From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6EAEAC433E6 for ; Wed, 3 Feb 2021 08:13:39 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0947D64F50 for ; Wed, 3 Feb 2021 08:13:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0947D64F50 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=thesusis.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 37D656E9D3; Wed, 3 Feb 2021 08:13:08 +0000 (UTC) Received: from vps.thesusis.net (vps.thesusis.net [34.202.238.73]) by gabe.freedesktop.org (Postfix) with ESMTPS id CBC8F6E923 for ; Tue, 2 Feb 2021 15:15:56 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by vps.thesusis.net (Postfix) with ESMTP id DFE99243CA; Tue, 2 Feb 2021 10:15:55 -0500 (EST) Received: from vps.thesusis.net ([127.0.0.1]) by localhost (vps.thesusis.net [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id F7YuhNWjVJSq; Tue, 2 Feb 2021 10:15:55 -0500 (EST) Received: by vps.thesusis.net (Postfix, from userid 1000) id A3BDC243C7; Tue, 2 Feb 2021 10:15:55 -0500 (EST) References: <20200916205434.GA10389@duo.ucw.cz> <87czyf5jjp.fsf@vps.thesusis.net> <87k0s4ai33.fsf@vps.thesusis.net> User-agent: mu4e 1.5.7; emacs 26.3 From: Phillip Susi To: Daniel Vetter Subject: Re: fbcon: remove soft scrollback code (missing Doc. patch) Date: Tue, 02 Feb 2021 10:13:14 -0500 In-reply-to: Message-ID: <87wnvqts9g.fsf@vps.thesusis.net> MIME-Version: 1.0 X-Mailman-Approved-At: Wed, 03 Feb 2021 08:13:07 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Linux Fbdev development list , "linux-doc@vger.kernel.org" , Greg Kroah-Hartman , Randy Dunlap , LKML , dri-devel , Geert Uytterhoeven , Pavel Machek , Linus Torvalds Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Daniel Vetter writes: > Just a quick comment on this: Since most framebuffers are write-combining, > and reads from that tend to be ~3 orders of magnitude slower than writes > (at least on the pile of machines I looked at here, there's big > differences, and some special streaming cpu instructions to make the > reading side not so slow). > > So scrolling by copying tends to be significantly slower than just > redrawing everything. I know this was the case years ago with AGP as iirc, it doubled ( 4x, 8x ) the PCI clock rate but only for writes wasn't it? I thought this was no longer an issue with PCIe, but if it is, then I guess I'll go ahead with cleaning up the dead code and having it re-render with the larger text buffer. _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel