[PATCH v3 7/7] drivers: net: macb: add fu740 support

[Green Wan]

From: David Abdurachmanov <david.abdurachmanov at sifive.com>

Add fu740 support to macb ethernet driver

There is a PLL HW quirk in FU740. The VSC8541XMV-02 specification
requires 125 +/-0.0125 Mhz. But the most close value can be output
by PLL is 125.125 MHz and out of VSC8541XMV-02 spec.

Signed-off-by: David Abdurachmanov <david.abdurachmanov at sifive.com>
Signed-off-by: Green Wan <green.wan at sifive.com>
Reviewed-by: Ramon Fried <rfried.dev at gmail.com>
---
 drivers/net/macb.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/net/macb.c b/drivers/net/macb.c
index 57ea45e2dc..bf70525c54 100644
--- a/drivers/net/macb.c
+++ b/drivers/net/macb.c
@@ -591,8 +591,17 @@ static int macb_sifive_clk_init(struct udevice *dev, ulong rate)
 	 * 0 = GMII mode. Use 125 MHz gemgxlclk from PRCI in TX logic
 	 *     and output clock on GMII output signal GTX_CLK
 	 * 1 = MII mode. Use MII input signal TX_CLK in TX logic
+	 *
+	 * FU740 have a PLL HW quirk. The 125.125 Mhz is actually out of
+	 * VSC8541XMV-02 specification. The tolerance level is +/-100ppm.
+	 * Which means the range should be in between 125MHz +/-0.0125.
+	 * But the most close value can be output by PLL is 125.125 MHz.
 	 */
-	writel(rate != 125000000, gemgxl_regs);
+	if (device_is_compatible(dev, "sifive,fu540-c000-gem"))
+		writel(rate != 125000000, gemgxl_regs);
+	else if (device_is_compatible(dev, "sifive,fu740-c000-gem"))
+		writel(rate != 125125000, gemgxl_regs);
+
 	return 0;
 }
 
@@ -1507,6 +1516,8 @@ static const struct udevice_id macb_eth_ids[] = {
 	{ .compatible = "cdns,zynq-gem" },
 	{ .compatible = "sifive,fu540-c000-gem",
 	  .data = (ulong)&sifive_config },
+	{ .compatible = "sifive,fu740-c000-gem",
+	  .data = (ulong)&sifive_config },
 	{ .compatible = "microchip,mpfs-mss-gem",
 	  .data = (ulong)&microchip_config },
 	{ }
-- 
2.31.0