robin.thoni/ipxe - git rthoni.com

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>		10 years ago
contrib	[errdb] Strip platform error code for non-platform-generated errors	11 years ago
src	[intel] Apply PBS/PBA errata workaround only to ICH8 PCI device IDs	10 years ago
COPYING	Initial revision	20 years ago
COPYRIGHTS	[build] Rename gPXE to iPXE	15 years ago
README	[doc] Re-add README file	14 years ago

iPXE README File

Quick start guide:

   cd src
   make

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