随笔分类 - Linux
摘要：From:http://yangman.ca/blog/2009/10/linux-graphics-driver-stack-explained/We get this question a lot aboutradeonhd: “When is 3D going to be supported?”The short answer: never; 3D acceleration is the domain ofMesa.But, of course, it’s not as simple as that. For the long answer, read on…More than Meet
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摘要：From:http://dri.sourceforge.net/doc/DRIintro.htmlBrian Paul(brian@tungstengraphics.com)10 August 2000This document is an introduction and high-level user guide for the Direct Rendering Infrastructure (DRI). It describes the goals of the DRI project, some of its history, the current state, the develo
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摘要：From:http://kerneltrap.org/mailarchive/linux-kernel/2008/4/29/1657814Amidssomeheavyflaming,it'sclearthatthereisalotofconfusiononhowcachabilityandioremapcooperateonx86onahardwarelevel,andhowthisinteractswithLinux(bothbefore2.6.24andincurrenttrees).Thisemailtriestodescribethevariousaspectsandconst
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摘要："ARM DMA-Mapping Framework Redesign and IOMMU integration.pdf" mentioned in this article is here(good to read):/Files/super119/ARM-DMA-Mapping-Framework-Redesign-and-IOMMU-integration.pdfHello eveyone,On Linaro Memory Management meeting in Budapest (May 2011) we havediscussed about the des
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摘要：+ Architecture of a DRM driver+i ----------------------------++Written by Laurent Pinchart <laurent.pinchart@ideasonboard.com>+Last revised: May 30, 2012+++1. Driver initialization+------------------------++- Create a static struct drm_driver instance and register it at probe() time+ with drm_
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摘要：1. DMABUF can be used as a wrapper to encapsulate other memory management frameworks. All these memory management framework(I mean mostly for graphics), buffer is the keypoint. DMABUF defines a standard buffer structure. So DMABUF can be used as a wrapper for TTM/GEM/Android ION... and etc. Notice D
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摘要：From: http://lwn.net/Articles/447405/The problem of allocating large chunks of physically-contiguous memory has often been discussed in these pages. Virtual memory, by its nature, tends to scatter pages throughout the system; the kernel does not have to be running for long before free pages which ha
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摘要：From: http://lwn.net/Articles/283798/NOTE: Currently the buffer creation/read/write are implemented by driver specified ioctls. So right now you can't find functions like "drm_gem_create" in kernel sources.And that's also why we need "dumb buffer" in drm's ioctls(dumb
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摘要：From: http://lwn.net/Articles/257417/The management of video hardware has long been an area of weakness in the Linux system (and free operating systems in general). The X Window System tends to get a lot of the blame for problems in this area, but the truth of the matter is that the problems are mor
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摘要：From: http://lwn.net/Articles/283793/Getting high-performance, three-dimensional graphics working under Linux is quite a challenge even when the fundamental hardware programming information is available. One component of this problem is memory management: a graphics processor (GPU) is, essentially,
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摘要：From: http://lwn.net/Articles/454389/CPUs may not have gotten hugely faster in recent years, but they have gained in other ways; a typical system-on-chip (SoC) device now has a number of peripherals which would qualify as reasonably powerful CPUs in their own right. More powerful devices with direct
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摘要：From: http://www.cnblogs.com/bravery/archive/2012/06/27/2560611.html概述 想必在linux上写过程序的同学都有分析进程占用多少内存的经历，或者被问到这样的问题——你的程序在运行时占用了多少内存（物理内存）？通常我们可以通过top命令查看进程占用了多少内存。这里我们可以看到VIRT、RES和SHR三个重要的指标，他们分别代表什么意思呢？这是本文需要跟大家一起探讨的问题。当然如果更加深入一点，你可能会问进程所占用的那些物理内存都用在了哪些地方？这时候top命令可能不能给到你你所想要的答案了，不过我们可以分析proc文件系统提供的s
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摘要：转自：http://blog.csdn.net/thegameisfives/article/details/7308458什么是ION ?我的理解就是google在android4.0引入的一种内存管理器，来替代之前各个芯片厂家自己的方案..以下是网上找到的：it has become clear that PMEM is considered obsolete and will be replaced by the ION memory manager . ION is a generalized memory manager that Google introduced in the A
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摘要：From: http://zhanglinbao.bokee.com/5408080.html 申明：这份文档是按照自由软件开放源代码的精神发布的，任何人可以免费获得、使用和重新发布，但是你没有限制别人重新发布你发布内容的权利。发布本文的目的是希望它能对读者有用，但没有任何担保，甚至没有适合特定目的的隐含的担保。更详细的情况请参阅GNU通用公共许可证(GPL)，以及GNU自由文档协议(GFDL)。 几乎每一种外设都是通过读写设备上的寄存器来进行的。外设寄存器也称为“I/O端口”，通常包括：控制寄存器、状态寄存器和数据寄存器三大类，而且一个外设的寄存器通常被连续地编址。CPU对外设IO端口...
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摘要：From: http://www.x.org/wiki/Development/Documentation/HowVideoCardsWorkSo you want to know how modern video cards work. Here goes...Modern video cards usually have several common features:Video RamDisplay control2D engine3D engineOverlayHW sprites (cursor, icon, etc.)AGP/PCI/PCIEApertures (registers
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摘要：From: http://blog.csdn.net/do2jiang/article/details/5450839几乎每一种外设都是通过读写设备上的寄存器来进行的，通常包括控制寄存器、状态寄存器和数据寄存器三大类，外设的寄存器通常被连续地编址。根据CPU体系结构的不同，CPU对IO端口的编址方式有两种： （1）I/O映射方式（I/O-mapped） 典型地，如X86处理器为外设专门实现了一个单独的地址空间，称为"I/O地址空间"或者"I/O端口空间"，CPU通过专门的I/O指令（如X86的IN和OUT指令）来访问这一空间中的地址单元。 （2）内存映射
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摘要：From: http://ariejan.net/2009/10/26/how-to-create-and-apply-a-patch-with-gitGit is quite common nowadays and a lot of people are asking me how they can create a patch file. Creating a patch file with git is quite easy to do, you just need to see how it's done a few times.This article will show y
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摘要：这是因为/opt/etc/profile文件中重定义了PATH和LD_LIBRARY_PATH这两个环境变量导致的。这导致所有的linux关键程序，so都来自/opt，而这显然是不对的。因为我们的/opt不是一个完整的系统。而每次登录由于/etc/profile会去source /opt/etc/profile，所以导致了该问题。解决办法很简单，编辑/opt/etc/profile（/etc/profile 只读），将针对PATH和LD_LIBRARY_PATH的设定都注释掉就OK了。
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摘要：From: http://hi.baidu.com/serial_story/blog/item/d40d49c6907212129c163ded.html 如何调整Linux内核启动中的驱动初始化顺序【问题】此处我要实现的是将芯片的ID用于网卡MAC地址，网卡驱动是enc28j60_init。但是，读取芯片ID的函数，在as352x_afe_init模块中，所以要先初始化as352x_afe_init。此处，内核编译完之后，在生成的system.map中可以看到，enc28j60_init在as352x_afe_init之前，所以，无法去读芯片ID。所以我们的目标是，将as352x_afe_
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摘要：RT.
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