Fix efr32 build using provision flash storage

Author: jmartinez-silabs

examples/platform/silabs/provision/BUILD.gn

@@ -1,4 +1,4 @@
-# Copyright (c) 2020 Project CHIP Authors
+# Copyright (c) 2024 Project CHIP Authors
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -22,10 +22,6 @@ if (wifi_soc) {
   import("${efr32_sdk_build_root}/efr32_sdk.gni")
 }
 
-declare_args() {
-  use_flash_storage = wifi_soc
-}
-
 source_set("provision-storage") {
   sources = [ "ProvisionStorageCustom.cpp" ]
 

src/platform/silabs/efr32/efr32-chip-mbedtls-config.h

@@ -87,6 +87,12 @@
 #define PSA_WANT_ALG_SOME_PAKE
 #endif // SL_USE_COAP_CONFIG
 
+#if SL_PROVISION_FLASH
+#define MBEDTLS_SHA256_C
+#define MBEDTLS_HMAC_DRBG_C
+#define MBEDTLS_ECDSA_DETERMINISTIC
+#endif
+
 #define MBEDTLS_PLATFORM_SNPRINTF_MACRO snprintf
 
 #define MBEDTLS_AES_ROM_TABLES

third_party/silabs/SiWx917_sdk.gni

@@ -38,6 +38,9 @@ declare_args() {
 
   # enable 917 SoC M4 sleep wakeup
   si917_m4_sleep_enabled = false
+
+  # Factory Provision storage
+  use_flash_storage = true
 }
 
 # Defines an siwx917 SDK build target.

third_party/silabs/efr32_sdk.gni

@@ -82,6 +82,9 @@ declare_args() {
   chip_enable_multi_ota_requestor = false
   chip_enable_multi_ota_encryption = false
   chip_enable_ota_custom_tlv_testing = false
+
+  # Factory Provision storage
+  use_flash_storage = false
 }
 
 examples_plat_dir = "${chip_root}/examples/platform/silabs/efr32"
@@ -469,6 +472,12 @@ template("efr32_sdk") {
       defines += [ "SL_USE_COAP_CONFIG=0" ]
     }
 
+    if (use_flash_storage) {
+      defines += [ "SL_PROVISION_FLASH=1" ]
+    } else {
+      defines += [ "SL_PROVISION_FLASH=0" ]
+    }
+
     if (chip_enable_ble_rs911x) {
       defines += [
         "RSI_BLE_ENABLE=1",