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Diffstat (limited to 'target/linux/bcm27xx/patches-4.19/950-0193-net-lan78xx-Support-auto-downshift-to-100Mb-s.patch')
-rw-r--r--target/linux/bcm27xx/patches-4.19/950-0193-net-lan78xx-Support-auto-downshift-to-100Mb-s.patch83
1 files changed, 83 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-4.19/950-0193-net-lan78xx-Support-auto-downshift-to-100Mb-s.patch b/target/linux/bcm27xx/patches-4.19/950-0193-net-lan78xx-Support-auto-downshift-to-100Mb-s.patch
new file mode 100644
index 0000000000..c67acaa50d
--- /dev/null
+++ b/target/linux/bcm27xx/patches-4.19/950-0193-net-lan78xx-Support-auto-downshift-to-100Mb-s.patch
@@ -0,0 +1,83 @@
+From a3c59bad71de2b3c09a25fd6ce5e3632c33c4bba Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.org>
+Date: Mon, 26 Nov 2018 19:46:58 +0000
+Subject: [PATCH] net: lan78xx: Support auto-downshift to 100Mb/s
+
+Ethernet cables with faulty or missing pairs (specifically pairs C and
+D) allow auto-negotiation to 1000Mbs, but do not support the successful
+establishment of a link. Add a DT property, "microchip,downshift-after",
+to configure the number of auto-negotiation failures after which it
+falls back to 100Mbs. Valid values are 2, 3, 4, 5 and 0, where 0 means
+never downshift.
+
+Signed-off-by: Phil Elwell <phil@raspberrypi.org>
+---
+ drivers/net/phy/microchip.c | 32 ++++++++++++++++++++++++++++++++
+ include/linux/microchipphy.h | 8 ++++++++
+ 2 files changed, 40 insertions(+)
+
+--- a/drivers/net/phy/microchip.c
++++ b/drivers/net/phy/microchip.c
+@@ -228,6 +228,7 @@ static int lan88xx_probe(struct phy_devi
+ struct device *dev = &phydev->mdio.dev;
+ struct lan88xx_priv *priv;
+ u32 led_modes[4];
++ u32 downshift_after = 0;
+ int len;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+@@ -257,6 +258,37 @@ static int lan88xx_probe(struct phy_devi
+ return -EINVAL;
+ }
+
++ if (!of_property_read_u32(dev->of_node,
++ "microchip,downshift-after",
++ &downshift_after)) {
++ u32 mask = LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_MASK;
++ u32 val = LAN78XX_PHY_CTRL3_AUTO_DOWNSHIFT;
++
++ switch (downshift_after) {
++ case 2:
++ val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_2;
++ break;
++ case 3:
++ val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_3;
++ break;
++ case 4:
++ val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_4;
++ break;
++ case 5:
++ val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_5;
++ break;
++ case 0:
++ /* Disable completely */
++ mask = LAN78XX_PHY_CTRL3_AUTO_DOWNSHIFT;
++ val = 0;
++ break;
++ default:
++ return -EINVAL;
++ }
++ (void)phy_modify_paged(phydev, 1, LAN78XX_PHY_CTRL3,
++ mask, val);
++ }
++
+ /* these values can be used to identify internal PHY */
+ priv->chip_id = phy_read_mmd(phydev, 3, LAN88XX_MMD3_CHIP_ID);
+ priv->chip_rev = phy_read_mmd(phydev, 3, LAN88XX_MMD3_CHIP_REV);
+--- a/include/linux/microchipphy.h
++++ b/include/linux/microchipphy.h
+@@ -73,6 +73,14 @@
+ /* Registers specific to the LAN7800/LAN7850 embedded phy */
+ #define LAN78XX_PHY_LED_MODE_SELECT (0x1D)
+
++#define LAN78XX_PHY_CTRL3 (0x14)
++#define LAN78XX_PHY_CTRL3_AUTO_DOWNSHIFT (0x0010)
++#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_MASK (0x000c)
++#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_2 (0x0000)
++#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_3 (0x0004)
++#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_4 (0x0008)
++#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_5 (0x000c)
++
+ /* DSP registers */
+ #define PHY_ARDENNES_MMD_DEV_3_PHY_CFG (0x806A)
+ #define PHY_ARDENNES_MMD_DEV_3_PHY_CFG_ZD_DLY_EN_ (0x2000)