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Subject: Re: [v2 PATCH] RISC-V: Add a PE/COFF compliant Image header.
To:     Paul Walmsley <paul.walmsley@sifive.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "mark.rutland@arm.com" <mark.rutland@arm.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Anup Patel <anup@brainfault.org>,
        Palmer Dabbelt <palmer@sifive.com>,
        Zong Li <zong@andestech.com>,
        "merker@debian.org" <merker@debian.org>,
        "linux-riscv@lists.infradead.org" <linux-riscv@lists.infradead.org>
References: <20190501195607.32553-1-atish.patra@wdc.com>
 <alpine.DEB.2.21.9999.1905171017510.9104@viisi.sifive.com>
From:   Atish Patra <atish.patra@wdc.com>
Message-ID: <e71f11f1-4c48-342c-a718-de5f14de4c36@wdc.com>
Date:   Fri, 17 May 2019 12:00:22 -0700
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On 5/17/19 10:39 AM, Paul Walmsley wrote:
> 
> 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.
> 
> One other thought: as I think you or someone else may have pointed out,
> this isn't the PE/COFF header itself, but rather an ersatz DOS stub
> header, that is apparently quite close to what some EFI bootloaders
> require.  So from that point of view, it's probably best to just write in
> the patch description that the idea is to add something that resembles an
> MS-DOS stub header, and that the motivations are that:
> 
> 1. it resembles what ARM64 is doing, and there's not much point in
> inventing another boot header format that's completely different
> 

Yup. I will add this in the next version.

> 2. it can be easily converted into an MS-DOS header that some EFI
> bootloaders apparently require, by tweaking a few bytes at the beginning
> 

I mentioned all the required changes in the proposed header to so that 
EFI bootloaders can load it directly. Probably, I will clarify it more 
to avoid confusion.


> 
> - Paul
> 


-- 
Regards,
Atish