RFC : [PATCH V7 XRT Alveo 00/20] XRT Alveo driver overview

From: Tom Rix
Date: Thu Jun 03 2021 - 10:23:22 EST



On 6/2/21 3:34 PM, Lizhi Hou wrote:
Hi Moritz and Tom,

Thanks a lot for reviewing the XRT patches. This v7 patches contains our latest fixes for all review comments. And it seems auto build robot is happy with it as well. Do you have more comment against v7? What will be the next step for XRT patches if it looks ok to you?

Please do not add any features to the patchset.

When you add a feature, that tends to reset the review process.


For little stuff.

I need to look at the documentation again, iirc that was the only issue in v6.


For big stuff.

At the beginning some possible refactor questions were raised, I don't know if they have been resolved.

ex/

some of the leaf drivers like clock should be moved the clock subsystem

the xrt/ dir vs existing flat, we don't want both.

is your xrt bus consistent with dfl bus, can it support adding devices outside of fpga/xrt

how clean are the public headers


Since flipflopping on refactoring is a painful, let's try to get a consensus before moving forward.

This may mean the patchset is committed by parts as it and the existing code changes.


Lets start with the directory structure.

Since there are a lot of files in xrt, the xrt/ makes sense.

For other fpga's with a lot of files, say > 3, we need to change ex/

dfl-foo.c to dfl/foo.c

to be consistent.


The Kconfig and Makefiles for xrt/ and dfl/ would only be in that top subdir.

Which i think is a change for xrt/


I'll whip up something for dfl/ to move things along.

Tom



Thanks,

Lizhi


On 05/27/2021 05:49 PM, Lizhi Hou wrote:
Hello,

This is V7 of patch series which adds management physical function driver
for Xilinx Alveo PCIe accelerator cards.
     https://www.xilinx.com/products/boards-and-kits/alveo.html

This driver is part of Xilinx Runtime (XRT) open source stack.

XILINX ALVEO PLATFORM ARCHITECTURE

Alveo PCIe FPGA based platforms have a static *shell* partition and a
partial re-configurable *user* partition. The shell partition is
automatically loaded from flash when host is booted and PCIe is enumerated
by BIOS. Shell cannot be changed till the next cold reboot. The shell
exposes two PCIe physical functions:

1. management physical function
2. user physical function

The patch series includes Documentation/xrt.rst which describes Alveo
platform, XRT driver architecture and deployment model in more detail.

Users compile their high level design in C/C++/OpenCL or RTL into FPGA
image using Vitis tools.
https://www.xilinx.com/products/design-tools/vitis/vitis-platform.html

The compiled image is packaged as xclbin which contains partial bitstream
for the user partition and necessary metadata. Users can dynamically swap
the image running on the user partition in order to switch between
different workloads by loading different xclbins.

XRT DRIVERS FOR XILINX ALVEO

XRT Linux kernel driver *xrt-mgmt* binds to management physical function of
Alveo platform. The modular driver framework is organized into several
platform drivers which primarily handle the following functionality:

1.  Loading firmware container also called xsabin at driver attach time
2.  Loading of user compiled xclbin with FPGA Manager integration
3.  Clock scaling of image running on user partition
4.  In-band sensors: temp, voltage, power, etc.
5.  Device reset and rescan

The platform drivers are packaged into *xrt-lib* helper module with well
defined interfaces. The module provides a pseudo-bus implementation for the
platform drivers. More details on the driver model can be found in
Documentation/xrt.rst.

User physical function driver is not included in this patch series.

LIBFDT REQUIREMENT

XRT driver infrastructure uses Device Tree as a metadata format to discover
HW subsystems in the Alveo PCIe device. The Device Tree schema used by XRT
is documented in Documentation/xrt.rst.

