xref: /dpdk/doc/guides/bbdevs/fpga_lte_fec.rst (revision 1cde1b9a9b4dbf31cb5e5ccdfc5da3cb079f43a2)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2019 Intel Corporation
3
4Intel(R) FPGA LTE FEC Poll Mode Driver
5======================================
6
7The BBDEV FPGA LTE FEC poll mode driver (PMD) supports an FPGA implementation of a VRAN
8Turbo Encode / Decode LTE wireless acceleration function, using Intel's PCI-e and FPGA
9based Vista Creek device.
10
11Features
12--------
13
14FPGA LTE FEC PMD supports the following features:
15
16- Turbo Encode in the DL with total throughput of 4.5 Gbits/s
17- Turbo Decode in the UL with total throughput of 1.5 Gbits/s assuming 8 decoder iterations
18- 8 VFs per PF (physical device)
19- Maximum of 32 UL queues per VF
20- Maximum of 32 DL queues per VF
21- PCIe Gen-3 x8 Interface
22- MSI-X
23- SR-IOV
24
25
26FPGA LTE FEC PMD supports the following BBDEV capabilities:
27
28* For the turbo encode operation:
29   - ``RTE_BBDEV_TURBO_CRC_24B_ATTACH`` :  set to attach CRC24B to CB(s)
30   - ``RTE_BBDEV_TURBO_RATE_MATCH`` :  if set then do not do Rate Match bypass
31   - ``RTE_BBDEV_TURBO_ENC_INTERRUPTS`` :  set for encoder dequeue interrupts
32
33
34* For the turbo decode operation:
35   - ``RTE_BBDEV_TURBO_CRC_TYPE_24B`` :  check CRC24B from CB(s)
36   - ``RTE_BBDEV_TURBO_SUBBLOCK_DEINTERLEAVE`` :  perform subblock de-interleave
37   - ``RTE_BBDEV_TURBO_DEC_INTERRUPTS`` :  set for decoder dequeue interrupts
38   - ``RTE_BBDEV_TURBO_NEG_LLR_1_BIT_IN`` :  set if negative LLR encoder i/p is supported
39   - ``RTE_BBDEV_TURBO_DEC_TB_CRC_24B_KEEP`` :  keep CRC24B bits appended while decoding
40
41
42Limitations
43-----------
44
45FPGA LTE FEC does not support the following:
46
47- Scatter-Gather function
48
49
50Installation
51--------------
52
53Section 3 of the DPDK manual provides instuctions on installing and compiling DPDK. The
54default set of bbdev compile flags may be found in config/common_base, where for example
55the flag to build the FPGA LTE FEC device, ``CONFIG_RTE_LIBRTE_PMD_BBDEV_FPGA_LTE_FEC``, is already
56set. It is assumed DPDK has been compiled using for instance:
57
58.. code-block:: console
59
60  make install T=x86_64-native-linuxapp-gcc
61
62
63DPDK requires hugepages to be configured as detailed in section 2 of the DPDK manual.
64The bbdev test application has been tested with a configuration 40 x 1GB hugepages. The
65hugepage configuration of a server may be examined using:
66
67.. code-block:: console
68
69   grep Huge* /proc/meminfo
70
71
72Initialization
73--------------
74
75When the device first powers up, its PCI Physical Functions (PF) can be listed through this command:
76
77.. code-block:: console
78
79  sudo lspci -vd1172:5052
80
81The physical and virtual functions are compatible with Linux UIO drivers:
82``vfio`` and ``igb_uio``. However, in order to work the FPGA LTE FEC device firstly needs
83to be bound to one of these linux drivers through DPDK.
84
85
86Bind PF UIO driver(s)
87~~~~~~~~~~~~~~~~~~~~~
88
89Install the DPDK igb_uio driver, bind it with the PF PCI device ID and use
90``lspci`` to confirm the PF device is under use by ``igb_uio`` DPDK UIO driver.
91
92The igb_uio driver may be bound to the PF PCI device using one of three methods:
93
94
951. PCI functions (physical or virtual, depending on the use case) can be bound to
96the UIO driver by repeating this command for every function.
