rebuilding RedBoot RedBootrebuilding RedBoot is built as an application on top of eCos. The makefile rules for building RedBoot are part of the eCos CDL package, so it's possible to build eCos from the Configuration Tool, as well as from the command line using ecosconfig. Building RedBoot requires only a few steps: selecting the platform and the RedBoot template, importing a platform specific configuration file, and finally starting the build. The platform specific configuration file makes sure the settings are correct for building RedBoot on the given platform. Each platform should provide at least two of these configuration files: redboot_RAM.ecm for a RAM mode RedBoot configuration and redboot_ROM.ecm or redboot_ROMRAM.ecm for a ROM or ROMRAM mode RedBoot configuration. There may be additional configuration files according to the requirements of the particular platform. The RedBoot build process results in a number of files in the install bin directory. The ELF file redboot.elf is the pricipal result. Depending on the platform CDL, there will also be generated versions of RedBoot in other file formats, such as redboot.bin (binary format, good when doing an update of a primary RedBoot image, see ), redboot.srec (Motorola S-record format, good when downloading a RAM mode image for execution), and redboot.img (stripped ELF format, good when downloading a RAM mode image for execution, smaller than the .srec file). Some platforms may provide additional file formats and also relocate some of these files to a particular address making them more suitable for downloading using a different boot monitor or flash programming tools. The platform specific information in should be consulted, as there may be other special instructions required to build RedBoot for particular platforms. To rebuild RedBoot using the ecosconfig tool, create a temporary directory for building RedBoot, name it according to the desired configuration of RedBoot, here RAM: $ mkdir /tmp/redboot_RAM $ cd /tmp/redboot_RAM Create the build tree according to the chosen platform, here using the Hitachi Solution Engine 7751 board as an example: It is assumed that the environment variable ECOS_REPOSITORY points to the eCos/RedBoot source tree. $ ecosconfig new se7751 redboot U CYGPKG_HAL_SH_7750, new inferred value 0 U CYGPKG_HAL_SH_7751, new inferred value 1 U CYGHWR_HAL_SH_IRQ_USE_IRQLVL, new inferred value 1 U CYGSEM_HAL_USE_ROM_MONITOR, new inferred value 0 U CYGDBG_HAL_COMMON_CONTEXT_SAVE_MINIMUM, new inferred value 0 U CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS, new inferred value 1 U CYGFUN_LIBC_STRING_BSD_FUNCS, new inferred value 0 U CYGPKG_NS_DNS_BUILD, new inferred value 0 Replace the platform name ("se7751") with the appropriate name for the chosen platform. Then import the appropriate platform RedBoot configuration file, here for RAM configuration: $ ecosconfig import ${ECOS_REPOSITORY}/hal/sh/se7751/VERSION/misc/redboot_RAM.ecm $ ecosconfig tree Replace architecture ("sh"), platform ("se7751") and version ("VERSION") with those appropriate for the chosen platform and the version number of its HAL package. Also replace the configuration name ("redboot_RAM.ecm") with that of the appropriate configuration file. RedBoot can now be built: $ make The resulting RedBoot files will be in the associated install directory, in this example, ./install/bin. In each platform's details are described in the form of shell variables. Using those, the steps to build RedBoot are: export REDBOOT_CFG=redboot_ROM export VERSION=VERSION mkdir /tmp/${REDBOOT_CFG} cd /tmp/${REDBOOT_CFG} ecosconfig new ${TARGET} redboot ecosconfig import ${ECOS_REPOSITORY}/hal/${ARCH_DIR}/${PLATFORM_DIR}/${VERSION}/misc/${REDBOOT_CFG}.ecm ecosconfig tree make To build for another configuration, simply change the REDBOOT_CFG definition accordingly. Also make sure the VERSION variable matches the version of the platform package. To rebuild RedBoot from the Configuration Tool, open the template window (Build->Templates) and select the appropriate Hardware target and in Packages select "redboot". Then press OK. Depending on the platform, a number of conflicts may need to be resolved before the build can be started; select "Continue". Import the desired RedBoot configuration file from the platform HAL (File->Import...). Depending on the platform, a number of conflicts may need to be resolved before the build can be started; select "Continue". For example, if the platform selected is Hitachi SE7751 board and the RAM configuration RedBoot should be built, import the file hal/sh/se7751/VERSION/misc/redboot_RAM.ecm. Save the configuration somewhere suitable with enough disk space for building RedBoot (File->Save...). Choose the name according to the RedBoot configuration, for example redboot_RAM.ecc. Then start the build (Build->Library) and wait for it to complete. The resulting RedBoot files will be in the associated install directory, for the example this would be redboot_RAM_install/bin. As noted above, each platform's details are described in . Use the information provided in the shell variables to find the configuration file - the path to it is ${ECOS_REPOSITORY}/hal/${ARCH_DIR}/${PLATFORM_DIR}/${VERSION}/misc/${REDBOOT_CFG}.ecm, where ECOS_REPOSITORY points to the eCos/RedBoot sources, VERSION is the version of the package (usually "current") and REDBOOT_CFG is the desired configuration, e.g. redboot_RAM. updating RedBoot RedBootupdatingRedBoot normally resides in an EPROM or, more common these days, a flash on the board. In the former case, updating RedBoot necessitates physically removing the part and reprogramming a new RedBoot image into it using prommer hardware. In the latter case, it is often possible to update RedBoot in situ using Redboot's flash management commands. The process of updating RedBoot in situ is documented in this section. For this process, it is assumed that the target is connected to a host system and