Apr 2, 2020 · 也就是說讀寫PCI的方式有兩種，一種是透過I/O (CF8/CFC)而另一種則是利用MMIO的方式來去讀寫PCI configuration space. 在介紹這兩種讀寫方法以前，我們先來看PCI spec.如何定義Configuration commands。 為了支援階層式的PCI buses，在此使用兩種類型 …

Jul 2, 2014 · This is how you can enumerate your PCI devices by using ports 0xCF8 and 0xCFC. Please note that this code is intended to run from the privileged mode (ring 0), thus it's …

pcie规范在pci规范的基础上，将配置空间扩展到4kb。原来的cf8/cfc方法仍然可以访问所有pcie设备配置空间的头255b，但是该方法访问不了剩下的（4k-255）配置空间。怎么办呢？

explicitly mentioned as CF8/CFC in the datasheets 14. I/O Port CONFIG_ADDRESS (CF8h) • 32 bits (GIMME BUS 0, DEVICE 31 (0x1F), Function 0, offset 0x88) • Port CF8h • Bit 31 when set, all reads and writes to CONFIG_DATA are PCI Configuration transactions ...

我們知道透過I/O space (CF8/CFC)可以Read/Write Configuration space，其中把要讀取該Space的 PFA 填入Config_Address (CF8)後，在Config_Data (CFC)就可以得到該資料。 以Tool RW來示範的話就是利用I/O CF8填入PFA，然後在CFC的Offset 00h可以得到Interrupt Line的值16h，如圖Figure 5所示。 如此，我們可以在EAX的Offset 00h得到我們要讀取的值。 以電子郵件傳送這篇文章BlogThis！ 分享至 X分享至 Facebook分享到 Pinterest.

Aug 27, 2012 · As you know, it can only access to the first 256-byte of the pci confiuration space when using the IO port CF8/CFC, if you want to access the space between 256~4095-byte, you must use ECAM (Enhanced Configuration Access Mechanism), but the annotation above says: extended (4096 bytes per PCI function) configuration space with type 1 accesses.

It turns out that on *some devices* the last 2 DWORDS in config space are actually index/data pairs to allow you to get access to the other registers. So you're technically using an index/data pair of IO writes (CF8/CFC) to now access another index/data pair in …

Jul 30, 2019 · If The top 5 bus bits match, then the NodeID is determined by [22:20], and an NcCfgRd/Wr is sent to that NodeID. If it is not CF8/CFC then the destination NodeID is determined by looking up a target list entry using IO_Addr[15:13] – so the 3 …

Oct 12, 2017 · 访问配置空间的方法有两种：一是通过CF8/CFC io端口的间接访问来访问配置空间；二是通过mmcfg方式，把配置空间映射到memory空间来访问。 对每个配置空间来说，CF8/CFC方式只能访问传统的pci配置空间256字节，而mmcfg访问方式，能访问pcie的整个配置空间4k。 本节以系统的桥片为例，来说明x86系列cpu的地址空间分配。 x86 其他系列cpu的地址空间分配类似。 x86 xeon系列cpu 在32位系统下面，通过PAE (Physical address Extension)机 …

In this video, we'll use a small x86 ASM code to cycle through and discover all the devices under a PCI BUS, using CF8/CFC mechanism.