2017-03-12 07:10:51 +00:00

240 lines
7.1 KiB
C++

/*
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2016 Furrtek
*
* This file is part of PortaPack.
*
* 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, 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; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#include "audio_dma.hpp"
#include <cstdint>
#include <cstddef>
#include <array>
#include "hal.h"
#include "gpdma.hpp"
using namespace lpc43xx;
#include "portapack_dma.hpp"
namespace audio {
namespace dma {
constexpr uint32_t gpdma_ahb_master_peripheral = 1;
constexpr uint32_t gpdma_ahb_master_memory = 0;
constexpr uint32_t gpdma_ahb_master_lli_fetch = 0;
constexpr uint32_t gpdma_rx_peripheral = 0x9; /* I2S0 DMA request 1 */
constexpr uint32_t gpdma_rx_src_peripheral = gpdma_rx_peripheral;
constexpr uint32_t gpdma_rx_dest_peripheral = gpdma_rx_peripheral;
constexpr uint32_t gpdma_tx_peripheral = 0xa; /* I2S0 DMA request 2 */
constexpr uint32_t gpdma_tx_src_peripheral = gpdma_tx_peripheral;
constexpr uint32_t gpdma_tx_dest_peripheral = gpdma_tx_peripheral;
constexpr gpdma::channel::LLIPointer lli_pointer(const void* lli) {
return {
.lm = gpdma_ahb_master_lli_fetch,
.r = 0,
.lli = reinterpret_cast<uint32_t>(lli),
};
}
constexpr gpdma::channel::Control control_tx(const size_t transfer_bytes) {
return {
.transfersize = gpdma::buffer_words(transfer_bytes, 4),
.sbsize = 4, /* Burst size: 32 */
.dbsize = 4, /* Burst size: 32 */
.swidth = 2, /* Source transfer width: word (32 bits) */
.dwidth = 2, /* Destination transfer width: word (32 bits) */
.s = gpdma_ahb_master_memory,
.d = gpdma_ahb_master_peripheral,
.si = 1,
.di = 0,
.prot1 = 0,
.prot2 = 0,
.prot3 = 0,
.i = 1,
};
}
constexpr gpdma::channel::Config config_tx() {
return {
.e = 0,
.srcperipheral = gpdma_tx_src_peripheral,
.destperipheral = gpdma_tx_dest_peripheral,
.flowcntrl = gpdma::FlowControl::MemoryToPeripheral_DMAControl,
.ie = 1,
.itc = 1,
.l = 0,
.a = 0,
.h = 0,
};
}
constexpr gpdma::channel::Control control_rx(const size_t transfer_bytes) {
return {
.transfersize = gpdma::buffer_words(transfer_bytes, 4),
.sbsize = 4, /* Burst size: 32 */
.dbsize = 4, /* Burst size: 32 */
.swidth = 2, /* Source transfer width: word (32 bits) */
.dwidth = 2, /* Destination transfer width: word (32 bits) */
.s = gpdma_ahb_master_peripheral,
.d = gpdma_ahb_master_memory,
.si = 0,
.di = 1,
.prot1 = 0,
.prot2 = 0,
.prot3 = 0,
.i = 1,
};
}
constexpr gpdma::channel::Config config_rx() {
return {
.e = 0,
.srcperipheral = gpdma_rx_src_peripheral,
.destperipheral = gpdma_rx_dest_peripheral,
.flowcntrl = gpdma::FlowControl::PeripheralToMemory_DMAControl,
.ie = 1,
.itc = 1,
.l = 0,
.a = 0,
.h = 0,
};
}
/* TODO: Clean up terminology around "buffer", "transfer", "samples" */
constexpr size_t buffer_samples_log2n = 7;
constexpr size_t buffer_samples = (1 << buffer_samples_log2n);
constexpr size_t transfers_per_buffer_log2n = 2;
constexpr size_t transfers_per_buffer = (1 << transfers_per_buffer_log2n);
constexpr size_t transfer_samples = buffer_samples / transfers_per_buffer;
constexpr size_t transfers_mask = transfers_per_buffer - 1;
constexpr size_t buffer_bytes = buffer_samples * sizeof(sample_t);
constexpr size_t transfer_bytes = transfer_samples * sizeof(sample_t);
