ARCv3:haps: Set core and UART clock frequency to 20MHz

All recent bitfiles are built for 20MHz core clock.

Signed-off-by: Pavel Kozlov <pavel.kozlov@synopsys.com>

Author: pavelvkozlov

arch/arc/boot/dts/haps_hs.dts

@@ -40,7 +40,7 @@
 		core_clk: core_clk {
 			#clock-cells = <0>;
 			compatible = "fixed-clock";
-			clock-frequency = <50000000>;
+			clock-frequency = <20000000>;
 		};
 
 		core_intc: interrupt-controller {
@@ -53,7 +53,7 @@
 			compatible = "ns16550a";
 			reg = <0xf0000000 0x2000>;
 			interrupts = <24>;
-			clock-frequency = <50000000>;
+			clock-frequency = <20000000>;
 			baud = <115200>;
 			reg-shift = <2>;
 			reg-io-width = <4>;

arch/arc/boot/dts/haps_hs_idu.dts

@@ -37,7 +37,7 @@
 		core_clk: core_clk {
 			#clock-cells = <0>;
 			compatible = "fixed-clock";
-			clock-frequency = <50000000>;	/* 50 MHZ */
+			clock-frequency = <20000000>;	/* 20 MHZ */
 		};
 
 		core_intc: interrupt-controller {
@@ -58,7 +58,7 @@
 			reg = <0xf0000000 0x2000>;
 			interrupt-parent = <&idu_intc>;
 			interrupts = <0>;
-			clock-frequency = <50000000>;
+			clock-frequency = <20000000>;
 			baud = <115200>;
 			reg-shift = <2>;
 			reg-io-width = <4>;

arch/arc/kernel/devtree.c

@@ -18,7 +18,7 @@
 static unsigned int __initdata arc_base_baud;
 
 //These two variables exist only for debugging perposes
-volatile unsigned int glb_clock_freq = 50000000;
+volatile unsigned int glb_clock_freq = 20000000;
 volatile unsigned int glb_uart_baud = 115200;
 
 unsigned int __init arc_early_base_baud(void)