From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?utf-8?Q?Beno=C3=AEt_Th=C3=A9baudeau?= <benoit.thebaudeau@advansee.com>
Date: Fri, 20 Jul 2012 15:17:38 +0200 (CEST)
Subject: [U-Boot] [PATCH v2 2/5] ehci-hcd: Boost transfer speed
In-Reply-To: <50094301.5010507@herbrechtsmeier.net>
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On Friday 20 July 2012 13:37:37 Stefan Herbrechtsmeier wrote:
> Am 20.07.2012 13:26, schrieb Beno?t Th?baudeau:
> > +			int xfr_bytes = min(left_length,
> > +					    (QT_BUFFER_CNT * 4096 -
> > +					     ((uint32_t)buf_ptr & 4095)) &
> > +					    ~4095);
> Why you align the length to 4096?

It's to guarantee that each transfer length is a multiple of the max packet
length. Otherwise, early short packets are issued, which breaks the transfer and
results in time-out error messages.

Regards,
Beno?t