Commit 9e05c864 authored by Jens Axboe's avatar Jens Axboe
Browse files

Merge branch 'master' into test 

* master: (688 commits)
  dt-bindings: mailbox: qcom: Document the APCS clock binding
  mailbox: qcom: Create APCS child device for clock controller
  mailbox: qcom: Convert APCS IPC driver to use regmap
  KVM/SVM: Allow direct access to MSR_IA32_SPEC_CTRL
  KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRL
  KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES
  KVM/x86: Add IBPB support
  KVM/x86: Update the reverse_cpuid list to include CPUID_7_EDX
  pinctrl: remove include file from <linux/device.h>
  firmware: dmi: handle missing DMI data gracefully
  firmware: dmi_scan: Fix handling of empty DMI strings
  firmware: dmi_scan: Drop dmi_initialized
  firmware: dmi: Optimize dmi_matches
  Revert "defer call to mem_cgroup_sk_alloc()"
  soreuseport: fix mem leak in reuseport_add_sock()
  net: qlge: use memmove instead of skb_copy_to_linear_data
  net: qed: use correct strncpy() size
  net: cxgb4: avoid memcpy beyond end of source buffer
  cls_u32: add missing RCU annotation.
  r8152: set rx mode early when linking on
  ...
parents 3c15f3f5 35277995

Documentation/ABI/testing/rtc-cdev

0 → 100644
+42 −0
Original line number Diff line number Diff line 
What:		/dev/rtcX

Date:		April 2005

KernelVersion:	2.6.12

Contact:	linux-rtc@vger.kernel.org

Description:

		The ioctl interface to drivers for real-time clocks (RTCs).

		Following actions are supported:



		* RTC_RD_TIME, RTC_SET_TIME: Read or set the RTC time. Time

		  format is a Gregorian calendar date and 24 hour wall clock

		  time.



		* RTC_AIE_ON, RTC_AIE_OFF: Enable or disable the alarm interrupt

		  for RTCs that support alarms



		* RTC_ALM_READ, RTC_ALM_SET: Read or set the alarm time for

		  RTCs that support alarms. Can be set upto 24 hours in the

		  future. Requires a separate RTC_AIE_ON call to enable the

		  alarm interrupt. (Prefer to use RTC_WKALM_*)



		* RTC_WKALM_RD, RTC_WKALM_SET: For RTCs that support a more

		  powerful interface, which can issue alarms beyond 24 hours and

		  enable IRQs in the same request.



		* RTC_PIE_ON, RTC_PIE_OFF: Enable or disable the periodic

		  interrupt for RTCs that support periodic interrupts.



		* RTC_UIE_ON, RTC_UIE_OFF: Enable or disable the update

		  interrupt for RTCs that support it.



		* RTC_IRQP_READ, RTC_IRQP_SET: Read or set the frequency for

		  periodic interrupts for RTCs that support periodic interrupts.

		  Requires a separate RTC_PIE_ON call to enable the periodic

		  interrupts.



		The ioctl() calls supported by the older /dev/rtc interface are

		also supported by the newer RTC class framework. However,

		because the chips and systems are not standardized, some PC/AT

		functionality might not be provided. And in the same way, some

		newer features -- including those enabled by ACPI -- are exposed

		by the RTC class framework, but can't be supported by the older

		driver.

Documentation/ABI/testing/sysfs-class-ocxl

0 → 100644
+35 −0
Original line number Diff line number Diff line 
What:		/sys/class/ocxl/<afu name>/afu_version

Date:		January 2018

Contact:	linuxppc-dev@lists.ozlabs.org

Description:	read only

		Version of the AFU, in the format <major>:<minor>

		Reflects what is read in the configuration space of the AFU



What:		/sys/class/ocxl/<afu name>/contexts

Date:		January 2018

Contact:	linuxppc-dev@lists.ozlabs.org

Description:	read only

		Number of contexts for the AFU, in the format <n>/<max>

		where:

			n:	number of currently active contexts, for debug

			max:	maximum number of contexts supported by the AFU



What:		/sys/class/ocxl/<afu name>/pp_mmio_size

Date:		January 2018

Contact:	linuxppc-dev@lists.ozlabs.org

Description:	read only

		Size of the per-process mmio area, as defined in the

		configuration space of the AFU



What:		/sys/class/ocxl/<afu name>/global_mmio_size

Date:		January 2018

Contact:	linuxppc-dev@lists.ozlabs.org

Description:	read only

		Size of the global mmio area, as defined in the

		configuration space of the AFU



What:		/sys/class/ocxl/<afu name>/global_mmio_area

Date:		January 2018

Contact:	linuxppc-dev@lists.ozlabs.org

Description:	read/write

		Give access the global mmio area for the AFU

Documentation/ABI/testing/sysfs-class-rtc

0 → 100644
+91 −0
Original line number Diff line number Diff line 
What:		/sys/class/rtc/

