[Backup & Restore] Performance changes

- Use always aligned buffers to up the speed for DMA usage. For verification, backup and restore.
- Rework verification a little bit and make default Sparse mode.

Sparse mode protects from fake sd cards, bad sectors and frequent I/O corruption. Aka, ~100% of cases.

bootloader/utils/util.c

@@ -120,31 +120,3 @@ u32 crc32c(const void *buf, u32 len)
 	}
 	return ~crc;
 }
-
-u32 memcmp32sparse(const u32 *buf1, const u32 *buf2, u32 len)
-{
-	u32 len32 = len / 4;
-
-	if (!(len32 % 32))
-	{
-		while (len32)
-		{
-			len32 -= 32;
-			if(buf1[len32] != buf2[len32])
-				return 1;
-		}
-	}
-	else
-	{
-		while (len32)
-		{
-			len32 -= 32;
-			if(buf1[len32] != buf2[len32])
-				return 1;
-			if (len32 < 32)
-				return 0;
-		}
-	}
-
-	return 0;
-}

bootloader/utils/util.h

@@ -41,8 +41,4 @@ void power_off();
 void exec_cfg(u32 *base, const cfg_op_t *ops, u32 num_ops);
 u32 crc32c(const void *buf, u32 len);
 
-/* This is a faster implementation of memcmp that checks two u32 values */
-/* every 128 Bytes block. Intented only for Backup and Restore          */
-u32 memcmp32sparse(const u32 *buf1, const u32 *buf2, u32 len);
-
 #endif