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Message-ID: <4BC4572D.10502@ladisch.de>
Date: Tue, 13 Apr 2010 13:36:13 +0200
From: Clemens Ladisch <clemens@ladisch.de>
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To: Krishna Gopal <linuxkrishna@gmail.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: Accessing peripheral register directly from userspace
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Krishna Gopal wrote:
> Would there be any issues for optimization purpose I do a mmap to a
> peripheral register to directly access it from userspace ?

This means that userspace could access any register in the same page.

Usually this is done only with read-only pages and with devices that
are designed for this so that all accessible registers are 'safe'.


Regards,
Clemens