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Subject: Re: [PATCH 12/37] atl1c: restore max-read-request-size in Device
 Conrol Register
From: Ben Hutchings <bhutchings@solarflare.com>
To: xiong <xiong@qca.qualcomm.com>
CC: <davem@davemloft.net>, <netdev@vger.kernel.org>,
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Date: Fri, 13 Apr 2012 18:02:43 +0100
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	 <1334276102-15866-13-git-send-email-xiong@qca.qualcomm.com>
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On Fri, 2012-04-13 at 08:14 +0800, xiong wrote:
> in some platforms, we found the max-read-request-size in Device Control
> Register is set to 0 by (BIOS?) during bootup, this will cause the
> performance(throughput) very bad.
> Restore it to a min-value.
> register definition of REG_DEVICE_CTRL is refined as well.
[...]

I'm guessing this memory-mapped register is an alias for the PCIe device
control register.  I think you should be using pcie_set_readrq() to
ensure that the final setting conforms to the device's Max Payload Size
and system policy.

Ben.

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