Hermit-At is a functional downloader and bootloader used on Atmark Techno products. The Hermit-At bootloader prompt is displayed when an Armadillo board is booted in maintenance mode. From the prompt it is possible to enter commands for a variety of operations such as updating flash memory and setting Linux kernel parameters. The following gives details on the most well used functions.
This command displays version information.
This command displays board information.
This command displays the flash memory and DRAM memory map.
This command displays the MAC address.
This command calculates and displays the md5sum value of the specified memory region.
To calculate and display the md5sum value of the first 1024 bytes of the bootloader region, execute the command shown in 図A.10「md5sum Example」.
This command erases flash memory.
These commands are used to set Linux kernel parameters. The parameters set with setenv are passed to the kernel at boot time. Executing clearenv clears any configuration. The parameters are saved in flash memory and are therefore maintained even after rebooting.
A.7.1. setenv/clearenv Example
A.7.2. Linux Kernel Parameters
Example Linux kernel parameters are shown in 表A.1「Well Used Linux Kernel Parameters」. For information on other options, please refer to linux-2.6/Documentation/kernel-parameters.txt.
表A.1 Well Used Linux Kernel Parameters
| Option | Description |
|---|
| console | Specify device to be used for kernel console. |
| root | Specify root filesystem related settings. |
| rootdelay | Seconds to wait before attempting to mount root filesystem. |
| rootwait | Wait until the root filesystem is accessible before attempting to mount it. |
| noinitrd | Specify what should happen with the initrd data after the kernel has booted. |
| nfsroot | Specify root filesystem place and NFS options when using NFS. |
![[警告]](images/warning.png) | |
|---|
When ttymxc1,2,4 is specified for the console option, the serial interface used by Hermit-At will also change to that interface after the next boot. |
This command is used to specify the boot device holding the Linux kernel. This setting is saved in flash memory and is therefore maintained even after rebooting.
This command is used to enter a mode for reading or altering data at a specified address.
表A.2 frob Command
| frob Command | Description |
|---|
| peek [addr] | Read 32bit data from specified address |
| peek16 [addr] | Read 16bit data from specified address |
| peek8 [addr] | Read 8bit data from specified address |
| poke [addr] [value] | Write 32bit data to specified address |
| poke16 [addr] [value] | Write 16bit data to specified address |
| poke8 [addr] [value] | Write 8bit data to specified address |
This command is used to download an image file from a TFTP server and write it to flash memory.
表A.3 tftpdl Options
| Option | Description |
|---|
--bootloader=filepath | Specify file to be written to the bootloader region in place of filepath. |
--kernel=filepath | Specify file to be written to the kernel region in place of filepath. |
--userland=filepath | Specify file to be written to the userland region in place of filepath. |
| --fake | Download the files, but do not actually write the files to flash memory. |
This command is used to download an image file from a TFTP server, extract it to RAM and then boot it. As opposed to the tftpdl command, the file is not written to flash memory. Also, the settings are not saved like they are when using the setbootdevice command.
The same options as shown in 表A.3「tftpdl Options」 can be used with this command. When --fake is specified, the file is downloaded but not booted.
| The kernel and userland images are being extracted to RAM. |
| The kernel is booted and kernel boot log displayed. |
This command boots the Linux kernel image from the boot device specified with the setbootdevice command.
| The kernel and userland images are being extracted to RAM. |
| Kernel parameters set with the setenv command are displayed. All messages up to this point are from Hermit-At. |
| The kernel is booted and kernel boot log displayed. |
When a bootloader image based on hermit-at v2.0.0 source (loader-armadillo4x0-v2.0.0.bin etc) and a kernel image based on linux-2.6.26-at7 source (linux-a400-1.00.bin.gz etc) are used on Armadillo-440 Rev.C1 or later boards (S/N 100201-2195 or greater), a problem exists where the kernel may not boot. This problem only occurs with the above combination.
On Armadillo-440 Rev.C1 or later boards (S/N 100201-2195 and greater), please use a bootloader image based on hermit-at v2.0.1 or later source (loader-armadillo4x0-v2.0.1.bin or later).[]
