[PATCH RFC net-next] net: phylink: always config mac for (delayed) phy

[Eric Woudstra <ericwouds@gmail.com>]

The situation: mtk lynxi pcs (eth1 on BananaPi R3) with a rollball
rtl8221b sfp.

When setting eth1 link up, the phy is not immediately attached. It takes
a few seconds, pl->phydev is not set yet.

So when setting link eth1 up:

phylink_mac_config: mode=inband/2500base-x/none adv=00,00000000,00008000,
0000e240 pause=04

When the phy is attached the link an mode does not change and
phylink_mac_initial_config() is not called. No message 'Link is Up' found
in the kernel log.

We need:

phylink_mac_config: mode=phy/2500base-x/none adv=00,00000000,00008000,
000060ef pause=04

Perhaps forcing phylink_mac_initial_config() always for a phy is not the
desired approach, so I send this patch as RFC to see which approach
will be most suitable.

Log before this patch is applied:
[root@bpir3 ~]# dmesg | grep eth1
[    2.515179] mtk_soc_eth 15100000.ethernet eth1: mediatek frame engine at 0xffff800082380000, irq 123
[   38.271431] mtk_soc_eth 15100000.ethernet eth1: configuring for inband/2500base-x link mode
[   38.279828] mtk_soc_eth 15100000.ethernet eth1: major config, requested inband/2500base-x
[   38.288009] mtk_soc_eth 15100000.ethernet eth1: interface 2500base-x inband modes: pcs=01 phy=00
[   38.296800] mtk_soc_eth 15100000.ethernet eth1: major config, active inband/inband,an-disabled/2500base-x
[   38.306362] mtk_soc_eth 15100000.ethernet eth1: phylink_mac_config: mode=inband/2500base-x/none adv=00,00000000,00008000,0000e240 pause=04
[   39.220149] mtk_soc_eth 15100000.ethernet eth1:  interface 2 (mii) rate match none supports 0-3,6-7,13-14
[   39.229758] mtk_soc_eth 15100000.ethernet eth1:  interface 3 (gmii) rate match none supports 0-3,5-7,13-14
[   39.239420] mtk_soc_eth 15100000.ethernet eth1:  interface 4 (sgmii) rate match none supports 0-3,5-7,13-14
[   39.249173] mtk_soc_eth 15100000.ethernet eth1:  interface 22 (1000base-x) rate match none supports 5-7,13-14
[   39.259080] mtk_soc_eth 15100000.ethernet eth1:  interface 23 (2500base-x) rate match none supports 6-7,13-14,47
[   39.594676] mtk_soc_eth 15100000.ethernet eth1: PHY i2c:sfp-1:11 uses interfaces 4,23, validating 4,23
[   39.603992] mtk_soc_eth 15100000.ethernet eth1:  interface 4 (sgmii) rate match none supports 0-3,5-7,13-14
[   39.650080] mtk_soc_eth 15100000.ethernet eth1:  interface 23 (2500base-x) rate match none supports 6-7,13-14,47
[   39.660266] mtk_soc_eth 15100000.ethernet eth1: PHY [i2c:sfp-1:11] driver [RTL8221B-VB-CG 2.5Gbps PHY (C45)] (irq=POLL)
[   39.671037] mtk_soc_eth 15100000.ethernet eth1: phy: 2500base-x setting supported 00,00000000,00008000,000060ef advertising 00,00000000,00008000,000060ef
[   39.684761] mtk_soc_eth 15100000.ethernet eth1: requesting link mode inband/2500base-x with support 00,00000000,00008000,000060ef
[   40.380076] mtk_soc_eth 15100000.ethernet eth1: phy link down 2500base-x/Unknown/Unknown/none/off
[   40.397090] brlan: port 5(eth1) entered blocking state
[   40.402223] brlan: port 5(eth1) entered disabled state
[   40.407437] mtk_soc_eth 15100000.ethernet eth1: entered allmulticast mode
[   40.414400] mtk_soc_eth 15100000.ethernet eth1: entered promiscuous mode
[   44.500077] mtk_soc_eth 15100000.ethernet eth1: phy link up 2500base-x/2.5Gbps/Full/none/off
[   44.508528] mtk_soc_eth 15100000.ethernet eth1: No phy led trigger registered for speed(2500)

