From: Paul Walmsley <paul.walmsley@sifive.com>
To: Atish Patra <atish.patra@wdc.com>
Cc: mark.rutland@arm.com, Albert Ou <aou@eecs.berkeley.edu>,
Anup Patel <anup@brainfault.org>,
Palmer Dabbelt <palmer@sifive.com>,
linux-kernel@vger.kernel.org, Zong Li <zong@andestech.com>,
merker@debian.org, linux-riscv@lists.infradead.org
Subject: Re: [v2 PATCH] RISC-V: Add a PE/COFF compliant Image header.
Date: Mon, 13 May 2019 15:31:16 -0700 (PDT) [thread overview]
Message-ID: <alpine.DEB.2.21.9999.1905131522370.21198@viisi.sifive.com> (raw)
In-Reply-To: <20190501195607.32553-1-atish.patra@wdc.com>
On Wed, 1 May 2019, Atish Patra wrote:
> Currently, last stage boot loaders such as U-Boot can accept only
> uImage which is an unnecessary additional step in automating boot flows.
>
> Add a PE/COFF compliant image header that boot loaders can parse and
> directly load kernel flat Image. The existing booting methods will continue
> to work as it is.
>
> Another goal of this header is to support EFI stub for RISC-V in future.
> EFI specification needs PE/COFF image header in the beginning of the kernel
> image in order to load it as an EFI application. In order to support
> EFI stub, code0 should be replaced with "MZ" magic string and res5(at
> offset 0x3c) should point to the rest of the PE/COFF header (which will
> be added during EFI support).
>
> Tested on both QEMU and HiFive Unleashed using OpenSBI + U-Boot + Linux.
>
> Signed-off-by: Atish Patra <atish.patra@wdc.com>
Seems like we're stuck with this basic format for EFI, etc. Even though
we may be stuck with it, I think we should take the opportunity to add the
possibility to extending this header format by adding fields after the
basic PE/COFF header ends.
In particular, at the very least, I'd suggest adding a u32 after the
PE/COFF header ends, to represent a "RISC-V header format version number".
Then if we add more fields that follow the PE/COFF header -- for example,
to represent the RISC-V instruction set extensions that are required to
run this binary -- we can just bump that RISC-V-specific version number
field to indicate to bootloaders that there's more there.
One other observation - if what's here was copied from some other
architecture, like ARM, please acknowledge the source in the patch
description.
thanks
- Paul
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
next prev parent reply other threads:[~2019-05-13 22:31 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-01 19:56 [v2 PATCH] RISC-V: Add a PE/COFF compliant Image header Atish Patra
2019-05-05 0:37 ` Karsten Merker
2019-05-11 20:57 ` Karsten Merker
2019-05-13 22:31 ` Paul Walmsley [this message]
2019-05-13 23:18 ` Atish Patra
2019-05-14 0:09 ` Paul Walmsley
2019-05-14 0:34 ` Atish Patra
2019-05-14 0:39 ` Paul Walmsley
2019-05-14 1:13 ` Atish Patra
2019-05-16 16:20 ` Paul Walmsley
2019-05-23 18:35 ` Atish Patra
2019-05-23 18:45 ` Paul Walmsley
2019-05-17 17:39 ` Paul Walmsley
2019-05-17 19:00 ` Atish Patra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.DEB.2.21.9999.1905131522370.21198@viisi.sifive.com \
--to=paul.walmsley@sifive.com \
--cc=anup@brainfault.org \
--cc=aou@eecs.berkeley.edu \
--cc=atish.patra@wdc.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=mark.rutland@arm.com \
--cc=merker@debian.org \
--cc=palmer@sifive.com \
--cc=zong@andestech.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).