Generalize DTC compilation to support both DTS/B

Author: abejgonzalez

riscv/dts.cc

@@ -99,86 +99,91 @@ std::string make_dts(size_t insns_per_rtc_tick, size_t cpu_hz,
   return s.str();
 }
 
-std::string dts_compile(const std::string& dts)
+std::string dtc_compile(const std::string& dtc_input, const std::string& input_type, const std::string& output_type)
 {
-  // Convert the DTS to DTB
-  int dts_pipe[2];
-  pid_t dts_pid;
+  if (input_type == output_type)
+    std::cerr << "Must have differing {in,out}put types for running " DTC << std::endl;
+
+  if (!((input_type == "dts" && output_type == "dtb") || (input_type == "dtb" && output_type == "dts")))
+    std::cerr << "Invalid {in,out}put types for running " DTC ": Must convert from 'dts' to 'dtb' (or vice versa)" << std::endl;
+
+  int dtc_input_pipe[2];
+  pid_t dtc_input_pid;
 
   fflush(NULL); // flush stdout/stderr before forking
-  if (pipe(dts_pipe) != 0 || (dts_pid = fork()) < 0) {
-    std::cerr << "Failed to fork dts child: " << strerror(errno) << std::endl;
+  if (pipe(dtc_input_pipe) != 0 || (dtc_input_pid = fork()) < 0) {
+    std::cerr << "Failed to fork dtc_input child: " << strerror(errno) << std::endl;
     exit(1);
   }
 
-  // Child process to output dts
-  if (dts_pid == 0) {
-    close(dts_pipe[0]);
-    int step, len = dts.length();
-    const char *buf = dts.c_str();
+  // Child process to output dtc_input
+  if (dtc_input_pid == 0) {
+    close(dtc_input_pipe[0]);
+    int step, len = dtc_input.length();
+    const char *buf = dtc_input.c_str();
     for (int done = 0; done < len; done += step) {
-      step = write(dts_pipe[1], buf+done, len-done);
+      step = write(dtc_input_pipe[1], buf+done, len-done);
       if (step == -1) {
-        std::cerr << "Failed to write dts: " << strerror(errno) << std::endl;
+        std::cerr << "Failed to write dtc_input: " << strerror(errno) << std::endl;
         exit(1);
       }
     }
-    close(dts_pipe[1]);
+    close(dtc_input_pipe[1]);
     exit(0);
   }
 
-  pid_t dtb_pid;
-  int dtb_pipe[2];
-  if (pipe(dtb_pipe) != 0 || (dtb_pid = fork()) < 0) {
-    std::cerr << "Failed to fork dtb child: " << strerror(errno) << std::endl;
+  pid_t dtc_output_pid;
+  int dtc_output_pipe[2];
+  if (pipe(dtc_output_pipe) != 0 || (dtc_output_pid = fork()) < 0) {
+    std::cerr << "Failed to fork dtc_output child: " << strerror(errno) << std::endl;
     exit(1);
   }
 
-  // Child process to output dtb
-  if (dtb_pid == 0) {
-    dup2(dts_pipe[0], 0);
-    dup2(dtb_pipe[1], 1);
-    close(dts_pipe[0]);
-    close(dts_pipe[1]);
-    close(dtb_pipe[0]);
-    close(dtb_pipe[1]);
-    execlp(DTC, DTC, "-O", "dtb", (char *)0);
+  // Child process to output dtc_output
+  if (dtc_output_pid == 0) {
+    dup2(dtc_input_pipe[0], 0);
+    dup2(dtc_output_pipe[1], 1);
+    close(dtc_input_pipe[0]);
+    close(dtc_input_pipe[1]);
+    close(dtc_output_pipe[0]);
+    close(dtc_output_pipe[1]);
+    execlp(DTC, DTC, "-O", output_type.c_str(), "-I", input_type.c_str(), (char *)0);
     std::cerr << "Failed to run " DTC ": " << strerror(errno) << std::endl;
     exit(1);
   }
 
-  close(dts_pipe[1]);
-  close(dts_pipe[0]);
-  close(dtb_pipe[1]);
+  close(dtc_input_pipe[1]);
+  close(dtc_input_pipe[0]);
+  close(dtc_output_pipe[1]);
 
-  // Read-out dtb
-  std::stringstream dtb;
+  // Read-out dtc_output
+  std::stringstream dtc_output;
 
   int got;
   char buf[4096];
-  while ((got = read(dtb_pipe[0], buf, sizeof(buf))) > 0) {
-    dtb.write(buf, got);
+  while ((got = read(dtc_output_pipe[0], buf, sizeof(buf))) > 0) {
+    dtc_output.write(buf, got);
   }
   if (got == -1) {
-    std::cerr << "Failed to read dtb: " << strerror(errno) << std::endl;
+    std::cerr << "Failed to read dtc_output: " << strerror(errno) << std::endl;
     exit(1);
   }
-  close(dtb_pipe[0]);
+  close(dtc_output_pipe[0]);
 
   // Reap children
   int status;
-  waitpid(dts_pid, &status, 0);
+  waitpid(dtc_input_pid, &status, 0);
   if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
-    std::cerr << "Child dts process failed" << std::endl;
+    std::cerr << "Child dtc_input process failed" << std::endl;
     exit(1);
   }
-  waitpid(dtb_pid, &status, 0);
+  waitpid(dtc_output_pid, &status, 0);
   if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
-    std::cerr << "Child dtb process failed" << std::endl;
+    std::cerr << "Child dtc_output process failed" << std::endl;
     exit(1);
   }
 
-  return dtb.str();
+  return dtc_output.str();
 }
 
 int fdt_get_node_addr_size(const void *fdt, int node, reg_t *addr,

riscv/dts.h

@@ -11,7 +11,7 @@ std::string make_dts(size_t insns_per_rtc_tick, size_t cpu_hz,
                      std::vector<std::pair<reg_t, abstract_mem_t*>> mems,
                      std::string device_nodes);
 
-std::string dts_compile(const std::string& dts);
+std::string dtc_compile(const std::string& dtc_input, const std::string& input_type, const std::string& output_type);
 
 int fdt_get_node_addr_size(const void *fdt, int node, reg_t *addr,
                            unsigned long *size, const char *field);

riscv/sim.cc

@@ -133,6 +133,7 @@ sim_t::sim_t(const cfg_t *cfg, bool halted,
     std::stringstream strstream;
     strstream << fin.rdbuf();
     dtb = strstream.str();
+    dts = dtc_compile(dtb, "dtb", "dts");
   } else {
     std::pair<reg_t, reg_t> initrd_bounds = cfg->initrd_bounds;
     std::string device_nodes;
@@ -142,7 +143,7 @@ sim_t::sim_t(const cfg_t *cfg, bool halted,
       device_nodes.append(factory->generate_dts(this, sargs));
     }
     dts = make_dts(INSNS_PER_RTC_TICK, CPU_HZ, cfg, mems, device_nodes);
-    dtb = dts_compile(dts);
+    dtb = dtc_compile(dts, "dts", "dtb");
   }
 
   int fdt_code = fdt_check_header(dtb.c_str());