[PATCH v3 9/9] ACPI: APEI: EINJ: Update the documentation for EINJv2 support

Zaid Alali
2025-02-10T18:37:41Z

Add documentation for the updated ACPI specs for EINJv2(1)(2)

(1)https://bugzilla.tianocore.org/show_bug.cgi?id=4615
(2)https://bugzilla.tianocore.org/attachment.cgi?id=1446

Signed-off-by: Zaid Alali <zaidal@os.amperecomputing.com>
---
.../firmware-guide/acpi/apei/einj.rst | 41 ++++++++++++++++++-
1 file changed, 39 insertions(+), 2 deletions(-)

diff --git a/Documentation/firmware-guide/acpi/apei/einj.rst b/Documentation/firmware-guide/acpi/apei/einj.rst
index c52b9da08fa9..31c848183af0 100644
--- a/Documentation/firmware-guide/acpi/apei/einj.rst
+++ b/Documentation/firmware-guide/acpi/apei/einj.rst
@@ -59,6 +59,9 @@ The following files belong to it:
0x00000200 Platform Correctable
0x00000400 Platform Uncorrectable non-fatal
0x00000800 Platform Uncorrectable fatal
+ V2_0x00000001 EINJV2 Processor Error
+ V2_0x00000002 EINJV2 Memory Error
+ V2_0x00000004 EINJV2 PCI Express Error
================ ===================================

The format of the file contents are as above, except present are only
@@ -85,9 +88,11 @@ The following files belong to it:
Bit 0
Processor APIC field valid (see param3 below).
Bit 1
- Memory address and mask valid (param1 and param2).
+ Memory address and range valid (param1 and param2).
Bit 2
PCIe (seg,bus,dev,fn) valid (see param4 below).
+ Bit 3
+ EINJv2 extension structure is valid

If set to zero, legacy behavior is mimicked where the type of
injection specifies just one bit set, and param1 is multiplexed.
@@ -110,6 +115,7 @@ The following files belong to it:
Used when the 0x1 bit is set in "flags" to specify the APIC id

- param4
+
Used when the 0x4 bit is set in "flags" to specify target PCIe device

- notrigger
@@ -122,6 +128,18 @@ The following files belong to it:
this actually works depends on what operations the BIOS actually
includes in the trigger phase.

+- einjv2_component_count
+
+ The value from this file is used to set the "Component Array Count"
+ field of EINJv2 Extension Structure.
+
+- einjv2_component_array
+
+ The contents of this file are used to set the "Component Array" field
+ of the EINJv2 Extension Structure. The expected format is hex values
+ for component id and syndrome separated by space, and multiple
+ components are separated by new line.
+
CXL error types are supported from ACPI 6.5 onwards (given a CXL port
is present). The EINJ user interface for CXL error types is at
<debugfs mount point>/cxl. The following files belong to it:
@@ -139,7 +157,6 @@ is present). The EINJ user interface for CXL error types is at
under <debugfs mount point>/apei/einj, while CXL 1.1/1.0 port injections
must use this file.

-
BIOS versions based on the ACPI 4.0 specification have limited options
in controlling where the errors are injected. Your BIOS may support an
extension (enabled with the param_extension=1 module parameter, or boot
@@ -194,6 +211,26 @@ An error injection example::
# echo 0x8 > error_type # Choose correctable memory error
# echo 1 > error_inject # Inject now

+An EINJv2 error injection example::
+
+ # cd /sys/kernel/debug/apei/einj
+ # cat available_error_type # See which errors can be injected
+ 0x00000002 Processor Uncorrectable non-fatal
+ 0x00000008 Memory Correctable
+ 0x00000010 Memory Uncorrectable non-fatal
+ 0x00000001 EINJV2 Processor Error
+ 0x00000002 EINJV2 Memory Error
+
+ # echo 0x12345000 > param1 # Set memory address for injection
+ # echo 0xfffffffffffff000 > param2 # Range - anywhere in this page
+ # comp_arr="0x1 0x2 # Fill in the component array
+ >0x1 0x4
+ >0x2 0x4"
+ # echo "$comp_arr" > einjv2_component_array
+ # echo V2_0x2 > error_type # Choose EINJv2 memory error
+ # echo 0xa > flags # set flags to indicate EINJv2
+ # echo 1 > error_inject # Inject now
+
You should see something like this in dmesg::

[22715.830801] EDAC sbridge MC3: HANDLING MCE MEMORY ERROR
--
2.34.1