[dpdk-dev] [PATCH 2/6] net/tap: add speed capabilities

[Wiles, Keith]

> On Mar 3, 2017, at 3:46 AM, Pascal Mazon <pascal.mazon at 6wind.com> wrote:
> 
> Tap PMD is flexible, it supports any speed.
> 
> Signed-off-by: Pascal Mazon <pascal.mazon at 6wind.com>
> ---
> doc/guides/nics/features/tap.ini |  1 +
> drivers/net/tap/rte_eth_tap.c    | 35 +++++++++++++++++++++++++++++++++++
> 2 files changed, 36 insertions(+)
> 
> diff --git a/doc/guides/nics/features/tap.ini b/doc/guides/nics/features/tap.ini
> index d9b47a003654..dad5a0561087 100644
> --- a/doc/guides/nics/features/tap.ini
> +++ b/doc/guides/nics/features/tap.ini
> @@ -9,6 +9,7 @@ Jumbo frame          = Y
> Promiscuous mode     = Y
> Allmulticast mode    = Y
> Basic stats          = Y
> +Speed capabilities   = Y
> Unicast MAC filter   = Y
> Other kdrv           = Y
> ARMv7                = Y
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index 994c8be701c8..6670dfbb35ce 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -351,6 +351,40 @@ tap_dev_configure(struct rte_eth_dev *dev __rte_unused)
> 	return 0;
> }
> 
> +static uint32_t
> +tap_dev_speed_capa(void)
> +{
> +	uint32_t speed = pmd_link.link_speed;
> +	uint32_t capa = 0;
> +
> +	if (speed >= ETH_SPEED_NUM_10M)
> +		capa |= ETH_LINK_SPEED_10M;
> +	if (speed >= ETH_SPEED_NUM_100M)
> +		capa |= ETH_LINK_SPEED_100M;
> +	if (speed >= ETH_SPEED_NUM_1G)
> +		capa |= ETH_LINK_SPEED_1G;
> +	if (speed >= ETH_SPEED_NUM_5G)
> +		capa |= ETH_LINK_SPEED_2_5G;
> +	if (speed >= ETH_SPEED_NUM_5G)
> +		capa |= ETH_LINK_SPEED_5G;
> +	if (speed >= ETH_SPEED_NUM_10G)
> +		capa |= ETH_LINK_SPEED_10G;
> +	if (speed >= ETH_SPEED_NUM_20G)
> +		capa |= ETH_LINK_SPEED_20G;
> +	if (speed >= ETH_SPEED_NUM_25G)
> +		capa |= ETH_LINK_SPEED_25G;
> +	if (speed >= ETH_SPEED_NUM_40G)
> +		capa |= ETH_LINK_SPEED_40G;
> +	if (speed >= ETH_SPEED_NUM_50G)
> +		capa |= ETH_LINK_SPEED_50G;
> +	if (speed >= ETH_SPEED_NUM_56G)
> +		capa |= ETH_LINK_SPEED_56G;
> +	if (speed >= ETH_SPEED_NUM_100G)
> +		capa |= ETH_LINK_SPEED_100G;

In the real world the NIC may only support 50G an not say 10M, so in that case this code would be wrong as it would set all of the speeds up to 50G. I do not think the code should be changed, but I add a comment to tell the developer the issue here. I do not want someone copying the code and thinking is i correct for a real device.

> +
> +	return capa;
> +}
> +
> static void
> tap_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
> {
> @@ -363,6 +397,7 @@ tap_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
> 	dev_info->max_tx_queues = internals->nb_queues;
> 	dev_info->min_rx_bufsize = 0;
> 	dev_info->pci_dev = NULL;
> +	dev_info->speed_capa = tap_dev_speed_capa();
> }
> 
> static void
> -- 
> 2.8.0.rc0
> 

Regards,
Keith