All of lore.kernel.org
 help / color / mirror / Atom feed
From: David Hildenbrand <david@redhat.com>
To: Mike Rapoport <rppt@linux.ibm.com>
Cc: Alex Ghiti <alex@ghiti.fr>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-arch@vger.kernel.org, linux-mm@kvack.org,
	Vitaly Wool <vitaly.wool@konsulko.com>
Subject: Re: [PATCH v7] RISC-V: enable XIP
Date: Fri, 9 Apr 2021 16:16:50 +0200	[thread overview]
Message-ID: <2d442bca-c367-598c-b4ee-746925517118@redhat.com> (raw)
In-Reply-To: <YHBgUs1JKvHWkG9F@linux.ibm.com>

On 09.04.21 16:10, Mike Rapoport wrote:
> On Fri, Apr 09, 2021 at 02:07:24PM +0200, David Hildenbrand wrote:
>> On 09.04.21 13:39, Alex Ghiti wrote:
>>> Hi David,
>>
>> I assume you still somehow create the direct mapping for the kernel, right?
>> So it's really some memory region with a direct mapping but without a memmap
>> (and right now, without a resource), correct?
> 
> XIP kernel text is not a region in memory to begin with ;-)

I think that's the part that confused me. I thought it would be mapped 
somehow into physical address space and would be addressed like other 
memory -- just that reads would be rewired to go to flash.

> 
> It resides in a flash and it is executed directly from there without being
> relocated to RAM.
> 
> That's why it does not need neither direct mapping, nor struct pages.

Thanks for clarifying! :)

-- 
Thanks,

David / dhildenb


WARNING: multiple messages have this Message-ID (diff)
From: David Hildenbrand <david@redhat.com>
To: Mike Rapoport <rppt@linux.ibm.com>
Cc: Alex Ghiti <alex@ghiti.fr>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-arch@vger.kernel.org, linux-mm@kvack.org,
	Vitaly Wool <vitaly.wool@konsulko.com>
Subject: Re: [PATCH v7] RISC-V: enable XIP
Date: Fri, 9 Apr 2021 16:16:50 +0200	[thread overview]
Message-ID: <2d442bca-c367-598c-b4ee-746925517118@redhat.com> (raw)
In-Reply-To: <YHBgUs1JKvHWkG9F@linux.ibm.com>

On 09.04.21 16:10, Mike Rapoport wrote:
> On Fri, Apr 09, 2021 at 02:07:24PM +0200, David Hildenbrand wrote:
>> On 09.04.21 13:39, Alex Ghiti wrote:
>>> Hi David,
>>
>> I assume you still somehow create the direct mapping for the kernel, right?
>> So it's really some memory region with a direct mapping but without a memmap
>> (and right now, without a resource), correct?
> 
> XIP kernel text is not a region in memory to begin with ;-)

I think that's the part that confused me. I thought it would be mapped 
somehow into physical address space and would be addressed like other 
memory -- just that reads would be rewired to go to flash.

> 
> It resides in a flash and it is executed directly from there without being
> relocated to RAM.
> 
> That's why it does not need neither direct mapping, nor struct pages.

Thanks for clarifying! :)

-- 
Thanks,

David / dhildenb


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

  reply	other threads:[~2021-04-09 14:17 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-09  6:51 [PATCH v7] RISC-V: enable XIP Alexandre Ghiti
2021-04-09  6:51 ` Alexandre Ghiti
2021-04-09  7:14 ` Alex Ghiti
2021-04-09  7:14   ` Alex Ghiti
2021-04-09  8:23   ` David Hildenbrand
2021-04-09  8:23     ` David Hildenbrand
2021-04-09 11:39     ` Alex Ghiti
2021-04-09 11:39       ` Alex Ghiti
2021-04-09 12:07       ` David Hildenbrand
2021-04-09 12:07         ` David Hildenbrand
2021-04-09 12:57         ` Alex Ghiti
2021-04-09 12:57           ` Alex Ghiti
2021-04-09 14:10         ` Mike Rapoport
2021-04-09 14:10           ` Mike Rapoport
2021-04-09 14:16           ` David Hildenbrand [this message]
2021-04-09 14:16             ` David Hildenbrand
2021-04-09 12:12       ` Mike Rapoport
2021-04-09 12:12         ` Mike Rapoport
2021-04-09 12:46         ` David Hildenbrand
2021-04-09 12:46           ` David Hildenbrand
2021-04-09 13:59           ` Mike Rapoport
2021-04-09 13:59             ` Mike Rapoport
2021-04-09 14:10             ` David Hildenbrand
2021-04-09 14:10               ` David Hildenbrand
2021-04-09 14:42             ` Vitaly Wool
2021-04-09 14:42               ` Vitaly Wool
2021-04-09 14:42               ` Vitaly Wool
2021-04-12  5:12               ` Alex Ghiti
2021-04-12  5:12                 ` Alex Ghiti
2021-04-12  7:49                 ` Vitaly Wool
2021-04-12  7:49                   ` Vitaly Wool
2021-04-12  7:49                   ` Vitaly Wool

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=2d442bca-c367-598c-b4ee-746925517118@redhat.com \
    --to=david@redhat.com \
    --cc=alex@ghiti.fr \
    --cc=aou@eecs.berkeley.edu \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=palmer@dabbelt.com \
    --cc=paul.walmsley@sifive.com \
    --cc=rppt@linux.ibm.com \
    --cc=vitaly.wool@konsulko.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.