/boot/dtbs/4.4.143-999-rockchip-g/rockchip/overlay/rockchip-fixup.scr文件的内容：

'V讳Wji萾謆? overlays fixup script
# implements (or rather substitutes) overlay arguments functionality
# using u-boot scripting, environment variables and "fdt" command

setenv decompose_pin 'setexpr tmp_pinctrl sub "GPIO(0|1|2|3|4)_\\S\\d+" "\\1";
setexpr tmp_bank sub "GPIO\\d_(\\S)\\d+" "\\1";
test "${tmp_bank}" = "A" && setenv tmp_bank 0;
test "${tmp_bank}" = "B" && setenv tmp_bank 1;
test "${tmp_bank}" = "C" && setenv tmp_bank 2;
test "${tmp_bank}" = "D" && setenv tmp_bank 3;
setexpr tmp_pin sub "GPIO\\d_\\S(\\d+)" "\\1";
setexpr tmp_bank ${tmp_bank} * 8;
setexpr tmp_pin ${tmp_bank} + ${tmp_pin}'

if test -n "${param_spidev_spi_bus}"; then
        test "${param_spidev_spi_bus}" = "0" && setenv tmp_spi_path "spi@ff120000"
        test "${param_spidev_spi_bus}" = "1" && setenv tmp_spi_path "spi@ff130000"
        test "${param_spidev_spi_bus}" = "2" && setenv tmp_spi_path "spi@ff140000"
        fdt set /${tmp_spi_path} status "okay"
        fdt set /${tmp_spi_path}/spidev status "okay"
        if test -n "${param_spidev_max_freq}"; then
                fdt set /${tmp_spi_path}/spidev spi-max-frequency "<${param_spidev_max_freq}>"
        fi
fi

if test -n "${param_w1_pin}"; then
        setenv tmp_pinctrl "${param_w1_pin}"
        setenv tmp_bank "${param_w1_pin}"
        setenv tmp_pin "${param_w1_pin}"
        run decompose_pin
        echo "${param_w1_pin} ---> pinctrl = ${tmp_pinctrl}"
        echo "${param_w1_pin} ---> bank = ${tmp_bank}"
        echo "${param_w1_pin} ---> pin = ${tmp_pin}"
        fdt get value tmp_pinctrl /__symbols__  gpio${tmp_pinctrl}
        echo "${param_w1_pin} ---> tmp_pinctrl = ${tmp_pinctrl}"
        fdt get value tmp_phandle ${tmp_pinctrl} phandle
        echo "${param_w1_pin} ---> tmp_phandle = ${tmp_phandle}"
        fdt set /onewire@0 gpios "<${tmp_phandle} ${tmp_pin} 0 0>"
        env delete tmp_pinctrl tmp_bank tmp_pin tmp_phandle
fi

=>

decompose_pin环境变量定义了但没有用到。

param_spidev_spi_bus和param_w1_pin环境变量不存在。

所以这个脚本没有任何用处。