/*
 * Copyright 2021, Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 */


#include "FwCfg.h"

#include <stdlib.h>
#include <string.h>
#include <malloc.h>

#include <ByteOrder.h>
#include <Htif.h>
#include <KernelExport.h>

#include "graphics.h"


FwCfgRegs *volatile gFwCfgRegs = NULL;


namespace FwCfg {

void
Select(uint16_t selector)
{
        // GCC, why are you so crazy?
        // gFwCfgRegs->selector = B_BENDIAN_TO_HOST_INT16(selector);
        *(uint16*)0x10100008 = B_BENDIAN_TO_HOST_INT16(selector);
}


void
DmaOp(uint8_t *bytes, size_t count, uint32_t op)
{
        __attribute__ ((aligned (8))) FwCfgDmaAccess volatile dma;
        dma.control = B_HOST_TO_BENDIAN_INT32(1 << op);
        dma.length = B_HOST_TO_BENDIAN_INT32(count);
        dma.address = B_HOST_TO_BENDIAN_INT64((addr_t)bytes);
        // gFwCfgRegs->dmaAdr = B_HOST_TO_BENDIAN_INT64((addr_t)&dma);
        *(uint64*)0x10100010 = B_HOST_TO_BENDIAN_INT64((addr_t)&dma);
        while (uint32_t control = B_BENDIAN_TO_HOST_INT32(dma.control) != 0) {
                if (((1 << fwCfgDmaFlagsError) & control) != 0)
                        abort();
        }
}


void
ReadBytes(uint8_t *bytes, size_t count)
{
        DmaOp(bytes, count, fwCfgDmaFlagsRead);
}


void
WriteBytes(uint8_t *bytes, size_t count)
{
        DmaOp(bytes, count, fwCfgDmaFlagsWrite);
}


uint8_t  Read8 () {uint8_t  val; ReadBytes(          &val, sizeof(val)); return val;}
uint16_t Read16() {uint16_t val; ReadBytes((uint8_t*)&val, sizeof(val)); return val;}
uint32_t Read32() {uint32_t val; ReadBytes((uint8_t*)&val, sizeof(val)); return val;}
uint64_t Read64() {uint64_t val; ReadBytes((uint8_t*)&val, sizeof(val)); return val;}


void
ListDir()
{
        uint32_t count = B_BENDIAN_TO_HOST_INT32(Read32());
        dprintf("count: %" B_PRIu32 "\n", count);
        for (uint32_t i = 0; i < count; i++) {
                FwCfgFile file;
                ReadBytes((uint8_t*)&file, sizeof(file));
                file.size = B_BENDIAN_TO_HOST_INT32(file.size);
                file.select = B_BENDIAN_TO_HOST_INT16(file.select);
                file.reserved = B_BENDIAN_TO_HOST_INT16(file.reserved);
                dprintf("\n");
                dprintf("size: %" B_PRIu32 "\n", file.size);
                dprintf("select: %" B_PRIu32 "\n", file.select);
                dprintf("reserved: %" B_PRIu32 "\n", file.reserved);
                dprintf("name: %s\n", file.name);
        }
}


bool
ThisFile(FwCfgFile& file, uint16_t dir, const char *name)
{
        Select(dir);
        uint32_t count = B_BENDIAN_TO_HOST_INT32(Read32());
        for (uint32_t i = 0; i < count; i++) {
                ReadBytes((uint8_t*)&file, sizeof(file));
                file.size = B_BENDIAN_TO_HOST_INT32(file.size);
                file.select = B_BENDIAN_TO_HOST_INT16(file.select);
                file.reserved = B_BENDIAN_TO_HOST_INT16(file.reserved);
                if (strcmp(file.name, name) == 0)
                        return true;
        }
        return false;
}


void
InitFramebuffer()
{
        FwCfgFile file;
        if (!ThisFile(file, fwCfgSelectFileDir, "etc/ramfb")) {
                dprintf("[!] ramfb not found\n");
                return;
        }
        dprintf("file.select: %" B_PRIu16 "\n", file.select);

        RamFbCfg cfg;
        uint32_t width = 1024, height = 768;

        gFramebuf.colors = (uint32_t*)malloc(4*width*height);
        gFramebuf.stride = width;
        gFramebuf.width = width;
        gFramebuf.height = height;

        cfg.addr = B_HOST_TO_BENDIAN_INT64((size_t)gFramebuf.colors);
        cfg.fourcc = B_HOST_TO_BENDIAN_INT32(ramFbFormatXrgb8888);
        cfg.flags = B_HOST_TO_BENDIAN_INT32(0);
        cfg.width = B_HOST_TO_BENDIAN_INT32(width);
        cfg.height = B_HOST_TO_BENDIAN_INT32(height);
        cfg.stride = B_HOST_TO_BENDIAN_INT32(4 * width);
        Select(file.select);
        WriteBytes((uint8_t*)&cfg, sizeof(cfg));
}


void
Init()
{
        dprintf("gFwCfgRegs: 0x%08" B_PRIx64 "\n", (addr_t)gFwCfgRegs);
        if (gFwCfgRegs == NULL)
                return;
        Select(fwCfgSelectSignature);
        dprintf("fwCfgSelectSignature: 0x%08" B_PRIx32 "\n", Read32());
        Select(fwCfgSelectId);
        dprintf("fwCfgSelectId: : 0x%08" B_PRIx32 "\n", Read32());
        Select(fwCfgSelectFileDir);
        ListDir();
        InitFramebuffer();
}


};