Date: Tue, 28 Apr 2015 11:28:53 -0400 (EDT)
From: Nicolas Pitre <nicolas.pitre@linaro.org>
To: Russell King - ARM Linux <linux@arm.linux.org.uk>
cc: Geert Uytterhoeven <geert@linux-m68k.org>,
        Tomi Valkeinen <tomi.valkeinen@ti.com>, Pavel Machek <pavel@ucw.cz>,
        Archit Taneja <architt@codeaurora.org>,
        Marek Vasut <marek.vasut@gmail.com>,
        kernel list <linux-kernel@vger.kernel.org>,
        Dinh Nguyen <dinh.linux@gmail.com>,
        Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>,
        Grant Likely <grant.likely@linaro.org>,
        Rob Herring <robh+dt@kernel.org>, Jingoo Han <jg1.han@samsung.com>,
        Rob Clark <robdclark@gmail.com>,
        Linux Fbdev development list <linux-fbdev@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        Alexander Shiyan <shc_work@mail.ru>,
        H Hartley Sweeten <hsweeten@visionengravers.com>
Subject: Re: simple framebuffer slower by factor of 20, on socfpga (arm)
 platform
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On Tue, 28 Apr 2015, Russell King - ARM Linux wrote:

> On Fri, Apr 24, 2015 at 03:46:56PM +0200, Geert Uytterhoeven wrote:
> > So please optimize ARM's _memcpy_fromio(), _memcpy_toio(), and _memset_io().
> > That will benefit other drivers on ARM, too.
> 
> That's not going to happen.
> 
> I've had a patch which does that, but people are concerned that it changes
> the behaviour of the functions by changing the access size, which could
> cause regressions.  It seems people are far too worried about that to even
> consider trying. :(

What about making the optimized implementation available via kconfig?


Nicolas
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