Difference between revisions of "ImageBuilder"

From Xen
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= Booting Xen from U-Boot =
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Booting Xen from U-Boot requires:
 
Booting Xen from U-Boot requires:
   
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See [https://xenbits.xenproject.org/docs/unstable/misc/arm/device-tree/booting.txt booting.txt] as a reference.
 
See [https://xenbits.xenproject.org/docs/unstable/misc/arm/device-tree/booting.txt booting.txt] as a reference.
   
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= ImageBuilder =
The processing is complex and cumbersome. To automate this configuration steps you can use ImageBuilder:
 
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The whole process can be automated with '''ImageBuilder''':
   
 
[https://gitlab.com/ViryaOS/imagebuilder https://gitlab.com/ViryaOS/imagebuilder]
 
[https://gitlab.com/ViryaOS/imagebuilder https://gitlab.com/ViryaOS/imagebuilder]
   
ImageBuilder can be invoked as a container for build automation, but its useful scripts can also be called manually. Specifically, '''script/uboot-script-gen''' generates a U-Boot script that loads all the necessary binaries and automatically adds the required entries to device tree at boot time.
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ImageBuilder can be invoked as a container for build automation, but its useful scripts can also be called manually. Specifically, '''script/uboot-script-gen''' generates a U-Boot script that loads all the necessary binaries and automatically adds the required entries to device tree at boot time. In order to use it, you need to write a config file first.
   
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== Config file ==
First write a config file, like the following:
 
   
 
<nowiki>
 
<nowiki>
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The fields are self explanatory but you can find more detailed information on the [https://gitlab.com/ViryaOS/imagebuilder/blob/master/README.md readme]. Make sure to use raw binaries for Xen, all the kernels and rootfs's, not U-Boot binaries (do '''not''' use the output of mkimage).
 
The fields are self explanatory but you can find more detailed information on the [https://gitlab.com/ViryaOS/imagebuilder/blob/master/README.md readme]. Make sure to use raw binaries for Xen, all the kernels and rootfs's, not U-Boot binaries (do '''not''' use the output of mkimage).
   
Then you can call uboot-script-gen as follows:
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== uboot-script-gen ==
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Once you have the config file, you can call uboot-script-gen as follows:
   
 
<nowiki>
 
<nowiki>
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$ export LOAD_CMD="load scsi 0:1"
 
$ export LOAD_CMD="load scsi 0:1"
 
$ bash ./scripts/uboot-script-gen /path/to/config
 
$ bash ./scripts/uboot-script-gen /path/to/config
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</nowiki>
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= Important Notes =
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== Xen and Dom0 command line ==
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ImageBuilder uses sched=null by default. If you want to change it, and also modify other Xen and/or Dom0 command line options you'll make to edit the generated U-Boot script: '''boot.source'''. Look for sched=null in the source and edit as needed. Then you need to regenerate '''boot.scr''' using mkimage:
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<nowiki>
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$ mkimage -A arm64 -T script -C none -a 0xC00000 -e 0xC00000 -d boot.source boot.scr
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</nowiki>
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== U-Boot binaries vs. raw binaries ==
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uboot-script-gen takes only raw binaries as input. If you have a U-Boot binary in your hands and you want to convert it back to a raw binary, you can do that with the following command:
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<nowiki>
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$ dd if=uboot-binary-source of=raw-binary-dest bs=64 skip=1
 
</nowiki>
 
</nowiki>

Revision as of 21:30, 22 October 2019

Booting Xen from U-Boot

Booting Xen from U-Boot requires:

  • loading all the required binaries, manually specifying the loading address for each of them making sure they don't overlap
    • Xen, Dom0 kernel, Dom0 ramdisk, device tree binary, any Dom0-less DomUs kernels, ramdisk and partial dtbs for passthrough
  • adding relevant nodes to device tree
    • the Dom0 kernel and ramdisk loading addresses need to be specified in device tree under /chosen

See booting.txt as a reference.

ImageBuilder

The whole process can be automated with ImageBuilder:

https://gitlab.com/ViryaOS/imagebuilder

ImageBuilder can be invoked as a container for build automation, but its useful scripts can also be called manually. Specifically, script/uboot-script-gen generates a U-Boot script that loads all the necessary binaries and automatically adds the required entries to device tree at boot time. In order to use it, you need to write a config file first.

Config file

MEMORY_START="0x0"
MEMORY_END="0x80000000"

UBOOT_DIR="uboot"

DEVICE_TREE="board.dtb"
XEN="xen-hypervisor"
DOM0_KERNEL="Image-dom0"
DOM0_RAMDISK="ramdisk-dom0.rootfs.cpio.gz"

NUM_DOMUS=2
DOMU_KERNEL[0]="dom1/Image-domU"
DOMU_RAMDISK[0]="dom1/ramdisk-domU"
DOMU_PASSTHROUGH_DTB[0]="dom1/passthrough-domU.dtb"
DOMU_KERNEL[1]="dom2/Image-domU"
DOMU_RAMDISK[1]="dom2/ramdisk-domU2"

UBOOT_SOURCE="boot.source"
UBOOT_SCRIPT="boot.scr"

The fields are self explanatory but you can find more detailed information on the readme. Make sure to use raw binaries for Xen, all the kernels and rootfs's, not U-Boot binaries (do not use the output of mkimage).

uboot-script-gen

Once you have the config file, you can call uboot-script-gen as follows:

$ export LOAD_CMD="tftpb"
$ bash ./scripts/uboot-script-gen /path/to/config

to generate a U-Boot script named *boot.scr* that will load all your binaries automatically using tftp, you just need to load boot.scr and source it.

$ tftpb 0xC00000 boot.scr; source 0xC00000

The command used to load the binaries can be customized, for instance you can have uboot-script-gen generate a U-Boot script that loads binaries from an SD card changing LOAD_CMD to "load scsi 0:1":

$ export LOAD_CMD="load scsi 0:1"
$ bash ./scripts/uboot-script-gen /path/to/config

Important Notes

Xen and Dom0 command line

ImageBuilder uses sched=null by default. If you want to change it, and also modify other Xen and/or Dom0 command line options you'll make to edit the generated U-Boot script: boot.source. Look for sched=null in the source and edit as needed. Then you need to regenerate boot.scr using mkimage:

$ mkimage -A arm64 -T script -C none -a 0xC00000 -e 0xC00000 -d boot.source boot.scr

U-Boot binaries vs. raw binaries

uboot-script-gen takes only raw binaries as input. If you have a U-Boot binary in your hands and you want to convert it back to a raw binary, you can do that with the following command:

$ dd if=uboot-binary-source of=raw-binary-dest bs=64 skip=1