david/ipxe
david/ipxe
Archived
1
0
Fork 0
Code
My fork of git://git.ipxe.org/ipxe.git, it is used for my netboot environment at home.
This repository has been archived on 2020-12-06. You can view files and clone it, but cannot push or open issues or pull requests.
4,855 Commits 1 Branch 0 Tags 14 MiB
C 95.2%
Objective-C 1.7%
Assembly 1.3%
Perl 0.7%
Makefile 0.4%
Other 0.6%
ead70bf920
Go to file
Michael Brown ead70bf920 [intel] Apply PBS/PBA errata workaround only to ICH8 PCI device IDs 
ICH8 devices have an errata which requires us to reconfigure the
packet buffer size (PBS) register, and correspondingly adjust the
packet buffer allocation (PBA) register.  The "Intel I/O Controller
Hub ICH8/9/10 and 82566/82567/82562V Software Developer's Manual"
notes for the PBS register that:

  10.4.20   Packet Buffer Size - PBS (01008h; R/W)

  Note: The default setting of this register is 20 KB and is
        incorrect. This register must be programmed to 16 KB.

  Initial value: 0014h
                 0018h (ICH9/ICH10)

It is unclear from this comment precisely which devices require the
workaround to be applied.  We currently attempt to err on the side of
caution: if we detect an initial value of either 0x14 or 0x18 then the
workaround will be applied.  If the workaround is applied
unnecessarily, then the effect should be just that we use less than
the full amount of the available packet buffer memory.

Unfortunately this approach does not play nicely with other device
drivers.  For example, the Linux e1000e driver will rewrite PBA while
assuming that PBS still contains the default value, which can result
in inconsistent values between the two registers, and a corresponding
inability to transmit or receive packets.  Even more unfortunately,
the contents of PBS and PBA are not reset by anything less than a
power cycle, meaning that this error condition will survive a hardware
reset.

The Linux driver (written and maintained by Intel) applies the PBS/PBA
errata workaround only for devices in the ICH8 family, identified via
the PCI device ID.  Adopt a similar approach, using the PCI_ROM()
driver data field to indicate when the workaround is required.

Reported-by: Donald Bindner <dbindner@truman.edu>
Debugged-by: Donald Bindner <dbindner@truman.edu>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
2014-08-21 00:40:22 +01:00
contrib [errdb] Strip platform error code for non-platform-generated errors 2013-04-29 15:36:32 +01:00
src [intel] Apply PBS/PBA errata workaround only to ICH8 PCI device IDs 2014-08-21 00:40:22 +01:00
COPYING Initial revision 2005-05-17 16:44:57 +00:00
COPYRIGHTS [build] Rename gPXE to iPXE 2010-04-19 23:43:39 +01:00
README [doc] Re-add README file 2010-05-28 00:03:47 +01:00

README 

iPXE README File

Quick start guide:

   cd src
   make

For any more detailed instructions, see http://ipxe.org