xref: /gem5/src/systemc/ext/tlm_utils/multi_passthrough_initiator_socket.h

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#ifndef __SYSTEMC_EXT_TLM_UTILS_MULTI_PASSTHROUGH_INITIATOR_SOCKET_H__
#define __SYSTEMC_EXT_TLM_UTILS_MULTI_PASSTHROUGH_INITIATOR_SOCKET_H__

#include "tlm_utils/multi_socket_bases.h"

namespace tlm_utils
{

/*
This class implements a trivial multi initiator socket.
The triviality refers to the fact that the socket does not
do blocking to non-blocking or non-blocking to blocking conversions.

It allows to connect multiple targets to this socket.
The user has to register callbacks for the bw interface methods
he likes to use. The callbacks are basically equal to the bw interface
methods but carry an additional integer that indicates to which
index of this socket the calling target is connected.
*/
template <typename MODULE, unsigned int BUSWIDTH=32,
          typename TYPES=tlm::tlm_base_protocol_types, unsigned int N=0,
          sc_core::sc_port_policy POL=sc_core::SC_ONE_OR_MORE_BOUND>
class multi_passthrough_initiator_socket :
    public multi_init_base< BUSWIDTH, TYPES, N, POL>
{
  public:

    //typedefs
    //  tlm 2.0 types for nb_transport
    typedef typename TYPES::tlm_payload_type transaction_type;
    typedef typename TYPES::tlm_phase_type phase_type;
    typedef tlm::tlm_sync_enum sync_enum_type;

    //  typedefs to keep the fn ptr notations short
    typedef sync_enum_type (MODULE::*nb_cb)(
            int, transaction_type &, phase_type &, sc_core::sc_time &);
    typedef void (MODULE::*dmi_cb)(int, sc_dt::uint64, sc_dt::uint64);

    typedef multi_init_base<BUSWIDTH, TYPES, N, POL> base_type;

    typedef typename base_type::base_target_socket_type
        base_target_socket_type;

    static const char *
    default_name()
    {
        return sc_core::sc_gen_unique_name(
                "multi_passthrough_initiator_socket");
    }

    explicit multi_passthrough_initiator_socket(
            const char *name=default_name()) :
        base_type(name), m_hierarch_bind(nullptr), m_beoe_disabled(false),
        m_dummy(this, 42)
    {}

    ~multi_passthrough_initiator_socket()
    {
        // Clean up everything allocated by 'new'.
        for (unsigned int i = 0; i < m_binders.size(); i++)
            delete m_binders[i];
    }

    // Register callback for nb transport of bw interface.
    void
    register_nb_transport_bw(MODULE *mod, sync_enum_type (MODULE::*cb)(
                int, transaction_type &, phase_type &, sc_core::sc_time &))
    {
        // Warn if there already is a callback.
        if (m_nb_f.is_valid()) {
            display_warning("NBTransport_bw callback already registered.");
            return;
        }

        // Set the functor.
        m_nb_f.set_function(mod, cb);
    }

    // Register callback for dmi function of bw interface.
    void
    register_invalidate_direct_mem_ptr(MODULE *mod, void (MODULE::*cb)(
                int, sc_dt::uint64, sc_dt::uint64))
    {
        // Warn if there already is a callback.
        if (m_dmi_f.is_valid()) {
            display_warning("InvalidateDMI callback already registered.");
            return;
        }

        // Set the functor.
        m_dmi_f.set_function(mod, cb);
    }

    // Override virtual functions of the tlm_initiator_socket:
    // this function is called whenever an sc_port (as part of a target socket)
    // wants to bind to the export of the underlying tlm_initiator_socket.
    // At this time a callback binder is created an returned to the sc_port
    // of the target socket, so that it binds to the callback binder.
    virtual tlm::tlm_bw_transport_if<TYPES> &
    get_base_interface()
    {
        m_binders.push_back(
                new callback_binder_bw<TYPES>(this, m_binders.size()));
        return *m_binders[m_binders.size() - 1];
    }

    // Const overload not allowed for multi-sockets.
    virtual const tlm::tlm_bw_transport_if<TYPES> &
    get_base_interface() const
    {
        display_error("'get_base_interface()'"
                " const not allowed for multi-sockets.");
        return base_type::get_base_interface();
    }

    // Override virtual functions of the tlm_initiator_socket:
    // This function is called whenever an sc_export (as part of a initiator
    // socket) wants to bind to the export of the underlying
    // tlm_initiator_socket, i.e. a hierarchical bind takes place.
    virtual sc_core::sc_export<tlm::tlm_bw_transport_if<TYPES>> &
    get_base_export()
    {
        if (!m_beoe_disabled) { // We are not bound hierarchically.
            // So we bind the dummy to avoid a SystemC error.
            base_type::m_export.bind(m_dummy);
        }
        // and then return our own export so that the hierarchical
        // binding is set up properly.
        return base_type::get_base_export();
    }

    virtual const sc_core::sc_export<tlm::tlm_bw_transport_if<TYPES>> &
    get_base_export() const
    {
        return base_type::get_base_export();
    }

    // Bind against a target socket.
    virtual void
    bind(base_target_socket_type &s)
    {
        // Error if this socket is already bound hierarchically.
        if (m_hierarch_bind) {
            display_error("Already hierarchically bound.");
            return;
        }

        // Satisfy systemC, leads to a call to get_base_interface().
        base_type::bind(s);

        // Try to cast the target socket into a fw interface.
        sc_core::sc_export<tlm::tlm_fw_transport_if<TYPES>> *p_ex_s =
            dynamic_cast<sc_core::sc_export<
                tlm::tlm_fw_transport_if<TYPES>> *>(&s);
        if (!p_ex_s) {
            display_error("Multi socket not bound to tlm_socket.");
            return;
        }

