bus.cc

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#include "dev/pci/bus.hh"
 
#include "debug/AddrRanges.hh"
#include "mem/noncoherent_xbar.hh"
#include "params/PciBus.hh"
 
namespace gem5
{
 
PciBus::PciBus(const Params &p) : NoncoherentXBar(p)
{
    // create a default port that will be used for configuration cycles
    configErrorPortID = memSidePorts.size();
    std::string portName = name() + ".config_error_port";
    RequestPort *bp =
        new NoncoherentXBarRequestPort(portName, *this, configErrorPortID);
    memSidePorts.push_back(bp);
    reqLayers.push_back(
        new ReqLayer(*bp, *this, csprintf("reqLayer%d", configErrorPortID)));
}
 
Port &
PciBus::getPort(const std::string &if_name, PortID idx)
{
    if (if_name == "config_error_port") {
        return *memSidePorts[configErrorPortID];
    } else {
        return NoncoherentXBar::getPort(if_name, idx);
    }
}
 
void
PciBus::recvRangeChange(PortID mem_side_port_id)
{
    if (mem_side_port_id == configErrorPortID) {
        // Configuration port is used as a default port for a give range. It
        // doesn't require any check for overlapping ranges and isn't needed
        // for gotAllAddrRanges.
        configRange = memSidePorts[mem_side_port_id]->getAddrRanges();
        DPRINTF(AddrRanges, "Got new config range: %s\n",
                configRange.to_string());
    } else {
        NoncoherentXBar::recvRangeChange(mem_side_port_id);
    }
}
 
PortID
PciBus::findPort(AddrRange addr_range, PacketPtr pkt)
{
    PortID port_id = NoncoherentXBar::findPort(addr_range, pkt);
 
    // Configuration error port overrides default port for a given range.
    if (port_id == defaultPortID && addr_range.isSubset(configRange)) {
        return configErrorPortID;
    }
 
    return port_id;
}
 
} // namespace gem5