Kernel: Expand PATA driver to support multiple hard drives (#365)

The previous implementation of the PIIX3/4 PATA/IDE channel driver only
supported a single drive, as the object model was wrong (the channel
inherits the IRQ, not the disk drive itself). This fixes it by 'attaching'
two `PATADiskDevices` to a `PATAChannel`, which makes more sense.

The reading/writing code is presented as is, which violates the spec
outlined by Seagate in the linked datasheet. That spec is rather old,
so it might not be 100% up to date, though may cause issues on real
hardware, so until we can actually test it, this will suffice.

Kernel/Devices/PATADiskDevice.cpp

@@ -0,0 +1,164 @@
+#include "PATADiskDevice.h"
+#include <Kernel/Arch/i386/PIC.h>
+#include <Kernel/FileSystem/ProcFS.h>
+#include <Kernel/IO.h>
+#include <Kernel/Process.h>
+#include <Kernel/StdLib.h>
+#include <Kernel/VM/MemoryManager.h>
+
+//#define DISK_DEBUG
+
+#define IRQ_FIXED_DISK 14
+
+#define ATA_SR_BSY 0x80
+#define ATA_SR_DRDY 0x40
+#define ATA_SR_DF 0x20
+#define ATA_SR_DSC 0x10
+#define ATA_SR_DRQ 0x08
+#define ATA_SR_CORR 0x04
+#define ATA_SR_IDX 0x02
+#define ATA_SR_ERR 0x01
+
+#define ATA_ER_BBK 0x80
+#define ATA_ER_UNC 0x40
+#define ATA_ER_MC 0x20
+#define ATA_ER_IDNF 0x10
+#define ATA_ER_MCR 0x08
+#define ATA_ER_ABRT 0x04
+#define ATA_ER_TK0NF 0x02
+#define ATA_ER_AMNF 0x01
+
+#define ATA_CMD_READ_PIO 0x20
+#define ATA_CMD_READ_PIO_EXT 0x24
+#define ATA_CMD_READ_DMA 0xC8
+#define ATA_CMD_READ_DMA_EXT 0x25
+#define ATA_CMD_WRITE_PIO 0x30
+#define ATA_CMD_WRITE_PIO_EXT 0x34
+#define ATA_CMD_WRITE_DMA 0xCA
+#define ATA_CMD_WRITE_DMA_EXT 0x35
+#define ATA_CMD_CACHE_FLUSH 0xE7
+#define ATA_CMD_CACHE_FLUSH_EXT 0xEA
+#define ATA_CMD_PACKET 0xA0
+#define ATA_CMD_IDENTIFY_PACKET 0xA1
+#define ATA_CMD_IDENTIFY 0xEC
+
+#define ATAPI_CMD_READ 0xA8
+#define ATAPI_CMD_EJECT 0x1B
+
+#define ATA_IDENT_DEVICETYPE 0
+#define ATA_IDENT_CYLINDERS 2
+#define ATA_IDENT_HEADS 6
+#define ATA_IDENT_SECTORS 12
+#define ATA_IDENT_SERIAL 20
+#define ATA_IDENT_MODEL 54
+#define ATA_IDENT_CAPABILITIES 98
+#define ATA_IDENT_FIELDVALID 106
+#define ATA_IDENT_MAX_LBA 120
+#define ATA_IDENT_COMMANDSETS 164
+#define ATA_IDENT_MAX_LBA_EXT 200
+
+#define IDE_ATA 0x00
+#define IDE_ATAPI 0x01
+
+#define ATA_REG_DATA 0x00
+#define ATA_REG_ERROR 0x01
+#define ATA_REG_FEATURES 0x01
+#define ATA_REG_SECCOUNT0 0x02
+#define ATA_REG_LBA0 0x03
+#define ATA_REG_LBA1 0x04
+#define ATA_REG_LBA2 0x05
+#define ATA_REG_HDDEVSEL 0x06
+#define ATA_REG_COMMAND 0x07
+#define ATA_REG_STATUS 0x07
+#define ATA_REG_SECCOUNT1 0x08
+#define ATA_REG_LBA3 0x09
+#define ATA_REG_LBA4 0x0A
+#define ATA_REG_LBA5 0x0B
+#define ATA_REG_CONTROL 0x0C
+#define ATA_REG_ALTSTATUS 0x0C
+#define ATA_REG_DEVADDRESS 0x0D
+
+NonnullRefPtr<PATADiskDevice> PATADiskDevice::create(PATAChannel& channel, DriveType type)
+{
+    return adopt(*new PATADiskDevice(channel, type));
+}
+
+PATADiskDevice::PATADiskDevice(PATAChannel& channel, DriveType type)
+    : m_drive_type(type)
+    , m_channel(channel)
+{
+}
+
+PATADiskDevice::~PATADiskDevice()
+{
+}
+
+const char* PATADiskDevice::class_name() const
+{
+    return "PATADiskDevice";
+}
+
+unsigned PATADiskDevice::block_size() const
+{
+    return 512;
+}
+
+bool PATADiskDevice::read_blocks(unsigned index, u16 count, u8* out)
+{
+    if (m_channel.m_bus_master_base && m_channel.m_dma_enabled.resource())
+        return read_sectors_with_dma(index, count, out);
+    return read_sectors(index, count, out);
+}
+
+bool PATADiskDevice::read_block(unsigned index, u8* out) const
+{
+    return const_cast<PATADiskDevice*>(this)->read_blocks(index, 1, out);
+}
+
+bool PATADiskDevice::write_blocks(unsigned index, u16 count, const u8* data)
+{
+    if (m_channel.m_bus_master_base && m_channel.m_dma_enabled.resource())
+        return write_sectors_with_dma(index, count, data);
+    for (unsigned i = 0; i < count; ++i) {
+        if (!write_sectors(index + i, 1, data + i * 512))
+            return false;
+    }
+    return true;
+}
+
+bool PATADiskDevice::write_block(unsigned index, const u8* data)
+{
+    return write_blocks(index, 1, data);
+}
+
+void PATADiskDevice::set_drive_geometry(u16 cyls, u16 heads, u16 spt)
+{
+    m_cylinders = cyls;
+    m_heads = heads;
+    m_sectors_per_track = spt;
+}
+
+bool PATADiskDevice::read_sectors_with_dma(u32 lba, u16 count, u8* outbuf)
+{
+    return m_channel.ata_read_sectors_with_dma(lba, count, outbuf, is_slave());
+}
+
+bool PATADiskDevice::read_sectors(u32 start_sector, u16 count, u8* outbuf)
+{
+    return m_channel.ata_read_sectors(start_sector, count, outbuf, is_slave());
+}
+
+bool PATADiskDevice::write_sectors_with_dma(u32 lba, u16 count, const u8* inbuf)
+{
+    return m_channel.ata_write_sectors_with_dma(lba, count, inbuf, is_slave());
+}
+
+bool PATADiskDevice::write_sectors(u32 start_sector, u16 count, const u8* inbuf)
+{
+    return m_channel.ata_write_sectors(start_sector, count, inbuf, is_slave());
+}
+
+bool PATADiskDevice::is_slave() const
+{
+    return m_drive_type == DriveType::Slave;
+}