RubyPort.hh revision 6844:b8421af116e5 
1#ifndef RUBYPORT_H
2#define RUBYPORT_H
3
4#include "mem/ruby/libruby.hh"
5#include <string>
6#include <assert.h>
7
8using namespace std;
9
10class RubyPort {
11public:
12  RubyPort(const string & name)
13    : m_name(name)
14  {
15    m_port_id = m_num_ports++;
16    m_request_cnt = 0;
17    m_hit_callback = NULL;
18    assert(m_num_ports <= 2048); // see below for reason
19  }
20  virtual ~RubyPort() {}
21
22  virtual int64_t makeRequest(const RubyRequest & request) = 0;
23
24  void registerHitCallback(void (*hit_callback)(int64_t request_id)) {
25    assert(m_hit_callback == NULL); // can't assign hit_callback twice
26    m_hit_callback = hit_callback;
27  }
28
29protected:
30  const string m_name;
31  void (*m_hit_callback)(int64_t);
32
33  int64_t makeUniqueRequestID() {
34    // The request ID is generated by combining the port ID with a request count
35    // so that request IDs can be formed concurrently by multiple threads.
36    // IDs are formed as follows:
37    //
38    //
39    //   0        PortID                         Request Count
40    // +----+---------------+-----------------------------------------------------+
41    // | 63 |     62-48     |                         47-0                        |
42    // +----+---------------+-----------------------------------------------------+
43    //
44    //
45    //  This limits the system to a maximum of 2^11 == 2048 components
46    //  and 2^48 ~= 3x10^14 requests per component
47
48    int64_t id = (static_cast<uint64_t>(m_port_id) << 48) | m_request_cnt;
49    m_request_cnt++;
50    // assert((m_request_cnt & (1<<48)) == 0);
51    return id;
52  }
53
54private:
55  static uint16_t m_num_ports;
56  uint16_t m_port_id;
57  uint64_t m_request_cnt;
58};
59
60#endif
61