luxos/Kernel/drivers/dma/dma.c

/*
 * dma.c
 *
 *  Created on: Aug 20, 2011
 *      Author: Tiberiu
 */

#include <stdio.h>
#include "dma.h"

void DmaSetAddress (uint8 channel, uint8 low, uint8 high)
{
	uint16 port = 0;

	switch (channel)
	{
		case 0: port = DmaRegisterChannel0Address; break;
		case 1: port = DmaRegisterChannel1Address; break;
		case 2: port = DmaRegisterChannel2Address; break;
		case 3: port = DmaRegisterChannel3Address; break;
		case 4: port = DmaRegisterChannel4Address; break;
		case 5: port = DmaRegisterChannel5Address; break;
		case 6: port = DmaRegisterChannel6Address; break;
		case 7: port = DmaRegisterChannel7Address; break;
		default: return;
	}

	outportb(port, low); iowait();
	outportb(port, high);
}

void DmaSetCount (uint8 channel, uint8 low, uint8 high)
{
	uint16 port = 0;

	switch (channel)
	{
		case 0: port = DmaRegisterChannel0Count; break;
		case 1: port = DmaRegisterChannel1Count; break;
		case 2: port = DmaRegisterChannel2Count; break;
		case 3: port = DmaRegisterChannel3Count; break;
		case 4: port = DmaRegisterChannel4Count; break;
		case 5: port = DmaRegisterChannel5Count; break;
		case 6: port = DmaRegisterChannel6Count; break;
		case 7: port = DmaRegisterChannel7Count; break;
		default: return;
	}

	outportb(port, low); iowait();
	outportb(port, high);
}

void DmaSetExternalPageRegisters (uint8 channel, uint8 val)
{
	uint16 port = 0;

	switch (channel)
	{
		case 1: port = DmaRegisterChannel1PageAddress; break;
		case 2: port = DmaRegisterChannel2PageAddress; break;
		case 3: port = DmaRegisterChannel3PageAddress; break;
		case 5: port = DmaRegisterChannel5PageAddress; break;
		case 6: port = DmaRegisterChannel6PageAddress; break;
		case 7: port = DmaRegisterChannel7PageAddress; break;
		default: return;
	}

	outportb(port, val);
}

void DmaResetFlipFlop (uint8 channel)
{
	uint16 port = (channel < 4) ? DmaRegisterFlipFlopReset : 2*DmaRegisterFlipFlopReset+0xC0;
	outportb(port, 0);
}

void DmaReset ()
{
	outportb(DmaRegisterMasterReset, 0);
}

void DmaUnmaskAll()
{
	outportb(DmaRegisterMaskReset, 0);
}

void DmaMaskChannel(uint8 channel)
{
	if (channel >= 8) return;
	uint16 port = (channel < 4) ? (DmaRegisterSingleChannelMask) : (2*DmaRegisterSingleChannelMask + 0xC0);

	outportb(port, channel%4 | 4);
}

void DmaUnmaskChannel (uint8 channel)
{
	if (channel >= 8) return;
	uint16 port = (channel < 4) ? (DmaRegisterSingleChannelMask) : (2*DmaRegisterSingleChannelMask + 0xC0);

	outportb(port, channel%4);
}

void DmaSetMode (uint8 channel, uint8 mode)
{
	if (channel >= 8) return;
	uint16 port = (channel < 4) ? (DmaRegisterMode) : (2*DmaRegisterMode + 0xC0);

	DmaMaskChannel(channel);
	outportb(port, (channel%4) | mode );
	DmaUnmaskAll();
}