| Message ID | 20210427205431.23896-2-lizhi.hou@xilinx.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | XRT Alveo driver overview | expand |
On 4/27/21 1:54 PM, Lizhi Hou wrote: > Describe XRT driver architecture and provide basic overview of > Xilinx Alveo platform. > > Signed-off-by: Sonal Santan <sonal.santan@xilinx.com> > Signed-off-by: Max Zhen <max.zhen@xilinx.com> > Signed-off-by: Lizhi Hou <lizhi.hou@xilinx.com> > --- > Documentation/fpga/index.rst | 1 + > Documentation/fpga/xrt.rst | 844 +++++++++++++++++++++++++++++++++++ > 2 files changed, 845 insertions(+) > create mode 100644 Documentation/fpga/xrt.rst > > diff --git a/Documentation/fpga/index.rst b/Documentation/fpga/index.rst > index f80f95667ca2..30134357b70d 100644 > --- a/Documentation/fpga/index.rst > +++ b/Documentation/fpga/index.rst > @@ -8,6 +8,7 @@ fpga > :maxdepth: 1 > > dfl > + xrt > > .. only:: subproject and html > > diff --git a/Documentation/fpga/xrt.rst b/Documentation/fpga/xrt.rst > new file mode 100644 > index 000000000000..c9faad5f18c4 > --- /dev/null > +++ b/Documentation/fpga/xrt.rst > @@ -0,0 +1,844 @@ > +.. SPDX-License-Identifier: GPL-2.0 > + > +================================== > +XRTV2 Linux Kernel Driver Overview > +================================== > + > +Authors: > + > +* Sonal Santan <sonal.santan@xilinx.com> > +* Max Zhen <max.zhen@xilinx.com> > +* Lizhi Hou <lizhi.hou@xilinx.com> > + > +XRTV2 drivers are second generation `XRT <https://github.com/Xilinx/XRT>`_ > +drivers which support `Alveo <https://www.xilinx.com/products/boards-and-kits/alveo.html>`_ > +PCIe platforms from Xilinx. > + > +XRTV2 drivers support *subsystem* style data driven platforms where driver's > +configuration and behavior is determined by meta data provided by the platform > +(in *device tree* format). Primary management physical function (MPF) driver > +is called **xrt-mgnt**. Primary user physical function (UPF) driver is called > +**xrt-user** and is under development. xrt driver framework and HW subsystem > +drivers are packaged into a library module called **xrt-lib**, which is shared > +by **xrt-mgnt** and **xrt-user** (under development). The xrt driver framework > +implements a ``bus_type`` called **xrt_bus_type** which is used to discover HW nice, good to see bus change. This is the only instance. will this be documented fuller later ? > +subsystems and facilitate inter HW subsystem interaction. > + > +Driver Modules > +============== > + > +xrt-lib.ko > +---------- > + > +Repository of all subsystem drivers and pure software modules that can potentially > +be shared between xrt-mgnt and xrt-user. All these drivers are structured as > +**xrt_driver** and are instantiated by xrt-mgnt (or xrt-user under development) > +based on meta data associated with the hardware. The metadata is in the form of a > +device tree as mentioned before. Each xrt driver statically defines a subsystem > +node array by using node name or a string in its ``.endpoints`` property. And this > +array is eventually translated to IOMEM resources in the instantiated xrt device. > + > +The xrt-lib infrastructure provides hooks to xrt drivers for device node > +management, user file operations and ioctl callbacks. The core infrastructure also > +provides bus functionality for xrt driver registration, discovery and inter xrt > +driver leaf calls. > + > +.. note:: > + See code in ``include/xleaf.h`` and ``include/xdevice.h`` > + > + > +xrt-mgnt.ko > +------------ > + > +The xrt-mgnt driver is a PCIe device driver driving MPF found on Xilinx's Alveo > +PCIe device. It consists of one *root* driver, one or more *group* drivers > +and one or more *xleaf* drivers. The root and MPF specific xleaf drivers are > +in xrt-mgnt.ko. The group driver and other xleaf drivers are in xrt-lib.ko. > + > +The instantiation of specific group driver or xleaf driver is completely data > +driven based on meta data (mostly in device tree format) found through VSEC > +capability and inside firmware files, such as platform xsabin or user xclbin file. > +The root driver manages the life cycle of multiple group drivers, which, in turn, > +manages multiple xleaf drivers. This allows a single set of drivers to support > +all kinds of subsystems exposed by different shells. The difference among all > +these subsystems will be handled in xleaf drivers with root and group drivers > +being part of the infrastructure and provide common services for all leaves > +found on all platforms. > + > +The driver object model looks like the following:: > + > + +-----------+ > + | xroot | > + +-----+-----+ > + | > + +-----------+-----------+ > + | | > + v v > + +-----------+ +-----------+ > + | group | ... | group | > + +-----+-----+ +------+----+ > + | | > + | | > + +-----+----+ +-----+----+ > + | | | | > + v v v v > + +-------+ +-------+ +-------+ +-------+ > + | xleaf |..| xleaf | | xleaf |..| xleaf | > + +-------+ +-------+ +-------+ +-------+ > + > +As an example for Xilinx Alveo U50 before user xclbin download, the tree > +looks like the following:: > + > + +-----------+ > + | xrt-mgnt | > + +-----+-----+ > + | > + +-------------------------+--------------------+ > + | | | > + v v v > + +--------+ +--------+ +--------+ > + | group0 | | group1 | | group2 | > + +----+---+ +----+---+ +---+----+ > + | | | > + | | | > + +-----+-----+ +----+-----+---+ +-----+-----+----+--------+ > + | | | | | | | | | > + v v | v v | v v | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | > + | xmgnt_main | | VSEC | | | GPIO | | QSPI | | | CMC | | AXI-GATE0 | | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | > + | +---------+ | +------+ +-----------+ | > + +>| MAILBOX | +->| ICAP | | AXI-GATE1 |<+ > + +---------+ | +------+ +-----------+ > + | +-------+ > + +->| CALIB | > + +-------+ > + > +After an xclbin is downloaded, group3 will be added and the tree looks like the > +following:: > + > + +-----------+ > + | xrt-mgnt | > + +-----+-----+ > + | > + +-------------------------+--------------------+-----------------+ > + | | | | > + v v v | > + +--------+ +--------+ +--------+ | > + | group0 | | group1 | | group2 | | > + +----+---+ +----+---+ +---+----+ | > + | | | | > + | | | | > + +-----+-----+ +-----+-----+---+ +-----+-----+----+--------+ | > + | | | | | | | | | | > + v v | v v | v v | | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | | > + | xmgnt_main | | VSEC | | | GPIO | | QSPI | | | CMC | | AXI-GATE0 | | | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | | > + | +---------+ | +------+ +-----------+ | | > + +>| MAILBOX | +->| ICAP | | AXI-GATE1 |<+ | > + +---------+ | +------+ +-----------+ | > + | +-------+ | > + +->| CALIB | | > + +-------+ | > + +---+----+ | > + | group3 |<--------------------------------------------+ > + +--------+ > + | > + | > + +-------+--------+---+--+--------+------+-------+ > + | | | | | | | > + v | v | v | v > + +--------+ | +--------+ | +--------+ | +-----+ > + | CLOCK0 | | | CLOCK1 | | | CLOCK2 | | | UCS | > + +--------+ v +--------+ v +--------+ v +-----+ > + +-------------+ +-------------+ +-------------+ > + | CLOCK-FREQ0 | | CLOCK-FREQ1 | | CLOCK-FREQ2 | > + +-------------+ +-------------+ +-------------+ > + > + > +root > +^^^^ > + > +The root driver is a PCIe device driver attached to MPF. It's part of the > +infrastructure of the MPF driver and resides in xrt-mgnt.ko. This driver > + > +* manages one or more group drivers > +* provides access to functionalities that requires pci_dev, such as PCIE config > + space access, to other xleaf drivers through root calls > +* facilities event callbacks for other xleaf drivers > +* facilities inter-leaf driver calls for other xleaf drivers > + > +When root driver starts, it will explicitly create an initial group instance, > +which contains xleaf drivers that will trigger the creation of other group > +instances. The root driver will wait for all group and leaves to be created > +before it returns from it's probe routine and claim success of the > +initialization of the entire xrt-mgnt driver. If any leaf fails to initialize > +the xrt-mgnt driver will still come online but with limited functionality. > + > +.. note:: > + See code in ``lib/xroot.c`` and ``mgnt/root.c`` > + > + > +group > +^^^^^ > + > +The group driver represents a pseudo device whose life cycle is managed by > +root and does not have real IO mem or IRQ resources. It's part of the > +infrastructure of the MPF driver and resides in xrt-lib.ko. This driver > + > +* manages one or more xleaf drivers > +* provides access to root from leaves, so that root calls, event notifications > + and inter-leaf calls can happen > + > +In xrt-mgnt, an initial group driver instance will be created by the root. This > +instance contains leaves that will trigger group instances to be created to > +manage groups of leaves found on different partitions on hardware, such as > +VSEC, Shell, and User. > + > +Every *fpga_region* has a group object associated with it. The group is > +created when xclbin image is loaded on the fpga_region. The existing group > +is destroyed when a new xclbin image is loaded. The fpga_region persists > +across xclbin downloads. > + > +.. note:: > + See code in ``lib/group.c`` > + > + > +xleaf > +^^^^^ > + > +The xleaf driver is a xrt device driver whose life cycle is managed by > +a group driver and may or may not have real IO mem or IRQ resources. They > +are the real meat of xrt-mgnt and manage HW subsystems they are attached to. > + ok > +A xleaf driver may not have real hardware resources when it merely acts as a > +driver that manages certain in-memory states for xrt-mgnt. These in-memory > +states could be shared by multiple other leaves. > + > +Leaf drivers assigned to specific hardware resources drive specific subsystem in > +the device. To manipulate the subsystem or carry out a task, a xleaf driver may > +ask help from the root via root calls and/or from other leaves via inter-leaf > +calls. > + > +A xleaf can also broadcast events through infrastructure code for other leaves > +to process. It can also receive event notification from infrastructure about > +certain events, such as post-creation or pre-exit of a particular xleaf. > + > +.. note:: > + See code in ``lib/xleaf/*.c`` > + > + > +FPGA