lupio_ipi.cc

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#include "dev/lupio/lupio_ipi.hh"
 
#include "cpu/base.hh"
#include "debug/LupioIPI.hh"
#include "mem/packet_access.hh"
#include "params/LupioIPI.hh"
 
namespace gem5
{
 
LupioIPI::LupioIPI(const Params &params) :
    BasicPioDevice(params, params.pio_size),
    system(params.system),
    intType(params.int_type),
    nThread(params.num_threads)
{
    word.resize(nThread, 0);
 
    DPRINTF(LupioIPI, "LupioIPI initalized--number of CPUs: %d\n", nThread);
}
 
uint64_t
LupioIPI::lupioIPIRead(uint8_t addr, int size)
{
    int cpu = addr >> 2;
    uint32_t r = 0;
    // Reading automatically lowers corresponding IRQ
    r = word[cpu];
 
    auto tc = system->threads[cpu];
    tc->getCpuPtr()->clearInterrupt(tc->threadId(), intType, 0);
    // Also reset value after reading
    word[cpu] = 0;
 
    return r;
}
 
void
LupioIPI::lupioIPIWrite(uint8_t addr, uint64_t val64, int size)
{
    int cpu = addr >> 2;;
    uint32_t val = val64;
 
    word[cpu] = val;
 
    // Raise IRQ
    auto tc = system->threads[cpu];
 
    tc->getCpuPtr()->postInterrupt(tc->threadId(), intType, 0);
}
 
Tick
LupioIPI::read(PacketPtr pkt)
{
    Addr ipi_addr = pkt->getAddr() - pioAddr;
 
    DPRINTF(LupioIPI,
        "Read request - addr: %#x, size: %#x\n", ipi_addr, pkt->getSize());
 
    uint64_t read_val = lupioIPIRead(ipi_addr, pkt->getSize());
    DPRINTF(LupioIPI, "Packet Read: %#x\n", read_val);
    pkt->setUintX(read_val, byteOrder);
    pkt->makeResponse();
 
    return pioDelay;
}
 
Tick
LupioIPI::write(PacketPtr pkt)
{
    Addr ipi_addr = pkt->getAddr() - pioAddr;
 
    DPRINTF(LupioIPI, "Write register %#x value %#x\n", ipi_addr,
            pkt->getUintX(byteOrder));
 
    lupioIPIWrite(ipi_addr, pkt->getUintX(byteOrder), pkt->getSize());
    DPRINTF(LupioIPI, "Packet Write Value: %d\n", pkt->getUintX(byteOrder));
 
    pkt->makeResponse();
 
    return pioDelay;
}
} // namespace gem5