Merge branch 'PTP-clock-source-for-SJA1105-tc-taprio-offload'

Vladimir Oltean says:

====================
PTP clock source for SJA1105 tc-taprio offload

This series makes the IEEE 802.1Qbv egress scheduler of the sja1105
switch use a time reference that is synchronized to the network. This
enables quite a few real Time Sensitive Networking use cases, since in
this mode the switch can offer its clients a TDMA sort of access to the
network, and guaranteed latency for frames that are properly scheduled
based on the common PTP time.

The driver needs to do a 2-part activity:
- Program the gate control list into the static config and upload it
  over SPI to the switch (already supported)
- Write the activation time of the scheduler (base-time) into the
  PTPSCHTM register, and set the PTPSTRTSCH bit.
- Monitor the activation of the scheduler at the planned time and its
  health.

Ok, 3 parts.

The time-aware scheduler cannot be programmed to activate at a time in
the past, and there is some logic to avoid that.

PTPCLKCORP is one of those "black magic" registers that just need to be
written to the length of the cycle. There is a 40-line long comment in
the second patch which explains why.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/sja1105/Kconfig

@@ -28,6 +28,7 @@ config NET_DSA_SJA1105_TAS
 	bool "Support for the Time-Aware Scheduler on NXP SJA1105"
 	depends on NET_DSA_SJA1105 && NET_SCH_TAPRIO
 	depends on NET_SCH_TAPRIO=y || NET_DSA_SJA1105=m
+	depends on NET_DSA_SJA1105_PTP
 	help
 	  This enables support for the TTEthernet-based egress scheduling
 	  engine in the SJA1105 DSA driver, which is controlled using a

drivers/net/dsa/sja1105/sja1105.h

@@ -20,6 +20,11 @@
  */
 #define SJA1105_AGEING_TIME_MS(ms)	((ms) / 10)
 
+typedef enum {
+	SPI_READ = 0,
+	SPI_WRITE = 1,
+} sja1105_spi_rw_mode_t;
+
 #include "sja1105_tas.h"
 #include "sja1105_ptp.h"
 
@@ -35,6 +40,8 @@ struct sja1105_regs {
 	u64 ptp_control;
 	u64 ptpclkval;
 	u64 ptpclkrate;
+	u64 ptpclkcorp;
+	u64 ptpschtm;
 	u64 ptpegr_ts[SJA1105_NUM_PORTS];
 	u64 pad_mii_tx[SJA1105_NUM_PORTS];
 	u64 pad_mii_id[SJA1105_NUM_PORTS];
@@ -71,8 +78,6 @@ struct sja1105_info {
 	const struct sja1105_dynamic_table_ops *dyn_ops;
 	const struct sja1105_table_ops *static_ops;
 	const struct sja1105_regs *regs;
-	int (*ptp_cmd)(const struct dsa_switch *ds,
-		       const struct sja1105_ptp_cmd *cmd);
 	int (*reset_cmd)(const void *ctx, const void *data);
 	int (*setup_rgmii_delay)(const void *ctx, int port);
 	/* Prototypes from include/net/dsa.h */
@@ -80,6 +85,8 @@ struct sja1105_info {
 			   const unsigned char *addr, u16 vid);
 	int (*fdb_del_cmd)(struct dsa_switch *ds, int port,
 			   const unsigned char *addr, u16 vid);
+	void (*ptp_cmd_packing)(u8 *buf, struct sja1105_ptp_cmd *cmd,
+				enum packing_op op);
 	const char *name;
 };
 
@@ -109,11 +116,6 @@ struct sja1105_spi_message {
 	u64 address;
 };
 
-typedef enum {
-	SPI_READ = 0,
-	SPI_WRITE = 1,
-} sja1105_spi_rw_mode_t;
-
 /* From sja1105_main.c */
 enum sja1105_reset_reason {
 	SJA1105_VLAN_FILTERING = 0,

drivers/net/dsa/sja1105/sja1105_ptp.c

@@ -193,42 +193,54 @@ int sja1105_get_ts_info(struct dsa_switch *ds, int port,
 	return 0;
 }
 
