Das U-Boot
U-Boot for Surface RT.
You can use U-boot for tegra
git clone https://github.com/OE4T/u-boot-tegra; cd u-boot-tegra
or U-boot Mainline
git clone https://gitlab.denx.de/u-boot/u-boot.git; cd u-boot
THIS IS VERY IMPORTANT!!!
If you skip this step you can damage your device
Use the devicetree below. Don't use the devicetree from Linux.
Replace the content of
./arch/arm/dts/tegra30-cardhu.dts
with following code:/dts-v1/;
#include "tegra30.dtsi"
/ {
model = "NVIDIA Cardhu";
compatible = "nvidia,cardhu", "nvidia,tegra30";
chosen {
stdout-path = &uarta;
};
aliases {
mmc0 = "/sdhci@78000600";
mmc1 = "/sdhci@78000000";
};
memory {
device_type = "memory";
reg = <0x80000000 0x40000000>;
};
sdhci@78000000 {
status = "okay";
cd-gpios = <&gpio TEGRA_GPIO(I, 5) GPIO_ACTIVE_LOW>;
wp-gpios = <&gpio TEGRA_GPIO(T, 3) GPIO_ACTIVE_HIGH>;
power-gpios = <&gpio TEGRA_GPIO(D, 7) GPIO_ACTIVE_HIGH>;
bus-width = <4>;
};
sdhci@78000600 {
status = "okay";
bus-width = <8>;
non-removable;
};
clocks {
compatible = "simple-bus";
#address-cells = <1>;
#size-cells = <0>;
clk32k_in: clock@0 {
compatible = "fixed-clock";
reg=<0>;
#clock-cells = <0>;
clock-frequency = <32768>;
};
};
};
&uarta {
status = "okay";
};
Now you can build U-Boot:
make cardhu_defconfig
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-
Now you should find the file./u-boot-dtb-tegra.bin
This your Uboot Image which contains the SPL and Uboot.Booting Linux from UART is tedious and you may don't have UART access.
To automate the boot process a boot script can be used.
Create a file:
boot.script
echo 'Linux is booted from boot.scr'
setenv bootargs "console=tty0 root=/dev/mmcblk1p2 rootwait"
setenv kern_addr 0x80008000
fatload mmc 1:1 ${kern_addr} /zImage
fatload mmc 1:1 ${fdt_addr_r} /tegra30-microsoft-surface-rt.dtb
bootz ${kern_addr} - ${fdt_addr_r}
Compile it using:
mkimage -A arm -O linux -a 0 -e 0 -T script -C none -n "SurfaceRT Boot Script" -d boot.script boot.scr
Place
boot.scr
on the SD Card next to the kernel.
Tip: Don't hit any key to stop autoboot
Last modified 1yr ago