openwrt/package/kernel/qca-ssdk/patches/103-mdio-adapt-to-C22-and-C45-read-write-split.patch

From bdae481e89cbe551068a99028bb57119b59f5ff4 Mon Sep 17 00:00:00 2001
From: Robert Marko <robimarko@gmail.com>
Date: Tue, 26 Mar 2024 12:19:49 +0100
Subject: [PATCH] mdio: adapt to C22 and C45 read/write split

Kernel 6.3 has introduced separate C45 read/write operations, and thus
split them out of the C22 operations completely so the old way of marking
C45 reads and writes via the register value does not work anymore.

This is causing SSDK to fail and find C45 only PHY-s such as Aquantia ones:
[   22.187877] ssdk_phy_driver_init[371]:INFO:dev_id = 0, phy_adress = 8, phy_id = 0x0 phytype doesn't match
[   22.209924] ssdk_phy_driver_init[371]:INFO:dev_id = 0, phy_adress = 0, phy_id = 0x0 phytype doesn't match

This in turn causes USXGMII MAC autoneg bit to not get set and then UNIPHY
autoneg will time out, causing the 10G ports not to work:
[   37.292784] uniphy autoneg time out!

So, lets detect C45 reads and writes by the magic BIT(30) in the register
argument and if so call separate C45 mdiobus read/write functions.

Signed-off-by: Robert Marko <robimarko@gmail.com>
---
 include/init/ssdk_plat.h |  7 +++++++
 src/init/ssdk_plat.c     | 30 ++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+)

--- a/include/init/ssdk_plat.h
+++ b/include/init/ssdk_plat.h
@@ -505,3 +505,10 @@ void ssdk_plat_exit(a_uint32_t dev_id);
 
 #endif
 /*qca808x_end*/
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0))
+#define MII_ADDR_C45		(1<<30)
+#define MII_DEVADDR_C45_SHIFT	16
+#define MII_DEVADDR_C45_MASK	GENMASK(20, 16)
+#define MII_REGADDR_C45_MASK	GENMASK(15, 0)
+#endif
--- a/src/init/ssdk_plat.c
+++ b/src/init/ssdk_plat.c
@@ -356,6 +356,18 @@ phy_addr_validation_check(a_uint32_t phy
 		return A_TRUE;
 }
 
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0))
+static inline u16 mdiobus_c45_regad(u32 regnum)
+{
+	return FIELD_GET(MII_REGADDR_C45_MASK, regnum);
+}
+
+static inline u16 mdiobus_c45_devad(u32 regnum)
+{
+	return FIELD_GET(MII_DEVADDR_C45_MASK, regnum);
+}
+#endif
+
 sw_error_t
 qca_ar8327_phy_read(a_uint32_t dev_id, a_uint32_t phy_addr,
                            a_uint32_t reg, a_uint16_t* data)
@@ -371,9 +383,18 @@ qca_ar8327_phy_read(a_uint32_t dev_id, a
 	if (!bus)
 		return SW_NOT_SUPPORTED;
 	phy_addr = TO_PHY_ADDR(phy_addr);
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0))
+	mutex_lock(&bus->mdio_lock);
+	if (reg & MII_ADDR_C45)
+		*data = __mdiobus_c45_read(bus, phy_addr, mdiobus_c45_devad(reg), mdiobus_c45_regad(reg));
+	else
+		*data = __mdiobus_read(bus, phy_addr, reg);
+	mutex_unlock(&bus->mdio_lock);
+#else
 	mutex_lock(&bus->mdio_lock);
 	*data = __mdiobus_read(bus, phy_addr, reg);
 	mutex_unlock(&bus->mdio_lock);
+#endif
 
 	return 0;
 }
@@ -393,9 +414,18 @@ qca_ar8327_phy_write(a_uint32_t dev_id,
 	if (!bus)
 		return SW_NOT_SUPPORTED;
 	phy_addr = TO_PHY_ADDR(phy_addr);
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0))
+	mutex_lock(&bus->mdio_lock);
+	if (reg & MII_ADDR_C45)
+		__mdiobus_c45_write(bus, phy_addr, mdiobus_c45_devad(reg), mdiobus_c45_regad(reg), data);
+	else
+		__mdiobus_write(bus, phy_addr, reg, data);
+	mutex_unlock(&bus->mdio_lock);
+#else
 	mutex_lock(&bus->mdio_lock);
 	__mdiobus_write(bus, phy_addr, reg, data);
 	mutex_unlock(&bus->mdio_lock);
+#endif
 
 	return 0;
 }