dft: per-chain enables, user-configurable name patterns

.gitignore

@@ -19,6 +19,7 @@ TAGS
 .cache
 Makefile
 __pycache__
+venv/
 
 include/ord/Version.hh
 

src/dft/CMakeLists.txt

@@ -70,6 +70,7 @@ target_link_libraries(dft
     dft_config_lib
     dft_replace_lib
     dft_clock_domain_lib
+    dft_reset_domain_lib
     dft_utils_lib
     dft_stitch_lib
 )
@@ -105,6 +106,7 @@ add_subdirectory(src/cells)
 add_subdirectory(src/clock_domain)
 add_subdirectory(src/config)
 add_subdirectory(src/replace)
+add_subdirectory(src/reset_domain)
 add_subdirectory(src/stitch)
 add_subdirectory(src/utils)
 if(ENABLE_TESTS)

src/dft/README.md

@@ -77,13 +77,51 @@ preview_dft
 
 ### Insert DFT
 
-Architect scan chains and connect them up in a way that minimises wirelength. As a result, this
-should be run after placement, and after `scan_replace`.
+Architect scan chains and connect them up in a way that minimises wirelength. As
+a result, this should be run after placement, and after `scan_replace`.
 
 ```tcl
 insert_dft
+    [-per_chain_enable]
+    [-scan_enable_name_pattern <string>]
+    [-scan_in_name_pattern <string>]
+    [-scan_out_name_pattern <string>]
 ```
 
+#### Options
+
+| Switch Name | Description |
+| ---- | ---- |
+| `-per_chain_enable` | Creates one enable signal per chain instead of reusing the same one for every chain. |
+| `-scan_enable_name_pattern` | A format pattern with exactly one set of braces (`{}`) to use to find or create scan enable drivers. The braces will be replaced with the chain's ordinal number (starting at `0`) if `-per_chain_enable` is defined, otherwise, all will share `0`. If an un-escaped forward slash (`/`) is found, instead of searching for and/or creating a top-level port, an instance's pin will be searched for instead where the part of the string preceding the `/` is interpreted as the instance name and part succeeding it will be interpreted as the pin's name. |
+| `-scan_in_name_pattern` | A format pattern with exactly one set of braces (`{}`) to use to find or create scan in drivers. The braces will be replaced with the chain's ordinal number (starting at `0`). If an un-escaped forward slash (`/`) is found, instead of searching for and/or creating a top-level port, an instance's pin will be searched for instead where the part of the string preceding the `/` is interpreted as the instance name and part succeeding it will be interpreted as the pin's name. |
+| `-scan_out_name_pattern` | A format pattern with exactly one set of braces (`{}`) to use to find or create scan in loads. The braces will be replaced with the chain's ordinal number (starting at `0`). If an un-escaped forward slash (`/`) is found, instead of searching for and/or creating a top-level port, an instance's pin will be searched for instead where the part of the string preceding the `/` is interpreted as the instance name and part succeeding it will be interpreted as the pin's name. |
+
+### Write Scan Chains
+
+Writes a JSON file containing metadata about the current architected scan chain.
+
+The JSON file is currently in this format:
+
+```jsonc
+{
+    "chain_0": {
+        "cells": [
+            "scanflop_0",
+            "scanflop_1",
+            "scanflop_2"
+        ]
+    },
+    /* … other chains … */ 
+}
+```
+
+…where the order of `.chain_name.cells` corresponds to the order of the elements
+in the scan-chain.
+
+```tcl
+write_scan_chains
+```
 
 ## Example scripts
 

src/dft/include/dft/Dft.hh

@@ -31,6 +31,8 @@
 // POSSIBILITY OF SUCH DAMAGE.
 #pragma once
 
+#include "ClockDomain.hh"
+#include "ResetDomain.hh"
 #include "db_sta/dbSta.hh"
 #include "odb/db.h"
 #include "utl/Logger.h"
@@ -95,7 +97,10 @@ class Dft
   //
   void scanReplace();
 
-  void insertDft();
+  void insertDft(bool per_chain_enable,
+                 const std::string& scan_enable_name_pattern,
+                 const std::string& scan_in_name_pattern,
+                 const std::string& scan_out_name_pattern);
 
   // Returns a mutable version of DftConfig
   DftConfig* getMutableDftConfig();
@@ -106,6 +111,9 @@ class Dft
   // Prints to stdout
   void reportDftConfig() const;
 
+  // Writes scan chains in a JSON format
+  void writeScanChains(const std::string& filename);
+
  private:
   // If we need to run pre_dft to create the internal state
   bool need_to_run_pre_dft_;

src/dft/src/Dft.cpp

@@ -32,6 +32,8 @@
 
 #include "dft/Dft.hh"
 