Date:		March 2006

KernelVersion:	2.6.17

Contact:	linux-rtc@vger.kernel.org

Description:

		The rtc/ class subdirectory belongs to the RTC subsystem.



What:		/sys/class/rtc/rtcX/

Date:		March 2006

KernelVersion:	2.6.17

Contact:	linux-rtc@vger.kernel.org

Description:

		The /sys/class/rtc/rtc{0,1,2,3,...} directories correspond

		to each RTC device.



What:		/sys/class/rtc/rtcX/date

Date:		March 2006

KernelVersion:	2.6.17

Contact:	linux-rtc@vger.kernel.org

Description:

		(RO) RTC-provided date in YYYY-MM-DD format



What:		/sys/class/rtc/rtcX/hctosys

Date:		September 2009

KernelVersion:	2.6.32

Contact:	linux-rtc@vger.kernel.org

Description:

		(RO) 1 if the RTC provided the system time at boot via the

		CONFIG_RTC_HCTOSYS kernel option, 0 otherwise



What:		/sys/class/rtc/rtcX/max_user_freq

Date:		October 2007

KernelVersion:	2.6.24

Contact:	linux-rtc@vger.kernel.org

Description:

		(RW) The maximum interrupt rate an unprivileged user may request

		from this RTC.



What:		/sys/class/rtc/rtcX/name

Date:		March 2006

KernelVersion:	2.6.17

Contact:	linux-rtc@vger.kernel.org

Description:

		(RO) The name of the RTC corresponding to this sysfs directory



What:		/sys/class/rtc/rtcX/since_epoch

Date:		March 2006

KernelVersion:	2.6.17

Contact:	linux-rtc@vger.kernel.org

Description:

		(RO) RTC-provided time as the number of seconds since the epoch



What:		/sys/class/rtc/rtcX/time

Date:		March 2006

KernelVersion:	2.6.17

Contact:	linux-rtc@vger.kernel.org

Description:

		(RO) RTC-provided time in 24-hour notation (hh:mm:ss)



What:		/sys/class/rtc/rtcX/*/nvmem

Date:		February 2016

KernelVersion:	4.6

Contact:	linux-rtc@vger.kernel.org

Description:

		(RW) The non volatile storage exported as a raw file, as

		described in Documentation/nvmem/nvmem.txt



What:		/sys/class/rtc/rtcX/offset

Date:		February 2016

KernelVersion:	4.6

Contact:	linux-rtc@vger.kernel.org

Description:

		(RW) The amount which the rtc clock has been adjusted in

		firmware. Visible only if the driver supports clock offset

		adjustment. The unit is parts per billion, i.e. The number of

		clock ticks which are added to or removed from the rtc's base

		clock per billion ticks. A positive value makes a day pass more

		slowly, longer, and a negative value makes a day pass more

		quickly.



What:		/sys/class/rtc/rtcX/wakealarm

Date:		February 2007

KernelVersion:	2.6.20

Contact:	linux-rtc@vger.kernel.org

Description:

		(RW) The time at which the clock will generate a system wakeup

		event. This is a one shot wakeup event, so must be reset after

		wake if a daily wakeup is required. Format is seconds since the

		epoch by default, or if there's a leading +, seconds in the

		future, or if there is a leading +=, seconds ahead of the

		current alarm.

Documentation/accelerators/ocxl.rst

0 → 100644
+160 −0
Original line number Diff line number Diff line 
========================================================

OpenCAPI (Open Coherent Accelerator Processor Interface)

========================================================



OpenCAPI is an interface between processors and accelerators. It aims

at being low-latency and high-bandwidth. The specification is

developed by the `OpenCAPI Consortium <http://opencapi.org/>`_.



It allows an accelerator (which could be a FPGA, ASICs, ...) to access

the host memory coherently, using virtual addresses. An OpenCAPI

device can also host its own memory, that can be accessed from the

host.



