net: phy: marvell: Support reg config via "marvell, reg-init" DT property

This patch adds support for the "marvell,reg-init" DT property, which
is used to describe board specific Marvell PHY register configurations
in the board dts file. This DT property is supported in the Linux Kernel
since a longer time. Adding it to U-Boot now, enables the boards which
describe the register settings in their DT files here as well.

I've included calling this marvell_of_reg_init() to all foo_config()
functions in this patch as well. If CONFIG_DM_ETH is not set, there is
no ofnode, or no "marvell,reg-init" property, the PHY initialization is
unchanged.

The function marvell_of_reg_init() is a port of the Linux version.
Please note that I explicitly did not add error checking and handling
to the U-Boot version, as this is basically not done for phy_read/write
in this Marvell PHY code.

This will be used by the upcoming ethernet support on the MIPS
Octeon EBB 7304 board.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Ramon Fried <rfried.dev@gmail.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Aaron Williams <awilliams@marvell.com>
Cc: Chandrakala Chavva <cchavva@marvell.com>
Cc: Marek BehĂșn <marek.behun@nic.cz>
Reviewed-by: Marek BehĂșn <marek.behun@nic.cz>
diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index a62c695..1dcb79d 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -104,6 +104,88 @@
 #define MIIM_88E151x_MODE_SGMII		1
 #define MIIM_88E151x_RESET_OFFS		15
 
+#if IS_ENABLED(CONFIG_DM_ETH)
+static int marvell_read_page(struct phy_device *phydev)
+{
+	return phy_read(phydev, MDIO_DEVAD_NONE, MII_MARVELL_PHY_PAGE);
+}
+
+static int marvell_write_page(struct phy_device *phydev, int page)
+{
+	return phy_write(phydev, MDIO_DEVAD_NONE, MII_MARVELL_PHY_PAGE, page);
+}
+
+/* Set and/or override some configuration registers based on the
+ * marvell,reg-init property stored in the of_node for the phydev.
+ *
+ * marvell,reg-init = <reg-page reg mask value>,...;
+ *
+ * There may be one or more sets of <reg-page reg mask value>:
+ *
+ * reg-page: which register bank to use.
+ * reg: the register.
+ * mask: if non-zero, ANDed with existing register value.
+ * value: ORed with the masked value and written to the regiser.
+ *
+ */
+static int marvell_of_reg_init(struct phy_device *phydev)
+{
+	const __be32 *prop;
+	int len, i, saved_page, current_page, ret = 0;
+
+	if (!ofnode_valid(phydev->node))
+		return 0;
+
+	prop = ofnode_get_property(phydev->node, "marvell,reg-init", &len);
+	if (!prop)
+		return 0;
+
+	saved_page = marvell_read_page(phydev);
+	if (saved_page < 0)
+		goto err;
+	current_page = saved_page;
+
+	len /= sizeof(*prop);
+	for (i = 0; i < len - 3; i += 4) {
+		u16 page = be32_to_cpup(prop + i);
+		u16 reg = be32_to_cpup(prop + i + 1);
+		u16 mask = be32_to_cpup(prop + i + 2);
+		u16 val_bits = be32_to_cpup(prop + i + 3);
+		int val;
+
+		if (page != current_page) {
+			current_page = page;
+			ret = marvell_write_page(phydev, page);
+			if (ret < 0)
+				goto err;
+		}
+
+		val = 0;
+		if (mask) {
+			val = phy_read(phydev, MDIO_DEVAD_NONE, reg);
+			if (val < 0) {
+				ret = val;
+				goto err;
+			}
+			val &= mask;
+		}
+		val |= val_bits;
+
+		ret = phy_write(phydev, MDIO_DEVAD_NONE, reg, val);
+		if (ret < 0)
+			goto err;
+	}
+
+err:
+	return marvell_write_page(phydev, saved_page);
+}
+#else
+static int marvell_of_reg_init(struct phy_device *phydev)
+{
+	return 0;
+}
+#endif /* CONFIG_DM_ETH */
+
 static int m88e1xxx_phy_extread(struct phy_device *phydev, int addr,
 				int devaddr, int regnum)
 {
@@ -143,6 +225,8 @@
 
 	phy_write(phydev, MDIO_DEVAD_NONE, MII_BMCR, BMCR_RESET);
 
+	marvell_of_reg_init(phydev);
+
 	genphy_config_aneg(phydev);
 
 	return 0;
@@ -298,6 +382,8 @@
 	/* soft reset */
 	phy_reset(phydev);
 
+	marvell_of_reg_init(phydev);
+
 	genphy_config_aneg(phydev);
 	genphy_restart_aneg(phydev);
 
@@ -397,6 +483,8 @@
 	/* soft reset */
 	phy_reset(phydev);
 
+	marvell_of_reg_init(phydev);
+
 	genphy_config_aneg(phydev);
 	genphy_restart_aneg(phydev);
 
@@ -417,6 +505,8 @@
 	/* Change Page Number */
 	phy_write(phydev, MDIO_DEVAD_NONE, MIIM_88E1118_PHY_PAGE, 0x0000);
 
+	marvell_of_reg_init(phydev);
+
 	return genphy_config_aneg(phydev);
 }
 
@@ -439,6 +529,8 @@
 {
 	int pg;
 
+	marvell_of_reg_init(phydev);
+
 	/* Configure the PHY */
 	genphy_config_aneg(phydev);
 
@@ -479,6 +571,8 @@
 			MIIM_M88E1145_RGMII_TX_DELAY;
 	phy_write(phydev, MDIO_DEVAD_NONE, MIIM_88E1145_PHY_EXT_CR, reg);
 
+	marvell_of_reg_init(phydev);
+
 	genphy_config_aneg(phydev);
 
 	/* soft reset */
@@ -511,6 +605,8 @@
 	phy_write(phydev, MDIO_DEVAD_NONE, 0x1e, 0x0);
 	phy_write(phydev, MDIO_DEVAD_NONE, 0x1e, 0x100);
 
+	marvell_of_reg_init(phydev);
+
 	genphy_config_aneg(phydev);
 
 	phy_reset(phydev);
@@ -544,6 +640,8 @@
 	/* Ensure to return to page 0 */
 	phy_write(phydev, MDIO_DEVAD_NONE, MIIM_88E1310_PHY_PAGE, 0x0000);
 
+	marvell_of_reg_init(phydev);
+
 	return genphy_config_aneg(phydev);
 }
 
@@ -578,6 +676,8 @@
 	phy_write(phydev, MDIO_DEVAD_NONE, MIIM_88E1118_PHY_PAGE, 0x0000);
 	phy_write(phydev, MDIO_DEVAD_NONE,  0, 0x9140);
 
+	marvell_of_reg_init(phydev);
+
 	res = genphy_config_aneg(phydev);
 	if (res < 0)
 		return res;