Add type annotations to _require_rmt_iram

The esp32 to_code runs at PLATFORM priority (1000) before component
to_code at COMPONENT priority (0), so the flag was set too late.
Move to config validation to ensure it is set before esp32 processes
sdkconfig options.

esphome/components/esp32/__init__.py

@@ -1058,6 +1058,7 @@ CONF_DISABLE_MBEDTLS_PEER_CERT = "disable_mbedtls_peer_cert"
 CONF_DISABLE_MBEDTLS_PKCS7 = "disable_mbedtls_pkcs7"
 CONF_DISABLE_REGI2C_IN_IRAM = "disable_regi2c_in_iram"
 CONF_DISABLE_FATFS = "disable_fatfs"
+CONF_RMT_RECV_IN_IRAM = "rmt_recv_in_iram"
 
 # VFS requirement tracking
 # Components that need VFS features can call require_vfs_*() functions
@@ -1071,6 +1072,7 @@ KEY_MBEDTLS_PEER_CERT_REQUIRED = "mbedtls_peer_cert_required"
 KEY_MBEDTLS_PKCS7_REQUIRED = "mbedtls_pkcs7_required"
 KEY_FATFS_REQUIRED = "fatfs_required"
 KEY_MBEDTLS_SHA512_REQUIRED = "mbedtls_sha512_required"
+KEY_RMT_RECV_IRAM_REQUIRED = "rmt_recv_iram_required"
 
 
 def require_vfs_select() -> None:
@@ -1168,6 +1170,17 @@ def require_fatfs() -> None:
     CORE.data[KEY_ESP32][KEY_FATFS_REQUIRED] = True
 
 
+def require_rmt_recv_iram() -> None:
+    """Mark that RMT receive IRAM safety is required by a component.
+
+    Call this from components that use the RMT receive driver. When flash cache is
+    disabled (e.g., during NVS writes by WiFi, BLE, Zigbee, or power management),
+    the RMT receive function must be in IRAM to avoid crashes.
+    This sets CONFIG_RMT_RECV_FUNC_IN_IRAM.
+    """
+    CORE.data[KEY_ESP32][KEY_RMT_RECV_IRAM_REQUIRED] = True
+
+
 def _parse_idf_component(value: str) -> ConfigType:
     """Parse IDF component shorthand syntax like 'owner/component^version'"""
     # Match operator followed by version-like string (digit or *)
@@ -1268,6 +1281,7 @@ FRAMEWORK_SCHEMA = cv.Schema(
                 cv.Optional(CONF_DISABLE_MBEDTLS_PEER_CERT, default=True): cv.boolean,
                 cv.Optional(CONF_DISABLE_MBEDTLS_PKCS7, default=True): cv.boolean,
                 cv.Optional(CONF_DISABLE_REGI2C_IN_IRAM, default=True): cv.boolean,
+                cv.Optional(CONF_RMT_RECV_IN_IRAM, default=False): cv.boolean,
                 cv.Optional(CONF_DISABLE_FATFS, default=True): cv.boolean,
             }
         ),
@@ -2068,6 +2082,16 @@ async def to_code(config):
     if advanced[CONF_DISABLE_REGI2C_IN_IRAM]:
         add_idf_sdkconfig_option("CONFIG_ESP_REGI2C_CTRL_FUNC_IN_IRAM", False)
 
+    # Place RMT receive functions in IRAM for cache safety
+    # When flash cache is disabled (during NVS writes by WiFi, BLE, Zigbee, Thread,
+    # power management, etc.), RMT receive will crash if these functions are in flash.
+    # Components using RMT receive call require_rmt_recv_iram() to force this.
+    if (
+        CORE.data[KEY_ESP32].get(KEY_RMT_RECV_IRAM_REQUIRED, False)
+        or advanced[CONF_RMT_RECV_IN_IRAM]
+    ):
+        add_idf_sdkconfig_option("CONFIG_RMT_RECV_FUNC_IN_IRAM", True)
+
     # Disable FATFS support
     # Components that need FATFS (SD card, etc.) can call require_fatfs()
     if CORE.data[KEY_ESP32].get(KEY_FATFS_REQUIRED, False):

esphome/components/remote_receiver/__init__.py

@@ -21,6 +21,7 @@ from esphome.const import (
     PlatformFramework,
 )
 from esphome.core import CORE, TimePeriod
+from esphome.types import ConfigType
 
 CONF_FILTER_SYMBOLS = "filter_symbols"
 CONF_RECEIVE_SYMBOLS = "receive_symbols"
@@ -101,6 +102,13 @@ def validate_tolerance(value):
     )
 
 
+def _require_rmt_iram(config: ConfigType) -> ConfigType:
+    """Register RMT receive IRAM requirement during config validation."""
+    if CORE.is_esp32 and esp32.get_esp32_variant() not in esp32_rmt.VARIANTS_NO_RMT:
+        esp32.require_rmt_recv_iram()
+    return config
+
+
 MULTI_CONF = True
 CONFIG_SCHEMA = remote_base.validate_triggers(
     cv.Schema(
@@ -193,6 +201,7 @@ CONFIG_SCHEMA = remote_base.validate_triggers(
         )
     )
     .add_extra(validate_config)
+    .add_extra(_require_rmt_iram)
 )