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     MemoryRegion *address_space,
  26     target_phys_addr_t base,
  27     int cols, /* Width in pixels.  */
  28     int rows, /* Leight in pixels.  */
  29     int src_width, /* Length of source line, in bytes.  */
  30     int dest_row_pitch, /* Bytes between adjacent horizontal output pixels.  */
  31     int dest_col_pitch, /* Bytes between adjacent vertical output pixels.  */
  32     int invalidate, /* nonzero to redraw the whole image.  */
  33     drawfn fn,
  34     void *opaque,
  35     int *first_row, /* Input and output.  */
  36     int *last_row /* Output only */)
  37 {
  38     target_phys_addr_t src_len;
  39     uint8_t *dest;
  40     uint8_t *src;
  41     uint8_t *src_base;
  42     int first, last = 0;
  43     int dirty;
  44     int i;
  45     ram_addr_t addr;
  46     MemoryRegionSection mem_section;
  47     MemoryRegion *mem;
  48
  49     i = *first_row;
  50     *first_row = -1;
  51     src_len = src_width * rows;
  52
  53     mem_section = memory_region_find(address_space, base, src_len);
  54     if (mem_section.size != src_len || !memory_region_is_ram(mem_section.mr)) {
  55         return;
  56     }
  57     mem = mem_section.mr;
  58     assert(mem);
  59     assert(mem_section.offset_within_address_space == base);
  60
  61     memory_region_sync_dirty_bitmap(mem);
  62     src_base = cpu_physical_memory_map(base, &src_len, 0);
  63     /* If we can't map the framebuffer then bail.  We could try harder,
  64        but it's not really worth it as dirty flag tracking will probably
  65        already have failed above.  */
  66     if (!src_base)
  67         return;
  68     if (src_len != src_width * rows) {
  69         cpu_physical_memory_unmap(src_base, src_len, 0, 0);
  70         return;
  71     }
  72     src = src_base;
  73     dest = ds_get_data(ds);
  74     if (dest_col_pitch < 0)
  75         dest -= dest_col_pitch * (cols - 1);
  76     if (dest_row_pitch < 0) {
  77         dest -= dest_row_pitch * (rows - 1);
  78     }
  79     first = -1;
  80     addr = mem_section.offset_within_region;
  81
  82     addr += i * src_width;
  83     src += i * src_width;
  84     dest += i * dest_row_pitch;
  85
  86     for (; i < rows; i++) {
  87         target_phys_addr_t dirty_offset;
  88         dirty = 0;
  89         dirty_offset = 0;
  90         while (addr + dirty_offset < TARGET_PAGE_ALIGN(addr + src_width)) {
  91             dirty |= memory_region_get_dirty(mem, addr + dirty_offset,
  92                                              DIRTY_MEMORY_VGA);
  93             dirty_offset += TARGET_PAGE_SIZE;
  94         }
  95
  96         if (dirty || invalidate) {
  97             fn(opaque, dest, src, cols, dest_col_pitch);
  98             if (first == -1)
  99                 first = i;
 100             last = i;
 101         }
 102         addr += src_width;
 103         src += src_width;
 104         dest += dest_row_pitch;
 105     }
 106     cpu_physical_memory_unmap(src_base, src_len, 0, 0);
 107     if (first < 0) {
 108         return;
 109     }
 110     memory_region_reset_dirty(mem, mem_section.offset_within_region, src_len,
 111                               DIRTY_MEMORY_VGA);
 112     *first_row = first;
 113     *last_row = last;
 114     return;
 115 }