[dpdk-dev] [PATCH v2 2/3] doc/guides: documentation for the FPGA BBDEV PMD

Nicolas Chautru nicolas.chautru at intel.com
Wed Jun 5 23:20:59 CEST 2019


Adding documentation related to the new PMD driver
in previous commit

Signed-off-by: Nicolas Chautru <nicolas.chautru at intel.com>
---
 doc/guides/bbdevs/fpga_lte_fec.rst | 318 +++++++++++++++++++++++++++++++++++++
 doc/guides/bbdevs/index.rst        |   1 +
 2 files changed, 319 insertions(+)
 create mode 100644 doc/guides/bbdevs/fpga_lte_fec.rst

diff --git a/doc/guides/bbdevs/fpga_lte_fec.rst b/doc/guides/bbdevs/fpga_lte_fec.rst
new file mode 100644
index 0000000..71b058c
--- /dev/null
+++ b/doc/guides/bbdevs/fpga_lte_fec.rst
@@ -0,0 +1,318 @@
+..  SPDX-License-Identifier: BSD-3-Clause
+    Copyright(c) 2018 Intel Corporation
+
+Intel(R) FPGA LTE FEC Poll Mode Driver
+======================================
+
+The BBDEV FPGA LTE FEC poll mode driver (PMD) supports an FPGA implementation of a VRAN
+Turbo Encode / Decode LTE wireless acceleration function, using Intel's PCI-e and FPGA
+based Vista Creek device.
+
+Features
+--------
+
+FPGA LTE FEC PMD supports the following features:
+
+- Turbo Encode in the DL with total throughput of 4.5 Gbits/s
+- Turbo Decode in the UL with total throughput of 1.5 Gbits/s assuming 8 decoder iterations
+- 8 VFs per PF (physical device)
+- Maximum of 32 UL queues per VF
+- Maximum of 32 DL queues per VF
+- PCIe Gen-3 x8 Interface
+- MSI-X
+- SR-IOV
+
+
+FPGA LTE FEC PMD supports the following BBDEV capabilities:
+
+* For the turbo encode operation:
+   - ``RTE_BBDEV_TURBO_CRC_24B_ATTACH`` :  set to attach CRC24B to CB(s)
+   - ``RTE_BBDEV_TURBO_RATE_MATCH`` :  if set then do not do Rate Match bypass
+   - ``RTE_BBDEV_TURBO_ENC_INTERRUPTS`` :  set for encoder dequeue interrupts
+
+
+* For the turbo decode operation:
+   - ``RTE_BBDEV_TURBO_CRC_TYPE_24B`` :  check CRC24B from CB(s)
+   - ``RTE_BBDEV_TURBO_SUBBLOCK_DEINTERLEAVE`` :  perform subblock de-interleave
+   - ``RTE_BBDEV_TURBO_DEC_INTERRUPTS`` :  set for decoder dequeue interrupts
+   - ``RTE_BBDEV_TURBO_NEG_LLR_1_BIT_IN`` :  set if negative LLR encoder i/p is supported
+   - ``RTE_BBDEV_TURBO_DEC_TB_CRC_24B_KEEP`` :  keep CRC24B bits appended while decoding
+
+
+Limitations
+-----------
+
+FPGA LTE FEC does not support the following:
+
+- Scatter-Gather function
+
+
+Installation
+--------------
+
+Section 3 of the DPDK manual provides instuctions on installing and compiling DPDK. The
+default set of bbdev compile flags may be found in config/common_base, where for example
+the flag to build the FPGA LTE FEC device, ``CONFIG_RTE_LIBRTE_PMD_FPGA_LTE_FEC``, is already
+set. It is assumed DPDK has been compiled using for instance:
+
+.. code-block:: console
+
+  make install T=x86_64-native-linuxapp-gcc
+
+
+DPDK requires hugepages to be configured as detailed in section 2 of the DPDK manual.
+The bbdev test application has been tested with a configuration 40 x 1GB hugepages. The
+hugepage configuration of a server may be examined using:
+
+.. code-block:: console
+
+   grep Huge* /proc/meminfo
+
+
+Initialization
+--------------
+
+When the device first powers up, its PCI Physical Functions (PF) can be listed through this command:
+
+.. code-block:: console
+
+  sudo lspci -vd1172:5052
+
+The physical and virtual functions are compatible with Linux UIO drivers:
+``vfio`` and ``igb_uio``. However, in order to work the FPGA LTE FEC device firstly needs
+to be bound to one of these linux drivers through DPDK.
+
+
+Bind PF UIO driver(s)
+~~~~~~~~~~~~~~~~~~~~~
+
+Install the DPDK igb_uio driver, bind it with the PF PCI device ID and use
+``lspci`` to confirm the PF device is under use by ``igb_uio`` DPDK UIO driver.
+
+The igb_uio driver may be bound to the PF PCI device using one of three methods:
+
+
+1. PCI functions (physical or virtual, depending on the use case) can be bound to
+the UIO driver by repeating this command for every function.
+
+.. code-block:: console
+
+  cd <dpdk-top-level-directory>
+  insmod ./build/kmod/igb_uio.ko
