env: ti: boot: Handle reboot reason from BCB

In case of Android boot, reboot reason can be written into BCB (usually
it's an area in 'misc' partition). U-Boot then can obtain that reboot
reason from BCB and handle it accordingly to achieve correct Android
boot flow, like it was suggested in [1]:
  - if it's empty: perform normal Android boot from eMMC
  - if it contains "bootonce-bootloader": get into fastboot mode
  - if it contains "boot-recovery": perform recovery boot

The latter is not implemented yet, as it depends on some features that
are not implemented on TI platforms yet (in AOSP and in U-Boot).

[1] https://marc.info/?l=u-boot&m=152508418909737&w=2

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>

diff --git a/include/environment/ti/boot.h b/include/environment/ti/boot.h
index e55a4aec57c5f3f96f7bf9b3f8cca2a95a6c1f91..684a744f312137fc87b07b711c7ef48996724419 100644 (file)
--- a/include/environment/ti/boot.h
+++ b/include/environment/ti/boot.h
@@ -98,6 +98,10 @@
 #define AB_SELECT ""
 #endif
 
+#define FASTBOOT_CMD \
+       "echo Booting into fastboot ...; " \
+       "fastboot " __stringify(CONFIG_FASTBOOT_USB_DEV) "; "
+
 #define DEFAULT_COMMON_BOOT_TI_ARGS \
        "console=" CONSOLEDEV ",115200n8\0" \
        "fdtfile=undefined\0" \
@@ -117,6 +121,28 @@
                "setenv mmcroot /dev/mmcblk0p2 rw; " \
                "run mmcboot;\0" \
        "emmc_android_boot=" \
+               "if bcb load " __stringify(CONFIG_FASTBOOT_FLASH_MMC_DEV) " " \
+               CONTROL_PARTITION "; then " \
+                       "if bcb test command = bootonce-bootloader; then " \
+                               "echo BCB: Bootloader boot...; " \
+                               "bcb clear command; bcb store; " \
+                               FASTBOOT_CMD \
+                       "elif bcb test command = boot-recovery; then " \
+                               "echo BCB: Recovery boot...; " \
+                               "echo Warning: recovery is not implemented; " \
+                               "echo Performing normal boot for now...; " \
+                               "bcb clear command; bcb store; " \
+                               "run emmc_android_normal_boot; " \
+                       "else " \
+                               "echo BCB: Normal boot requested...; " \
+                               "run emmc_android_normal_boot; " \
+                       "fi; " \
+               "else " \
+                       "echo Warning: BCB is corrupted or does not exist; " \
+                       "echo Performing normal boot...; " \
+                       "run emmc_android_normal_boot; " \
+               "fi;\0" \
+       "emmc_android_normal_boot=" \
                "echo Trying to boot Android from eMMC ...; " \
                "run update_to_fit; " \
                "setenv eval_bootargs setenv bootargs $bootargs; " \
@@ -176,8 +202,7 @@
        "if test ${dofastboot} -eq 1; then " \
                "echo Boot fastboot requested, resetting dofastboot ...;" \
                "setenv dofastboot 0; saveenv;" \
-               "echo Booting into fastboot ...; " \
-               "fastboot " __stringify(CONFIG_FASTBOOT_USB_DEV) "; " \
+               FASTBOOT_CMD \
        "fi;" \
        "if test ${boot_fit} -eq 1; then "      \
                "run update_to_fit;"    \