initially add simple lt_bus

5 files changed, 386 insertions, 3 deletions

diff --git a/.clang-format b/.clang-format
index 3234cd9..ea403fe 100644
--- a/.clang-format
+++ b/.clang-format
@@ -1,5 +1,5 @@
 ---
-Language:        Cpp
+Language:      Cpp
 BasedOnStyle:  Chromium
 
 AllowShortFunctionsOnASingleLine: Empty
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8e3d7fd..6db84fe 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,7 +7,7 @@ find_package(SystemCLanguage CONFIG REQUIRED)
 # Set CXX std based on SystemC configuration.
 set (CMAKE_CXX_STANDARD ${SystemC_CXX_STANDARD} CACHE STRING "C++ standard to build all targets.")
 
-foreach (X IN ITEMS event sc_export sc_export2 minimal_socket browse)
+foreach (X IN ITEMS event sc_export sc_export2 minimal_socket browse lt_bus)
     add_executable(${X} src/${X}.cc)
     target_link_libraries(${X} SystemC::systemc)
 endforeach()
diff --git a/src/lt_bus.cc b/src/lt_bus.cc
new file mode 100644
index 0000000..078a8d8
--- /dev/null
+++ b/src/lt_bus.cc
@@ -0,0 +1,85 @@
+#include "models/lt_bus.h"
+#include "utils.h"
+
+#include <tlm_utils/simple_initiator_socket.h>
+#include <tlm_utils/simple_target_socket.h>
+
+// -- TARGET -------------------------------------------------------------------
+
+struct target : public sc_core::sc_module {
+  explicit target(sc_core::sc_module_name nm) : sc_module(std::move(nm)) {
+    p_sock.register_b_transport(this, &target::b_transport);
+  }
+
+  tlm_utils::simple_target_socket<target> p_sock{"sock"};
+
+ private:
+  void b_transport(tlm::tlm_generic_payload& tx, sc_core::sc_time& t) {
+    LOGM("transport 0x%llx w: %d r: %d", tx.get_address(), tx.is_write(),
+         tx.is_read());
+    tx.set_response_status(tlm::TLM_OK_RESPONSE);
+  }
+};
+
+// -- INITIATOR ----------------------------------------------------------------
+
+struct initiator : public sc_core::sc_module {
+  SC_HAS_PROCESS(initiator);
+
+  explicit initiator(sc_core::sc_module_name nm) : sc_module(std::move(nm)) {
+    SC_THREAD(run);
+  }
+
+  tlm_utils::simple_initiator_socket<initiator> p_sock{"sock"};
+
+ private:
+  void send_tx(tlm::tlm_command cmd, std::uint64_t addr) {
+    unsigned char data[4];
+    tlm::tlm_generic_payload tx;
+    tx.set_command(cmd);
+    tx.set_address(addr);
+    tx.set_data_ptr(data);
+    tx.set_data_length(sizeof(data));
+    tx.set_byte_enable_ptr(nullptr);
+    tx.set_byte_enable_length(0);
+    tx.set_response_status(tlm::TLM_INCOMPLETE_RESPONSE);
+    tx.set_dmi_allowed(false);
+
+    sc_core::sc_time t;
+    p_sock->b_transport(tx, t);
+
+    LOGM("ACCESS @%lx ok: %d (%s)", addr, tx.is_response_ok(),
+         tx.get_response_string().c_str());
+  }
+
+  void run() {
+    send_tx(tlm::TLM_WRITE_COMMAND, 0x1000);
+    send_tx(tlm::TLM_WRITE_COMMAND, 0x3000);
+    send_tx(tlm::TLM_WRITE_COMMAND, 0x4000);
+    send_tx(tlm::TLM_WRITE_COMMAND, 0x9000);
+    send_tx(tlm::TLM_WRITE_COMMAND, 0x80fc);
+    send_tx(tlm::TLM_WRITE_COMMAND, 0x80fd);
+  }
+};
+
+// -- SC_MAIN ------------------------------------------------------------------
+
+extern "C" int sc_main(int, char*[]) {
+  lt_bus bus{"bus"};
+
+  target target1{"target1"};
+  target target2{"target2"};
+  target target3{"target3"};
+
