1 files changed, 224 insertions, 0 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
new file mode 100644
index 000000000..8b50f0305
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*******************************************************************************
+  Copyright (C) 2013  Vayavya Labs Pvt Ltd
+
+  This implements all the API for managing HW timestamp & PTP.
+
+
+  Author: Rayagond Kokatanur <rayagond@vayavyalabs.com>
+  Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
+*******************************************************************************/
+
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/delay.h>
+#include <linux/ptp_clock_kernel.h>
+#include "common.h"
+#include "stmmac_ptp.h"
+#include "dwmac4.h"
+#include "stmmac.h"
+
+static void config_hw_tstamping(void __iomem *ioaddr, u32 data)
+{
+	writel(data, ioaddr + PTP_TCR);
+}
+
+static void config_sub_second_increment(void __iomem *ioaddr,
+		u32 ptp_clock, int gmac4, u32 *ssinc)
+{
+	u32 value = readl(ioaddr + PTP_TCR);
+	unsigned long data;
+	u32 reg_value;
+
+	/* For GMAC3.x, 4.x versions, in "fine adjustement mode" set sub-second
+	 * increment to twice the number of nanoseconds of a clock cycle.
+	 * The calculation of the default_addend value by the caller will set it
+	 * to mid-range = 2^31 when the remainder of this division is zero,
+	 * which will make the accumulator overflow once every 2 ptp_clock
+	 * cycles, adding twice the number of nanoseconds of a clock cycle :
+	 * 2000000000ULL / ptp_clock.
+	 */
+	if (value & PTP_TCR_TSCFUPDT)
+		data = (2000000000ULL / ptp_clock);
+	else
+		data = (1000000000ULL / ptp_clock);
+
+	/* 0.465ns accuracy */
+	if (!(value & PTP_TCR_TSCTRLSSR))
+		data = (data * 1000) / 465;
+
+	if (data > PTP_SSIR_SSINC_MAX)
+		data = PTP_SSIR_SSINC_MAX;
+
+	reg_value = data;
+	if (gmac4)
+		reg_value <<= GMAC4_PTP_SSIR_SSINC_SHIFT;
+
+	writel(reg_value, ioaddr + PTP_SSIR);
+
+	if (ssinc)
+		*ssinc = data;
+}
+
+static int init_systime(void __iomem *ioaddr, u32 sec, u32 nsec)
+{
+	u32 value;
+
+	writel(sec, ioaddr + PTP_STSUR);
+	writel(nsec, ioaddr + PTP_STNSUR);
+	/* issue command to initialize the system time value */
+	value = readl(ioaddr + PTP_TCR);
+	value |= PTP_TCR_TSINIT;
+	writel(value, ioaddr + PTP_TCR);
+
+	/* wait for present system time initialize to complete */
+	return readl_poll_timeout_atomic(ioaddr + PTP_TCR, value,
+				 !(value & PTP_TCR_TSINIT),
+				 10, 100000);
+}
+
+static int config_addend(void __iomem *ioaddr, u32 addend)
+{
+	u32 value;
+	int limit;
+
+	writel(addend, ioaddr + PTP_TAR);
+	/* issue command to update the addend value */
+	value = readl(ioaddr + PTP_TCR);
+	value |= PTP_TCR_TSADDREG;
+	writel(value, ioaddr + PTP_TCR);
+
+	/* wait for present addend update to complete */
+	limit = 10;
+	while (limit--) {
+		if (!(readl(ioaddr + PTP_TCR) & PTP_TCR_TSADDREG))
+			break;
+		mdelay(10);
+	}
+	if (limit < 0)
+		return -EBUSY;
+
+	return 0;
+}
+
+static int adjust_systime(void __iomem *ioaddr, u32 sec, u32 nsec,
+		int add_sub, int gmac4)
+{
+	u32 value;
+	int limit;
+
+	if (add_sub) {
+		/* If the new sec value needs to be subtracted with
+		 * the system time, then MAC_STSUR reg should be
+		 * programmed with (2^32 – <new_sec_value>)
+		 */
+		if (gmac4)
+			sec = -sec;
+
+		value = readl(ioaddr + PTP_TCR);
+		if (value & PTP_TCR_TSCTRLSSR)
+			nsec = (PTP_DIGITAL_ROLLOVER_MODE - nsec);
+		else
+			nsec = (PTP_BINARY_ROLLOVER_MODE - nsec);
+	}
+
+	writel(sec, ioaddr + PTP_STSUR);
+	value = (add_sub << PTP_STNSUR_ADDSUB_SHIFT) | nsec;
+	writel(value, ioaddr + PTP_STNSUR);
+
+	/* issue command to initialize the system time value */
+	value = readl(ioaddr + PTP_TCR);
+	value |= PTP_TCR_TSUPDT;
+	writel(value, ioaddr + PTP_TCR);
+
+	/* wait for present system time adjust/update to complete */
+	limit = 10;
+	while (limit--) {
+		if (!(readl(ioaddr + PTP_TCR) & PTP_TCR_TSUPDT))
+			break;
+		mdelay(10);
+	}
+	if (limit < 0)
+		return -EBUSY;
+
+	return 0;
+}
+
+static void get_systime(void __iomem *ioaddr, u64 *systime)
+{
+	u64 ns, sec0, sec1;
+
+	/* Get the TSS value */
+	sec1 = readl_relaxed(ioaddr + PTP_STSR);
+	do {
+		sec0 = sec1;
+		/* Get the TSSS value */
+		ns = readl_relaxed(ioaddr + PTP_STNSR);
+		/* Get the TSS value */
+		sec1 = readl_relaxed(ioaddr + PTP_STSR);
+	} while (sec0 != sec1);
+
+	if (systime)
+		*systime = ns + (sec1 * 1000000000ULL);
+}
+
+static void get_ptptime(void __iomem *ptpaddr, u64 *ptp_time)
+{
+	u64 ns;
+
+	ns = readl(ptpaddr + PTP_ATNR);
+	ns += readl(ptpaddr + PTP_ATSR) * NSEC_PER_SEC;
+
+	*ptp_time = ns;
+}
+
+static void timestamp_interrupt(struct stmmac_priv *priv)
+{
+	u32 num_snapshot, ts_status, tsync_int;
+	struct ptp_clock_event event;
+	unsigned long flags;
+	u64 ptp_time;
+	int i;
+
+	if (priv->plat->int_snapshot_en) {
+		wake_up(&priv->tstamp_busy_wait);
+		return;
+	}
+
+	tsync_int = readl(priv->ioaddr + GMAC_INT_STATUS) & GMAC_INT_TSIE;
+
+	if (!tsync_int)
+		return;
+
+	/* Read timestamp status to clear interrupt from either external
+	 * timestamp or start/end of PPS.
+	 */
+	ts_status = readl(priv->ioaddr + GMAC_TIMESTAMP_STATUS);
+
+	if (!priv->plat->ext_snapshot_en)
+		return;
+
+	num_snapshot = (ts_status & GMAC_TIMESTAMP_ATSNS_MASK) >>
+		       GMAC_TIMESTAMP_ATSNS_SHIFT;
+
+	for (i = 0; i < num_snapshot; i++) {
+		read_lock_irqsave(&priv->ptp_lock, flags);
+		get_ptptime(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);
+	}
+}
+
+const struct stmmac_hwtimestamp stmmac_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 = get_ptptime,
+	.timestamp_interrupt = timestamp_interrupt,
+};