lpc43xx_hic,uart: replace CGU code with direct register setup

Author: Adrian Negreanu

source/hic_hal/nxp/lpc4322/uart.c

@@ -21,7 +21,6 @@
 
 #include "LPC43xx.h"
 #include "uart.h"
-#include "lpc43xx_cgu.h"
 #include "lpc43xx_scu.h"
 #include "util.h"
 #include "circ_buf.h"
@@ -31,8 +30,6 @@ static uint32_t baudrate;
 static uint32_t dll;
 static uint32_t tx_in_progress;
 
-extern uint32_t SystemCoreClock;
-
 #define RX_OVRF_MSG         "<DAPLink:Overflow>\n"
 #define RX_OVRF_MSG_SIZE    (sizeof(RX_OVRF_MSG) - 1)
 #define  BUFFER_SIZE    (512)
@@ -56,11 +53,18 @@ static int32_t reset(void);
 
 int32_t uart_initialize(void)
 {
+    uint32_t tmp;
     NVIC_DisableIRQ(UART_IRQn);
 
     // The baudrate calculations require the UART to be clocked as SystemCoreClock
-    CGU_EntityConnect(CGU_CLKSRC_PLL1, CGU_BASE_UART0);
-    CGU_EnableEntity(CGU_BASE_UART0, ENABLE);
+    tmp = LPC_CGU->BASE_UART0_CLK & ~(0x0F << 24);  // clear CLK_SEL.
+    LPC_CGU->BASE_UART0_CLK = tmp
+                            | (0x01 << 11)          // AUTOBLOCK: 0=Disabled, 1=Enabled.
+                            | (0x09 << 24)          // CLK_SEL = PLL1.
+                            ;
+
+    LPC_CGU->BASE_UART0_CLK &= ~1; // PD: 0=Power Up.
+
     scu_pinmux(2, 0, UART_RX_TX, FUNC1);   /* P2_0: U0_TXD */
     scu_pinmux(2, 1, UART_RX_TX, FUNC1);   /* P2_1: U0_RXD */