source: rtems/c/src/lib/libbsp/arm/nds/libnds/source/arm9/initSystem.c @ ef4c461

/*---------------------------------------------------------------------------------

        initSystem.c -- Code for initialising the DS

        Copyright (C) 2007
        Dave Murphy (WinterMute)

        This software is provided 'as-is', without any express or implied
        warranty.  In no event will the authors be held liable for any
        damages arising from the use of this software.

        Permission is granted to anyone to use this software for any
        purpose, including commercial applications, and to alter it and
        redistribute it freely, subject to the following restrictions:

        1.      The origin of this software must not be misrepresented; you
        must not claim that you wrote the original software. If you use
        this software in a product, an acknowledgment in the product
        documentation would be appreciated but is not required.

        2.      Altered source versions must be plainly marked as such, and
        must not be misrepresented as being the original software.

        3.      This notice may not be removed or altered from any source
        distribution.

---------------------------------------------------------------------------------*/
#include <nds/jtypes.h>
#include <nds/system.h>
#include <nds/memory.h>
#include <nds/timers.h>
#include <nds/dma.h>
#include <nds/ipc.h>
#include <nds/arm9/video.h>

#include <time.h>

/*
 * Prototypes
 *
 * NOTE: Called from start.S
 */
void initSystem(void);

extern time_t *punixTime;

//---------------------------------------------------------------------------------
// Reset the DS registers to sensible defaults
//---------------------------------------------------------------------------------
void initSystem(void) {
//---------------------------------------------------------------------------------
        register int i;

        //clear out ARM9 DMA channels
        for (i=0; i<4; i++) {
                DMA_CR(i) = 0;
                DMA_SRC(i) = 0;
                DMA_DEST(i) = 0;
                TIMER_CR(i) = 0;
                TIMER_DATA(i) = 0;
        }

        VRAM_CR = 0x80808080;
        VRAM_E_CR = 0x80;
        VRAM_F_CR = 0x80;
        VRAM_G_CR = 0x80;
        VRAM_H_CR = 0x80;
        VRAM_I_CR = 0x80;

        (*(vu32*)0x027FFE04) = 0;  // temporary variable
        PALETTE[0] = 0xFFFF;
        dmaFillWords((void*)0x027FFE04, PALETTE+1, (2*1024)-2);
        dmaFillWords((void*)0x027FFE04, OAM,    2*1024);
        dmaFillWords((void*)0x027FFE04, (void*)0x04000000, 0x56);  //clear main display registers
        dmaFillWords((void*)0x027FFE04, (void*)0x04001000, 0x56);  //clear sub  display registers
        dmaFillWords((void*)0x027FFE04, VRAM,  656*1024);

        REG_DISPSTAT = 0;
        videoSetMode(0);
        videoSetModeSub(0);
        VRAM_A_CR = 0;
        VRAM_B_CR = 0;
        VRAM_C_CR = 0;
        VRAM_D_CR = 0;
        VRAM_E_CR = 0;
        VRAM_F_CR = 0;
        VRAM_G_CR = 0;
        VRAM_H_CR = 0;
        VRAM_I_CR = 0;
        VRAM_CR  = 0x03000000;

        punixTime = (time_t*)&IPC->unixTime;

}