[PATCH v4 06/14] net: phy: adin: make RGMII internal delays configurable

From: Alexandru Ardelean
Date: Mon Aug 12 2019 - 07:24:31 EST


The internal delays for the RGMII are configurable for both RX & TX. This
change adds support for configuring them via device-tree (or ACPI).

Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---
drivers/net/phy/adin.c | 82 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 82 insertions(+)

diff --git a/drivers/net/phy/adin.c b/drivers/net/phy/adin.c
index badca6881c6c..c882fcd9ada5 100644
--- a/drivers/net/phy/adin.c
+++ b/drivers/net/phy/adin.c
@@ -5,11 +5,13 @@
* Copyright 2019 Analog Devices Inc.
*/
#include <linux/kernel.h>
+#include <linux/bitfield.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/phy.h>
+#include <linux/property.h>

#define PHY_ID_ADIN1200 0x0283bc20
#define PHY_ID_ADIN1300 0x0283bc30
@@ -32,15 +34,83 @@
#define ADIN1300_INT_STATUS_REG 0x0019

#define ADIN1300_GE_RGMII_CFG_REG 0xff23
+#define ADIN1300_GE_RGMII_RX_MSK GENMASK(8, 6)
+#define ADIN1300_GE_RGMII_RX_SEL(x) \
+ FIELD_PREP(ADIN1300_GE_RGMII_RX_MSK, x)
+#define ADIN1300_GE_RGMII_GTX_MSK GENMASK(5, 3)
+#define ADIN1300_GE_RGMII_GTX_SEL(x) \
+ FIELD_PREP(ADIN1300_GE_RGMII_GTX_MSK, x)
#define ADIN1300_GE_RGMII_RXID_EN BIT(2)
#define ADIN1300_GE_RGMII_TXID_EN BIT(1)
#define ADIN1300_GE_RGMII_EN BIT(0)

+/* RGMII internal delay settings for rx and tx for ADIN1300 */
+#define ADIN1300_RGMII_1_60_NS 0x0001
+#define ADIN1300_RGMII_1_80_NS 0x0002
+#define ADIN1300_RGMII_2_00_NS 0x0000
+#define ADIN1300_RGMII_2_20_NS 0x0006
+#define ADIN1300_RGMII_2_40_NS 0x0007
+
#define ADIN1300_GE_RMII_CFG_REG 0xff24
#define ADIN1300_GE_RMII_EN BIT(0)

+/**
+ * struct adin_cfg_reg_map - map a config value to aregister value
+ * @cfg value in device configuration
+ * @reg value in the register
+ */
+struct adin_cfg_reg_map {
+ int cfg;
+ int reg;
+};
+
+static const struct adin_cfg_reg_map adin_rgmii_delays[] = {
+ { 1600, ADIN1300_RGMII_1_60_NS },
+ { 1800, ADIN1300_RGMII_1_80_NS },
+ { 2000, ADIN1300_RGMII_2_00_NS },
+ { 2200, ADIN1300_RGMII_2_20_NS },
+ { 2400, ADIN1300_RGMII_2_40_NS },
+ { },
+};
+
+static int adin_lookup_reg_value(const struct adin_cfg_reg_map *tbl, int cfg)
+{
+ size_t i;
+
+ for (i = 0; tbl[i].cfg; i++) {
+ if (tbl[i].cfg == cfg)
+ return tbl[i].reg;
+ }
+
+ return -EINVAL;
+}
+
+static u32 adin_get_reg_value(struct phy_device *phydev,
+ const char *prop_name,
+ const struct adin_cfg_reg_map *tbl,
+ u32 dflt)
+{
+ struct device *dev = &phydev->mdio.dev;
+ u32 val;
+ int rc;
+
+ if (device_property_read_u32(dev, prop_name, &val))
+ return dflt;
+
+ rc = adin_lookup_reg_value(tbl, val);
+ if (rc < 0) {
+ phydev_warn(phydev,
+ "Unsupported value %u for %s using default (%u)\n",
+ val, prop_name, dflt);
+ return dflt;
+ }
+
+ return rc;
+}
+
static int adin_config_rgmii_mode(struct phy_device *phydev)
{
+ u32 val;
int reg;

if (!phy_interface_is_rgmii(phydev))
@@ -57,6 +127,12 @@ static int adin_config_rgmii_mode(struct phy_device *phydev)
if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) {
reg |= ADIN1300_GE_RGMII_RXID_EN;
+
+ val = adin_get_reg_value(phydev, "adi,rx-internal-delay-ps",
+ adin_rgmii_delays,
+ ADIN1300_RGMII_2_00_NS);
+ reg &= ~ADIN1300_GE_RGMII_RX_MSK;
+ reg |= ADIN1300_GE_RGMII_RX_SEL(val);
} else {
reg &= ~ADIN1300_GE_RGMII_RXID_EN;
}
@@ -64,6 +140,12 @@ static int adin_config_rgmii_mode(struct phy_device *phydev)
if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) {
reg |= ADIN1300_GE_RGMII_TXID_EN;
+
+ val = adin_get_reg_value(phydev, "adi,tx-internal-delay-ps",
+ adin_rgmii_delays,
+ ADIN1300_RGMII_2_00_NS);
+ reg &= ~ADIN1300_GE_RGMII_GTX_MSK;
+ reg |= ADIN1300_GE_RGMII_GTX_SEL(val);
} else {
reg &= ~ADIN1300_GE_RGMII_TXID_EN;
}
--
2.20.1