u-boot/doc/README.ublimage

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2 UBL image Boot Image generation using mkimage
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5 This document describes how to set up an U-Boot image that can be directly
6 booted by a DaVinci processor via NAND boot mode, using an UBL header,
9 For more details see section 11.2 "ARM ROM Boot Modes" of
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14 ./tools/mkimage -l <u-boot_file>
17 ./tools/mkimage -T ublimage \
18 		-n <board specific configuration file> \
19 		-d <u-boot binary>  <output image file>
22 ./tools/mkimage -n ./board/davinci/dm365evm/ublimage.cfg \
23 		-T ublimage \
24 		-d u-boot-nand.bin u-boot.ubl
26 You can generate the image directly when you compile u-boot with:
28 $ make u-boot.ubl
30 The output image can be flashed into the NAND.
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47 2. Following are the valid command strings and associated data strings:-
49 	--------------		-----------
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77 Structure of the u-boot.ubl binary:
84    -> u-boot-spl-16k.bin
88 2) compile u-boot.bin ("normal" u-boot)
89    -> u-boot.bin
91 3) create u-boot-nand.bin = u-boot-spl-16k.bin + u-boot.bin
93 4) create u-boot.ubl, size = 1 page size NAND
94    create UBL header and paste it before u-boot.bin
98 -> You get an u-boot.ubl binary, which you can flash
99    into your NAND.
101 Structure of this binary (Example for the cam_enc_4xx board with a NAND
105 content:    UBL     | nand_spl	  | u-boot code
108 The NAND layout looks for example like this:
110 (Example for the cam_enc_4xx board with a NAND page size = 0x800, block
114 content:    UBL     | nand_spl	  | u-boot code
121 If the cpu starts in NAND boot mode, it checks the UBL descriptor
124 bits of ARM internal memory (0x7ffc-0x8000).  This feature is provided
133 Once the user-specified start-up conditions are set, the RBL copies the
138 copies the u-boot code from NAND into RAM, and jumps to it ...
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