/*
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 * and open the template in the editor.
 */

#include <stddef.h>
#include "board.h"
#include "../../regdef.h"

extern uart_if_t uart_if[];

#define ARRAYSIZE(a)	(sizeof(a)/sizeof(a[0]))

const con_if_entry_t con_if_entry[] =
{
	{0, "stdin", &uart_if[0], NULL, NULL, UART_readchar, NULL},
	{1, "stdout", &uart_if[0], NULL, NULL, NULL, UART_writechar},
	{2, "stderr", &uart_if[0], NULL, NULL, NULL, UART_writechar},
	{3, "UART-0", &uart_if[0], NULL, NULL, UART_readchar, UART_writechar},
	{4, "UART-1", &uart_if[1], NULL, NULL, UART_readchar, UART_writechar}
};

con_if_t con_if =
{
	con_if_entry, ARRAYSIZE(con_if_entry)
};

static uart_if_t const *dbg_uart = NULL;
static volatile uint32_t *pGpioData = (uint32_t*)SYS_GPIO_0_DATA;
static volatile uint32_t *pGpioDir = (uint32_t*)SYS_GPIO_0_DIR;
static uint32_t led_count = 0;

extern int dbg_handler(struct xcptcontext * xcp);
extern void handle_exception (unsigned long *registers);

int gdb_stub(struct xcptcontext * xcp)
{
	handle_exception((unsigned long *)xcp);
	return 0;
}

void dbg_uart_isr(struct xcptcontext *xcp)
{
	if(SYS_UART_BIT_RX_AVAIL & *dbg_uart->pCTRL)
	{
		char c = *dbg_uart->pDATA;
		if (c == 3)
		{
			gdb_stub(xcp);
		}
	}
}

void dbg_uart_setup()
{
	const int UART_INT = SYS_INT_UART1;
	dbg_uart = (uart_if_t*)con_getInterfaceByName("UART-1")->pInst;
	
	*dbg_uart->pCTRL = SYS_UART_BIT_RX_INTEN;
	interrupt_register(UART_INT, dbg_uart_isr);
	interrupt_enable(UART_INT);
}

inline void _dbg_writechar(uart_if_t const *pUart, char c)
{
	while((SYS_UART_BIT_TX_HALFFULL & *pUart->pCTRL) != 0);

	*pUart->pDATA = (uint32_t)c;
	
}

inline char _dbg_readchar(uart_if_t const *pUart)
{
	// busy read
	while(!(SYS_UART_BIT_RX_AVAIL & *pUart->pCTRL))
	{
		(*pGpioData) = (led_count++) >> 16;
	}
	led_count = 0;
	return (*pUart->pDATA & 0xFF);

}

void dbg_putchar(char c)
{
	if (c == 0x0A)
	{
		_dbg_writechar(dbg_uart, 0x0D);
	}
	_dbg_writechar(dbg_uart, c);
}

char dbg_getchar()
{
	return (char)_dbg_readchar(dbg_uart);
}

void dbg_init()
{
	xcpt_register(EXC_BP, gdb_stub);
}

void board_init(void)
{
	uint32_t volatile *pITIM_ctrl = (uint32_t*)SYS_ITIM_CTRL;

	// Disable timers
	*pITIM_ctrl = 0;

	// Setup syscall support
	syscalls_init();

	// Setup Uart ISR 
	dbg_uart_setup();

	// Setup debugger
	dbg_init();

	// Setup interrupt support
	interrupt_init();

	// Do some initializations here
	*pGpioDir = 0xFF;
}