Merge branch 'felix-dsa-driver-fixes'

Vladimir Oltean says:

====================
Felix DSA driver fixes

This is an assorted collection of fixes for issues seen on the NXP
LS1028A switch.

- PTP packet drops due to switch congestion result in catastrophic
  damage to the driver's state
- loops are not blocked by STP if using the ocelot-8021q tagger
- driver uses the wrong CPU port when two of them are defined in DT
- module autoloading is broken* with both tagging protocol drivers
  (ocelot and ocelot-8021q)

Changes in v2:
- Stop printing that we aren't going to take TX timestamps if we don't
  have TX timestamping anyway, and we are just carrying PTP frames for a
  cascaded DSA switch.
- Shorten the deferred xmit kthread name so that it fits the 16
  character limit (TASK_COMM_LEN)
====================

Link: https://lore.kernel.org/r/20211012114044.2526146-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 56 insertions, 51 deletions

diff --git a/include/linux/dsa/ocelot.h b/include/linux/dsa/ocelot.h
index 435777a0073c..8ae999f587c4 100644
--- a/include/linux/dsa/ocelot.h
+++ b/include/linux/dsa/ocelot.h
@@ -5,7 +5,28 @@
 #ifndef _NET_DSA_TAG_OCELOT_H
 #define _NET_DSA_TAG_OCELOT_H
 
+#include <linux/kthread.h>
 #include <linux/packing.h>
+#include <linux/skbuff.h>
+
+struct ocelot_skb_cb {
+	struct sk_buff *clone;
+	unsigned int ptp_class; /* valid only for clones */
+	u8 ptp_cmd;
+	u8 ts_id;
+};
+
+#define OCELOT_SKB_CB(skb) \
+	((struct ocelot_skb_cb *)((skb)->cb))
+
+#define IFH_TAG_TYPE_C			0
+#define IFH_TAG_TYPE_S			1
+
+#define IFH_REW_OP_NOOP			0x0
+#define IFH_REW_OP_DSCP			0x1
+#define IFH_REW_OP_ONE_STEP_PTP		0x2
+#define IFH_REW_OP_TWO_STEP_PTP		0x3
+#define IFH_REW_OP_ORIGIN_PTP		0x5
 
 #define OCELOT_TAG_LEN			16
 #define OCELOT_SHORT_PREFIX_LEN		4
@@ -140,6 +161,17 @@
  *         +------+------+------+------+------+------+------+------+
  */
 
+struct felix_deferred_xmit_work {
+	struct dsa_port *dp;
+	struct sk_buff *skb;
+	struct kthread_work work;
+};
+
+struct felix_port {
+	void (*xmit_work_fn)(struct kthread_work *work);
+	struct kthread_worker *xmit_worker;
+};
+
 static inline void ocelot_xfh_get_rew_val(void *extraction, u64 *rew_val)
 {
 	packing(extraction, rew_val, 116, 85, OCELOT_TAG_LEN, UNPACK, 0);
@@ -215,4 +247,21 @@ static inline void ocelot_ifh_set_vid(void *injection, u64 vid)
 	packing(injection, &vid, 11, 0, OCELOT_TAG_LEN, PACK, 0);
 }
 
+/* Determine the PTP REW_OP to use for injecting the given skb */
+static inline u32 ocelot_ptp_rew_op(struct sk_buff *skb)
+{
+	struct sk_buff *clone = OCELOT_SKB_CB(skb)->clone;
+	u8 ptp_cmd = OCELOT_SKB_CB(skb)->ptp_cmd;
+	u32 rew_op = 0;
+
+	if (ptp_cmd == IFH_REW_OP_TWO_STEP_PTP && clone) {
+		rew_op = ptp_cmd;
+		rew_op |= OCELOT_SKB_CB(clone)->ts_id << 3;
+	} else if (ptp_cmd == IFH_REW_OP_ORIGIN_PTP) {
+		rew_op = ptp_cmd;
+	}
+
+	return rew_op;
+}
+
 #endif
diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h
index 06706a9fd5b1..d7055b41982d 100644
--- a/include/soc/mscc/ocelot.h
+++ b/include/soc/mscc/ocelot.h
@@ -89,15 +89,6 @@
 /* Source PGIDs, one per physical port */
 #define PGID_SRC			80
 
-#define IFH_TAG_TYPE_C			0
-#define IFH_TAG_TYPE_S			1
-
-#define IFH_REW_OP_NOOP			0x0
-#define IFH_REW_OP_DSCP			0x1
-#define IFH_REW_OP_ONE_STEP_PTP		0x2
-#define IFH_REW_OP_TWO_STEP_PTP		0x3
-#define IFH_REW_OP_ORIGIN_PTP		0x5
-
 #define OCELOT_NUM_TC			8
 
