Merge branch 'support-external-snapshots-on-dwmac1000'

Maxime Chevallier says:

====================
Support external snapshots on dwmac1000

The main change since v3 is the move of the fifo flush wait in the
ptp_clock_info enable() function within the mutex that protects the ptp
registers. Thanks Jakub and Paolo for spotting this.

This series also aggregates Daniel's reviews, except for the patch 4
which was modified since then.

This series is another take on the previous work [1] done by
Alexis Lothoré, that fixes the support for external snapshots
timestamping in GMAC3-based devices.

Details on why this is needed are mentionned on the cover [2] from V1.

[1]: https://lore.kernel.org/netdev/20230616100409.164583-1-alexis.lothore@bootlin.com/
[2]: https://lore.kernel.org/netdev/20241029115419.1160201-1-maxime.chevallier@bootlin.com/

Link to V1: https://lore.kernel.org/netdev/20241029115419.1160201-1-maxime.chevallier@bootlin.com/
Link to V2: https://lore.kernel.org/netdev/20241104170251.2202270-1-maxime.chevallier@bootlin.com/
Link to V3: https://lore.kernel.org/netdev/20241106090331.56519-1-maxime.chevallier@bootlin.com/
====================

Link: https://patch.msgid.link/20241112170658.2388529-1-maxime.chevallier@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

8 files changed, 196 insertions, 11 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
index 684489156dce..1367fa5c9b8e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/common.h
+++ b/drivers/net/ethernet/stmicro/stmmac/common.h
@@ -549,8 +549,12 @@ extern const struct stmmac_desc_ops ndesc_ops;
 struct mac_device_info;
 
 extern const struct stmmac_hwtimestamp stmmac_ptp;
+extern const struct stmmac_hwtimestamp dwmac1000_ptp;
 extern const struct stmmac_mode_ops dwmac4_ring_mode_ops;
 
+extern const struct ptp_clock_info stmmac_ptp_clock_ops;
+extern const struct ptp_clock_info dwmac1000_ptp_clock_ops;
+
 struct mac_link {
 	u32 caps;
 	u32 speed_mask;
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c
index 0745117d5872..248b30d7b864 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c
@@ -485,6 +485,7 @@ static int socfpga_dwmac_probe(struct platform_device *pdev)
 	plat_dat->pcs_init = socfpga_dwmac_pcs_init;
 	plat_dat->pcs_exit = socfpga_dwmac_pcs_exit;
 	plat_dat->select_pcs = socfpga_dwmac_select_pcs;
+	plat_dat->has_gmac = true;
 
 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
 	if (ret)
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h b/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
index 4296ddda8aaa..600fea8f712f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
@@ -329,5 +329,17 @@ enum rtc_control {
 #define GMAC_MMC_RX_CSUM_OFFLOAD   0x208
 #define GMAC_EXTHASH_BASE  0x500
 
+/* PTP and timestamping registers */
+
+#define GMAC3_X_ATSNS       GENMASK(19, 16)
+#define GMAC3_X_ATSNS_SHIFT 16
+
+#define GMAC_PTP_TCR_ATSFC	BIT(24)
+#define GMAC_PTP_TCR_ATSEN0	BIT(25)
+
+#define GMAC3_X_TIMESTAMP_STATUS	0x28
+#define GMAC_PTP_ATNR	0x30
+#define GMAC_PTP_ATSR	0x34
+
 extern const struct stmmac_dma_ops dwmac1000_dma_ops;
 #endif /* __DWMAC1000_H__ */
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
index d413d76a8936..96bcda0856ec 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
@@ -18,6 +18,7 @@
 #include <linux/io.h>
 #include "stmmac.h"
 #include "stmmac_pcs.h"
+#include "stmmac_ptp.h"
 #include "dwmac1000.h"
 
 static void dwmac1000_core_init(struct mac_device_info *hw,
@@ -551,3 +552,103 @@ int dwmac1000_setup(struct stmmac_priv *priv)
 
