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 #include "kvm.h"
  21
  22 /* Render an image from a shared memory framebuffer.  */
  23
  24 void framebuffer_update_display(
  25     DisplayState *ds,
  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     ram_addr_t pd;
  47     ram_addr_t pd2;
  48
  49     i = *first_row;
  50     *first_row = -1;
  51     src_len = src_width * rows;
  52
  53     if (kvm_enabled()) {
  54         kvm_physical_sync_dirty_bitmap(base, src_len);
  55     }
  56     pd = cpu_get_physical_page_desc(base);
  57     pd2 = cpu_get_physical_page_desc(base + src_len - 1);
  58     /* We should reall check that this is a continuous ram region.
  59        Instead we just check that the first and last pages are
  60        both ram, and the right distance apart.  */
  61     if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM
  62         || (pd2 & ~TARGET_PAGE_MASK) > IO_MEM_ROM) {
  63         return;
  64     }
  65     pd = (pd & TARGET_PAGE_MASK) + (base & ~TARGET_PAGE_MASK);
  66     if (((pd + src_len - 1) & TARGET_PAGE_MASK) != (pd2 & TARGET_PAGE_MASK)) {
  67         return;
  68     }
  69
  70     src_base = cpu_physical_memory_map(base, &src_len, 0);
  71     /* If we can't map the framebuffer then bail.  We could try harder,
  72        but it's not really worth it as dirty flag tracking will probably
  73        already have failed above.  */
  74     if (!src_base)
  75         return;
  76     if (src_len != src_width * rows) {
  77         cpu_physical_memory_unmap(src_base, src_len, 0, 0);
  78         return;
  79     }
  80     src = src_base;
  81     dest = ds_get_data(ds);
  82     if (dest_col_pitch < 0)
  83         dest -= dest_col_pitch * (cols - 1);
  84     first = -1;
  85     addr = pd;
  86
  87     addr += i * src_width;
  88     src += i * src_width;
  89     dest += i * dest_row_pitch;
  90
  91     for (; i < rows; i++) {
  92         target_phys_addr_t dirty_offset;
  93         dirty = 0;
  94         dirty_offset = 0;
  95         while (addr + dirty_offset < TARGET_PAGE_ALIGN(addr + src_width)) {
  96             dirty |= cpu_physical_memory_get_dirty(addr + dirty_offset,
  97                                                    VGA_DIRTY_FLAG);
  98             dirty_offset += TARGET_PAGE_SIZE;
  99         }
 100
 101         if (dirty || invalidate) {
 102             fn(opaque, dest, src, cols, dest_col_pitch);
 103             if (first == -1)
 104                 first = i;
 105             last = i;
 106         }
 107         addr += src_width;
 108         src += src_width;
 109         dest += dest_row_pitch;
 110     }
 111     cpu_physical_memory_unmap(src_base, src_len, 0, 0);
 112     if (first < 0) {
 113         return;
 114     }
 115     cpu_physical_memory_reset_dirty(pd, pd + src_len, VGA_DIRTY_FLAG);
 116     *first_row = first;
 117     *last_row = last;
 118     return;
 119 }