net: phy: micrel: Configure KSZ9021/KSZ9031 skew from OF

Add code to process the KSZ9021/KSZ9031 OF props if they are present
and configure skew registers based on the information from the OF.
This code is only enabled if the DM support for ethernet is also
enabled.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Chin Liang See <clsee@altera.com>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>

V2: - Implement struct ksz90x1_reg_field to describe the skew register
      fields more accurately.
    - Fix RXDV/TXEN skew register default value and offset.

1 files changed, 145 insertions, 1 deletions

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 5e49666bbb..19b6bc7472 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -9,9 +9,14 @@
  */
 #include <config.h>
 #include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
 #include <micrel.h>
 #include <phy.h>
 
+DECLARE_GLOBAL_DATA_PTR;
+
 static struct phy_driver KSZ804_driver = {
 	.name = "Micrel KSZ804",
 	.uid = 0x221510,
@@ -174,6 +179,73 @@ static int ksz90xx_startup(struct phy_device *phydev)
 	return 0;
 }
 
+/* Common OF config bits for KSZ9021 and KSZ9031 */
+#if defined(CONFIG_PHY_MICREL_KSZ9021) || defined(CONFIG_PHY_MICREL_KSZ9031)
+#ifdef CONFIG_DM_ETH
+struct ksz90x1_reg_field {
+	const char	*name;
+	const u8	size;	/* Size of the bitfield, in bits */
+	const u8	off;	/* Offset from bit 0 */
+	const u8	dflt;	/* Default value */
+};
+
+struct ksz90x1_ofcfg {
+	const u16			reg;
+	const u16			devad;
+	const struct ksz90x1_reg_field	*grp;
+	const u16			grpsz;
+};
+
+static const struct ksz90x1_reg_field ksz90x1_rxd_grp[] = {
+	{ "rxd0-skew-ps", 4, 0, 0x7 }, { "rxd1-skew-ps", 4, 4, 0x7 },
+	{ "rxd2-skew-ps", 4, 8, 0x7 }, { "rxd3-skew-ps", 4, 12, 0x7 }
+};
+
+static const struct ksz90x1_reg_field ksz90x1_txd_grp[] = {
+	{ "txd0-skew-ps", 4, 0, 0x7 }, { "txd1-skew-ps", 4, 4, 0x7 },
+	{ "txd2-skew-ps", 4, 8, 0x7 }, { "txd3-skew-ps", 4, 12, 0x7 },
+};
+
+static int ksz90x1_of_config_group(struct phy_device *phydev,
+				   struct ksz90x1_ofcfg *ofcfg)
+{
+	struct udevice *dev = phydev->dev;
+	struct phy_driver *drv = phydev->drv;
+	const int ps_to_regval = 200;
+	int val[4];
+	int i, changed = 0, offset, max;
+	u16 regval = 0;
+
+	if (!drv || !drv->writeext)
+		return -EOPNOTSUPP;
+
+	for (i = 0; i < ofcfg->grpsz; i++) {
+		val[i] = fdtdec_get_uint(gd->fdt_blob, dev->of_offset,
+					 ofcfg->grp[i].name, -1);
+		offset = ofcfg->grp[i].off;
+		if (val[i] == -1) {
+			/* Default register value for KSZ9021 */
+			regval |= ofcfg->grp[i].dflt << offset;
+		} else {
+			changed = 1;	/* Value was changed in OF */
+			/* Calculate the register value and fix corner cases */
+			if (val[i] > ps_to_regval * 0xf) {
+				max = (1 << ofcfg->grp[i].size) - 1;
+				regval |= max << offset;
+			} else {
+				regval |= (val[i] / ps_to_regval) << offset;
+			}
+		}
+	}
+
+	if (!changed)
+		return 0;
+
+	return drv->writeext(phydev, 0, ofcfg->devad, ofcfg->reg, regval);
+}
+#endif
+#endif
+
 #ifdef CONFIG_PHY_MICREL_KSZ9021
 /*
  * KSZ9021
@@ -188,6 +260,35 @@ static int ksz90xx_startup(struct phy_device *phydev)
 #define CTRL1000_CONFIG_MASTER		(1 << 11)
 #define CTRL1000_MANUAL_CONFIG		(1 << 12)
 