+  initiator init1{"init1"};
+
+  bus.attach_target(target2.p_sock, 0x4000, 0x4fff);
+  bus.attach_target(target1.p_sock, 0x0000, 0x3fff);
+  bus.attach_target(target3.p_sock, 0x8000, 0x80ff);
+
+  bus.attach_initiator(init1.p_sock);
+
+  sc_core::sc_start();
+
+  return 0;
+}
diff --git a/src/models/lt_bus.h b/src/models/lt_bus.h
new file mode 100644
index 0000000..9ae66b0
--- /dev/null
+++ b/src/models/lt_bus.h
@@ -0,0 +1,298 @@
+#ifndef SYSC_PLAYGROUND_LT_BUS
+#define SYSC_PLAYGROUND_LT_BUS
+
+#include <tlm_core/tlm_2/tlm_generic_payload/tlm_generic_payload.h>
+#include <tlm_core/tlm_2/tlm_sockets/tlm_sockets.h>
+
+#include <algorithm>
+#include <cstdint>
+#include <memory>
+#include <vector>
+
+struct scoped_push_hierarchy {
+  [[nodiscard]] explicit scoped_push_hierarchy(sc_core::sc_module& mod)
+      : m_mod(mod), m_simctx(sc_core::sc_get_curr_simcontext()) {
+    assert(m_simctx);
+    m_simctx->hierarchy_push(&m_mod);
+  }
+
+  ~scoped_push_hierarchy() {
+    const auto* top = m_simctx->hierarchy_pop();
+    assert(top == &m_mod);
+  }
+
+ private:
+  sc_core::sc_simcontext* m_simctx{nullptr};
+  sc_core::sc_module& m_mod;
+};
+
+struct range {
+  constexpr explicit range(std::uint64_t start, std::uint64_t end)
+      : start{start}, end{end} {
+    assert(start < end);
+  }
+
+  constexpr bool overlaps(range rhs) const {
+    return start <= rhs.end && rhs.start <= end;
+  }
+
+  constexpr bool contains(range rhs) const {
+    return start <= rhs.start && rhs.end <= end;
+  }
+
+  std::uint64_t start;
+  std::uint64_t end;
+};
+
+template <typename Module>
+class tlm_target_socket_tagged : public tlm::tlm_target_socket<>,
+                                 public tlm::tlm_fw_transport_if<> {
+  using cb_b_transport = void (Module::*)(std::size_t,
+                                          tlm::tlm_generic_payload&,
+                                          sc_core::sc_time&);
+
+  using cb_get_direct_mem_ptr = bool (Module::*)(std::size_t,
+                                                 tlm::tlm_generic_payload&,
+                                                 tlm::tlm_dmi&);
+  using cb_transport_dbg = unsigned int (Module::*)(std::size_t,
+                                                    tlm::tlm_generic_payload&);
+
+ public:
+  explicit tlm_target_socket_tagged(const char* name,
+                                    std::size_t id,
+                                    Module* mod,
+                                    cb_b_transport b,
+                                    cb_get_direct_mem_ptr m,
+                                    cb_transport_dbg d)
+      : tlm_target_socket<>{name},
+        m_mod{mod},
+        m_id{id},
+        m_b_transport{b},
+        m_get_direct_mem_ptr{m},
+        m_transport_dbg{d} {
+    bind(*static_cast<tlm::tlm_fw_transport_if<>*>(this));
+  }
+
+ private:
+  // -- TLM_FW_TRANSPORT_IF ----------------------------------------------------
+
+  virtual void b_transport(tlm::tlm_generic_payload& tx,
+                           sc_core::sc_time& t) override {
+    return (m_mod->*m_b_transport)(m_id, tx, t);
+  }
+
+  virtual bool get_direct_mem_ptr(tlm::tlm_generic_payload& tx,
+                                  tlm::tlm_dmi& dmi_data) override {
