Re: [PATCH v5] USB: ehci-pci: USB host controller support for Intel Quark X1000

From: Greg Kroah-Hartman
Date: Wed Jul 09 2014 - 19:03:28 EST

On Wed, Jul 02, 2014 at 01:58:18AM -0700, Chen, Alvin wrote:
> From: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxx>
> The EHCI packet buffer in/out threshold is programmable for Intel Quark X1000
> USB host controller, and the default value is 0x20 dwords. The in/out threshold
> can be programmed to 0x80 dwords (512 Bytes) to maximize the perfomrance,
> but only when isochronous/interrupt transactions are not initiated by the USB
> host controller. This patch is to reconfigure the packet buffer in/out
> threshold as maximal as possible to maximize the performance, and 0x7F dwords
> (508 Bytes) should be used because the USB host controller initiates
> isochronous/interrupt transactions.
> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxx>
> Signed-off-by: Alvin (Weike) Chen <alvin.chen@xxxxxxxxx>
> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> Reviewed-by: Jingoo Han <jg1.han@xxxxxxxxxxx>
> ---
> Changlog v5:
> * Correct the wrong comment style.
> drivers/usb/host/ehci-pci.c | 25 +++++++++++++++++++++++++
> 1 file changed, 25 insertions(+)

This should go to stable kernel releases as well, right?


greg k-h
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