src/stream/rom_stream.c

   1 #include <console/console.h>
   2 #include <stdlib.h>
   3 #include <stddef.h>
   4 #include <stream/read_bytes.h>
   5 #include <string.h>
   6
   7
   8 #ifndef CONFIG_ROM_STREAM_START
   9 #define CONFIG_ROM_STREAM_START 0xffff0000UL
  10 #endif
  11
  12 static const unsigned char *rom_start = (void *)CONFIG_ROM_STREAM_START;
  13 static const unsigned char *rom_end   = (void *)(CONFIG_ROM_STREAM_START + PAYLOAD_SIZE - 1);
  14 static const unsigned char *rom;
  15
  16 int stream_init(void)
  17 {
  18         rom = rom_start;
  19
  20         printk_spew("%6d:%s() - rom_stream: 0x%08lx - 0x%08lx\n"
  21                 __LINE__, __FUNCTION__,
  22                 (unsigned long)rom_start,
  23                 (unsigned long)rom_end);
  24         return 0;
  25 }
  26
  27
  28 void stream_fini(void)
  29 {
  30         return;
  31 }
  32
  33 byte_offset_t stream_skip(byte_offset_t count)
  34 {
  35         byte_offset_t bytes;
  36         bytes = count;
  37         if ((rom + bytes) > rom_end) {
  38                 printk_warning("%6d:%s() - overflowed source buffer\n",
  39                         __LINE__, __FUNCTION__);
  40                 bytes = 0;
  41                 if (rom <= rom_end) {
  42                         bytes = (rom_end - rom) + 1;
  43                 }
  44         }
  45         rom += bytes;
  46         return bytes;
  47 }
  48
  49 byte_offset_t stream_read(void *vdest, byte_offset_t count)
  50 {
  51         unsigned char *dest = vdest;
  52         const unsigned char *src = rom;
  53         byte_offset_t bytes;
  54
  55         bytes = stream_skip(count);
  56         memcpy(dest, src, bytes);
  57         return bytes;
  58 }