Kernel: Remove the floppy driver

Nobody was using this code, and it was not actively worked on, so let's
just not have it. Press F.

Kernel/Devices/FloppyDiskDevice.cpp

@@ -1,565 +0,0 @@
-/*
- * Copyright (c) 2019-2020, Jesse Buhagiar <jooster669@gmail.com>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright notice, this
- *    list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright notice,
- *    this list of conditions and the following disclaimer in the documentation
- *    and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <AK/Memory.h>
-#include <Kernel/Devices/FloppyDiskDevice.h>
-#include <Kernel/VM/MemoryManager.h>
-#include <LibBareMetal/IO.h>
-
-namespace Kernel {
-
-// Uncomment me for a LOT of output
-//#define FLOPPY_DEBUG
-
-// THESE ARE OFFSETS!
-#define FLOPPY_STATUS_A 0x00 // ro
-#define FLOPPY_STATUS_B 0x01 // ro
-#define FLOPPY_DOR 0x02      // rw
-#define FLOPPY_TDR 0x03      // rw
-#define FLOPPY_MSR 0x04      // ro
-#define FLOPPY_DSR 0x04      // wo
-#define FLOPPY_FIFO 0x05
-#define FLOPPY_RSVD 0x06
-#define FLOPPY_DIR 0x07 // ro
-#define FLOPPY_CCR 0x07 // wo
-
-#define FLOPPY_STATUS_DIR 0x01
-#define FLOPPY_STATUS_WP 0x02
-#define FLOPPY_STATUS_INDX 0x04
-#define FLOPPY_STATUS_HDSEL 0x08
-#define FLOPPY_STATUS_TRK0 0x10
-#define FLOPPY_STATUS_STEP 0x20
-#define FLOPPY_STATUS_DRV2 0x40
-#define FLOPPY_STATUS_INTW 0x80 // A.K.A INT_PENDING
-
-#define FLOPPY_DOR_DRVSEL0 0x01
-#define FLOPPY_DOR_DRVSEL1 0x02
-#define FLOPPY_DOR_RESET 0x04
-#define FLOPPY_DOR_DMAGATE 0x08
-#define FLOPPY_DOR_MOTEN0 0x10
-#define FLOPPY_DOR_MOTEN1 0x20
-#define FLOPPY_DOR_MOTEN2 0x40
-#define FLOPPY_DOR_MOTEN3 0x80
-// Preset values to activate drive select and motor enable for each drive
-#define FLOPPY_DOR_DRV0 0x1C
-#define FLOPPY_DOR_DRV1 0x2D
-#define FLOPPY_DOR_DRV2 0x4E
-#define FLOPPY_DOR_DRV3 0x8F
-
-#define FLOPPY_MSR_FDD0BSY 0x01
-#define FLOPPY_MSR_FDD1BSY 0x02
-#define FLOPPY_MSR_FDD2BSY 0x04
-#define FLOPPY_MSR_FDD3BSY 0x08
-#define FLOPPY_MSR_FDCBSY 0x10
-#define FLOPPY_MSR_MODE 0x20 // 0 in DMA mode, 1 in PIO mode
-#define FLOPPY_MSR_DIO 0x40  // 0 FDC is expecting data from the CPU, 1 if FDC has data for CPU
-#define FLOPPY_MSR_RQM 0x80  // 0 Data register not ready, 1 data register ready
-
-#define FLOPPY_CCR_DRTESEL0 0x01
-#define FLOPPY_CCR_DRTESEL1 0x02
-
-#define FLOPPY_MT 0x80  // Multi-track selector. The controller treats 2 tracks (on side 0 and side 1) as a single track instead
-#define FLOPPY_MFM 0x40 // 1 Means this disk is double density (double sided??)
