IDE: clean everything up

ableos/src/arch/x86_64/interrupts.rs

@@ -6,11 +6,7 @@
 
 use core::panic::PanicInfo;
 
-use crate::{
-    arch::gdt,
-    println,
-    rhai_shell::KEYBUFF,
-};
+use crate::{arch::gdt, println, rhai_shell::KEYBUFF};
 use cpuio::outb;
 use pic8259::ChainedPics;
 use qrcode::QrCode;

ableos/src/devices/pci/ide.rs

@@ -7,9 +7,9 @@
 use core::num::TryFromIntError;
 
 // FIXME: platform agnostic-ify these
-use x86_64::instructions::{port::Port, interrupts};
-use x86_64::structures::paging::{FrameAllocator, FrameDeallocator};
+use x86_64::instructions::{interrupts, port::Port};
 use x86_64::structures::paging::{mapper::MapToError, Mapper, Page, PhysFrame, Size4KiB};
+use x86_64::structures::paging::{FrameAllocator, FrameDeallocator};
 use x86_64::VirtAddr;
 
 use crate::arch::memory::BootInfoFrameAllocator;
@@ -21,6 +21,9 @@ use super::PciDeviceInfo;
 const PRDT_START: u64 = 0xffff_ffff_0000_0000;
 const BUFFER_START: u64 = 0xffff_ffff_0000_1000;
 
+/// ATA logical sector size, in bytes
+const SECTOR_SIZE: u16 = 512;
+
 /// Bus Master IDE Command
 const BMIC_OFFSET: u16 = 0;
 /// Bus Master IDE Status
@@ -251,7 +254,17 @@ impl PciIde {
         Ok(())
     }
 
-    pub fn read(&mut self) -> Result<(), TryFromIntError> {
+    pub fn read(
+        &mut self,
+        channel: Channel,
+        drive: Drive,
+        lba: u64,
+        sector_count: u16,
+    ) -> Result<Vec<u8>, TryFromIntError> {
+        // FIXME: make this an error
+        assert!(lba < 0xFFFFFFFFFFFF);
+        let byte_count = sector_count * SECTOR_SIZE;
+
         // prepare PRD table
         let prd = PRDT_START as *mut PhysRegionDescriptor;
         unsafe {
@@ -259,8 +272,7 @@ impl PciIde {
                 .start_address()
                 .as_u64()
                 .try_into()?;
-            // we want to read 512 bytes
-            (*prd).byte_count = 512;
+            (*prd).byte_count = byte_count;
             // this is the end of table
             (*prd).eot = 1 << 7;
             // this byte is reserved, we should probably set it to 0
@@ -268,40 +280,42 @@ impl PciIde {
         }
 
         unsafe {
-            self.load_prdt(Channel::Primary);
-            self.stop(Channel::Primary);
-            self.set_read(Channel::Primary);
-            self.clear_bmi_status(Channel::Primary);
-            select_drive(Drive::Master, Channel::Primary);
-            set_lba(Channel::Primary, 0, 1);
-            ata_send_command(CMD_READ_DMA_EXT, Channel::Primary);
-            self.start(Channel::Primary);
+            self.load_prdt(channel);
+            self.stop(channel);
+            self.set_read(channel);
+            self.clear_bmi_status(channel);
+            select_drive(drive, channel);
+            set_lba(channel, lba, sector_count);
+            ata_send_command(CMD_READ_DMA_EXT, channel);
+            self.start(channel);
+        }
 
-            loop {
-                let status = self.bmi_status(Channel::Primary);
-                trace!("read status: 0b{status:b}");
+        loop {
+            let status = unsafe { self.bmi_status(channel) };
 
-                // Bit 2 (INT) set?
-                if (status >> 2) & 1 == 1 {
-                    break;
-                }
-            }
-
-            // FIXME: error handling
-
-            // Stop DMA
-            self.stop(Channel::Primary);
-
-            // Clear the interrupt bit
-            self.clear_bmi_status(Channel::Primary);
-
-            for i in 0..512 {
-                let addr = (BUFFER_START + i) as *mut u8;
-                trace!("byte {i}: {}", *addr);
+            // Bit 2 (INT) set?
+            if (status >> 2) & 1 == 1 {
+                break;
             }
         }
 
-        Ok(())
+        // FIXME: error handling
+
+        unsafe {
+            // Stop DMA
+            self.stop(channel);
+
+            // Clear the interrupt bit
+            self.clear_bmi_status(channel);
+        }
+
+        let mut buffer = Vec::with_capacity(byte_count as usize);
+        for i in 0..512 {
+            let addr = (BUFFER_START + i) as *mut u8;
+            buffer.push(unsafe { *addr });
+        }
+
+        Ok(buffer)
     }
 
     pub fn device_info(&self) -> PciDeviceInfo {
@@ -512,7 +526,7 @@ struct IdeDevice {
 }
 
 #[derive(Copy, Clone, Debug)]
-enum Channel {
+pub enum Channel {
     Primary,
     Secondary,
 }
@@ -524,7 +538,7 @@ impl Channel {
 }
 
 #[derive(Copy, Clone, Debug)]
-enum Drive {
+pub enum Drive {
     Master,
     Slave,
 }

ableos/src/scratchpad.rs

@@ -6,6 +6,7 @@
 
 use crate::arch::drivers::sysinfo::master;
 use crate::arch::interrupts::{reset_pit_for_cpu, set_pit_2};
+use crate::devices::pci::ide::{Channel, Drive};
 use crate::devices::pci::{PciDevice, PCI_DEVICES};
 use crate::filesystem;
 use crate::filesystem::vfs::VFS;
@@ -113,7 +114,7 @@ pub fn scratchpad() {
         BANNER_WIDTH
     );
 
-    let piix_ide_device = {
+    let pci_ide_device = {
         let pci_devices = PCI_DEVICES.lock();
         pci_devices
             .iter()
@@ -127,10 +128,15 @@ pub fn scratchpad() {
             })
             .unwrap()
     };
-    let mut piix_ide_device = piix_ide_device.lock();
-    if let PciDevice::Ide(device) = &mut *piix_ide_device {
-        device.read().unwrap()
+
+    {
+        let mut pci_ide_device = pci_ide_device.lock();
+        if let PciDevice::Ide(device) = &mut *pci_ide_device {
+            let first_sector = device.read(Channel::Primary, Drive::Master, 0, 1).unwrap();
+            trace!("IDE Primary/Master sector 0: {first_sector:?}");
+        }
     }
+
     real_shell();
 }