clk: davinci: New driver for davinci PLL clocks

This adds a new driver for mach-davinci PLL clocks. This is porting the
code from arch/arm/mach-davinci/clock.c to the common clock framework.
Additionally, it adds device tree support for these clocks.

The ifeq ($(CONFIG_COMMON_CLK), y) in the Makefile is needed to prevent
compile errors until the clock code in arch/arm/mach-davinci is removed.

Note: although there are similar clocks for TI Keystone we are not able
to share the code for a few reasons. The keystone clocks are device tree
only and use legacy one-node-per-clock bindings. Also the register
layouts are a bit different, which would add even more if/else mess
to the keystone clocks. And the keystone PLL driver doesn't support
setting clock rates.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

MAINTAINERS

@@ -13792,6 +13792,13 @@ F:	arch/arm/mach-davinci/
 F:	drivers/i2c/busses/i2c-davinci.c
 F:	arch/arm/boot/dts/da850*
 
+TI DAVINCI SERIES CLOCK DRIVER
+M:	David Lechner <david@lechnology.com>
+R:	Sekhar Nori <nsekhar@ti.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/clock/ti/davinci/
+F:	drivers/clk/davinci/
+
 TI DAVINCI SERIES GPIO DRIVER
 M:	Keerthy <j-keerthy@ti.com>
 L:	linux-gpio@vger.kernel.org

drivers/clk/Makefile

@@ -61,6 +61,7 @@ obj-$(CONFIG_ARCH_ARTPEC)		+= axis/
 obj-$(CONFIG_ARC_PLAT_AXS10X)		+= axs10x/
 obj-y					+= bcm/
 obj-$(CONFIG_ARCH_BERLIN)		+= berlin/
+obj-$(CONFIG_ARCH_DAVINCI)		+= davinci/
 obj-$(CONFIG_H8300)			+= h8300/
 obj-$(CONFIG_ARCH_HISI)			+= hisilicon/
 obj-y					+= imgtec/

drivers/clk/davinci/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+ifeq ($(CONFIG_COMMON_CLK), y)
+obj-y += pll.o
+endif