-#define FLOPPY_SK 0x20  // Skip flag. Skips sectors containing deleted data automatically for us :)
-
-#define SR0_OKAY (0x00) << 6
-#define SR0_ABORMAL_TERMINATION (0x01) << 6
-#define SR0_INVALID_CMD (0x02) << 6
-#define SR0_ABNORMAL_TERM_POLL (0x03) << 6
-
-#define FLOPPY_DMA_CHANNEL 2 // All FDCs are DMA channel 2
-#define IRQ_FLOPPY_DRIVE 6
-
-NonnullRefPtr<FloppyDiskDevice> FloppyDiskDevice::create(DriveType type)
-{
-    return adopt(*new FloppyDiskDevice(type));
-}
-
-const char* FloppyDiskDevice::class_name() const
-{
-    if (m_controller_version == 0x90)
-        return "Intel 82078 Floppy Disk Controller";
-    else if (m_controller_version == 0x80)
-        return "NEC uPD765";
-
-    return "Generic Floppy Disk Controller";
-}
-
-FloppyDiskDevice::FloppyDiskDevice(FloppyDiskDevice::DriveType type)
-    : IRQHandler(IRQ_FLOPPY_DRIVE)
-    , BlockDevice(89, (type == FloppyDiskDevice::DriveType::Master) ? 0 : 1, BYTES_PER_SECTOR)
-    , m_io_base_addr((type == FloppyDiskDevice::DriveType::Master) ? 0x3F0 : 0x370)
-{
-    initialize();
-}
-
-FloppyDiskDevice::~FloppyDiskDevice()
-{
-}
-
-bool FloppyDiskDevice::read_blocks(unsigned index, u16 count, u8* data)
-{
-    return read_sectors_with_dma(index, count, data);
-}
-
-bool FloppyDiskDevice::write_blocks(unsigned index, u16 count, const u8* data)
-{
-    return write_sectors_with_dma(index, count, data);
-    ;
-}
-
-bool FloppyDiskDevice::read_sectors_with_dma(u16 lba, u16 count, u8* outbuf)
-{
-    LOCKER(m_lock); // Acquire lock
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: read_sectors_with_dma lba = " << lba << " count = " << count;
-#endif
-
-    motor_enable(is_slave()); // Should I bother casting this?!
-    write_ccr(0);
-    recalibrate();
-
-    if (!seek(lba)) {
-        klog() << "fdc: failed to seek to lba = " << lba << "!";
-        return false;
-    }
-
-    // We have to wait for about 300ms for the drive to spin up, because of
-    // the inertia of the motor and diskette. This is only
-    // important on real hardware
-    // TODO: Fix this if you want to get it running on real hardware. This code doesn't allow
-    // time for the disk to spin up.
-
-    //u32 start = PIT::seconds_since_boot();
-    //while(start < PIT::seconds_since_boot() + 1)
-    //    ;
-
-    disable_irq();
-
-    IO::out8(0xA, FLOPPY_DMA_CHANNEL | 0x4); // Channel 2 SEL, MASK_ON = 1
-    IO::out8(0x0B, 0x56);                    // Begin DMA, Single Transfer, Increment, Auto, FDC -> RAM, Channel 2
-    IO::out8(0xA, 0x2);                      // Unmask channel 2. The transfer will now begin
-
-    // Translate the LBA address into something the FDC understands.
-    u16 cylinder = lba2cylinder(lba);
-    u16 head = lba2head(lba);
-    u16 sector = lba2sector(lba);
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: addr = 0x" << String::format("%x", lba * BYTES_PER_SECTOR) << " c = " << cylinder << " h = " << head << " s = " << sector;
-#endif
-
-    // Intel recommends 3 attempts for a read/write
-    for (int i = 0; i < 3; i++) {
-        // Now actually send the command to the drive. This is a big one!
-        send_byte(FLOPPY_MFM | FLOPPY_MT | FLOPPY_SK | static_cast<u8>(FloppyCommand::ReadData));
-        send_byte((head << 2) | is_slave());
-        send_byte(cylinder);
-        send_byte(head);
-        send_byte(sector);
-        send_byte(SECTORS_PER_CYLINDER >> 8); // Yikes!
-        send_byte(((sector + 1) >= SECTORS_PER_CYLINDER) ? SECTORS_PER_CYLINDER : sector + 1);
-        send_byte(0x1b); // GPL3 value. The Datasheet doesn't really specify the values for this properly...
