[PATCH 4.16 007/279] lan78xx: PHY DSP registers initialization to address EEE link drop issues with long cables

From: Greg Kroah-Hartman
Date: Mon Jun 18 2018 - 04:15:50 EST


4.16-stable review patch. If anyone has any objections, please let me know.

------------------

From: Raghuram Chary J <raghuramchary.jallipalli@xxxxxxxxxxxxx>

[ Upstream commit 1c2734b31d72316e3faaad88c0c9c46fa92a4b20 ]

The patch is to configure DSP registers of PHY device
to handle Gbe-EEE failures with >40m cable length.

Fixes: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
Signed-off-by: Raghuram Chary J <raghuramchary.jallipalli@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/phy/microchip.c | 178 ++++++++++++++++++++++++++++++++++++++++++-
include/linux/microchipphy.h | 8 +
2 files changed, 185 insertions(+), 1 deletion(-)

--- a/drivers/net/phy/microchip.c
+++ b/drivers/net/phy/microchip.c
@@ -20,6 +20,7 @@
#include <linux/ethtool.h>
#include <linux/phy.h>
#include <linux/microchipphy.h>
+#include <linux/delay.h>

#define DRIVER_AUTHOR "WOOJUNG HUH <woojung.huh@xxxxxxxxxxxxx>"
#define DRIVER_DESC "Microchip LAN88XX PHY driver"
@@ -30,6 +31,16 @@ struct lan88xx_priv {
__u32 wolopts;
};

+static int lan88xx_read_page(struct phy_device *phydev)
+{
+ return __phy_read(phydev, LAN88XX_EXT_PAGE_ACCESS);
+}
+
+static int lan88xx_write_page(struct phy_device *phydev, int page)
+{
+ return __phy_write(phydev, LAN88XX_EXT_PAGE_ACCESS, page);
+}
+
static int lan88xx_phy_config_intr(struct phy_device *phydev)
{
int rc;
@@ -66,6 +77,150 @@ static int lan88xx_suspend(struct phy_de
return 0;
}

+static int lan88xx_TR_reg_set(struct phy_device *phydev, u16 regaddr,
+ u32 data)
+{
+ int val, save_page, ret = 0;
+ u16 buf;
+
+ /* Save current page */
+ save_page = phy_save_page(phydev);
+ if (save_page < 0) {
+ pr_warn("Failed to get current page\n");
+ goto err;
+ }
+
+ /* Switch to TR page */
+ lan88xx_write_page(phydev, LAN88XX_EXT_PAGE_ACCESS_TR);
+
+ ret = __phy_write(phydev, LAN88XX_EXT_PAGE_TR_LOW_DATA,
+ (data & 0xFFFF));
+ if (ret < 0) {
+ pr_warn("Failed to write TR low data\n");
+ goto err;
+ }
+
+ ret = __phy_write(phydev, LAN88XX_EXT_PAGE_TR_HIGH_DATA,
+ (data & 0x00FF0000) >> 16);
+ if (ret < 0) {
+ pr_warn("Failed to write TR high data\n");
+ goto err;
+ }
+
+ /* Config control bits [15:13] of register */
+ buf = (regaddr & ~(0x3 << 13));/* Clr [14:13] to write data in reg */
+ buf |= 0x8000; /* Set [15] to Packet transmit */
+
+ ret = __phy_write(phydev, LAN88XX_EXT_PAGE_TR_CR, buf);
+ if (ret < 0) {
+ pr_warn("Failed to write data in reg\n");
+ goto err;
+ }
+
+ usleep_range(1000, 2000);/* Wait for Data to be written */
+ val = __phy_read(phydev, LAN88XX_EXT_PAGE_TR_CR);
+ if (!(val & 0x8000))
+ pr_warn("TR Register[0x%X] configuration failed\n", regaddr);
+err:
+ return phy_restore_page(phydev, save_page, ret);
+}
+
+static void lan88xx_config_TR_regs(struct phy_device *phydev)
+{
+ int err;
+
+ /* Get access to Channel 0x1, Node 0xF , Register 0x01.
+ * Write 24-bit value 0x12B00A to register. Setting MrvlTrFix1000Kf,
+ * MrvlTrFix1000Kp, MasterEnableTR bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x0F82, 0x12B00A);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x0F82]\n");
+
+ /* Get access to Channel b'10, Node b'1101, Register 0x06.
+ * Write 24-bit value 0xD2C46F to register. Setting SSTrKf1000Slv,
+ * SSTrKp1000Mas bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x168C, 0xD2C46F);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x168C]\n");
+
+ /* Get access to Channel b'10, Node b'1111, Register 0x11.
+ * Write 24-bit value 0x620 to register. Setting rem_upd_done_thresh
+ * bits
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x17A2, 0x620);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x17A2]\n");
+
+ /* Get access to Channel b'10, Node b'1101, Register 0x10.
+ * Write 24-bit value 0xEEFFDD to register. Setting
+ * eee_TrKp1Long_1000, eee_TrKp2Long_1000, eee_TrKp3Long_1000,
+ * eee_TrKp1Short_1000,eee_TrKp2Short_1000, eee_TrKp3Short_1000 bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x16A0, 0xEEFFDD);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x16A0]\n");
+
+ /* Get access to Channel b'10, Node b'1101, Register 0x13.
+ * Write 24-bit value 0x071448 to register. Setting
+ * slv_lpi_tr_tmr_val1, slv_lpi_tr_tmr_val2 bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x16A6, 0x071448);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x16A6]\n");
+
+ /* Get access to Channel b'10, Node b'1101, Register 0x12.
+ * Write 24-bit value 0x13132F to register. Setting
+ * slv_sigdet_timer_val1, slv_sigdet_timer_val2 bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x16A4, 0x13132F);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x16A4]\n");
+
+ /* Get access to Channel b'10, Node b'1101, Register 0x14.
+ * Write 24-bit value 0x0 to register. Setting eee_3level_delay,
+ * eee_TrKf_freeze_delay bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x16A8, 0x0);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x16A8]\n");
+
+ /* Get access to Channel b'01, Node b'1111, Register 0x34.
+ * Write 24-bit value 0x91B06C to register. Setting
+ * FastMseSearchThreshLong1000, FastMseSearchThreshShort1000,
+ * FastMseSearchUpdGain1000 bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x0FE8, 0x91B06C);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x0FE8]\n");
+
+ /* Get access to Channel b'01, Node b'1111, Register 0x3E.
+ * Write 24-bit value 0xC0A028 to register. Setting
+ * FastMseKp2ThreshLong1000, FastMseKp2ThreshShort1000,
+ * FastMseKp2UpdGain1000, FastMseKp2ExitEn1000 bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x0FFC, 0xC0A028);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x0FFC]\n");
+
+ /* Get access to Channel b'01, Node b'1111, Register 0x35.
+ * Write 24-bit value 0x041600 to register. Setting
+ * FastMseSearchPhShNum1000, FastMseSearchClksPerPh1000,
+ * FastMsePhChangeDelay1000 bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x0FEA, 0x041600);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x0FEA]\n");
+
+ /* Get access to Channel b'10, Node b'1101, Register 0x03.
+ * Write 24-bit value 0x000004 to register. Setting TrFreeze bits.
+ */
+ err = lan88xx_TR_reg_set(phydev, 0x1686, 0x000004);
+ if (err < 0)
+ pr_warn("Failed to Set Register[0x1686]\n");
+}
+
static int lan88xx_probe(struct phy_device *phydev)
{
struct device *dev = &phydev->mdio.dev;
@@ -132,6 +287,25 @@ static void lan88xx_set_mdix(struct phy_
phy_write(phydev, LAN88XX_EXT_PAGE_ACCESS, LAN88XX_EXT_PAGE_SPACE_0);
}

