From f0995f656b225a2d3195727af9b1c460aad91e5c Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 15 Nov 2019 20:08:37 +0000 Subject: [PATCH] net: phy: avoid matching all-ones clause 45 PHY IDs BugLink: https://bugs.launchpad.net/bugs/1858428 [ Upstream commit b95e86d846b63b02ecdc94802ddbeaf9005fb6d9 ] 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 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Seth Forshee --- drivers/net/phy/phy_device.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 1f24083007b9..dceedd4ddab3 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -488,7 +488,7 @@ static int phy_bus_match(struct device *dev, struct device_driver *drv) 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) == @@ -632,7 +632,7 @@ struct phy_device *phy_device_create(struct mii_bus *bus, int addr, u32 phy_id, int i; for (i = 1; i < num_ids; i++) { - if (!(c45_ids->devices_in_package & (1 << i))) + if (c45_ids->device_ids[i] == 0xffffffff) continue; ret = phy_request_driver_module(dev, @@ -812,10 +812,13 @@ static int get_phy_id(struct mii_bus *bus, int addr, u32 *phy_id, */ 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); -- 2.39.5