+  echo "1172 5052" > /sys/bus/pci/drivers/igb_uio/new_id
+  lspci -vd1172:
+
+
+2. Another way to bind PF with DPDK UIO driver is by using the ``dpdk-devbind.py`` tool
+
+.. code-block:: console
+
+  cd <dpdk-top-level-directory>
+  ./usertools/dpdk-devbind.py -b igb_uio 0000:06:00.0
+
+where the PCI device ID (example: 0000:06:00.0) is obtained using lspci -vd1172:
+
+
+3. A third way to bind is to use ``dpdk-setup.sh`` tool
+
+.. code-block:: console
+
+  cd <dpdk-top-level-directory>
+  ./usertools/dpdk-setup.sh
+
+  select 'Bind Ethernet/Crypto/Baseband device to IGB UIO module'
+  or
+  select 'Bind Ethernet/Crypto/Baseband device to VFIO module' depending on driver required
+  enter PCI device ID
+  select 'Display current Ethernet/Crypto/Baseband device settings' to confirm binding
+
+
+In the same way the FPGA LTE FEC PF can be bound with vfio, but vfio driver does not
+support SR-IOV configuration right out of the box, so it will need to be patched.
+
+
+Enable Virtual Functions
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Now, it should be visible in the printouts that PCI PF is under igb_uio control
+"``Kernel driver in use: igb_uio``"
+
+To show the number of available VFs on the device, read ``sriov_totalvfs`` file..
+
+.. code-block:: console
+
+  cat /sys/bus/pci/devices/0000\:<b>\:<d>.<f>/sriov_totalvfs
+
+  where 0000\:<b>\:<d>.<f> is the PCI device ID
+
+
+To enable VFs via igb_uio, echo the number of virtual functions intended to
+enable to ``max_vfs`` file..
+
+.. code-block:: console
+
+  echo <num-of-vfs> > /sys/bus/pci/devices/0000\:<b>\:<d>.<f>/max_vfs
+
+
+Afterwards, all VFs must be bound to appropriate UIO drivers as required, same
+way it was done with the physical function previously.
+
+Enabling SR-IOV via vfio driver is pretty much the same, except that the file
+name is different:
+
+.. code-block:: console
+
+  echo <num-of-vfs> > /sys/bus/pci/devices/0000\:<b>\:<d>.<f>/sriov_numvfs
+
+
+Configure the VFs through PF
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The PCI virtual functions must be configured before working or getting assigned
+to VMs/Containers. The configuration involves allocating the number of hardware
+queues, priorities, load balance, bandwidth and other settings necessary for the
+device to perform FEC functions.
+
+This configuration needs to be executed at least once after reboot or PCI FLR and can
+be achieved by using the function ``fpga_lte_fec_configure()``, which sets up the
+parameters defined in ``fpga_lte_fec_conf`` structure:
+
+.. code-block:: c
+
+  struct fpga_lte_fec_conf {
+      bool pf_mode_en;
+      uint8_t vf_ul_queues_number[FPGA_LTE_FEC_NUM_VFS];
+      uint8_t vf_dl_queues_number[FPGA_LTE_FEC_NUM_VFS];
+      uint8_t ul_bandwidth;
+      uint8_t dl_bandwidth;
+      uint8_t ul_load_balance;
+      uint8_t dl_load_balance;
+      uint16_t flr_time_out;
+  };
+
+- ``pf_mode_en``: identifies whether only PF is to be used, or the VFs. PF and
+  VFs are mutually exclusive and cannot run simultaneously.
+  Set to 1 for PF mode enabled.
+  If PF mode is enabled all queues available in the device are assigned
+  exclusively to PF and 0 queues given to VFs.
+
+- ``vf_*l_queues_number``: defines the hardware queue mapping for every VF.
+
+- ``*l_bandwidth``: in case of congestion on PCIe interface. The device
+  allocates different bandwidth to UL and DL. The weight is configured by this
+  setting. The unit of weight is 3 code blocks. For example, if the code block
+  cbps (code block per second) ratio between UL and DL is 12:1, then the
+  configuration value should be set to 36:3. The schedule algorithm is based
+  on code block regardless the length of each block.
+
+- ``*l_load_balance``: hardware queues are load-balanced in a round-robin
+  fashion. Queues get filled first-in first-out until they reach a pre-defined
+  watermark level, if exceeded, they won't get assigned new code blocks..
+  This watermark is defined by this setting.
+
+  If all hardware queues exceeds the watermark, no code blocks will be
+  streamed in from UL/DL code block FIFO.
