Archipelago » qemu

/*

 * Framebuffer device helper routines

 *

 * Copyright (c) 2009 CodeSourcery

 * Written by Paul Brook <paul@codesourcery.com>

 *

 * This code is licensed under the GNU GPLv2.

 */

/* TODO:

   - Do something similar for framebuffers with local ram

   - Handle rotation here instead of hacking dest_pitch

   - Use common pixel conversion routines instead of per-device drawfn

   - Remove all DisplayState knowledge from devices.

 */

#include "hw.h"

#include "console.h"

#include "framebuffer.h"

#include "kvm.h"

/* Render an image from a shared memory framebuffer.  */

void framebuffer_update_display(

    DisplayState *ds,

    target_phys_addr_t base,

    int cols, /* Width in pixels.  */

    int rows, /* Leight in pixels.  */

    int src_width, /* Length of source line, in bytes.  */

    int dest_row_pitch, /* Bytes between adjacent horizontal output pixels.  */

    int dest_col_pitch, /* Bytes between adjacent vertical output pixels.  */

    int invalidate, /* nonzero to redraw the whole image.  */

    drawfn fn,

    void *opaque,

    int *first_row, /* Input and output.  */

    int *last_row /* Output only */)

{

    target_phys_addr_t src_len;

    uint8_t *dest;

    uint8_t *src;

    uint8_t *src_base;

    int first, last = 0;

    int dirty;

    int i;

    ram_addr_t addr;

    ram_addr_t pd;

    ram_addr_t pd2;

    i = *first_row;

    *first_row = -1;

    src_len = src_width * rows;

    if (kvm_enabled()) {

        kvm_physical_sync_dirty_bitmap(base, src_len);

    }

    pd = cpu_get_physical_page_desc(base);

    pd2 = cpu_get_physical_page_desc(base + src_len - 1);

    /* We should reall check that this is a continuous ram region.

       Instead we just check that the first and last pages are

       both ram, and the right distance apart.  */

    if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM

        || (pd2 & ~TARGET_PAGE_MASK) > IO_MEM_ROM) {

        return;

    }

    pd = (pd & TARGET_PAGE_MASK) + (base & ~TARGET_PAGE_MASK);

    if (((pd + src_len - 1) & TARGET_PAGE_MASK) != (pd2 & TARGET_PAGE_MASK)) {

        return;

    }

    src_base = cpu_physical_memory_map(base, &src_len, 0);

    /* If we can't map the framebuffer then bail.  We could try harder,

       but it's not really worth it as dirty flag tracking will probably

       already have failed above.  */

    if (!src_base)

        return;

    if (src_len != src_width * rows) {

        cpu_physical_memory_unmap(src_base, src_len, 0, 0);

        return;

    }

    src = src_base;

    dest = ds_get_data(ds);

    if (dest_col_pitch < 0)

        dest -= dest_col_pitch * (cols - 1);

    first = -1;

    addr = pd;

    addr += i * src_width;

    src += i * src_width;

    dest += i * dest_row_pitch;

    for (; i < rows; i++) {

        target_phys_addr_t dirty_offset;

        dirty = 0;

        dirty_offset = 0;

        while (addr + dirty_offset < TARGET_PAGE_ALIGN(addr + src_width)) {

            dirty |= cpu_physical_memory_get_dirty(addr + dirty_offset,

                                                   VGA_DIRTY_FLAG);

            dirty_offset += TARGET_PAGE_SIZE;

        }

        if (dirty || invalidate) {

            fn(opaque, dest, src, cols, dest_col_pitch);

            if (first == -1)

                first = i;

            last = i;

        }

        addr += src_width;

        src += src_width;

        dest += dest_row_pitch;

    }

    cpu_physical_memory_unmap(src_base, src_len, 0, 0);

    if (first < 0) {

        return;

    }

    cpu_physical_memory_reset_dirty(pd, pd + src_len, VGA_DIRTY_FLAG);

    *first_row = first;

    *last_row = last;

    return;

}