From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anatolij Gustschin Date: Thu, 24 May 2012 08:57:24 +0200 Subject: [U-Boot] [PATCH 3/4 V2] USB: Drop cache flush bloat in EHCI-HCD In-Reply-To: <1333946851-27904-1-git-send-email-marex@denx.de> References: <1333940992-15484-4-git-send-email-marex@denx.de> <1333946851-27904-1-git-send-email-marex@denx.de> Message-ID: <20120524085724.3f2e50c0@wker> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Marek, On Mon, 9 Apr 2012 06:47:31 +0200 Marek Vasut wrote: > Discard the creepy cache flushing mechanisms in ehci-hcd.c and replace them with > more straightforward flushing. In the new approach, the flushing takes place > directly in ehci_submit_async() call instead of going through the QH list and > flushing all members and buffers. This discards a lot of weird bit operations > on the members of QH and qTD structures. > > NOTE: Certainly, this flushes even qTDs which are possibly unused in some > transactions, though the overhead of the previous code was much higher than is > the overhead of flushing two more cache lines (which most probably aren't even > cached). > > Signed-off-by: Marek Vasut > Cc: Puneet Saxena > --- > drivers/usb/host/ehci-hcd.c | 127 +++++++++---------------------------------- > 1 files changed, 27 insertions(+), 100 deletions(-) Unfortunately this patch breaks compiling for many powerpc boards, mpc512x, mpc83xx, mpc85xx and QorIQ Px based with USB support enabled. Thanks, Anatolij