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+README on how boot images are created for secure TI devices
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+
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+CONFIG_TI_SECURE_DEVICE:
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+Secure TI devices require a boot image that is authenticated by ROM
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+code to function. Without this, even JTAG remains locked and the
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+device is essentially useless. In order to create a valid boot image for
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+a secure device from TI, the initial public software image must be signed
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+and combined with various headers, certificates, and other binary images.
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+
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+Information on the details on the complete boot image format can be obtained
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+from Texas Instruments. The tools used to generate boot images for secure
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+devices are part of a secure development package (SECDEV) that can be
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+downloaded from:
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+
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+ http://www.ti.com/mysecuresoftware (login required)
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+
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+The secure development package is access controlled due to NDA and export
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+control restrictions. Access must be requested and granted by TI before the
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+package is viewable and downloadable. Contact TI, either online or by way
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+of a local TI representative, to request access.
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+
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+When CONFIG_TI_SECURE_DEVICE is set, the U-Boot SPL build process requires
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+the presence and use of these tools in order to create a viable boot image.
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+The build process will look for the environment variable TI_SECURE_DEV_PKG,
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+which should be the path of the installed SECDEV package. If the
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+TI_SECURE_DEV_PKG variable is not defined or if it is defined but doesn't
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+point to a valid SECDEV package, a warning is issued during the build to
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+indicate that a final secure bootable image was not created.
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+
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+Within the SECDEV package exists an image creation script:
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+
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+${TI_SECURE_DEV_PKG}/scripts/create-boot-image.sh
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+
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+This is called as part of the SPL/u-boot build process. As the secure boot
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+image formats and requirements differ between secure SOC from TI, the
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+purpose of this script is to abstract these details as much as possible.
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+
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+The script is basically the only required interface to the TI SECDEV package
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+for secure TI devices.
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+
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+Invoking the script for AM43xx Secure Devices
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+=============================================
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+
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+create-boot-image.sh <IMAGE_FLAG> <INPUT_FILE> <OUTPUT_FILE> <SPL_LOAD_ADDR>
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+
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+<IMAGE_FLAG> is a value that specifies the type of the image to generate OR
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+the action the image generation tool will take. Valid values are:
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+ SPI_X-LOADER - Generates an image for SPI flash (byte swapped)
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+ XIP_X-LOADER - Generates a single stage u-boot for NOR/QSPI XiP
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+ ISSW - Generates an image for all other boot modes
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+
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+<INPUT_FILE> is the full path and filename of the public world boot loader
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+binary file (depending on the boot media, this is usually either
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+u-boot-spl.bin or u-boot.bin).
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+
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+<OUTPUT_FILE> is the full path and filename of the final secure image. The
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+output binary images should be used in place of the standard non-secure
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+binary images (see the platform-specific user's guides and releases notes
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+for how the non-secure images are typically used)
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+ u-boot-spl_HS_SPI_X-LOADER - byte swapped boot image for SPI flash
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+ u-boot_HS_XIP_X-LOADER - boot image for NOR or QSPI flash
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+ u-boot-spl_HS_ISSW - boot image for all other boot media
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+
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+<SPL_LOAD_ADDR> is the address at which SOC ROM should load the <INPUT_FILE>
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+
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+Invoking the script for DRA7xx/AM57xx Secure Devices
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+====================================================
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+
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+create-boot-image.sh <IMAGE_TYPE> <INPUT_FILE> <OUTPUT_FILE>
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+
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+<IMAGE_TYPE> is a value that specifies the type of the image to generate OR
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+the action the image generation tool will take. Valid values are:
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+ X-LOADER - Generates an image for NOR or QSPI boot modes
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+ MLO - Generates an image for SD/MMC/eMMC boot modes
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+ ULO - Generates an image for USB/UART peripheral boot modes
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+ Note: ULO is not yet used by the u-boot build process
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+
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+<INPUT_FILE> is the full path and filename of the public world boot loader
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+binary file (for this platform, this is always u-boot-spl.bin).
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+
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+<OUTPUT_FILE> is the full path and filename of the final secure image. The
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+output binary images should be used in place of the standard non-secure
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+binary images (see the platform-specific user's guides and releases notes
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+for how the non-secure images are typically used)
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+ u-boot-spl_HS_MLO - boot image for SD/MMC/eMMC. This image is
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+ copied to a file named MLO, which is the name that
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+ the device ROM bootloader requires for loading from
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+ the FAT partition of an SD card (same as on
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+ non-secure devices)
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+ u-boot-spl_HS_X-LOADER - boot image for all other flash memories
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+ including QSPI and NOR flash
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