+    return (m_mod->*m_get_direct_mem_ptr)(m_id, tx, dmi_data);
+  }
+
+  virtual unsigned int transport_dbg(tlm::tlm_generic_payload& tx) override {
+    return (m_mod->*m_transport_dbg)(m_id, tx);
+  }
+
+  virtual tlm::tlm_sync_enum nb_transport_fw(tlm::tlm_generic_payload& tx,
+                                             tlm::tlm_phase& phase,
+                                             sc_core::sc_time& t) override {
+    std::fprintf(stderr,
+                 "tlm_target_socket_tagged: nb_transport_fw not supported\n");
+    std::abort();
+  }
+
+  // -- MEMBER -----------------------------------------------------------------
+
+  std::size_t m_id{0};
+  Module* m_mod{nullptr};
+  cb_b_transport m_b_transport{nullptr};
+  cb_get_direct_mem_ptr m_get_direct_mem_ptr{nullptr};
+  cb_transport_dbg m_transport_dbg{nullptr};
+};
+
+class lt_bus : public sc_core::sc_module, public tlm::tlm_bw_transport_if<> {
+  using target_socket = tlm_target_socket_tagged<lt_bus>;
+  using target_socket_ptr = std::unique_ptr<target_socket>;
+
+  using initiator_socket = tlm::tlm_initiator_socket<>;
+  using initiator_socket_ptr = std::unique_ptr<initiator_socket>;
+
+ public:
+  explicit lt_bus(sc_core::sc_module_name nm)
+      : sc_core::sc_module(std::move(nm)) {}
+
+  // -- ATTACH BUS INITIATOR ---------------------------------------------------
+
+  void attach_initiator(tlm::tlm_base_initiator_socket_b<>& init) {
+    const std::size_t id = m_initiators.size();
+    const std::string name = "init" + std::to_string(id);
+    {
+      // Add current module on top of module stack for tlm sockets.
+      scoped_push_hierarchy g(*this);
+
+      // Add new target socket to connect BUS INITIATOR.
+      m_initiators.push_back(std::make_unique<target_socket>(
+          name.c_str(), id, this, &lt_bus::b_transport,
+          &lt_bus::get_direct_mem_ptr, &lt_bus::transport_dbg));
+    }
+
+    // Bind sockets.
+    auto& target = m_initiators.back();
+    target->bind(init);
+  }
+
+  // -- ATTACH BUS TARGET ------------------------------------------------------
+
+  void attach_target(tlm::tlm_base_target_socket_b<>& target,
+                     std::uint64_t start,
+                     std::uint64_t end) {
+    const range addr{start, end};
+
+    // Check if new range overlaps with any registered memory map range.
+    for (const auto& map : m_mappings) {
+      if (map.addr.overlaps(addr)) {
+        std::fprintf(stderr,
+                     "lt_bus: memory map conflict detected\n"
+                     "old: %08lx - %08lx\n"
+                     "new: %08lx - %08lx\n",
+                     map.addr.start, map.addr.end, start, end);
+        std::abort();
+      }
+    }
+
+    const std::size_t id = m_targets.size();
+    const std::string name = "target" + std::to_string(id);
+    {
+      // Add current module on top of module stack for tlm sockets.
+      scoped_push_hierarchy g(*this);
+
+      // Add new initiator socket to connect BUS TARGET.
+      m_targets.push_back(std::make_unique<initiator_socket>(name.c_str()));
+    }
+
+    // Bind sockets.
+    auto& init = m_targets.back();
+    init->bind(*this);
+    init->bind(target);
+
+    // Insert new mapping, id is equal to idx into socket vector.