+static int lan88xx_config_init(struct phy_device *phydev)
+{
+ int val;
+
+ genphy_config_init(phydev);
+ /*Zerodetect delay enable */
+ val = phy_read_mmd(phydev, MDIO_MMD_PCS,
+ PHY_ARDENNES_MMD_DEV_3_PHY_CFG);
+ val |= PHY_ARDENNES_MMD_DEV_3_PHY_CFG_ZD_DLY_EN_;
+
+ phy_write_mmd(phydev, MDIO_MMD_PCS, PHY_ARDENNES_MMD_DEV_3_PHY_CFG,
+ val);
+
+ /* Config DSP registers */
+ lan88xx_config_TR_regs(phydev);
+
+ return 0;
+}
+
static int lan88xx_config_aneg(struct phy_device *phydev)
{
lan88xx_set_mdix(phydev);
@@ -151,7 +325,7 @@ static struct phy_driver microchip_phy_d
.probe = lan88xx_probe,
.remove = lan88xx_remove,

- .config_init = genphy_config_init,
+ .config_init = lan88xx_config_init,
.config_aneg = lan88xx_config_aneg,

.ack_interrupt = lan88xx_phy_ack_interrupt,
@@ -160,6 +334,8 @@ static struct phy_driver microchip_phy_d
.suspend = lan88xx_suspend,
.resume = genphy_resume,
.set_wol = lan88xx_set_wol,
+ .read_page = lan88xx_read_page,
+ .write_page = lan88xx_write_page,
} };

module_phy_driver(microchip_phy_driver);
--- a/include/linux/microchipphy.h
+++ b/include/linux/microchipphy.h
@@ -70,4 +70,12 @@
#define LAN88XX_MMD3_CHIP_ID (32877)
#define LAN88XX_MMD3_CHIP_REV (32878)

+/* DSP registers */
+#define PHY_ARDENNES_MMD_DEV_3_PHY_CFG (0x806A)
+#define PHY_ARDENNES_MMD_DEV_3_PHY_CFG_ZD_DLY_EN_ (0x2000)
+#define LAN88XX_EXT_PAGE_ACCESS_TR (0x52B5)
+#define LAN88XX_EXT_PAGE_TR_CR 16
+#define LAN88XX_EXT_PAGE_TR_LOW_DATA 17
+#define LAN88XX_EXT_PAGE_TR_HIGH_DATA 18
+
#endif /* _MICROCHIPPHY_H */