-        send_byte(0xff);
-
-        enable_irq();
-
-        wait_for_irq(); // TODO: See if there was a lockup here via some "timeout counter"
-        m_interrupted = false;
-
-        // Flush FIFO
-        // Let's check the value of Status Register 1 to ensure that
-        // the command executed correctly
-        u8 cmd_st0 = read_byte();
-        if ((cmd_st0 & 0xc0) != 0) {
-            klog() << "fdc: read failed with error code (st0) 0x" << String::format("%x", cmd_st0 >> 6);
-            return false;
-        }
-
-        u8 cmd_st1 = read_byte();
-        if (cmd_st1 != 0) {
-            klog() << "fdc: read failed with error code (st1) 0x" << String::format("%x", cmd_st1);
-            return false;
-        }
-
-        read_byte();
-        u8 cyl = read_byte();
-        read_byte();
-        read_byte();
-        read_byte();
-
-        if (cyl != cylinder) {
-#ifdef FLOPPY_DEBUG
-            klog() << "fdc: cyl != cylinder (cyl = " << cyl << " cylinder = " << cylinder << ")! Retrying...";
-#endif
-            continue;
-        }
-
-        // Let the controller know we handled the interrupt
-        send_byte(FloppyCommand::SenseInterrupt);
-        u8 st0 = read_byte();
-        u8 pcn = read_byte();
-        static_cast<void>(st0);
-        static_cast<void>(pcn);
-
-        memcpy(outbuf, m_dma_buffer_page->paddr().as_ptr(), 512 * count);
-
-        return true;
-    }
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: out of read attempts (check your hardware maybe!?)";
-#endif
-    return false;
-}
-
-bool FloppyDiskDevice::write_sectors_with_dma(u16 lba, u16 count, const u8* inbuf)
-{
-    LOCKER(m_lock); // Acquire lock
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: write_sectors_with_dma lba = " << lba << " count = " << count;
-#endif
-
-    motor_enable(is_slave() ? 1 : 0); // Should I bother casting this?!
-    write_ccr(0);
-    recalibrate(); // Recalibrate the drive
-
-    if (!seek(lba)) {
-        klog() << "fdc: failed to seek to lba = " << lba << "!";
-        return false;
-    }
-
-    // We have to wait for about 300ms for the drive to spin up, because of
-    // the inertia of the motor and diskette.
-    // TODO: Fix this abomination please!
-    //u32 start = PIT::seconds_since_boot();
-    //while(start < PIT::seconds_since_boot() + 1)
-    //    ;
-
-    disable_irq();
-
-    IO::out8(0xA, FLOPPY_DMA_CHANNEL | 0x4); // Channel 2 SEL, MASK_ON = 1
-    IO::out8(0x0B, 0x5A);                    // Begin DMA, Single Transfer, Increment, Auto, RAM -> FDC, Channel 2
-    IO::out8(0xA, 0x2);                      // Unmask channel 2. The transfer will now begin
-
-    u16 cylinder = lba2cylinder(lba);
-    u16 head = lba2head(lba);
-    u16 sector = lba2sector(lba);
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: addr = 0x" << String::format("%x", lba * BYTES_PER_SECTOR) << " c = " << cylinder << " h = " << head << " s = " << sector;
-#endif
-
-    for (int i = 0; i < 3; i++) {
-        // Now actually send the command to the drive. This is a big one!
-        send_byte(FLOPPY_MFM | FLOPPY_MT | static_cast<u8>(FloppyCommand::WriteData));
-        send_byte(head << 2 | is_slave());
-        send_byte(cylinder);
-        send_byte(head);
-        send_byte(sector);
-        send_byte(SECTORS_PER_CYLINDER >> 8); // Yikes!
-        send_byte((sector + 1) >= SECTORS_PER_CYLINDER ? SECTORS_PER_CYLINDER : sector + 1);
-        send_byte(0x1b); // GPL3 value. The Datasheet doesn't really specify the values for this properly...
