[PATCH 6/9] ravb: Use separate clock for gPTP

[Phil Edworthy <phil.edworthy@xxxxxxxxxxx>]

RZ/V2M has a separate gPTP reference clock that is used when the
AVB-DMAC Mode Register (CCC) gPTP Clock Select (CSEL) bits are
set to "01: High-speed peripheral bus clock".
Therefore, add a feature that allows this clock to be used for
gPTP.

Signed-off-by: Phil Edworthy <phil.edworthy@xxxxxxxxxxx>
Reviewed-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
 drivers/net/ethernet/renesas/ravb.h      |  2 ++
 drivers/net/ethernet/renesas/ravb_main.c | 15 ++++++++++++++-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index 73976a392457..f8706897ea41 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -1032,6 +1032,7 @@ struct ravb_hw_info {
 	unsigned gptp:1;		/* AVB-DMAC has gPTP support */
 	unsigned ccc_gac:1;		/* AVB-DMAC has gPTP support active in config mode */
 	unsigned gptp_ptm_gic:1;	/* gPTP enables Presentation Time Match irq via GIC */
+	unsigned gptp_ref_clk:1;	/* gPTP has separate reference clock */
 	unsigned nc_queues:1;		/* AVB-DMAC has RX and TX NC queues */
 	unsigned magic_pkt:1;		/* E-MAC supports magic packet detection */
 	unsigned half_duplex:1;		/* E-MAC supports half duplex mode */
@@ -1043,6 +1044,7 @@ struct ravb_private {
 	void __iomem *addr;
 	struct clk *clk;
 	struct clk *refclk;
+	struct clk *gptp_clk;
 	struct mdiobb_ctrl mdiobb;
 	u32 num_rx_ring[NUM_RX_QUEUE];
 	u32 num_tx_ring[NUM_TX_QUEUE];
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index f12a23b9c391..ded87cb51650 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2496,11 +2496,15 @@ MODULE_DEVICE_TABLE(of, ravb_match_table);
 static int ravb_set_gti(struct net_device *ndev)
 {
 	struct ravb_private *priv = netdev_priv(ndev);
+	const struct ravb_hw_info *info = priv->info;
 	struct device *dev = ndev->dev.parent;
 	unsigned long rate;
 	uint64_t inc;
 
-	rate = clk_get_rate(priv->clk);
+	if (info->gptp_ref_clk)
+		rate = clk_get_rate(priv->gptp_clk);
+	else
+		rate = clk_get_rate(priv->clk);
 	if (!rate)
 		return -EINVAL;
 
@@ -2715,6 +2719,15 @@ static int ravb_probe(struct platform_device *pdev)
 	}
 	clk_prepare_enable(priv->refclk);
 
+	if (info->gptp_ref_clk) {
+		priv->gptp_clk = devm_clk_get(&pdev->dev, "gptp");
+		if (IS_ERR(priv->gptp_clk)) {
+			error = PTR_ERR(priv->gptp_clk);
+			goto out_release;
+		}
+		clk_prepare_enable(priv->gptp_clk);
+	}
+
 	ndev->max_mtu = info->rx_max_buf_size - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN);
 	ndev->min_mtu = ETH_MIN_MTU;
 
-- 
2.32.0