TESTING AND VALIDATION

xrt-mgmt driver can be tested with full XRT open source stack which
includes user space libraries, board utilities and (out of tree) first
generation user physical function driver xocl. XRT open source runtime
stack is available at https://github.com/Xilinx/XRT

Complete documentation for XRT open source stack including sections on
Alveo/XRT security and platform architecture can be found here:

https://xilinx.github.io/XRT/master/html/index.html
https://xilinx.github.io/XRT/master/html/security.html
https://xilinx.github.io/XRT/master/html/platforms_partitions.html

Changes since v6:
- Resolved grammatical errors and cleaned up taxonomy in xrt.rst
   documentation.
- Fixed clang warnings.
- Updated code base to include v6 code review comments.

Changes since v5:
- Revert all changes 'mgnt/MGNT' back to 'mgmt/MGMT'
- Updated code base to include v5 code review comments.
    xrt.rst: address grammar and taxonomy
    subdev_id.h: defines XRT_SUBDEV_INVALID = 0
    xclbin.c: change shift operation to be_to_cpu
- Resolved kernel test robot errors.

Changes since v4:
- Added xrt_bus_type and xrt_device. All sub devices were changed from
   platform_bus_type/platform_device to xrt_bus_type/xrt_device.
- Renamed xrt-mgmt driver to xrt-mgnt driver.
- Replaced 'MGMT' with 'MGNT' and 'mgmt' with 'mgnt' in code and file names
- Moved pci function calls from infrastructure to xrt-mgnt driver.
- Renamed files: mgmt/main.c -> mgnt/xmgnt-main.c
                  mgmt/main-region.c -> mgnt/xmgnt-main-region.c
                  include/xmgmt-main.h -> include/xmgnt-main.h
                  mgmt/fmgr-drv.c -> mgnt/xrt-mgr.c
                  mgmt/fmgr.h -> mgnt/xrt-mgr.h
- Updated code base to include v4 code review comments.

Changes since v3:
- Leaf drivers use regmap-mmio to access hardware registers.
- Renamed driver module: xmgmt.ko -> xrt-mgmt.ko
- Renamed files: calib.[c|h] -> ddr_calibration.[c|h],
                  lib/main.[c|h] -> lib/lib-drv.[c|h],
                  mgmt/main-impl.h - > mgmt/xmgnt.h
- Updated code base to include v3 code review comments.

Changes since v2:
- Streamlined the driver framework into *xleaf*, *group* and *xroot*
- Updated documentation to show the driver model with examples
- Addressed kernel test robot errors
- Added a selftest for basic driver framework
- Documented device tree schema
- Removed need to export libfdt symbols

Changes since v1:
- Updated the driver to use fpga_region and fpga_bridge for FPGA
   programming
- Dropped platform drivers not related to PR programming to focus on XRT
   core framework
- Updated Documentation/fpga/xrt.rst with information on XRT core framework
- Addressed checkpatch issues
- Dropped xrt- prefix from some header files

For reference V6 version of patch series can be found here:

https://lore.kernel.org/lkml/20210512015339.5649-1-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-2-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-3-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-4-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-5-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-6-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-7-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-8-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-9-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-10-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-11-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-12-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-13-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-14-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-15-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-16-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-17-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-18-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-19-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-20-lizhi.hou@xxxxxxxxxx/
https://lore.kernel.org/lkml/20210512015339.5649-21-lizhi.hou@xxxxxxxxxx/

Lizhi Hou (20):
   Documentation: fpga: Add a document describing XRT Alveo drivers
   fpga: xrt: driver metadata helper functions
   fpga: xrt: xclbin file helper functions
   fpga: xrt: xrt-lib driver manager
   fpga: xrt: group driver
   fpga: xrt: char dev node helper functions
   fpga: xrt: root driver infrastructure
   fpga: xrt: driver infrastructure
   fpga: xrt: management physical function driver (root)
   fpga: xrt: main driver for management function device
   fpga: xrt: fpga-mgr and region implementation for xclbin download
   fpga: xrt: VSEC driver
   fpga: xrt: User Clock Subsystem driver
   fpga: xrt: ICAP driver
   fpga: xrt: devctl xrt driver
   fpga: xrt: clock driver
   fpga: xrt: clock frequency counter driver
   fpga: xrt: DDR calibration driver
   fpga: xrt: partition isolation driver
   fpga: xrt: Kconfig and Makefile updates for XRT drivers

