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References: <20230103164359.24347-1-ysionneau@kalray.eu> <20230103164359.24347-2-ysionneau@kalray.eu>
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From:   Jeff Xie <xiehuan09@gmail.com>
Date:   Wed, 18 Jan 2023 23:09:45 +0800
Message-ID: <CAEr6+ED_QVYXeu4nMwtr84K_rueEiz_wEufWt3F=xPt7Q043wQ@mail.gmail.com>
Subject: Re: [RFC PATCH 01/25] Documentation: kvx: Add basic documentation
To:     Yann Sionneau <ysionneau@kalray.eu>
Cc:     Jonathan Corbet <corbet@lwn.net>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Clement Leger <clement.leger@bootlin.com>,
        Guillaume Thouvenin <gthouvenin@kalray.eu>
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On Wed, Jan 4, 2023 at 1:04 AM Yann Sionneau <ysionneau@kalray.eu> wrote:
>
> Add some documentation for kvx arch and its Linux port.
>
> CC: Jonathan Corbet <corbet@lwn.net>
> CC: linux-doc@vger.kernel.org
> CC: linux-kernel@vger.kernel.org
> Co-developed-by: Clement Leger <clement.leger@bootlin.com>
> Signed-off-by: Clement Leger <clement.leger@bootlin.com>
> Co-developed-by: Guillaume Thouvenin <gthouvenin@kalray.eu>
> Signed-off-by: Guillaume Thouvenin <gthouvenin@kalray.eu>
> Signed-off-by: Yann Sionneau <ysionneau@kalray.eu>
> ---
>  Documentation/kvx/kvx-exceptions.txt | 246 ++++++++++++++++++++++++
>  Documentation/kvx/kvx-iommu.txt      | 183 ++++++++++++++++++
>  Documentation/kvx/kvx-mmu.txt        | 272 +++++++++++++++++++++++++++
>  Documentation/kvx/kvx-smp.txt        |  36 ++++
>  Documentation/kvx/kvx.txt            | 268 ++++++++++++++++++++++++++
>  5 files changed, 1005 insertions(+)
>  create mode 100644 Documentation/kvx/kvx-exceptions.txt
>  create mode 100644 Documentation/kvx/kvx-iommu.txt
>  create mode 100644 Documentation/kvx/kvx-mmu.txt
>  create mode 100644 Documentation/kvx/kvx-smp.txt
>  create mode 100644 Documentation/kvx/kvx.txt

[...]

> +Virtual and physical memory
> +===========================
> +
> +The mapping used and the memory management is described in
> +Documentation/kvx/kvx-mmu.txt.
> +Our Kernel is compiled using virtual addresses that starts at
> +0xffffff0000000000. But when it is started the kernel uses physical addresses.
> +Before calling the first function arch_low_level_start() we configure 2 entries
> +of the LTLB.
> +
> +The first entry will map the first 1G of virtual address space to the first
> +1G of DDR:
> +  - TLB[0]: 0xffffff0000000000 -> 0x100000000 (size 512Mo)

Maybe should change it to:
 - TLB[0]: 0xffffff8000000000 -> 0x100000000 (size 512Mo)

As the PAGE_OFFSET = 0xffffff8000000000

[...]


-- 
Thanks,
JeffXie