OpenCAPI is known in linux as 'ocxl', as the open, processor-agnostic

evolution of 'cxl' (the driver for the IBM CAPI interface for

powerpc), which was named that way to avoid confusion with the ISDN

CAPI subsystem.





High-level view

===============



OpenCAPI defines a Data Link Layer (DL) and Transaction Layer (TL), to

be implemented on top of a physical link. Any processor or device

implementing the DL and TL can start sharing memory.



::



  +-----------+                         +-------------+

  |           |                         |             |

  |           |                         | Accelerated |

  | Processor |                         |  Function   |

  |           |  +--------+             |    Unit     |  +--------+

  |           |--| Memory |             |    (AFU)    |--| Memory |

  |           |  +--------+             |             |  +--------+

  +-----------+                         +-------------+

       |                                       |

  +-----------+                         +-------------+

  |    TL     |                         |    TLX      |

  +-----------+                         +-------------+

       |                                       |

  +-----------+                         +-------------+

  |    DL     |                         |    DLX      |

  +-----------+                         +-------------+

       |                                       |

       |                   PHY                 |

       +---------------------------------------+







Device discovery

================



OpenCAPI relies on a PCI-like configuration space, implemented on the

device. So the host can discover AFUs by querying the config space.



OpenCAPI devices in Linux are treated like PCI devices (with a few

caveats). The firmware is expected to abstract the hardware as if it

was a PCI link. A lot of the existing PCI infrastructure is reused:

devices are scanned and BARs are assigned during the standard PCI

enumeration. Commands like 'lspci' can therefore be used to see what

devices are available.



The configuration space defines the AFU(s) that can be found on the

physical adapter, such as its name, how many memory contexts it can

work with, the size of its MMIO areas, ...







MMIO

====



OpenCAPI defines two MMIO areas for each AFU:



* the global MMIO area, with registers pertinent to the whole AFU.

* a per-process MMIO area, which has a fixed size for each context.







AFU interrupts

==============



OpenCAPI includes the possibility for an AFU to send an interrupt to a

host process. It is done through a 'intrp_req' defined in the

Transaction Layer, specifying a 64-bit object handle which defines the

interrupt.



The driver allows a process to allocate an interrupt and obtain its

64-bit object handle, that can be passed to the AFU.







char devices

============



The driver creates one char device per AFU found on the physical

device. A physical device may have multiple functions and each

function can have multiple AFUs. At the time of this writing though,

it has only been tested with devices exporting only one AFU.



Char devices can be found in /dev/ocxl/ and are named as:

/dev/ocxl/<AFU name>.<location>.<index>



where <AFU name> is a max 20-character long name, as found in the

config space of the AFU.

<location> is added by the driver and can help distinguish devices

when a system has more than one instance of the same OpenCAPI device.

<index> is also to help distinguish AFUs in the unlikely case where a

device carries multiple copies of the same AFU.







Sysfs class

===========



An ocxl class is added for the devices representing the AFUs. See

/sys/class/ocxl. The layout is described in

Documentation/ABI/testing/sysfs-class-ocxl







User API

========



open

----



Based on the AFU definition found in the config space, an AFU may

support working with more than one memory context, in which case the

associated char device may be opened multiple times by different

processes.





ioctl

-----



OCXL_IOCTL_ATTACH:



  Attach the memory context of the calling process to the AFU so that

  the AFU can access its memory.



OCXL_IOCTL_IRQ_ALLOC:



  Allocate an AFU interrupt and return an identifier.



OCXL_IOCTL_IRQ_FREE:



  Free a previously allocated AFU interrupt.



OCXL_IOCTL_IRQ_SET_FD:



  Associate an event fd to an AFU interrupt so that the user process

  can be notified when the AFU sends an interrupt.





mmap

----



A process can mmap the per-process MMIO area for interactions with the

AFU.

Documentation/admin-guide/kernel-parameters.txt

+0 −2
Original line number Diff line number Diff line
@@ -2758,8 +2758,6 @@ 
	norandmaps	Don't use address space randomization.  Equivalent to

			echo 0 > /proc/sys/kernel/randomize_va_space



	noreplace-paravirt	[X86,IA-64,PV_OPS] Don't patch paravirt_ops



	noreplace-smp	[X86-32,SMP] Don't replace SMP instructions

			with UP alternatives

CRA Git | Maintained and supported by SUSTech CRA and CCSE