 	return 0;
 }
+
+/* DWMAC 1000 HW Timestaming ops */
+
+void dwmac1000_get_ptptime(void __iomem *ptpaddr, u64 *ptp_time)
+{
+	u64 ns;
+
+	ns = readl(ptpaddr + GMAC_PTP_ATNR);
+	ns += readl(ptpaddr + GMAC_PTP_ATSR) * NSEC_PER_SEC;
+
+	*ptp_time = ns;
+}
+
+void dwmac1000_timestamp_interrupt(struct stmmac_priv *priv)
+{
+	struct ptp_clock_event event;
+	u32 ts_status, num_snapshot;
+	unsigned long flags;
+	u64 ptp_time;
+	int i;
+
+	/* Clears the timestamp interrupt */
+	ts_status = readl(priv->ptpaddr + GMAC3_X_TIMESTAMP_STATUS);
+
+	if (!(priv->plat->flags & STMMAC_FLAG_EXT_SNAPSHOT_EN))
+		return;
+
+	num_snapshot = (ts_status & GMAC3_X_ATSNS) >> GMAC3_X_ATSNS_SHIFT;
+
+	for (i = 0; i < num_snapshot; i++) {
+		read_lock_irqsave(&priv->ptp_lock, flags);
+		stmmac_get_ptptime(priv, priv->ptpaddr, &ptp_time);
+		read_unlock_irqrestore(&priv->ptp_lock, flags);
+
+		event.type = PTP_CLOCK_EXTTS;
+		event.index = 0;
+		event.timestamp = ptp_time;
+		ptp_clock_event(priv->ptp_clock, &event);
+	}
+}
+
+/* DWMAC 1000 ptp_clock_info ops */
+
+static void dwmac1000_timestamp_interrupt_cfg(struct stmmac_priv *priv, bool en)
+{
+	void __iomem *ioaddr = priv->ioaddr;
+
+	u32 intr_mask = readl(ioaddr + GMAC_INT_MASK);
+
+	if (en)
+		intr_mask &= ~GMAC_INT_DISABLE_TIMESTAMP;
+	else
+		intr_mask |= GMAC_INT_DISABLE_TIMESTAMP;
+
+	writel(intr_mask, ioaddr + GMAC_INT_MASK);
+}
+
+int dwmac1000_ptp_enable(struct ptp_clock_info *ptp,
+			 struct ptp_clock_request *rq, int on)
+{
+	struct stmmac_priv *priv =
+	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
+	void __iomem *ptpaddr = priv->ptpaddr;
+	int ret = -EOPNOTSUPP;
+	u32 tcr_val;
+
+	switch (rq->type) {
+	case PTP_CLK_REQ_EXTTS:
+		mutex_lock(&priv->aux_ts_lock);
+		tcr_val = readl(ptpaddr + PTP_TCR);
+
+		if (on) {
+			tcr_val |= GMAC_PTP_TCR_ATSEN0;
+			tcr_val |= GMAC_PTP_TCR_ATSFC;
+			priv->plat->flags |= STMMAC_FLAG_EXT_SNAPSHOT_EN;
+		} else {
+			tcr_val &= ~GMAC_PTP_TCR_ATSEN0;
+			priv->plat->flags &= ~STMMAC_FLAG_EXT_SNAPSHOT_EN;
+		}
+
+		netdev_dbg(priv->dev, "Auxiliary Snapshot %s.\n",
+			   on ? "enabled" : "disabled");
+		writel(tcr_val, ptpaddr + PTP_TCR);
+
+		/* wait for auxts fifo clear to finish */
+		ret = readl_poll_timeout(ptpaddr + PTP_TCR, tcr_val,
+					 !(tcr_val & GMAC_PTP_TCR_ATSFC),
+					 10, 10000);
+
+		mutex_unlock(&priv->aux_ts_lock);
+
+		dwmac1000_timestamp_interrupt_cfg(priv, on);
+		break;
+
+	default:
+		break;
+	}
+
+	return ret;
+}
diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.c b/drivers/net/ethernet/stmicro/stmmac/hwif.c
index cfc50289aed6..a72d336a8350 100644
--- a/drivers/net/ethernet/stmicro/stmmac/hwif.c
+++ b/drivers/net/ethernet/stmicro/stmmac/hwif.c
@@ -113,6 +113,7 @@ static const struct stmmac_hwif_entry {
 	const void *dma;
 	const void *mac;
