From 80ade22c06ca115b81dd168e99479c8e09843513 Mon Sep 17 00:00:00 2001 From: Sudeep Dutt Date: Tue, 27 Oct 2020 20:14:15 -0700 Subject: misc: mic: remove the MIC drivers This patch removes the MIC drivers from the kernel tree since the corresponding devices have been discontinued. Removing the dma and char-misc changes in one patch and merging via the char-misc tree is best to avoid any potential build breakage. Cc: Nikhil Rao Reviewed-by: Ashutosh Dixit Signed-off-by: Sudeep Dutt Acked-By: Vinod Koul Reviewed-by: Sherry Sun Link: https://lore.kernel.org/r/8c1443136563de34699d2c084df478181c205db4.1603854416.git.sudeep.dutt@intel.com Signed-off-by: Greg Kroah-Hartman --- Documentation/misc-devices/mic/index.rst | 16 ---- Documentation/misc-devices/mic/mic_overview.rst | 85 ------------------ Documentation/misc-devices/mic/scif_overview.rst | 108 ----------------------- 3 files changed, 209 deletions(-) delete mode 100644 Documentation/misc-devices/mic/index.rst delete mode 100644 Documentation/misc-devices/mic/mic_overview.rst delete mode 100644 Documentation/misc-devices/mic/scif_overview.rst (limited to 'Documentation/misc-devices') diff --git a/Documentation/misc-devices/mic/index.rst b/Documentation/misc-devices/mic/index.rst deleted file mode 100644 index 3a8d06367ef1..000000000000 --- a/Documentation/misc-devices/mic/index.rst +++ /dev/null @@ -1,16 +0,0 @@ -============================================= -Intel Many Integrated Core (MIC) architecture -============================================= - -.. toctree:: - :maxdepth: 1 - - mic_overview - scif_overview - -.. only:: subproject and html - - Indices - ======= - - * :ref:`genindex` diff --git a/Documentation/misc-devices/mic/mic_overview.rst b/Documentation/misc-devices/mic/mic_overview.rst deleted file mode 100644 index 17d956bdaf7c..000000000000 --- a/Documentation/misc-devices/mic/mic_overview.rst +++ /dev/null @@ -1,85 +0,0 @@ -====================================================== -Intel Many Integrated Core (MIC) architecture overview -====================================================== - -An Intel MIC X100 device is a PCIe form factor add-in coprocessor -card based on the Intel Many Integrated Core (MIC) architecture -that runs a Linux OS. It is a PCIe endpoint in a platform and therefore -implements the three required standard address spaces i.e. configuration, -memory and I/O. The host OS loads a device driver as is typical for -PCIe devices. The card itself runs a bootstrap after reset that -transfers control to the card OS downloaded from the host driver. The -host driver supports OSPM suspend and resume operations. It shuts down -the card during suspend and reboots the card OS during resume. -The card OS as shipped by Intel is a Linux kernel with modifications -for the X100 devices. - -Since it is a PCIe card, it does not have the ability to host hardware -devices for networking, storage and console. We provide these devices -on X100 coprocessors thus enabling a self-bootable equivalent -environment for applications. A key benefit of our solution is that it -leverages the standard virtio framework for network, disk and console -devices, though in our case the virtio framework is used across a PCIe -bus. A Virtio Over PCIe (VOP) driver allows creating user space -backends or devices on the host which are used to probe virtio drivers -for these devices on the MIC card. The existing VRINGH infrastructure -in the kernel is used to access virtio rings from the host. The card -VOP driver allows card virtio drivers to communicate with their user -space backends on the host via a device page. Ring 3 apps on the host -can add, remove and configure virtio devices. A thin MIC specific -virtio_config_ops is implemented which is borrowed heavily from -previous similar implementations in lguest and s390. - -MIC PCIe card has a dma controller with 8 channels. These channels are -shared between the host s/w and the card s/w. 0 to 3 are used by host -and 4 to 7 by card. As the dma device doesn't show up as PCIe device, -a virtual bus called mic bus is created and virtual dma devices are -created on it by the host/card drivers. On host the channels are private -and used only by the host driver to transfer data for the virtio devices. - -The Symmetric Communication Interface (SCIF (pronounced as skiff)) is a -low level communications API across PCIe currently implemented for MIC. -More details are available at scif_overview.txt. - -The Coprocessor State Management (COSM) driver on the host allows for -boot, shutdown and reset of Intel MIC devices. It communicates with a COSM -"client" driver on the MIC cards over SCIF to perform these functions. - -Here is a block diagram of the various components described above. The -virtio backends are situated on the host rather than the card given better -single threaded performance for the host compared to MIC, the ability of -the host to initiate DMA's to/from the card using the MIC DMA engine and -the fact that the virtio block storage backend can only be on the host:: - - +----------+ | +----------+ - | Card OS | | | Host OS | - +----------+ | +----------+ - | - +-------+ +--------+ +------+ | +---------+ +--------+ +--------+ - | Virtio| |Virtio | |Virtio| | |Virtio | |Virtio | |Virtio | - | Net | |Console | |Block | | |Net | |Console | |Block | - | Driver| |Driver | |Driver| | |backend | |backend | |backend | - +---+---+ +---+----+ +--+---+ | +---------+ +----+---+ +--------+ - | | | | | | | - | | | |User | | | - | | | |------|------------|--+------|------- - +---------+---------+ |Kernel | - | | | - +---------+ +---+----+ +------+ | +------+ +------+ +--+---+ +-------+ - |MIC DMA | | VOP | | SCIF | | | SCIF | | COSM | | VOP | |MIC DMA| - +---+-----+ +---+----+ +--+---+ | +--+---+ +--+---+ +------+ +----+--+ - | | | | | | | - +---+-----+ +---+----+ +--+---+ | +--+---+ +--+---+ +------+ +----+--+ - |MIC | | VOP | |SCIF | | |SCIF | | COSM | | VOP | | MIC | - |HW Bus | | HW Bus| |HW Bus| | |HW Bus| | Bus | |HW Bus| |HW Bus | - +---------+ +--------+ +--+---+ | +--+---+ +------+ +------+ +-------+ - | | | | | | | - | +-----------+--+ | | | +---------------+ | - | |Intel MIC | | | | |Intel MIC | | - | |Card Driver | | | | |Host Driver | | - +---+--------------+------+ | +----+---------------+-----+ - | | | - +-------------------------------------------------------------+ - | | - | PCIe Bus | - +-------------------------------------------------------------+ diff --git a/Documentation/misc-devices/mic/scif_overview.rst b/Documentation/misc-devices/mic/scif_overview.rst deleted file mode 100644 index 4c8ad9e43706..000000000000 --- a/Documentation/misc-devices/mic/scif_overview.rst +++ /dev/null @@ -1,108 +0,0 @@ -======================================== -Symmetric Communication Interface (SCIF) -======================================== - -The Symmetric Communication Interface (SCIF (pronounced as skiff)) is a low -level communications API across PCIe currently implemented for MIC. Currently -SCIF provides inter-node communication within a single host platform, where a -node is a MIC Coprocessor or Xeon based host. SCIF abstracts the details of -communicating over the PCIe bus while providing an API that is symmetric -across all the nodes in the PCIe network. An important design objective for SCIF -is to deliver the maximum possible performance given the communication -abilities of the hardware. SCIF has been used to implement an offload compiler -runtime and OFED support for MPI implementations for MIC coprocessors. - -SCIF API Components -=================== - -The SCIF API has the following parts: - -1. Connection establishment using a client server model -2. Byte stream messaging intended for short messages -3. Node enumeration to determine online nodes -4. Poll semantics for detection of incoming connections and messages -5. Memory registration to pin down pages -6. Remote memory mapping for low latency CPU accesses via mmap -7. Remote DMA (RDMA) for high bandwidth DMA transfers -8. Fence APIs for RDMA synchronization - -SCIF exposes the notion of a connection which can be used by peer processes on -nodes in a SCIF PCIe "network" to share memory "windows" and to communicate. A -process in a SCIF node initiates a SCIF connection to a peer process on a -different node via a SCIF "endpoint". SCIF endpoints support messaging APIs -which are similar to connection oriented socket APIs. Connected SCIF endpoints -can also register local memory which is followed by data transfer using either -DMA, CPU copies or remote memory mapping via mmap. SCIF supports both user and -kernel mode clients which are functionally equivalent. - -SCIF Performance for MIC -======================== - -DMA bandwidth comparison between the TCP (over ethernet over PCIe) stack versus -SCIF shows the performance advantages of SCIF for HPC applications and -runtimes:: - - Comparison of TCP and SCIF based BW - - Throughput (GB/sec) - 8 + PCIe Bandwidth ****** - + TCP ###### - 7 + ************************************** SCIF %%%%%% - | %%%%%%%%%%%%%%%%%%% - 6 + %%%% - | %% - | %%% - 5 + %% - | %% - 4 + %% - | %% - 3 + %% - | % - 2 + %% - | %% - | % - 1 + - + ###################################### - 0 +++---+++--+--+-+--+--+-++-+--+-++-+--+-++-+- - 1 10 100 1000 10000 100000 - Transfer Size (KBytes) - -SCIF allows memory sharing via mmap(..) between processes on different PCIe -nodes and thus provides bare-metal PCIe latency. The round trip SCIF mmap -latency from the host to an x100 MIC for an 8 byte message is 0.44 usecs. - -SCIF has a user space library which is a thin IOCTL wrapper providing a user -space API similar to the kernel API in scif.h. The SCIF user space library -is distributed @ https://software.intel.com/en-us/mic-developer - -Here is some pseudo code for an example of how two applications on two PCIe -nodes would typically use the SCIF API:: - - Process A (on node A) Process B (on node B) - - /* get online node information */ - scif_get_node_ids(..) scif_get_node_ids(..) - scif_open(..) scif_open(..) - scif_bind(..) scif_bind(..) - scif_listen(..) - scif_accept(..) scif_connect(..) - /* SCIF connection established */ - - /* Send and receive short messages */ - scif_send(..)/scif_recv(..) scif_send(..)/scif_recv(..) - - /* Register memory */ - scif_register(..) scif_register(..) - - /* RDMA */ - scif_readfrom(..)/scif_writeto(..) scif_readfrom(..)/scif_writeto(..) - - /* Fence DMAs */ - scif_fence_signal(..) scif_fence_signal(..) - - mmap(..) mmap(..) - - /* Access remote registered memory */ - - /* Close the endpoints */ - scif_close(..) scif_close(..) -- cgit v1.2.3