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Merge tag 'ntb-5.20' of https://github.com/jonmason/ntb
Pull NTB updates from Jon Mason: "Non-Transparent Bridge updates. Fix of heap data and clang warnings, support for a new Intel NTB device, and NTB EndPoint Function (EPF) support and the various fixes for that" * tag 'ntb-5.20' of https://github.com/jonmason/ntb: MAINTAINERS: add PCI Endpoint NTB drivers to NTB files NTB: EPF: Tidy up some bounds checks NTB: EPF: Fix error code in epf_ntb_bind() PCI: endpoint: pci-epf-vntb: reduce several globals to statics PCI: endpoint: pci-epf-vntb: fix error handle in epf_ntb_mw_bar_init() PCI: endpoint: Fix Kconfig dependency NTB: EPF: set pointer addr to null using NULL rather than 0 Documentation: PCI: extend subheading underline for "lspci output" section Documentation: PCI: Use code-block block for scratchpad registers diagram Documentation: PCI: Add specification for the PCI vNTB function device PCI: endpoint: Support NTB transfer between RC and EP NTB: epf: Allow more flexibility in the memory BAR map method PCI: designware-ep: Allow pci_epc_set_bar() update inbound map address ntb: intel: add GNR support for Intel PCIe gen5 NTB NTB: ntb_tool: uninitialized heap data in tool_fn_write() ntb: idt: fix clang -Wformat warnings
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‎Documentation/PCI/endpoint/index.rst

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pci-test-howto
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pci-ntb-function
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pci-ntb-howto
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pci-vntb-function
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pci-vntb-howto
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function/binding/pci-test
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function/binding/pci-ntb

‎Documentation/PCI/endpoint/pci-vntb-function.rst

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.. SPDX-License-Identifier: GPL-2.0
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=================
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PCI vNTB Function
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=================
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:Author: Frank Li <Frank.Li@nxp.com>
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The difference between PCI NTB function and PCI vNTB function is
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PCI NTB function need at two endpoint instances and connect HOST1
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and HOST2.
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PCI vNTB function only use one host and one endpoint(EP), use NTB
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connect EP and PCI host
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.. code-block:: text
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+------------+ +---------------------------------------+
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| | | |
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+------------+ | +--------------+
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| NTB | | | NTB |
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| NetDev | | | NetDev |
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+------------+ | +--------------+
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| NTB | | | NTB |
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| Transfer | | | Transfer |
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+------------+ | +--------------+
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| | | | |
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| PCI NTB | | | |
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| EPF | | | |
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| Driver | | | PCI Virtual |
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| | +---------------+ | NTB Driver |
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| | | PCI EP NTB |<------>| |
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| | | FN Driver | | |
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+------------+ +---------------+ +--------------+
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| | | | | |
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| PCI BUS | <-----> | PCI EP BUS | | Virtual PCI |
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| | PCI | | | BUS |
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+------------+ +---------------+--------+--------------+
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PCI RC PCI EP
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Constructs used for Implementing vNTB
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=====================================
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1) Config Region
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2) Self Scratchpad Registers
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3) Peer Scratchpad Registers
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4) Doorbell (DB) Registers
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5) Memory Window (MW)
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Config Region:
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--------------
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It is same as PCI NTB Function driver
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Scratchpad Registers:
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---------------------
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It is appended after Config region.
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.. code-block:: text
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+--------------------------------------------------+ Base
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| |
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| |
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| |
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| Common Config Register |
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| |
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| |
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| |
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+-----------------------+--------------------------+ Base + span_offset
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| | |
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| Peer Span Space | Span Space |
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| | |
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| | |
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+-----------------------+--------------------------+ Base + span_offset
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| | | + span_count * 4
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| | |
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| Span Space | Peer Span Space |
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| | |
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+-----------------------+--------------------------+
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Virtual PCI Pcie Endpoint
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NTB Driver NTB Driver
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Doorbell Registers:
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-------------------
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Doorbell Registers are used by the hosts to interrupt each other.
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Memory Window:
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--------------
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Actual transfer of data between the two hosts will happen using the
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memory window.
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Modeling Constructs:
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====================
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32-bit BARs.
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====== ===============
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BAR NO CONSTRUCTS USED
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====== ===============
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BAR0 Config Region
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BAR1 Doorbell
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BAR2 Memory Window 1
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BAR3 Memory Window 2
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BAR4 Memory Window 3
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BAR5 Memory Window 4
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====== ===============
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64-bit BARs.
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====== ===============================
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BAR NO CONSTRUCTS USED
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====== ===============================
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BAR0 Config Region + Scratchpad
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BAR1
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BAR2 Doorbell
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BAR3
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BAR4 Memory Window 1
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BAR5
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====== ===============================
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‎Documentation/PCI/endpoint/pci-vntb-howto.rst

