arm: zynq: Migrate platform to clock controller

Migrate the Zynq platform and its drivers to use the new clock
controller driver.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clocksource/cadence_ttc_timer.c b/drivers/clocksource/cadence_ttc_timer.c
index 685bc60..4cbe28c 100644
--- a/drivers/clocksource/cadence_ttc_timer.c
+++ b/drivers/clocksource/cadence_ttc_timer.c
@@ -51,6 +51,8 @@
 
 #define TTC_CNT_CNTRL_DISABLE_MASK	0x1
 
+#define TTC_CLK_CNTRL_CSRC_MASK		(1 << 5)	/* clock source */
+
 /*
  * Setup the timers to use pre-scaling, using a fixed value for now that will
  * work across most input frequency, but it may need to be more dynamic
@@ -396,8 +398,9 @@
 {
 	unsigned int irq;
 	void __iomem *timer_baseaddr;
-	struct clk *clk;
+	struct clk *clk_cs, *clk_ce;
 	static int initialized;
+	int clksel;
 
 	if (initialized)
 		return;
@@ -421,14 +424,24 @@
 		BUG();
 	}
 
-	clk = of_clk_get_by_name(timer, "cpu_1x");
-	if (IS_ERR(clk)) {
+	clksel = __raw_readl(timer_baseaddr + TTC_CLK_CNTRL_OFFSET);
+	clksel = !!(clksel & TTC_CLK_CNTRL_CSRC_MASK);
+	clk_cs = of_clk_get(timer, clksel);
+	if (IS_ERR(clk_cs)) {
 		pr_err("ERROR: timer input clock not found\n");
 		BUG();
 	}
 
-	ttc_setup_clocksource(clk, timer_baseaddr);
-	ttc_setup_clockevent(clk, timer_baseaddr + 4, irq);
+	clksel = __raw_readl(timer_baseaddr + 4 + TTC_CLK_CNTRL_OFFSET);
+	clksel = !!(clksel & TTC_CLK_CNTRL_CSRC_MASK);
+	clk_ce = of_clk_get(timer, clksel);
+	if (IS_ERR(clk_ce)) {
+		pr_err("ERROR: timer input clock not found\n");
+		BUG();
+	}
+
+	ttc_setup_clocksource(clk_cs, timer_baseaddr);
+	ttc_setup_clockevent(clk_ce, timer_baseaddr + 4, irq);
 
 	pr_info("%s #0 at %p, irq=%d\n", timer->name, timer_baseaddr, irq);
 }