97
98.. code-block:: console
99
100  cd <dpdk-top-level-directory>
101  insmod ./build/kmod/igb_uio.ko
102  echo "1172 5052" > /sys/bus/pci/drivers/igb_uio/new_id
103  lspci -vd1172:
104
105
1062. Another way to bind PF with DPDK UIO driver is by using the ``dpdk-devbind.py`` tool
107
108.. code-block:: console
109
110  cd <dpdk-top-level-directory>
111  ./usertools/dpdk-devbind.py -b igb_uio 0000:06:00.0
112
113where the PCI device ID (example: 0000:06:00.0) is obtained using lspci -vd1172:
114
115
1163. A third way to bind is to use ``dpdk-setup.sh`` tool
117
118.. code-block:: console
119
120  cd <dpdk-top-level-directory>
121  ./usertools/dpdk-setup.sh
122
123  select 'Bind Ethernet/Crypto/Baseband device to IGB UIO module'
124  or
125  select 'Bind Ethernet/Crypto/Baseband device to VFIO module' depending on driver required
126  enter PCI device ID
127  select 'Display current Ethernet/Crypto/Baseband device settings' to confirm binding
128
129
130In the same way the FPGA LTE FEC PF can be bound with vfio, but vfio driver does not
131support SR-IOV configuration right out of the box, so it will need to be patched.
132
133
134Enable Virtual Functions
135~~~~~~~~~~~~~~~~~~~~~~~~
136
137Now, it should be visible in the printouts that PCI PF is under igb_uio control
138"``Kernel driver in use: igb_uio``"
139
140To show the number of available VFs on the device, read ``sriov_totalvfs`` file..
141
142.. code-block:: console
143
144  cat /sys/bus/pci/devices/0000\:<b>\:<d>.<f>/sriov_totalvfs
145
146  where 0000\:<b>\:<d>.<f> is the PCI device ID
147
148
149To enable VFs via igb_uio, echo the number of virtual functions intended to
150enable to ``max_vfs`` file..
151
152.. code-block:: console
153
154  echo <num-of-vfs> > /sys/bus/pci/devices/0000\:<b>\:<d>.<f>/max_vfs
155
156
157Afterwards, all VFs must be bound to appropriate UIO drivers as required, same
158way it was done with the physical function previously.
159
160Enabling SR-IOV via vfio driver is pretty much the same, except that the file
161name is different:
162
163.. code-block:: console
164
165  echo <num-of-vfs> > /sys/bus/pci/devices/0000\:<b>\:<d>.<f>/sriov_numvfs
166
167
168Configure the VFs through PF
169~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
170
171The PCI virtual functions must be configured before working or getting assigned
172to VMs/Containers. The configuration involves allocating the number of hardware
173queues, priorities, load balance, bandwidth and other settings necessary for the
174device to perform FEC functions.
175
176This configuration needs to be executed at least once after reboot or PCI FLR and can
177be achieved by using the function ``fpga_lte_fec_configure()``, which sets up the
178parameters defined in ``fpga_lte_fec_conf`` structure:
179
180.. code-block:: c
181
182  struct fpga_lte_fec_conf {
183      bool pf_mode_en;
184      uint8_t vf_ul_queues_number[FPGA_LTE_FEC_NUM_VFS];
185      uint8_t vf_dl_queues_number[FPGA_LTE_FEC_NUM_VFS];
186      uint8_t ul_bandwidth;
187      uint8_t dl_bandwidth;
188      uint8_t ul_load_balance;
189      uint8_t dl_load_balance;
190      uint16_t flr_time_out;
191  };
192
193- ``pf_mode_en``: identifies whether only PF is to be used, or the VFs. PF and
194  VFs are mutually exclusive and cannot run simultaneously.
195  Set to 1 for PF mode enabled.
196  If PF mode is enabled all queues available in the device are assigned
197  exclusively to PF and 0 queues given to VFs.
198
199- ``vf_*l_queues_number``: defines the hardware queue mapping for every VF.
200
201- ``*l_bandwidth``: in case of congestion on PCIe interface. The device
202  allocates different bandwidth to UL and DL. The weight is configured by this
203  setting. The unit of weight is 3 code blocks. For example, if the code block
204  cbps (code block per second) ratio between UL and DL is 12:1, then the
205  configuration value should be set to 36:3. The schedule algorithm is based
206  on code block regardless the length of each block.
207
208- ``*l_load_balance``: hardware queues are load-balanced in a round-robin
209  fashion. Queues get filled first-in first-out until they reach a pre-defined
210  watermark level, if exceeded, they won't get assigned new code blocks..
211  This watermark is defined by this setting.
212
213  If all hardware queues exceeds the watermark, no code blocks will be
214  streamed in from UL/DL code block FIFO.
215
216- ``flr_time_out``: specifies how many 16.384us to be FLR time out. The
217  time_out = flr_time_out x 16.384us. For instance, if you want to set 10ms for
218  the FLR time out then set this setting to 0x262=610.