+#ifdef CONFIG_DM_ETH
+static const struct ksz90x1_reg_field ksz9021_clk_grp[] = {
+	{ "txen-skew-ps", 4, 0, 0x7 }, { "txc-skew-ps", 4, 4, 0x7 },
+	{ "rxdv-skew-ps", 4, 8, 0x7 }, { "rxc-skew-ps", 4, 12, 0x7 },
+};
+
+static int ksz9021_of_config(struct phy_device *phydev)
+{
+	struct ksz90x1_ofcfg ofcfg[] = {
+		{ MII_KSZ9021_EXT_RGMII_RX_DATA_SKEW, 0, ksz90x1_rxd_grp, 4 },
+		{ MII_KSZ9021_EXT_RGMII_TX_DATA_SKEW, 0, ksz90x1_txd_grp, 4 },
+		{ MII_KSZ9021_EXT_RGMII_CLOCK_SKEW, 0, ksz9021_clk_grp, 4 },
+	};
+	int i, ret = 0;
+
+	for (i = 0; i < ARRAY_SIZE(ofcfg); i++)
+		ret = ksz90x1_of_config_group(phydev, &(ofcfg[i]));
+		if (ret)
+			return ret;
+
+	return 0;
+}
+#else
+static int ksz9021_of_config(struct phy_device *phydev)
+{
+	return 0;
+}
+#endif
+
 int ksz9021_phy_extended_write(struct phy_device *phydev, int regnum, u16 val)
 {
 	/* extended registers */
@@ -224,6 +325,11 @@ static int ksz9021_config(struct phy_device *phydev)
 	const unsigned master = CTRL1000_PREFER_MASTER |
 			CTRL1000_CONFIG_MASTER | CTRL1000_MANUAL_CONFIG;
 	unsigned features = phydev->drv->features;
+	int ret;
+
+	ret = ksz9021_of_config(phydev);
+	if (ret)
+		return ret;
 
 	if (getenv("disable_giga"))
 		features &= ~(SUPPORTED_1000baseT_Half |
@@ -260,6 +366,36 @@ static struct phy_driver ksz9021_driver = {
 #define MII_KSZ9031_MMD_ACCES_CTRL	0x0d
 #define MII_KSZ9031_MMD_REG_DATA	0x0e
 
+#ifdef CONFIG_DM_ETH
+static const struct ksz90x1_reg_field ksz9031_ctl_grp[] =
+	{ { "txen-skew-ps", 4, 0, 0x7 }, { "rxdv-skew-ps", 4, 4, 0x7 } };
+static const struct ksz90x1_reg_field ksz9031_clk_grp[] =
+	{ { "rxc-skew-ps", 5, 0, 0xf }, { "txc-skew-ps", 5, 5, 0xf } };
+
+static int ksz9031_of_config(struct phy_device *phydev)
+{
+	struct ksz90x1_ofcfg ofcfg[] = {
+		{ MII_KSZ9031_EXT_RGMII_CTRL_SIG_SKEW, 2, ksz9031_ctl_grp, 2 },
+		{ MII_KSZ9031_EXT_RGMII_RX_DATA_SKEW, 2, ksz90x1_rxd_grp, 4 },
+		{ MII_KSZ9031_EXT_RGMII_TX_DATA_SKEW, 2, ksz90x1_txd_grp, 4 },
+		{ MII_KSZ9031_EXT_RGMII_CLOCK_SKEW, 2, ksz9031_clk_grp, 2 },
+	};
+	int i, ret = 0;
+
+	for (i = 0; i < ARRAY_SIZE(ofcfg); i++)
+		ret = ksz90x1_of_config_group(phydev, &(ofcfg[i]));
+		if (ret)
+			return ret;
+
+	return 0;
+}
+#else
+static int ksz9031_of_config(struct phy_device *phydev)
+{
+	return 0;
+}
+#endif
+
 /* Accessors to extended registers*/
 int ksz9031_phy_extended_write(struct phy_device *phydev,
 			       int devaddr, int regnum, u16 mode, u16 val)
@@ -304,13 +440,21 @@ static int ksz9031_phy_extwrite(struct phy_device *phydev, int addr,
 					 MII_KSZ9031_MOD_DATA_POST_INC_RW, val);
 };
 
+static int ksz9031_config(struct phy_device *phydev)
+{
+	int ret;
+	ret = ksz9031_of_config(phydev);
+	if (ret)
+		return ret;
+	return genphy_config(phydev);
+}
 
 static struct phy_driver ksz9031_driver = {
 	.name = "Micrel ksz9031",
 	.uid  = 0x221620,
 	.mask = 0xfffff0,
 	.features = PHY_GBIT_FEATURES,
-	.config   = &genphy_config,
+	.config   = &ksz9031_config,
 	.startup  = &ksz90xx_startup,
 	.shutdown = &genphy_shutdown,
 	.writeext = &ksz9031_phy_extwrite,