Selecting a boot loader on an electronic device

1. A method, comprising:

invoking, using a non-overwritable primary boot loader on an electronic device, a boot selector stored on a write-protected permanent memory storage on the electronic device, wherein the non-overwritable primary boot loader and the boot selector are different pieces of software that are stored on different permanent memory storage devices on the electronic device;

selecting, using the boot selector, a secondary boot loader stored on the electronic device, wherein the secondary boot loader is selected by the boot selector between a backup boot loader and an upgradable boot loader, wherein the backup boot loader is stored on the same write-protected permanent memory storage device as the boot selector; and

executing the selected secondary boot loader to boot the electronic device.

2. The method of claim 1 , wherein selecting the secondary boot loader comprises:

searching for the upgradable boot loader stored on a writable-memory of the electronic device; and

if the upgradable boot loader is not found, selecting the backup boot loader stored on the permanent memory storage as the secondary boot loader.

3. The method of claim 2 , wherein selecting the secondary boot loader further comprises:

if the upgradable boot loader is found, determining whether the upgradable boot loader is corrupted;

if the upgradable boot loader is corrupted, selecting the backup boot loader stored on the permanent memory storage as the secondary boot loader; and

if the upgradable boot loader is not corrupted, selecting the upgradable boot loader as the secondary boot loader.

4. The method of claim 1 , wherein the non-overwritable primary boot loader is stored on a Read-Only Memory (ROM) of the electronic device.

5. The method of claim 1 , wherein the write-protected permanent memory storage is implemented using a write-protected embedded multimedia card (eMMC).

6. The method of claim 1 , further comprising outputting an optical signal indicating a status of a boot operation.

7. The method of claim 1 , wherein the secondary boot loader is selected based on a bypass signal.

8. An electronic device, comprising:

a Read-Only Memory (ROM) that stores a non-overwritable primary boot loader;

a write-protected permanent memory storage that stores a boot selector and a backup boot loader, wherein the non-overwritable primary boot loader and the boot selector are different pieces of software that are stored on different permanent memory storage devices on the electronic device; and

at least one hardware processor configured to:

invoke, by the non-overwritable primary boot loader, the boot selector;

select, by the boot selector, a secondary boot loader stored on the electronic device, wherein the secondary boot loader is selected by the boot selector between the backup boot loader and an upgradable boot loader; and

execute the selected secondary boot loader to boot the electronic device.

9. The electronic device of claim 8 , further comprising:

a writable-memory; and

wherein the at least one hardware processor is further configured to:

searching for the upgradable boot loader stored the writable-memory; and

if the upgradable boot loader is not found, select the backup boot loader stored on the permanent memory storage as the secondary boot loader.

10. The electronic device of claim 9 , wherein the at least one hardware processor is further configured to:

if the upgradable boot loader is found, determine whether the upgradable boot loader is corrupted;

if the upgradable boot loader is corrupted, select the backup boot loader stored on the permanent memory storage as the secondary boot loader; and

if the upgradable boot loader is not corrupted, select the upgradable boot loader as the secondary boot loader.

11. The electronic device of claim 8 , wherein the write-protected permanent memory storage is implemented using a write-protected embedded multimedia card (eMMC).

12. The electronic device of claim 8 , further comprising:

an optical output signal generator configured to output an optical signal indicating a status of a boot operation.

13. The electronic device of claim 8 , wherein the secondary boot loader is selected based on a bypass signal.

14. One or more non-transitory computer-readable media containing instructions which, when executed, cause an electronic device to perform operations comprising:

invoking, using a non-overwritable primary boot loader on the electronic device, a boot selector stored on a write-protected permanent memory storage on the electronic device, wherein the non-overwritable primary boot loader and the boot selector are different pieces of software that are stored on different permanent memory storage devices on the electronic device;

selecting, using the boot selector, a secondary boot loader stored on the electronic device, wherein the secondary boot loader is selected by the boot selector between a backup boot loader and an upgradable boot loader, wherein the backup boot loader is stored on the same write-protected permanent memory storage device as the boot selector; and

executing the selected secondary boot loader to boot the electronic device.

15. The one or more non-transitory computer-readable media of claim 14 , wherein selecting the secondary boot loader comprises:

searching for the upgradable boot loader stored on a writable-memory of the electronic device; and

if the upgradable boot loader is not found, selecting the backup boot loader stored on the permanent memory storage as the secondary boot loader.

16. The one or more non-transitory computer-readable media of claim 15 , wherein selecting the secondary boot loader further comprises:

if the upgradable boot loader is found, determining whether the upgradable boot loader is corrupted;

if the upgradable boot loader is corrupted, selecting the backup boot loader stored on the permanent memory storage as the secondary boot loader; and

if the upgradable boot loader is not corrupted, selecting the upgradable boot loader as the secondary boot loader.

17. The one or more non-transitory computer-readable media of claim 14 , wherein the non-overwritable primary boot loader is stored on a Read-Only Memory (ROM) of the electronic device.

18. The one or more non-transitory computer-readable media of claim 14 , wherein the write-protected permanent memory storage is implemented using a write-protected embedded multimedia card (eMMC).

19. The one or more non-transitory computer-readable media of claim 14 , the operations further comprising outputting an optical signal indicating a status of a boot operation.

20. The one or more non-transitory computer-readable media of claim 14 , wherein the secondary boot loader is selected based on a bypass signal.