data >> 8) & 0x00ffffff; |
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// Sign-extend highest bit of 24-bit int. This isn't |
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// strictly needed since E_Int24 is a 24-bit, but doing |
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// so shouldn't break anything and makes the data easier |
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// to deal with during debugging. |
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if (*src_data & 0x80000000) |
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*buffer |= 0xff000000; |
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|
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buffer++; |
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src_data+=m_event_size/4; |
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} |
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} |
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break; |
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case StreamProcessorManager::eADT_Float: |
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{ |
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const float multiplier = 1.0f / (float)(0x7FFFFF); |
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float *buffer=(float *)(p->getBufferAddress()); |
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|
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assert(nevents + offset <= p->getBufferSize()); |
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|
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buffer+=offset; |
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|
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for(j = 0; j < nevents; j += 1) { // decode max nsamples |
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signed int v = (*src_data >> 8) & 0x00ffffff; |
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/* Sign-extend highest bit of incoming 24-bit integer */ |
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if (*src_data & 0x80000000) |
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v |= 0xff000000; |
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*buffer = v * multiplier; |
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buffer++; |
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src_data+=m_event_size/4; |
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} |
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} |
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break; |
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} |
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|
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return 0; |
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} |
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398 |
|
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399 |
int |
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400 |
RmeReceiveStreamProcessor::decodeRmeMidiEventsToPort( |
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401 |
RmeMidiPort *p, quadlet_t *data, |
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402 |
unsigned int offset, unsigned int nevents) |
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403 |
{ |
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404 |
unsigned int j = 0; |
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405 |
unsigned char *src = NULL; |
---|
406 |
|
---|
407 |
quadlet_t *buffer = (quadlet_t *)(p->getBufferAddress()); |
---|
408 |
assert(nevents + offset <= p->getBufferSize()); |
---|
409 |
buffer += offset; |
---|
410 |
|
---|
411 |
// Zero the buffer |
---|
412 |
memset(buffer, 0, nevents*sizeof(*buffer)); |
---|
413 |
|
---|
414 |
// Get MIDI bytes if present in any frames within the packet. RME MIDI |
---|
415 |
// data is sent as part of a 3-byte sequence starting at the port's |
---|
416 |
// position. Some RMEs (eg: the 828MkII) send more than one MIDI byte |
---|
417 |
// in some packets. Since the FFADO MIDI layer requires a MIDI byte in |
---|
418 |
// only every 8th buffer position we allow for this by buffering the |
---|
419 |
// incoming data. The buffer is small since it only has to cover for |
---|
420 |
// short-term excursions in the data rate. Since the MIDI data |
---|
421 |
// originates on a physical MIDI bus the overall data rate is limited by |
---|
422 |
// the baud rate of that bus (31250), which is no more than one byte in |
---|
423 |
// 8 even for 1x sample rates. |
---|
424 |
src = (unsigned char *)data + p->getPosition(); |
---|
425 |
// We assume that the buffer has been set up in such a way that the first |
---|
426 |
// element is correctly aligned for FFADOs MIDI layer. The requirement |
---|
427 |
// is that actual MIDI bytes must be aligned to multiples of 8 samples. |
---|
428 |
|
---|
429 |
while (j < nevents) { |
---|
430 |
/* Most events don't have MIDI data bytes */ |
---|
431 |
// if (unlikely((*src & RME_KEY_MASK_MIDI) == RME_KEY_MASK_MIDI)) { |
---|
432 |
if (0) { |
---|
433 |
// A MIDI byte is in *(src+2). Bit 24 is used to flag MIDI data |
---|
434 |
// as present once the data makes it to the output buffer. |
---|
435 |
midibuffer[mb_head++] = 0x01000000 | *(src+2); |
---|
436 |
mb_head &= RX_MIDIBUFFER_SIZE-1; |
---|
437 |
if (unlikely(mb_head == mb_tail)) { |
---|
438 |
debugWarning("RME rx MIDI buffer overflow\n"); |
---|
439 |
/* Dump oldest byte. This overflow can only happen if the |
---|
440 |
* rate coming in from the hardware MIDI port grossly |
---|
441 |
* exceeds the official MIDI baud rate of 31250 bps, so it |
---|
442 |
* should never occur in practice. |
---|
443 |
*/ |
---|
444 |
mb_tail = (mb_tail + 1) & (RX_MIDIBUFFER_SIZE-1); |
---|
445 |
} |
---|
446 |
} |
---|
447 |
/* Write to the buffer if we're at an 8-sample boundary */ |
---|
448 |
if (unlikely(!(j & 0x07))) { |
---|
449 |
if (mb_head != mb_tail) { |
---|
450 |
*buffer = midibuffer[mb_tail++]; |
---|
451 |
mb_tail &= RX_MIDIBUFFER_SIZE-1; |
---|
452 |
} |
---|
453 |
buffer += 8; |
---|
454 |
} |
---|
455 |
j++; |
---|
456 |
src += m_event_size; |
---|
457 |
} |
---|
458 |
|
---|
459 |
return 0; |
---|
460 |
} |
---|
461 |
|
---|
462 |
} // end of namespace Streaming |
---|