-        send_byte(0xff);
-
-        enable_irq();
-
-        wait_for_irq(); // TODO: See if there was a lockup here via some "timeout counter"
-        m_interrupted = false;
-
-        // Flush FIFO
-        u8 cmd_st0 = read_byte();
-        if ((cmd_st0 & 0xc0) != 0) {
-            klog() << "fdc: write failed! Error code 0x" << String::format("%x", cmd_st0 >> 6);
-            return false;
-        }
-
-        u8 cmd_st1 = read_byte();
-        if (cmd_st1 != 0) {
-            klog() << "fdc: write failed with error code (st1) 0x" << String::format("%x", cmd_st1);
-            return false;
-        }
-
-        read_byte();
-        u8 cyl = read_byte();
-        read_byte();
-        read_byte();
-        read_byte();
-
-        if (cyl != cylinder) {
-#ifdef FLOPPY_DEBUG
-            klog() << "fdc: cyl != cylinder (cyl = " << cyl << " cylinder = " << cylinder << ")! Retrying...";
-#endif
-            continue;
-        }
-
-        // Let the controller know we handled the interrupt
-        send_byte(FloppyCommand::SenseInterrupt);
-        u8 st0 = read_byte();
-        u8 pcn = read_byte();
-        static_cast<void>(st0);
-        static_cast<void>(pcn);
-
-        memcpy(m_dma_buffer_page->paddr().as_ptr(), inbuf, 512 * count);
-
-        return true;
-    }
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: out of read attempts (check your hardware maybe!?)";
-#endif
-    return false;
-}
-
-bool FloppyDiskDevice::wait_for_irq()
-{
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: Waiting for interrupt...";
-#endif
-
-    while (!m_interrupted) {
-        Scheduler::yield();
-    }
-
-    memory_barrier();
-    return true;
-}
-
-void FloppyDiskDevice::handle_irq(const RegisterState&)
-{
-    // The only thing we need to do is acknowledge the IRQ happened
-    m_interrupted = true;
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: Received IRQ!";
-#endif
-}
-
-void FloppyDiskDevice::send_byte(u8 value) const
-{
-    for (int i = 0; i < 1024; i++) {
-        if (read_msr() & FLOPPY_MSR_RQM) {
-            IO::out8(m_io_base_addr + FLOPPY_FIFO, value);
-            return;
-        }
-    }
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: FIFO write timed out!";
-#endif
-}
-
-void FloppyDiskDevice::send_byte(FloppyCommand value) const
-{
-    for (int i = 0; i < 1024; i++) {
-        if (read_msr() & FLOPPY_MSR_RQM) {
-            IO::out8(m_io_base_addr + FLOPPY_FIFO, static_cast<u8>(value));
-            return;
-        }
-    }
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: FIFO write timed out!";
-#endif
-}
-
-u8 FloppyDiskDevice::read_byte() const
-{
-    for (int i = 0; i < 1024; i++) {
-        if (read_msr() & (FLOPPY_MSR_RQM | FLOPPY_MSR_DIO)) {
-            return IO::in8(m_io_base_addr + FLOPPY_FIFO);
-        }
-    }
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: FIFO read timed out!";
-#endif
-
-    return 0xff;
-}
-
-void FloppyDiskDevice::write_dor(u8 value) const
-{
-    IO::out8(m_io_base_addr + FLOPPY_DOR, value);
-}
-
-void FloppyDiskDevice::write_ccr(u8 value) const
-{
-    IO::out8(m_io_base_addr + FLOPPY_CCR, value);
-}
-
-u8 FloppyDiskDevice::read_msr() const
-{
-    return IO::in8(m_io_base_addr + FLOPPY_MSR);
-}
-
-void FloppyDiskDevice::motor_enable(bool slave) const
-{
-    u8 val = slave ? 0x2D : 0x1C;
-    write_dor(val);
-}
-
-bool FloppyDiskDevice::is_busy() const
-{
-    return read_msr() & FLOPPY_MSR;
-}
-
-bool FloppyDiskDevice::recalibrate()