static std::array<sample_t, buffer_samples> buffer_tx;
static std::array<sample_t, buffer_samples> buffer_rx;
static std::array<gpdma::channel::LLI, transfers_per_buffer> lli_tx_loop;
static std::array<gpdma::channel::LLI, transfers_per_buffer> lli_rx_loop;
static constexpr auto& gpdma_channel_i2s0_tx = gpdma::channels[portapack::i2s0_tx_gpdma_channel_number];
static constexpr auto& gpdma_channel_i2s0_rx = gpdma::channels[portapack::i2s0_rx_gpdma_channel_number];
static volatile const gpdma::channel::LLI* tx_next_lli = nullptr;
static volatile const gpdma::channel::LLI* rx_next_lli = nullptr;
static void tx_transfer_complete() {
tx_next_lli = gpdma_channel_i2s0_tx.next_lli();
}
static void tx_error() {
disable();
}
static void rx_transfer_complete() {
rx_next_lli = gpdma_channel_i2s0_rx.next_lli();
}
static void rx_error() {
disable();
}
void init() {
gpdma_channel_i2s0_tx.set_handlers(tx_transfer_complete, tx_error);
gpdma_channel_i2s0_rx.set_handlers(rx_transfer_complete, rx_error);
// LPC_GPDMA->SYNC |= (1 << gpdma_rx_peripheral);
// LPC_GPDMA->SYNC |= (1 << gpdma_tx_peripheral);
}
static void configure_tx() {
const auto peripheral = reinterpret_cast<uint32_t>(&LPC_I2S0->TXFIFO);
const auto control_value = control_tx(transfer_bytes);
for(size_t i=0; i<lli_tx_loop.size(); i++) {
const auto memory = reinterpret_cast<uint32_t>(&buffer_tx[i * transfer_samples]);
lli_tx_loop[i].srcaddr = memory;
lli_tx_loop[i].destaddr = peripheral;
lli_tx_loop[i].lli = lli_pointer(&lli_tx_loop[(i + 1) % lli_tx_loop.size()]);
lli_tx_loop[i].control = control_value;
}
}
static void configure_rx() {
const auto peripheral = reinterpret_cast<uint32_t>(&LPC_I2S0->RXFIFO);
const auto control_value = control_rx(transfer_bytes);
for(size_t i=0; i<lli_rx_loop.size(); i++) {
const auto memory = reinterpret_cast<uint32_t>(&buffer_rx[i * transfer_samples]);
lli_rx_loop[i].srcaddr = peripheral;
lli_rx_loop[i].destaddr = memory;
lli_rx_loop[i].lli = lli_pointer(&lli_rx_loop[(i + 1) % lli_rx_loop.size()]);
lli_rx_loop[i].control = control_value;
}
}
void configure() {
configure_tx();
configure_rx();
}
void enable() {
const auto gpdma_config_tx = config_tx();
const auto gpdma_config_rx = config_rx();
gpdma_channel_i2s0_tx.configure(lli_tx_loop[0], gpdma_config_tx);
gpdma_channel_i2s0_rx.configure(lli_rx_loop[0], gpdma_config_rx);
gpdma_channel_i2s0_tx.enable();
gpdma_channel_i2s0_rx.enable();
}
void disable() {
gpdma_channel_i2s0_tx.disable();
gpdma_channel_i2s0_rx.disable();
}
buffer_t tx_empty_buffer() {
const auto next_lli = tx_next_lli;
if( next_lli ) {
const size_t next_index = next_lli - &lli_tx_loop[0];
const size_t free_index = (next_index + transfers_per_buffer - 2) & transfers_mask;
return { reinterpret_cast<sample_t*>(lli_tx_loop[free_index].srcaddr), transfer_samples };
} else {
return { nullptr, 0 };
}
}
buffer_t rx_empty_buffer() {
const auto next_lli = rx_next_lli;
if( next_lli ) {
const size_t next_index = next_lli - &lli_rx_loop[0];
const size_t free_index = (next_index + transfers_per_buffer - 2) & transfers_mask;
return { reinterpret_cast<sample_t*>(lli_rx_loop[free_index].destaddr), transfer_samples };
} else {
return { nullptr, 0 };
}
}
} /* namespace dma */
} /* namespace audio */