Documentation/ABI: Add new attribute for mlxreg-io sysfs interfaces

Add documentation for the new attributes:
- Request and response for access to protetced flashes:
"global_wp_request", "global_wp_response".
Only for systems equipped with BMC - grant can be provided only by
BMC in case its security policy allows to grant access.
- Request to unlock ASICs, which has been shutdown due-to ASIC thermal
event: "shutdown_unlock".
- Data processor Units (DPU) boot progress: "boot_progress".
- DPU reset causes: "reset_aux_pwr_or_reload", "reset_dpu_thermal",
"reset_from_main_board".
- Reset control for DPU components: "perst_rst", "phy_rst", "tpm_rst",
"usbphy_rst".
- DPU Unified Fabric Manager upgrade - "ufm_upgrade".
- Hardware Id of Data Process Unit board - "dpu_id".

Reviewed-by: Michael Shych <[e-mail]>
Signed-off-by: Vadim Pasternak <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Reviewed-by: Ilpo Järvinen <[e-mail]>
Signed-off-by: Ilpo Järvinen <[e-mail]>

Documentation/ABI/stable/sysfs-driver-mlxreg-io

···
 		switch board.
 
 		The file is read only.
+
+What:		/sys/devices/platform/mlxplat/mlxreg-io/hwmon/hwmon*/global_wp_request
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	This file when written 1 activates request to allow access to
+		the write protected flashes. Such request can be performed only
+		for system equipped with BMC (Board Management Controller),
+		which can grant access to protected flashes. In case BMC allows
+		access - it will respond with "global_wp_response". BMC decides
+		regarding time window of granted access. After granted window is
+		expired, BMC will change value back to 0.
+		Default value is 0.
+
+		The file is read/write.
+
+What:		/sys/devices/platform/mlxplat/mlxreg-io/hwmon/hwmon*/global_wp_response
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	This file, when set 1, indicates that access to protected
+		flashes have been granted to host CPU by BMC.
+		Default value is 0.
+
+		The file is read only.
+
+What:		/sys/devices/platform/mlxplat/mlxreg-io/hwmon/hwmon*/shutdown_unlock
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	When ASICs are getting overheated, system protection
+		hardware mechanism enforces system reboot. After system
+		reboot ASICs come up in locked state. To unlock ASICs,
+		this file should be written 1
+		Default value is 0.
+
+		The file is read/write.
+
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/boot_progress
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	These files show the Data Process Unit board boot progress
+		state. Valid states are:
+		- 4 : OS starting.
+		- 5 : OS running.
+		- 6 : Low-Power Standby.
+
+		The file is read only.
+
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/dpu_id
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	This file shows hardware Id of Data Process Unit board.
+
+		The file is read only.
+
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/reset_aux_pwr_or_reload
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/reset_dpu_thermal
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/reset_from_main_board
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	These files expose the cause of the most recent reset of the Data
+		Processing Unit (DPU) board. The possible causes are:
+		- Power auxiliary outage or power reload.
+		- Thermal shutdown.
+		- Reset request from the main board.
+		Value 1 in file means this is reset cause, 0 - otherwise. Only one of
+		the above causes could be 1 at the same time, representing only last
+		reset cause.
+
+		The files are read only.
+
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/perst_rst
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/phy_rst
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/tpm_rst
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/usbphy_rst
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	These files allow to reset hardware components of Data Process
+		Unit board. Respectively PCI, Ethernet PHY, TPM and USB PHY
+		resets.
+		Default values for all the attributes is 1. Writing 0 will
+		cause reset of the related component.
+
+		The files are read/write.
+
+What:		/sys/devices/platform/mlxplat/i2c_mlxcpld.*/i2c-*/i2c-*/*-00**/mlxreg-io.*/hwmon/hwmon*/ufm_upgrade
+Date:		May 2025
+KernelVersion:	6.16
+Contact:	Vadim Pasternak <[e-mail]>
+Description:	These files show status of Unified Fabric Manager upgrade.
+		state. 0 - means upgrade is done, 1 - otherwise.
+
+		The file is read only.