Re: [dpdk-dev] [PATCH 1/2] rte_ethdev: update link status (speed, duplex, link_up) after rte_eth_dev_start

["Zhang, Helin" <helin.zhang@intel.com>]

Hi Jia

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Jia Yu
> Sent: Saturday, November 8, 2014 1:32 AM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH 1/2] rte_ethdev: update link status (speed, duplex,
> link_up) after rte_eth_dev_start
> 
> Since LSR interrupt is disabled by pmd drivers, link status in rte_eth_device is
> always down.
If LSC interrupt is disabled by default, it will poll the link status during the initialization
or in dev_start, and then the link status should he correct. If I am not wrong.

> Bond slave_configure() enables LSR interrupt on devices to get notification if link
> status changes. However, the LSC interrupt at device start time is still lost.
Before enabling interrupt for LSC, the link status should be polled. So after the port
startup, the link status should be there.

> 
> In this fix, call link_update to read link status from hardware register at device
> start time.
Could you help to explain this code changes a bit more? Why we need it?

> 
> Issue:
> Change-Id: Ib57a1c9114f922485c7b0f4338bfe7b3d3f87d65
> Signed-off-by: Jia Yu <jyu@vmware.com>
> ---
>  lib/librte_ether/rte_ethdev.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c index
> ff1c769..6c01b02 100644
> --- a/lib/librte_ether/rte_ethdev.c
> +++ b/lib/librte_ether/rte_ethdev.c
> @@ -869,6 +869,10 @@ rte_eth_dev_start(uint8_t port_id)
> 
>  	rte_eth_dev_config_restore(port_id);
> 
> +	if (dev->data->dev_conf.intr_conf.lsc != 0) {
> +		FUNC_PTR_OR_ERR_RET(*dev->dev_ops->link_update, -ENOTSUP);
> +		(*dev->dev_ops->link_update)(dev, 0);
> +	}
>  	return 0;
>  }
> 
> --
> 1.9.1

Regards,
Helin