diff --git a/components/esp8266/source/chip_boot.c b/components/esp8266/source/chip_boot.c
index 24a53bbb..b2d5b7ca 100644
--- a/components/esp8266/source/chip_boot.c
+++ b/components/esp8266/source/chip_boot.c
@@ -86,7 +86,7 @@ void chip_boot(size_t start_addr, size_t map)
 
     ret = spi_flash_read(start_addr, &fhdr, sizeof(flash_hdr_t));
     if (ret) {
-        ESP_LOGE(TAG, "SPI flash read result %d\n", ret);
+        ESP_EARLY_LOGE(TAG, "SPI flash read result %d\n", ret);
     }
 
     if (3 > fhdr.spi_speed)
@@ -100,7 +100,7 @@ void chip_boot(size_t start_addr, size_t map)
         flash_size = flash_map_table[fhdr.spi_size_map];
     } else {
         flash_size = 0; 
-        ESP_LOGE(TAG, "SPI size error is %d\n", fhdr.spi_size_map);
+        ESP_EARLY_LOGE(TAG, "SPI size error is %d\n", fhdr.spi_size_map);
     }
     sect_size = 4 * 1024;
 
@@ -117,7 +117,7 @@ void chip_boot(size_t start_addr, size_t map)
 
     ret = esp_get_boot_param(flash_size, sect_size, &bhdr, sizeof(boot_hdr_t));
     if (ret) {
-        ESP_LOGE(TAG, "Get boot parameters %d\n", ret);
+        ESP_EARLY_LOGE(TAG, "Get boot parameters %d\n", ret);
     }
 
     cache_init(map, 0, 0);
diff --git a/components/esp8266/source/startup.c b/components/esp8266/source/startup.c
index bb40565d..a7b81d8c 100644
--- a/components/esp8266/source/startup.c
+++ b/components/esp8266/source/startup.c
@@ -87,19 +87,25 @@ void call_user_start(size_t start_addr, size_t map)
             *dest++ = *src++;
     }
 
+    /* 
+     * When finish copying IRAM program, the exception vect must be initialized.
+     * And then user can load/store data which is not aligned by 4-byte.
+     */
+    __asm__ __volatile__(
+        "movi       a2, 0x40100000\n"
+        "wsr        a2, vecbase\n");
+
+    chip_boot(start_addr, map);
+
     /* clear bss data */
     for (p = &_bss_start; p < &_bss_end; p++)
         *p = 0;
 
-    chip_boot(start_addr, map);
-
     __asm__ __volatile__(
         "rsil       a2, 2\n"
         "movi       a1, _chip_interrupt_tmp\n"
         "movi       a2, 0xffffff00\n"
-        "and        a1, a1, a2\n"
-        "movi       a2, 0x40100000\n"
-        "wsr        a2, vecbase\n");
+        "and        a1, a1, a2\n");
 
     wifi_os_init();
 
diff --git a/components/spi_flash/src/spi_flash.c b/components/spi_flash/src/spi_flash.c
index 275fa908..340c7f24 100644
--- a/components/spi_flash/src/spi_flash.c
+++ b/components/spi_flash/src/spi_flash.c
@@ -25,7 +25,8 @@
 #include "esp8266/pin_mux_register.h"
 #include "driver/spi_register.h"
 
-#define spi_debug(fmt, ...)                     ESP_LOGD(TAG, fmt, ##__VA_ARGS__)
+/* Todo: Refactor SPI debug */
+#define spi_debug(fmt, ...)                     //ESP_LOGD(TAG, fmt, ##__VA_ARGS__)
 
 #define SPI_EXT2(i)                             (REG_SPI_BASE(i) + 0xF8)
 #define SPI_EXT3(i)                             (REG_SPI_BASE(i) + 0xFC)