Xtensa ISS PAL layer for logging/timing. (#7311)

Summary:

Overrides for `et_pal*` weak symbols for logging/timing with xtensa ISS.

Reviewed By: zonglinpeng

Differential Revision: D67128599

Author: hsharma35

backends/cadence/runtime/TARGETS

@@ -1,3 +1,4 @@
+load(":targets.bzl", "define_common_targets")
 load("@fbcode_macros//build_defs:python_library.bzl", "python_library")
 
 oncall("odai_jarvis")
@@ -22,3 +23,5 @@ python_library(
         "//executorch/exir:lib",
     ],
 )
+
+define_common_targets()

backends/cadence/runtime/et_pal.cpp

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#if defined(XTENSA)
+
+#include <stdio.h>
+#include <sys/times.h>
+
+#include <xtensa/sim.h>
+
+#include <executorch/runtime/platform/platform.h>
+
+#define ET_LOG_OUTPUT_FILE stdout
+
+void et_pal_emit_log_message(
+    et_timestamp_t timestamp,
+    et_pal_log_level_t level,
+    const char* filename,
+    ET_UNUSED const char* function,
+    size_t line,
+    const char* message,
+    ET_UNUSED size_t length) {
+  // Not all platforms have ticks == nanoseconds, but this one does.
+  timestamp /= 1000; // To microseconds
+  int us = timestamp % 1000000;
+  timestamp /= 1000000; // To seconds
+  int sec = timestamp % 60;
+  timestamp /= 60; // To minutes
+  int min = timestamp % 60;
+  timestamp /= 60; // To hours
+  int hour = timestamp;
+
+  fprintf(
+      ET_LOG_OUTPUT_FILE,
+      "%c %02d:%02d:%02d.%06d executorch:%s:%d] %s\n",
+      static_cast<char>(level),
+      hour,
+      min,
+      sec,
+      us,
+      filename,
+      static_cast<int>(line),
+      message);
+  fflush(ET_LOG_OUTPUT_FILE);
+}
+
+et_timestamp_t et_pal_current_ticks(void) {
+  struct tms curr_time;
+  times(&curr_time);
+  return curr_time.tms_utime;
+}
+
+void et_pal_init(void) {
+  xt_iss_client_command("all", "enable");
+}
+
+#else
+
+#include <time.h>
+
+#include <cstdio>
+#include <cstdlib>
+
+#include <executorch/runtime/platform/platform.h>
+
+#define ET_LOG_OUTPUT_FILE stderr
+
+#define NSEC_PER_USEC 1000UL
+#define USEC_IN_SEC 1000000UL
+#define NSEC_IN_USEC 1000UL
+#define NSEC_IN_SEC (NSEC_IN_USEC * USEC_IN_SEC)
+
+et_timestamp_t et_pal_current_ticks(void) {
+  struct timespec ts;
+  auto ret = clock_gettime(CLOCK_REALTIME, &ts);
+  if (ret != 0) {
+    fprintf(ET_LOG_OUTPUT_FILE, "Could not get time\n");
+    fflush(ET_LOG_OUTPUT_FILE);
+    std::abort();
+  }
+
+  return ((ts.tv_sec * NSEC_IN_SEC) + (ts.tv_nsec));
+}
+
+#endif

backends/cadence/runtime/targets.bzl

@@ -0,0 +1,15 @@
+load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
+
+def define_common_targets():
+    runtime.cxx_library(
+        name = "et_pal",
+        srcs = ["et_pal.cpp"],
+        link_whole = True,
+        visibility = [
+            "//executorch/backends/cadence/...",
+            "@EXECUTORCH_CLIENTS"
+        ],
+        exported_deps = [
+            "//executorch/runtime/platform:platform",
+        ],
+    )