From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx3.redhat.com (mx3.redhat.com [172.16.48.32]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id mAG7USY4006121 for ; Sun, 16 Nov 2008 02:30:28 -0500 Received: from oceanus.site5.com (oceanus.site5.com [67.43.13.2]) by mx3.redhat.com (8.13.8/8.13.8) with ESMTP id mAG7UAmc017607 for ; Sun, 16 Nov 2008 02:30:10 -0500 Message-ID: <491FCBFF.9060208@compulab.co.il> Date: Sun, 16 Nov 2008 09:30:07 +0200 From: Mike Rapoport MIME-Version: 1.0 To: Robert Jarzmik References: <87prl4x28e.fsf@free.fr> <491C002F.4070804@compulab.co.il> <87ljvktqtv.fsf@free.fr> In-Reply-To: <87ljvktqtv.fsf@free.fr> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: video4linux-list@redhat.com Subject: Re: pxa_camera: DMA alignment requirement List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: video4linux-list-bounces@redhat.com Errors-To: video4linux-list-bounces@redhat.com List-ID: Robert Jarzmik wrote: > Mike Rapoport writes: > >> Robert Jarzmik wrote: >>> Hello, >>> >>> In the pxa camera driver, the 3 DMA channels used are MMU page aligned. Does >>> somebody remember where that constraint comes from ? >>> >> As far as I remember, the buffers should be page aligned to allow overlaying of >> captured data. > Ah, so that's it, thanks. > >>>From what I read on the PXA manual, the only constraint is 16bytes > alignement. Would you also remember who wrote the code, so that I can ask him > where he read about page alignement constraint please ? Just by coincidence it was me :) I used pxafb_overlay from [1], and my (mis)understanding of what it does added the page alignment constrain. Now looking at the overlay code once more, I'm not sure if it's necessary. --- [1] http://www.rpsys.net/openzaurus/patches/archive/pxa27x_overlay-r8.patch > Cheers. > > -- > Robert > -- Sincerely yours, Mike. -- video4linux-list mailing list Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe https://www.redhat.com/mailman/listinfo/video4linux-list