ERST is a way provided by APEI to save and retrieve hardware error
record to and from some simple persistent storage (such as flash).
The Linux kernel support implementation is quite simple and workable
in NMI context. So it can be used to save hardware error record into
flash in hardware error exception or NMI handler, where other more
complex persistent storage such as disk is not usable. After saving
hardware error records via ERST in hardware error exception or NMI
handler, the error records can be retrieved and logged into disk or
network after a clean reboot.
For more information about ERST, please refer to ACPI Specification
version 4.0, section 17.4.
This patch incorporate fixes from Jin Dongming.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
CC: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Signed-off-by: Len Brown <len.brown@intel.com>
HEST describes error sources in detail; communicating operational
parameters (i.e. severity levels, masking bits, and threshold values)
to OS as necessary. It also allows the platform to report error
sources for which OS would typically not implement support (for
example, chipset-specific error registers).
HEST information may be needed by other subsystems. For example, HEST
PCIE AER error source information describes whether a PCIE root port
works in "firmware first" mode, this is needed by general PCIE AER
error subsystem. So a public HEST tabling parsing interface is
provided.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