Log after this patch is applied:
[root@bpir3 ~]# dmesg | grep eth1
[    2.515149] mtk_soc_eth 15100000.ethernet eth1: mediatek frame engine at 0xffff800082400000, irq 123
[   38.989414] mtk_soc_eth 15100000.ethernet eth1: configuring for inband/2500base-x link mode
[   38.997838] mtk_soc_eth 15100000.ethernet eth1: major config, requested inband/2500base-x
[   39.006029] mtk_soc_eth 15100000.ethernet eth1: interface 2500base-x inband modes: pcs=01 phy=00
[   39.014818] mtk_soc_eth 15100000.ethernet eth1: major config, active inband/inband,an-disabled/2500base-x
[   39.024368] mtk_soc_eth 15100000.ethernet eth1: phylink_mac_config: mode=inband/2500base-x/none adv=00,00000000,00008000,0000e240 pause=04
[   39.960119] mtk_soc_eth 15100000.ethernet eth1:  interface 2 (mii) rate match none supports 0-3,6-7,13-14
[   39.969738] mtk_soc_eth 15100000.ethernet eth1:  interface 3 (gmii) rate match none supports 0-3,5-7,13-14
[   39.979409] mtk_soc_eth 15100000.ethernet eth1:  interface 4 (sgmii) rate match none supports 0-3,5-7,13-14
[   39.989153] mtk_soc_eth 15100000.ethernet eth1:  interface 22 (1000base-x) rate match none supports 5-7,13-14
[   39.999063] mtk_soc_eth 15100000.ethernet eth1:  interface 23 (2500base-x) rate match none supports 6-7,13-14,47
[   40.334663] mtk_soc_eth 15100000.ethernet eth1: PHY i2c:sfp-1:11 uses interfaces 4,23, validating 4,23
[   40.343980] mtk_soc_eth 15100000.ethernet eth1:  interface 4 (sgmii) rate match none supports 0-3,5-7,13-14
[   40.390049] mtk_soc_eth 15100000.ethernet eth1:  interface 23 (2500base-x) rate match none supports 6-7,13-14,47
[   40.400234] mtk_soc_eth 15100000.ethernet eth1: PHY [i2c:sfp-1:11] driver [RTL8221B-VB-CG 2.5Gbps PHY (C45)] (irq=POLL)
[   40.411005] mtk_soc_eth 15100000.ethernet eth1: phy: 2500base-x setting supported 00,00000000,00008000,000060ef advertising 00,00000000,00008000,000060ef
[   40.424730] mtk_soc_eth 15100000.ethernet eth1: requesting link mode inband/2500base-x with support 00,00000000,00008000,000060ef
[   40.436368] mtk_soc_eth 15100000.ethernet eth1: major config, requested inband/2500base-x
[   40.444539] mtk_soc_eth 15100000.ethernet eth1: interface 2500base-x inband modes: pcs=01 phy=00
[   40.453307] mtk_soc_eth 15100000.ethernet eth1: major config, active phy/outband/2500base-x
[   40.461653] mtk_soc_eth 15100000.ethernet eth1: phylink_mac_config: mode=phy/2500base-x/none adv=00,00000000,00008000,000060ef pause=04
[   41.170029] mtk_soc_eth 15100000.ethernet eth1: phy link down 2500base-x/Unknown/Unknown/none/off
[   41.187047] brlan: port 5(eth1) entered blocking state
[   41.192213] brlan: port 5(eth1) entered disabled state
[   41.197404] mtk_soc_eth 15100000.ethernet eth1: entered allmulticast mode
[   41.204358] mtk_soc_eth 15100000.ethernet eth1: entered promiscuous mode
[   46.600038] mtk_soc_eth 15100000.ethernet eth1: phy link up 2500base-x/2.5Gbps/Full/none/off
[   46.600057] mtk_soc_eth 15100000.ethernet eth1: Link is Up - 2.5Gbps/Full - flow control off
[   46.616926] mtk_soc_eth 15100000.ethernet eth1: No phy led trigger registered for speed(2500)
[   46.634003] brlan: port 5(eth1) entered blocking state
[   46.639155] brlan: port 5(eth1) entered forwarding state

Signed-off-by: Eric Woudstra <ericwouds@gmail.com>
---
 drivers/net/phy/phylink.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 6d50c2fdb190..6fd66ba9002a 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -3424,6 +3424,9 @@ static void phylink_sfp_set_config(struct phylink *pl,
 			     phy_modes(state->interface));
 	}
 
+	if (pl->phydev)
+		changed = true;
+
 	if (changed && !test_bit(PHYLINK_DISABLE_STOPPED,
 				 &pl->phylink_disable_state))
 		phylink_mac_initial_config(pl, false);
-- 
2.47.1