-{
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: recalibrating drive...";
-#endif
-
-    u8 slave = is_slave();
-    motor_enable(slave);
-
-    for (int i = 0; i < 16; i++) {
-        send_byte(FloppyCommand::Recalibrate);
-        send_byte(slave);
-        wait_for_irq();
-        m_interrupted = false;
-
-        send_byte(FloppyCommand::SenseInterrupt);
-        u8 st0 = read_byte();
-        u8 pcn = read_byte();
-        static_cast<void>(st0);
-
-        if (pcn == 0)
-            return true;
-    }
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: failed to calibrate drive (check your hardware!)";
-#endif
-    return false;
-}
-
-bool FloppyDiskDevice::seek(u16 lba)
-{
-    u8 head = lba2head(lba) & 0x01;
-    u8 cylinder = lba2cylinder(lba) & 0xff;
-    u8 slave = is_slave();
-
-    // First, we need to enable the correct drive motor
-    motor_enable(slave);
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: seeking to cylinder " << cylinder << " on side " << head << " on drive " << slave;
-#endif
-
-    // Try at most 5 times to seek to the desired cylinder
-    for (int attempt = 0; attempt < 5; attempt++) {
-        send_byte(FloppyCommand::Seek);
-        send_byte((head << 2) | slave);
-        send_byte(cylinder);
-        wait_for_irq();
-        m_interrupted = false;
-
-        send_byte(FloppyCommand::SenseInterrupt);
-        u8 st0 = read_byte();
-        u8 pcn = read_byte();
-
-        if ((st0 >> 5) != 1 || pcn != cylinder || (st0 & 0x01)) {
-#ifdef FLOPPY_DEBUG
-            klog() << "fdc: failed to seek to cylinder " << cylinder << " on attempt " << attempt << "!";
-#endif
-            continue;
-        }
-
-        return true;
-    }
-
-    klog() << "fdc: failed to seek after 3 attempts! Aborting...";
-    return false;
-}
-
-// This is following Intel's datasheet for the 82077, page 41
-void FloppyDiskDevice::initialize()
-{
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: m_io_base = 0x" << String::format("%x", m_io_base_addr) << " IRQn = " << IRQ_FLOPPY_DRIVE;
-#endif
-
-    enable_irq();
-
-    // Get the version of the Floppy Disk Controller
-    send_byte(FloppyCommand::Version);
-    m_controller_version = read_byte();
-    klog() << "fdc: Version = 0x" << String::format("%x", m_controller_version);
-
-    // Reset
-    write_dor(0);
-    write_dor(FLOPPY_DOR_RESET | FLOPPY_DOR_DMAGATE);
-
-    write_ccr(0);
-    wait_for_irq();
-    m_interrupted = false;
-
-    // "If (and only if) drive polling mode is turned on, send 4 Sense Interrupt commands (required). "
-    // Sorry OSDev, but the Intel Manual states otherwise. This ALWAYS needs to be performed.
-    for (int i = 0; i < 4; i++) {
-        send_byte(FloppyCommand::SenseInterrupt);
-        u8 sr0 = read_byte();
-        u8 trk = read_byte();
-
-        klog() << "sr0 = 0x" << String::format("%x", sr0) << ", cyl = 0x" << String::format("%x", trk);
-    }
-
-    // This is hardcoded for a 3.5" floppy disk drive
-    send_byte(FloppyCommand::Specify);
-    send_byte(0x08); // (SRT << 4) | HUT
-    send_byte(0x0A); // (HLT << 1) | NDMA
-
-    // Allocate a buffer page for us to read into. This only needs to be one sector in size.
-    m_dma_buffer_page = MM.allocate_supervisor_physical_page();
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: allocated supervisor page at paddr 0x", String::format("%x", m_dma_buffer_page->paddr());
-#endif
-
-    // Now, let's initialise channel 2 of the DMA controller!
