From 2dd6acb795962638cf57dd5e1248dd30588ae7a7 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 29 Sep 2021 18:04:39 +0300 Subject: [PATCH] net: introduce a helper to determine whether to use in-band autoneg Certain serial SERDES protocols like 1000base-x, 2500base-x, SGMII, USXGMII can operate either in a mode where the PHY (be it on-board or inside an SFP module) passes the link parameters (speed, duplex, pause) to the MAC through in-band through control words standardized by IEEE 802.3 clause 37, or in a mode where the MAC must configure (force) its link parameters based on information obtained out-of-band (MDIO reads, guesswork etc). In Linux, the OF node property named "managed" is parsed by the phylink framework, and the convention is that if a driver uses phylink, then the presence of this property means that in-band autoneg should be enabled, otherwise it shouldn't. To be compatible with the OF node bindings of drivers that use phylink in Linux, introduce parsing support for this property in U-Boot too. Signed-off-by: Vladimir Oltean Reviewed-by: Ramon Fried Reviewed-by: Bin Meng Reviewed-by: Ramon Fried --- drivers/core/of_extra.c | 12 ++++++++++++ include/dm/of_extra.h | 14 ++++++++++++++ 2 files changed, 26 insertions(+) diff --git a/drivers/core/of_extra.c b/drivers/core/of_extra.c index 632a1c2210..59ce9174ad 100644 --- a/drivers/core/of_extra.c +++ b/drivers/core/of_extra.c @@ -155,3 +155,15 @@ bool ofnode_phy_is_fixed_link(ofnode eth_node, ofnode *phy_node) return true; } + +bool ofnode_eth_uses_inband_aneg(ofnode eth_node) +{ + bool inband_aneg = false; + const char *managed; + + managed = ofnode_read_string(eth_node, "managed"); + if (managed && !strcmp(managed, "in-band-status")) + inband_aneg = true; + + return inband_aneg; +} diff --git a/include/dm/of_extra.h b/include/dm/of_extra.h index f0d205491c..c2498aa585 100644 --- a/include/dm/of_extra.h +++ b/include/dm/of_extra.h @@ -114,4 +114,18 @@ int ofnode_decode_memory_region(ofnode config_node, const char *mem_type, */ bool ofnode_phy_is_fixed_link(ofnode eth_node, ofnode *phy_node); +/** + * ofnode_eth_uses_inband_aneg() - Detect whether MAC should use in-band autoneg + * + * This function detects whether the Ethernet controller should use IEEE 802.3 + * clause 37 in-band autonegotiation for serial protocols such as 1000base-x, + * SGMII, USXGMII, etc. The property is relevant when the Ethernet controller + * is connected to an on-board PHY or an SFP cage, and is not relevant when it + * has a fixed link (in that case, in-band autoneg should not be used). + * + * @param eth_node ofnode belonging to the Ethernet controller + * @return true if in-band autoneg should be used, false otherwise + */ +bool ofnode_eth_uses_inband_aneg(ofnode eth_node); + #endif