sun50i: clean up serial (debug) driver

The serial debug driver is hard to read. Also it uses a C struct
to describe a fixed hardware device' register layout.
Clean up the code to be more readable and switch to the usual
(BASE_ADDR + REG_OFFSET) scheme for accessing registers.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>

2 files changed, 60 insertions, 73 deletions

diff --git a/plat/sun50iw1p1/drivers/uart/uart.c b/plat/sun50iw1p1/drivers/uart/uart.c
index 710957c..bd1e7ff 100644
--- a/plat/sun50iw1p1/drivers/uart/uart.c
+++ b/plat/sun50iw1p1/drivers/uart/uart.c
@@ -33,100 +33,90 @@
 #include <uart.h>
 #include <gpio.h>
 #include <ccmu.h>
+
 #if DEBUG
-#define thr rbr
-#define dll rbr
-#define dlh ier
-#define iir fcr
-
-static serial_hw_t *serial_ctrl_base = NULL;
-static uint32_t uart_lock = 1;
-#if 0
-normal_gpio_set_t uart_ctrl[2] =
-{
-	{ 2, 8, 4, 1, 1, 0, {0}},//PB8: 4--RX
-	{ 2, 9, 4, 1, 1, 0, {0}},//PB9: 4--TX
-};
-#endif
 
-void sunxi_serial_init(int uart_port, void *gpio_cfg, int gpio_max)
+uintptr_t serial_ctrl_base;
+int uart_locked = 1;
+
+void sunxi_serial_init(int uart_port)
 {
-	uint32_t reg, i;
+	uint32_t reg;
 	uint32_t uart_clk;
 
-	if( (uart_port < 0) ||(uart_port > 0) )
-	{
-		return ;
-	}
-	//reset
+	/* assert the UART port's reset line */
 	reg = mmio_read_32(CCMU_BUS_SOFT_RST_REG4);
-	reg &= ~(1<<(CCM_UART_PORT_OFFSET + uart_port));
-	mmio_write_32(CCMU_BUS_SOFT_RST_REG4,reg);
-	for( i = 0; i < 100; i++ );
-	reg |=  (1<<(CCM_UART_PORT_OFFSET + uart_port));
-	mmio_write_32(CCMU_BUS_SOFT_RST_REG4,reg);
-	//gate
+	reg &= ~(1 << (CCM_UART_PORT_OFFSET + uart_port));
+	mmio_write_32(CCMU_BUS_SOFT_RST_REG4, reg);
+
+	/* release the clock gate */
 	reg = mmio_read_32(CCMU_BUS_CLK_GATING_REG3);
-	reg &= ~(1<<(CCM_UART_PORT_OFFSET + uart_port));
-	mmio_write_32(CCMU_BUS_CLK_GATING_REG3,reg);
-	for( i = 0; i < 100; i++ );
-	reg |=  (1<<(CCM_UART_PORT_OFFSET + uart_port));
-	mmio_write_32(CCMU_BUS_CLK_GATING_REG3,reg);
-
-	//gpio
-	//boot_set_gpio(gpio_cfg, gpio_max, 1);  //boot set,so not need to set again
-	//uart init
-	serial_ctrl_base = (serial_hw_t *)(SUNXI_UART0_BASE + uart_port * CCM_UART_ADDR_OFFSET);
-	serial_ctrl_base->mcr = 0x3;
-	uart_clk = (24000000 + 8 * UART_BAUD)/(16 * UART_BAUD);
-	serial_ctrl_base->lcr |= 0x80;
-	serial_ctrl_base->dlh = uart_clk>>8;
-	serial_ctrl_base->dll = uart_clk&0xff;
-	serial_ctrl_base->lcr &= ~0x80;
-	serial_ctrl_base->lcr = ((PARITY&0x03)<<3) | ((STOP&0x01)<<2) | (DLEN&0x03);
-	serial_ctrl_base->fcr = 0x7;
+	reg |=  (1 << (CCM_UART_PORT_OFFSET + uart_port));
+	mmio_write_32(CCMU_BUS_CLK_GATING_REG3, reg);
+
+	/* de-assert the UART port's reset line */
+	reg = mmio_read_32(CCMU_BUS_SOFT_RST_REG4);
+	reg |=  (1 << (CCM_UART_PORT_OFFSET + uart_port));
+	mmio_write_32(CCMU_BUS_SOFT_RST_REG4, reg);
+
+
+	/* The GPIO pins are already configured */
+	serial_ctrl_base = SUNXI_UART0_BASE + uart_port * CCM_UART_ADDR_OFFSET;
+
+	mmio_write_32(serial_ctrl_base + DW_UART_MCR, 0x3);
+	uart_clk = (24000000 + 8 * UART_BAUD) / (16 * UART_BAUD);
+	mmio_write_32(serial_ctrl_base + DW_UART_LCR,
+		      mmio_read_32(serial_ctrl_base + DW_UART_LCR) | 0x80);
+
+	mmio_write_32(serial_ctrl_base + DW_UART_DLH, uart_clk >> 8);
+	mmio_write_32(serial_ctrl_base + DW_UART_DLL, uart_clk & 0xff);
+	mmio_write_32(serial_ctrl_base + DW_UART_LCR,
+		      mmio_read_32(serial_ctrl_base + DW_UART_LCR) & ~0x80);
+	mmio_write_32(serial_ctrl_base + DW_UART_LCR,
+		      (PARITY << 3) | (STOP << 2) | DLEN);
+	mmio_write_32(serial_ctrl_base + DW_UART_FCR, 0x7);
  
