From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Kleine-Budde Subject: Re: [PATCH net-next-2.6 v3] can: Topcliff: PCH_CAN driver: Add Flow control, Date: Mon, 22 Nov 2010 09:27:50 +0100 Message-ID: <4CEA2986.4080607@pengutronix.de> References: <4CE2434B.5050701@dsn.okisemi.com> <4CE27796.2000206@pengutronix.de> <007401cb87b1$a773b3d0$66f8800a@maildom.okisemi.com> <4CE64167.2030405@pengutronix.de> <003201cb8a02$f05b15e0$66f8800a@maildom.okisemi.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============9021791802722147259==" Cc: andrew.chih.howe.khor-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, Masayuki Ohtake , Samuel Ortiz , margie.foster-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, yong.y.wang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, socketcan-core-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org, kok.howg.ewe-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, joel.clark-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, qi.wang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, "David S. Miller" , Christian Pellegrin , Wolfgang Grandegger To: Tomoya MORINAGA Return-path: In-Reply-To: <003201cb8a02$f05b15e0$66f8800a-a06+6cuVnkTSQfdrb5gaxUEOCMrvLtNR@public.gmane.org> 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 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --===============9021791802722147259== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig6AB79154414CF0941E795E6A" This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig6AB79154414CF0941E795E6A Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 11/22/2010 06:05 AM, Tomoya MORINAGA wrote: > On Friday, November 19, 2010 6:20 PM, Marc Kleine-Budde wrote : >=20 >>>>> - spin_unlock_irqrestore(&priv->msgif_reg_lock, flags); >>>>> + pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no); >>>> Still we have the busy waiting in the TX path. Maybe you can move th= e >>>> waiting before accessing the if[1] and remove the busy waiting here.= >>> I can't understand your saying. >>> For transmitting data, calling pch_can_rw_msg_obj is mandatory. >> Yes, but the busy wait is not needed. It should be enough to do the >> busy-waiting _before_ accessing the if[1]. >=20 > Do you mean we should create other pch_can_rw_msg_obj which doesn't hav= e busy wait ? ACK, and this non busy waiting is use in the TX path. But you add a busy wait only function before accessing the if[1] in the TX path. cheers, Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de | --------------enig6AB79154414CF0941E795E6A Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkzqKYoACgkQjTAFq1RaXHOeXQCfT7VKvE6KPYvx51UzDh+mMJzd hD8An2psKQO3bRnvocjSPOu3zAqs8Blw =4RUa -----END PGP SIGNATURE----- --------------enig6AB79154414CF0941E795E6A-- --===============9021791802722147259== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Socketcan-core mailing list Socketcan-core-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org https://lists.berlios.de/mailman/listinfo/socketcan-core --===============9021791802722147259==--