libgs.c

/*
# _____     ___ ____     ___ ____
#  ____|   |    ____|   |        | |____|
# |     ___|   |____ ___|    ____| |    \    PS2DEV Open Source Project.
#-----------------------------------------------------------------------
# (c) 2009 Lion
# Licenced under Academic Free License version 2.0
# Review ps2sdk README & LICENSE files for further details.
*/
 
#include <errno.h>
#include <stdio.h>
#include <kernel.h>
#include <libgs.h>
 
#include "internal.h"
 
extern QWORD GsPrimWorkArea[];
 
/* Initialization functions. */
 
static GsGParam_t gp_15;
 
GsGParam_t *GsGetGParam(void)
{
    if (!gp_15.version)
    {
        gp_15.interlace = GS_INTERLACED;
        gp_15.omode = GS_MODE_NTSC;
        gp_15.ffmode = GS_FFMD_FRAME;
        gp_15.version = 3;
    }
    return &gp_15;
}
 
void GsResetGraph(s16 mode, s16 interlace, s16 omode, s16 ffmode)
{
    GsGParam_t *pGParams;
 
    switch(mode){
        case GS_INIT_RESET:
            GsDmaInit();    //It seems like the Sony developers reset the GIF DMA channel with their libdma library, but a lot of homebrew GS libraries will do this on their own.
 
            pGParams=GsGetGParam();
            GS_SET_CSR_reset(1);
            pGParams->ffmode=ffmode;
            pGParams->interlace=interlace;
            pGParams->omode=omode;
            pGParams->version=GS_GET_CSR_gs_rev_number>>16;
 
            GsPutIMR(0xFF00);
 
            SetGsCrt(interlace&1, omode&0xFF, ffmode&1);
            GsSetCRTCSettings(CRTC_SETTINGS_DEFAULT1, 0x80);
            break;
        case GS_INIT_DRAW_RESET:
            GS_SET_CSR_flush(1);
            break;
    /*  There is a mode 5 present in the Sony sceGsResetGraph, but is not documented. It seems to change the video mode without resetting anything. */
    }
}
 
void GsSetCRTCSettings(u64 settings, u8 alpha_value)
{
    *((vu64 *)(gs_p_pmode)) =  (settings|((u64)(0x001) << 2)|((u64)(alpha_value)    << 8));
}