+
+- ``flr_time_out``: specifies how many 16.384us to be FLR time out. The
+  time_out = flr_time_out x 16.384us. For instance, if you want to set 10ms for
+  the FLR time out then set this setting to 0x262=610.
+
+
+An example configuration code calling the function ``fpga_lte_fec_configure()`` is shown
+below:
+
+.. code-block:: c
+
+  struct fpga_lte_fec_conf conf;
+  unsigned int i;
+
+  memset(&conf, 0, sizeof(struct fpga_lte_fec_conf));
+  conf.pf_mode_en = 1;
+
+  for (i = 0; i < FPGA_LTE_FEC_NUM_VFS; ++i) {
+      conf.vf_ul_queues_number[i] = 4;
+      conf.vf_dl_queues_number[i] = 4;
+  }
+  conf.ul_bandwidth = 12;
+  conf.dl_bandwidth = 5;
+  conf.dl_load_balance = 64;
+  conf.ul_load_balance = 64;
+
+  /* setup FPGA PF */
+  ret = fpga_lte_fec_configure(info->dev_name, &conf);
+  TEST_ASSERT_SUCCESS(ret,
+      "Failed to configure 4G FPGA PF for bbdev %s",
+      info->dev_name);
+
+
+Test Application
+----------------
+
+BBDEV provides a test application, ``test-bbdev.py`` and range of test data for testing
+the functionality of FPGA LTE FEC turbo encode and turbo decode, depending on the device's
+capabilities. The test application is located under app->test-bbdev folder and has the
+following options:
+
+.. code-block:: console
+
+  "-p", "--testapp-path": specifies path to the bbdev test app.
+  "-e", "--eal-params"	: EAL arguments which are passed to the test app.
+  "-t", "--timeout"	: Timeout in seconds (default=300).
+  "-c", "--test-cases"	: Defines test cases to run. Run all if not specified.
+  "-v", "--test-vector"	: Test vector path (default=dpdk_path+/app/test-bbdev/test_vectors/bbdev_null.data).
+  "-n", "--num-ops"	: Number of operations to process on device (default=32).
+  "-b", "--burst-size"	: Operations enqueue/dequeue burst size (default=32).
+  "-l", "--num-lcores"	: Number of lcores to run (default=16).
+  "-i", "--init-device" : Initialise PF device with default values.
+
+
+To execute the test application tool using simple turbo decode or turbo encode data,
+type one of the following:
+
+.. code-block:: console
+
+  ./test-bbdev.py -c validation -n 64 -b 8 -v ./turbo_dec_default.data
+  ./test-bbdev.py -c validation -n 64 -b 8 -v ./turbo_enc_default.data
+
+
+The test application ``test-bbdev.py``, supports the ability to configure the PF device with
+a default set of values, if the "-i" or "- -init-device" option is included. The default values
+are defined in test_bbdev_perf.c as:
+
+- VF_UL_QUEUE_VALUE 4
+- VF_DL_QUEUE_VALUE 4
+- UL_BANDWIDTH 3
+- DL_BANDWIDTH 3
+- UL_LOAD_BALANCE 128
+- DL_LOAD_BALANCE 128
+- FLR_TIMEOUT 610
+
+
+Test Vectors
+~~~~~~~~~~~~
+
+In addition to the simple turbo decoder and turbo encoder tests, bbdev also provides
+a range of additional tests under the test_vectors folder, which may be useful. The results
+of these tests will depend on the FPGA LTE FEC capabilities:
+
+* turbo decoder tests:
+   - ``turbo_dec_c1_k6144_r0_e10376_crc24b_sbd_negllr_high_snr.data``
+   - ``turbo_dec_c1_k6144_r0_e10376_crc24b_sbd_negllr_low_snr.data``
+   - ``turbo_dec_c1_k6144_r0_e34560_negllr.data``
+   - ``turbo_dec_c1_k6144_r0_e34560_sbd_negllr.data``
+   - ``turbo_dec_c2_k3136_r0_e4920_sbd_negllr_crc24b.data``
+   - ``turbo_dec_c2_k3136_r0_e4920_sbd_negllr.data``
+
+
+* turbo encoder tests:
+   - ``turbo_enc_c1_k40_r0_e1190_rm.data``
+   - ``turbo_enc_c1_k40_r0_e1194_rm.data``
+   - ``turbo_enc_c1_k40_r0_e1196_rm.data``
+   - ``turbo_enc_c1_k40_r0_e272_rm.data``
+   - ``turbo_enc_c1_k6144_r0_e18444.data``
+   - ``turbo_enc_c1_k6144_r0_e32256_crc24b_rm.data``
+   - ``turbo_enc_c2_k5952_r0_e17868_crc24b.data``
+   - ``turbo_enc_c3_k4800_r2_e14412_crc24b.data``
+   - ``turbo_enc_c4_k4800_r2_e14412_crc24b.data``
+
+
diff --git a/doc/guides/bbdevs/index.rst b/doc/guides/bbdevs/index.rst
index 93276ed..005b95e 100644
--- a/doc/guides/bbdevs/index.rst
+++ b/doc/guides/bbdevs/index.rst
@@ -10,3 +10,4 @@ Baseband Device Drivers
 
     null
     turbo_sw
+    fpga_lte_fec
-- 
1.8.3.1



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