Manager Interaction > +======================== > + > +fpga_manager > +------------ > + > +An instance of fpga_manager is created by xmgnt_main and is used for xclbin > +image download. fpga_manager requires the full xclbin image before it can > +start programming the FPGA configuration engine via Internal Configuration > +Access Port (ICAP) xrt driver. > + > +fpga_region > +----------- > + > +For every interface exposed by the currently loaded xclbin/xsabin in the > +*parent* fpga_region a new instance of fpga_region is created like a *child* > +fpga_region. The device tree of the *parent* fpga_region defines the > +resources for a new instance of fpga_bridge which isolates the parent from > +child fpga_region. This new instance of fpga_bridge will be used when a > +xclbin image is loaded on the child fpga_region. After the xclbin image is > +downloaded to the fpga_region, an instance of group is created for the > +fpga_region using the device tree obtained as part of the xclbin. If this > +device tree defines any child interfaces then it can trigger the creation of > +fpga_bridge and fpga_region for the next region in the chain. > + > +fpga_bridge > +----------- > + > +Like the fpga_region, matching fpga_bridge is also created by walking the > +device tree of the parent group. > + > +Driver Interfaces > +================= > + > +xrt-mgnt Driver Ioctls > +---------------------- > + > +Ioctls exposed by xrt-mgnt driver to user space are enumerated in the following > +table: > + > +== ===================== ============================ ========================== > +# Functionality ioctl request code data format > +== ===================== ============================ ========================== > +1 FPGA image download XMGNT_IOCICAPDOWNLOAD_AXLF xmgnt_ioc_bitstream_axlf > +== ===================== ============================ ========================== > + > +A user xclbin can be downloaded by using the xbmgmt tool from the XRT open source > +suite. See example usage below:: > + > + xbmgmt partition --program --path /lib/firmware/xilinx/862c7020a250293e32036f19956669e5/test/verify.xclbin --force > + > +xrt-mgnt Driver Sysfs > +---------------------- > + > +xrt-mgnt driver exposes a rich set of sysfs interfaces. Subsystem xrt > +drivers export sysfs node for every platform instance. > + > +Every partition also exports its UUIDs. See below for examples:: > + > + /sys/bus/pci/devices/0000:06:00.0/xmgnt_main.0/interface_uuids > + /sys/bus/pci/devices/0000:06:00.0/xmgnt_main.0/logic_uuids > + > + > +hwmon > +----- > + > +xmgnt driver exposes standard hwmon interface to report voltage, current, The xrt-mgmt > +temperature, power, etc. These can easily be viewed using *sensors* command > +line utility. > + > +Alveo Platform Overview > +======================= > + > +Alveo platforms are architected as two physical FPGA partitions: *Shell* and > +*User*. The Shell provides basic infrastructure for the Alveo platform like > +PCIe connectivity, board management, Dynamic Function Exchange (DFX), sensors, > +clocking, reset, and security. User partition contains user compiled FPGA From v4, 'User' needs the article 'The' , so change to 'The User' in both use of user, so also need a change of 'user' to 'the user' > +binary which is loaded by a process called DFX also known as partial > +reconfiguration. > + > +For DFX to work properly physical partitions require strict HW compatibility > +with each other. Every physical partition has two interface UUIDs: *parent* UUID > +and *child* UUID. For simple single stage platforms, Shell → User forms parent > +child relationship. > + > +.. note:: > + Partition compatibility matching is key design component of Alveo platforms From v4, the article 'a' needs to preceed key. change 'is key' to 'is a key' > + and XRT. Partitions have child and parent relationship. A loaded partition > + exposes child partition UUID to advertise its compatibility requirement.When From v4. A space must follow a '.' so change 'requirement.When' to requirement. When' > + loading a child partition the xrt-mgnt management driver matches parent UUID of > + the child partition against child UUID exported by the parent. Parent and > + child partition UUIDs are stored in the *xclbin* (for user) or *xsabin* (for > + shell). Except for root UUID exported by VSEC, hardware itself does not know > + about UUIDs. UUIDs are stored in xsabin and xclbin. The image format has a > + special node called Partition UUIDs which define the compatibility UUIDs. See > + :ref:`partition_uuids`. > + > + > +The physical partitions and their loading is illustrated below:: > + > + SHELL USER > + +-----------+ +-------------------+ > + | | | | > + | VSEC UUID | CHILD PARENT | LOGIC UUID | > + | o------->|<--------o | > + | | UUID UUID | | > + +-----+-----+ +--------+----------+ > + | | > + . . > + | | > + +---+---+ +------+--------+ > + | POR | | USER COMPILED | > + | FLASH | | XCLBIN | > + +-------+ +---------------+ > + > + > +Loading Sequence > +---------------- > + > +The Shell partition is loaded from flash at system boot time. It establishes the > +PCIe link and exposes two physical functions to the BIOS. After the OS boots, xrt-mgnt Please review the v4 comments for additions of 'the' and 'a' and comments above. I will look for them again in v6 > +driver attaches to the PCIe physical function 0 exposed by the Shell and then looks > +for VSEC in PCIe extended configuration space. Using VSEC it determines the logic > +UUID of Shell and uses the UUID to load matching *xsabin* file from Linux firmware > +directory. The xsabin file contains metadata to discover peripherals that are part > +of Shell and firmware(s) for any embedded soft processors in Shell. The xsabin file > +also contains Partition UUIDs as described here :ref:`partition_uuids`. > + > +The Shell exports a child interface UUID which is used for the compatibility check > +when loading user compiled xclbin over the User partition as part of DFX. When a user > +requests loading of a specific xclbin the xrt-mgnt management driver reads the parent From v4, need a ',' to separate clauses. From v4, drop 'management' Tom > +interface UUID specified in the xclbin and matches it with child interface UUID > +exported by Shell to determine if xclbin is compatible with the Shell. If match > +fails loading of xclbin is denied. > + > +xclbin loading is requested using ICAP_DOWNLOAD_AXLF ioctl command. When loading > +xclbin, xrt-mgnt driver performs the following *logical* operations: > + > +1. Copy xclbin from user to kernel memory > +2. Sanity check the xclbin contents > +3. Isolate the User partition > +4. Download the bitstream using the FPGA config engine (ICAP) > +5. De-isolate the User partition > +6. Program the clocks (ClockWiz) driving the User partition > +7. Wait for memory controller (MIG) calibration > +8. Return the loading status back to the caller > + > +`Platform Loading Overview <https://xilinx.github.io/XRT/master/html/platforms_partitions.html>`_ > +provides more detailed information on platform loading. > + > + > +xsabin > +------ > + > +Each Alveo platform comes packaged with its own xsabin. The xsabin is a trusted > +component of the platform. For format details refer to :ref:`xsabin_xclbin_container_format` > +below. xsabin contains basic information like UUIDs, platform name and metadata in the > +form of device tree. See :ref:`device_tree_usage` below for details and example. > + > +xclbin > +------ > + > +xclbin is compiled by end user using > +`Vitis <https://www.xilinx.com/products/design-tools/vitis/vitis-platform.html>`_ > +tool set from Xilinx. The xclbin contains sections describing user compiled > +acceleration engines/kernels, memory subsystems, clocking information etc. It also > +contains FPGA bitstream for the user partition, UUIDs, platform name, etc. > + > + > +.. _xsabin_xclbin_container_format: > + > +xsabin/xclbin Container Format > +------------------------------ > + > +xclbin/xsabin is ELF-like binary container format. It is structured as series of > +sections. There is a file header followed by several section headers which is > +followed by sections. A section header points to an actual section. There is an > +optional signature at the end. The format is defined by header file ``xclbin.h``. > +The following figure illustrates a typical xclbin:: > + > + > + +---------------------+ > + | | > + | HEADER | > + +---------------------+ > + | SECTION HEADER | > + | | > + +---------------------+ > + | ... | > + | | > + +---------------------+ > + | SECTION HEADER | > + | | > + +---------------------+ > + | SECTION | > + | | > + +---------------------+ > + | ... | > + | | > + +---------------------+ > + | SECTION | > + | | > + +---------------------+ > + | SIGNATURE | > + | (OPTIONAL) | > + +---------------------+ > + > + > +xclbin/xsabin files can be packaged, un-packaged and inspected using XRT utility > +called **xclbinutil**. xclbinutil is part of XRT open source software stack. The > +source code for xclbinutil can be found at > +https://github.com/Xilinx/XRT/tree/master/src/runtime_src/tools/xclbinutil > + > +For example to enumerate the contents of a xclbin/xsabin use the *--info* switch > +as shown below:: > + > + > + xclbinutil --info --input /opt/xilinx/firmware/u50/gen3x16-xdma/blp/test/bandwidth.xclbin > + xclbinutil --info --input /lib/firmware/xilinx/862c7020a250293e32036f19956669e5/partition.xsabin > + > + > +.. _device_tree_usage: > + > +Device Tree Usage > +----------------- > + > +As mentioned previously xsabin file stores metadata which advertise HW subsystems present > +in a partition. The metadata is stored in device tree format with a well defined schema. > +XRT management driver uses this information to bind *xrt drivers* to the subsystem > +instantiations. The xrt drivers are found in **xrt-lib.ko** kernel module defined > +earlier. > + > +Logic UUID > +^^^^^^^^^^ > +A partition is identified uniquely through ``logic_uuid`` property:: > + > + /dts-v1/; > + / { > + logic_uuid = "0123456789abcdef0123456789abcdef"; > + ... > + } > + > +Schema Version > +^^^^^^^^^^^^^^ > +Schema version is defined through ``schema_version`` node. And it contains ``major`` > +and ``minor`` properties