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From: "lovecentry" <lovecentry@gmail.com>
To: <linux-mips@linux-mips.org>
Subject: kseg1 uncache access issue
Date: Wed, 9 Jan 2008 00:35:06 +0800	[thread overview]
Message-ID: <4783a652.1cef600a.2530.fffffe31@mx.google.com> (raw)

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Hi

As we know in mips achitecture if current pc falls into kseg1 segment, any
memory reference will bypass cache and fetch directly from dram. But for
some prcoessor such like mips R10K it has off chip L2 cache. I haven't found
any available path which can access dram directly. All memory reference need
pass through L2 cache. Does it mean any memory reference in kseg1 will be
fetch from L2 cache rather than dram for such system? How does such system
design when system software need access kseg1 region? Further more, Kseg2 is
used to do memory map for those peripheral so Is there has a particular
circuit that routes those access to the appropriate destination.

Any suggestion is highly appreciate!!!

 

Tony


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WARNING: multiple messages have this Message-ID (diff)
From: "lovecentry" <lovecentry@gmail.com>
To: linux-mips@linux-mips.org
Subject: kseg1 uncache access issue
Date: Wed, 9 Jan 2008 00:35:06 +0800	[thread overview]
Message-ID: <4783a652.1cef600a.2530.fffffe31@mx.google.com> (raw)
Message-ID: <20080108163506.Q3Uxt8afbtK6WJ8MdpGXf5h3br5wNjmyhRptnn-8p3w@z> (raw)

[-- Attachment #1: Type: text/plain, Size: 719 bytes --]

Hi

As we know in mips achitecture if current pc falls into kseg1 segment, any
memory reference will bypass cache and fetch directly from dram. But for
some prcoessor such like mips R10K it has off chip L2 cache. I haven't found
any available path which can access dram directly. All memory reference need
pass through L2 cache. Does it mean any memory reference in kseg1 will be
fetch from L2 cache rather than dram for such system? How does such system
design when system software need access kseg1 region? Further more, Kseg2 is
used to do memory map for those peripheral so Is there has a particular
circuit that routes those access to the appropriate destination.

Any suggestion is highly appreciate!!!

 

Tony


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             reply	other threads:[~2008-01-08 16:35 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-08 16:35 lovecentry [this message]
2008-01-08 16:35 ` kseg1 uncache access issue lovecentry
2008-01-08 17:02 ` Thomas Bogendoerfer
2008-01-08 18:59   ` Ralf Baechle
2008-01-09 13:20     ` 答复: " lovecentry
2008-01-09 13:20       ` lovecentry

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