+    m_mappings.push_back({addr, id});
+  }
+
+ private:
+  // -- TLM_BW_TRANSPORT_IF ----------------------------------------------------
+
+  virtual tlm::tlm_sync_enum nb_transport_bw(tlm::tlm_generic_payload&,
+                                             tlm::tlm_phase&,
+                                             sc_core::sc_time&) override {
+    std::fprintf(stderr, "lt_bus: nb_transport_bw not supported\n");
+    std::abort();
+  }
+
+  virtual void invalidate_direct_mem_ptr(sc_dt::uint64 start,
+                                         sc_dt::uint64 end) override {
+    assert(false);
+  }
+
+  // -- TLM_FW_TRANSPORT_IF ----------------------------------------------------
+
+  void b_transport(std::size_t id,
+                   tlm::tlm_generic_payload& tx,
+                   sc_core::sc_time& t) {
+    std::uint64_t start = tx.get_address();
+    std::uint64_t end = start + tx.get_data_length() - 1;
+
+    if (auto res = decode(range{start, end})) {
+      assert(res.base <= start);
+
+      tx.set_address(start - res.base);
+      (*res.sock)->b_transport(tx, t);
+      tx.set_address(start);
+    } else {
+      tx.set_response_status(tlm::TLM_ADDRESS_ERROR_RESPONSE);
+    }
+  }
+
+  bool get_direct_mem_ptr(std::size_t,
+                          tlm::tlm_generic_payload& tx,
+                          tlm::tlm_dmi& dmi) {
+    std::uint64_t start = tx.get_address();
+    std::uint64_t end = start + tx.get_data_length() - 1;
+
+    bool ret = false;
+    if (auto res = decode(range{start, end})) {
+      assert(res.base <= start);
+
+      tx.set_address(start - res.base);
+      ret = (*res.sock)->get_direct_mem_ptr(tx, dmi);
+      tx.set_address(start);
+    }
+    return ret;
+  }
+
+  unsigned int transport_dbg(std::size_t, tlm::tlm_generic_payload& tx) {
+    std::uint64_t start = tx.get_address();
+    std::uint64_t end = start + tx.get_data_length() - 1;
+
+    unsigned int ret = 0;
+    if (auto res = decode(range{start, end})) {
+      assert(res.base <= start);
+
+      tx.set_address(start - res.base);
+      ret = (*res.sock)->transport_dbg(tx);
+      tx.set_address(start);
+    }
+    return ret;
+  }
+
+  // -- DECODE BUS TARGET ------------------------------------------------------
+
+  struct decode_result {
+    initiator_socket* sock{nullptr};
+    std::uint64_t base;
+
+    constexpr explicit operator bool() const {
+      return sock != nullptr;
+    }
+  };
+
+  decode_result decode(range addr) const {
+    for (const auto& map : m_mappings) {
+      if (map.addr.contains(addr)) {
+        return {m_targets[map.idx].get(), map.addr.start};
+      }
+    }
+    return {nullptr, 0ull};
+  }
+
+  // -- SC_MODULE CALLBACKS ----------------------------------------------------
+
+  virtual void start_of_simulation() override {
+    // Sort memory mappings by start address.
+    std::sort(m_mappings.begin(), m_mappings.end(),
+              [](const mapping& lhs, const mapping& rhs) {
+                return lhs.addr.start < rhs.addr.start;
+              });
+
+    // Dump memory map.
+    // for (const auto& map : m_mappings) {
+    //   std::printf("%08lx - %08lx :[%2ld] %s\n", map.addr.start, map.addr.end,
+    //               map.idx, m_targets[map.idx].get()->name());
+    // }
+  }
+
+  // -- LOCAL CLASSES ----------------------------------------------------------
+
+  struct mapping {
+    range addr;
+    std::size_t idx;
+  };
+
+  // -- MEMBER -----------------------------------------------------------------
+
+  // TARGET sockets to bind BUS INITIATORS against.
+  std::vector<target_socket_ptr> m_initiators;
+  // INITIATOR sockets to bind BUS TARGET against.
+  std::vector<initiator_socket_ptr> m_targets;
+  // Address range mappings to BUS TARGETs (m_tragets).
+  std::vector<mapping> m_mappings;
+};
+
+#endif
diff --git a/src/utils.h b/src/utils.h
index 5584027..1373b90 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -5,7 +5,7 @@
 
 #define LOG(FMT, ...)                                                     \
   do {                                                                    \
-    std::fprintf(stderr, "%10s | %4lld:%2lld | %10s | " FMT "\n",         \
+    std::fprintf(stderr, "%10s | %4lld:%2lld | %12s | " FMT "\n",         \
                  sc_core::sc_time_stamp().to_string().c_str(),            \
                  sc_core::sc_delta_count(),                               \
                  sc_core::sc_delta_count_at_current_time(), __FUNCTION__, \