-int sja1105et_ptp_cmd(const struct dsa_switch *ds,
-		      const struct sja1105_ptp_cmd *cmd)
+void sja1105et_ptp_cmd_packing(u8 *buf, struct sja1105_ptp_cmd *cmd,
+			       enum packing_op op)
 {
-	const struct sja1105_private *priv = ds->priv;
-	const struct sja1105_regs *regs = priv->info->regs;
 	const int size = SJA1105_SIZE_PTP_CMD;
-	u8 buf[SJA1105_SIZE_PTP_CMD] = {0};
 	/* No need to keep this as part of the structure */
 	u64 valid = 1;
 
-	sja1105_pack(buf, &valid,           31, 31, size);
-	sja1105_pack(buf, &cmd->resptp,      2,  2, size);
-	sja1105_pack(buf, &cmd->corrclk4ts,  1,  1, size);
-	sja1105_pack(buf, &cmd->ptpclkadd,   0,  0, size);
+	sja1105_packing(buf, &valid,           31, 31, size, op);
+	sja1105_packing(buf, &cmd->ptpstrtsch, 30, 30, size, op);
+	sja1105_packing(buf, &cmd->ptpstopsch, 29, 29, size, op);
+	sja1105_packing(buf, &cmd->resptp,      2,  2, size, op);
+	sja1105_packing(buf, &cmd->corrclk4ts,  1,  1, size, op);
+	sja1105_packing(buf, &cmd->ptpclkadd,   0,  0, size, op);
+}
 
-	return sja1105_xfer_buf(priv, SPI_WRITE, regs->ptp_control, buf,
-				SJA1105_SIZE_PTP_CMD);
+void sja1105pqrs_ptp_cmd_packing(u8 *buf, struct sja1105_ptp_cmd *cmd,
+				 enum packing_op op)
+{
+	const int size = SJA1105_SIZE_PTP_CMD;
+	/* No need to keep this as part of the structure */
+	u64 valid = 1;
+
+	sja1105_packing(buf, &valid,           31, 31, size, op);
+	sja1105_packing(buf, &cmd->ptpstrtsch, 30, 30, size, op);
+	sja1105_packing(buf, &cmd->ptpstopsch, 29, 29, size, op);
+	sja1105_packing(buf, &cmd->resptp,      3,  3, size, op);
+	sja1105_packing(buf, &cmd->corrclk4ts,  2,  2, size, op);
+	sja1105_packing(buf, &cmd->ptpclkadd,   0,  0, size, op);
 }
 
-int sja1105pqrs_ptp_cmd(const struct dsa_switch *ds,
-			const struct sja1105_ptp_cmd *cmd)
+int sja1105_ptp_commit(struct dsa_switch *ds, struct sja1105_ptp_cmd *cmd,
+		       sja1105_spi_rw_mode_t rw)
 {
 	const struct sja1105_private *priv = ds->priv;
 	const struct sja1105_regs *regs = priv->info->regs;
-	const int size = SJA1105_SIZE_PTP_CMD;
 	u8 buf[SJA1105_SIZE_PTP_CMD] = {0};
-	/* No need to keep this as part of the structure */
-	u64 valid = 1;
+	int rc;
 
-	sja1105_pack(buf, &valid,           31, 31, size);
-	sja1105_pack(buf, &cmd->resptp,      3,  3, size);
-	sja1105_pack(buf, &cmd->corrclk4ts,  2,  2, size);
-	sja1105_pack(buf, &cmd->ptpclkadd,   0,  0, size);
+	if (rw == SPI_WRITE)
+		priv->info->ptp_cmd_packing(buf, cmd, PACK);
 
-	return sja1105_xfer_buf(priv, SPI_WRITE, regs->ptp_control, buf,
-				SJA1105_SIZE_PTP_CMD);
+	rc = sja1105_xfer_buf(priv, SPI_WRITE, regs->ptp_control, buf,
+			      SJA1105_SIZE_PTP_CMD);
+
+	if (rw == SPI_READ)
+		priv->info->ptp_cmd_packing(buf, cmd, UNPACK);
+
+	return rc;
 }
 