as below:: > + > + /dts-v1/; > + / { > + schema_version { > + major = <0x01>; > + minor = <0x00>; > + }; > + ... > + } > + > +.. _partition_uuids: > + > +Partition UUIDs > +^^^^^^^^^^^^^^^ > +As mentioned earlier, each partition may have parent and child UUIDs. These UUIDs are > +defined by ``interfaces`` node and ``interface_uuid`` property:: > + > + /dts-v1/; > + / { > + interfaces { > + @0 { > + interface_uuid = "0123456789abcdef0123456789abcdef"; > + }; > + @1 { > + interface_uuid = "fedcba9876543210fedcba9876543210"; > + }; > + ... > + }; > + ... > + } > + > + > +Subsystem Instantiations > +^^^^^^^^^^^^^^^^^^^^^^^^ > +Subsystem instantiations are captured as children of ``addressable_endpoints`` > +node:: > + > + /dts-v1/; > + / { > + addressable_endpoints { > + abc { > + ... > + }; > + def { > + ... > + }; > + ... > + } > + } > + > +Subnode 'abc' and 'def' are the name of subsystem nodes > + > +Subsystem Node > +^^^^^^^^^^^^^^ > +Each subsystem node and its properties define a hardware instance:: > + > + > + addressable_endpoints { > + abc { > + reg = <0xa 0xb> > + pcie_physical_function = <0x0>; > + pcie_bar_mapping = <0x2>; > + compatible = "abc def"; > + firmware { > + firmware_product_name = "abc" > + firmware_branch_name = "def" > + firmware_version_major = <1> > + firmware_version_minor = <2> > + }; > + } > + ... > + } > + > +:reg: > + Property defines address range. '<0xa 0xb>' is BAR offset and length pair, both > + are 64-bit integer. > +:pcie_physical_function: > + Property specifies which PCIe physical function the subsystem node resides. > +:pcie_bar_mapping: > + Property specifies which PCIe BAR the subsystem node resides. '<0x2>' is BAR > + index and it is 0 if this property is not defined. > +:compatible: > + Property is a list of strings. The first string in the list specifies the exact > + subsystem node. The following strings represent other devices that the device > + is compatible with. > +:firmware: > + Subnode defines the firmware required by this subsystem node. > + > +Alveo U50 Platform Example > +^^^^^^^^^^^^^^^^^^^^^^^^^^ > +:: > + > + /dts-v1/; > + > + /{ > + logic_uuid = "f465b0a3ae8c64f619bc150384ace69b"; > + > + schema_version { > + major = <0x01>; > + minor = <0x00>; > + }; > + > + interfaces { > + > + @0 { > + interface_uuid = "862c7020a250293e32036f19956669e5"; > + }; > + }; > + > + addressable_endpoints { > + > + ep_blp_rom_00 { > + reg = <0x00 0x1f04000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + }; > + > + ep_card_flash_program_00 { > + reg = <0x00 0x1f06000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_quad_spi-1.0\0axi_quad_spi"; > + interrupts = <0x03 0x03>; > + }; > + > + ep_cmc_firmware_mem_00 { > + reg = <0x00 0x1e20000 0x00 0x20000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + > + firmware { > + firmware_product_name = "cmc"; > + firmware_branch_name = "u50"; > + firmware_version_major = <0x01>; > + firmware_version_minor = <0x00>; > + }; > + }; > + > + ep_cmc_intc_00 { > + reg = <0x00 0x1e03000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_intc-1.0\0axi_intc"; > + interrupts = <0x04 0x04>; > + }; > + > + ep_cmc_mutex_00 { > + reg = <0x00 0x1e02000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_cmc_regmap_00 { > + reg = <0x00 0x1e08000 0x00 0x2000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + > + firmware { > + firmware_product_name = "sc-fw"; > + firmware_branch_name = "u50"; > + firmware_version_major = <0x05>; > + }; > + }; > + > + ep_cmc_reset_00 { > + reg = <0x00 0x1e01000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_ddr_mem_calib_00 { > + reg = <0x00 0x63000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_debug_bscan_mgmt_00 { > + reg = <0x00 0x1e90000 0x00 0x10000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-debug_bridge-1.0\0debug_bridge"; > + }; > + > + ep_ert_base_address_00 { > + reg = <0x00 0x21000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_ert_command_queue_mgmt_00 { > + reg = <0x00 0x40000 0x00 0x10000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-ert_command_queue-1.0\0ert_command_queue"; > + }; > + > + ep_ert_command_queue_user_00 { > + reg = <0x00 0x40000 0x00 0x10000>; > + pcie_physical_function = <0x01>; > + compatible = "xilinx.com,reg_abs-ert_command_queue-1.0\0ert_command_queue"; > + }; > + > + ep_ert_firmware_mem_00 { > + reg = <0x00 0x30000 0x00 0x8000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + > + firmware { > + firmware_product_name = "ert"; > + firmware_branch_name = "v20"; > + firmware_version_major = <0x01>; > + }; > + }; > + > + ep_ert_intc_00 { > + reg = <0x00 0x23000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_intc-1.0\0axi_intc"; > + interrupts = <0x05 0x05>; > + }; > + > + ep_ert_reset_00 { > + reg = <0x00 0x22000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_ert_sched_00 { > + reg = <0x00 0x50000 0x00 0x1000>; > + pcie_physical_function = <0x01>; > + compatible = "xilinx.com,reg_abs-ert_sched-1.0\0ert_sched"; > + interrupts = <0x09 0x0c>; > + }; > + > + ep_fpga_configuration_00 { > + reg = <0x00 0x1e88000 0x00 0x8000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_hwicap-1.0\0axi_hwicap"; > + interrupts = <0x02 0x02>; > + }; > + > + ep_icap_reset_00 { > + reg = <0x00 0x1f07000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_msix_00 { > + reg = <0x00 0x00 0x00 0x20000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-msix-1.0\0msix"; > + pcie_bar_mapping = <0x02>; > + }; > + > + ep_pcie_link_mon_00 { > + reg = <0x00 0x1f05000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_pr_isolate_plp_00 { > + reg = <0x00 0x1f01000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_pr_isolate_ulp_00 { > + reg = <0x00 0x1000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_uuid_rom_00 { > + reg = <0x00 0x64000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + }; > + > + ep_xdma_00 { > + reg = <0x00 0x00 0x00 0x10000>; > + pcie_physical_function = <0x01>; > + compatible = "xilinx.com,reg_abs-xdma-1.0\0xdma"; > + pcie_bar_mapping = <0x02>; > + }; > + }; > + > + } > + > + > + > +Deployment Models > +================= > + > +Baremetal > +--------- > + > +In bare-metal deployments, both MPF and UPF are visible and accessible. xrt-mgnt > +driver binds to MPF. xrt-mgnt driver operations are privileged and available to > +system administrator. The full stack is illustrated below:: > + > + HOST > + > + [XRT-MGNT] [XRT-USER] > + | | > + | | > + +-----+ +-----+ > + | MPF | | UPF | > + | | | | > + | PF0 | | PF1 | > + +--+--+ +--+--+ > + ......... ^................. ^.......... > + | | > + | PCIe DEVICE | > + | | > + +--+------------------+--+ > + | SHELL | > + | | > + +------------------------+ > + | USER | > + | | > + | | > + | | > + | | > + +------------------------+ > + > + > + > +Virtualized > +----------- > + > +In virtualized deployments, privileged MPF is assigned to host but unprivileged > +UPF is assigned to guest VM via PCIe pass-through. xrt-mgnt driver in host binds > +to MPF. xrt-mgnt driver operations are privileged and only accessible to the MPF. > +The full stack is illustrated below:: > + > + > + .............. > + HOST . VM . > + . . > + [XRT-MGNT] . [XRT-USER] . > + | . | . > + | . | . > + +-----+ . +-----+ . > + | MPF | . | UPF | . > + | | . | | . > + | PF0 | . | PF1 | . > + +--+--+ . +--+--+ . > + ......... ^................. ^.......... > + | | > + | PCIe DEVICE | > + | | > + +--+------------------+--+ > + | SHELL | > + | | > + +------------------------+ > + | USER | > + | | > + | | > + | | > + | | > + +------------------------+ > + > + > + > + > + > +Platform Security Considerations > +================================ > + > +`Security of Alveo Platform <https://xilinx.github.io/XRT/master/html/security.html>`_ > +discusses the deployment options and security implications in great detail.
Hi Lizhi, nothing major, couple of nits inline. On Tue, Apr 27, 2021 at 01:54:12PM -0700, Lizhi Hou wrote: > Describe XRT driver architecture and provide basic overview of > Xilinx Alveo platform. > > Signed-off-by: Sonal Santan <sonal.santan@xilinx.com> > Signed-off-by: Max Zhen <max.zhen@xilinx.com> > Signed-off-by: Lizhi Hou <lizhi.hou@xilinx.com> > --- > Documentation/fpga/index.rst | 1 + > Documentation/fpga/xrt.rst | 844 +++++++++++++++++++++++++++++++++++ > 2 files changed, 845 insertions(+) > create mode 100644 Documentation/fpga/xrt.rst > > diff --git a/Documentation/fpga/index.rst b/Documentation/fpga/index.rst > index f80f95667ca2..30134357b70d 100644 > --- a/Documentation/fpga/index.rst > +++ b/Documentation/fpga/index.rst > @@ -8,6 +8,7 @@ fpga > :maxdepth: 1 > > dfl > + xrt > > .. only:: subproject and html > > diff --git a/Documentation/fpga/xrt.rst b/Documentation/fpga/xrt.rst > new file mode 100644 > index 000000000000..c9faad5f18c4 > --- /dev/null > +++ b/Documentation/fpga/xrt.rst > @@ -0,0 +1,844 @@ > +.. SPDX-License-Identifier: GPL-2.0 > + > +================================== > +XRTV2 Linux Kernel Driver Overview > +================================== > + > +Authors: > + > +* Sonal Santan <sonal.santan@xilinx.com> > +* Max Zhen <max.zhen@xilinx.com> > +* Lizhi Hou <lizhi.hou@xilinx.com> > + > +XRTV2 drivers are second generation `XRT <https://github.com/Xilinx/XRT>`_ > +drivers which support `Alveo <https://www.xilinx.com/products/boards-and-kits/alveo.html>`_ > +PCIe platforms from Xilinx. > + > +XRTV2 drivers support *subsystem* style data driven platforms where driver's > +configuration and behavior is determined by meta data provided by the platform > +(in *device tree* format). Primary management physical function (MPF) driver > +is called **xrt-mgnt**. Primary user physical function (UPF) driver is called > +**xrt-user** and is under development. xrt driver framework and HW subsystem > +drivers are packaged into a library module called **xrt-lib**, which is shared > +by **xrt-mgnt** and **xrt-user** (under development). The xrt driver framework > +implements a ``bus_type`` called **xrt_bus_type** which is used to discover HW > +subsystems and facilitate inter HW subsystem interaction. > + > +Driver Modules > +============== > + > +xrt-lib.ko > +---------- > + > +Repository of all subsystem drivers and pure software modules that