        // Try a cast into a multi sockets.
        multi_to_multi_bind_base<TYPES> *test =
            dynamic_cast<multi_to_multi_bind_base<TYPES> *>(p_ex_s);
        if (test) {
            // Did we just do a multi-multi bind??
            // If that is the case the multi target socket must have just
            // created a callback binder which we want to get from it.
            // Moreover, we also just created one, which we will pass to it.
            m_sockets.push_back(test->get_last_binder(
                        m_binders[m_binders.size() - 1]));
        } else { // If not just bind normally,
            sc_core::sc_export<tlm::tlm_fw_transport_if<TYPES>> &ex_s =
                *p_ex_s;
            // Store the interface we are bound against.
            m_sockets.push_back(&((tlm::tlm_fw_transport_if<TYPES> &)ex_s));
        }
    }

    // Operator notation for direct bind.
    void operator() (base_target_socket_type &s) { bind(s); }

    // SystemC standard callback before end of elaboration.
    void
    before_end_of_elaboration()
    {
        // If our export hasn't been bound yet (due to a hierarch binding)
        // we bind it now to avoid a SystemC error. We must do that because it
        // is legal not to register a callback on this socket as the user
        // might only use b_transport.
        if (!base_type::m_export.get_interface()) {
            base_type::m_export.bind(m_dummy);
        }

        // 'break' here if the socket was told not to do callback binding.
        if (m_beoe_disabled)
            return;

        // Get the callback binders of the top of the hierachical bind chain.
        // NOTE: this could be the same socket if there is no hierachical bind.
        std::vector<callback_binder_bw<TYPES> *> &binders =
            get_hierarch_bind()->get_binders();

        // Get the interfaces bound to the top of the hierachical bind chain.
        // NOTE: this could be the same socket if there is no hierachical bind.
        m_used_sockets = get_hierarch_bind()->get_sockets();

        // Register the callbacks of this socket with the callback binders
        // we just got from the top of the hierachical bind chain.
        for (unsigned int i = 0; i < binders.size(); i++) {
            binders[i]->set_callbacks(m_nb_f, m_dmi_f);
        }
    }

    //
    // Bind multi initiator socket to multi initiator socket (hierarchical
    // bind).
    //
    virtual void
    bind(base_type& s)
    {
        if (m_binders.size()) {
            // A multi socket is either bound hierarchically or directly.
            display_error("Socket already directly bound.");
            return;
        }
        if (m_hierarch_bind) {
            display_warning("Socket already bound hierarchically. "
                    "Bind attempt ignored.");
            return;
        }

        // Remember to which socket we are hierarchically bound and disable it,
        // so that it won't try to register callbacks itself.
        s.disable_cb_bind();
        m_hierarch_bind = &s;
        base_type::bind(s); // Satisfy SystemC.
    }

    // Operator notation for hierarchical bind.
    void operator() (base_type &s) { bind(s); }

    // Get access to sub port.
    tlm::tlm_fw_transport_if<TYPES> *
    operator [] (int i)
    {
        return m_used_sockets[i];
    }

    // Get the number of bound targets.
    // NOTE: This is only valid at end of elaboration!
    unsigned int size() { return get_hierarch_bind()->get_sockets().size(); }

  protected:
    using base_type::display_warning;
    using base_type::display_error;

    // Implementation of base class interface.
    base_type *
    get_hierarch_bind()
    {
        if (m_hierarch_bind)
            return m_hierarch_bind->get_hierarch_bind();
        else
            return this;
    }
    void disable_cb_bind() { m_beoe_disabled = true; }
    std::vector<callback_binder_bw<TYPES> *> &
    get_binders()
    {
        return m_binders;
    }
    std::vector<tlm::tlm_fw_transport_if<TYPES> *> &
    get_sockets()
    {
        return m_sockets;
    }
    // Vector of connected sockets.
    std::vector<tlm::tlm_fw_transport_if<TYPES> *> m_sockets;
    std::vector<tlm::tlm_fw_transport_if<TYPES> *> m_used_sockets;
    // Vector of binders that convert untagged interface into tagged interface.
    std::vector<callback_binder_bw<TYPES> *> m_binders;

    base_type *m_hierarch_bind; // Pointer to hierarchical bound multi port.
    // bool that remembers whether this socket shall bind callbacks or not.
    bool m_beoe_disabled;
    // A callback binder that is bound to the underlying export
    // in case there was no real bind.
    callback_binder_bw<TYPES> m_dummy;

    //callbacks as functors
    // (allows to pass the callback to another socket that does not know the
    // type of the module that owns the callbacks).
    typename callback_binder_bw<TYPES>::nb_func_type m_nb_f;
    typename callback_binder_bw<TYPES>::dmi_func_type m_dmi_f;
};

template <typename MODULE, unsigned int BUSWIDTH=32,
          typename TYPES=tlm::tlm_base_protocol_types, unsigned int N=0>
class multi_passthrough_initiator_socket_optional :
    public multi_passthrough_initiator_socket<
        MODULE, BUSWIDTH, TYPES, N, sc_core::SC_ZERO_OR_MORE_BOUND>
{
    typedef multi_passthrough_initiator_socket<
        MODULE, BUSWIDTH, TYPES, N, sc_core::SC_ZERO_OR_MORE_BOUND> socket_b;
  public:
    multi_passthrough_initiator_socket_optional() : socket_b() {}
    explicit multi_passthrough_initiator_socket_optional(const char *name) :
        socket_b(name)
    {}
};

} // namespace tlm_utils

#endif /* __SYSTEMC_EXT_TLM_UTILS_MULTI_PASSTHROUGH_INITIATOR_SOCKET_H__ */