/*
 * Copyright 2004-2008, Axel Dörfler, axeld@pinc-software.de.
 * Distributed under the terms of the MIT License.
 *
 * Copyright 2012-2015, Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *              Axel Dörfler, axeld@pinc-software.de
 *              Alexander von Gluck IV, kallisti5@unixzen.com
 */


#include "serial.h"

#include <arch/generic/debug_uart_8250.h>

#if defined(__arm__)
#include <arch/arm/arch_uart_pl011.h>
#endif

#include <boot/platform.h>
#include <arch/cpu.h>
#include <boot/stage2.h>
#include <new>
#include <string.h>

extern "C" {
#include <fdt.h>
#include <libfdt.h>
#include <libfdt_env.h>
};

#include "fdt_serial.h"


DebugUART* gUART;

static int32 sSerialEnabled = 0;
static char sBuffer[16384];
static uint32 sBufferPosition;


static void
serial_putc(char c)
{
        if (gUART == NULL || sSerialEnabled <= 0)
                return;

        gUART->PutChar(c);
}


extern "C" int
serial_getc(bool wait)
{
        if (gUART == NULL || sSerialEnabled <= 0)
                return 0;

        return gUART->GetChar(wait);
}


extern "C" void
serial_puts(const char* string, size_t size)
{
        if (sSerialEnabled <= 0)
                return;

        if (sBufferPosition + size < sizeof(sBuffer)) {
                memcpy(sBuffer + sBufferPosition, string, size);
                sBufferPosition += size;
        }

        while (size-- != 0) {
                char c = string[0];

                if (c == '\n') {
                        serial_putc('\r');
                        serial_putc('\n');
                } else if (c != '\r')
                        serial_putc(c);

                string++;
        }
}


extern "C" void
serial_disable(void)
{
        sSerialEnabled = 0;
}


extern "C" void
serial_enable(void)
{
        /* should already be initialized by U-Boot */
        gUART->InitEarly();
        gUART->InitPort(115200);
        sSerialEnabled++;
}


extern "C" void
serial_cleanup(void)
{
        if (sSerialEnabled <= 0)
                return;

        gKernelArgs.debug_output = kernel_args_malloc(sBufferPosition);
        if (gKernelArgs.debug_output != NULL) {
                memcpy(gKernelArgs.debug_output, sBuffer, sBufferPosition);
                gKernelArgs.debug_size = sBufferPosition;
        }
}


extern "C" void
serial_init(const void *fdt)
{
        // first try with hints from the FDT
        gUART = debug_uart_from_fdt(fdt);

        // Do we can some kind of direct fallback here
        // (aka, guess arch_get_uart_pl011 or arch_get_uart_8250?)
        if (gUART == NULL)
                return;

        serial_enable();
}