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+U-Boot FDT Overlay usage (without FIT images)
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+=============================================
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+
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+FDT overlays are now available for use even without FIT images.
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+It is not as automagic as with FIT images though and require a few
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+manual steps.
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+
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+1. Figure out where to place both the base device tree blob and the
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+overlay. Make sure you have enough space to grow the base tree without
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+overlapping anything.
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+
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+=> setenv fdtaddr 0x87f00000
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+=> setenv fdtovaddr 0x87fc0000
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+
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+2. Load the base blob and overlay blobs
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+
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+=> load ${devtype} ${bootpart} ${fdtaddr} ${bootdir}/base.dtb
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+=> load ${devtype} ${bootpart} ${fdtovaddr} ${bootdir}/overlay.dtb
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+
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+3. Set it as the working fdt tree.
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+
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+=> fdtaddr $fdtaddr
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+
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+4. Grow it enough so it can 'fit' all the applied overlays
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+
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+=> fdt resize 8192
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+
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+5. You are now ready to apply the overlay.
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+
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+=> fdt apply $fdtovaddr
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+
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+Please note that in case of an error, both the base and overlays are going
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+to be invalidated, so keep copies to avoid reloading.
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+
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+Pantelis Antoniou
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+pantelis.antoniou@konsulko.com
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+11/7/2017
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