esp_system: create ld template to abstract few common settings

PMS aware chips require prefetch padding size for instruction fetch, or
some memory alignment considerations. These settings are now exposed
through kconfig options (hidden) and used through common ld template.
This shall help to add and manage future chips support easily for
these considerations.

Closes IDF-3624

components/esp_system/ld/esp32s2/memory.ld.in

@@ -13,6 +13,7 @@
    Restrict to simple macros with numeric values, and/or #if/#endif blocks.
 */
 #include "sdkconfig.h"
+#include "ld.common"
 
 #ifdef CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC
 #define ESP_BOOTLOADER_RESERVE_RTC (CONFIG_BOOTLOADER_RESERVE_RTC_SIZE + CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC_SIZE)

components/esp_system/ld/esp32s2/sections.ld.in

@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 /*  Default entry point:  */
 ENTRY(call_start_cpu0);
 
@@ -177,7 +183,7 @@ SECTIONS
     _coredump_iram_end = 0;
 
     /* align + add 16B for CPU dummy speculative instr. fetch */
-    . = ALIGN(4) + 16;
+    . = ALIGN(_esp_memprot_align_size) + _esp_memprot_prefetch_pad_size;
     /* iram_end_test section exists for use by memprot unit tests only */
     *(.iram_end_test)
     _iram_text_end = ABSOLUTE(.);
@@ -363,7 +369,7 @@ SECTIONS
       * safe access to up to 16 bytes after the last real instruction, add
       * dummy bytes to ensure this
       */
-    . += 16;
+    . += _esp_flash_mmap_prefetch_pad_size;
 
     _text_end = ABSOLUTE(.);
     _instruction_reserved_end = ABSOLUTE(.);