Linux DMA for Dell Inspiron 5000

Disclaimer: Performing the procedure outlined on this page is at your own risk.
The author provides no guarantees, warranties or any liability with respect to any damages
or loss of data or any other harm resulting from performing any of the procedures outlined on this webpage.

Disclaimer: Performing the procedure outlined on this page is at your own risk.
The author provides no guarantees, warranties or any liability with respect to any damages
or loss of data or any other harm resulting from performing any of the procedures outlined on this webpage.

0. WARNING: Messing with kernel and HD drivers is risky

• Only go ahead if you have read all the steps below and you feel comfortable performing these steps.
• Messing with the kernel and the HD's drivers is risky - if something goes wrong or the drivers described here are not applicable to your hardware,
  your computer might not run anymore or you might get data corruption on your hard disk.
• You should have a boot disk and functioning rescue system and be familiar with it's use in case you can't boot your new kernel after the compile etc.

1. Get the files

• Make sure you have the standard RedHat kernel-source and kernel-headers packages installed.
  (kernel-source-2.2.16-3.i386.rpm, kernel-headers-2.2.16-3.i386.rpm )
• Get the current IDE patch from http://www.linux-ide.org, e.g. ide.2.2.16.all.20000805.patch.gz
• Get the current version of the pcmcia package from http://pcmcia-cs.sourceforge.net/.
  As of 9/3/00, the file to get is pcmcia-cs-3.1.20.tar.gz.
  Make SURE you get the tar.gz source code of this package, NOT the RedHat RPM!!!
• In case something goes wrong, it is good to download a copy of RedHat's kernel-pcmcia package for re-install
  (kernel-pcmcia-cs-2.2.16-3.i386.rpm)
  

2. Apply the patch

• I assume kernel-headers and kernel-source are installed.
• Put the patch ide.2.2.16.all.20000825.patch.gz in /usr/src and uncompress:
  gunzip patch ide.2.2.16.all.20000825.patch.gz
  (Actually, when I downloaded the .gz-file, it was already uncompressed despite the gz suffix.
  If gunzip fails, see if the file is a text file, in that case no need to uncompress...).
• Look at the first line of the patch file, it looks like
  diff -urN linux-2.2.16-pristine/CREDITS linux-2.2.16.d/CREDITS
  You need to put in a symbolic link by executing
  ln -s /usr/src/linux /usr/src/linux-2.2.16.d
  
• Apply the patch: patch -p0 < ide.2.2.16.all.20000825.patch.gz
  There will be messages about missing files for different architectures such as power pc etc. Just hit return twice to skip these files.

3. Configure and compile your kernel

• When you configure the kernel, e.g. with make xconfig, enable the two options for the PIIX driver under block devices, CONFIG_BLK_DEV_PIIX and CONFIG_PIIX_TUNING.
  As an example, here is my kernel configuration kernel_config.
• make xconfig doesn't seem to offer an option to select PCMCIA config. I've compiled the kernel without the pcmcia stuff and compiled the pcmcia package separately as described below.
  The advantage of doing it this way is that you can get the newest version of the pcmcia package.
  The downside is that the install of the new pcmcia package overwrites some of RedHat's startup scripts which needs to be reversed manually as described below.

4. Backup your old pcmcia configuration

• The install of the pcmcia package in step 5 will overwrite some of the RedHat startup scripts.
  This results in the problem that eth0 won't come up automatically after boot.
  To fix this, you must backup the RedHat scripts BEFORE you install the new pcmcia package:
  cp -rp /etc/pcmcia /etc/pcmcia_rh
  cp -p /etc/sysconfig/pcmcia /etc/sysconfig/pcmcia_rh
  cp -p /etc/rc.d/init.d/pcmcia /etc/rc.d/init.d/pcmcia_rh
• If you accidentally overwrite the RH scripts, you can reinstall the kernel-pcmcia-cs rpm, then back-up the scripts and re-install the new pcmcia (step 5 below).

5. Install the new pcmcia package

• The modules directory of your new kernel build (e.g. /lib/modules/2.2.16-3) does not contain a pcmcia subdirectory.
  You CANNOT just copy the pcmcia subdirectory from the old kernel modules into the new module directory.
  Instead, you need to re-compile the pcmcia package while running your new kernel.
• Make sure you are running the kernel you just compiled
• Uncompress the pcmcia package in /usr/src:
  cd /usr/src
  tar xvfz pcmcia-cs-3.1.20.tar.gz
• Configure the pcmcia package:
  cd /usr/src/pcmcia-cs-3.1.20
  make config
  The default options should be good. I've used 'trusting' and said yes to PnP.
  
• Compile and install the package:
  make all
  make install
  When running make install, I got a depmod error about parport_cs.o. This might have to do with the fact that I built the parport support into the kernel instead of building a module.
  I just deleted the parport_cs.o file from the /lib/modules/2.2.16-3/pcmcia directory since I don't need it anyway.

6. Revert to RedHat's pcmcia startup configuration

• By now, everything should be working, however, if you have an ethernet pcmcia card, eth0 won't come up automatically after a reboot.
  It should come up if you type /sbin/ifup eth0 .
• To fix this, revert to the RedHat's configuration (this is also described in the PCMCIA-HOWTO)
  mv /etc/pcmcia/network /etc/pcmcia/network_new
  cp -p /etc/pcmcia_rh/network /etc/pcmcia/network
  mv /etc/pcmcia/network.opts /etc/pcmcia/network.opts_new cp -p /etc/pcmcia_rh/network.opts /etc/pcmcia/network.opts
• Your /etc/pcmcia_rh/network.opts should look like (from PCMCIA-HOWTO):
  if [ -f /etc/sysconfig/network-scripts/ifcfg-$1 ] ; then
  start_fn () {
  if [ "$ONBOOT" = "yes" ] ; then /sbin/ifup $1 ; fi
  }
  stop_fn () {
  /sbin/ifdown $1
  }
  fi
• I also reverted to the old /etc/sysconfig, however, I'm not sure whether it's necessary.

That's it. Hopefully, everything is working fine.
Please send comments to frese01@hotmail.com .

Notes

• In the boot messages you probably see something like
  Sep 4 10:51:44 srini kernel: ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
  From what I understand, one should probably NOT set this to a higher frequency.
  The Intel documentation of the 82371AB PIIX4 IDE interface says that the chipset supports 30 and 33MHz bus frequency and UDMA/33.
  Thus, while the HD supports 66MB/sec transfer rate, the highest the controller seems to be capable of is 33MB/sec.