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.. SPDX-License-Identifier: GPL-2.0
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===================================================================
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PCI Non-Transparent Bridge (NTB) Endpoint Function (EPF) User Guide
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===================================================================
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:Author: Frank Li <Frank.Li@nxp.com>
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This document is a guide to help users use pci-epf-vntb function driver
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and ntb_hw_epf host driver for NTB functionality. The list of steps to
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be followed in the host side and EP side is given below. For the hardware
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configuration and internals of NTB using configurable endpoints see
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Documentation/PCI/endpoint/pci-vntb-function.rst
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Endpoint Device
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===============
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Endpoint Controller Devices
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---------------------------
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To find the list of endpoint controller devices in the system::
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# ls /sys/class/pci_epc/
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5f010000.pcie_ep
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If PCI_ENDPOINT_CONFIGFS is enabled::
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# ls /sys/kernel/config/pci_ep/controllers
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5f010000.pcie_ep
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Endpoint Function Drivers
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-------------------------
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To find the list of endpoint function drivers in the system::
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# ls /sys/bus/pci-epf/drivers
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pci_epf_ntb pci_epf_test pci_epf_vntb
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If PCI_ENDPOINT_CONFIGFS is enabled::
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# ls /sys/kernel/config/pci_ep/functions
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pci_epf_ntb pci_epf_test pci_epf_vntb
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Creating pci-epf-vntb Device
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----------------------------
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PCI endpoint function device can be created using the configfs. To create
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pci-epf-vntb device, the following commands can be used::
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# mount -t configfs none /sys/kernel/config
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# cd /sys/kernel/config/pci_ep/
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# mkdir functions/pci_epf_vntb/func1
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The "mkdir func1" above creates the pci-epf-ntb function device that will
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be probed by pci_epf_vntb driver.
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The PCI endpoint framework populates the directory with the following
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configurable fields::
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# ls functions/pci_epf_ntb/func1
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baseclass_code deviceid msi_interrupts pci-epf-ntb.0
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progif_code secondary subsys_id vendorid
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cache_line_size interrupt_pin msix_interrupts primary
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revid subclass_code subsys_vendor_id
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The PCI endpoint function driver populates these entries with default values
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when the device is bound to the driver. The pci-epf-vntb driver populates
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vendorid with 0xffff and interrupt_pin with 0x0001::
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# cat functions/pci_epf_vntb/func1/vendorid
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0xffff
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# cat functions/pci_epf_vntb/func1/interrupt_pin
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0x0001
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Configuring pci-epf-vntb Device
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-------------------------------
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The user can configure the pci-epf-vntb device using its configfs entry. In order
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to change the vendorid and the deviceid, the following
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commands can be used::
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# echo 0x1957 > functions/pci_epf_vntb/func1/vendorid
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# echo 0x0809 > functions/pci_epf_vntb/func1/deviceid
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In order to configure NTB specific attributes, a new sub-directory to func1
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should be created::
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# mkdir functions/pci_epf_vntb/func1/pci_epf_vntb.0/
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The NTB function driver will populate this directory with various attributes
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that can be configured by the user::
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# ls functions/pci_epf_vntb/func1/pci_epf_vntb.0/
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db_count mw1 mw2 mw3 mw4 num_mws
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spad_count
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A sample configuration for NTB function is given below::
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# echo 4 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/db_count
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# echo 128 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/spad_count
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# echo 1 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/num_mws
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# echo 0x100000 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/mw1
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A sample configuration for virtual NTB driver for virutal PCI bus::
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# echo 0x1957 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/vntb_vid
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# echo 0x080A > functions/pci_epf_vntb/func1/pci_epf_vntb.0/vntb_pid
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# echo 0x10 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/vbus_number
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Binding pci-epf-ntb Device to EP Controller
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--------------------------------------------
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NTB function device should be attached to PCI endpoint controllers
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connected to the host.
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# ln -s controllers/5f010000.pcie_ep functions/pci-epf-ntb/func1/primary
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Once the above step is completed, the PCI endpoint controllers are ready to
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establish a link with the host.
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Start the Link
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--------------
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In order for the endpoint device to establish a link with the host, the _start_
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field should be populated with '1'. For NTB, both the PCI endpoint controllers
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should establish link with the host (imx8 don't need this steps)::
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# echo 1 > controllers/5f010000.pcie_ep/start
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RootComplex Device
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==================
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lspci Output at Host side
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-------------------------
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Note that the devices listed here correspond to the values populated in
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"Creating pci-epf-ntb Device" section above::
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# lspci
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00:00.0 PCI bridge: Freescale Semiconductor Inc Device 0000 (rev 01)
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01:00.0 RAM memory: Freescale Semiconductor Inc Device 0809
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Endpoint Device / Virtual PCI bus
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=================================
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lspci Output at EP Side / Virtual PCI bus
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-----------------------------------------
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Note that the devices listed here correspond to the values populated in
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"Creating pci-epf-ntb Device" section above::
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# lspci
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10:00.0 Unassigned class [ffff]: Dawicontrol Computersysteme GmbH Device 1234 (rev ff)
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Using ntb_hw_epf Device
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-----------------------
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The host side software follows the standard NTB software architecture in Linux.
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All the existing client side NTB utilities like NTB Transport Client and NTB
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Netdev, NTB Ping Pong Test Client and NTB Tool Test Client can be used with NTB
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function device.
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For more information on NTB see
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:doc:`Non-Transparent Bridge <../../driver-api/ntb>`

‎MAINTAINERS

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T: git git://github.com/jonmason/ntb.git
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F: drivers/net/ntb_netdev.c
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F: drivers/ntb/
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F: drivers/pci/endpoint/functions/pci-epf-*ntb.c
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F: include/linux/ntb.h
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F: include/linux/ntb_transport.h
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F: tools/testing/selftests/ntb/

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