net: stmmac: Add PTP support for XGMAC2

XGMAC2 uses the same engine of timestamping as GMAC4. Let's use the same
callbacks.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/hwif.c

@@ -193,13 +193,13 @@ static const struct stmmac_hwif_entry {
 		.xgmac = true,
 		.min_id = DWXGMAC_CORE_2_10,
 		.regs = {
-			.ptp_off = 0,
+			.ptp_off = PTP_XGMAC_OFFSET,
 			.mmc_off = 0,
 		},
 		.desc = &dwxgmac210_desc_ops,
 		.dma = &dwxgmac210_dma_ops,
 		.mac = &dwxgmac210_ops,
-		.hwtimestamp = NULL,
+		.hwtimestamp = &stmmac_ptp,
 		.mode = NULL,
 		.tc = NULL,
 		.setup = dwxgmac2_setup,

drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c

@@ -71,6 +71,9 @@ static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
 	u32 sec, nsec;
 	u32 quotient, reminder;
 	int neg_adj = 0;
+	bool xmac;
+
+	xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;
 
 	if (delta < 0) {
 		neg_adj = 1;
@@ -82,8 +85,7 @@ static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
 	nsec = reminder;
 
 	spin_lock_irqsave(&priv->ptp_lock, flags);
-	stmmac_adjust_systime(priv, priv->ptpaddr, sec, nsec, neg_adj,
-			priv->plat->has_gmac4);
+	stmmac_adjust_systime(priv, priv->ptpaddr, sec, nsec, neg_adj, xmac);
 	spin_unlock_irqrestore(&priv->ptp_lock, flags);
 
 	return 0;

drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h

@@ -21,6 +21,7 @@
 #ifndef	__STMMAC_PTP_H__
 #define	__STMMAC_PTP_H__
 
+#define PTP_XGMAC_OFFSET	0xd00
 #define	PTP_GMAC4_OFFSET	0xb00
 #define	PTP_GMAC3_X_OFFSET	0x700