boot: zephyr: add config for swap without scratch

Add Zephyr option to enable building a bootloader that uses an alternative swap algorithm, that first moves up all sectors in slot1 and then directly swaps between slot0 and slot1. Signed-off-by: Fabio Utzig <utzig@apache.org>
mcu-tools · Nov 28, 2019 · fbc4a97 · fbc4a97
1 parent 2973b85
commit fbc4a97
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Showing 7 changed files with 27 additions and 2 deletions.
diff --git a/boot/zephyr/CMakeLists.txt b/boot/zephyr/CMakeLists.txt
@@ -103,6 +103,8 @@ endif()
 zephyr_library_include_directories(${BOOT_DIR}/bootutil/include)
 zephyr_library_sources(
   ${BOOT_DIR}/bootutil/src/loader.c
+  ${BOOT_DIR}/bootutil/src/swap_scratch.c
+  ${BOOT_DIR}/bootutil/src/swap_move.c
   ${BOOT_DIR}/bootutil/src/bootutil_misc.c
   ${BOOT_DIR}/bootutil/src/image_validate.c
   ${BOOT_DIR}/bootutil/src/encrypted.c

diff --git a/boot/zephyr/Kconfig b/boot/zephyr/Kconfig
@@ -126,6 +126,19 @@ config BOOT_UPGRADE_ONLY
 	  of swapping them. This prevents the fallback recovery, but
 	  uses a much simpler code path.
 
+config BOOT_SWAP_USING_MOVE
+	bool "Swap mode that can run without a scratch partition"
+	default n
+	help
+	  If y, the swap upgrade is done in two steps, where first every
+	  sector of the secondary slot is moved up one sector, then for
+	  each sector X in the primary slot, it is moved to index X in
+	  the secondary slot, then the sector at X+1 in the secondary is
+	  moved to index X in the primary.
+	  This allows a swap upgrade without using a scratch partition,
+	  but is currently limited to all sectors in both slots being of
+	  the same size.
+
 config BOOT_BOOTSTRAP
 	bool "Bootstrap erased the primary slot from the secondary slot"
 	default n

diff --git a/boot/zephyr/flash_map_extended.c b/boot/zephyr/flash_map_extended.c
@@ -58,7 +58,9 @@ int flash_area_id_from_multi_image_slot(int image_index, int slot)
     switch (slot) {
     case 0: return FLASH_AREA_IMAGE_PRIMARY(image_index);
     case 1: return FLASH_AREA_IMAGE_SECONDARY(image_index);
+#if !defined(CONFIG_BOOT_SWAP_USING_MOVE)
     case 2: return FLASH_AREA_IMAGE_SCRATCH;
+#endif
     }
 
     return -EINVAL; /* flash_area_open will fail on that */

diff --git a/boot/zephyr/include/mcuboot_config/mcuboot_config.h b/boot/zephyr/include/mcuboot_config/mcuboot_config.h
@@ -53,6 +53,10 @@
 #define MCUBOOT_OVERWRITE_ONLY_FAST
 #endif
 
+#ifdef CONFIG_BOOT_SWAP_USING_MOVE
+#define MCUBOOT_SWAP_USING_MOVE 1
+#endif
+
 #ifdef CONFIG_LOG
 #define MCUBOOT_HAVE_LOGGING 1
 #endif

diff --git a/boot/zephyr/include/sysflash/sysflash.h b/boot/zephyr/include/sysflash/sysflash.h
@@ -37,6 +37,8 @@
 #error "Image slot and flash area mapping is not defined"
 #endif
 
+#if !defined(CONFIG_BOOT_SWAP_USING_MOVE)
 #define FLASH_AREA_IMAGE_SCRATCH    DT_FLASH_AREA_IMAGE_SCRATCH_ID
+#endif
 
 #endif /* __SYSFLASH_H__ */
diff --git a/boot/zephyr/include/target.h b/boot/zephyr/include/target.h
@@ -42,8 +42,8 @@
     !defined(FLASH_AREA_IMAGE_0_SIZE) || \
     !defined(FLASH_AREA_IMAGE_1_OFFSET) || \
     !defined(FLASH_AREA_IMAGE_1_SIZE) || \
-    !defined(FLASH_AREA_IMAGE_SCRATCH_OFFSET) || \
-    !defined(FLASH_AREA_IMAGE_SCRATCH_SIZE)
+    (!defined(CONFIG_BOOT_SWAP_USING_MOVE) && !defined(FLASH_AREA_IMAGE_SCRATCH_OFFSET)) || \
+    (!defined(CONFIG_BOOT_SWAP_USING_MOVE) && !defined(FLASH_AREA_IMAGE_SCRATCH_SIZE))
 #error "Target support is incomplete; cannot build mcuboot."
 #endif
 

diff --git a/boot/zephyr/prj.conf b/boot/zephyr/prj.conf
@@ -9,6 +9,8 @@ CONFIG_MBEDTLS_CFG_FILE="mcuboot-mbedtls-cfg.h"
 CONFIG_BOOT_ENCRYPT_RSA=n
 CONFIG_BOOT_ENCRYPT_EC256=n
 
+CONFIG_BOOT_UPGRADE_ONLY=n
+CONFIG_BOOT_SWAP_USING_MOVE=n
 CONFIG_BOOT_BOOTSTRAP=n
 
 ### Default to RSA