 /* The switch returns partial timestamps (24 bits for SJA1105 E/T, which wrap
@@ -438,8 +450,11 @@ static int sja1105_ptp_reset(struct dsa_switch *ds)
 	mutex_lock(&ptp_data->lock);
 
 	cmd.resptp = 1;
+
 	dev_dbg(ds->dev, "Resetting PTP clock\n");
-	rc = priv->info->ptp_cmd(ds, &cmd);
+	rc = sja1105_ptp_commit(ds, &cmd, SPI_WRITE);
+
+	sja1105_tas_clockstep(priv->ds);
 
 	mutex_unlock(&ptp_data->lock);
 
@@ -495,7 +510,7 @@ static int sja1105_ptp_mode_set(struct sja1105_private *priv,
 
 	ptp_data->cmd.ptpclkadd = mode;
 
-	return priv->info->ptp_cmd(priv->ds, &ptp_data->cmd);
+	return sja1105_ptp_commit(priv->ds, &ptp_data->cmd, SPI_WRITE);
 }
 
 /* Write to PTPCLKVAL while PTPCLKADD is 0 */
@@ -512,7 +527,11 @@ int __sja1105_ptp_settime(struct dsa_switch *ds, u64 ns,
 		return rc;
 	}
 
-	return sja1105_ptpclkval_write(priv, ticks, ptp_sts);
+	rc = sja1105_ptpclkval_write(priv, ticks, ptp_sts);
+
+	sja1105_tas_clockstep(priv->ds);
+
+	return rc;
 }
 
 static int sja1105_ptp_settime(struct ptp_clock_info *ptp,
@@ -554,6 +573,8 @@ static int sja1105_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
 	rc = sja1105_xfer_u32(priv, SPI_WRITE, regs->ptpclkrate, &clkrate32,
 			      NULL);
 
+	sja1105_tas_adjfreq(priv->ds);
+
 	mutex_unlock(&ptp_data->lock);
 
 	return rc;
@@ -572,7 +593,11 @@ int __sja1105_ptp_adjtime(struct dsa_switch *ds, s64 delta)
 		return rc;
 	}
 
-	return sja1105_ptpclkval_write(priv, ticks, NULL);
+	rc = sja1105_ptpclkval_write(priv, ticks, NULL);
+
+	sja1105_tas_clockstep(priv->ds);
+
+	return rc;
 }
 
 static int sja1105_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)

drivers/net/dsa/sja1105/sja1105_ptp.h

@@ -22,6 +22,8 @@ static inline s64 sja1105_ticks_to_ns(s64 ticks)
 }
 
 struct sja1105_ptp_cmd {
+	u64 ptpstrtsch;		/* start schedule */
+	u64 ptpstopsch;		/* stop schedule */
 	u64 resptp;		/* reset */
 	u64 corrclk4ts;		/* use the corrected clock for timestamps */
 	u64 ptpclkadd;		/* enum sja1105_ptp_clk_mode */
@@ -39,11 +41,11 @@ int sja1105_ptp_clock_register(struct dsa_switch *ds);
 
 void sja1105_ptp_clock_unregister(struct dsa_switch *ds);
 
-int sja1105et_ptp_cmd(const struct dsa_switch *ds,
-		      const struct sja1105_ptp_cmd *cmd);
+void sja1105et_ptp_cmd_packing(u8 *buf, struct sja1105_ptp_cmd *cmd,
+			       enum packing_op op);
 
-int sja1105pqrs_ptp_cmd(const struct dsa_switch *ds,
-			const struct sja1105_ptp_cmd *cmd);
+void sja1105pqrs_ptp_cmd_packing(u8 *buf, struct sja1105_ptp_cmd *cmd,
+				 enum packing_op op);
 
 int sja1105_get_ts_info(struct dsa_switch *ds, int port,
 			struct ethtool_ts_info *ts);
@@ -69,6 +71,9 @@ int __sja1105_ptp_settime(struct dsa_switch *ds, u64 ns,
 
 int __sja1105_ptp_adjtime(struct dsa_switch *ds, s64 delta);
 
