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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 161F5C3A5A2 for ; Tue, 3 Sep 2019 18:46:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E7F822168B for ; Tue, 3 Sep 2019 18:46:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725914AbfICSqW (ORCPT ); Tue, 3 Sep 2019 14:46:22 -0400 Received: from pio-pvt-msa1.bahnhof.se ([79.136.2.40]:36804 "EHLO pio-pvt-msa1.bahnhof.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725882AbfICSqW (ORCPT ); Tue, 3 Sep 2019 14:46:22 -0400 Received: from localhost (localhost [127.0.0.1]) by pio-pvt-msa1.bahnhof.se (Postfix) with ESMTP id 6D059417A8; Tue, 3 Sep 2019 20:46:20 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at bahnhof.se Received: from pio-pvt-msa1.bahnhof.se ([127.0.0.1]) by localhost (pio-pvt-msa1.bahnhof.se [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id mNoJkj6Kk36H; Tue, 3 Sep 2019 20:46:19 +0200 (CEST) Received: from localhost (h-41-252.A163.priv.bahnhof.se [46.59.41.252]) (Authenticated sender: mb547485) by pio-pvt-msa1.bahnhof.se (Postfix) with ESMTPA id 8493E4179C; Tue, 3 Sep 2019 20:46:19 +0200 (CEST) Date: Tue, 3 Sep 2019 20:46:19 +0200 From: Fredrik Noring To: "Maciej W. Rozycki" Cc: Jiaxun Yang , linux-mips@vger.kernel.org Subject: Re: [PATCH 094/120] MIPS: PS2: FB: Frame buffer driver for the PlayStation 2 Message-ID: <20190903184619.GA31812@sx9> References: <4927c42fb3401c42c4c5a077f272331ac79d80b1.1567326213.git.noring@nocrew.org> <1003c9cc-c30e-00a7-7494-4f1cb4862e88@flygoat.com> <20190902144007.GA2479@sx9> <2ac424e5-017b-5892-ef38-fe25ec5f38d1@flygoat.com> <20190903174212.GA22657@sx9> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org > Hmm, why do you think this would be unacceptable? Do you expect your > code to cause unjustified maintenance burden once integrated? I suppose it can be implemented quite nicely, with a bit of effort. Steps to be taken: 1. A font needs to be linked with the early boot code. I'm using acorndata_8x8 from lib/fonts/font_acorn_8x8.c, but any font would do. 2. A single, or small set of, video resolutions need to be selected. I chose 1920x1080p and wrote those values to the Graphics Synthesizer video clock registers. A complete video mode line parser seems excessive, unless that code can be shared with the boot code somehow. 3. Implement clear_screen() and plot(x, y) for a single pixel using DMA commands to the Graphics Synthesizer. [ Clearing the screen can be done by plotting the whole screen, but it was somewhat slow. ] 4. Implement prom_putchar() using plot() for the given font. Steps (1) and (4) could be generic code. Fredrik