src/systemc/ext/tlm_core/2/interfaces/dmi.hh

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  more contributor license agreements.  See the NOTICE file distributed
  with this work for additional information regarding copyright ownership.
  Accellera licenses this file to you under the Apache License, Version 2.0
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#ifndef __SYSTEMC_EXT_TLM_CORE_2_INTERFACES_DMI_HH__
#define __SYSTEMC_EXT_TLM_CORE_2_INTERFACES_DMI_HH__

#include "../../../core/sc_time.hh"
#include "../../../dt/int/sc_nbdefs.hh"

namespace tlm
{

class tlm_dmi
{
  public:
    // Enum for indicating the access granted to the initiator.
    // The initiator uses gp.m_command to indicate it intention (read/write)
    //  The target is allowed to promote DMI_ACCESS_READ or DMI_ACCESS_WRITE
    //  requests to dmi_access_read_write.

    enum dmi_access_e {
        DMI_ACCESS_NONE = 0x00, // no access
        DMI_ACCESS_READ = 0x01, // read access
        DMI_ACCESS_WRITE = 0x02, // write access
        DMI_ACCESS_READ_WRITE = DMI_ACCESS_READ | DMI_ACCESS_WRITE
            // read/write access
    };

    tlm_dmi() { init(); }

    void
    init()
    {
        m_dmi_ptr = nullptr;
        m_dmi_start_address = 0x0;
        m_dmi_end_address = (sc_dt::uint64)(-1);
        m_dmi_access = DMI_ACCESS_NONE;
        m_dmi_read_latency = sc_core::SC_ZERO_TIME;
        m_dmi_write_latency = sc_core::SC_ZERO_TIME;
    }

    unsigned char *get_dmi_ptr() const { return m_dmi_ptr; }
    sc_dt::uint64 get_start_address() const { return m_dmi_start_address; }
    sc_dt::uint64 get_end_address() const { return m_dmi_end_address; }
    sc_core::sc_time get_read_latency() const { return m_dmi_read_latency; }
    sc_core::sc_time get_write_latency() const { return m_dmi_write_latency; }
    dmi_access_e get_granted_access() const { return m_dmi_access; }
    bool is_none_allowed() const { return m_dmi_access == DMI_ACCESS_NONE; }
    bool
    is_read_allowed() const
    {
        return (m_dmi_access & DMI_ACCESS_READ) == DMI_ACCESS_READ;
    }
    bool
    is_write_allowed() const
    {
        return (m_dmi_access & DMI_ACCESS_WRITE) == DMI_ACCESS_WRITE;
    }
    bool
    is_read_write_allowed() const
    {
        return (m_dmi_access & DMI_ACCESS_READ_WRITE) == DMI_ACCESS_READ_WRITE;
    }

    void set_dmi_ptr(unsigned char *p) { m_dmi_ptr = p; }
    void set_start_address(sc_dt::uint64 addr) { m_dmi_start_address = addr; }
    void set_end_address(sc_dt::uint64 addr) { m_dmi_end_address = addr; }
    void set_read_latency(sc_core::sc_time t) { m_dmi_read_latency = t; }
    void set_write_latency(sc_core::sc_time t) { m_dmi_write_latency = t; }
    void set_granted_access(dmi_access_e a) { m_dmi_access = a; }
    void allow_none() { m_dmi_access = DMI_ACCESS_NONE; }
    void allow_read() { m_dmi_access = DMI_ACCESS_READ; }
    void allow_write() { m_dmi_access = DMI_ACCESS_WRITE; }
    void allow_read_write() { m_dmi_access = DMI_ACCESS_READ_WRITE; }

  private:
    // If the forward call is successful, the target returns the dmi_ptr,
    // which must point to the data element corresponding to the
    // dmi_start_address. The data is organized as a byte array with the
    // endianness of the target (endianness member of the tlm_dmi struct).

    unsigned char *m_dmi_ptr;

    // The absolute start and end addresses of the DMI region. If the decoder
    // logic in the interconnect changes the address field e.g. by masking, the
    // interconnect is responsible to transform the relative address back to an
    // absolute address again.

    sc_dt::uint64 m_dmi_start_address;
    sc_dt::uint64 m_dmi_end_address;

    // Granted access

    dmi_access_e m_dmi_access;

    // These members define the latency of read/write transactions. The
    // initiator must initialize these members to zero before requesting a
    // dmi pointer, because both the interconnect as well as the target can
    // add to the total transaction latency.
    // Depending on the 'type' attribute only one, or both of these attributes
    // will be valid.

    sc_core::sc_time m_dmi_read_latency;
    sc_core::sc_time m_dmi_write_latency;
};

} // namespace tlm

#endif /* __SYSTEMC_EXT_TLM_CORE_2_INTERFACES_DMI_HH__ */