[core] Move platform helper implementations into their own file (#9361)

esphome/components/esp8266/helpers.cpp

@@ -0,0 +1,31 @@
+#include "esphome/core/helpers.h"
+
+#ifdef USE_ESP8266
+
+#include <osapi.h>
+#include <user_interface.h>
+// for xt_rsil()/xt_wsr_ps()
+#include <Arduino.h>
+
+namespace esphome {
+
+uint32_t random_uint32() { return os_random(); }
+bool random_bytes(uint8_t *data, size_t len) { return os_get_random(data, len) == 0; }
+
+// ESP8266 doesn't have mutexes, but that shouldn't be an issue as it's single-core and non-preemptive OS.
+Mutex::Mutex() {}
+Mutex::~Mutex() {}
+void Mutex::lock() {}
+bool Mutex::try_lock() { return true; }
+void Mutex::unlock() {}
+
+IRAM_ATTR InterruptLock::InterruptLock() { state_ = xt_rsil(15); }
+IRAM_ATTR InterruptLock::~InterruptLock() { xt_wsr_ps(state_); }
+
+void get_mac_address_raw(uint8_t *mac) {  // NOLINT(readability-non-const-parameter)
+  wifi_get_macaddr(STATION_IF, mac);
+}
+
+}  // namespace esphome
+
+#endif  // USE_ESP8266