simple.cc

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/*
 * Copyright (c) 2018 ARM Limited
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 *
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 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
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#include "dev/serial/simple.hh"

#include "mem/packet.hh"
#include "mem/packet_access.hh"
#include "params/SimpleUart.hh"
#include "sim/sim_exit.hh"

SimpleUart::SimpleUart(const SimpleUartParams *p)
    : Uart(p, p->pio_size),
      byteOrder(p->big_endian ? BigEndianByteOrder : LittleEndianByteOrder),
      endOnEOT(p->end_on_eot)
{
}

Tick
SimpleUart::read(PacketPtr pkt)
{
    assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);

    uint64_t data = 0;

    if (device->dataAvailable())
        data = device->readData();

    pkt->setUintX(data, byteOrder);

    pkt->makeAtomicResponse();
    return pioDelay;
}

Tick
SimpleUart::write(PacketPtr pkt)
{

    assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);

    uint8_t data = (uint8_t)pkt->getUintX(byteOrder);
    if (data == 0x04 && endOnEOT)
        exitSimLoop("UART received EOT", 0);

    device->writeData(data);

    pkt->makeAtomicResponse();
    return pioDelay;
}

SimpleUart *
SimpleUartParams::create()
{
    return new SimpleUart(this);
}