Initial firmware commit.

firmware/common/gpdma.cpp

@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
+ *
+ * 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 "gpdma.hpp"
+
+#include <array>
+
+namespace lpc43xx {
+namespace gpdma {
+
+namespace {
+
+struct ChannelHandlers {
+	TCHandler tc;
+	ErrHandler err;
+
+	constexpr ChannelHandlers(
+	) : tc(nullptr),
+		err(nullptr)
+	{
+	}
+};
+
+}
+
+static std::array<ChannelHandlers, channels.size()> handlers_table { {} };
+
+namespace channel {
+
+void Channel::set_handlers(const TCHandler tc_handler, const ErrHandler err_handler) const {
+	handlers_table[number].tc = tc_handler;
+	handlers_table[number].err = err_handler;
+}
+
+void Channel::configure(
+	const LLI& first_lli,
+	const uint32_t config
+) const {
+	disable_force();
+	clear_interrupts();
+
+	LPC_GPDMA_Channel_Type* const channel = &LPC_GPDMA->CH[number];
+	channel->SRCADDR = first_lli.srcaddr;
+	channel->DESTADDR = first_lli.destaddr;
+	channel->LLI = first_lli.lli;
+	channel->CONTROL = first_lli.control;
+	channel->CONFIG = config;
+}
+
+} /* namespace channel */
+
+extern "C" {
+
+LOCATE_IN_RAM
+CH_IRQ_HANDLER(DMA_IRQHandler) {
+	CH_IRQ_PROLOGUE();
+
+	chSysLockFromIsr();
+
+	const auto tc_stat = LPC_GPDMA->INTTCSTAT;
+	/* TODO: Service the higher channel numbers first, they're higher priority
+	 * right?!?
+	 */
+	for(size_t i=0; i<handlers_table.size(); i++) {
+		if( (tc_stat >> i) & 1 ) {
+			if( handlers_table[i].tc ) {
+				handlers_table[i].tc();
+			}
+		}
+	}
+	LPC_GPDMA->INTTCCLR = tc_stat;
+
+	/* Test for *any* error first, before looping, since errors should be
+	 * exceptional and we should spend as little time on them in the common
+	 * case.
+	 */
+	const auto err_stat = LPC_GPDMA->INTERRSTAT;
+	if( err_stat ) {
+		for(size_t i=0; i<handlers_table.size(); i++) {
+			if( (err_stat >> i) & 1 ) {
+				if( handlers_table[i].err ) {
+					handlers_table[i].err();
+				}
+			}
+		}
+		LPC_GPDMA->INTERRCLR = err_stat;
+	}
+
+	chSysUnlockFromIsr();
+
+	CH_IRQ_EPILOGUE();
+}
+}
+
+} /* namespace gpdma */
+} /* namespace lpc43xx */