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Diffstat (limited to 'doc/README.hawkboard')
| -rw-r--r-- | doc/README.hawkboard | 43 |
1 files changed, 21 insertions, 22 deletions
diff --git a/doc/README.hawkboard b/doc/README.hawkboard index b7afec4..d6ae02e 100644 --- a/doc/README.hawkboard +++ b/doc/README.hawkboard @@ -9,8 +9,8 @@ executes upon reset is the Rom Boot Loader(RBL) which sits in the internal ROM of the omap. The RBL initialises the memory and the nand controller, and copies the image stored at a predefined location(block 1) of the nand flash. The image loaded by the RBL to the memory is the -AIS signed nand_spl image. This, in turns copies the u-boot binary -from the nand flash to the memory and jumps to the u-boot entry point. +AIS signed spl image. This, in turns copies the u-boot binary from the +nand flash to the memory and jumps to the u-boot entry point. AIS is an image format defined by TI for the images that are to be loaded to memory by the RBL. The image is divided into a series of @@ -20,14 +20,14 @@ and the size of the section, which is used by the RBL to load the image. At the end of the image the RBL jumps to the image entry point. -The secondary stage bootloader(nand_spl) which is loaded by the RBL -then loads the u-boot from a predefined location in the nand to the -memory and jumps to the u-boot entry point. +The secondary stage bootloader(spl) which is loaded by the RBL then +loads the u-boot from a predefined location in the nand to the memory +and jumps to the u-boot entry point. The reason a secondary stage bootloader is used is because the ECC layout expected by the RBL is not the same as that used by -u-boot/linux. This also implies that for flashing the nand_spl image, -we need to use the u-boot which uses the ECC layout expected by the +u-boot/linux. This also implies that for flashing the spl image,we +need to use the u-boot which uses the ECC layout expected by the RBL[1]. Booting u-boot over UART(UART boot) is explained here[2]. @@ -35,20 +35,19 @@ Compilation =========== Three images might be needed -* nand_spl - This is the secondary bootloader which boots the u-boot +* spl - This is the secondary bootloader which boots the u-boot binary. - hawkboard_nand_config - - The nand_spl ELF gets generated under nand_spl/u-boot-spl. This - needs to be processed with the AISGen tool for generating the AIS - signed image to be flashed. Steps for generating the AIS image are - explained here[3]. - * u-boot binary - This is the image flashed to the nand and copied to - the memory by the nand_spl. + the memory by the spl. + + Both the images get compiled with hawkboard_config, with the TOPDIR + containing the u-boot images, and the spl image under the spl + directory. - hawkboard_config + The spl image needs to be processed with the AISGen tool for + generating the AIS signed image to be flashed. Steps for generating + the AIS image are explained here[3]. * u-boot for uart boot - This is same as the u-boot binary generated above, with the sole difference of the CONFIG_SYS_TEXT_BASE being @@ -59,17 +58,17 @@ Three images might be needed Flashing the images to Nand =========================== -The nand_spl AIS image needs to be flashed to the block 1 of the -Nand flash, as that is the location the RBL expects the image[4]. For -flashing the nand_spl, boot over the u-boot specified in [1], and -flash the image +The spl AIS image needs to be flashed to the block 1 of the Nand +flash, as that is the location the RBL expects the image[4]. For +flashing the spl, boot over the u-boot specified in [1], and flash the +image => tftpboot 0xc0700000 <nand_spl_ais.bin> => nand erase 0x20000 0x20000 => nand write.e 0xc0700000 0x20000 <nand_spl_size> The u-boot binary is flashed at location 0xe0000(block 6) of the nand -flash. The nand_spl loader expects the u-boot at this location. For +flash. The spl loader expects the u-boot at this location. For flashing the u-boot binary => tftpboot 0xc0700000 u-boot.bin |