Sherlock's blog

This document shows how to use an IO BAR in PCIe device. Currently there is few devices supported IO BAR, however, when we have a card which needs to use IO BAR, this document shares a basic logic about it

This doc is an analysis note about ATS feature in PCIe/SMMU

In Ubuntu14.04, when running coccinelle, it will fail. So we install it manually to make patch check. This note helps to remember the steps.

From mj.ucw.cz/sw/pciutils we can get the code of lspci/setpci, which are two useful tools to debug PCIe related problems. This doc just introduces these two tools and also the sysfs interfaces which can be used in PCIe problem debug.

这篇笔记记录驱动程序中mmap的写法，以及相关的调试过程。同样代码在： https://github.com/wangzhou/scull.git

这篇文章在note1的基础上，进一步记录实现一个ioctl要注意的地方。相关的代码在： https://github.com/wangzhou/scull.git, tag: scull_2

LDD3的第三章介绍了一个简单的字符设备，实现了read/write/open/release等回调函数。 网上有LDD3自带的源代码，为了方便查找，我把官方源代码放到了: https://github.com/wangzhou/ldd3.git 自己实现的代码(第三章的简易字符设备)放在了：https://github.com/wangzhou/scull.git 本文只是记录一下实现中遇到的需要注意的地方，适合驱动入门的读者。

本文记录C语言位运算的一些corner

本文介绍C语言里的volatile关键词的使用方法。

本文记录一种遇到git am冲突时的解决办法