/// <summary>
/// Read sectors into the output buffer and return size in bytes
/// </summary>
/// <param name="num">The disk number</param>
/// <param name="lba">Input LBA</param>
/// <param name="size">Size in sectors</param>
/// <param name="buffer">Output buffer</param>
/// <returns>The amount of bytes read</returns>
public static int ReadSector(int num, uint lba, byte size, byte[] buffer)
{
// The driver only supports up to 4 drives
if (num >= 4)
{
return(0);
}
// Get IDE device from array
IDE_Device device = Devices[num];
if (!device.Exists)
{
return(0);
}
uint port = device.BasePort;
int drive = device.Drive;
int cmd = (drive == ATA_MASTER) ? 0xE0 : 0xF0;
// Set Drive
PortIO.Out8((ushort)(port + ATA_REG_DRIVE), (byte)(cmd | (byte)((lba >> 24) & 0x0F)));
// Set PIO MODE
PortIO.Out8((ushort)(port + ATA_REG_FEATURE), ATA_FEATURE_PIO);
// Set size
PortIO.Out8((ushort)(port + ATA_REG_SECCNT), size);
// Set LBA
PortIO.Out8((ushort)(port + ATA_REG_LBALO), (byte)lba);
PortIO.Out8((ushort)(port + ATA_REG_LBAMID), (byte)(lba >> 8));
PortIO.Out8((ushort)(port + ATA_REG_LBAHI), (byte)(lba >> 16));
// Issue command
PortIO.Out8((ushort)(port + ATA_REG_CMD), ATA_CMD_PIO_READ);
// Wait till done
poll(port);
// Read data
int offset = 0;
for (int i = 0; i < size * 256; i++)
{
ushort data = PortIO.In16((ushort)(port + ATA_REG_DATA));
buffer[offset + 0] = (byte)(data);
buffer[offset + 1] = (byte)(data >> 8);
offset += 2;
}
return(size * 512);
}
/// <summary>
/// IDE Prope
/// </summary>
private static unsafe void probe()
{
int num = 0;
// Let's prope 4 devices!
while (num < 4)
{
ushort port;
byte channel;
byte drive;
if (num <= 1)
{
port = ATA_PRIMARY_IO;
channel = ATA_PRIMARY;
}
else
{
port = ATA_SECONDARY_IO;
channel = ATA_SECONDARY;
}
if ((num % 2) != 0)
{
drive = ATA_SLAVE;
}
else
{
drive = ATA_PRIMARY;
}
Devices[num] = new IDE_Device();
Devices[num].BasePort = port;
Devices[num].Channel = channel;
Devices[num].Drive = drive;
byte[] result = identify(channel, drive);
if (result == null)
{
Devices[num].Exists = false;
num++;
continue;
}
Devices[num].Exists = true;
int pos = ATA_IDENT_COMMANDSETS;
Devices[num].CmdSet = (uint)((result[pos] << 24) | (result[pos + 1] << 16) | (result[pos + 2] << 8) | result[pos + 3]);
pos = ATA_IDENT_DEVICETYPE;
Devices[num].Type = (ushort)((result[pos + 1] << 8) | result[pos]);
pos = ATA_IDENT_CAPABILITIES;
Devices[num].Capabilities = (ushort)((result[pos + 1] << 8) | result[pos]);
pos = ATA_IDENT_CYLINDERS;
Devices[num].Cylinders = (ushort)((result[pos + 1] << 8) | result[pos]);
pos = ATA_IDENT_HEADS;
Devices[num].Heads = (ushort)((result[pos + 1] << 8) | result[pos]);
pos = ATA_IDENT_SECTORSPT;
Devices[num].Sectorspt = (ushort)((result[pos + 1] << 8) | result[pos]);
pos = ATA_IDENT_MAX_LBA;
Devices[num].Size = (uint)(((result[pos] << 24) | (result[pos + 1] << 16) | (result[pos + 2] << 8) | result[pos + 3]));
// Model name
pos = ATA_IDENT_MODEL;
// NULL-terminated string
char *name = (char *)Heap.Alloc(40 + 1);
fixed(void *source = &result[pos])
{
Memory.Memcpy(name, source, 40);
}
name[40] = '\0';
Devices[num].Name = Util.CharPtrToString(name);
num++;
}
}
/// <summary>
/// Write sector to drive and return size in bytes
/// </summary>
/// <param name="num">The disk number</param>
/// <param name="lba">Input LBA</param>
/// <param name="size">Output size in sectors</param>
/// <param name="buffer">Input buffer</param>
/// <returns>The amount of bytes written</returns>
public static int WriteSector(int num, uint lba, byte size, byte[] buffer)
{
// The driver only supports up to 4 drivers
if (num >= 4)
{
return(0);
}
// Get IDE device from array
IDE_Device device = Devices[num];
if (!device.Exists)
{
return(0);
}
uint port = device.BasePort;
int drive = device.Drive;
int cmd = (drive == ATA_MASTER) ? 0xE0 : 0xF0;
// Set Drive
PortIO.Out8((ushort)(port + ATA_REG_DRIVE), (byte)(cmd | (byte)((lba >> 24) & 0x0F)));
// Set PIO MODE
PortIO.Out8((ushort)(port + ATA_REG_FEATURE), ATA_FEATURE_PIO);
// Set size
PortIO.Out8((ushort)(port + ATA_REG_SECCNT), size);
// Set LBA
PortIO.Out8((ushort)(port + ATA_REG_LBALO), (byte)lba);
PortIO.Out8((ushort)(port + ATA_REG_LBAMID), (byte)(lba >> 8));
PortIO.Out8((ushort)(port + ATA_REG_LBAHI), (byte)(lba >> 16));
// Issue command
PortIO.Out8((ushort)(port + ATA_REG_CMD), ATA_CMD_PIO_WRITE);
// Wait till done
poll(port);
// Wait for 400ns
wait400ns(port);
// Write data
for (int i = 0; i < size * 256; i++)
{
int pos = i * 2;
ushort shrt = (ushort)((buffer[pos + 1] << 8) | buffer[pos]);
PortIO.Out16((ushort)(port + ATA_REG_DATA), shrt);
}
// Flush data
PortIO.Out8((ushort)(port + ATA_REG_CMD), ATA_CMD_FLUSH);
// Wait till done
byte status;
do
{
status = PortIO.In8((ushort)(port + ATA_REG_STATUS));
}while ((status & ATA_STATUS_BSY) > 0);
return(size * 512);
}
