1 /*---------------------------------------------------------------------------*
2   Project:  TwlSDK - OS
3   File:     os_entropy.c
4 
5   Copyright 2003-2008 Nintendo. All rights reserved.
6 
7   These coded instructions, statements, and computer programs contain
8   proprietary information of Nintendo of America Inc. and/or Nintendo
9   Company Ltd., and are protected by Federal copyright law. They may
10   not be disclosed to third parties or copied or duplicated in any form,
11   in whole or in part, without the prior written consent of Nintendo.
12 
13   $Date:: 2008-09-18#$
14   $Rev: 8573 $
15   $Author: okubata_ryoma $
16  *---------------------------------------------------------------------------*/
17 #include <nitro/os.h>
18 #include <nitro/gx.h>
19 
20 //----------------------------------------------------------------------
21 
22 extern vu64 OSi_TickCounter;
23 
24 /*---------------------------------------------------------------------------*
25   Name:         OS_GetLowEntropyData
26 
27   Description:  Gets low entropy data array that changes according to the system status.
28 
29   Arguments:    buffer: Pointer to the array that holds the data string
30 
31   Returns:      None.
32  *---------------------------------------------------------------------------*/
OS_GetLowEntropyData(u32 buffer[OS_LOW_ENTROPY_DATA_SIZE/sizeof (u32)])33 void OS_GetLowEntropyData(u32 buffer[OS_LOW_ENTROPY_DATA_SIZE / sizeof(u32)])
34 {
35     // RTC work area in the System Work Memory
36     const OSSystemWork *work = OS_GetSystemWork();
37     const u8 *macAddress =
38         (u8 *)((u32)(work->nvramUserInfo) + ((sizeof(NVRAMConfig) + 3) & ~0x00000003));
39 
40     buffer[0] = (u32)((GX_GetVCount() << 16) | OS_GetTickLo());
41     buffer[1] = (u32)(*(u16 *)(macAddress + 4) << 16) ^ (u32)(OSi_TickCounter);
42     buffer[2] = (u32)(OSi_TickCounter >> 32) ^ *(u32 *)macAddress ^ work->vblankCount;
43 #ifdef reg_G3X_GXSTAT
44     buffer[2] ^= reg_G3X_GXSTAT;
45 #endif
46     buffer[3] = *(u32 *)(&work->real_time_clock[0]);
47     buffer[4] = *(u32 *)(&work->real_time_clock[4]);
48     buffer[5] = (((u32)work->mic_sampling_data) << 16) ^ work->mic_last_address;
49     buffer[6] = (u32)((*(u16 *)(&work->touch_panel[0]) << 16) | *(u16 *)(&work->touch_panel[2]));
50     buffer[7] = (u32)((work->wm_rssi_pool << 16) | (reg_PAD_KEYINPUT | *(vu16 *)HW_BUTTON_XY_BUF));
51 }
52