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Diffstat (limited to 'board/gateworks/gw_ventana/README')
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diff --git a/board/gateworks/gw_ventana/README b/board/gateworks/gw_ventana/README index 9e697d6199..888657cb0c 100644 --- a/board/gateworks/gw_ventana/README +++ b/board/gateworks/gw_ventana/README @@ -3,53 +3,81 @@ U-Boot for the Gateworks Ventana Product Family boards This file contains information for the port of U-Boot to the Gateworks Ventana Product family boards. -1. Boot source, boot from NAND +1. Secondary Program Loader (SPL) +--------------------------------- + +The i.MX6 has a BOOT ROM PPL (Primary Program Loader) which supports loading +an executable image from various boot devices. + +The Gateworks Ventana board config uses an SPL build configuration. This +will build the following artifacts from u-boot source: + - SPL - Secondary Program Loader that the i.MX6 BOOT ROM (Primary Program + Loader) boots. This detects CPU/DRAM configuration, configures + The DRAM controller, loads u-boot.img from the detected boot device, + and jumps to it. As this is booted from the PPL, it has an IVT/DCD + table. + - u-boot.img - The main u-boot core which is u-boot.bin with a image header. + + +2. Build +-------- + +To build U-Boot for the Gateworks Ventana product family: + + make gwventana_config + make + + +3. Boot source, boot from NAND ------------------------------ The i.MX6 BOOT ROM expects some structures that provide details of NAND layout and bad block information (referred to as 'bootstreams') which are replicated -multiple times in NAND. The number of replications is configurable through -board strapping options and eFUSE settings. The Freescale 'kobs-ng' -application from the Freescale LTIB BSP, which runs under Linux, must be used -to program the bootstream in order to setup the replicated headers correctly. +multiple times in NAND. The number of replications and their spacing (referred +to as search stride) is configurable through board strapping options and/or +eFUSE settings (BOOT_SEARCH_COUNT / Pages in block from BOOT_CFG2). In +addition, the i.MX6 BOOT ROM Flash Configuration Block (FCB) supports two +copies of a bootloader in flash in the case that a bad block has corrupted one. +The Freescale 'kobs-ng' application from the Freescale LTIB BSP, which runs +under Linux and operates on an MTD partition, must be used to program the +bootstream in order to setup this flash structure correctly. The Gateworks Ventana boards with NAND flash have been factory programmed such that their eFUSE settings expect 2 copies of the boostream (this is specified by providing kobs-ng with the --search_exponent=1 argument). Once in -Linux with MTD support for the NAND on /dev/mtd0 you can program the boostream +Linux with MTD support for the NAND on /dev/mtd0 you can program the SPL with: -kobs-ng init -v -x --search_exponent=1 u-boot.imx +kobs-ng init -v -x --search_exponent=1 SPL -The kobs-ng application uses an imximage (u-boot.imx) which contains the -Image Vector Table (IVT) and Device Configuration Data (DCD) structures that -the i.MX6 BOOT ROM requires to boot. The kobs-ng adds the Firmware -Configuration Block (FCB) and Discovered Bad Block Table (DBBT). +The kobs-ng application uses an imximage which contains the Image Vector Table +(IVT) and Device Configuration Data (DCD) structures that the i.MX6 BOOT ROM +requires to boot. The kobs-ng adds the Firmware Configuration Block (FCB) and +Discovered Bad Block Table (DBBT). The SPL build artifact from u-boot is +an imximage. -This information is taken from: - http://trac.gateworks.com/wiki/ventana/bootloader#NANDFLASH +The u-boot.img, which is the non SPL u-boot binary appended to a u-boot image +header must be programmed in the NAND flash boot device at an offset hard +coded in the SPL. For the Ventana boards, this has been chosen to be 14MB. +The image can be programmed from either u-boot or Linux: -More details about the i.MX6 BOOT ROM can be found in the IMX6 reference manual. - -2. Build --------- +u-boot: +Ventana > setenv mtdparts mtdparts=nand:14m(spl),2m(uboot),1m(env),-(rootfs) +Ventana > tftp ${loadaddr} u-boot.img && nand erase.part uboot && \ + nand write ${loadaddr} uboot ${filesize} -There are several Gateworks Ventana boards that share a simliar design but -vary based on CPU, Memory configuration, and subloaded devices. Although -the subloaded devices are handled dynamically in the bootloader using -factory configured EEPROM data to modify the device-tree, the CPU choice -(IMX6Q vs IMX6DL) and memory configurations are currently compile-time -options. +Linux: +nandwrite /dev/mtd1 u-boot.img -The following Gateworks Ventana configurations exist: - gwventanaq1gspi: MX6Q,1GB,SPI FLASH - gwventanaq : MX6Q,512MB,NAND FLASH - gwventanaq1g : MX6Q,1GB,NAND FLASH - gwventanadl : MX6DL,512MB,NAND FLASH - gwventanadl1g : MX6DL,1GB,NAND FLASH +The above assumes the default Ventana partitioning scheme which is configured +via the mtdparts env var: + - spl: 14MB + - uboot: 2M + - env: 1M + - rootfs: the rest -To build U-Boot for the MX6Q,1GB,NAND FLASH for example: +This information is taken from: + http://trac.gateworks.com/wiki/ventana/bootloader#NANDFLASH - make gwventanaq1g_config - make +More details about the i.MX6 BOOT ROM can be found in the IMX6 reference manual. |
