hw/framebuffer.c

   1 /*
   2  * Framebuffer device helper routines
   3  *
   4  * Copyright (c) 2009 CodeSourcery
   5  * Written by Paul Brook <paul@codesourcery.com>
   6  *
   7  * This code is licensed under the GNU GPLv2.
   8  */
   9
  10 /* TODO:
  11    - Do something similar for framebuffers with local ram
  12    - Handle rotation here instead of hacking dest_pitch
  13    - Use common pixel conversion routines instead of per-device drawfn
  14    - Remove all DisplayState knowledge from devices.
  15  */
  16
  17 #include "hw.h"
  18 #include "console.h"
  19 #include "framebuffer.h"
  20
  21 /* Render an image from a shared memory framebuffer.  */
  22
  23 void framebuffer_update_display(
  24     DisplayState *ds,
  25     target_phys_addr_t base,
  26     int cols, /* Width in pixels.  */
  27     int rows, /* Leight in pixels.  */
  28     int src_width, /* Length of source line, in bytes.  */
  29     int dest_row_pitch, /* Bytes between adjacent horizontal output pixels.  */
  30     int dest_col_pitch, /* Bytes between adjacent vertical output pixels.  */
  31     int invalidate, /* nonzero to redraw the whole image.  */
  32     drawfn fn,
  33     void *opaque,
  34     int *first_row, /* Input and output.  */
  35     int *last_row /* Output only */)
  36 {
  37     target_phys_addr_t src_len;
  38     uint8_t *dest;
  39     uint8_t *src;
  40     uint8_t *src_base;
  41     int first, last = 0;
  42     int dirty;
  43     int i;
  44     ram_addr_t addr;
  45     ram_addr_t pd;
  46     ram_addr_t pd2;
  47
  48     i = *first_row;
  49     *first_row = -1;
  50     src_len = src_width * rows;
  51
  52     cpu_physical_sync_dirty_bitmap(base, base + src_len);
  53     pd = cpu_get_physical_page_desc(base);
  54     pd2 = cpu_get_physical_page_desc(base + src_len - 1);
  55     /* We should reall check that this is a continuous ram region.
  56        Instead we just check that the first and last pages are
  57        both ram, and the right distance apart.  */
  58     if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM
  59         || (pd2 & ~TARGET_PAGE_MASK) > IO_MEM_ROM) {
  60         return;
  61     }
  62     pd = (pd & TARGET_PAGE_MASK) + (base & ~TARGET_PAGE_MASK);
  63     if (((pd + src_len - 1) & TARGET_PAGE_MASK) != (pd2 & TARGET_PAGE_MASK)) {
  64         return;
  65     }
  66
  67     src_base = cpu_physical_memory_map(base, &src_len, 0);
  68     /* If we can't map the framebuffer then bail.  We could try harder,
  69        but it's not really worth it as dirty flag tracking will probably
  70        already have failed above.  */
  71     if (!src_base)
  72         return;
  73     if (src_len != src_width * rows) {
  74         cpu_physical_memory_unmap(src_base, src_len, 0, 0);
  75         return;
  76     }
  77     src = src_base;
  78     dest = ds_get_data(ds);
  79     if (dest_col_pitch < 0)
  80         dest -= dest_col_pitch * (cols - 1);
  81     first = -1;
  82     addr = pd;
  83
  84     addr += i * src_width;
  85     src += i * src_width;
  86     dest += i * dest_row_pitch;
  87
  88     for (; i < rows; i++) {
  89         target_phys_addr_t dirty_offset;
  90         dirty = 0;
  91         dirty_offset = 0;
  92         while (addr + dirty_offset < TARGET_PAGE_ALIGN(addr + src_width)) {
  93             dirty |= cpu_physical_memory_get_dirty(addr + dirty_offset,
  94                                                    VGA_DIRTY_FLAG);
  95             dirty_offset += TARGET_PAGE_SIZE;
  96         }
  97
  98         if (dirty || invalidate) {
  99             fn(opaque, dest, src, cols, dest_col_pitch);
 100             if (first == -1)
 101                 first = i;
 102             last = i;
 103         }
 104         addr += src_width;
 105         src += src_width;
 106         dest += dest_row_pitch;
 107     }
 108     cpu_physical_memory_unmap(src_base, src_len, 0, 0);
 109     if (first < 0) {
 110         return;
 111     }
 112     cpu_physical_memory_reset_dirty(pd, pd + src_len, VGA_DIRTY_FLAG);
 113     *first_row = first;
 114     *last_row = last;
 115     return;
 116 }