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From: Stephen Warren <swarren@wwwdotorg.org>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH V2] usb: ci_udc: Allocate the qTD list directly
Date: Tue, 01 Jul 2014 09:03:17 -0600	[thread overview]
Message-ID: <53B2CDB5.5020803@wwwdotorg.org> (raw)
In-Reply-To: <1404173061-6691-1-git-send-email-marex@denx.de>

On 06/30/2014 06:04 PM, Marek Vasut wrote:
> Instead of weird allocation of ci_drv->items_mem and then even weirder
> distribution of offsets in this memory area into ci_drv->items array,
> just allocate ci_drv->items as a big slab of aligned memory (replaces
> ci_drv->items_mem) and let ci_get_qtd() do the distribution of offsets
> in this memory area.

As I mentioned on IRC, this patch isn't correct.

The existing code ensures that each pair of QTDs are correctly aligned,
hence the slight complexity. The new code only actively ensures that the
first QTD is correctly aligned; the subsequent QTDs will only be
correctly aligned if the sizeof the QTD structure is an exact multiple
of the alignment requirements. In practice, it is on my system at least,
but that may not be generally true.

  parent reply	other threads:[~2014-07-01 15:03 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-30 23:53 [U-Boot] [PATCH] usb: ci_udc: Allocate the qTD list directly Marek Vasut
2014-06-30 23:55 ` Marek Vasut
2014-07-01  0:04 ` [U-Boot] [PATCH V2] " Marek Vasut
2014-07-01  6:51   ` Jörg Krause
2014-07-01 10:17     ` Marek Vasut
2014-07-01 11:03       ` Jörg Krause
2014-07-01 11:19         ` Marek Vasut
2014-07-01 11:22           ` Jörg Krause
2014-07-01 11:35             ` Marek Vasut
2014-07-01 11:48               ` Jörg Krause
2014-07-01 22:34             ` Jörg Krause
2014-07-01 22:36               ` Stephen Warren
2014-07-01 22:47                 ` Jörg Krause
2014-07-01 22:51                   ` Stephen Warren
2014-07-01 22:57                     ` Jörg Krause
2014-07-01 23:10                       ` Stephen Warren
2014-07-01 15:03   ` Stephen Warren [this message]
2014-07-01 15:13     ` Marek Vasut
2014-07-01 15:16       ` Stephen Warren
2014-07-01 15:22         ` Marek Vasut

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