-	uart_lock = 0;
+	uart_locked = 0;
 
 	return;
 }
 
-
 void sunxi_serial_exit(void)
 {
-	uart_lock = 1;
+	uart_locked = 1;
 }
 
 void sunxi_serial_putc (char c)
 {
-	if (uart_lock)
+	if (uart_locked)
 		return;
 
-	while((serial_ctrl_base->lsr & ( 1 << 6 )) == 0);
-	serial_ctrl_base->thr = c;
+	while (!(mmio_read_32(serial_ctrl_base + DW_UART_LSR) & 0x40))
+		;
+	mmio_write_32(serial_ctrl_base + DW_UART_THR, c);
 }
 
 
 char sunxi_serial_getc (void)
 {
-	if (uart_lock)
+	if (uart_locked)
 		return 0;
 
-	while((serial_ctrl_base->lsr & 1) == 0);
-	return serial_ctrl_base->rbr;
-
+	while (!(mmio_read_32(serial_ctrl_base + DW_UART_LSR) & 0x01))
+		;
+	return mmio_read_32(serial_ctrl_base + DW_UART_RBR);
 }
 
 int sunxi_serial_tstc (void)
 {
-	return serial_ctrl_base->lsr & 1;
+	return mmio_read_32(serial_ctrl_base + DW_UART_LSR) & 0x01;
 }
 #endif /* DEBUG */
 
 int console_init(unsigned long base_addr,
 		unsigned int uart_clk, unsigned int baud_rate)
 {
-	sunxi_serial_init(0,NULL,0);
+	sunxi_serial_init(0);
 	return 0;
 }
 
@@ -146,4 +136,3 @@ int console_getc(void)
 {
 	return sunxi_serial_getc();
 }
-
diff --git a/plat/sun50iw1p1/include/uart.h b/plat/sun50iw1p1/include/uart.h
index af26c0b..e057bab 100644
--- a/plat/sun50iw1p1/include/uart.h
+++ b/plat/sun50iw1p1/include/uart.h
@@ -1,22 +1,20 @@
 #ifndef _UART_H_
 #define _UART_H_
 
-#define NULL ((void*)0)
 #define CCM_UART_PORT_OFFSET          16
 #define CCM_UART_ADDR_OFFSET          0x400
 
-typedef struct serial_hw
-{
-	volatile unsigned int rbr;		/* 0 */
-	volatile unsigned int ier;		/* 1 */
-	volatile unsigned int fcr;		/* 2 */
-	volatile unsigned int lcr;		/* 3 */
-	volatile unsigned int mcr;		/* 4 */
-	volatile unsigned int lsr;		/* 5 */
-	volatile unsigned int msr;		/* 6 */
-	volatile unsigned int sch;		/* 7 */
-}serial_hw_t;
-
+#define DW_UART_RBR	0x00
+#define DW_UART_THR	0x00
+#define DW_UART_DLL	0x00
+#define DW_UART_IER	0x04
+#define DW_UART_DLH	0x04
+#define DW_UART_FCR	0x08
+#define DW_UART_LCR	0x0c
+#define DW_UART_MCR	0x10
+#define DW_UART_LSR	0x14
+#define DW_UART_MSR	0x18
+#define DW_UART_SCH	0x1c
 
 #define   UART_BAUD    115200      // Baud rate for UART
                                    // Compute the divisor factor
@@ -26,13 +24,13 @@ typedef struct serial_hw
 #define   DLEN         3           // Data Length: 0 - 5bits; 1 - 6bits; 2 - 7bits; 3 - 8bits
 
 #if DEBUG
-void sunxi_serial_init(int uart_port, void *gpio_cfg, int gpio_max);
+void sunxi_serial_init(int uart_port);
 void sunxi_serial_exit(void);
 void sunxi_serial_putc (char c);
 char sunxi_serial_getc (void);
 int sunxi_serial_tstc (void);
 #else
-static inline void sunxi_serial_init(int uart_port, void *gpio_cfg, int gpio_max) {}
+static inline void sunxi_serial_init(int uart_port) {}
 static inline void sunxi_serial_exit(void) {}
 static inline void sunxi_serial_putc(char c) {}
 static inline char sunxi_serial_getc(void) { return 0;}