  Documentation/fpga/index.rst                  |   1 +
  Documentation/fpga/xrt.rst                    | 870 ++++++++++++++++++
  MAINTAINERS                                   |  11 +
  drivers/Makefile                              |   1 +
  drivers/fpga/Kconfig                          |   2 +
  drivers/fpga/Makefile                         |   5 +
  drivers/fpga/xrt/Kconfig                      |   8 +
  drivers/fpga/xrt/include/events.h             |  45 +
  drivers/fpga/xrt/include/group.h              |  25 +
  drivers/fpga/xrt/include/metadata.h           | 236 +++++
  drivers/fpga/xrt/include/subdev_id.h          |  39 +
  drivers/fpga/xrt/include/xclbin-helper.h      |  48 +
  drivers/fpga/xrt/include/xdevice.h            | 131 +++
  drivers/fpga/xrt/include/xleaf.h              | 205 +++++
  drivers/fpga/xrt/include/xleaf/axigate.h      |  23 +
  drivers/fpga/xrt/include/xleaf/clkfreq.h      |  21 +
  drivers/fpga/xrt/include/xleaf/clock.h        |  29 +
  .../fpga/xrt/include/xleaf/ddr_calibration.h  |  28 +
  drivers/fpga/xrt/include/xleaf/devctl.h       |  40 +
  drivers/fpga/xrt/include/xleaf/icap.h         |  27 +
  drivers/fpga/xrt/include/xmgmt-main.h         |  34 +
  drivers/fpga/xrt/include/xroot.h              | 117 +++
  drivers/fpga/xrt/lib/Kconfig                  |  17 +
  drivers/fpga/xrt/lib/Makefile                 |  30 +
  drivers/fpga/xrt/lib/cdev.c                   | 209 +++++
  drivers/fpga/xrt/lib/group.c                  | 278 ++++++
  drivers/fpga/xrt/lib/lib-drv.c                | 328 +++++++
  drivers/fpga/xrt/lib/lib-drv.h                |  21 +
  drivers/fpga/xrt/lib/subdev.c                 | 859 +++++++++++++++++
  drivers/fpga/xrt/lib/subdev_pool.h            |  53 ++
  drivers/fpga/xrt/lib/xclbin.c                 | 381 ++++++++
  drivers/fpga/xrt/lib/xleaf/axigate.c          | 325 +++++++
  drivers/fpga/xrt/lib/xleaf/clkfreq.c          | 223 +++++
  drivers/fpga/xrt/lib/xleaf/clock.c            | 652 +++++++++++++
  drivers/fpga/xrt/lib/xleaf/ddr_calibration.c  | 210 +++++
  drivers/fpga/xrt/lib/xleaf/devctl.c           | 169 ++++
  drivers/fpga/xrt/lib/xleaf/icap.c             | 328 +++++++
  drivers/fpga/xrt/lib/xleaf/ucs.c              | 152 +++
  drivers/fpga/xrt/lib/xleaf/vsec.c             | 372 ++++++++
  drivers/fpga/xrt/lib/xroot.c                  | 536 +++++++++++
  drivers/fpga/xrt/metadata/Kconfig             |  12 +
  drivers/fpga/xrt/metadata/Makefile            |  16 +
  drivers/fpga/xrt/metadata/metadata.c          | 578 ++++++++++++
  drivers/fpga/xrt/mgmt/Kconfig                 |  15 +
  drivers/fpga/xrt/mgmt/Makefile                |  19 +
  drivers/fpga/xrt/mgmt/root.c                  | 420 +++++++++
  drivers/fpga/xrt/mgmt/xmgmt-main-region.c     | 483 ++++++++++
  drivers/fpga/xrt/mgmt/xmgmt-main.c            | 662 +++++++++++++
  drivers/fpga/xrt/mgmt/xmgmt.h                 |  33 +
