clk: Add axi-clkgen driver

This driver adds support for the AXI clkgen pcore to the common clock framework.
The AXI clkgen pcore is a AXI front-end to the MMCM_ADV frequency synthesizer
commonly found in Xilinx FPGAs.

The AXI clkgen pcore is used in Analog Devices' reference designs targeting
Xilinx FPGAs.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index a47e6ee..a64caef 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -63,6 +63,14 @@
 	  McPDM. McPDM module is using the external bit clock on the McPDM bus
 	  as functional clock.
 
+config COMMON_CLK_AXI_CLKGEN
+	tristate "AXI clkgen driver"
+	depends on ARCH_ZYNQ || MICROBLAZE
+	help
+	---help---
+	  Support for the Analog Devices axi-clkgen pcore clock generator for Xilinx
+	  FPGAs. It is commonly used in Analog Devices' reference designs.
+
 endmenu
 
 source "drivers/clk/mvebu/Kconfig"