 #define OCELOT_SPEED_2500		0
@@ -603,10 +594,10 @@ struct ocelot_port {
 	/* The VLAN ID that will be transmitted as untagged, on egress */
 	struct ocelot_vlan		native_vlan;
 
+	unsigned int			ptp_skbs_in_flight;
 	u8				ptp_cmd;
 	struct sk_buff_head		tx_skbs;
 	u8				ts_id;
-	spinlock_t			ts_id_lock;
 
 	phy_interface_t			phy_mode;
 
@@ -680,6 +671,9 @@ struct ocelot {
 	struct ptp_clock		*ptp_clock;
 	struct ptp_clock_info		ptp_info;
 	struct hwtstamp_config		hwtstamp_config;
+	unsigned int			ptp_skbs_in_flight;
+	/* Protects the 2-step TX timestamp ID logic */
+	spinlock_t			ts_id_lock;
 	/* Protects the PTP interface state */
 	struct mutex			ptp_lock;
 	/* Protects the PTP clock */
@@ -692,15 +686,6 @@ struct ocelot_policer {
 	u32 burst; /* bytes */
 };
 
-struct ocelot_skb_cb {
-	struct sk_buff *clone;
-	u8 ptp_cmd;
-	u8 ts_id;
-};
-
-#define OCELOT_SKB_CB(skb) \
-	((struct ocelot_skb_cb *)((skb)->cb))
-
 #define ocelot_read_ix(ocelot, reg, gi, ri) __ocelot_read_ix(ocelot, reg, reg##_GSZ * (gi) + reg##_RSZ * (ri))
 #define ocelot_read_gix(ocelot, reg, gi) __ocelot_read_ix(ocelot, reg, reg##_GSZ * (gi))
 #define ocelot_read_rix(ocelot, reg, ri) __ocelot_read_ix(ocelot, reg, reg##_RSZ * (ri))
@@ -752,8 +737,6 @@ u32 __ocelot_target_read_ix(struct ocelot *ocelot, enum ocelot_target target,
 void __ocelot_target_write_ix(struct ocelot *ocelot, enum ocelot_target target,
 			      u32 val, u32 reg, u32 offset);
 
-#if IS_ENABLED(CONFIG_MSCC_OCELOT_SWITCH_LIB)
-
 /* Packet I/O */
 bool ocelot_can_inject(struct ocelot *ocelot, int grp);
 void ocelot_port_inject_frame(struct ocelot *ocelot, int port, int grp,
@@ -761,36 +744,6 @@ void ocelot_port_inject_frame(struct ocelot *ocelot, int port, int grp,
 int ocelot_xtr_poll_frame(struct ocelot *ocelot, int grp, struct sk_buff **skb);
 void ocelot_drain_cpu_queue(struct ocelot *ocelot, int grp);
 
-u32 ocelot_ptp_rew_op(struct sk_buff *skb);
-#else
-
-static inline bool ocelot_can_inject(struct ocelot *ocelot, int grp)
-{
-	return false;
-}
-
-static inline void ocelot_port_inject_frame(struct ocelot *ocelot, int port,
-					    int grp, u32 rew_op,
-					    struct sk_buff *skb)
-{
-}
-
-static inline int ocelot_xtr_poll_frame(struct ocelot *ocelot, int grp,
-					struct sk_buff **skb)
-{
-	return -EIO;
-}
-
-static inline void ocelot_drain_cpu_queue(struct ocelot *ocelot, int grp)
-{
-}
-
-static inline u32 ocelot_ptp_rew_op(struct sk_buff *skb)
-{
-	return 0;
-}
-#endif
-
 /* Hardware initialization */
 int ocelot_regfields_init(struct ocelot *ocelot,
 			  const struct reg_field *const regfields);
diff --git a/include/soc/mscc/ocelot_ptp.h b/include/soc/mscc/ocelot_ptp.h
index ded497d72bdb..f085884b1fa2 100644
--- a/include/soc/mscc/ocelot_ptp.h
+++ b/include/soc/mscc/ocelot_ptp.h
@@ -13,6 +13,9 @@
 #include <linux/ptp_clock_kernel.h>
 #include <soc/mscc/ocelot.h>
 
+#define OCELOT_MAX_PTP_ID		63
+#define OCELOT_PTP_FIFO_SIZE		128
+
 #define PTP_PIN_CFG_RSZ			0x20
 #define PTP_PIN_TOD_SEC_MSB_RSZ		PTP_PIN_CFG_RSZ
 #define PTP_PIN_TOD_SEC_LSB_RSZ		PTP_PIN_CFG_RSZ