4.19-stable review patch. If anyone has any objections, please let me know.
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From: Ryan C Goodfellow rgoodfel@isi.edu
[ Upstream commit 5948185b97fa1f83d7855e638a72982a1073ebf5 ]
This commit makes it possible to use devlink to split the 100G CXP Netronome into two 40G interfaces. Currently when you ask for 2 interfaces, the math in src/nfp_devlink.c:nfp_devlink_port_split calculates that you want 5 lanes per port because for some reason eth_port.port_lanes=10 (shouldn't this be 12 for CXP?). What we really want when asking for 2 breakout interfaces is 4 lanes per port. This commit makes that happen by calculating based on 8 lanes if 10 are present.
Signed-off-by: Ryan C Goodfellow rgoodfel@isi.edu Reviewed-by: Jakub Kicinski jakub.kicinski@netronome.com Reviewed-by: Greg Weeks greg.weeks@netronome.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/netronome/nfp/nfp_devlink.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-)
--- a/drivers/net/ethernet/netronome/nfp/nfp_devlink.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_devlink.c @@ -96,6 +96,7 @@ nfp_devlink_port_split(struct devlink *d { struct nfp_pf *pf = devlink_priv(devlink); struct nfp_eth_table_port eth_port; + unsigned int lanes; int ret;
if (count < 2) @@ -114,8 +115,12 @@ nfp_devlink_port_split(struct devlink *d goto out; }
- ret = nfp_devlink_set_lanes(pf, eth_port.index, - eth_port.port_lanes / count); + /* Special case the 100G CXP -> 2x40G split */ + lanes = eth_port.port_lanes / count; + if (eth_port.lanes == 10 && count == 2) + lanes = 8 / count; + + ret = nfp_devlink_set_lanes(pf, eth_port.index, lanes); out: mutex_unlock(&pf->lock);
@@ -128,6 +133,7 @@ nfp_devlink_port_unsplit(struct devlink { struct nfp_pf *pf = devlink_priv(devlink); struct nfp_eth_table_port eth_port; + unsigned int lanes; int ret;
mutex_lock(&pf->lock); @@ -143,7 +149,12 @@ nfp_devlink_port_unsplit(struct devlink goto out; }
- ret = nfp_devlink_set_lanes(pf, eth_port.index, eth_port.port_lanes); + /* Special case the 100G CXP -> 2x40G unsplit */ + lanes = eth_port.port_lanes; + if (eth_port.port_lanes == 8) + lanes = 10; + + ret = nfp_devlink_set_lanes(pf, eth_port.index, lanes); out: mutex_unlock(&pf->lock);