1*d80162cfSPantelis AntoniouU-Boot FDT Overlay usage (without FIT images) 2*d80162cfSPantelis Antoniou============================================= 3*d80162cfSPantelis Antoniou 4*d80162cfSPantelis AntoniouFDT overlays are now available for use even without FIT images. 5*d80162cfSPantelis AntoniouIt is not as automagic as with FIT images though and require a few 6*d80162cfSPantelis Antonioumanual steps. 7*d80162cfSPantelis Antoniou 8*d80162cfSPantelis Antoniou1. Figure out where to place both the base device tree blob and the 9*d80162cfSPantelis Antoniouoverlay. Make sure you have enough space to grow the base tree without 10*d80162cfSPantelis Antoniouoverlapping anything. 11*d80162cfSPantelis Antoniou 12*d80162cfSPantelis Antoniou=> setenv fdtaddr 0x87f00000 13*d80162cfSPantelis Antoniou=> setenv fdtovaddr 0x87fc0000 14*d80162cfSPantelis Antoniou 15*d80162cfSPantelis Antoniou2. Load the base blob and overlay blobs 16*d80162cfSPantelis Antoniou 17*d80162cfSPantelis Antoniou=> load ${devtype} ${bootpart} ${fdtaddr} ${bootdir}/base.dtb 18*d80162cfSPantelis Antoniou=> load ${devtype} ${bootpart} ${fdtovaddr} ${bootdir}/overlay.dtb 19*d80162cfSPantelis Antoniou 20*d80162cfSPantelis Antoniou3. Set it as the working fdt tree. 21*d80162cfSPantelis Antoniou 22*d80162cfSPantelis Antoniou=> fdtaddr $fdtaddr 23*d80162cfSPantelis Antoniou 24*d80162cfSPantelis Antoniou4. Grow it enough so it can 'fit' all the applied overlays 25*d80162cfSPantelis Antoniou 26*d80162cfSPantelis Antoniou=> fdt resize 8192 27*d80162cfSPantelis Antoniou 28*d80162cfSPantelis Antoniou5. You are now ready to apply the overlay. 29*d80162cfSPantelis Antoniou 30*d80162cfSPantelis Antoniou=> fdt apply $fdtovaddr 31*d80162cfSPantelis Antoniou 32*d80162cfSPantelis AntoniouPlease note that in case of an error, both the base and overlays are going 33*d80162cfSPantelis Antoniouto be invalidated, so keep copies to avoid reloading. 34*d80162cfSPantelis Antoniou 35*d80162cfSPantelis AntoniouPantelis Antoniou 36*d80162cfSPantelis Antonioupantelis.antoniou@konsulko.com 37*d80162cfSPantelis Antoniou11/7/2017 38