  drivers/fpga/xrt/mgmt/xrt-mgr.c               | 190 ++++
  drivers/fpga/xrt/mgmt/xrt-mgr.h               |  16 +
  include/uapi/linux/xrt/xclbin.h               | 409 ++++++++
  include/uapi/linux/xrt/xmgmt-ioctl.h          |  46 +
  53 files changed, 9988 insertions(+)
  create mode 100644 Documentation/fpga/xrt.rst
  create mode 100644 drivers/fpga/xrt/Kconfig
  create mode 100644 drivers/fpga/xrt/include/events.h
  create mode 100644 drivers/fpga/xrt/include/group.h
  create mode 100644 drivers/fpga/xrt/include/metadata.h
  create mode 100644 drivers/fpga/xrt/include/subdev_id.h
  create mode 100644 drivers/fpga/xrt/include/xclbin-helper.h
  create mode 100644 drivers/fpga/xrt/include/xdevice.h
  create mode 100644 drivers/fpga/xrt/include/xleaf.h
  create mode 100644 drivers/fpga/xrt/include/xleaf/axigate.h
  create mode 100644 drivers/fpga/xrt/include/xleaf/clkfreq.h
  create mode 100644 drivers/fpga/xrt/include/xleaf/clock.h
  create mode 100644 drivers/fpga/xrt/include/xleaf/ddr_calibration.h
  create mode 100644 drivers/fpga/xrt/include/xleaf/devctl.h
  create mode 100644 drivers/fpga/xrt/include/xleaf/icap.h
  create mode 100644 drivers/fpga/xrt/include/xmgmt-main.h
  create mode 100644 drivers/fpga/xrt/include/xroot.h
  create mode 100644 drivers/fpga/xrt/lib/Kconfig
  create mode 100644 drivers/fpga/xrt/lib/Makefile
  create mode 100644 drivers/fpga/xrt/lib/cdev.c
  create mode 100644 drivers/fpga/xrt/lib/group.c
  create mode 100644 drivers/fpga/xrt/lib/lib-drv.c
  create mode 100644 drivers/fpga/xrt/lib/lib-drv.h
  create mode 100644 drivers/fpga/xrt/lib/subdev.c
  create mode 100644 drivers/fpga/xrt/lib/subdev_pool.h
  create mode 100644 drivers/fpga/xrt/lib/xclbin.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/axigate.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/clkfreq.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/clock.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/ddr_calibration.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/devctl.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/icap.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/ucs.c
  create mode 100644 drivers/fpga/xrt/lib/xleaf/vsec.c
  create mode 100644 drivers/fpga/xrt/lib/xroot.c
  create mode 100644 drivers/fpga/xrt/metadata/Kconfig
  create mode 100644 drivers/fpga/xrt/metadata/Makefile
  create mode 100644 drivers/fpga/xrt/metadata/metadata.c
  create mode 100644 drivers/fpga/xrt/mgmt/Kconfig
  create mode 100644 drivers/fpga/xrt/mgmt/Makefile
  create mode 100644 drivers/fpga/xrt/mgmt/root.c
  create mode 100644 drivers/fpga/xrt/mgmt/xmgmt-main-region.c
  create mode 100644 drivers/fpga/xrt/mgmt/xmgmt-main.c
  create mode 100644 drivers/fpga/xrt/mgmt/xmgmt.h
  create mode 100644 drivers/fpga/xrt/mgmt/xrt-mgr.c
  create mode 100644 drivers/fpga/xrt/mgmt/xrt-mgr.h
  create mode 100644 include/uapi/linux/xrt/xclbin.h
  create mode 100644 include/uapi/linux/xrt/xmgmt-ioctl.h