Documentation/ABI/testing/sysfs-platform-dfl-port

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-platform-dfl-port

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/sysfs-platform-dfl-port
Extension
[no extension]
Size
3776 bytes
Lines
102
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: Documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

What:		/sys/bus/platform/devices/dfl-port.0/id
Date:		June 2018
KernelVersion:	4.19
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Read-only. It returns id of this port. One DFL FPGA device
		may have more than one port. Userspace could use this id to
		distinguish different ports under same FPGA device.

What:		/sys/bus/platform/devices/dfl-port.0/afu_id
Date:		June 2018
KernelVersion:	4.19
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Read-only. User can program different PR bitstreams to FPGA
		Accelerator Function Unit (AFU) for different functions. It
		returns uuid which could be used to identify which PR bitstream
		is programmed in this AFU.

What:		/sys/bus/platform/devices/dfl-port.0/power_state
Date:		August 2019
KernelVersion:	5.4
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Read-only. It reports the APx (AFU Power) state, different APx
		means different throttling level. When reading this file, it
		returns "0" - Normal / "1" - AP1 / "2" - AP2 / "6" - AP6.

What:		/sys/bus/platform/devices/dfl-port.0/ap1_event
Date:		August 2019
KernelVersion:	5.4
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Read-write. Read this file for AP1 (AFU Power State 1) event.
		It's used to indicate transient AP1 state. Write 1 to this
		file to clear AP1 event.

What:		/sys/bus/platform/devices/dfl-port.0/ap2_event
Date:		August 2019
KernelVersion:	5.4
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Read-write. Read this file for AP2 (AFU Power State 2) event.
		It's used to indicate transient AP2 state. Write 1 to this
		file to clear AP2 event.

What:		/sys/bus/platform/devices/dfl-port.0/ltr
Date:		August 2019
KernelVersion:	5.4
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Read-write. Read or set AFU latency tolerance reporting value.
		Set ltr to 1 if the AFU can tolerate latency >= 40us or set it
		to 0 if it is latency sensitive.

What:		/sys/bus/platform/devices/dfl-port.0/userclk_freqcmd
Date:		August 2019
KernelVersion:	5.4
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Write-only. User writes command to this interface to set
		userclock to AFU.

What:		/sys/bus/platform/devices/dfl-port.0/userclk_freqsts
Date:		August 2019
KernelVersion:	5.4
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Read-only. Read this file to get the status of issued command
		to userclck_freqcmd.

What:		/sys/bus/platform/devices/dfl-port.0/userclk_freqcntrcmd
Date:		August 2019
KernelVersion:	5.4
Contact:	Wu Hao <hao.wu@intel.com>
Description:	Write-only. User writes command to this interface to set
		userclock counter.

Annotation

Implementation Notes