 	const void *hwtimestamp;
+	const void *ptp;
 	const void *mode;
 	const void *tc;
 	const void *mmc;
@@ -133,7 +134,8 @@ static const struct stmmac_hwif_entry {
 		.desc = NULL,
 		.dma = &dwmac100_dma_ops,
 		.mac = &dwmac100_ops,
-		.hwtimestamp = &stmmac_ptp,
+		.hwtimestamp = &dwmac1000_ptp,
+		.ptp = &dwmac1000_ptp_clock_ops,
 		.mode = NULL,
 		.tc = NULL,
 		.mmc = &dwmac_mmc_ops,
@@ -151,7 +153,8 @@ static const struct stmmac_hwif_entry {
 		.desc = NULL,
 		.dma = &dwmac1000_dma_ops,
 		.mac = &dwmac1000_ops,
-		.hwtimestamp = &stmmac_ptp,
+		.hwtimestamp = &dwmac1000_ptp,
+		.ptp = &dwmac1000_ptp_clock_ops,
 		.mode = NULL,
 		.tc = NULL,
 		.mmc = &dwmac_mmc_ops,
@@ -171,6 +174,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwmac4_dma_ops,
 		.mac = &dwmac4_ops,
 		.hwtimestamp = &stmmac_ptp,
+		.ptp = &stmmac_ptp_clock_ops,
 		.mode = NULL,
 		.tc = &dwmac4_tc_ops,
 		.mmc = &dwmac_mmc_ops,
@@ -192,6 +196,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwmac4_dma_ops,
 		.mac = &dwmac410_ops,
 		.hwtimestamp = &stmmac_ptp,
+		.ptp = &stmmac_ptp_clock_ops,
 		.mode = &dwmac4_ring_mode_ops,
 		.tc = &dwmac510_tc_ops,
 		.mmc = &dwmac_mmc_ops,
@@ -213,6 +218,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwmac410_dma_ops,
 		.mac = &dwmac410_ops,
 		.hwtimestamp = &stmmac_ptp,
+		.ptp = &stmmac_ptp_clock_ops,
 		.mode = &dwmac4_ring_mode_ops,
 		.tc = &dwmac510_tc_ops,
 		.mmc = &dwmac_mmc_ops,
@@ -234,6 +240,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwmac410_dma_ops,
 		.mac = &dwmac510_ops,
 		.hwtimestamp = &stmmac_ptp,
+		.ptp = &stmmac_ptp_clock_ops,
 		.mode = &dwmac4_ring_mode_ops,
 		.tc = &dwmac510_tc_ops,
 		.mmc = &dwmac_mmc_ops,
@@ -256,6 +263,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwxgmac210_dma_ops,
 		.mac = &dwxgmac210_ops,
 		.hwtimestamp = &stmmac_ptp,
+		.ptp = &stmmac_ptp_clock_ops,
 		.mode = NULL,
 		.tc = &dwxgmac_tc_ops,
 		.mmc = &dwxgmac_mmc_ops,
@@ -278,6 +286,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwxgmac210_dma_ops,
 		.mac = &dwxlgmac2_ops,
 		.hwtimestamp = &stmmac_ptp,
+		.ptp = &stmmac_ptp_clock_ops,
 		.mode = NULL,
 		.tc = &dwxgmac_tc_ops,
 		.mmc = &dwxgmac_mmc_ops,
@@ -362,6 +371,8 @@ int stmmac_hwif_init(struct stmmac_priv *priv)
 		priv->fpe_cfg.reg = entry->regs.fpe_reg;
 		priv->ptpaddr = priv->ioaddr + entry->regs.ptp_off;
 		priv->mmcaddr = priv->ioaddr + entry->regs.mmc_off;
+		memcpy(&priv->ptp_clock_ops, entry->ptp,
+		       sizeof(struct ptp_clock_info));
 		if (entry->est)
 			priv->estaddr = priv->ioaddr + entry->regs.est_off;
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
index 5ef52ef2698f..0f59aa982604 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
@@ -18,9 +18,22 @@
 #include "dwmac4.h"
 #include "stmmac.h"
 
