kernel: backport bgmac upstream commits from 5.15 / for 5.16

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
(cherry picked from commit fd71ef34b75c81646d17d21d80dc3a5b5e2e6bb8)

2 files changed, 138 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.4/710-v5.16-0001-net-bgmac-improve-handling-PHY.patch b/target/linux/generic/backport-5.4/710-v5.16-0001-net-bgmac-improve-handling-PHY.patch
new file mode 100644
index 0000000000..6788a2ec35
--- /dev/null
+++ b/target/linux/generic/backport-5.4/710-v5.16-0001-net-bgmac-improve-handling-PHY.patch
@@ -0,0 +1,84 @@
+From b5375509184dc23d2b7fa0c5ed8763899ccc9674 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Sat, 2 Oct 2021 19:58:11 +0200
+Subject: [PATCH] net: bgmac: improve handling PHY
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+1. Use info from DT if available
+
+It allows describing for example a fixed link. It's more accurate than
+just guessing there may be one (depending on a chipset).
+
+2. Verify PHY ID before trying to connect PHY
+
+PHY addr 0x1e (30) is special in Broadcom routers and means a switch
+connected as MDIO devices instead of a real PHY. Don't try connecting to
+it.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/broadcom/bgmac-bcma.c | 33 ++++++++++++++--------
+ 1 file changed, 21 insertions(+), 12 deletions(-)
+
+--- a/drivers/net/ethernet/broadcom/bgmac-bcma.c
++++ b/drivers/net/ethernet/broadcom/bgmac-bcma.c
+@@ -11,6 +11,7 @@
+ #include <linux/bcma/bcma.h>
+ #include <linux/brcmphy.h>
+ #include <linux/etherdevice.h>
++#include <linux/of_mdio.h>
+ #include <linux/of_net.h>
+ #include "bgmac.h"
+ 
+@@ -86,17 +87,28 @@ static int bcma_phy_connect(struct bgmac
+ 	struct phy_device *phy_dev;
+ 	char bus_id[MII_BUS_ID_SIZE + 3];
+ 
++	/* DT info should be the most accurate */
++	phy_dev = of_phy_get_and_connect(bgmac->net_dev, bgmac->dev->of_node,
++					 bgmac_adjust_link);
++	if (phy_dev)
++		return 0;
++
+ 	/* Connect to the PHY */
+-	snprintf(bus_id, sizeof(bus_id), PHY_ID_FMT, bgmac->mii_bus->id,
+-		 bgmac->phyaddr);
+-	phy_dev = phy_connect(bgmac->net_dev, bus_id, bgmac_adjust_link,
+-			      PHY_INTERFACE_MODE_MII);
+-	if (IS_ERR(phy_dev)) {
+-		dev_err(bgmac->dev, "PHY connection failed\n");
+-		return PTR_ERR(phy_dev);
++	if (bgmac->mii_bus && bgmac->phyaddr != BGMAC_PHY_NOREGS) {
++		snprintf(bus_id, sizeof(bus_id), PHY_ID_FMT, bgmac->mii_bus->id,
++			 bgmac->phyaddr);
++		phy_dev = phy_connect(bgmac->net_dev, bus_id, bgmac_adjust_link,
++				      PHY_INTERFACE_MODE_MII);
++		if (IS_ERR(phy_dev)) {
++			dev_err(bgmac->dev, "PHY connection failed\n");
++			return PTR_ERR(phy_dev);
++		}
++
++		return 0;
+ 	}
+ 
+-	return 0;
++	/* Assume a fixed link to the switch port */
++	return bgmac_phy_connect_direct(bgmac);
+ }
+ 
+ static const struct bcma_device_id bgmac_bcma_tbl[] = {
+@@ -297,10 +309,7 @@ static int bgmac_probe(struct bcma_devic
+ 	bgmac->cco_ctl_maskset = bcma_bgmac_cco_ctl_maskset;
+ 	bgmac->get_bus_clock = bcma_bgmac_get_bus_clock;
+ 	bgmac->cmn_maskset32 = bcma_bgmac_cmn_maskset32;
+-	if (bgmac->mii_bus)
+-		bgmac->phy_connect = bcma_phy_connect;
+-	else
+-		bgmac->phy_connect = bgmac_phy_connect_direct;
++	bgmac->phy_connect = bcma_phy_connect;
+ 
+ 	err = bgmac_enet_probe(bgmac);
+ 	if (err)
diff --git a/target/linux/generic/backport-5.4/710-v5.16-0002-net-bgmac-support-MDIO-described-in-DT.patch b/target/linux/generic/backport-5.4/710-v5.16-0002-net-bgmac-support-MDIO-described-in-DT.patch
new file mode 100644
index 0000000000..f134828273
--- /dev/null
+++ b/target/linux/generic/backport-5.4/710-v5.16-0002-net-bgmac-support-MDIO-described-in-DT.patch
@@ -0,0 +1,54 @@
+From 45c9d966688e7fad7f24bfc450547d91e4304d0b Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Sat, 2 Oct 2021 19:58:12 +0200
+Subject: [PATCH] net: bgmac: support MDIO described in DT
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Check ethernet controller DT node for "mdio" subnode and use it with
+of_mdiobus_register() when present. That allows specifying MDIO and its
+PHY devices in a standard DT based way.
+
+This is required for BCM53573 SoC support. That family is sometimes
+called Northstar (by marketing?) but is quite different from it. It uses
+different CPU(s) and many different hw blocks.
+
+One of shared blocks in BCM53573 is Ethernet controller. Switch however
+is not SRAB accessible (as it Northstar) but is MDIO attached.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+--- a/drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c
++++ b/drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c
+@@ -10,6 +10,7 @@
+ 
+ #include <linux/bcma/bcma.h>
+ #include <linux/brcmphy.h>
++#include <linux/of_mdio.h>
+ #include "bgmac.h"
+ 
+ static bool bcma_mdio_wait_value(struct bcma_device *core, u16 reg, u32 mask,
+@@ -211,6 +212,7 @@ struct mii_bus *bcma_mdio_mii_register(s
+ {
+ 	struct bcma_device *core = bgmac->bcma.core;
+ 	struct mii_bus *mii_bus;
++	struct device_node *np;
+ 	int err;
+ 
+ 	mii_bus = mdiobus_alloc();
+@@ -229,7 +231,9 @@ struct mii_bus *bcma_mdio_mii_register(s
+ 	mii_bus->parent = &core->dev;
+ 	mii_bus->phy_mask = ~(1 << bgmac->phyaddr);
+ 
+-	err = mdiobus_register(mii_bus);
++	np = of_get_child_by_name(core->dev.of_node, "mdio");
++
++	err = of_mdiobus_register(mii_bus, np);
+ 	if (err) {
+ 		dev_err(&core->dev, "Registration of mii bus failed\n");
+ 		goto err_free_bus;