4.19-stable review patch. If anyone has any objections, please let me know.
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From: Yonglong Liu liuyonglong@huawei.com
[ Upstream commit f708aba40f9c1eeb9c7e93ed4863b5f85b09b288 ]
If a xge port just connect with an optical module and no fiber, it may have a fake link up because there may be interference on the hardware. This patch adds an anti-shake to avoid the problem. And the time of anti-shake is base on tests.
Fixes: b917078c1c10 ("net: hns: Add ACPI support to check SFP present") Signed-off-by: Yonglong Liu liuyonglong@huawei.com Signed-off-by: Jijie Shao shaojijie@huawei.com Reviewed-by: Wojciech Drewek wojciech.drewek@intel.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/hisilicon/hns/hns_dsaf_mac.c | 29 +++++++++++++++++++ 1 file changed, 29 insertions(+)
diff --git a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c index cfdc92de9dc0e..d2791bcff5d49 100644 --- a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c @@ -70,6 +70,27 @@ static enum mac_mode hns_get_enet_interface(const struct hns_mac_cb *mac_cb) } }
+static u32 hns_mac_link_anti_shake(struct mac_driver *mac_ctrl_drv) +{ +#define HNS_MAC_LINK_WAIT_TIME 5 +#define HNS_MAC_LINK_WAIT_CNT 40 + + u32 link_status = 0; + int i; + + if (!mac_ctrl_drv->get_link_status) + return link_status; + + for (i = 0; i < HNS_MAC_LINK_WAIT_CNT; i++) { + msleep(HNS_MAC_LINK_WAIT_TIME); + mac_ctrl_drv->get_link_status(mac_ctrl_drv, &link_status); + if (!link_status) + break; + } + + return link_status; +} + void hns_mac_get_link_status(struct hns_mac_cb *mac_cb, u32 *link_status) { struct mac_driver *mac_ctrl_drv; @@ -87,6 +108,14 @@ void hns_mac_get_link_status(struct hns_mac_cb *mac_cb, u32 *link_status) &sfp_prsnt); if (!ret) *link_status = *link_status && sfp_prsnt; + + /* for FIBER port, it may have a fake link up. + * when the link status changes from down to up, we need to do + * anti-shake. the anti-shake time is base on tests. + * only FIBER port need to do this. + */ + if (*link_status && !mac_cb->link) + *link_status = hns_mac_link_anti_shake(mac_ctrl_drv); }
mac_cb->link = *link_status;