[dpdk-dev] Port link speed and link duplex always set to auto-negotiate & manual link speed configuration of 100Mb link speed not possible

["Marc E. Cooper" <mcooper@hexiscyber.com>]

I believe there are defects in the code supporting manual configuration of
port link speed and link duplex to values other than auto-negotiate.  The
TESTPMD application from DPDK version 1.8.0 was executed on 2 different
systems having 4x1G NICs with the following Ethernet controllers:

* Intel Corporation 82576 Gigabit Network Connection (rev 01)
* Intel Corporation I350 Gigabit Network Connection (rev 01)

There appears to be two issues in the code:

* "hw->mac.autoneg² is always set to true (1).  The force speed and duplex
code path is not followed.
* "hw->mac.forced_speed_duplex" is never set.  A forced link speed
configuration will always default to 10Mb regardless of whether configured
for 100Mb or 10Mb.  For example, e1000_phy_force_speed_duplex_setup() will
always configure link speed to 10mb since it checks for the following
condition "if (mac->forced_speed_duplex & E1000_ALL_100_SPEED)².

Changes are needed within ³igb_ethdev.c² and ³em_ethdev.c² within
³lib/librte_pmd_e1000².  The switch statements that setup link speed and
link duplex within these files need to manually set "hw->mac.autoneg" and
"hw->mac.forced_speed_duplex" as shown below:

[root@box librte_pmd_e1000]# pwd
/home/marc/dpdk/dpdk-1.8.0/lib/librte_pmd_e1000
[root@box librte_pmd_e1000]# diff  -p igb_ethdev.c.orig igb_ethdev.c
*** igb_ethdev.c.orig	2015-01-08 09:59:52.937215791 -0500
--- igb_ethdev.c	2015-01-08 10:01:44.073730592 -0500
*************** eth_igb_start(struct rte_eth_dev *dev)
*** 871,876 ****
--- 871,878 ----
  			hw->phy.autoneg_advertised = ADVERTISE_10_FULL;
  		else
  			goto error_invalid_config;
+               hw->mac.autoneg = 0;
+               hw->mac.forced_speed_duplex |= hw->phy.autoneg_advertised;
  		break;
  	case ETH_LINK_SPEED_100:
  		if (dev->data->dev_conf.link_duplex == ETH_LINK_AUTONEG_DUPLEX)
*************** eth_igb_start(struct rte_eth_dev *dev)
*** 881,886 ****
--- 883,890 ----
  			hw->phy.autoneg_advertised = ADVERTISE_100_FULL;
  		else
  			goto error_invalid_config;
+               hw->mac.autoneg = 0;
+               hw->mac.forced_speed_duplex |= hw->phy.autoneg_advertised;
  		break;
  	case ETH_LINK_SPEED_1000:
  		if ((dev->data->dev_conf.link_duplex == ETH_LINK_AUTONEG_DUPLEX) ||
*************** eth_igb_start(struct rte_eth_dev *dev)
*** 888,893 ****
--- 892,899 ----
  			hw->phy.autoneg_advertised = ADVERTISE_1000_FULL;
  		else
  			goto error_invalid_config;
+               hw->mac.autoneg = 0;
+               hw->mac.forced_speed_duplex |= hw->phy.autoneg_advertised;
  		break;
  	case ETH_LINK_SPEED_10000:
  	default:
[root@box librte_pmd_e1000]#


After only setting hw->mac.autoneg = 0 in the switch statement cases
described above I experimented with configuring the peer (switch) ports
for 100Mb full duplex.  Within TESTPMD the ports were also configured for
100Mb full duplex using ³port config all speed 100 duplex full².  The
links failed to establish.  I enabled debug statements within
³e1000_phy_force_speed_duplex_setup()² found in
³lib/librte_pmd_e1000/e1000/e1000_phy.c² to display whether 100mb or 10mb
was being forced.  It was observed that 10Mb was being forced when the
link speed was manually configured for 100Mb.  Setting
³hw->mac.force_speed_duplex² as shown above seemed to resolve this issue
and the links came up.
 

Are these known issues?

-Marc