+#include <boost/property_tree/json_parser.hpp>
+#include <boost/property_tree/ptree.hpp>
 #include <iostream>
 
 #include "ClockDomain.hh"
@@ -104,15 +106,59 @@ void Dft::scanReplace()
   scan_replace_->scanReplace();
 }
 
-void Dft::insertDft()
+void Dft::writeScanChains(const std::string& filename)
+{
+  using boost::property_tree::ptree;
+  if (need_to_run_pre_dft_) {
+    pre_dft();
+  }
+
+  std::ofstream json_file(filename);
+  if (!json_file.is_open()) {
+    logger_->error(
+        utl::DFT, 13, "Failed to open file {} for writing.", filename);
+  }
+  try {
+    ptree root;
+
+    std::vector<std::unique_ptr<ScanChain>> scan_chains = scanArchitect();
+
+    for (auto& chain : scan_chains) {
+      ptree current_chain;
+      ptree cells;
+      auto& scan_cells = chain->getScanCells();
+      for (auto& cell : scan_cells) {
+        ptree name;
+        name.put("", cell->getName());
+        cells.push_back(std::make_pair("", name));
+      }
+      current_chain.add_child("cells", cells);
+      root.add_child(chain->getName(), current_chain);
+    }
+
+    boost::property_tree::write_json(json_file, root);
+  } catch (std::exception& ex) {
+    logger_->error(
+        utl::DFT, 14, "Failed to write JSON report. Exception: {}", ex.what());
+  }
+}
+
+void Dft::insertDft(bool per_chain_enable,
+                    const std::string& scan_enable_name_pattern,
+                    const std::string& scan_in_name_pattern,
+                    const std::string& scan_out_name_pattern)
 {
   if (need_to_run_pre_dft_) {
     pre_dft();
   }
   std::vector<std::unique_ptr<ScanChain>> scan_chains = scanArchitect();
 
-  ScanStitch stitch(db_);
-  stitch.Stitch(scan_chains);
+  ScanStitch stitch(db_,
+                    per_chain_enable,
+                    scan_enable_name_pattern,
+                    scan_in_name_pattern,
+                    scan_out_name_pattern);
+  stitch.Stitch(scan_chains, logger_);
 }
 
 DftConfig* Dft::getMutableDftConfig()

src/dft/src/architect/ScanChain.cpp

@@ -119,4 +119,9 @@ const std::string& ScanChain::getName() const
   return name_;
 }
 
+void ScanChain::rename(std::string& new_name)
+{
+  name_ = new_name;
+}
+
 }  // namespace dft

src/dft/src/architect/ScanChain.hh

@@ -85,6 +85,9 @@ class ScanChain
   // Returns the name of the scan chain
   const std::string& getName() const;
 
+  // Changes the name of the scan chain
+  void rename(std::string& new_name);
+
  private:
   std::string name_;
   std::vector<std::unique_ptr<ScanCell>> rising_edge_scan_cells_;

src/dft/src/cells/ScanCell.hh

@@ -127,8 +127,15 @@ class ScanCell
 
     odb::dbNet* driver_net = driver->getNet();
     if (!driver_net) {
-      driver_net = odb::dbNet::create(driver->getBlock(), GetTermName(driver));
+      driver_net = odb::dbNet::create(driver->getBlock(), driver->getName().c_str());
+      if (!driver_net) {
+        logger_->error(utl::DFT,
+                    30,
+                    "Failed to create driver net named '{}'",
+                    driver->getName());
+      }
       driver_net->setSigType(odb::dbSigType::SCAN);
+      driver->connect(driver_net);
     }
     debugPrint(logger_,
                utl::DFT,

src/dft/src/dft.i

@@ -38,6 +38,8 @@
 #include "DftConfig.hh"
 #include "ord/OpenRoad.hh"
 #include "ScanArchitect.hh"
+#include "ClockDomain.hh"
+#include "ResetDomain.hh"
 
 dft::Dft * getDft()
 {
@@ -51,6 +53,48 @@ utl::Logger* getLogger()
 
 %}
 
+%include "../../Exception.i"
+
+%typemap(typecheck) dft::ResetActiveEdge {
+  char *str = Tcl_GetStringFromObj($input, 0);
+    if (strcasecmp(str, "LOW") == 0) {
+    $1 = 1;
+  } else if (strcasecmp(str, "HIGH") == 0) {
+    $1 = 1;
+  } else {
+    $1 = 0;
+  }
+}
+
+%typemap(in) dft::ResetActiveEdge {
+  char *str = Tcl_GetStringFromObj($input, 0);
+  if (strcasecmp(str, "LOW") == 0) {
+    $1 = dft::ResetActiveEdge::Low;
+  } else /* other values eliminated in typecheck */ {
+    $1 = dft::ResetActiveEdge::High;
+  };
+}
+
+%typemap(typecheck) dft::ClockEdge {
+  char *str = Tcl_GetStringFromObj($input, 0);
+    if (strcasecmp(str, "RISING") == 0) {
+    $1 = 1;
+  } else if (strcasecmp(str, "FALLING") == 0) {
+    $1 = 1;
+  } else {
+    $1 = 0;
+  }
+}
+
+%typemap(in) dft::ClockEdge {
+  char *str = Tcl_GetStringFromObj($input, 0);
+  if (strcasecmp(str, "FALLING") == 0) {
+    $1 = dft::ClockEdge::Falling;
+  } else /* other values eliminated in typecheck */ {
+    $1 = dft::ClockEdge::Rising;
+  };
+}
+
 %inline
 %{
 
