kernel: 5.10: backport additional qca8k fixes

Backport 3 additional fixes for qca8k.
- Fix MTU calculation
- Fix a bug with config set to the wrong PAD when secondary cpu port is defined.
- Fix redundant check in parse_port_config

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>

3 files changed, 123 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.10/751-v5.16-net-dsa-qca8k-fix-internal-delay-applied-to-the-wrong-PAD.patch b/target/linux/generic/backport-5.10/751-v5.16-net-dsa-qca8k-fix-internal-delay-applied-to-the-wrong-PAD.patch
new file mode 100644
index 0000000000..df9518d86c
--- /dev/null
+++ b/target/linux/generic/backport-5.10/751-v5.16-net-dsa-qca8k-fix-internal-delay-applied-to-the-wrong-PAD.patch
@@ -0,0 +1,48 @@
+From 3b00a07c2443745d62babfe08dbb2ad8e649526e Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth@gmail.com>
+Date: Fri, 19 Nov 2021 03:03:49 +0100
+Subject: [PATCH] net: dsa: qca8k: fix internal delay applied to the wrong PAD
+ config
+
+With SGMII phy the internal delay is always applied to the PAD0 config.
+This is caused by the falling edge configuration that hardcode the reg
+to PAD0 (as the falling edge bits are present only in PAD0 reg)
+Move the delay configuration before the reg overwrite to correctly apply
+the delay.
+
+Fixes: cef08115846e ("net: dsa: qca8k: set internal delay also for sgmii")
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 12 ++++++------
+ 1 file changed, 6 insertions(+), 6 deletions(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -1433,6 +1433,12 @@ qca8k_phylink_mac_config(struct dsa_swit
+ 
+ 		qca8k_write(priv, QCA8K_REG_SGMII_CTRL, val);
+ 
++		/* From original code is reported port instability as SGMII also
++		 * require delay set. Apply advised values here or take them from DT.
++		 */
++		if (state->interface == PHY_INTERFACE_MODE_SGMII)
++			qca8k_mac_config_setup_internal_delay(priv, cpu_port_index, reg);
++
+ 		/* For qca8327/qca8328/qca8334/qca8338 sgmii is unique and
+ 		 * falling edge is set writing in the PORT0 PAD reg
+ 		 */
+@@ -1455,12 +1461,6 @@ qca8k_phylink_mac_config(struct dsa_swit
+ 					QCA8K_PORT0_PAD_SGMII_TXCLK_FALLING_EDGE,
+ 					val);
+ 
+-		/* From original code is reported port instability as SGMII also
+-		 * require delay set. Apply advised values here or take them from DT.
+-		 */
+-		if (state->interface == PHY_INTERFACE_MODE_SGMII)
+-			qca8k_mac_config_setup_internal_delay(priv, cpu_port_index, reg);
+-
+ 		break;
+ 	default:
+ 		dev_err(ds->dev, "xMII mode %s not supported for port %d\n",
diff --git a/target/linux/generic/backport-5.10/752-v5.16-net-dsa-qca8k-fix-MTU-calculation.patch b/target/linux/generic/backport-5.10/752-v5.16-net-dsa-qca8k-fix-MTU-calculation.patch
new file mode 100644
index 0000000000..7348d93ec4
--- /dev/null
+++ b/target/linux/generic/backport-5.10/752-v5.16-net-dsa-qca8k-fix-MTU-calculation.patch
@@ -0,0 +1,46 @@
+From 65258b9d8cde45689bdc86ca39b50f01f983733b Mon Sep 17 00:00:00 2001
+From: Robert Marko <robert.marko@sartura.hr>
+Date: Fri, 19 Nov 2021 03:03:50 +0100
+Subject: [PATCH] net: dsa: qca8k: fix MTU calculation
+
+qca8k has a global MTU, so its tracking the MTU per port to make sure
+that the largest MTU gets applied.
+Since it uses the frame size instead of MTU the driver MTU change function
+will then add the size of Ethernet header and checksum on top of MTU.
+
+The driver currently populates the per port MTU size as Ethernet frame
+length + checksum which equals 1518.
+
+The issue is that then MTU change function will go through all of the
+ports, find the largest MTU and apply the Ethernet header + checksum on
+top of it again, so for a desired MTU of 1500 you will end up with 1536.
+
+This is obviously incorrect, so to correct it populate the per port struct
+MTU with just the MTU and not include the Ethernet header + checksum size
+as those will be added by the MTU change function.
+
+Fixes: f58d2598cf70 ("net: dsa: qca8k: implement the port MTU callbacks")
+Signed-off-by: Robert Marko <robert.marko@sartura.hr>
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -1256,8 +1256,12 @@ qca8k_setup(struct dsa_switch *ds)
+ 		/* Set initial MTU for every port.
+ 		 * We have only have a general MTU setting. So track
+ 		 * every port and set the max across all port.
++		 * Set per port MTU to 1500 as the MTU change function
++		 * will add the overhead and if its set to 1518 then it
++		 * will apply the overhead again and we will end up with
++		 * MTU of 1536 instead of 1518
+ 		 */
+-		priv->port_mtu[i] = ETH_FRAME_LEN + ETH_FCS_LEN;
++		priv->port_mtu[i] = ETH_DATA_LEN;
+ 	}
+ 
+ 	/* Special GLOBAL_FC_THRESH value are needed for ar8327 switch */
diff --git a/target/linux/generic/backport-5.10/753-net-next-net-dsa-qca8k-remove-redundant-check-in-parse_port_config.patch b/target/linux/generic/backport-5.10/753-net-next-net-dsa-qca8k-remove-redundant-check-in-parse_port_config.patch
new file mode 100644
index 0000000000..f477b1b929
--- /dev/null
+++ b/target/linux/generic/backport-5.10/753-net-next-net-dsa-qca8k-remove-redundant-check-in-parse_port_config.patch
@@ -0,0 +1,29 @@
+From b9133f3ef5a2659730cf47a74bd0a9259f1cf8ff Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth@gmail.com>
+Date: Mon, 22 Nov 2021 16:23:40 +0100
+Subject: net: dsa: qca8k: remove redundant check in parse_port_config
+
+The very next check for port 0 and 6 already makes sure we don't go out
+of bounds with the ports_config delay table.
+Remove the redundant check.
+
+Reported-by: kernel test robot <lkp@intel.com>
+Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -983,7 +983,7 @@ qca8k_parse_port_config(struct qca8k_pri
+ 	u32 delay;
+ 
+ 	/* We have 2 CPU port. Check them */
+-	for (port = 0; port < QCA8K_NUM_PORTS && cpu_port_index < QCA8K_NUM_CPU_PORTS; port++) {
++	for (port = 0; port < QCA8K_NUM_PORTS; port++) {
+ 		/* Skip every other port */
+ 		if (port != 0 && port != 6)
+ 			continue;