+int sja1105_ptp_commit(struct dsa_switch *ds, struct sja1105_ptp_cmd *cmd,
+		       sja1105_spi_rw_mode_t rw);
+
 #else
 
 struct sja1105_ptp_cmd;
@@ -110,9 +115,16 @@ static inline int __sja1105_ptp_adjtime(struct dsa_switch *ds, s64 delta)
 	return 0;
 }
 
-#define sja1105et_ptp_cmd NULL
+static inline int sja1105_ptp_commit(struct dsa_switch *ds,
+				     struct sja1105_ptp_cmd *cmd,
+				     sja1105_spi_rw_mode_t rw)
+{
+	return 0;
+}
+
+#define sja1105et_ptp_cmd_packing NULL
 
-#define sja1105pqrs_ptp_cmd NULL
+#define sja1105pqrs_ptp_cmd_packing NULL
 
 #define sja1105_get_ts_info NULL
 

drivers/net/dsa/sja1105/sja1105_spi.c

@@ -539,9 +539,11 @@ static struct sja1105_regs sja1105et_regs = {
 	.rmii_ref_clk = {0x100015, 0x10001C, 0x100023, 0x10002A, 0x100031},
 	.rmii_ext_tx_clk = {0x100018, 0x10001F, 0x100026, 0x10002D, 0x100034},
 	.ptpegr_ts = {0xC0, 0xC2, 0xC4, 0xC6, 0xC8},
+	.ptpschtm = 0x12, /* Spans 0x12 to 0x13 */
 	.ptp_control = 0x17,
 	.ptpclkval = 0x18, /* Spans 0x18 to 0x19 */
 	.ptpclkrate = 0x1A,
+	.ptpclkcorp = 0x1D,
 };
 
 static struct sja1105_regs sja1105pqrs_regs = {
@@ -569,9 +571,11 @@ static struct sja1105_regs sja1105pqrs_regs = {
 	.rmii_ext_tx_clk = {0x100017, 0x10001D, 0x100023, 0x100029, 0x10002F},
 	.qlevel = {0x604, 0x614, 0x624, 0x634, 0x644},
 	.ptpegr_ts = {0xC0, 0xC4, 0xC8, 0xCC, 0xD0},
+	.ptpschtm = 0x13, /* Spans 0x13 to 0x14 */
 	.ptp_control = 0x18,
 	.ptpclkval = 0x19,
 	.ptpclkrate = 0x1B,
+	.ptpclkcorp = 0x1E,
 };
 
