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![Adam Ford](/assets/img/avatar_default.png)
With there now being four device tree files, and 4 separate defconfig files, the code necessary to determine which board is being used is no longer necessary as the corresponding pin-muxing and board names are determined by the device tree. Signed-off-by: Adam Ford <aford173@gmail.com>
57 lines
2.1 KiB
Plaintext
57 lines
2.1 KiB
Plaintext
Summary
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=======
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The source for omap3logic.c encompases the OMAP35 and DM3730 SOM-LV and DM3730 Torpedo platforms, but there are device trees custom taylored to each board.
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omap3_logic_defconfig = DM37 Torpedo / Torpedo + Wireless
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omap35_logic_defconfig = OMAP35 Torpedo
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omap3_logic_somlv_defconfig = DM37 SOM-LV
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omap35_logic_somlv_defconfig = OMAP35 SOM-LV
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The device tree included with each of the defconfig files will also direct the board as to which dtb file to load when loading the kernel, so it is not
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recomended to mix and match the defconfig files.
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Falcon Mode: FAT SD cards
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=========================
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In this case the additional file is written to the filesystem. In this
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example we assume that the uImage and device tree to be used are already on
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the FAT filesystem (only the uImage MUST be for this to function
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afterwards) along with a Falcon Mode aware MLO and the FAT partition has
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already been created and marked bootable:
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U-Boot # mmc rescan
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# Load kernel and device tree into memory, perform export
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U-Boot # fatload mmc 0 ${loadaddr} uImage
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U-Boot # run loadfdt
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U-Boot # setenv optargs quiet
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U-Boot # run mmcargs
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U-Boot # run common_bootargs
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U-Boot # spl export fdt ${loadaddr} - ${fdtaddr}
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This will print a number of lines and then end with something like:
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Loading Device Tree to 8dec9000, end 8dee0295 ... OK
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So then note the starting address and write the args to mmc/sd:
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U-Boot # fatwrite mmc 0:1 0x8dec9000 args 0x20000
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The size of 0x20000 matches the CMD_SPL_WRITE_SIZE.
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Falcon Mode: NAND
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=================
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In this case the additional data is written to another partition of the
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NAND. In this example we assume that the uImage and device tree to be are
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already located on the NAND somewhere (such as filesystem or mtd partition)
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along with a Falcon Mode aware MLO written to the correct locations for
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booting and mtdparts have been configured correctly for the board:
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U-Boot # nand read ${loadaddr} kernel
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U-Boot # load nand rootfs ${fdtaddr} /boot/am335x-evm.dtb
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U-Boot # run nandargs
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U-Boot # run common_bootargs
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U-Boot # spl export fdt ${loadaddr} - ${fdtaddr}
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U-Boot # nand erase.part u-boot-spl-os
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U-Boot # nand write ${fdtaddr} u-boot-spl-os
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