[PATCH v2 2/2] net: phy: dp83826: support TX data voltage tuning
From: Catalin Popescu
Date: Wed Feb 07 2024 - 13:00:35 EST
DP83826 offers the possibility to tune the voltage of logical levels
of the MLT-3 encoded TX data. This is especially interesting when the
TX data path is lossy and we want to increase the voltage levels to
compensate the loss.
Signed-off-by: Catalin Popescu <catalin.popescu@xxxxxxxxxxxxxxxxxxxx>
---
Changes in v2:
- remove raw values mapping tables dp83826_cfg_dac_minus_raw/
dp83826_cfg_dac_plus_raw and replace them with functions
dp83826_to_dac_minus_one_regval/dp83826_to_dac_plus_one_regval
- increase readability of function dp83826_config_init
- change return value of function dp83826_of_init from int to void
since it never returns any error
---
drivers/net/phy/dp83822.c | 130 ++++++++++++++++++++++++++++++++++++--
1 file changed, 126 insertions(+), 4 deletions(-)
diff --git a/drivers/net/phy/dp83822.c b/drivers/net/phy/dp83822.c
index b7cb71817780..17070bb1a4b0 100644
--- a/drivers/net/phy/dp83822.c
+++ b/drivers/net/phy/dp83822.c
@@ -12,6 +12,7 @@
#include <linux/of.h>
#include <linux/phy.h>
#include <linux/netdevice.h>
+#include <linux/bitfield.h>
#define DP83822_PHY_ID 0x2000a240
#define DP83825S_PHY_ID 0x2000a140
@@ -34,6 +35,10 @@
#define MII_DP83822_GENCFG 0x465
#define MII_DP83822_SOR1 0x467
+/* DP83826 specific registers */
+#define MII_DP83826_VOD_CFG1 0x30b
+#define MII_DP83826_VOD_CFG2 0x30c
+
/* GENCFG */
#define DP83822_SIG_DET_LOW BIT(0)
@@ -110,6 +115,19 @@
#define DP83822_RX_ER_STR_MASK GENMASK(9, 8)
#define DP83822_RX_ER_SHIFT 8
+/* DP83826: VOD_CFG1 & VOD_CFG2 */
+#define DP83826_VOD_CFG1_MINUS_MDIX_MASK GENMASK(13, 12)
+#define DP83826_VOD_CFG1_MINUS_MDI_MASK GENMASK(11, 6)
+#define DP83826_VOD_CFG2_MINUS_MDIX_MASK GENMASK(15, 12)
+#define DP83826_VOD_CFG2_PLUS_MDIX_MASK GENMASK(11, 6)
+#define DP83826_VOD_CFG2_PLUS_MDI_MASK GENMASK(5, 0)
+#define DP83826_CFG_DAC_MINUS_MDIX_5_TO_4 GENMASK(5, 4)
+#define DP83826_CFG_DAC_MINUS_MDIX_3_TO_0 GENMASK(3, 0)
+#define DP83826_CFG_DAC_MPERCENT_PER_STEP 6250
+#define DP83826_CFG_DAC_MPERCENT_DEFAULT 100000
+#define DP83826_CFG_DAC_MINUS_DEFAULT 0x30
+#define DP83826_CFG_DAC_PLUS_DEFAULT 0x10
+
#define MII_DP83822_FIBER_ADVERTISE (ADVERTISED_TP | ADVERTISED_MII | \
ADVERTISED_FIBRE | \
ADVERTISED_Pause | ADVERTISED_Asym_Pause)
@@ -118,6 +136,8 @@ struct dp83822_private {
bool fx_signal_det_low;
int fx_enabled;
u16 fx_sd_enable;
+ u8 cfg_dac_minus;
+ u8 cfg_dac_plus;
};
static int dp83822_set_wol(struct phy_device *phydev,
