feat: acpi, apic, apic timer

src/arch/x86_64/io_apic.rs

@@ -0,0 +1,213 @@
+use crate::{
+    memory::{
+        AddressSpace, CachePolicy, FrameAllocator, PagePermissions, PhysicalAddr, VirtualAddr,
+    },
+    platform::acpi::{InterruptPolarity, IoApicInfo, TriggerMode},
+    println,
+};
+
+const IOREGSEL: usize = 0x00;
+const IOWIN: usize = 0x10;
+
+const IOAPIC_ID: u8 = 0x00;
+const IOAPIC_VERSION: u8 = 0x01;
+const IOAPIC_REDIRECTION_BASE: u8 = 0x10;
+
+const MASKED: u32 = 1 << 16;
+
+pub const IOAPIC_VIRTUAL_ADDRESS: VirtualAddr = VirtualAddr::new(0xFFFF_FFFD_1000_0000);
+
+#[derive(Debug)]
+pub enum IoApicError {
+    IdMismatch { expected: u8, actual: u8 },
+    GsiOutsideRange,
+    FailedToMapIoApic,
+    InvalidRedirectionIndex,
+}
+
+pub struct RedirectionConfig {
+    pub vector: u8,
+    pub destination: u8,
+    pub polarity: InterruptPolarity,
+    pub trigger: TriggerMode,
+}
+
+#[derive(Debug)]
+pub struct IoApic {
+    base: VirtualAddr,
+    global_interrupt_base: u32,
+    redirection_entry_count: u32,
+}
+
+impl IoApic {
+    pub fn new(
+        expected_id: u8,
+        physical_address: PhysicalAddr,
+        global_interrupt_base: u32,
+        virtual_address: VirtualAddr,
+        allocator: &mut FrameAllocator,
+        address_space: &mut AddressSpace,
+    ) -> Result<Self, IoApicError> {
+        address_space
+            .map(
+                physical_address,
+                virtual_address,
+                PagePermissions::new(true, false, false),
+                allocator,
+                CachePolicy::Uncacheable,
+            )
+            .map_err(|_| IoApicError::FailedToMapIoApic)?;
+
+        let mut io_apic = Self {
+            base: virtual_address,
+            global_interrupt_base: global_interrupt_base,
+            redirection_entry_count: 0,
+        };
+
+        let version = io_apic.read(IOAPIC_VERSION);
+        io_apic.redirection_entry_count = ((version >> 16) & 0xFF) + 1;
+
+        let id = ((io_apic.read(IOAPIC_ID) >> 24) & 0xF) as u8;
+        if id != expected_id {
+            return Err(IoApicError::IdMismatch {
+                expected: expected_id,
+                actual: id,
+            });
+        }
+        println!("IOAPIC ID: {:#X}", id);
+        println!("IOAPIC version: {:#X}", version & 0xFF);
+
+        println!(
+            "IOAPIC redirection entry count: {:#X}",
+            io_apic.redirection_entry_count
+        );
+
+        Ok(io_apic)
+    }
+
+    fn read(&mut self, register: u8) -> u32 {
+        unsafe {
+            self.base
+                .as_mut_ptr::<u32>()
+                .write_volatile(register as u32);
+
+            self.base
+                .as_ptr::<u8>()
+                .add(IOWIN)
+                .cast::<u32>()
+                .read_volatile()
+        }
+    }
+
+    fn write(&mut self, register: u8, value: u32) {
+        unsafe {
+            self.base
+                .as_mut_ptr::<u32>()
+                .write_volatile(register as u32);
+
+            self.base
+                .as_mut_ptr::<u8>()
+                .add(IOWIN)
+                .cast::<u32>()
+                .write_volatile(value);
+        }
+    }
+
+    fn redirection_index(&self, gsi: u32) -> Result<u32, IoApicError> {
+        let index = gsi
+            .checked_sub(self.global_interrupt_base)
+            .ok_or(IoApicError::GsiOutsideRange)?;
+
+        if index >= self.redirection_entry_count {
+            return Err(IoApicError::GsiOutsideRange);
+        }
+
+        Ok(index)
+    }
+
+    pub fn handles_gsi(&mut self, gsi: u32) -> bool {
+        match gsi.checked_sub(self.global_interrupt_base) {
+            Some(index) => index < self.redirection_entry_count,
+            None => false,
+        }
+    }
+
+    fn read_redirection(&mut self, gsi: u32) -> Result<u64, IoApicError> {
+        let index = self.redirection_index(gsi)?;
+        let register = u8::try_from(IOAPIC_REDIRECTION_BASE as u32 + index * 2)
+            .map_err(|_| IoApicError::InvalidRedirectionIndex)?;
+
+        let low = self.read(register);
+        let high = self.read(register + 1);
+
+        Ok((high as u64) << 32 | low as u64)
+    }
+
+    fn redirection_registers(&mut self, gsi: u32) -> Result<(u8, u8), IoApicError> {
+        let index = self.redirection_index(gsi)?;
+        let low_register = u8::try_from(IOAPIC_REDIRECTION_BASE as u32 + index * 2)
+            .map_err(|_| IoApicError::InvalidRedirectionIndex)?;
+
+        let high_register = u8::try_from(IOAPIC_REDIRECTION_BASE as u32 + index * 2 + 1)
+            .map_err(|_| IoApicError::InvalidRedirectionIndex)?;
+
+        Ok((low_register, high_register))
+    }
+
+    pub fn configure_masked(
+        &mut self,
+        gsi: u32,
+        config: RedirectionConfig,
+    ) -> Result<(), IoApicError> {
+        let mut entry = config.vector as u64;
+
+        match config.polarity {
+            InterruptPolarity::ActiveHigh => {
+                entry |= 0 << 13;
+            }
+            InterruptPolarity::ActiveLow => {
+                entry |= 1 << 13;
+            }
+        }
+
+        match config.trigger {
+            TriggerMode::Edge => {
+                entry |= 0 << 15;
+            }
+            TriggerMode::Level => {
+                entry |= 1 << 15;
+            }
+        }
+
+        entry |= 1 << 16;
+        entry |= (config.destination as u64) << 56;
+
+        let (low_register, high_register) = self.redirection_registers(gsi)?;
+
+        let old_low = self.read(low_register);
+        self.write(low_register, old_low | MASKED);
+
+        self.write(high_register, (entry >> 32) as u32);
+        self.write(low_register, entry as u32 | MASKED);
+
+        Ok(())
+    }
+
+    pub fn unmask(&mut self, gsi: u32) -> Result<(), IoApicError> {
+        let (low_register, _) = self.redirection_registers(gsi)?;
+        let low = self.read(low_register);
+
+        self.write(low_register, low & !MASKED);
+
+        Ok(())
+    }
+
+    pub fn mask(&mut self, gsi: u32) -> Result<(), IoApicError> {
+        let (low_register, _) = self.redirection_registers(gsi)?;
+        let low = self.read(low_register);
+
+        self.write(low_register, low | MASKED);
+
+        Ok(())
+    }
+}