-    // This only needs to be done here, then we can just change the direction of
-    // the transfer
-    IO::out8(0xA, FLOPPY_DMA_CHANNEL | 0x4); // Channel 2 SEL, MASK_ON = 1
-
-    IO::out8(0xC, 0xFF); // Reset Master Flip Flop
-
-    // Set the buffer page address (the lower 16-bits)
-    IO::out8(0x4, m_dma_buffer_page->paddr().get() & 0xff);
-    IO::out8(0x4, (m_dma_buffer_page->paddr().get() >> 8) & 0xff);
-
-    IO::out8(0xC, 0xFF); // Reset Master Flip Flop again
-
-    IO::out8(0x05, (SECTORS_PER_CYLINDER * BYTES_PER_SECTOR) & 0xff);
-    IO::out8(0x05, (SECTORS_PER_CYLINDER * BYTES_PER_SECTOR) >> 8);
-    IO::out8(0x81, (m_dma_buffer_page->paddr().get() >> 16) & 0xff); // Supervisor page could be a 24-bit address, so set the External Page R/W register
-
-    IO::out8(0xA, 0x2); // Unmask Channel 2
-
-#ifdef FLOPPY_DEBUG
-    klog() << "fdc: fd" << (is_slave() ? 1 : 0) << " initialised succesfully!";
-#endif
-}
-
-}

Kernel/Devices/FloppyDiskDevice.h

@@ -1,224 +0,0 @@
-/*
- * Copyright (c) 2019-2020, Jesse Buhagiar <jooster669@gmail.com>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright notice, this
- *    list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright notice,
- *    this list of conditions and the following disclaimer in the documentation
- *    and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-//
-// Intel 82078 Floppy Disk controller driver
-// Datasheet: https://wiki.qemu.org/images/f/f0/29047403.pdf
-//
-// The Intel 82078 is a 44-pin package, CHMOS Single Chip Floppy Disk Controller found commonly
-// on later PCs in the mid to late 90s. It supports a multitude of floppy drives found in computers
-// at the time, up to and including 2.8MB ED Floppy Disks and is software compatible with previous FDCs.
-// Drive in this case refers to the actual drive where the media is inserted and a disk is the actual
-// magnetic floppy disk media. This controller is emulated by QEMU.
-//
-// Certain terminology exists in the code of this driver that may be confusing, being that there
-// is a lot of code and documentation online that is seemingly conflicting. I've used terms found
-// directly in the datasheet however for the sake of completeness I'll explain them here:
-//
-//      - Cylinder: One full circular 'slice' of the floppy disk. It contains 18 sectors
-//                  on a 3.5" floppy disk. It is also known as a 'track'. There are
-//                  80 tracks on a single side of a floppy disk.
-//      - Sector:   One 512 byte chunk of a track.
-//      - Head:     The read write arm found inside the drive itself. On a double sided
-//                  floppy disk drive, there are two, one for the top tracks of the disk
-//                  and the other for the bottom tracks.
-//      - CHS:      Cylinder, Head, Sector. The addressing type this floppy controller
-//                  uses to address the disk geometry.
-//
-// A normal PC System usually contains one or two floppy drives. This controller contains the
-// ability to control up to four drives with the one controller, however it is very rare for
-// most systems to contain this amount of drives.
-//
-// The basic operation of the drive involves reseting the drive in hardware, then sending command
-// bytes to the FIFO, allowing the command to execute, then flushing the FIFO by reading `n` bytes
-// from it. Most commands are multi-parameter and multi-result, so it's best to consult the datasheet
-// from page 23. It is recommended that a SENSE command is performed to retrieve valubable interrupt
-// information about the performed action.
-//
-// Reseting the controller involves the following:
-//      - Acquire the version ID of the controller.
-//      - Reset the DOR register
-//      - Deassert software reset bit in the DOR register and assert the DMAGATE pin to initialize DMA mode
-//      - Program the Configuration Control Register (CCR) for 3.5" 1.44MB diskettes
-//      - Send a SPECIFY command to specify more drive information. Refer to the datasheet
-//
-// The drive (being mapped to the controller) will then be in a state that will accept the correct media.
-// The DMA controller is also set up here, which is on channel 2. This only needs to be done once, the
-// read and write commands can toggle the appropriate bits themselves to allow a specific transfer direction.
