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-rw-r--r--src/stream/ide_stream.c119
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;
+}