From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Tomoya MORINAGA" Subject: Re: [PATCH net-next-2.6 v2] can: Topcliff: PCH_CAN driver: Fix build warnings Date: Mon, 1 Nov 2010 16:15:01 +0900 Message-ID: <002701cb7994$81db1350$66f8800a@maildom.okisemi.com> References: <4CCAA3D4.8070408@dsn.okisemi.com> <4CCAC4CD.7000503@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: andrew.chih.howe.khor-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, Masayuki Ohtake , Samuel Ortiz , margie.foster-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, socketcan-core-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org, yong.y.wang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, kok.howg.ewe-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, Wolfgang Grandegger , joel.clark-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, "David S. Miller" , Christian Pellegrin , qi.wang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org To: "Marc Kleine-Budde" Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: socketcan-core-bounces-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org Errors-To: socketcan-core-bounces-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org List-Id: netdev.vger.kernel.org On Friday, October 29, 2010 9:57 PM : Marc Kleine-Budde wrote: >>>> SW must check busy flag of CAN register. >>>> This is a Topcliff HW specification. >>> Maybe the busy check could also be done *before* the Message RAM is >>> accessed to avoid (or minimize) waiting. >> Yes, *before* is right. >> If there is *after* processing, this is a bug. >> Can you see anyway ? >Sorry I don't understand what you mean. Sorry, my English had mistake. I show my comment below again. - If there is *after* processing, this is a bug. - Can you see the point anywhere ? > You probably know the datasheet, but I don't, although I've printed > chapter 13 from the Intel Controller Hub EG20T datasheet, but it's 50+ > pages. If the hardware needs the busy waiting in the hot tx path a > pointer to the respective section in the manual is a good idea. Just > something like: Though "Oliver Hartkopp" found the place of Datasheet EG20T and notified with the mailing-list, Have you read the following ? http://edc.intel.com/Platforms/Atom-E6xx/#hardware >>> You have to change the definition of the regs struct a bit: >>>> u32 if1_mcont; >>>> u32 if1_data[4]; >>>> u32 reserve2; >> Uh, I can't find this. Where is this ? >Here's a patch to illustrate what I meant: I understand. Thanks, Tomoya(OKI SEMICONDUCTOR CO., LTD.)