Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 60 insertions, 0 deletions

diff --git a/Documentation/gpu/amdgpu/process-isolation.rst b/Documentation/gpu/amdgpu/process-isolation.rst
new file mode 100644
index 000000000..03c4288aa
--- /dev/null
+++ b/Documentation/gpu/amdgpu/process-isolation.rst
@@ -0,0 +1,60 @@
+.. _amdgpu-process-isolation:
+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+ AMDGPU Process Isolation
+=========================
+
+The AMDGPU driver includes a feature that enables automatic process isolation on the graphics engine. This feature serializes access to the graphics engine and adds a cleaner shader which clears the Local Data Store (LDS) and General Purpose Registers (GPRs) between jobs. All processes using the GPU, including both graphics and compute workloads, are serialized when this feature is enabled. On GPUs that support partitionable graphics engines, this feature can be enabled on a per-partition basis.
+
+In addition, there is an interface to manually run the cleaner shader when the use of the GPU is complete. This may be preferable in some use cases, such as a single-user system where the login manager triggers the cleaner shader when the user logs out.
+
+Process Isolation
+=================
+
+The `run_cleaner_shader` and `enforce_isolation` sysfs interfaces allow users to manually execute the cleaner shader and control the process isolation feature, respectively.
+
+Partition Handling
+------------------
+
+The `enforce_isolation` file in sysfs can be used to enable process isolation and automatic shader cleanup between processes. On GPUs that support graphics engine partitioning, this can be enabled per partition. The partition and its current setting (0 disabled, 1 enabled) can be read from sysfs. On GPUs that do not support graphics engine partitioning, only a single partition will be present. Writing 1 to the partition position enables enforce isolation, writing 0 disables it.
+
+Example of enabling enforce isolation on a GPU with multiple partitions:
+
+.. code-block:: console
+
+    $ echo 1 0 1 0 > /sys/class/drm/card0/device/enforce_isolation
+    $ cat /sys/class/drm/card0/device/enforce_isolation
+    1 0 1 0
+
+The output indicates that enforce isolation is enabled on zeroth and second partition and disabled on first and third partition.
+
+For devices with a single partition or those that do not support partitions, there will be only one element:
+
+.. code-block:: console
+
+    $ echo 1 > /sys/class/drm/card0/device/enforce_isolation
+    $ cat /sys/class/drm/card0/device/enforce_isolation
+    1
+
+Cleaner Shader Execution
+========================
+
+The driver can trigger a cleaner shader to clean up the LDS and GPR state on the graphics engine. When process isolation is enabled, this happens automatically between processes. In addition, there is a sysfs file to manually trigger cleaner shader execution.
+
+To manually trigger the execution of the cleaner shader, write `0` to the `run_cleaner_shader` sysfs file:
+
+.. code-block:: console
+
+    $ echo 0 > /sys/class/drm/card0/device/run_cleaner_shader
+
+For multi-partition devices, you can specify the partition index when triggering the cleaner shader:
+
+.. code-block:: console
+
+    $ echo 0 > /sys/class/drm/card0/device/run_cleaner_shader # For partition 0
+    $ echo 1 > /sys/class/drm/card0/device/run_cleaner_shader # For partition 1
+    $ echo 2 > /sys/class/drm/card0/device/run_cleaner_shader # For partition 2
+    # ... and so on for each partition
+
+This command initiates the cleaner shader, which will run and complete before any new tasks are scheduled on the GPU.