[tip: x86/platform] x86/platform/uv: Update ABI documentation of /sys/firmware/sgi_uv/

From: tip-bot2 for Justin Ernst
Date: Thu Nov 26 2020 - 13:21:13 EST


The following commit has been merged into the x86/platform branch of tip:

Commit-ID: 7ac2f1017115ece5288465da2906ad23b8b07a65
Gitweb: https://git.kernel.org/tip/7ac2f1017115ece5288465da2906ad23b8b07a65
Author: Justin Ernst <justin.ernst@xxxxxxx>
AuthorDate: Wed, 25 Nov 2020 11:54:43 -06:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Thu, 26 Nov 2020 17:16:45 +01:00

x86/platform/uv: Update ABI documentation of /sys/firmware/sgi_uv/

Update the ABI documentation to describe the sysfs interface provided by
the new uv_sysfs platform driver.

Signed-off-by: Justin Ernst <justin.ernst@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Steve Wahl <steve.wahl@xxxxxxx>
Acked-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Link: https://lkml.kernel.org/r/20201125175444.279074-5-justin.ernst@xxxxxxx
---
Documentation/ABI/testing/sysfs-firmware-sgi_uv | 141 +++++++++++++--
1 file changed, 127 insertions(+), 14 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-firmware-sgi_uv b/Documentation/ABI/testing/sysfs-firmware-sgi_uv
index 66800ba..50e25ce 100644
--- a/Documentation/ABI/testing/sysfs-firmware-sgi_uv
+++ b/Documentation/ABI/testing/sysfs-firmware-sgi_uv
@@ -1,27 +1,140 @@
What: /sys/firmware/sgi_uv/
-Date: August 2008
-Contact: Russ Anderson <rja@xxxxxxx>
+Date: September 2020
+Contact: Justin Ernst <justin.ernst@xxxxxxx>
Description:
The /sys/firmware/sgi_uv directory contains information
- about the SGI UV platform.
+ about the UV platform.

- Under that directory are a number of files::
+ Under that directory are a number of read-only attributes:

partition_id
coherence_id
+ uv_type

The partition_id entry contains the partition id.
- SGI UV systems can be partitioned into multiple physical
+ UV systems can be partitioned into multiple physical
machines, which each partition running a unique copy
- of the operating system. Each partition will have a unique
- partition id. To display the partition id, use the command::
-
- cat /sys/firmware/sgi_uv/partition_id
+ of the operating system. Each partition will have a unique
+ partition id.

The coherence_id entry contains the coherence id.
- A partitioned SGI UV system can have one or more coherence
- domain. The coherence id indicates which coherence domain
- this partition is in. To display the coherence id, use the
- command::
+ A partitioned UV system can have one or more coherence
+ domains. The coherence id indicates which coherence domain
+ this partition is in.
+
+ The uv_type entry contains the hub revision number.
+ This value can be used to identify the UV system version:
+ "3.0" = UV2
+ "5.0" = UV3
+ "7.0" = UV4
+ "7.1" = UV4a
+ "9.0" = UV5
+
+ The /sys/firmware/sgi_uv directory also contains two directories:
+
+ hubs/
+ pcibuses/
+
+ The hubs directory contains a number of hub objects, each representing
+ a UV Hub visible to the BIOS. Each hub object's name is appended by a
+ unique ordinal value (ex. /sys/firmware/sgi_uv/hubs/hub_5)
+
+ Each hub object directory contains a number of read-only attributes:
+
+ cnode
+ location
+ name
+ nasid
+ shared
+ this_partition
+
+ The cnode entry contains the cnode number of the corresponding hub.
+ If a cnode value is not applicable, the value returned will be -1.
+
+ The location entry contains the location string of the corresponding hub.
+ This value is used to physically identify a hub within a system.
+
+ The name entry contains the name of the corresponding hub. This name can
+ be two variants:
+ "UVHub x.x" = A 'node' ASIC, connecting a CPU to the interconnect
+ fabric. The 'x.x' value represents the ASIC revision.
+ (ex. 'UVHub 5.0')
+ "NLxRouter" = A 'router ASIC, only connecting other ASICs to
+ the interconnect fabric. The 'x' value representing
+ the fabric technology version. (ex. 'NL8Router')
+
+ The nasid entry contains the nasid number of the corresponding hub.
+ If a nasid value is not applicable, the value returned will be -1.
+
+ The shared entry contains a boolean value describing whether the
+ corresponding hub is shared between system partitions.
+
+ The this_partition entry contains a boolean value describing whether
+ the corresponding hub is local to the current partition.
+
+ Each hub object directory also contains a number of port objects,
+ each representing a fabric port on the corresponding hub.
+ A port object's name is appended by a unique ordinal value
+ (ex. /sys/firmware/sgi_uv/hubs/hub_5/port_3)
+
+ Each port object directory contains a number of read-only attributes:
+
+ conn_hub
+ conn_port
+
+ The conn_hub entry contains a value representing the unique
+ oridinal value of the hub on the other end of the fabric
+ cable plugged into the port. If the port is disconnected,
+ the value returned will be -1.
+
+ The conn_port entry contains a value representing the unique
+ oridinal value of the port on the other end of the fabric cable
+ plugged into the port. If the port is disconnected, the value
+ returned will be -1.
+
+ Ex:
+ A value of '3' is read from:
+ /sys/firmware/sgi_uv/hubs/hub_5/port_3/conn_hub
+
+ and a value of '6' is read from:
+ /sys/firmware/sgi_uv/hubs/hub_5/port_3/conn_port
+
+ representing that this port is connected to:
+ /sys/firmware/sgi_uv/hubs/hub_3/port_6
+
+
+ The pcibuses directory contains a number of PCI bus objects.
+ Each PCI bus object's name is appended by its PCI bus address.
+ (ex. pcibus_0003:80)
+
+ Each pcibus object has a number of possible read-only attributes:
+
+ type
+ location
+ slot
+ ppb_addr
+ iio_stack
+
+ The type entry contains a value describing the type of IO at
+ the corresponding PCI bus address. Known possible values
+ across all UV versions are:
+ BASE IO
+ PCIe IO
+ PCIe SLOT
+ NODE IO
+ Riser
+ PPB
+
+ The location entry contains the location string of the UV Hub
+ of the CPU physically connected to the corresponding PCI bus.
+
+ The slot entry contains the physical slot number of the
+ corresponding PCI bus. This value is used to physically locate
+ PCI cards within a system.
+
+ The ppb_addr entry contains the PCI address string of the
+ bridged PCI bus. This entry is only present when the PCI bus
+ object type is 'PPB'.

- cat /sys/firmware/sgi_uv/coherence_id
+ The iio_stack entry contains a value describing the IIO stack
+ number that the corresponding PCI bus object is connected to.