niagara.c

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/*
 * Copyright (c) 2006 Ondrej Palkovsky
 * Copyright (c) 2008 Martin Decky
 * Copyright (c) 2008 Pavel Rimsky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <async.h>
#include <sysinfo.h>
#include <as.h>
#include <errno.h>
#include <stdio.h>
#include <ddi.h>

#include "serial_console.h"
#include "niagara.h"

#define WIDTH 80
#define HEIGHT 24

static uintptr_t output_buffer_addr;

/*
 * Kernel counterpart of the driver reads characters to be printed from here.
 * Keep in sync with the definition from
 * kernel/arch/sparc64/src/drivers/niagara.c.
 */
#define OUTPUT_BUFFER_SIZE      ((PAGE_SIZE) - 2 * 8)
typedef volatile struct {
        uint64_t read_ptr;
        uint64_t write_ptr;
        char data[OUTPUT_BUFFER_SIZE];
}
        __attribute__ ((packed))
        __attribute__ ((aligned(PAGE_SIZE)))
        *output_buffer_t;

output_buffer_t output_buffer;

static void niagara_putc(char c)
{
        while (output_buffer->write_ptr ==
               (output_buffer->read_ptr + OUTPUT_BUFFER_SIZE - 1)
               % OUTPUT_BUFFER_SIZE)
                ;
        output_buffer->data[output_buffer->write_ptr] = (uint64_t) c;
        output_buffer->write_ptr =
                ((output_buffer->write_ptr) + 1) % OUTPUT_BUFFER_SIZE;
}

int niagara_init(void)
{
        sysarg_t paddr;
        if (sysinfo_get_value("niagara.outbuf.address", &paddr) != EOK)
                return -1;
        
        output_buffer_addr = (uintptr_t) as_get_mappable_page(PAGE_SIZE);
        int result = physmem_map((void *) paddr,
            (void *) output_buffer_addr, 1,
            AS_AREA_READ | AS_AREA_WRITE);

        if (result != 0) {
                printf("Niagara: uspace driver couldn't map physical memory: %d\n",
                        result);
        }

        output_buffer = (output_buffer_t) output_buffer_addr;

        serial_console_init(niagara_putc, WIDTH, HEIGHT);
        async_set_client_connection(serial_client_connection);
        return 0;
}

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