From fb16d465f7710d5bfb9bd4d4bee72ba053ab27da Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Mon, 20 Jul 2020 20:26:54 +0300 Subject: [PATCH] net: phy: fix check in get_phy_c45_ids After the patch below, the iteration through the available MMDs is completely short-circuited, and devs_in_pkg remains set to the initial value of zero. Due to devs_in_pkg being zero, the rest of get_phy_c45_ids() is short-circuited too: the following loop never reaches below this point either (it executes "continue" for every device in package, failing to retrieve PHY ID for any of them): /* Now probe Device Identifiers for each device present. */ for (i = 1; i < num_ids; i++) { if (!(devs_in_pkg & (1 << i))) continue; So c45_ids->device_ids remains populated with zeroes. This causes an Aquantia AQR412 PHY (same as any C45 PHY would, in fact) to be probed by the Generic PHY driver. The issue seems to be a case of submitting partially committed work (and therefore testing something other than was submitted). The intention of the patch was to delay exiting the loop until one more condition is reached (the devs_in_pkg read from hardware is either 0, OR mostly f's). So fix the patch to reflect that. Tested with traffic on a LS1028A-QDS, the PHY is now probed correctly using the Aquantia driver. The devs_in_pkg bit field is set to 0xe000009a, and the MMDs that are present have the following IDs: [ 5.600772] libphy: get_phy_c45_ids: device_ids[1]=0x3a1b662 [ 5.618781] libphy: get_phy_c45_ids: device_ids[3]=0x3a1b662 [ 5.630797] libphy: get_phy_c45_ids: device_ids[4]=0x3a1b662 [ 5.654535] libphy: get_phy_c45_ids: device_ids[7]=0x3a1b662 [ 5.791723] libphy: get_phy_c45_ids: device_ids[29]=0x3a1b662 [ 5.804050] libphy: get_phy_c45_ids: device_ids[30]=0x3a1b662 [ 5.816375] libphy: get_phy_c45_ids: device_ids[31]=0x0 [ 7.690237] mscc_felix 0000:00:00.5: PHY [0.5:00] driver [Aquantia AQR412] (irq=POLL) [ 7.704739] mscc_felix 0000:00:00.5: PHY [0.5:01] driver [Aquantia AQR412] (irq=POLL) [ 7.718918] mscc_felix 0000:00:00.5: PHY [0.5:02] driver [Aquantia AQR412] (irq=POLL) [ 7.733044] mscc_felix 0000:00:00.5: PHY [0.5:03] driver [Aquantia AQR412] (irq=POLL) Fixes: bba238ed037c ("net: phy: continue searching for C45 MMDs even if first returned ffff:ffff") Reported-by: Colin King Reported-by: Ioana Ciornei Signed-off-by: Vladimir Oltean Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/phy/phy_device.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 49e98a0..1b95235 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -734,8 +734,8 @@ static int get_phy_c45_ids(struct mii_bus *bus, int addr, /* Find first non-zero Devices In package. Device zero is reserved * for 802.3 c45 complied PHYs, so don't probe it at first. */ - for (i = 1; i < MDIO_MMD_NUM && devs_in_pkg == 0 && - (devs_in_pkg & 0x1fffffff) == 0x1fffffff; i++) { + for (i = 1; i < MDIO_MMD_NUM && (devs_in_pkg == 0 || + (devs_in_pkg & 0x1fffffff) == 0x1fffffff); i++) { if (i == MDIO_MMD_VEND1 || i == MDIO_MMD_VEND2) { /* Check that there is a device present at this * address before reading the devices-in-package -- 2.7.4