Hi,
On 27/03/20 6:43 pm, Peng Fan wrote:
Hi Angelo,
Subject: [RFC] Linux-less boot
Hi Jan, Peng, all,
We currently have a better understanding of Peng's work [1] and manage to
somewhat reproduce his results on another NXP board, the IMX8QM.
Good.
Since you showed interest in this, we would like to start implement something
a bit more portable and user-friendly.
In this regard, I would like to share some design choices:
- Jailhouse image stays more or less the same, all the code is added into a
loader, expanding Peng's work to make it more portable (across Arm v8
boards for now) and generic. The loader will boot and init everything that
jailhouse and the inmates need. Without the loader jailhouse can be started
exactly like it was before.
- The loader is platform-specific, and thus it's necessary, at compile-time, to
have a parameter that specifies the target (something like `BOOT=` or
`TARGET=`), using the root-cell information to fill the correct addresses and
compile only the necessary drivers. Without the parameter, the loader is not
compiled.
I am not sure about x86. But for AARCH64 and RISC, let uboot pass
a table to the loader, the table contains all platform specific things. The
format
should be defined by jailhouse community.
I had tried to prototype the type1 jailhouse bootloader long time back. [1]
I used a python script [2] to describe all the images needed for
loading the different cells.
It might be different files for Linux, baremetal inmates, etc
Based on the arguments, python script generates a data structure [3]
which loader can understand.
I also generated a linker script which packaged all the binaries in
single elf. But that can be ignored.
[1]
https://github.com/nikhildevshatwar/jailhouse/commit/6883c0a0b1e4cd12e8097cb656262f6d9b2fb4b1
[2]
https://github.com/nikhildevshatwar/jailhouse/blob/devel/type1-poc-upstream/tools/jailhouse-loader.py
[3]
https://github.com/nikhildevshatwar/jailhouse/blob/devel/type1-poc-upstream/loader.h
Regards,
Nikhil D
Or use device tree, but that means needs to import libfdt to jailhouse.
- There is going to be a "sync" function at some point, probably when loading
the module, that can update the status of jailhouse so that the cells created at
boot time are controllable. The idea is to have the same situation as if
jailhouse was started with the `enable`.
Agree.
Finally, we would also like to hear from Peng, to understand his current plan
so that we don't step in each other's toes.
Ah. I was crazy busy in the past days on some remoteproc work, so stop the
Loader work for a while. but the other work will be done in a few days, and
I will back to this:)
Actually this feature is planned in our software release, and I need to have
the loader related stuff checked in NXP tree in the end of April.
My planned stuff are:
arm32+arm64 inmate cell with arm64 jailhouse.
Real cache color with Linux root cell + one inmate cell, and considering fit
jailhouse into SRAM.
As you listed, userspace tool support.
Considering MMU for loader. But not sure this really needed currently.
It is good we could reuse the work between, but not sure I could wait
until then, because I have a tight schedule.
Thanks,
Peng.
[1]
https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgroups
.google.com%2Fforum%2F%23!topic%2Fjailhouse-dev%2FIZEFz-e2lh4&d
ata=02%7C01%7Cpeng.fan%40nxp.com%7C8ae0f1ab40054707b2af08d7d24
3be6f%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6372090607
11306332&sdata=r8uxIgLOTqIMydWTlo6rDdaerSPd12MRnURPIUDA9X0
%3D&reserved=0
Angelo
--
You received this message because you are subscribed to the Google Groups
"Jailhouse" group.
To unsubscribe from this group and stop receiving emails from it, send an
email to [email protected].
To view this discussion on the web visit
https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgroups
.google.com%2Fd%2Fmsgid%2Fjailhouse-dev%2FCADiTV-1QiRhSWZnw%252
BkHhJMO-BoA4sAcOmTkQE7ZWbHkGh3Jexw%2540mail.gmail.com&dat
a=02%7C01%7Cpeng.fan%40nxp.com%7C8ae0f1ab40054707b2af08d7d243b
e6f%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637209060711
306332&sdata=L4PCq2Lo6FlAqzw%2FhPr0p7dhtG3DrOsfRl%2BBtBV7lA
w%3D&reserved=0.
--
You received this message because you are subscribed to the Google Groups
"Jailhouse" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion on the web visit
https://groups.google.com/d/msgid/jailhouse-dev/964aced1-3e41-f9fc-30b7-57c7044acda2%40ti.com.
