Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752038AbdHQBRv (ORCPT ); Wed, 16 Aug 2017 21:17:51 -0400 Received: from mail-io0-f174.google.com ([209.85.223.174]:34285 "EHLO mail-io0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751517AbdHQBRs (ORCPT ); Wed, 16 Aug 2017 21:17:48 -0400 Date: Wed, 16 Aug 2017 21:17:45 -0400 (EDT) From: Nicolas Pitre To: Chris Brandt cc: Alexander Viro , "linux-fsdevel@vger.kernel.org" , "linux-embedded@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH 0/5] cramfs refresh for embedded usage In-Reply-To: Message-ID: References: <20170811192252.19062-1-nicolas.pitre@linaro.org> User-Agent: Alpine 2.20 (LFD 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 614 Lines: 16 On Wed, 16 Aug 2017, Chris Brandt wrote: > I made an example once were all the graphics were RAW and uncompressed > and marked as XIP in AXFS. The result was a large saving of RAM because > as the graphics framework (DirectFB) would copy directly from Flash > whenever it needed to do a background erase or image re-draw (button press > animations). > > Same went for playing MP3 files. The MP3 files were XIP in flash, so > mpg123 pulled from flash directly. I wouldn't have expected mpg123 to mmap() its input files though. If you use read() and not mmap() then you don't get the full benefit. Nicolas