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#include <console/console.h>
#include <stdlib.h>
#include <stddef.h>
#include <stream/read_bytes.h>
#include <delay.h>
#include <string.h>
/* read a sector or a partial sector */
extern int ide_read(int drive, unsigned long block, void * buffer);
extern int ide_init(void);
static unsigned long offset;
int stream_init(void)
{
int i,res;
printk_debug ("Trying polled ide\n");
printk_debug ("Waiting for ide disks to spin up\n");
printk_notice ("This is a hard coded delay and longer than necessary.\n");
for (i = 0; i < 2; i++) {
printk_notice (".");
delay(1);
}
printk_info ("\n");
#ifdef ONE_TRACK
offset = (ONE_TRACK*512);
#elif defined(IDE_OFFSET)
offset = IDE_OFFSET;
#else
offset = 0x7e00;
#endif
res = ide_init();
delay(1);
return res;
}
void stream_fini(void)
{
return;
}
#ifdef IDE_SWAB
/* from string/swab.c */
void
swab (const char *from, char *to, int n)
{
n &= ~1;
while (n > 1)
{
const char b0 = from[--n], b1 = from[--n];
to[n] = b0;
to[n + 1] = b1;
}
}
#endif
static unsigned char buffer[512];
static unsigned int block_num = 0;
static unsigned int first_fill = 1;
#ifndef IDE_BOOT_DRIVE
#define IDE_BOOT_DRIVE 0
#endif
static byte_offset_t stream_ide_read(void *vdest, byte_offset_t offset, byte_offset_t count)
{
byte_offset_t bytes = 0;
unsigned char *dest = vdest;
//printk_debug("stream_ide_read count = %x\n", count);
while (bytes < count) {
unsigned int byte_offset, len;
/* The block is not cached in memory or frist time called */
if (block_num != offset / 512 || first_fill) {
block_num = offset / 512;
printk_notice (".");
ide_read(IDE_BOOT_DRIVE, block_num, buffer);
first_fill = 0;
}
byte_offset = offset % 512;
len = 512 - byte_offset;
if (len > (count - bytes)) {
len = (count - bytes);
}
#ifdef IDE_SWAB
swab(buffer + byte_offset, dest, len);
#else
memcpy(dest, buffer + byte_offset, len);
#endif
offset += len;
bytes += len;
dest += len;
}
return bytes;
}
byte_offset_t stream_read(void *vdest, byte_offset_t count)
{
byte_offset_t len;
len = stream_ide_read(vdest, offset, count);
if (len > 0) {
offset += len;
}
return len;
}
byte_offset_t stream_skip(byte_offset_t count)
{
offset += count;
return count;
}
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