@@ -233,7 +253,7 @@ static int dp83822_config_intr(struct phy_device *phydev)
DP83822_ENERGY_DET_INT_EN |
DP83822_LINK_QUAL_INT_EN);
- /* Private data pointer is NULL on DP83825/26 */
+ /* Private data pointer is NULL on DP83825 */
if (!dp83822 || !dp83822->fx_enabled)
misr_status |= DP83822_ANEG_COMPLETE_INT_EN |
DP83822_DUP_MODE_CHANGE_INT_EN |
@@ -254,7 +274,7 @@ static int dp83822_config_intr(struct phy_device *phydev)
DP83822_PAGE_RX_INT_EN |
DP83822_EEE_ERROR_CHANGE_INT_EN);
- /* Private data pointer is NULL on DP83825/26 */
+ /* Private data pointer is NULL on DP83825 */
if (!dp83822 || !dp83822->fx_enabled)
misr_status |= DP83822_ANEG_ERR_INT_EN |
DP83822_WOL_PKT_INT_EN;
@@ -474,6 +494,43 @@ static int dp83822_config_init(struct phy_device *phydev)
return dp8382x_disable_wol(phydev);
}
+static int dp83826_config_init(struct phy_device *phydev)
+{
+ struct dp83822_private *dp83822 = phydev->priv;
+ u16 val, mask;
+ int ret;
+
+ if (dp83822->cfg_dac_minus != DP83826_CFG_DAC_MINUS_DEFAULT) {
+ val = FIELD_PREP(DP83826_VOD_CFG1_MINUS_MDI_MASK, dp83822->cfg_dac_minus) |
+ FIELD_PREP(DP83826_VOD_CFG1_MINUS_MDIX_MASK,
+ FIELD_GET(DP83826_CFG_DAC_MINUS_MDIX_5_TO_4,
+ dp83822->cfg_dac_minus));
+ mask = DP83826_VOD_CFG1_MINUS_MDIX_MASK | DP83826_VOD_CFG1_MINUS_MDI_MASK;
+ ret = phy_modify_mmd(phydev, DP83822_DEVADDR, MII_DP83826_VOD_CFG1, mask, val);
+ if (ret)
+ return ret;
+
+ val = FIELD_PREP(DP83826_VOD_CFG2_MINUS_MDIX_MASK,
+ FIELD_GET(DP83826_CFG_DAC_MINUS_MDIX_3_TO_0,
+ dp83822->cfg_dac_minus));
+ mask = DP83826_VOD_CFG2_MINUS_MDIX_MASK;
+ ret = phy_modify_mmd(phydev, DP83822_DEVADDR, MII_DP83826_VOD_CFG2, mask, val);
+ if (ret)
+ return ret;
+ }
+
+ if (dp83822->cfg_dac_plus != DP83826_CFG_DAC_PLUS_DEFAULT) {
+ val = FIELD_PREP(DP83826_VOD_CFG2_PLUS_MDIX_MASK, dp83822->cfg_dac_plus) |
+ FIELD_PREP(DP83826_VOD_CFG2_PLUS_MDI_MASK, dp83822->cfg_dac_plus);
+ mask = DP83826_VOD_CFG2_PLUS_MDIX_MASK | DP83826_VOD_CFG2_PLUS_MDI_MASK;
+ ret = phy_modify_mmd(phydev, DP83822_DEVADDR, MII_DP83826_VOD_CFG2, mask, val);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
static int dp8382x_config_init(struct phy_device *phydev)
{
return dp8382x_disable_wol(phydev);
@@ -509,11 +566,44 @@ static int dp83822_of_init(struct phy_device *phydev)
return 0;
}
+
+static int dp83826_to_dac_minus_one_regval(int percent)
+{
+ int tmp = DP83826_CFG_DAC_MPERCENT_DEFAULT - percent;
+
+ return tmp / DP83826_CFG_DAC_MPERCENT_PER_STEP;
+}
+
+static int dp83826_to_dac_plus_one_regval(int percent)
+{
+ int tmp = percent - DP83826_CFG_DAC_MPERCENT_DEFAULT;