@@ -64,10 +108,18 @@ void scan_replace()
   getDft()->scanReplace();
 }
 
+void insert_dft(bool per_chain_enable,
+                const char* scan_enable_name_pattern,
+                const char* scan_in_name_pattern,
+                const char* scan_out_name_pattern)
+{
+  getDft()->insertDft(per_chain_enable, scan_enable_name_pattern, scan_in_name_pattern, scan_out_name_pattern);
+}
 
-void insert_dft()
+void write_scan_chains(const char* filename_p)
 {
-  getDft()->insertDft();
+  std::string filename(filename_p);
+  getDft()->writeScanChains(filename);
 }
 
 void set_dft_config_max_length(int max_length)

src/dft/src/dft.tcl

@@ -29,7 +29,7 @@
 # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 # POSSIBILITY OF SUCH DAMAGE.
 
-sta::define_cmd_args "preview_dft" { [-verbose]}
+sta::define_cmd_args "preview_dft" {[-verbose]}
 
 proc preview_dft { args } {
   sta::parse_key_args "preview_dft" args \
@@ -58,15 +58,46 @@ proc scan_replace { args } {
   dft::scan_replace
 }
 
-sta::define_cmd_args "insert_dft" { }
+sta::define_cmd_args "write_scan_chains" {[json_file_out]}
+proc write_scan_chains { args } {
+  sta::parse_key_args "write_scan_chains" args \
+    keys {} flags {}
+
+  if { [ord::get_db_block] == "NULL" } {
+    utl::error DFT 15 "No design block found."
+  }
+
+  dft::write_scan_chains [lindex $args 0]
+}
+
+sta::define_cmd_args "insert_dft" {
+  [-per_chain_enable]
+  [-scan_enable_name_pattern scan_enable_name_pattern]
+  [-scan_in_name_pattern scan_in_name_pattern]
+  [-scan_out_name_pattern scan_out_name_pattern]
+}
 proc insert_dft { args } {
   sta::parse_key_args "insert_dft" args \
-    keys {} flags {}
+    keys {-scan_enable_name_pattern -scan_in_name_pattern -scan_out_name_pattern} \
+    flags {-per_chain_enable}
 
   if { [ord::get_db_block] == "NULL" } {
     utl::error DFT 9 "No design block found."
   }
-  dft::insert_dft
+
+  foreach {flag default} {
+    -scan_enable_name_pattern "scan_enable_{}"
+    -scan_in_name_pattern "scan_in_{}"
+    -scan_out_name_pattern "scan_out_{}"
+  } {
+    if { ![info exists keys($flag)] } {
+      set keys($flag) $default
+    }
+  }
+  dft::insert_dft [info exists flags(-per_chain_enable)] \
+    $keys(-scan_enable_name_pattern) \
+    $keys(-scan_in_name_pattern) \
+    $keys(-scan_out_name_pattern)
 }
 
 sta::define_cmd_args "set_dft_config" { [-max_length max_length] \

src/dft/src/replace/ScanReplace.cpp

@@ -45,19 +45,6 @@
 namespace dft {
 
 namespace {
-
-// Checks if the given LibertyCell is really a Scan Cell with a Scan In and a
-// Scan Enable
-bool IsScanCell(const sta::LibertyCell* libertyCell)
-{
-  const sta::TestCell* test_cell = libertyCell->testCell();
-  if (test_cell) {
-    return getLibertyScanIn(test_cell) != nullptr
-           && getLibertyScanEnable(test_cell) != nullptr;
-  }
-  return false;
-}
-
 // Checks the ports
 sta::LibertyPort* FindEquivalentPortInScanCell(
     const sta::LibertyPort* non_scan_cell_port,
@@ -309,7 +296,7 @@ void ScanReplace::collectScanCellAvailable()
         continue;
       }
 
-      if (IsScanCell(liberty_cell)) {
+      if (utils::IsScanCell(liberty_cell)) {
         available_scan_lib_cells_.insert(liberty_cell);
       } else {
         non_scan_cells.push_back(liberty_cell);