1 files changed, 53 insertions, 0 deletions

diff --git a/firmware/sdmmc.c b/firmware/sdmmc.c
new file mode 100644
index 0000000000..f499ffae08
--- /dev/null
+++ b/firmware/sdmmc.c
@@ -0,0 +1,53 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2004 by Jens Arnold
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include <stdbool.h>
+#include "config.h"
+#if (CONFIG_STORAGE & STORAGE_MMC)
+#include "ata_mmc.h"
+#else
+#include "sdmmc.h"
+#endif
+
+/* helper function to extract n (<=32) bits from an arbitrary position.
+   counting from MSB to LSB */
+unsigned long card_extract_bits(
+    const unsigned long *p, /* the start of the bitfield array */
+    unsigned int start,     /* bit no. to start reading  */
+    unsigned int size)      /* how many bits to read */
+{
+    unsigned int long_index, bit_index;
+    unsigned long result;
+
+    /* we assume words of CSD/CID are stored most significant word first */
+    start = 127 - start;
+
+    long_index = start / 32;
+    bit_index = start % 32;
+    
+    result = p[long_index] << bit_index;
+
+    if (bit_index + size > 32)    /* crossing longword boundary */
+        result |= p[long_index+1] >> (32 - bit_index);
+        
+    result >>= 32 - size;
+
+    return result;
+}