that there is a serial connection giving access to the RedBoot CLI. For platforms with a ROMRAM mode RedBoot, skip to . The addresses and sizes included in the below are examples only, and will differ from those you will see. This is normal and should not cause concern. There are a number of choices here. The basic case is where a RAM mode image has been stored in the FIS (flash Image System). To load and execute this image, use the commands: RedBoot> fis load RedBoot[RAM] RedBoot> go If this image is not available, or does not work, then an alternate RAM mode image must be loaded: RedBoot> load redboot_RAM.img Entry point: 0x060213c0, address range: 0x06020000-0x060369c8 RedBoot> go This command loads the RedBoot image using the TFTP protocol via a network connection. Other methods of loading are available, refer to the load command for more details. If you expect to be doing this more than once, it is a good idea to program the RAM mode image into the flash. You do this using the fis create command after having downloaded the RAM mode image, but before you start it. Some platforms support locking (write protecting) certain regions of the flash, while others do not. If your platform does not support locking, simply ignore the fis unlock and fis lock steps (the commands will not be recognized by RedBoot). RedBoot> fis unlock RedBoot[RAM] ... Unlock from 0x00000000-0x00020000: .. RedBoot> fis create RedBoot[RAM] An image named 'RedBoot[RAM]' exists - continue (y/n)? y * CAUTION * about to program 'RedBoot[RAM]' at 0x00020000..0x000369c7 from 0x06020000 - continue (y/n)?y ... Erase from 0x00020000-0x00040000: .. ... Program from 0x06020000-0x060369c8 at 0x00020000: .. ... Erase from 0x00070000-0x00080000: . ... Program from 0x0606f000-0x0607f000 at 0x00070000: . RedBoot> fis lock RedBoot[RAM] ... Lock from 0x00000000-0x00020000: .. An instance of RedBoot should now be running on the target from RAM. This can be verified by looking for the mode identifier in the banner. It should be either [RAM] or [ROMRAM]. If this is the first time RedBoot is running on the board or if the flash contents has been damaged, initialize the FIS directory: RedBoot> fis init -f About to initialize [format] FLASH image system - continue (y/n)? y *** Initialize FLASH Image System ... Erase from 0x00020000-0x00070000: ..... ... Erase from 0x00080000-0x00080000: ... Erase from 0x00070000-0x00080000: . ... Program from 0x0606f000-0x0607f000 at 0x00070000: . It is important to understand that the presence of a correctly initialized FIS directory allows RedBoot to automatically determine the flash parameters. Additionally, executing the steps below as stated without loading other data or using other flash commands (than possibly fis list) allows RedBoot to automatically determine the image location and size parameters. This greatly reduces the risk of potential critical mistakes due to typographical errors. It is still always possible to explicitly specify parameters, and indeed override these, but it is not advised. If the new RedBoot image has grown beyond the slot in flash reserved for it, it is necessary to change the RedBoot configuration option CYGBLD_REDBOOT_MIN_IMAGE_SIZE so the FIS is created with adequate space reserved for RedBoot images. In this case, it is necessary to re-initialize the FIS directory as described above, using a RAM mode RedBoot compiled with the updated configuration. Using the load command, download the new flash based image from the host, relocating the image to RAM:: RedBoot> load -r -b %{FREEMEMLO} redboot_ROM.bin Raw file loaded 0x06046800-0x06062fe8, assumed entry at 0x06046800 This command loads the RedBoot image using the TFTP protocol via a network connection. Other methods of loading are available, refer to the command for more details. Note that the binary version of the image is being downloaded. This is to ensure that the memory after the image is loaded should match the contents of the file on the host. Loading SREC or ELF versions of the image does not guarantee this since these formats may contain holes, leaving bytes in these holes in an unknown state after the load, and thus causing a likely cksum difference. It is possible to use these, but then the step verifying the cksum below may fail. Once the image is loaded into RAM, it should be checksummed, thus verifying that the image on the target is indeed the image intended to be loaded, and that no corruption of the image has happened. This is done using the command: RedBoot> cksum Computing cksum for area 0x06046800-0x06062fe8 POSIX cksum = 2535322412 116712 (0x971df32c 0x0001c7e8) Compare the numbers with those for the binary version of the image on the host. If they do not match, try downloading the image again. Assuming the cksum matches, the next step is programming the image into flash using the FIS commands. Some platforms support locking (write protecting) certain regions of the flash, while others do not. If your platform does not support locking, simply ignore the fis unlock and fis lock steps (the commands will not be recognized by RedBoot). RedBoot> fis unlock RedBoot ... Unlock from 0x00000000-0x00020000: .. RedBoot> fis create RedBoot An image named 'RedBoot' exists - continue (y/n)? y * CAUTION * about to program 'RedBoot' at 0x00000000..0x0001c7e7 from 0x06046800 - continue (y/n)? y ... Erase from 0x00000000-0x00020000: .. ... Program from 0x06046800-0x06062fe8 at 0x00000000: .. ... Erase from 0x00070000-0x00080000: . ... Program from 0x0606f000-0x0607f000 at 0x00070000: . RedBoot> fis lock RedBoot ... Lock from 0x00000000-0x00020000: .. Once the image has been successfully written into the flash, simply reset the target and the new version of RedBoot should be running. When installing RedBoot for the first time, or after updating to a newer RedBoot with different configuration keys, it is necessary to update the configuration directory in the flash using the fconfig command. See .