readme.plx9052

关于linux中pci驱动的一些代码,实现了一些功能

Linux driver for PLX9052 based PCMCIA bridges
=============================================

This is a Linux driver for PLX9052 based PCMCIA-to-PCI bridges commonly
used in "PCI wireless cards" that have a PCMCIA wireless card inside. 
If you remove the card, the rest is a PCMCIA bridge that this driver is
meant to support.

It is possible to use the adapter with other cards.  However, there are
significant limitations stemming both from hardware and software
problems.

PLX9052 based bridges don't support variable voltage.  Only 5V cards are
supported.  A 3.3V card may be damaged if you insert it into the socket. 
You have been warned!

CardBus cards are also unsupported for hardware reasons.  You are likely
to damage them if you try to use them with a PLX9052 based bridge.

Memory cards without CIS are not supported.  There is no way to detect
them.  IDE cards don't work either for unknown reason.

Only wireless cards and Merlin G201 GPRS cards are known to be supported
at this point.  Three drivers for Prism based wireless card (Orinoco,
linux-wlan-ng and HostAP) already have support for wireless cards
connected through the PLX9052 bridge, and you probably want to use them
for now.

This driver gives you an option to use PCMCIA drivers from those
projects.  Also, it is expected that non-prism based wireless cards
would work with this driver, as well as most network cards.  Well, at
least when we get the wait states right.

This driver can be compiled for Linux PCMCIA in the recent 2.4.x and
2.5.x kernels, as well as for the drivers in the pcmcia-cs package.  In
any case, the driver should be copied to the source tree and the
corresponding patches should be applied to the tree.


Installation
------------

Standalone build:

Run "make", become root and run "make install".  You may need to specify
PCMCIA_PATH and KERNEL_PATH on the "make" command line.

For kernel PCMCIA:

Rename plx9052-24.c (for 2.4 kernels) or plx9052-25.c (for 2.5 kernels)
to plx9052.c and copy it to the drivers/pcmcia/ directory in the Linux
kernel tree.  Patch the kernel sources.  Enable the driver during kernel
configuration.  Compile the kernel and install it.  Reboot.

For pcmcia-cs:

Rename plx9052-24.c to plx9052.c and copy it to the modules/ directory
in the pcmcia-cs source tree.  Patch the pcmcia-cs sources.  Recompile
the sources.  Run "make install".  Reload all PCMCIA modules or reboot.

If the driver was compiled as module, make sure that it's loaded before
the "ds" module by adding following line to /etc/modules.conf:

below ds plx9052

There are also other ways to load the module automatically.  In Red Hat
Linux you can set PCIC=plx9052 in /etc/sysconfig/pcmcia.