From: Heinrich Schuchardt Date: Wed, 16 Apr 2025 06:44:29 +0000 (+0200) Subject: doc: dt_qemu: correct dumpdtb description X-Git-Tag: v2025.07-rc1~48^2~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=67d5b4a42b123c02a20963b260908f449a0004c8;p=pandora-u-boot.git doc: dt_qemu: correct dumpdtb description Use only a single -machine parameter. Describe that the same invocation of qemu-system- has to be used for dumping the device-tree as will be used when executing U-Boot. Signed-off-by: Heinrich Schuchardt --- diff --git a/doc/develop/devicetree/dt_qemu.rst b/doc/develop/devicetree/dt_qemu.rst index 8ba2b225590..b452e2a997a 100644 --- a/doc/develop/devicetree/dt_qemu.rst +++ b/doc/develop/devicetree/dt_qemu.rst @@ -16,15 +16,22 @@ Obtaining the QEMU devicetree Where QEMU generates its own devicetree to pass to U-Boot you can use `-dtb u-boot.dtb` to force QEMU to use U-Boot's in-tree version. -To obtain the devicetree that qemu generates, add `-machine dumpdtb=qemu.dtb`, -e.g.:: - - qemu-system-arm -machine virt -machine dumpdtb=qemu.dtb - - qemu-system-aarch64 -machine virt -machine dumpdtb=qemu.dtb - - qemu-system-riscv64 -machine virt -machine dumpdtb=qemu.dtb - +To obtain the devicetree that QEMU generates, add `dumpdtb=qemu.dtb` to the +`-machine` argument, e.g. + +.. code-block:: bash + + qemu-system-aarch64 \ + -machine virt,gic-version=3,dumpdtb=qemu.dtb \ + -cpu cortex-a57 \ + -smp 4 \ + -memory 8G \ + -chardev socket,id=chrtpm,path=/tmp/mytpm1/swtpm-sock \ + -tpmdev emulator,id=tpm0,chardev=chrtpm \ + -device tpm-tis-device,tpmdev=tpm0 + +Except for the dumpdtb=qemu.dtb sub-parameter use the same qemu-system- +invocation that you would use to start U-Boot to to get a complete device-tree. Merging in U-Boot nodes/properties ----------------------------------