219
220
221An example configuration code calling the function ``fpga_lte_fec_configure()`` is shown
222below:
223
224.. code-block:: c
225
226  struct fpga_lte_fec_conf conf;
227  unsigned int i;
228
229  memset(&conf, 0, sizeof(struct fpga_lte_fec_conf));
230  conf.pf_mode_en = 1;
231
232  for (i = 0; i < FPGA_LTE_FEC_NUM_VFS; ++i) {
233      conf.vf_ul_queues_number[i] = 4;
234      conf.vf_dl_queues_number[i] = 4;
235  }
236  conf.ul_bandwidth = 12;
237  conf.dl_bandwidth = 5;
238  conf.dl_load_balance = 64;
239  conf.ul_load_balance = 64;
240
241  /* setup FPGA PF */
242  ret = fpga_lte_fec_configure(info->dev_name, &conf);
243  TEST_ASSERT_SUCCESS(ret,
244      "Failed to configure 4G FPGA PF for bbdev %s",
245      info->dev_name);
246
247
248Test Application
249----------------
250
251BBDEV provides a test application, ``test-bbdev.py`` and range of test data for testing
252the functionality of FPGA LTE FEC turbo encode and turbo decode, depending on the device's
253capabilities. The test application is located under app->test-bbdev folder and has the
254following options:
255
256.. code-block:: console
257
258  "-p", "--testapp-path": specifies path to the bbdev test app.
259  "-e", "--eal-params"	: EAL arguments which are passed to the test app.
260  "-t", "--timeout"	: Timeout in seconds (default=300).
261  "-c", "--test-cases"	: Defines test cases to run. Run all if not specified.
262  "-v", "--test-vector"	: Test vector path (default=dpdk_path+/app/test-bbdev/test_vectors/bbdev_null.data).
263  "-n", "--num-ops"	: Number of operations to process on device (default=32).
264  "-b", "--burst-size"	: Operations enqueue/dequeue burst size (default=32).
265  "-l", "--num-lcores"	: Number of lcores to run (default=16).
266  "-i", "--init-device" : Initialise PF device with default values.
267
268
269To execute the test application tool using simple turbo decode or turbo encode data,
270type one of the following:
271
272.. code-block:: console
273
274  ./test-bbdev.py -c validation -n 64 -b 8 -v ./turbo_dec_default.data
275  ./test-bbdev.py -c validation -n 64 -b 8 -v ./turbo_enc_default.data
276
277
278The test application ``test-bbdev.py``, supports the ability to configure the PF device with
279a default set of values, if the "-i" or "- -init-device" option is included. The default values
280are defined in test_bbdev_perf.c as:
281
282- VF_UL_QUEUE_VALUE 4
283- VF_DL_QUEUE_VALUE 4
284- UL_BANDWIDTH 3
285- DL_BANDWIDTH 3
286- UL_LOAD_BALANCE 128
287- DL_LOAD_BALANCE 128
288- FLR_TIMEOUT 610
289
290
291Test Vectors
292~~~~~~~~~~~~
293
294In addition to the simple turbo decoder and turbo encoder tests, bbdev also provides
295a range of additional tests under the test_vectors folder, which may be useful. The results
296of these tests will depend on the FPGA LTE FEC capabilities:
297
298* turbo decoder tests:
299   - ``turbo_dec_c1_k6144_r0_e10376_crc24b_sbd_negllr_high_snr.data``
300   - ``turbo_dec_c1_k6144_r0_e10376_crc24b_sbd_negllr_low_snr.data``
301   - ``turbo_dec_c1_k6144_r0_e34560_negllr.data``
302   - ``turbo_dec_c1_k6144_r0_e34560_sbd_negllr.data``
303   - ``turbo_dec_c2_k3136_r0_e4920_sbd_negllr_crc24b.data``
304   - ``turbo_dec_c2_k3136_r0_e4920_sbd_negllr.data``
305
306
307* turbo encoder tests:
308   - ``turbo_enc_c1_k40_r0_e1190_rm.data``
309   - ``turbo_enc_c1_k40_r0_e1194_rm.data``
310   - ``turbo_enc_c1_k40_r0_e1196_rm.data``
311   - ``turbo_enc_c1_k40_r0_e272_rm.data``
312   - ``turbo_enc_c1_k6144_r0_e18444.data``
313   - ``turbo_enc_c1_k6144_r0_e32256_crc24b_rm.data``
314   - ``turbo_enc_c2_k5952_r0_e17868_crc24b.data``
315   - ``turbo_enc_c3_k4800_r2_e14412_crc24b.data``
316   - ``turbo_enc_c4_k4800_r2_e14412_crc24b.data``
317