can potentially > +be shared between xrt-mgnt and xrt-user. All these drivers are structured as > +**xrt_driver** and are instantiated by xrt-mgnt (or xrt-user under development) > +based on meta data associated with the hardware. The metadata is in the form of a > +device tree as mentioned before. Each xrt driver statically defines a subsystem > +node array by using node name or a string in its ``.endpoints`` property. And this > +array is eventually translated to IOMEM resources in the instantiated xrt device. > + > +The xrt-lib infrastructure provides hooks to xrt drivers for device node > +management, user file operations and ioctl callbacks. The core infrastructure also > +provides bus functionality for xrt driver registration, discovery and inter xrt > +driver leaf calls. > + > +.. note:: > + See code in ``include/xleaf.h`` and ``include/xdevice.h`` > + > + > +xrt-mgnt.ko Nit: Don't people usually use 'mgmt' instead of 'mgnt'? > +------------ > + > +The xrt-mgnt driver is a PCIe device driver driving MPF found on Xilinx's Alveo > +PCIe device. It consists of one *root* driver, one or more *group* drivers > +and one or more *xleaf* drivers. The root and MPF specific xleaf drivers are > +in xrt-mgnt.ko. The group driver and other xleaf drivers are in xrt-lib.ko. > + > +The instantiation of specific group driver or xleaf driver is completely data > +driven based on meta data (mostly in device tree format) found through VSEC > +capability and inside firmware files, such as platform xsabin or user xclbin file. > +The root driver manages the life cycle of multiple group drivers, which, in turn, > +manages multiple xleaf drivers. This allows a single set of drivers to support > +all kinds of subsystems exposed by different shells. The difference among all > +these subsystems will be handled in xleaf drivers with root and group drivers > +being part of the infrastructure and provide common services for all leaves > +found on all platforms. > + > +The driver object model looks like the following:: > + > + +-----------+ > + | xroot | > + +-----+-----+ > + | > + +-----------+-----------+ > + | | > + v v > + +-----------+ +-----------+ > + | group | ... | group | > + +-----+-----+ +------+----+ > + | | > + | | > + +-----+----+ +-----+----+ > + | | | | > + v v v v > + +-------+ +-------+ +-------+ +-------+ > + | xleaf |..| xleaf | | xleaf |..| xleaf | > + +-------+ +-------+ +-------+ +-------+ > + > +As an example for Xilinx Alveo U50 before user xclbin download, the tree > +looks like the following:: > + > + +-----------+ > + | xrt-mgnt | > + +-----+-----+ > + | > + +-------------------------+--------------------+ > + | | | > + v v v > + +--------+ +--------+ +--------+ > + | group0 | | group1 | | group2 | > + +----+---+ +----+---+ +---+----+ > + | | | > + | | | > + +-----+-----+ +----+-----+---+ +-----+-----+----+--------+ > + | | | | | | | | | > + v v | v v | v v | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | > + | xmgnt_main | | VSEC | | | GPIO | | QSPI | | | CMC | | AXI-GATE0 | | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | > + | +---------+ | +------+ +-----------+ | > + +>| MAILBOX | +->| ICAP | | AXI-GATE1 |<+ > + +---------+ | +------+ +-----------+ > + | +-------+ > + +->| CALIB | > + +-------+ > + > +After an xclbin is downloaded, group3 will be added and the tree looks like the > +following:: > + > + +-----------+ > + | xrt-mgnt | > + +-----+-----+ > + | > + +-------------------------+--------------------+-----------------+ > + | | | | > + v v v | > + +--------+ +--------+ +--------+ | > + | group0 | | group1 | | group2 | | > + +----+---+ +----+---+ +---+----+ | > + | | | | > + | | | | > + +-----+-----+ +-----+-----+---+ +-----+-----+----+--------+ | > + | | | | | | | | | | > + v v | v v | v v | | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | | > + | xmgnt_main | | VSEC | | | GPIO | | QSPI | | | CMC | | AXI-GATE0 | | | > + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | | > + | +---------+ | +------+ +-----------+ | | > + +>| MAILBOX | +->| ICAP | | AXI-GATE1 |<+ | > + +---------+ | +------+ +-----------+ | > + | +-------+ | > + +->| CALIB | | > + +-------+ | > + +---+----+ | > + | group3 |<--------------------------------------------+ > + +--------+ > + | > + | > + +-------+--------+---+--+--------+------+-------+ > + | | | | | | | > + v | v | v | v > + +--------+ | +--------+ | +--------+ | +-----+ > + | CLOCK0 | | | CLOCK1 | | | CLOCK2 | | | UCS | > + +--------+ v +--------+ v +--------+ v +-----+ > + +-------------+ +-------------+ +-------------+ > + | CLOCK-FREQ0 | | CLOCK-FREQ1 | | CLOCK-FREQ2 | > + +-------------+ +-------------+ +-------------+ > + > + > +root > +^^^^ > + > +The root driver is a PCIe device driver attached to MPF. It's part of the > +infrastructure of the MPF driver and resides in xrt-mgnt.ko. This driver > + > +* manages one or more group drivers > +* provides access to functionalities that requires pci_dev, such as PCIE config > + space access, to other xleaf drivers through root calls > +* facilities event callbacks for other xleaf drivers > +* facilities inter-leaf driver calls for other xleaf drivers > + > +When root driver starts, it will explicitly create an initial group instance, > +which contains xleaf drivers that will trigger the creation of other group > +instances. The root driver will wait for all group and leaves to be created > +before it returns from it's probe routine and claim success of the > +initialization of the entire xrt-mgnt driver. If any leaf fails to initialize > +the xrt-mgnt driver will still come online but with limited functionality. > + > +.. note:: > + See code in ``lib/xroot.c`` and ``mgnt/root.c`` > + > + > +group > +^^^^^ > + > +The group driver represents a pseudo device whose life cycle is managed by > +root and does not have real IO mem or IRQ resources. It's part of the > +infrastructure of the MPF driver and resides in xrt-lib.ko. This driver > + > +* manages one or more xleaf drivers > +* provides access to root from leaves, so that root calls, event notifications > + and inter-leaf calls can happen > + > +In xrt-mgnt, an initial group driver instance will be created by the root. This > +instance contains leaves that will trigger group instances to be created to > +manage groups of leaves found on different partitions on hardware, such as > +VSEC, Shell, and User. > + > +Every *fpga_region* has a group object associated with it. The group is > +created when xclbin image is loaded on the fpga_region. The existing group > +is destroyed when a new xclbin image is loaded. The fpga_region persists > +across xclbin downloads. > + > +.. note:: > + See code in ``lib/group.c`` > + > + > +xleaf > +^^^^^ > + > +The xleaf driver is a xrt device driver whose life cycle is managed by > +a group driver and may or may not have real IO mem or IRQ resources. They > +are the real meat of xrt-mgnt and manage HW subsystems they are attached to. > + > +A xleaf driver may not have real hardware resources when it merely acts as a > +driver that manages certain in-memory states for xrt-mgnt. These in-memory > +states could be shared by multiple other leaves. > + > +Leaf drivers assigned to specific hardware resources drive specific subsystem in > +the device. To manipulate the subsystem or carry out a task, a xleaf driver may > +ask help from the root via root calls and/or from other leaves via inter-leaf > +calls. > + > +A xleaf can also broadcast events through infrastructure code for other leaves > +to process. It can also receive event notification from infrastructure about > +certain events, such as post-creation or pre-exit of a particular xleaf. > + > +.. note:: > + See code in ``lib/xleaf/*.c`` > + > + > +FPGA Manager Interaction > +======================== > + > +fpga_manager > +------------ > + > +An instance of fpga_manager is created by xmgnt_main and is used for xclbin > +image download. fpga_manager requires the full xclbin image before it can > +start programming the FPGA configuration engine via Internal Configuration > +Access Port (ICAP) xrt driver. > + > +fpga_region > +----------- > + > +For every interface exposed by the currently loaded xclbin/xsabin in the > +*parent* fpga_region a new instance of fpga_region is created like a *child* > +fpga_region. The device tree of the *parent* fpga_region defines the > +resources for a new instance of fpga_bridge which isolates the parent from > +child fpga_region. This new instance of fpga_bridge will be used when a > +xclbin image is loaded on the child fpga_region. After the xclbin image is > +downloaded to the fpga_region, an instance of group is created for the > +fpga_region using the device tree obtained as part of the xclbin. If this > +device tree defines any child interfaces then it can trigger the creation of > +fpga_bridge and fpga_region for the next region in the chain. > + > +fpga_bridge > +----------- > + > +Like the fpga_region, matching fpga_bridge is also created by walking the > +device tree of the parent group. > + > +Driver Interfaces > +================= > + > +xrt-mgnt Driver Ioctls > +---------------------- > + > +Ioctls exposed by xrt-mgnt driver to user space are enumerated in the following > +table: > + > +== ===================== ============================ ========================== > +# Functionality ioctl request code data format > +== ===================== ============================ ========================== > +1 FPGA image download XMGNT_IOCICAPDOWNLOAD_AXLF xmgnt_ioc_bitstream_axlf > +== ===================== ============================ ========================== > + > +A user xclbin can be downloaded by using the xbmgmt tool from the XRT open source > +suite. See example usage below:: > + > + xbmgmt partition --program --path /lib/firmware/xilinx/862c7020a250293e32036f19956669e5/test/verify.xclbin --force > + > +xrt-mgnt Driver Sysfs > +---------------------- > + > +xrt-mgnt driver exposes a rich set of sysfs interfaces. Subsystem xrt > +drivers export sysfs node for every platform instance. > + > +Every partition also exports its UUIDs. See below for examples:: > + > + /sys/bus/pci/devices/0000:06:00.0/xmgnt_main.0/interface_uuids > + /sys/bus/pci/devices/0000:06:00.0/xmgnt_main.0/logic_uuids > + > + > +hwmon > +----- > + > +xmgnt driver exposes standard hwmon interface to report voltage, current, > +temperature, power, etc. These can easily be viewed using *sensors* command > +line utility. Is this part of the first commit? If not add it when it gets added. > + > +Alveo Platform Overview > +======================= > + > +Alveo platforms are architected as two physical FPGA partitions: *Shell* and > +*User*. The Shell provides basic infrastructure for the Alveo platform like > +PCIe connectivity, board management, Dynamic Function Exchange (DFX), sensors, > +clocking, reset, and security. User partition contains user compiled FPGA > +binary which is loaded by a process called DFX also known as partial > +reconfiguration. > + > +For DFX to work properly physical partitions require strict HW compatibility > +with each other. Every physical partition has two interface UUIDs: *parent* UUID > +and *child* UUID. For simple single stage platforms, Shell → User forms parent > +child relationship. > + > +.. note:: > + Partition compatibility matching is key design component of Alveo platforms > + and XRT. Partitions have child and parent relationship. A loaded partition > + exposes child partition UUID to advertise its compatibility requirement.When > + loading a child partition the xrt-mgnt management driver matches parent UUID of > + the child partition against child UUID exported by the parent. Parent and > + child partition UUIDs are stored in the *xclbin* (for user) or *xsabin* (for > + shell). Except for root UUID exported by VSEC, hardware itself does not know > + about UUIDs. UUIDs are stored in xsabin and xclbin. The image format has a > + special node called Partition UUIDs which define the compatibility UUIDs. See > + :ref:`partition_uuids`. > + > + > +The physical partitions and their loading is illustrated below:: > + > + SHELL USER > + +-----------+ +-------------------+ > + | | | | > + | VSEC UUID | CHILD PARENT | LOGIC UUID | > + | o------->|<--------o | > + | | UUID UUID | | > + +-----+-----+ +--------+----------+ > + | | > + . . > + | | > + +---+---+ +------+--------+ > + | POR | | USER COMPILED | > + | FLASH | | XCLBIN | > + +-------+ +---------------+ > + > + > +Loading Sequence > +---------------- > + > +The Shell partition is loaded from flash at system boot time. It establishes the > +PCIe link and exposes two physical functions to the BIOS. After the OS boots, xrt-mgnt > +driver attaches to the PCIe physical function 0 exposed by the Shell and then looks > +for VSEC in PCIe extended configuration space. Using VSEC it determines the logic > +UUID of Shell and uses the UUID to load matching *xsabin* file from Linux firmware > +directory. The xsabin file contains metadata to discover peripherals that are part > +of Shell and firmware(s) for any embedded soft processors in Shell. The xsabin file > +also contains Partition UUIDs as described here :ref:`partition_uuids`. > + > +The Shell exports a child interface UUID which is used for the compatibility check > +when loading user compiled xclbin over the User partition as part of DFX. When a user > +requests loading of a specific xclbin the xrt-mgnt management driver reads the parent > +interface UUID specified in the xclbin and matches it with child interface UUID > +exported by Shell to determine if xclbin is compatible with the Shell. If match > +fails loading of xclbin is denied. > + > +xclbin loading is requested using ICAP_DOWNLOAD_AXLF ioctl command. When loading > +xclbin, xrt-mgnt driver performs the following *logical* operations: > + > +1. Copy xclbin from user to kernel memory > +2. Sanity check the xclbin contents > +3. Isolate the User partition > +4. Download the bitstream using the FPGA config engine (ICAP) > +5. De-isolate the User partition > +6. Program the clocks (ClockWiz) driving the User partition > +7. Wait for memory controller (MIG) calibration > +8. Return the loading status back to the caller > + > +`Platform Loading Overview <https://xilinx.github.io/XRT/master/html/platforms_partitions.html>`_ > +provides more detailed information on platform loading. > + > + > +xsabin > +------ > + > +Each Alveo platform comes packaged with its own xsabin. The xsabin is a trusted > +component of the platform. For format details refer to :ref:`xsabin_xclbin_container_format` > +below. xsabin contains basic information like UUIDs, platform name and metadata in the > +form of device tree. See :ref:`device_tree_usage` below for details and example. > + > +xclbin > +------ > + > +xclbin is compiled by end user using > +`Vitis <https://www.xilinx.com/products/design-tools/vitis/vitis-platform.html>`_ > +tool set from Xilinx. The xclbin contains sections describing user compiled > +acceleration engines/kernels, memory subsystems, clocking information etc. It also > +contains FPGA bitstream for the user partition, UUIDs, platform name, etc. > + > + > +.. _xsabin_xclbin_container_format: > + > +xsabin/xclbin Container Format > +------------------------------ > + > +xclbin/xsabin is ELF-like binary container format. It is structured as series of > +sections. There is a file header followed by several section headers which is > +followed by sections. A section header points to an actual section. There is an > +optional signature at the end. The format is defined by header file ``xclbin.h``. > +The following figure illustrates a typical xclbin:: > + > + > + +---------------------+ > + | | > + | HEADER | > + +---------------------+ > + | SECTION HEADER | > + | | > + +---------------------+ > + | ... | > + | | > + +---------------------+ > + | SECTION HEADER | > + | | > + +---------------------+ > + | SECTION | > + | | > + +---------------------+ > + | ... | > + | | > + +---------------------+ > + | SECTION | > + | | > + +---------------------+ > + | SIGNATURE | > + | (OPTIONAL) | > + +---------------------+ > + > + > +xclbin/xsabin files can be packaged, un-packaged and inspected using XRT utility > +called **xclbinutil**. xclbinutil is part of XRT open source software stack. The > +source code for xclbinutil can be found at > +https://github.com/Xilinx/XRT/tree/master/src/runtime_src/tools/xclbinutil > + > +For example to enumerate the contents of a xclbin/xsabin use the *--info* switch > +as shown below:: > + > + > + xclbinutil --info --input /opt/xilinx/firmware/u50/gen3x16-xdma/blp/test/bandwidth.xclbin > + xclbinutil --info --input /lib/firmware/xilinx/862c7020a250293e32036f19956669e5/partition.xsabin > + > + > +.. _device_tree_usage: > + > +Device Tree Usage > +----------------- > + > +As mentioned previously xsabin file stores metadata which advertise HW subsystems present > +in a partition. The metadata is stored in device tree format with a well defined schema. > +XRT management driver uses this information to bind *xrt drivers* to the subsystem > +instantiations. The xrt drivers are found in **xrt-lib.ko** kernel module defined > +earlier. > + > +Logic UUID > +^^^^^^^^^^ > +A partition is identified uniquely through ``logic_uuid`` property:: > + > + /dts-v1/; > + / { > + logic_uuid = "0123456789abcdef0123456789abcdef"; > + ... > + } > + > +Schema Version > +^^^^^^^^^^^^^^ > +Schema version is defined through ``schema_version`` node. And it contains ``major`` > +and ``minor`` properties as below:: > + > + /dts-v1/; > + / { > + schema_version { > + major = <0x01>; > + minor = <0x00>; > + }; > + ... > + } > + > +.. _partition_uuids: > + > +Partition UUIDs > +^^^^^^^^^^^^^^^ > +As mentioned earlier, each partition may have parent and child UUIDs. These UUIDs are > +defined by ``interfaces`` node and ``interface_uuid`` property:: > + > + /dts-v1/; > + / { > + interfaces { > + @0 { > + interface_uuid = "0123456789abcdef0123456789abcdef"; > + }; > + @1 { > + interface_uuid = "fedcba9876543210fedcba9876543210"; > + }; > + ... > + }; > + ... > + } > + > + > +Subsystem Instantiations > +^^^^^^^^^^^^^^^^^^^^^^^^ > +Subsystem instantiations are captured as children of ``addressable_endpoints`` > +node:: > + > + /dts-v1/; > + / { > + addressable_endpoints { > + abc { > + ... > + }; > + def { > + ... > + }; > + ... > + } > + } > + > +Subnode 'abc' and 'def' are the name of subsystem nodes > + > +Subsystem Node > +^^^^^^^^^^^^^^ > +Each subsystem node and its properties define a hardware instance:: > + > + > + addressable_endpoints { > + abc { > + reg = <0xa 0xb> > + pcie_physical_function = <0x0>; > + pcie_bar_mapping = <0x2>; > + compatible = "abc def"; > + firmware { > + firmware_product_name = "abc" > + firmware_branch_name = "def" > + firmware_version_major = <1> > + firmware_version_minor = <2> > + }; > + } > + ... > + } > + > +:reg: > + Property defines address range. '<0xa 0xb>' is BAR offset and length pair, both > + are 64-bit integer. > +:pcie_physical_function: > + Property specifies which PCIe physical function the subsystem node resides. > +:pcie_bar_mapping: > + Property specifies which PCIe BAR the subsystem node resides. '<0x2>' is BAR > + index and it is 0 if this property is not defined. > +:compatible: > + Property is a list of strings. The first string in the list specifies the exact > + subsystem node. The following strings represent other devices that the device > + is compatible with. > +:firmware: > + Subnode defines the firmware required by this subsystem node. > + > +Alveo U50 Platform Example > +^^^^^^^^^^^^^^^^^^^^^^^^^^ > +:: > + > + /dts-v1/; > + > + /{ > + logic_uuid = "f465b0a3ae8c64f619bc150384ace69b"; > + > + schema_version { > + major = <0x01>; > + minor = <0x00>; > + }; > + > + interfaces { > + > + @0 { > + interface_uuid = "862c7020a250293e32036f19956669e5"; > + }; > + }; > + > + addressable_endpoints { > + > + ep_blp_rom_00 { > + reg = <0x00 0x1f04000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; Shouldn't that be xlnx,... ? > + }; > + > + ep_card_flash_program_00 { > + reg = <0x00 0x1f06000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_quad_spi-1.0\0axi_quad_spi"; > + interrupts = <0x03 0x03>; > + }; > + > + ep_cmc_firmware_mem_00 { > + reg = <0x00 0x1e20000 0x00 0x20000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + > + firmware { > + firmware_product_name = "cmc"; > + firmware_branch_name = "u50"; > + firmware_version_major = <0x01>; > + firmware_version_minor = <0x00>; > + }; > + }; > + > + ep_cmc_intc_00 { > + reg = <0x00 0x1e03000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_intc-1.0\0axi_intc"; > + interrupts = <0x04 0x04>; > + }; > + > + ep_cmc_mutex_00 { > + reg = <0x00 0x1e02000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_cmc_regmap_00 { > + reg = <0x00 0x1e08000 0x00 0x2000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + > + firmware { > + firmware_product_name = "sc-fw"; > + firmware_branch_name = "u50"; > + firmware_version_major = <0x05>; > + }; > + }; > + > + ep_cmc_reset_00 { > + reg = <0x00 0x1e01000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_ddr_mem_calib_00 { > + reg = <0x00 0x63000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_debug_bscan_mgmt_00 { > + reg = <0x00 0x1e90000 0x00 0x10000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-debug_bridge-1.0\0debug_bridge"; > + }; > + > + ep_ert_base_address_00 { > + reg = <0x00 0x21000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_ert_command_queue_mgmt_00 { > + reg = <0x00 0x40000 0x00 0x10000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-ert_command_queue-1.0\0ert_command_queue"; > + }; > + > + ep_ert_command_queue_user_00 { > + reg = <0x00 0x40000 0x00 0x10000>; > + pcie_physical_function = <0x01>; > + compatible = "xilinx.com,reg_abs-ert_command_queue-1.0\0ert_command_queue"; > + }; > + > + ep_ert_firmware_mem_00 { > + reg = <0x00 0x30000 0x00 0x8000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + > + firmware { > + firmware_product_name = "ert"; > + firmware_branch_name = "v20"; > + firmware_version_major = <0x01>; > + }; > + }; > + > + ep_ert_intc_00 { > + reg = <0x00 0x23000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_intc-1.0\0axi_intc"; > + interrupts = <0x05 0x05>; > + }; > + > + ep_ert_reset_00 { > + reg = <0x00 0x22000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_ert_sched_00 { > + reg = <0x00 0x50000 0x00 0x1000>; > + pcie_physical_function = <0x01>; > + compatible = "xilinx.com,reg_abs-ert_sched-1.0\0ert_sched"; > + interrupts = <0x09 0x0c>; > + }; > + > + ep_fpga_configuration_00 { > + reg = <0x00 0x1e88000 0x00 0x8000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_hwicap-1.0\0axi_hwicap"; > + interrupts = <0x02 0x02>; > + }; > + > + ep_icap_reset_00 { > + reg = <0x00 0x1f07000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_msix_00 { > + reg = <0x00 0x00 0x00 0x20000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-msix-1.0\0msix"; > + pcie_bar_mapping = <0x02>; > + }; > + > + ep_pcie_link_mon_00 { > + reg = <0x00 0x1f05000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_pr_isolate_plp_00 { > + reg = <0x00 0x1f01000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_pr_isolate_ulp_00 { > + reg = <0x00 0x1000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; > + }; > + > + ep_uuid_rom_00 { > + reg = <0x00 0x64000 0x00 0x1000>; > + pcie_physical_function = <0x00>; > + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; > + }; > + > + ep_xdma_00 { > + reg = <0x00 0x00 0x00 0x10000>; > + pcie_physical_function = <0x01>; > + compatible = "xilinx.com,reg_abs-xdma-1.0\0xdma"; > + pcie_bar_mapping = <0x02>; > + }; > + }; > + > + } > + > + > + > +Deployment Models > +================= > + > +Baremetal > +--------- > + > +In bare-metal deployments, both MPF and UPF are visible and accessible. xrt-mgnt > +driver binds to MPF. xrt-mgnt driver operations are privileged and available to > +system administrator. The full stack is illustrated below:: > + > + HOST > + > + [XRT-MGNT] [XRT-USER] > + | | > + | | > + +-----+ +-----+ > + | MPF | | UPF | > + | | | | > + | PF0 | | PF1 | > + +--+--+ +--+--+ > + ......... ^................. ^.......... > + | | > + | PCIe DEVICE | > + | | > + +--+------------------+--+ > + | SHELL | > + | | > + +------------------------+ > + | USER | > + | | > + | | > + | | > + | | > + +------------------------+ > + > + > + > +Virtualized > +----------- > + > +In virtualized deployments, privileged MPF is assigned to host but unprivileged > +UPF is assigned to guest VM via PCIe pass-through. xrt-mgnt driver in host binds > +to MPF. xrt-mgnt driver operations are privileged and only accessible to the MPF. > +The full stack is illustrated below:: > + > + > + .............. > + HOST . VM . > + . . > + [XRT-MGNT] . [XRT-USER] . > + | . | . > + | . | . > + +-----+ . +-----+ . > + | MPF | . | UPF | . > + | | . | | . > + | PF0 | . | PF1 | . > + +--+--+ . +--+--+ . > + ......... ^................. ^.......... > + | | > + | PCIe DEVICE | > + | | > + +--+------------------+--+ > + | SHELL | > + | | > + +------------------------+ > + | USER | > + | | > + | | > + | | > + | | > + +------------------------+ > + > + > + > + > + > +Platform Security Considerations > +================================ > + > +`Security of Alveo Platform <https://xilinx.github.io/XRT/master/html/security.html>`_ > +discusses the deployment options and security implications in great detail. > -- > 2.27.0 > Thanks, Moritz
diff --git a/Documentation/fpga/index.rst b/Documentation/fpga/index.rst index f80f95667ca2..30134357b70d 100644 --- a/Documentation/fpga/index.rst +++ b/Documentation/fpga/index.rst @@ -8,6 +8,7 @@ fpga :maxdepth: 1 dfl + xrt .. only:: subproject and html diff --git a/Documentation/fpga/xrt.rst b/Documentation/fpga/xrt.rst new file mode 100644 index 000000000000..c9faad5f18c4 --- /dev/null +++ b/Documentation/fpga/xrt.rst @@ -0,0 +1,844 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================== +XRTV2 Linux Kernel Driver Overview +================================== + +Authors: + +* Sonal Santan <sonal.santan@xilinx.com> +* Max Zhen <max.zhen@xilinx.com> +* Lizhi Hou <lizhi.hou@xilinx.com> + +XRTV2 drivers are second generation `XRT <https://github.com/Xilinx/XRT>`_ +drivers which support `Alveo <https://www.xilinx.com/products/boards-and-kits/alveo.html>`_ +PCIe platforms from Xilinx. + +XRTV2 drivers support *subsystem* style data driven platforms where driver's +configuration and behavior is determined by meta data provided by the platform +(in *device tree* format). Primary management physical function (MPF) driver +is called **xrt-mgnt**. Primary user physical function (UPF) driver is called +**xrt-user** and is under development. xrt driver framework and HW subsystem +drivers are packaged into a library module called **xrt-lib**, which is shared +by **xrt-mgnt** and **xrt-user** (under development). The xrt driver framework +implements a ``bus_type`` called **xrt_bus_type** which is used to discover HW +subsystems and facilitate inter HW subsystem interaction. + +Driver Modules +============== + +xrt-lib.ko +---------- + +Repository of all subsystem drivers and pure software modules that can potentially +be shared between xrt-mgnt and xrt-user. All these drivers are structured as +**xrt_driver** and are instantiated by xrt-mgnt (or xrt-user under development) +based on meta data associated with the hardware. The metadata is in the form of a +device tree as mentioned before. Each xrt driver statically defines a subsystem +node array by using node name or a string in its ``.endpoints`` property. And this +array is eventually translated to IOMEM resources in the instantiated xrt device. + +The xrt-lib infrastructure provides hooks to xrt drivers for device node +management, user file operations and ioctl callbacks. The core infrastructure also +provides bus functionality for xrt driver registration, discovery and inter xrt +driver leaf calls. + +.. note:: + See code in ``include/xleaf.h`` and ``include/xdevice.h`` + + +xrt-mgnt.ko +------------ + +The xrt-mgnt driver is a PCIe device driver driving MPF found on Xilinx's Alveo +PCIe device. It consists of one *root* driver, one or more *group* drivers +and one or more *xleaf* drivers. The root and MPF specific xleaf drivers are +in xrt-mgnt.ko. The group driver and other xleaf drivers are in xrt-lib.ko. + +The instantiation of specific group driver or xleaf driver is completely data +driven based on meta data (mostly in device tree format) found through VSEC +capability and inside firmware files, such as platform xsabin or user xclbin file. +The root driver manages the life cycle of multiple group drivers, which, in turn, +manages multiple xleaf drivers. This allows a single set of drivers to support +all kinds of subsystems exposed by different shells. The difference among all +these subsystems will be handled in xleaf drivers with root and group drivers +being part of the infrastructure and provide common services for all leaves +found on all platforms. + +The driver object model looks like the following:: + + +-----------+ + | xroot | + +-----+-----+ + | + +-----------+-----------+ + | | + v v + +-----------+ +-----------+ + | group | ... | group | + +-----+-----+ +------+----+ + | | + | | + +-----+----+ +-----+----+ + | | | | + v v v v + +-------+ +-------+ +-------+ +-------+ + | xleaf |..| xleaf | | xleaf |..