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							|  |  |  |    Copyright (c) 2020, Linaro
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							|  |  |  | Guest Loader
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							|  |  |  | ------------
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										 |  |  | The guest loader is similar to the ``generic-loader`` although it is
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										 |  |  | aimed at a particular use case of loading hypervisor guests. This is
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							|  |  |  | useful for debugging hypervisors without having to jump through the
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							|  |  |  | hoops of firmware and boot-loaders.
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							|  |  |  | The guest loader does two things:
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							|  |  |  |   - load blobs (kernels and initial ram disks) into memory
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							|  |  |  |   - sets platform FDT data so hypervisors can find and boot them
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										 |  |  | This is what is typically done by a boot-loader like grub using its
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										 |  |  | multi-boot capability. A typical example would look like:
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							|  |  |  | .. parsed-literal::
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							|  |  |  |   |qemu_system| -kernel ~/xen.git/xen/xen \
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							|  |  |  |     -append "dom0_mem=1G,max:1G loglvl=all guest_loglvl=all" \
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							|  |  |  |     -device guest-loader,addr=0x42000000,kernel=Image,bootargs="root=/dev/sda2 ro console=hvc0 earlyprintk=xen" \
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							|  |  |  |     -device guest-loader,addr=0x47000000,initrd=rootfs.cpio
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							|  |  |  | In the above example the Xen hypervisor is loaded by the -kernel
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										 |  |  | parameter and passed its boot arguments via -append. The Dom0 guest
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										 |  |  | is loaded into the areas of memory. Each blob will get
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										 |  |  | ``/chosen/module@<addr>`` entry in the FDT to indicate its location and
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										 |  |  | size. Additional information can be passed with by using additional
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							|  |  |  | arguments.
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							|  |  |  | Currently the only supported machines which use FDT data to boot are
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										 |  |  | the ARM and RiscV ``virt`` machines.
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							|  |  |  | Arguments
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							|  |  |  | ^^^^^^^^^
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							|  |  |  | The full syntax of the guest-loader is::
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							|  |  |  |   -device guest-loader,addr=<addr>[,kernel=<file>,[bootargs=<args>]][,initrd=<file>]
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							|  |  |  | ``addr=<addr>``
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							|  |  |  |   This is mandatory and indicates the start address of the blob.
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							|  |  |  | ``kernel|initrd=<file>``
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							|  |  |  |   Indicates the filename of the kernel or initrd blob. Both blobs will
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							|  |  |  |   have the "multiboot,module" compatibility string as well as
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							|  |  |  |   "multiboot,kernel" or "multiboot,ramdisk" as appropriate.
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							|  |  |  | ``bootargs=<args>``
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							|  |  |  |   This is an optional field for kernel blobs which will pass command
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										 |  |  |   like via the ``/chosen/module@<addr>/bootargs`` node.
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