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
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 * terms below provided that you ensure that this notice is replicated
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 * modified or unmodified, in source code or in binary form.
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 * met: redistributions of source code must retain the above copyright
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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"
 
namespace gem5
{
 
SimpleUart::SimpleUart(const SimpleUartParams &p)
    : Uart(p, p.pio_size), byteOrder(p.byte_order), 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;
}
 
} // namespace gem5