blackfin: Set correct early debug serial baudrate.

Calculate the early uart clock from the system clock registers set by
the bootrom other than the predefine uboot clock macros.

Split the early baudrate setting function and the normal baudrate
setting one.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
diff --git a/arch/blackfin/cpu/serial4.h b/arch/blackfin/cpu/serial4.h
index 887845c..6548396 100644
--- a/arch/blackfin/cpu/serial4.h
+++ b/arch/blackfin/cpu/serial4.h
@@ -15,6 +15,8 @@
 
 #ifndef __ASSEMBLY__
 
+#include <asm/clock.h>
+
 #define MMR_UART(n) _PASTE_UART(n, UART, REVID)
 #define UART_BASE MMR_UART(CONFIG_UART_CONSOLE)
 
@@ -84,20 +86,6 @@
 }
 
 __attribute__((always_inline))
-static inline uint32_t uart_sclk(void)
-{
-#if defined(BFIN_IN_INITCODE) || defined(CONFIG_DEBUG_EARLY_SERIAL)
-	/* We cannot use get_sclk() early on as it uses caches in
-	 * external memory
-	 */
-	return CONFIG_CLKIN_HZ * CONFIG_VCO_MULT / CONFIG_SCLK_DIV /
-		CONFIG_SCLK0_DIV;
-#else
-	return get_sclk0();
-#endif
-}
-
-__attribute__((always_inline))
 static inline int uart_init(uint32_t uart_base)
 {
 	/* always enable UART to 8-bit mode */
@@ -127,19 +115,20 @@
 }
 
 __attribute__((always_inline))
-static inline int serial_early_enabled(uint32_t uart_base)
+static inline void serial_set_divisor(uint32_t uart_base, uint16_t divisor)
 {
-	return bfin_read(&pUART->control) & UEN;
+	/* Program the divisor to get the baud rate we want */
+	bfin_write(&pUART->clock, divisor);
+	SSYNC();
 }
 
 __attribute__((always_inline))
 static inline void serial_early_set_baud(uint32_t uart_base, uint32_t baud)
 {
-	uint32_t divisor = uart_sclk() / (baud * 16);
+	uint16_t divisor = early_division(early_get_uart_clk(), baud * 16);
 
 	/* Program the divisor to get the baud rate we want */
-	bfin_write(&pUART->clock, divisor);
-	SSYNC();
+	serial_set_divisor(uart_base, divisor);
 }
 
 __attribute__((always_inline))