| xleaf | + +-------+ +-------+ +-------+ +-------+ + +As an example for Xilinx Alveo U50 before user xclbin download, the tree +looks like the following:: + + +-----------+ + | xrt-mgnt | + +-----+-----+ + | + +-------------------------+--------------------+ + | | | + v v v + +--------+ +--------+ +--------+ + | group0 | | group1 | | group2 | + +----+---+ +----+---+ +---+----+ + | | | + | | | + +-----+-----+ +----+-----+---+ +-----+-----+----+--------+ + | | | | | | | | | + v v | v v | v v | + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | + | xmgnt_main | | VSEC | | | GPIO | | QSPI | | | CMC | | AXI-GATE0 | | + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | + | +---------+ | +------+ +-----------+ | + +>| MAILBOX | +->| ICAP | | AXI-GATE1 |<+ + +---------+ | +------+ +-----------+ + | +-------+ + +->| CALIB | + +-------+ + +After an xclbin is downloaded, group3 will be added and the tree looks like the +following:: + + +-----------+ + | xrt-mgnt | + +-----+-----+ + | + +-------------------------+--------------------+-----------------+ + | | | | + v v v | + +--------+ +--------+ +--------+ | + | group0 | | group1 | | group2 | | + +----+---+ +----+---+ +---+----+ | + | | | | + | | | | + +-----+-----+ +-----+-----+---+ +-----+-----+----+--------+ | + | | | | | | | | | | + v v | v v | v v | | + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | | + | xmgnt_main | | VSEC | | | GPIO | | QSPI | | | CMC | | AXI-GATE0 | | | + +------------+ +------+ | +------+ +------+ | +------+ +-----------+ | | + | +---------+ | +------+ +-----------+ | | + +>| MAILBOX | +->| ICAP | | AXI-GATE1 |<+ | + +---------+ | +------+ +-----------+ | + | +-------+ | + +->| CALIB | | + +-------+ | + +---+----+ | + | group3 |<--------------------------------------------+ + +--------+ + | + | + +-------+--------+---+--+--------+------+-------+ + | | | | | | | + v | v | v | v + +--------+ | +--------+ | +--------+ | +-----+ + | CLOCK0 | | | CLOCK1 | | | CLOCK2 | | | UCS | + +--------+ v +--------+ v +--------+ v +-----+ + +-------------+ +-------------+ +-------------+ + | CLOCK-FREQ0 | | CLOCK-FREQ1 | | CLOCK-FREQ2 | + +-------------+ +-------------+ +-------------+ + + +root +^^^^ + +The root driver is a PCIe device driver attached to MPF. It's part of the +infrastructure of the MPF driver and resides in xrt-mgnt.ko. This driver + +* manages one or more group drivers +* provides access to functionalities that requires pci_dev, such as PCIE config + space access, to other xleaf drivers through root calls +* facilities event callbacks for other xleaf drivers +* facilities inter-leaf driver calls for other xleaf drivers + +When root driver starts, it will explicitly create an initial group instance, +which contains xleaf drivers that will trigger the creation of other group +instances. The root driver will wait for all group and leaves to be created +before it returns from it's probe routine and claim success of the +initialization of the entire xrt-mgnt driver. If any leaf fails to initialize +the xrt-mgnt driver will still come online but with limited functionality. + +.. note:: + See code in ``lib/xroot.c`` and ``mgnt/root.c`` + + +group +^^^^^ + +The group driver represents a pseudo device whose life cycle is managed by +root and does not have real IO mem or IRQ resources. It's part of the +infrastructure of the MPF driver and resides in xrt-lib.ko. This driver + +* manages one or more xleaf drivers +* provides access to root from leaves, so that root calls, event notifications + and inter-leaf calls can happen + +In xrt-mgnt, an initial group driver instance will be created by the root. This +instance contains leaves that will trigger group instances to be created to +manage groups of leaves found on different partitions on hardware, such as +VSEC, Shell, and User. + +Every *fpga_region* has a group object associated with it. The group is +created when xclbin image is loaded on the fpga_region. The existing group +is destroyed when a new xclbin image is loaded. The fpga_region persists +across xclbin downloads. + +.. note:: + See code in ``lib/group.c`` + + +xleaf +^^^^^ + +The xleaf driver is a xrt device driver whose life cycle is managed by +a group driver and may or may not have real IO mem or IRQ resources. They +are the real meat of xrt-mgnt and manage HW subsystems they are attached to. + +A xleaf driver may not have real hardware resources when it merely acts as a +driver that manages certain in-memory states for xrt-mgnt. These in-memory +states could be shared by multiple other leaves. + +Leaf drivers assigned to specific hardware resources drive specific subsystem in +the device. To manipulate the subsystem or carry out a task, a xleaf driver may +ask help from the root via root calls and/or from other leaves via inter-leaf +calls. + +A xleaf can also broadcast events through infrastructure code for other leaves +to process. It can also receive event notification from infrastructure about +certain events, such as post-creation or pre-exit of a particular xleaf. + +.. note:: + See code in ``lib/xleaf/*.c`` + + +FPGA Manager Interaction +======================== + +fpga_manager +------------ + +An instance of fpga_manager is created by xmgnt_main and is used for xclbin +image download. fpga_manager requires the full xclbin image before it can +start programming the FPGA configuration engine via Internal Configuration +Access Port (ICAP) xrt driver. + +fpga_region +----------- + +For every interface exposed by the currently loaded xclbin/xsabin in the +*parent* fpga_region a new instance of fpga_region is created like a *child* +fpga_region. The device tree of the *parent* fpga_region defines the +resources for a new instance of fpga_bridge which isolates the parent from +child fpga_region. This new instance of fpga_bridge will be used when a +xclbin image is loaded on the child fpga_region. After the xclbin image is +downloaded to the fpga_region, an instance of group is created for the +fpga_region using the device tree obtained as part of the xclbin. If this +device tree defines any child interfaces then it can trigger the creation of +fpga_bridge and fpga_region for the next region in the chain. + +fpga_bridge +----------- + +Like the fpga_region, matching fpga_bridge is also created by walking the +device tree of the parent group. + +Driver Interfaces +================= + +xrt-mgnt Driver Ioctls +---------------------- + +Ioctls exposed by xrt-mgnt driver to user space are enumerated in the following +table: + +== ===================== ============================ ========================== +# Functionality ioctl request code data format +== ===================== ============================ ========================== +1 FPGA image download XMGNT_IOCICAPDOWNLOAD_AXLF xmgnt_ioc_bitstream_axlf +== ===================== ============================ ========================== + +A user xclbin can be downloaded by using the xbmgmt tool from the XRT open source +suite. See example usage below:: + + xbmgmt partition --program --path /lib/firmware/xilinx/862c7020a250293e32036f19956669e5/test/verify.xclbin --force + +xrt-mgnt Driver Sysfs +---------------------- + +xrt-mgnt driver exposes a rich set of sysfs interfaces. Subsystem xrt +drivers export sysfs node for every platform instance. + +Every partition also exports its UUIDs. See below for examples:: + + /sys/bus/pci/devices/0000:06:00.0/xmgnt_main.0/interface_uuids + /sys/bus/pci/devices/0000:06:00.0/xmgnt_main.0/logic_uuids + + +hwmon +----- + +xmgnt driver exposes standard hwmon interface to report voltage, current, +temperature, power, etc. These can easily be viewed using *sensors* command +line utility. + +Alveo Platform Overview +======================= + +Alveo platforms are architected as two physical FPGA partitions: *Shell* and +*User*. The Shell provides basic infrastructure for the Alveo platform like +PCIe connectivity, board management, Dynamic Function Exchange (DFX), sensors, +clocking, reset, and security. User partition contains user compiled FPGA +binary which is loaded by a process called DFX also known as partial +reconfiguration. + +For DFX to work properly physical partitions require strict HW compatibility +with each other. Every physical partition has two interface UUIDs: *parent* UUID +and *child* UUID. For simple single stage platforms, Shell → User forms parent +child relationship. + +.. note:: + Partition compatibility matching is key design component of Alveo platforms + and XRT. Partitions have child and parent relationship. A loaded partition + exposes child partition UUID to advertise its compatibility requirement.When + loading a child partition the xrt-mgnt management driver matches parent UUID of + the child partition against child UUID exported by the parent. Parent and + child partition UUIDs are stored in the *xclbin* (for user) or *xsabin* (for + shell). Except for root UUID exported by VSEC, hardware itself does not know + about UUIDs. UUIDs are stored in xsabin and xclbin. The image format has a + special node called Partition UUIDs which define the compatibility UUIDs. See + :ref:`partition_uuids`. + + +The physical partitions and their loading is illustrated below:: + + SHELL USER + +-----------+ +-------------------+ + | | | | + | VSEC UUID | CHILD PARENT | LOGIC UUID | + | o------->|<--------o | + | | UUID UUID | | + +-----+-----+ +--------+----------+ + | | + . . + | | + +---+---+ +------+--------+ + | POR | | USER COMPILED | + | FLASH | | XCLBIN | + +-------+ +---------------+ + + +Loading Sequence +---------------- + +The Shell partition is loaded from flash at system boot time. It establishes the +PCIe link and exposes two physical functions to the BIOS. After the OS boots, xrt-mgnt +driver attaches to the PCIe physical function 0 exposed by the Shell and then looks +for VSEC in PCIe extended configuration space. Using VSEC it determines the logic +UUID of Shell and uses the UUID to load matching *xsabin* file from Linux firmware +directory. The xsabin file contains metadata to discover peripherals that are part +of Shell and firmware(s) for any embedded soft processors in Shell. The xsabin file +also contains Partition UUIDs as described here :ref:`partition_uuids`. + +The Shell exports a child interface UUID which is used for the compatibility check +when loading user compiled xclbin over the User partition as part of DFX. When a user +requests loading of a specific xclbin the xrt-mgnt management driver reads the parent +interface UUID specified in the xclbin and matches it with child interface UUID +exported by Shell to determine if xclbin is compatible with the Shell. If match +fails loading of xclbin is denied. + +xclbin loading is requested using ICAP_DOWNLOAD_AXLF ioctl command. When loading +xclbin, xrt-mgnt driver performs the following *logical* operations: + +1. Copy xclbin from user to kernel memory +2. Sanity check the xclbin contents +3. Isolate the User partition +4. Download the bitstream using the FPGA config engine (ICAP) +5. De-isolate the User partition +6. Program the clocks (ClockWiz) driving the User partition +7. Wait for memory controller (MIG) calibration +8. Return the loading status back to the caller + +`Platform Loading Overview <https://xilinx.github.io/XRT/master/html/platforms_partitions.html>`_ +provides more detailed information on platform loading. + + +xsabin +------ + +Each Alveo platform comes packaged with its own xsabin. The xsabin is a trusted +component of the platform. For format details refer to :ref:`xsabin_xclbin_container_format` +below. xsabin contains basic information like UUIDs, platform name and metadata in the +form of device tree. See :ref:`device_tree_usage` below for details and example. + +xclbin +------ + +xclbin is compiled by end user using +`Vitis <https://www.xilinx.com/products/design-tools/vitis/vitis-platform.html>`_ +tool set from Xilinx. The xclbin contains sections describing user compiled +acceleration engines/kernels, memory subsystems, clocking information etc. It also +contains FPGA bitstream for the user partition, UUIDs, platform name, etc. + + +.. _xsabin_xclbin_container_format: + +xsabin/xclbin Container Format +------------------------------ + +xclbin/xsabin is ELF-like binary container format. It is structured as series of +sections. There is a file header followed by several section headers which is +followed by sections. A section header points to an actual section. There is an +optional signature at the end. The format is defined by header file ``xclbin.h``. +The following figure illustrates a typical xclbin:: + + + +---------------------+ + | | + | HEADER | + +---------------------+ + | SECTION HEADER | + | | + +---------------------+ + | ... | + | | + +---------------------+ + | SECTION HEADER | + | | + +---------------------+ + | SECTION | + | | + +---------------------+ + | ... | + | | + +---------------------+ + | SECTION | + | | + +---------------------+ + | SIGNATURE | + | (OPTIONAL) | + +---------------------+ + + +xclbin/xsabin files can be packaged, un-packaged and inspected using XRT utility +called **xclbinutil**. xclbinutil is part of XRT open source software stack. The +source code for xclbinutil can be found at +https://github.com/Xilinx/XRT/tree/master/src/runtime_src/tools/xclbinutil + +For example to enumerate the contents of a xclbin/xsabin use the *--info* switch +as shown below:: + + + xclbinutil --info --input /opt/xilinx/firmware/u50/gen3x16-xdma/blp/test/bandwidth.xclbin + xclbinutil --info --input /lib/firmware/xilinx/862c7020a250293e32036f19956669e5/partition.xsabin + + +.. _device_tree_usage: + +Device Tree Usage +----------------- + +As mentioned previously xsabin file stores metadata which advertise HW subsystems present +in a partition. The metadata is stored in device tree format with a well defined schema. +XRT management driver uses this information to bind *xrt drivers* to the subsystem +instantiations. The xrt drivers are found in **xrt-lib.ko** kernel module defined +earlier. + +Logic UUID +^^^^^^^^^^ +A partition is identified uniquely through ``logic_uuid`` property:: + + /dts-v1/; + / { + logic_uuid = "0123456789abcdef0123456789abcdef"; + ... + } + +Schema Version +^^^^^^^^^^^^^^ +Schema version is defined through ``schema_version`` node. And it contains ``major`` +and ``minor`` properties as below:: + + /dts-v1/; + / { + schema_version { + major = <0x01>; + minor = <0x00>; + }; + ... + } + +.. _partition_uuids: + +Partition UUIDs +^^^^^^^^^^^^^^^ +As mentioned earlier, each partition may have parent and child UUIDs. These UUIDs are +defined by ``interfaces`` node and ``interface_uuid`` property:: + + /dts-v1/; + / { + interfaces { + @0 { + interface_uuid = "0123456789abcdef0123456789abcdef"; + }; + @1 { + interface_uuid = "fedcba9876543210fedcba9876543210"; + }; + ... + }; + ... + } + + +Subsystem Instantiations +^^^^^^^^^^^^^^^^^^^^^^^^ +Subsystem instantiations are captured as children of ``addressable_endpoints`` +node:: + + /dts-v1/; + / { + addressable_endpoints { + abc { + ... + }; + def { + ... + }; + ... + } + } + +Subnode 'abc' and 'def' are the name of subsystem nodes + +Subsystem Node +^^^^^^^^^^^^^^ +Each subsystem node and its properties define a hardware instance:: + + + addressable_endpoints { + abc { + reg = <0xa 0xb> + pcie_physical_function = <0x0>; + pcie_bar_mapping = <0x2>; + compatible = "abc def"; + firmware { + firmware_product_name = "abc" + firmware_branch_name = "def" + firmware_version_major = <1> + firmware_version_minor = <2> + }; + } + ... + } + +:reg: + Property defines address range. '<0xa 0xb>' is BAR offset and length pair, both + are 64-bit integer. +:pcie_physical_function: + Property specifies which PCIe physical function the subsystem node resides. +:pcie_bar_mapping: + Property specifies which PCIe BAR the subsystem node resides. '<0x2>' is BAR + index and it is 0 if this property is not defined. +:compatible: + Property is a list of strings. The first string in the list specifies the exact + subsystem node. The following strings represent other devices that the device + is compatible with. +:firmware: + Subnode defines the firmware required by this subsystem node. + +Alveo U50 Platform Example +^^^^^^^^^^^^^^^^^^^^^^^^^^ +:: + + /dts-v1/; + + /{ + logic_uuid = "f465b0a3ae8c64f619bc150384ace69b"; + + schema_version { + major = <0x01>; + minor = <0x00>; + }; + + interfaces { + + @0 { + interface_uuid = "862c7020a250293e32036f19956669e5"; + }; + }; + + addressable_endpoints { + + ep_blp_rom_00 { + reg = <0x00 0x1f04000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; + }; + + ep_card_flash_program_00 { + reg = <0x00 0x1f06000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_quad_spi-1.0\0axi_quad_spi"; + interrupts = <0x03 0x03>; + }; + + ep_cmc_firmware_mem_00 { + reg = <0x00 0x1e20000 0x00 0x20000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; + + firmware { + firmware_product_name = "cmc"; + firmware_branch_name = "u50"; + firmware_version_major = <0x01>; + firmware_version_minor = <0x00>; + }; + }; + + ep_cmc_intc_00 { + reg = <0x00 0x1e03000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_intc-1.0\0axi_intc"; + interrupts = <0x04 0x04>; + }; + + ep_cmc_mutex_00 { + reg = <0x00 0x1e02000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_cmc_regmap_00 { + reg = <0x00 0x1e08000 0x00 0x2000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; + + firmware { + firmware_product_name = "sc-fw"; + firmware_branch_name = "u50"; + firmware_version_major = <0x05>; + }; + }; + + ep_cmc_reset_00 { + reg = <0x00 0x1e01000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_ddr_mem_calib_00 { + reg = <0x00 0x63000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_debug_bscan_mgmt_00 { + reg = <0x00 0x1e90000 0x00 0x10000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-debug_bridge-1.0\0debug_bridge"; + }; + + ep_ert_base_address_00 { + reg = <0x00 0x21000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_ert_command_queue_mgmt_00 { + reg = <0x00 0x40000 0x00 0x10000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-ert_command_queue-1.0\0ert_command_queue"; + }; + + ep_ert_command_queue_user_00 { + reg = <0x00 0x40000 0x00 0x10000>; + pcie_physical_function = <0x01>; + compatible = "xilinx.com,reg_abs-ert_command_queue-1.0\0ert_command_queue"; + }; + + ep_ert_firmware_mem_00 { + reg = <0x00 0x30000 0x00 0x8000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; + + firmware { + firmware_product_name = "ert"; + firmware_branch_name = "v20"; + firmware_version_major = <0x01>; + }; + }; + + ep_ert_intc_00 { + reg = <0x00 0x23000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_intc-1.0\0axi_intc"; + interrupts = <0x05 0x05>; + }; + + ep_ert_reset_00 { + reg = <0x00 0x22000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_ert_sched_00 { + reg = <0x00 0x50000 0x00 0x1000>; + pcie_physical_function = <0x01>; + compatible = "xilinx.com,reg_abs-ert_sched-1.0\0ert_sched"; + interrupts = <0x09 0x0c>; + }; + + ep_fpga_configuration_00 { + reg = <0x00 0x1e88000 0x00 0x8000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_hwicap-1.0\0axi_hwicap"; + interrupts = <0x02 0x02>; + }; + + ep_icap_reset_00 { + reg = <0x00 0x1f07000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_msix_00 { + reg = <0x00 0x00 0x00 0x20000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-msix-1.0\0msix"; + pcie_bar_mapping = <0x02>; + }; + + ep_pcie_link_mon_00 { + reg = <0x00 0x1f05000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_pr_isolate_plp_00 { + reg = <0x00 0x1f01000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_pr_isolate_ulp_00 { + reg = <0x00 0x1000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_gpio-1.0\0axi_gpio"; + }; + + ep_uuid_rom_00 { + reg = <0x00 0x64000 0x00 0x1000>; + pcie_physical_function = <0x00>; + compatible = "xilinx.com,reg_abs-axi_bram_ctrl-1.0\0axi_bram_ctrl"; + }; + + ep_xdma_00 { + reg = <0x00 0x00 0x00 0x10000>; + pcie_physical_function = <0x01>; + compatible = "xilinx.com,reg_abs-xdma-1.0\0xdma"; + pcie_bar_mapping = <0x02>; + }; + }; + + } + + + +Deployment Models +================= + +Baremetal +--------- + +In bare-metal deployments, both MPF and UPF are visible and accessible. xrt-mgnt +driver binds to MPF. xrt-mgnt driver operations are privileged and available to +system administrator. The full stack is illustrated below:: + + HOST + + [XRT-MGNT] [XRT-USER] + | | + | | + +-----+ +-----+ + | MPF | | UPF | + | | | | + | PF0 | | PF1 | + +--+--+ +--+--+ + ......... ^................. ^.......... + | | + | PCIe DEVICE | + | | + +--+------------------+--+ + | SHELL | + | | + +------------------------+ + | USER | + | | + | | + | | + | | + +------------------------+ + + + +Virtualized +----------- + +In virtualized deployments, privileged MPF is assigned to host but unprivileged +UPF is assigned to guest VM via PCIe pass-through. xrt-mgnt driver in host binds +to MPF. xrt-mgnt driver operations are privileged and only accessible to the MPF. +The full stack is illustrated below:: + + + .............. + HOST . VM . + . . + [XRT-MGNT] . [XRT-USER] . + | . | . + | . | . + +-----+ . +-----+ . + | MPF | . | UPF | . + | | . | | . + | PF0 | . | PF1 | . + +--+--+ . +--+--+ . + ......... ^................. ^.......... + | | + | PCIe DEVICE | + | | + +--+------------------+--+ + | SHELL | + | | + +------------------------+ + | USER | + | | + | | + | | + | | + +------------------------+ + + + + + +Platform Security Considerations +================================ + +`Security of Alveo Platform <https://xilinx.github.io/XRT/master/html/security.html>`_ +discusses the deployment options and security implications in great detail.