-//
-// Recalibrating the drive refers to the act of resetting the head of the drive back to track/cylinder 0. It
-// is essentially the same as a seek, however returning the drive to a known position. For the sake of brevity,
-// only the recalibrate sequence will be described.
-//
-//      - Enable the drive and it's motor (all drive motors are manually enabled by us!).
-//      - Issue a recalibrate or a seek command
-//      - Wait for interrupt
-//      - Issue a SENSE command, letting the drive know we handled the interrupt
-//      - Flush the FIFO and check the cylinder value to ensure we are at the correct spot.
-//
-// Once this has been completed, the drive will either be at the desired position or back at cylinder 0.
-//
-// To perform a READ or a WRITE of the diskette inserted, the following actions must be taken:
-//
-//      -The drive and it's motor must be enabled
-//      -The data rate must be set via CCR
-//      -The drive must be then recalibrated to ensure the head has not drifted.
-//      -A wait of 500ms or greater must occur to allow the drive to spin up from inertia.
-//      -The DMA direction of the transfer is then configured.
-//      -The READ or WRITE command is issued to the controller.
-//      -A timeout counter is started. This is only for real hardware and is currently not implemented.
-//      -Read the result bytes.
-//      -Attempt to READ or WRITE to the disk. Intel recommends doing this a max of 3 times before failing.
-//
-//
-//
-#pragma once
-
-#include <AK/RefPtr.h>
-#include <Kernel/Devices/BlockDevice.h>
-#include <Kernel/Interrupts/IRQHandler.h>
-#include <Kernel/Lock.h>
-#include <Kernel/VM/PhysicalPage.h>
-#include <LibBareMetal/Memory/PhysicalAddress.h>
-
-namespace Kernel {
-
-struct FloppyControllerCommand {
-    u8 cmd;         // Command to send to the controller
-    u8 numParams;   // Number of parameters to send to the drive
-    u8 numReturned; // Number of values we expect to be returned by the command
-    u8* params;
-    u8* result;
-};
-
-//
-// NOTE: This class only supports 3.5" 1.44MB floppy disks!
-// Any other type of drive will be ignored
-//
-// Also not that the floppy disk controller is set up to be in PS/2 mode, which
-// uses the Intel 82077A controller. More about this controller can
-// be found here: http://www.buchty.net/casio/files/82077.pdf
-//
-class FloppyDiskDevice final
-    : public IRQHandler
-    , public BlockDevice {
-    AK_MAKE_ETERNAL
-
-    static constexpr u8 SECTORS_PER_CYLINDER = 18;
-    static constexpr u8 CYLINDERS_PER_HEAD = 80;
-    static constexpr u16 BYTES_PER_SECTOR = 512;
-
-public:
-    //
-    // Is this floppy drive the master or the slave on the controller??
