fix(esp_system): fix RTC reserved area alignment in the linker script

Make sure the size of the RTC reserved area complies with the alignment requirement.

Closes #13082

Author: o-marshmallow

components/bootloader_support/src/bootloader_common_loader.c

@@ -28,6 +28,7 @@
 
 #define ESP_PARTITION_HASH_LEN 32 /* SHA-256 digest length */
 #define IS_FIELD_SET(rev_full) (((rev_full) != 65535) && ((rev_full) != 0))
+#define ALIGN_UP(num, align) (((num) + ((align) - 1)) & ~((align) - 1))
 
 static const char* TAG = "boot_comm";
 
@@ -264,7 +265,10 @@ rtc_retain_mem_t* bootloader_common_get_rtc_retain_mem(void)
 #if ESP_ROM_HAS_LP_ROM
     #define RTC_RETAIN_MEM_ADDR (SOC_RTC_DRAM_LOW)
 #else
-    #define RTC_RETAIN_MEM_ADDR (SOC_RTC_DRAM_HIGH - sizeof(rtc_retain_mem_t))
+    /* Since the structure containing the retain_mem_t is aligned on 8 by the linker, make sure we align this
+     * structure size here too */
+    #define RETAIN_MEM_SIZE     ALIGN_UP(sizeof(rtc_retain_mem_t), 8)
+    #define RTC_RETAIN_MEM_ADDR (SOC_RTC_DRAM_HIGH - RETAIN_MEM_SIZE)
 #endif //ESP_ROM_HAS_LP_ROM
     static rtc_retain_mem_t *const s_bootloader_retain_mem = (rtc_retain_mem_t *)RTC_RETAIN_MEM_ADDR;
     return s_bootloader_retain_mem;

components/esp_system/ld/ld.common

@@ -6,6 +6,8 @@
 
 #include "sdkconfig.h"
 
+#define ALIGN_UP(SIZE, AL)   (((SIZE) + (AL - 1)) & ~(AL - 1))
+
 /* CPU instruction prefetch padding size for flash mmap scenario */
 #define _esp_flash_mmap_prefetch_pad_size 16
 
@@ -45,10 +47,14 @@
 
 #if CONFIG_SOC_RTC_MEM_SUPPORTED
     #if CONFIG_BOOTLOADER_RESERVE_RTC_MEM
+        /**
+         * The ESP_BOOTLOADER_RESERVE_RTC size must have the same alignment of RTC_TIMER_RESERVE_RTC, else
+         * the segment will overflow at link time because not enough bytes are allocated for the RTC segment.
+         */
         #ifdef CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC
-            #define ESP_BOOTLOADER_RESERVE_RTC (CONFIG_BOOTLOADER_RESERVE_RTC_SIZE + CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC_SIZE)
+            #define ESP_BOOTLOADER_RESERVE_RTC ALIGN_UP(CONFIG_BOOTLOADER_RESERVE_RTC_SIZE + CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC_SIZE, 8)
         #else
-            #define ESP_BOOTLOADER_RESERVE_RTC (CONFIG_BOOTLOADER_RESERVE_RTC_SIZE)
+            #define ESP_BOOTLOADER_RESERVE_RTC ALIGN_UP(CONFIG_BOOTLOADER_RESERVE_RTC_SIZE, 8)
         #endif // not CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC
     #else
         #define ESP_BOOTLOADER_RESERVE_RTC 0