nfp: centralize the buffer size calculation

Add a helper function to calculate the buffer size at run time.
Buffer lengths will now depend on the FW prepend configuration
instead of assuming the most space consuming configuration and
defaulting to 2k buffers at initialization time.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2016-10-31 20:43:13 +00:00 committed by David S. Miller
parent fa95f1d2bf
commit bf187ea01b
2 changed files with 21 additions and 9 deletions

View file

@ -75,7 +75,6 @@
/* Default size for MTU and freelist buffer sizes */
#define NFP_NET_DEFAULT_MTU 1500
#define NFP_NET_DEFAULT_RX_BUFSZ 2048
/* Maximum number of bytes prepended to a packet */
#define NFP_NET_MAX_PREPEND 64

View file

@ -1030,6 +1030,19 @@ static void nfp_net_tx_timeout(struct net_device *netdev)
/* Receive processing
*/
static unsigned int
nfp_net_calc_fl_bufsz(struct nfp_net *nn, unsigned int mtu)
{
unsigned int fl_bufsz;
if (nn->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
fl_bufsz = NFP_NET_MAX_PREPEND;
else
fl_bufsz = nn->rx_offset;
fl_bufsz += ETH_HLEN + VLAN_HLEN * 2 + mtu;
return fl_bufsz;
}
/**
* nfp_net_rx_alloc_one() - Allocate and map skb for RX
@ -2191,7 +2204,7 @@ static int nfp_net_change_mtu(struct net_device *netdev, int new_mtu)
old_mtu = netdev->mtu;
old_fl_bufsz = nn->fl_bufsz;
new_fl_bufsz = NFP_NET_MAX_PREPEND + ETH_HLEN + VLAN_HLEN * 2 + new_mtu;
new_fl_bufsz = nfp_net_calc_fl_bufsz(nn, new_mtu);
if (!netif_running(netdev)) {
netdev->mtu = new_mtu;
@ -2731,12 +2744,18 @@ int nfp_net_netdev_init(struct net_device *netdev)
nfp_net_write_mac_addr(nn);
/* Determine RX packet/metadata boundary offset */
if (nn->fw_ver.major >= 2)
nn->rx_offset = nn_readl(nn, NFP_NET_CFG_RX_OFFSET);
else
nn->rx_offset = NFP_NET_RX_OFFSET;
/* Set default MTU and Freelist buffer size */
if (nn->max_mtu < NFP_NET_DEFAULT_MTU)
netdev->mtu = nn->max_mtu;
else
netdev->mtu = NFP_NET_DEFAULT_MTU;
nn->fl_bufsz = NFP_NET_DEFAULT_RX_BUFSZ;
nn->fl_bufsz = nfp_net_calc_fl_bufsz(nn, netdev->mtu);
/* Advertise/enable offloads based on capabilities
*
@ -2807,12 +2826,6 @@ int nfp_net_netdev_init(struct net_device *netdev)
nn->ctrl |= NFP_NET_CFG_CTRL_IRQMOD;
}
/* Determine RX packet/metadata boundary offset */
if (nn->fw_ver.major >= 2)
nn->rx_offset = nn_readl(nn, NFP_NET_CFG_RX_OFFSET);
else
nn->rx_offset = NFP_NET_RX_OFFSET;
/* Stash the re-configuration queue away. First odd queue in TX Bar */
nn->qcp_cfg = nn->tx_bar + NFP_QCP_QUEUE_ADDR_SZ;