diff options
Diffstat (limited to 'target/linux/generic/backport-5.4/740-v5.5-net-phy-avoid-matching-all-ones-clause-45-PHY-IDs.patch')
| -rw-r--r-- | target/linux/generic/backport-5.4/740-v5.5-net-phy-avoid-matching-all-ones-clause-45-PHY-IDs.patch | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/target/linux/generic/backport-5.4/740-v5.5-net-phy-avoid-matching-all-ones-clause-45-PHY-IDs.patch b/target/linux/generic/backport-5.4/740-v5.5-net-phy-avoid-matching-all-ones-clause-45-PHY-IDs.patch new file mode 100644 index 0000000000..81f161e9b1 --- /dev/null +++ b/target/linux/generic/backport-5.4/740-v5.5-net-phy-avoid-matching-all-ones-clause-45-PHY-IDs.patch @@ -0,0 +1,63 @@ +From 1be8018db381200c24854e0c299206c557f76fe0 Mon Sep 17 00:00:00 2001 +From: Russell King <rmk+kernel@armlinux.org.uk> +Date: Mon, 11 Nov 2019 11:58:09 +0000 +Subject: [PATCH 638/660] net: phy: avoid matching all-ones clause 45 PHY IDs + +We currently match clause 45 PHYs using any ID read from a MMD marked +as present in the "Devices in package" registers 5 and 6. However, +this is incorrect. 45.2 says: + + "The definition of the term package is vendor specific and could be + a chip, module, or other similar entity." + +so a package could be more or less than the whole PHY - a PHY could be +made up of several modules instantiated onto a single chip such as the +Marvell 88x3310, or some of the MMDs could be disabled according to +chip configuration, such as the Broadcom 84881. + +In the case of Broadcom 84881, the "Devices in package" registers +contain 0xc000009b, meaning that there is a PHYXS present in the +package, but all registers in MMD 4 return 0xffff. This leads to our +matching code incorrectly binding this PHY to one of our generic PHY +drivers. + +This patch changes the way we determine whether to attempt to match a +MMD identifier, or use it to request a module - if the identifier is +all-ones, then we skip over it. When reading the identifiers, we +initialise phydev->c45_ids.device_ids to all-ones, only reading the +device ID if the "Devices in package" registers indicates we should. + +This avoids the generic drivers incorrectly matching on a PHY ID of +0xffffffff. + +Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> +--- + drivers/net/phy/phy_device.c | 7 +++++-- + 1 file changed, 5 insertions(+), 2 deletions(-) + +--- a/drivers/net/phy/phy_device.c ++++ b/drivers/net/phy/phy_device.c +@@ -335,7 +335,7 @@ static int phy_bus_match(struct device * + + if (phydev->is_c45) { + for (i = 1; i < num_ids; i++) { +- if (!(phydev->c45_ids.devices_in_package & (1 << i))) ++ if (phydev->c45_ids.device_ids[i] == 0xffffffff) + continue; + + if ((phydrv->phy_id & phydrv->phy_id_mask) == +@@ -623,10 +623,13 @@ static int get_phy_id(struct mii_bus *bu + */ + struct phy_device *get_phy_device(struct mii_bus *bus, int addr, bool is_c45) + { +- struct phy_c45_device_ids c45_ids = {0}; ++ struct phy_c45_device_ids c45_ids; + u32 phy_id = 0; + int r; + ++ c45_ids.devices_in_package = 0; ++ memset(c45_ids.device_ids, 0xff, sizeof(c45_ids.device_ids)); ++ + r = get_phy_id(bus, addr, &phy_id, is_c45, &c45_ids); + if (r) + return ERR_PTR(r); |