/*
 * Copyright 2010 Haiku, Inc.  All rights reserved.
 * Distributed under the terms of the MIT license.
 *
 * Authors:
 *              Gerald Zajac
 */

#include "accelerant.h"
#include "3dfx.h"



uint32
TDFX_GetVideoMemorySize(void)
{
        // Return the number of bytes of video memory.

        uint32  chipSize;               // size is in megabytes
        uint32  dramInit0 = INREG32(DRAM_INIT0);
        uint32  dramInit1 = INREG32(DRAM_INIT1);
        uint32  numChips = (dramInit0 & SGRAM_NUM_CHIPSETS) ? 8 : 4;
        int             memType = (dramInit1 & MCTL_TYPE_SDRAM) ? MEM_TYPE_SDRAM : MEM_TYPE_SGRAM;

        if (gInfo.sharedInfo->chipType == VOODOO_5) {
                chipSize = 1 << ((dramInit0 >> 27) & 0x7);
        } else {
                // Banshee or Voodoo3
                if (memType == MEM_TYPE_SDRAM)
                        chipSize = 2;
                else
                        chipSize = (dramInit0 & SGRAM_TYPE) ? 2 : 1;
        }

        // Disable block writes for SDRAM.

        uint32 miscInit1 = INREG32(MISC_INIT1);
        if (memType == MEM_TYPE_SDRAM) {
                miscInit1 |= DISABLE_2D_BLOCK_WRITE;
        }
        miscInit1 |= 1;
        OUTREG32(MISC_INIT1, miscInit1);

        return chipSize * numChips * 1024 * 1024;
}


status_t
TDFX_Init(void)
{
        TRACE("TDFX_Init()\n");

        SharedInfo& si = *gInfo.sharedInfo;

        si.videoMemSize = TDFX_GetVideoMemorySize();

        si.cursorOffset = 0;
        si.frameBufferOffset = si.cursorOffset + CURSOR_BYTES;
        si.maxFrameBufferSize = si.videoMemSize - si.frameBufferOffset;

        TRACE("Video Memory size: %d MB\n", si.videoMemSize / 1024 / 1024);
        TRACE("frameBufferOffset: 0x%x  cursorOffset: 0x%x\n", 
                si.frameBufferOffset, si.cursorOffset);

        switch (si.chipType) {
                case BANSHEE:
                        si.maxPixelClock = 270000;
                        break;
                case VOODOO_3:
                        si.maxPixelClock = 300000;
                        break;
                case VOODOO_5:
                        si.maxPixelClock = 350000;
                        break;
                default:
                        TRACE("Undefined chip type: %d\n", si.chipType);
                        return B_ERROR;
        }

        // Set up the array of color spaces supported by the 3dfx chips.

        si.colorSpaces[0] = B_CMAP8;
        si.colorSpaces[1] = B_RGB16;
        si.colorSpaces[2] = B_RGB32;
        si.colorSpaceCount = 3;

        // Setup the mode list.

        return CreateModeList(IsModeUsable);
}