diff options
Diffstat (limited to 'src/stream/ide_stream.c')
-rw-r--r-- | src/stream/ide_stream.c | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/src/stream/ide_stream.c b/src/stream/ide_stream.c new file mode 100644 index 0000000000..d05c6aab91 --- /dev/null +++ b/src/stream/ide_stream.c @@ -0,0 +1,119 @@ +#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_sector(int drive, void * buffer, unsigned int block, int byte_offset, + int n_bytes); +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 ide_read(void *vdest, byte_offset_t offset, byte_offset_t count) +{ + byte_offset_t bytes = 0; + unsigned char *dest = vdest; + + //printk_debug("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_sector(IDE_BOOT_DRIVE, buffer, block_num, + 0, 512); + 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 = 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; +} |