From patchwork Wed Jul 14 14:57:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 477699 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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 497D4C11F69 for ; Wed, 14 Jul 2021 14:58:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3496D61106 for ; Wed, 14 Jul 2021 14:58:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239518AbhGNPBG (ORCPT ); Wed, 14 Jul 2021 11:01:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39258 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232389AbhGNPBE (ORCPT ); Wed, 14 Jul 2021 11:01:04 -0400 Received: from baptiste.telenet-ops.be (baptiste.telenet-ops.be [IPv6:2a02:1800:120:4::f00:13]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05AFCC061760 for ; Wed, 14 Jul 2021 07:58:12 -0700 (PDT) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed10:bcf3:b2b1:dff6:480b]) by baptiste.telenet-ops.be with bizsmtp id V2yB250014sai0K012yBy8; Wed, 14 Jul 2021 16:58:11 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1m3gKw-001AEh-Om; Wed, 14 Jul 2021 16:58:10 +0200 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1m3gKv-00AcN1-RD; Wed, 14 Jul 2021 16:58:09 +0200 From: Geert Uytterhoeven To: David Airlie , Daniel Vetter , Maxime Ripard Cc: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH resend 0/5] video: fbdev: ssd1307fb: Optimizations and improvements Date: Wed, 14 Jul 2021 16:57:59 +0200 Message-Id: <20210714145804.2530727-1-geert@linux-m68k.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org Hi all, This patch series optimizes console operations on ssd1307fb, after the customary fixes and cleanups. Currently, each screen update triggers an I2C transfer of all screen data, up to 1 KiB of data for a 128x64 display, which takes at least 20 ms in Fast mode. While many displays are smaller, and thus require less data to be transferred, 20 ms is still an optimistic value, as the actual data transfer may be much slower, especially on bitbanged I2C drivers. After this series, the amount of data transfer is reduced, as fillrect, copyarea, and imageblit only update the rectangle that changed. This has been tested on an Adafruit FeatherWing OLED with an SSD1306 controller and a 128x32 OLED, connected to an OrangeCrab ECP5 FPGA board running a 64 MHz VexRiscv RISC-V softcore, where it reduced the CPU usage for blinking the cursor from more than 70% to ca. 10%. Thanks for your comments! Geert Uytterhoeven (5): video: fbdev: ssd1307fb: Propagate errors via ssd1307fb_update_display() video: fbdev: ssd1307fb: Simplify ssd1307fb_update_display() video: fbdev: ssd1307fb: Extract ssd1307fb_set_address_range() video: fbdev: ssd1307fb: Optimize screen updates video: fbdev: ssd1307fb: Cache address ranges drivers/video/fbdev/ssd1307fb.c | 143 +++++++++++++++++++++----------- 1 file changed, 96 insertions(+), 47 deletions(-)