From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752672AbXIADCn (ORCPT ); Fri, 31 Aug 2007 23:02:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751552AbXIADCe (ORCPT ); Fri, 31 Aug 2007 23:02:34 -0400 Received: from smtp.gentoo.org ([140.211.166.183]:57365 "EHLO smtp.gentoo.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751511AbXIADCd (ORCPT ); Fri, 31 Aug 2007 23:02:33 -0400 From: Mike Frysinger Organization: wh0rd.org To: linuxsh-dev@lists.sourceforge.net Subject: Re: [PATCH] Patch pvr2 driver to allow development of maple bus driver Date: Fri, 31 Aug 2007 23:02:45 -0400 User-Agent: KMail/1.9.7 Cc: "Adrian McMenamin" , "Mike Frysinger" , Paul Mundt , linux-kernel@vger.kernel.org References: <8b67d60708311300k3ea67eadod531752cca253bbc@mail.gmail.com> <8bd0f97a0708311312n78f1c163o20aa17214bfe3702@mail.gmail.com> <8b67d60708311314p39c7be30v630e97189d656abf@mail.gmail.com> In-Reply-To: <8b67d60708311314p39c7be30v630e97189d656abf@mail.gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart2842700.tRFiO0C76J"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200708312302.46542.vapier@gentoo.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --nextPart2842700.tRFiO0C76J Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On Friday 31 August 2007, Adrian McMenamin wrote: > On 31/08/2007, Mike Frysinger wrote: > > On 8/31/07, Adrian McMenamin wrote: > > > This patch makes the PVR2 VBLANK interrupt on the SEGA Dreamcast > > > shareable - a small but necessary change to enable ongoing efforts to > > > develop a driver for the maple bus on the Dreamcast. (Maple is Sega's > > > proprietary serial interface for the Dreamcast and can be set to > > > synchronise dma transfers to the VBLANK). > > > > > > This has no impact on the performance of the PVR2. > > > > sharable implies the interrupt handler checks to see if it actually > > caused the interrupt ... which it doesnt at the moment ... presumably, > > you're making it shared because another device will be using that > > interrupt as well ... so when that other device gets an interrupt, how > > do you know it's for that device and not PVR2 ? > > If the interrupt occurs then it will be for both of them. The hardware > cannot be removed and the maple bus driver is set for hardware sync. > > The question seems redundant to me. i really dont know how the maple bus works or what piece of hardware is wir= ed=20 up to the same interrupt line. my point is that if the other device fires = an=20 interrupt, the pvr interrupt handler may be executed and attempt to do work= =20 when in reality the pvr was not the source of the interrupt. =2Dmike --nextPart2842700.tRFiO0C76J Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.6 (GNU/Linux) iQIVAwUARtjWVkFjO5/oN/WBAQIEihAAwyLXm7hCbKiuCpwU7iNYURfWp925lzni q1iVZvZ2wHwTTlGfdwdcj5JqNq+jNLo4FYhKaHNj3MSOfMCPbsj0M0Ehv/OIkar3 lahqKE0U+W89OATfdMTxSpSUdn+gSv/8Kk8QipOYW6wB2zfy7xDHCYVN4K62WqFp EThjI5t04drP064RdJfyV1m1BM95OS33+QHpeGBtFsjp2yRdKFcfkblYvk15rD6V hszT4h0sqz70Q8xfcqdXYYrTUJpOMr0Cw9pb4EO8nwpKDlpA0F1EWcDpMwDgJILF X234btTxtPf5hZ0HFfvXUvvO4cpoFRnYvErGGObirxQqSPgmADQ2rqXhw5KqxQ8K megksKI4DuehAeLXEFDP9YGX23hBBPSrFV4TL4Qj+A5QcsN18LNaK26eOBlHAss3 yg/HwbpL2fb8CNu0K0HvOOez4R2Egxwy2GeUYzPageyaQalODlfvKz56lpOeSy/v dMepbhuAWxm4GM6YQoP/9hItqFQv/vSZdmZv24iEzAm2qwUY1x2OUx68esRdKGbn +F+zAV5HYFHLj3HHe2zvOFlr+7ocdPypRlnqmSW+xXoWWTMW43jesQUYP3Fwlhmx LtkCgM+xFUclRWWzq5r8Vzo4WRcCUUYIkdGtyARf1kRQ5NLHUk1oU/kFJUaXUNRw MRamIjVzobA= =80Nh -----END PGP SIGNATURE----- --nextPart2842700.tRFiO0C76J--