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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Mon, 20 Jul 2020 14:20:46 +0200
Message-ID: <CAK8P3a2=qrp6x4yLUXhQU2MwcMa4HpEzAdVs_zW8f14GZ-_zqQ@mail.gmail.com>
Subject: Re: [PATCH 3/5] MIPS: Loongson64: Enlarge IO_SPACE_LIMIT
To:     Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc:     "open list:BROADCOM NVRAM DRIVER" <linux-mips@vger.kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Huacai Chen <chenhc@lemote.com>,
        Frank Rowand <frowand.list@gmail.com>,
        Paul Burton <paulburton@kernel.org>,
        Nathan Chancellor <natechancellor@gmail.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        DTML <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Mon, Jul 20, 2020 at 2:07 PM Jiaxun Yang <jiaxun.yang@flygoat.com> wrote:
> 在 2020/7/20 下午6:45, Arnd Bergmann 写道:
> > On Mon, Jul 20, 2020 at 9:44 AM Jiaxun Yang <jiaxun.yang@flygoat.com> wrote:
> >> It can be very big on LS7A PCH systems.
> > In practice, one should rarely need more than a few kb worth of
> > port numbers, unless you expect to see hundreds of legacy PCI
> > devices.
> I must blame stupid hardware design here. The LPC Controller (for ISA
> device) can eat
> up to 0x20000 IO BAR, and we can't resize it. Thus we have to enlarge
> the I/O Space.

Ok, I see.

       Arnd