preface
The common igb electric interface network card needs to support the configuration of rate duplex, but the interface of rate duplex is not configured in dpdk-19.11. Therefore, it needs to be developed, and the implementation method needs to be determined by studying the driver codes of different network cards.
In this paper, the igb network card driver is described as an example.
Research on igb network card driver
The IGB network card driver in dpdk-19.11 is executing eth_ igb_ Duplex rate will be configured when starting up the interface.
The relevant codes are as follows:
1349 /* Setup link speed and duplex */
1350 speeds = &dev->data->dev_conf.link_speeds;
1351 if (*speeds == ETH_LINK_SPEED_AUTONEG) {
1352 hw->phy.autoneg_advertised = E1000_ALL_SPEED_DUPLEX;
1353 hw->mac.autoneg = 1;
1354 } else {
1355 num_speeds = 0;
1356 autoneg = (*speeds & ETH_LINK_SPEED_FIXED) == 0;
1357
1358 /* Reset */
1359 hw->phy.autoneg_advertised = 0;
1360
1361 if (*speeds & ~(ETH_LINK_SPEED_10M_HD | ETH_LINK_SPEED_10M |
1362 ETH_LINK_SPEED_100M_HD | ETH_LINK_SPEED_100M |
1363 ETH_LINK_SPEED_1G | ETH_LINK_SPEED_FIXED)) {
1364 num_speeds = -1;
1365 goto error_invalid_config;
1366 }
1367 if (*speeds & ETH_LINK_SPEED_10M_HD) {
1368 hw->phy.autoneg_advertised |= ADVERTISE_10_HALF;
1369 num_speeds++;
1370 }
...............
1387 if (num_speeds == 0 || (!autoneg && (num_speeds > 1)))
1388 goto error_invalid_config;
1389
1390 /* Set/reset the mac.autoneg based on the link speed,
1391 * fixed or not
1392 */
1393 if (!autoneg) {
1394 hw->mac.autoneg = 0;
1395 hw->mac.forced_speed_duplex =
1396 hw->phy.autoneg_advertised;
1397 } else {
1398 hw->mac.autoneg = 1;
1399 }
1402 e1000_setup_link(hw);
The main logic of the above code is as follows:
- Get dev - > Data - > dev_ conf.link_ Link set in speeds variable_ Speeds to obtain the duplex configuration status of the rate
- According to link_ The value of the speeds variable is set to drive internal variables, such as HW - > PHY autoneg_ advertised,hw->mac. autoneg,hw->mac. forced_ speed_ Value of duplex
- Call e1000_setup_link configure the set duplex rate
According to the above process, we only need to set dev - > Data - > dev_ conf.link_ Speed, and then up the interface again to realize the rate duplex configuration.
Test verification process
After the above analysis, the method of speed duplex configuration of igb network card has been determined, and the feasibility needs to be verified.
Can be in E1000_ setup_ Execute the following code before calling the link function:
hw->mac.autoneg = 0; hw->mac.forced_speed_duplex = ADVERTISE_100_FULL;
These two lines of code configure the interface rate duplex to force 100M full duplex. After modifying the code, use the kni program to test. The opposite interface is bound to the kernel driver. The test is valid!
Default rate duplex configuration of igb network card
After the setting scheme is determined, you cannot forget the default rate duplex configuration item of the igb network card. Generally speaking, in China_ eth_ dev_ Configure failed dev_conf setting link_ The value of speeds defaults to 0.
eth_ igb_ dev_ The following code in the init function configures the interface to use the self negotiation mode, and specifies the negotiation rate as all supported rates and duplex mode.
793 hw->mac.autoneg = 1; 794 hw->phy.autoneg_wait_to_complete = 0; 795 hw->phy.autoneg_advertised = E1000_ALL_SPEED_DUPLEX;
dpdk-19.11 get the rate duplex configuration supported by the interface
Before setting the duplex rate, you can add some checks to check whether the mode to be set is supported by the current network card. You can call rte_eth_dev_info_get function to get dev_info structure, dev_ Speed in info structure_ The CAPA field represents the rate duplex configuration supported by the current network card.
For IGB network card, speed_capa field via eth_ igb_ infos_ The get function is filled with the following code:
2286 dev_info->speed_capa = ETH_LINK_SPEED_10M_HD | ETH_LINK_SPEED_10M | 2287 ETH_LINK_SPEED_100M_HD | ETH_LINK_SPEED_100M | 2288 ETH_LINK_SPEED_1G;
After you get it, you can check it!
summary
Taking igb driver as an example, this paper describes the method of dpdk-19.11 supporting interface configuration rate duplex. This method is suitable for multiple drivers and is a relatively general method. Rate duplex configuration is also a common function that the network card driver should provide externally. However, the processing process of dpdk here is somewhat special. It focuses the configuration on dev - > Data - > dev_ conf.link_ The speed variable is set!