arm: mvebu: Add support for NAND interface on A-38x

The NAND interface on the Armada-38x series is similar to that on the
Armada-XP. The key difference is that the NAND ECC clock ratio is
provided via the DFX Server registers instead of the Core Clock.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Cc: Dirk Eibach <eibach@gdsys.de>
Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/arch/arm/mach-mvebu/cpu.c b/arch/arm/mach-mvebu/cpu.c
index fd66f59..5eb2a39 100644
--- a/arch/arm/mach-mvebu/cpu.c
+++ b/arch/arm/mach-mvebu/cpu.c
@@ -452,8 +452,15 @@
 
 u32 mvebu_get_nand_clock(void)
 {
+	u32 reg;
+
+	if (mvebu_soc_family() == MVEBU_SOC_A38X)
+		reg = MVEBU_DFX_DIV_CLK_CTRL(1);
+	else
+		reg = MVEBU_CORE_DIV_CLK_CTRL(1);
+
 	return CONFIG_SYS_MVEBU_PLL_CLOCK /
-		((readl(MVEBU_CORE_DIV_CLK_CTRL(1)) &
+		((readl(reg) &
 		  NAND_ECC_DIVCKL_RATIO_MASK) >> NAND_ECC_DIVCKL_RATIO_OFFS);
 }