boot-time device tree overlays with U-Boot
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part uuid ${devtype} ${devnum}:${bootpart} uuid |
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setenv bootargs console=${console} root=PARTUUID=${uuid} rw rootwait |
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if load ${devtype} ${devnum}:${bootpart} ${kernel_addr_r} /boot/zImage; then |
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if load ${devtype} ${devnum}:${bootpart} ${fdt_addr_r} /boot/dtbs/${fdtfile}; then |
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fdt addr ${fdt_addr_r} |
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fdt resize |
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setexpr fdtovaddr ${fdt_addr_r} + F000 |
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if load ${devtype} ${devnum}:${bootpart} ${fdtovaddr} /boot/dtbs/overlay.txt && env import -t ${fdtovaddr} ${filesize} && test -n ${overlay}; then |
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echo loaded overlay.txt: ${overlay} |
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for ov in ${overlay}; do |
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echo overlaying ${ov}... |
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load ${devtype} ${devnum}:${bootpart} ${fdtovaddr} /boot/dtbs/${ov}.dtb && fdt apply ${fdtovaddr} |
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done |
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fi |
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if load ${devtype} ${devnum}:${bootpart} ${ramdisk_addr_r} /boot/initramfs-linux.img; then |
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bootz ${kernel_addr_r} ${ramdisk_addr_r}:${filesize} ${fdt_addr_r}; |
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else |
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bootz ${kernel_addr_r} - ${fdt_addr_r}; |
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fi; |
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fi; |
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fi |
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/dts-v1/; |
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/plugin/; |
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/ { |
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compatible = "allwinner,sun7i-a20"; |
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fragment@0 { |
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target = <&i2c2>; |
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__overlay__ { |
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#address-cells = <1>; |
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#size-cells = <0>; |
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ina219@40 { |
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status = "okay"; |
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compatible = "ti,ina219"; |
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reg = <0x40>; |
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shunt-resistor = <100000>; // R100 |
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}; |
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}; |
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}; |
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}; |