-    //
-    enum class DriveType : u8 {
-        Master,
-        Slave
-    };
-
-private:
-    // Floppy commands
-    enum class FloppyCommand : u8 {
-        ReadTrack = 0x02,
-        Specify = 0x03,
-        CheckStatus = 0x04,
-        WriteData = 0x05,
-        ReadData = 0x06,
-        Recalibrate = 0x07,
-        SenseInterrupt = 0x08,
-        WriteDeletedData = 0x09,
-        ReadDeletedData = 0x0C,
-        FormatTrack = 0x0D,
-        Seek = 0x0F,
-        Version = 0x10,
-        Verify = 0x16,
-    };
-
-public:
-    static NonnullRefPtr<FloppyDiskDevice> create(DriveType);
-    virtual ~FloppyDiskDevice() override;
-
-    // ^DiskDevice
-    virtual bool read_blocks(unsigned index, u16 count, u8*) override;
-    virtual bool write_blocks(unsigned index, u16 count, const u8*) override;
-
-    // ^BlockDevice
-    virtual ssize_t read(FileDescription&, u8*, ssize_t) override { return 0; }
-    virtual bool can_read(const FileDescription&) const override { return true; }
-    virtual ssize_t write(FileDescription&, const u8*, ssize_t) override { return 0; }
-    virtual bool can_write(const FileDescription&) const override { return true; }
-
-    virtual const char* purpose() const override { return "Floppy Disk Controller"; }
-
-protected:
-    explicit FloppyDiskDevice(DriveType);
-
-private:
-    // ^IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
-
-    // ^DiskDevice
-    virtual const char* class_name() const override;
-
-    // Helper functions
-    inline u16 lba2head(u16 lba) const { return (lba % (SECTORS_PER_CYLINDER * 2)) / SECTORS_PER_CYLINDER; } // Convert an LBA into a head value
-    inline u16 lba2cylinder(u16 lba) const { return lba / (2 * SECTORS_PER_CYLINDER); }                      // Convert an LBA into a cylinder value
-    inline u16 lba2sector(u16 lba) const { return ((lba % SECTORS_PER_CYLINDER) + 1); }                      // Convert an LBA into a sector value
-
-    void initialize();
-    bool read_sectors_with_dma(u16, u16, u8*);
-    bool write_sectors_with_dma(u16, u16, const u8*);
-    bool wait_for_irq();
-
-    bool is_busy() const;
-    bool seek(u16);
-    bool recalibrate();
-
-    void send_byte(u8) const;
-    void send_byte(FloppyCommand) const;
-
-    void write_dor(u8) const;
-    void write_ccr(u8) const;
-    void motor_enable(bool) const;
-    void configure_drive(u8, u8, u8) const;
-
-    u8 read_byte() const;
-    u8 read_msr() const;
-
-    bool is_slave() const { return m_drive_type == DriveType::Slave; }
-
-    Lock m_lock { "FloppyDiskDevice" };
-    u16 m_io_base_addr { 0 };
-    volatile bool m_interrupted { false };
-
-    DriveType m_drive_type { DriveType::Master };
-    RefPtr<PhysicalPage> m_dma_buffer_page;
-
-    u8 m_controller_version { 0 };
-};
-
-}

Kernel/Makefile

@@ -37,7 +37,6 @@ OBJS = \
     Devices/DebugLogDevice.o \
     Devices/Device.o \
     Devices/DiskPartition.o \
-    Devices/FloppyDiskDevice.o \
     Devices/FullDevice.o \
     Devices/GPTPartitionTable.o \
     Devices/EBRPartitionTable.o \

Kernel/init.cpp

@@ -40,7 +40,6 @@
 #include <Kernel/Devices/DebugLogDevice.h>
 #include <Kernel/Devices/DiskPartition.h>
 #include <Kernel/Devices/EBRPartitionTable.h>
-#include <Kernel/Devices/FloppyDiskDevice.h>
 #include <Kernel/Devices/FullDevice.h>
 #include <Kernel/Devices/GPTPartitionTable.h>
 #include <Kernel/Devices/KeyboardDevice.h>
@@ -310,24 +309,6 @@ void init_stage2()
     load_ksyms();
     dbg() << "Loaded ksyms";
 
-    // Now, detect whether or not there are actually any floppy disks attached to the system
-    u8 detect = CMOS::read(0x10);
-    RefPtr<FloppyDiskDevice> fd0;
-    RefPtr<FloppyDiskDevice> fd1;
-    if ((detect >> 4) & 0x4) {
-        fd0 = FloppyDiskDevice::create(FloppyDiskDevice::DriveType::Master);
-        klog() << "fd0 is 1.44MB floppy drive";
-    } else {
-        klog() << "fd0 type unsupported! Type == 0x", String::format("%x", detect >> 4);
-    }
-
-    if (detect & 0x0f) {
-        fd1 = FloppyDiskDevice::create(FloppyDiskDevice::DriveType::Slave);
-        klog() << "fd1 is 1.44MB floppy drive";
-    } else {
-        klog() << "fd1 type unsupported! Type == 0x", String::format("%x", detect & 0x0f);
-    }
-
     int error;
 
     // SystemServer will start WindowServer, which will be doing graphics.