 struct sja1105_info sja1105e_info = {
@@ -584,7 +588,7 @@ struct sja1105_info sja1105e_info = {
 	.reset_cmd		= sja1105et_reset_cmd,
 	.fdb_add_cmd		= sja1105et_fdb_add,
 	.fdb_del_cmd		= sja1105et_fdb_del,
-	.ptp_cmd		= sja1105et_ptp_cmd,
+	.ptp_cmd_packing	= sja1105et_ptp_cmd_packing,
 	.regs			= &sja1105et_regs,
 	.name			= "SJA1105E",
 };
@@ -598,7 +602,7 @@ struct sja1105_info sja1105t_info = {
 	.reset_cmd		= sja1105et_reset_cmd,
 	.fdb_add_cmd		= sja1105et_fdb_add,
 	.fdb_del_cmd		= sja1105et_fdb_del,
-	.ptp_cmd		= sja1105et_ptp_cmd,
+	.ptp_cmd_packing	= sja1105et_ptp_cmd_packing,
 	.regs			= &sja1105et_regs,
 	.name			= "SJA1105T",
 };
@@ -613,7 +617,7 @@ struct sja1105_info sja1105p_info = {
 	.reset_cmd		= sja1105pqrs_reset_cmd,
 	.fdb_add_cmd		= sja1105pqrs_fdb_add,
 	.fdb_del_cmd		= sja1105pqrs_fdb_del,
-	.ptp_cmd		= sja1105pqrs_ptp_cmd,
+	.ptp_cmd_packing	= sja1105pqrs_ptp_cmd_packing,
 	.regs			= &sja1105pqrs_regs,
 	.name			= "SJA1105P",
 };
@@ -628,7 +632,7 @@ struct sja1105_info sja1105q_info = {
 	.reset_cmd		= sja1105pqrs_reset_cmd,
 	.fdb_add_cmd		= sja1105pqrs_fdb_add,
 	.fdb_del_cmd		= sja1105pqrs_fdb_del,
-	.ptp_cmd		= sja1105pqrs_ptp_cmd,
+	.ptp_cmd_packing	= sja1105pqrs_ptp_cmd_packing,
 	.regs			= &sja1105pqrs_regs,
 	.name			= "SJA1105Q",
 };
@@ -643,7 +647,7 @@ struct sja1105_info sja1105r_info = {
 	.reset_cmd		= sja1105pqrs_reset_cmd,
 	.fdb_add_cmd		= sja1105pqrs_fdb_add,
 	.fdb_del_cmd		= sja1105pqrs_fdb_del,
-	.ptp_cmd		= sja1105pqrs_ptp_cmd,
+	.ptp_cmd_packing	= sja1105pqrs_ptp_cmd_packing,
 	.regs			= &sja1105pqrs_regs,
 	.name			= "SJA1105R",
 };
@@ -659,6 +663,6 @@ struct sja1105_info sja1105s_info = {
 	.reset_cmd		= sja1105pqrs_reset_cmd,
 	.fdb_add_cmd		= sja1105pqrs_fdb_add,
 	.fdb_del_cmd		= sja1105pqrs_fdb_del,
-	.ptp_cmd		= sja1105pqrs_ptp_cmd,
+	.ptp_cmd_packing	= sja1105pqrs_ptp_cmd_packing,
 	.name			= "SJA1105S",
 };

drivers/net/dsa/sja1105/sja1105_tas.h

@@ -8,8 +8,27 @@
 
 #if IS_ENABLED(CONFIG_NET_DSA_SJA1105_TAS)
 
+enum sja1105_tas_state {
+	SJA1105_TAS_STATE_DISABLED,
+	SJA1105_TAS_STATE_ENABLED_NOT_RUNNING,
+	SJA1105_TAS_STATE_RUNNING,
+};
+
+enum sja1105_ptp_op {
+	SJA1105_PTP_NONE,
+	SJA1105_PTP_CLOCKSTEP,
+	SJA1105_PTP_ADJUSTFREQ,
+};
+
 struct sja1105_tas_data {
 	struct tc_taprio_qopt_offload *offload[SJA1105_NUM_PORTS];
+	enum sja1105_tas_state state;
+	enum sja1105_ptp_op last_op;
+	struct work_struct tas_work;
+	s64 earliest_base_time;
+	s64 oper_base_time;
+	u64 max_cycle_time;
+	bool enabled;
 };
 
 int sja1105_setup_tc_taprio(struct dsa_switch *ds, int port,
@@ -19,6 +38,10 @@ void sja1105_tas_setup(struct dsa_switch *ds);
 
 void sja1105_tas_teardown(struct dsa_switch *ds);
 
+void sja1105_tas_clockstep(struct dsa_switch *ds);
+
+void sja1105_tas_adjfreq(struct dsa_switch *ds);
+
 #else
 
 /* C doesn't allow empty structures, bah! */
@@ -36,6 +59,10 @@ static inline void sja1105_tas_setup(struct dsa_switch *ds) { }
 
 static inline void sja1105_tas_teardown(struct dsa_switch *ds) { }
 
+static inline void sja1105_tas_clockstep(struct dsa_switch *ds) { }
+
+static inline void sja1105_tas_adjfreq(struct dsa_switch *ds) { }
+
 #endif /* IS_ENABLED(CONFIG_NET_DSA_SJA1105_TAS) */
 
 #endif /* _SJA1105_TAS_H */