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Diffstat (limited to 'target/linux/layerscape/patches-5.4/701-net-0264-net-dsa-felix-Fix-CPU-port-assignment-when-not-last-.patch')
-rw-r--r--target/linux/layerscape/patches-5.4/701-net-0264-net-dsa-felix-Fix-CPU-port-assignment-when-not-last-.patch53
1 files changed, 53 insertions, 0 deletions
diff --git a/target/linux/layerscape/patches-5.4/701-net-0264-net-dsa-felix-Fix-CPU-port-assignment-when-not-last-.patch b/target/linux/layerscape/patches-5.4/701-net-0264-net-dsa-felix-Fix-CPU-port-assignment-when-not-last-.patch
new file mode 100644
index 0000000000..972ec164f1
--- /dev/null
+++ b/target/linux/layerscape/patches-5.4/701-net-0264-net-dsa-felix-Fix-CPU-port-assignment-when-not-last-.patch
@@ -0,0 +1,53 @@
+From 93a32fc4f43ae40a2140acd9258faada11a98ec0 Mon Sep 17 00:00:00 2001
+From: Vladimir Oltean <vladimir.oltean@nxp.com>
+Date: Mon, 18 Nov 2019 20:16:57 +0200
+Subject: [PATCH] net: dsa: felix: Fix CPU port assignment when not last port
+
+On the NXP LS1028A, there are 2 Ethernet links between the Felix switch
+and the ENETC:
+- eno2 <-> swp4, at 2.5G
+- eno3 <-> swp5, at 1G
+
+Only one of the above Ethernet port pairs can act as a DSA link for
+tagging.
+
+When adding initial support for the driver, it was tested only on the 1G
+eno3 <-> swp5 interface, due to the necessity of using PHYLIB initially
+(which treats fixed-link interfaces as emulated C22 PHYs, so it doesn't
+support fixed-link speeds higher than 1G).
+
+After making PHYLINK work, it appears that swp4 still can't act as CPU
+port. So it looks like ocelot_set_cpu_port was being called for swp4,
+but then it was called again for swp5, overwriting the CPU port assigned
+in the DT.
+
+It appears that when you call dsa_upstream_port for a port that is not
+defined in the device tree (such as swp5 when using swp4 as CPU port),
+its dp->cpu_dp pointer is not initialized by dsa_tree_setup_default_cpu,
+and this trips up the following condition in dsa_upstream_port:
+
+ if (!cpu_dp)
+ return port;
+
+So the moral of the story is: don't call dsa_upstream_port for a port
+that is not defined in the device tree, and therefore its dsa_port
+structure is not completely initialized (ds->num_ports is still 6).
+
+Fixes: 56051948773e ("net: dsa: ocelot: add driver for Felix switch family")
+Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/ocelot/felix.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/net/dsa/ocelot/felix.c
++++ b/drivers/net/dsa/ocelot/felix.c
+@@ -286,7 +286,7 @@ static int felix_setup(struct dsa_switch
+ for (port = 0; port < ds->num_ports; port++) {
+ ocelot_init_port(ocelot, port);
+
+- if (port == dsa_upstream_port(ds, port))
++ if (dsa_is_cpu_port(ds, port))
+ ocelot_set_cpu_port(ocelot, port,
+ OCELOT_TAG_PREFIX_NONE,
+ OCELOT_TAG_PREFIX_LONG);