+#define STMMAC_HWTS_CFG_MASK	(PTP_TCR_TSENA | PTP_TCR_TSCFUPDT | \
+				 PTP_TCR_TSINIT | PTP_TCR_TSUPDT | \
+				 PTP_TCR_TSCTRLSSR | PTP_TCR_SNAPTYPSEL_1 | \
+				 PTP_TCR_TSIPV4ENA | PTP_TCR_TSIPV6ENA | \
+				 PTP_TCR_TSEVNTENA | PTP_TCR_TSMSTRENA | \
+				 PTP_TCR_TSVER2ENA | PTP_TCR_TSIPENA | \
+				 PTP_TCR_TSTRIG | PTP_TCR_TSENALL)
+
 static void config_hw_tstamping(void __iomem *ioaddr, u32 data)
 {
-	writel(data, ioaddr + PTP_TCR);
+	u32 regval = readl(ioaddr + PTP_TCR);
+
+	regval &= ~STMMAC_HWTS_CFG_MASK;
+	regval |= data;
+
+	writel(regval, ioaddr + PTP_TCR);
 }
 
 static void config_sub_second_increment(void __iomem *ioaddr,
@@ -269,3 +282,14 @@ const struct stmmac_hwtimestamp stmmac_ptp = {
 	.timestamp_interrupt = timestamp_interrupt,
 	.hwtstamp_correct_latency = hwtstamp_correct_latency,
 };
+
+const struct stmmac_hwtimestamp dwmac1000_ptp = {
+	.config_hw_tstamping = config_hw_tstamping,
+	.init_systime = init_systime,
+	.config_sub_second_increment = config_sub_second_increment,
+	.config_addend = config_addend,
+	.adjust_systime = adjust_systime,
+	.get_systime = get_systime,
+	.get_ptptime = dwmac1000_get_ptptime,
+	.timestamp_interrupt = dwmac1000_timestamp_interrupt,
+};
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
index a6b1de9a251d..429b2d357813 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
@@ -9,7 +9,6 @@
 *******************************************************************************/
 #include "stmmac.h"
 #include "stmmac_ptp.h"
-#include "dwmac4.h"
 
 /**
  * stmmac_adjust_freq
@@ -265,7 +264,7 @@ static int stmmac_getcrosststamp(struct ptp_clock_info *ptp,
 }
 
 /* structure describing a PTP hardware clock */
-static struct ptp_clock_info stmmac_ptp_clock_ops = {
+const struct ptp_clock_info stmmac_ptp_clock_ops = {
 	.owner = THIS_MODULE,
 	.name = "stmmac ptp",
 	.max_adj = 62500000,
@@ -282,6 +281,24 @@ static struct ptp_clock_info stmmac_ptp_clock_ops = {
 	.getcrosststamp = stmmac_getcrosststamp,
 };
 
+/* structure describing a PTP hardware clock */
+const struct ptp_clock_info dwmac1000_ptp_clock_ops = {
+	.owner = THIS_MODULE,
+	.name = "stmmac ptp",
+	.max_adj = 62500000,
+	.n_alarm = 0,
+	.n_ext_ts = 1,
+	.n_per_out = 0,
+	.n_pins = 0,
+	.pps = 0,
+	.adjfine = stmmac_adjust_freq,
+	.adjtime = stmmac_adjust_time,
+	.gettime64 = stmmac_get_time,
+	.settime64 = stmmac_set_time,
+	.enable = dwmac1000_ptp_enable,
+	.getcrosststamp = stmmac_getcrosststamp,
+};
+
 /**
  * stmmac_ptp_register
  * @priv: driver private structure
@@ -298,20 +315,25 @@ void stmmac_ptp_register(struct stmmac_priv *priv)
 		priv->pps[i].available = true;
 	}
 
-	if (priv->plat->ptp_max_adj)
-		stmmac_ptp_clock_ops.max_adj = priv->plat->ptp_max_adj;
-
 	/* Calculate the clock domain crossing (CDC) error if necessary */
 	priv->plat->cdc_error_adj = 0;
 	if (priv->plat->has_gmac4 && priv->plat->clk_ptp_rate)
 		priv->plat->cdc_error_adj = (2 * NSEC_PER_SEC) / priv->plat->clk_ptp_rate;
 
-	stmmac_ptp_clock_ops.n_per_out = priv->dma_cap.pps_out_num;
-	stmmac_ptp_clock_ops.n_ext_ts = priv->dma_cap.aux_snapshot_n;
+	/* Update the ptp clock parameters based on feature discovery, when
+	 * available
+	 */
+	if (priv->dma_cap.pps_out_num)
+		priv->ptp_clock_ops.n_per_out = priv->dma_cap.pps_out_num;
+
+	if (priv->dma_cap.aux_snapshot_n)
+		priv->ptp_clock_ops.n_ext_ts = priv->dma_cap.aux_snapshot_n;
+
+	if (priv->plat->ptp_max_adj)
+		priv->ptp_clock_ops.max_adj = priv->plat->ptp_max_adj;
 
 	rwlock_init(&priv->ptp_lock);
 	mutex_init(&priv->aux_ts_lock);
-	priv->ptp_clock_ops = stmmac_ptp_clock_ops;
 
 	priv->ptp_clock = ptp_clock_register(&priv->ptp_clock_ops,
 					     priv->device);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h
index fce3fba2ffd2..4cc70480ce0f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h
@@ -94,4 +94,14 @@ enum aux_snapshot {
 	AUX_SNAPSHOT3 = 0x80,
 };
 
+struct ptp_clock_info;
+struct ptp_clock_request;
+struct stmmac_priv;
+
+int dwmac1000_ptp_enable(struct ptp_clock_info *ptp,
+			 struct ptp_clock_request *rq, int on);
+
+void dwmac1000_get_ptptime(void __iomem *ptpaddr, u64 *ptp_time);
+void dwmac1000_timestamp_interrupt(struct stmmac_priv *priv);
+
 #endif	/* __STMMAC_PTP_H__ */