+
+ return tmp / DP83826_CFG_DAC_MPERCENT_PER_STEP;
+}
+
+static void dp83826_of_init(struct phy_device *phydev)
+{
+ struct dp83822_private *dp83822 = phydev->priv;
+ struct device *dev = &phydev->mdio.dev;
+ u32 val;
+
+ dp83822->cfg_dac_minus = DP83826_CFG_DAC_MINUS_DEFAULT;
+ if (!device_property_read_u32(dev, "ti,cfg-dac-minus-one-milli-percent", &val))
+ dp83822->cfg_dac_minus += dp83826_to_dac_minus_one_regval(val);
+
+ dp83822->cfg_dac_plus = DP83826_CFG_DAC_PLUS_DEFAULT;
+ if (!device_property_read_u32(dev, "ti,cfg-dac-plus-one-milli-percent", &val))
+ dp83822->cfg_dac_plus += dp83826_to_dac_plus_one_regval(val);
+}
#else
static int dp83822_of_init(struct phy_device *phydev)
{
return 0;
}
+
+static void dp83826_of_init(struct phy_device *phydev)
+{
+}
#endif /* CONFIG_OF_MDIO */
static int dp83822_read_straps(struct phy_device *phydev)
@@ -567,6 +657,22 @@ static int dp83822_probe(struct phy_device *phydev)
return 0;
}
+static int dp83826_probe(struct phy_device *phydev)
+{
+ struct dp83822_private *dp83822;
+
+ dp83822 = devm_kzalloc(&phydev->mdio.dev, sizeof(*dp83822),
+ GFP_KERNEL);
+ if (!dp83822)
+ return -ENOMEM;
+
+ phydev->priv = dp83822;
+
+ dp83826_of_init(phydev);
+
+ return 0;
+}
+
static int dp83822_suspend(struct phy_device *phydev)
{
int value;
@@ -610,6 +716,22 @@ static int dp83822_resume(struct phy_device *phydev)
.resume = dp83822_resume, \
}
+#define DP83826_PHY_DRIVER(_id, _name) \
+ { \
+ PHY_ID_MATCH_MODEL(_id), \
+ .name = (_name), \
+ /* PHY_BASIC_FEATURES */ \
+ .probe = dp83826_probe, \
+ .soft_reset = dp83822_phy_reset, \
+ .config_init = dp83826_config_init, \
+ .get_wol = dp83822_get_wol, \
+ .set_wol = dp83822_set_wol, \
+ .config_intr = dp83822_config_intr, \
+ .handle_interrupt = dp83822_handle_interrupt, \
+ .suspend = dp83822_suspend, \
+ .resume = dp83822_resume, \
+ }
+
#define DP8382X_PHY_DRIVER(_id, _name) \
{ \
PHY_ID_MATCH_MODEL(_id), \
@@ -628,8 +750,8 @@ static int dp83822_resume(struct phy_device *phydev)
static struct phy_driver dp83822_driver[] = {
DP83822_PHY_DRIVER(DP83822_PHY_ID, "TI DP83822"),
DP8382X_PHY_DRIVER(DP83825I_PHY_ID, "TI DP83825I"),
- DP8382X_PHY_DRIVER(DP83826C_PHY_ID, "TI DP83826C"),
- DP8382X_PHY_DRIVER(DP83826NC_PHY_ID, "TI DP83826NC"),
+ DP83826_PHY_DRIVER(DP83826C_PHY_ID, "TI DP83826C"),
+ DP83826_PHY_DRIVER(DP83826NC_PHY_ID, "TI DP83826NC"),
DP8382X_PHY_DRIVER(DP83825S_PHY_ID, "TI DP83825S"),
DP8382X_PHY_DRIVER(DP83825CM_PHY_ID, "TI DP83825M"),
DP8382X_PHY_DRIVER(DP83825CS_PHY_ID, "TI DP83825CS"),
--
2.34.1