From e9d89576a371285e023fa76c90049adf575a8bab Mon Sep 17 00:00:00 2001
From: WangRunji <wangrunji0408@163.com>
Date: Sat, 7 Apr 2018 22:40:22 +0800
Subject: [PATCH] Port acpiinit()

---
 src/arch/x86_64/driver/acpi/mod.rs     | 53 +++++++++++++++++++++++---
 src/arch/x86_64/driver/acpi/structs.rs | 17 +++++++--
 src/lib.rs                             |  2 +-
 3 files changed, 63 insertions(+), 9 deletions(-)

diff --git a/src/arch/x86_64/driver/acpi/mod.rs b/src/arch/x86_64/driver/acpi/mod.rs
index e065a95..b286501 100644
--- a/src/arch/x86_64/driver/acpi/mod.rs
+++ b/src/arch/x86_64/driver/acpi/mod.rs
@@ -4,15 +4,58 @@ mod structs;
 use self::structs::*;
 
 /// See https://wiki.osdev.org/RSDP -- Detecting the RSDP
-pub fn find_rdsp() -> Option<*const rsdp> {
+pub fn find_rsdp() -> Option<&'static rsdp> {
 	use util::{Checkable, find_in_memory};
 	let ebda = unsafe { *(0x40E as *const u16) as usize } << 4;
 	debug!("EBDA at {:#x}", ebda);
+
+	macro_rules! return_if_find_in {
+		($begin:expr, $end:expr) => (
+			if let Some(addr) = unsafe{ find_in_memory::<rsdp>($begin, $end, 4) } {
+				return Some(unsafe{ &*(addr as *const rsdp) });
+			}
+		)
+	}
+	
 	if ebda != 0 {
-		if let Some(addr) = unsafe{ find_in_memory::<rsdp>(ebda as usize, 1024, 4) } {
-			return Some(addr as *const rsdp);
-		}
+		return_if_find_in!(ebda as usize, 1024);
 	}
-	unsafe{ find_in_memory::<rsdp>(0xE0000, 0x20000, 4).map(|addr| addr as *const rsdp) }
+	return_if_find_in!(0xE0000, 0x20000);
+	None
 } 
 
+#[cfg(target_arch="x86")]
+const PHYSICAL_MEMORY_LIMIT: u32 = 0x0E000000;
+#[cfg(target_arch="x86_64")]
+const PHYSICAL_MEMORY_LIMIT: u32 = 0x80000000;
+
+#[derive(Debug)]
+pub enum ACPI_Error {
+	NotMapped
+}
+
+pub fn init() -> Result<(), ACPI_Error> {
+	use core::mem::size_of;
+	use util::Checkable;
+	let rsdp = find_rsdp().expect("acpi: rsdp not found.");
+	if rsdp.RsdtPhysicalAddress > PHYSICAL_MEMORY_LIMIT {
+		return Err(ACPI_Error::NotMapped);
+	}
+	let rsdt = unsafe{ &*(rsdp.RsdtPhysicalAddress as *const rsdt) };
+	let entry_count = (rsdt.Header.Length as usize - size_of::<header>()) / 4;
+	let mut madt: Option<&'static madt> = None;
+	for i in 0 ..  entry_count {
+		let entry = unsafe{ rsdt.entry_at(i) };
+		if entry > PHYSICAL_MEMORY_LIMIT {
+			return Err(ACPI_Error::NotMapped);
+		}
+		let header = unsafe{ &*(entry as *const header) };
+		debug!("{:?}", header);
+		if &header.Signature == b"APIC" {
+			madt = Some(unsafe{ &*(entry as *const madt) });
+		}
+	}
+	debug!("{:?}", madt);
+	// return acpi_config_smp(madt);
+	Ok(())
+}
diff --git a/src/arch/x86_64/driver/acpi/structs.rs b/src/arch/x86_64/driver/acpi/structs.rs
index 96c55fb..51dd777 100644
--- a/src/arch/x86_64/driver/acpi/structs.rs
+++ b/src/arch/x86_64/driver/acpi/structs.rs
@@ -26,7 +26,7 @@ impl Checkable for rsdp {
 #[repr(C)]
 #[derive(Debug)]
 pub struct header {
-    pub Signature: [i8; 4],
+    pub Signature: [u8; 4],
     pub Length: u32,
     pub Revision: u8,
     pub Checksum: u8,
@@ -41,7 +41,13 @@ pub struct header {
 #[derive(Debug)]
 pub struct rsdt {
     pub Header: header,
-    pub TableOffsetEntry: [u32; 1],
+    TableOffsetEntry: [u32; 0],
+}
+
+impl rsdt {
+    pub unsafe fn entry_at(&self, id: usize) -> u32 {
+        *(self.TableOffsetEntry.as_ptr().offset(id as isize))
+    }
 }
 
 #[repr(C)]
@@ -50,9 +56,14 @@ pub struct madt {
     pub Header: header,
     pub Address: u32,
     pub Flags: u32,
+    Table: [u32; 0],
 }
 
-const MADT_SIGNATURE: [u8; 4] = *b"APIC";
+impl Checkable for madt {
+    fn check(&self) -> bool {
+        &self.Header.Signature == b"APIC"
+    }
+}
 
 #[repr(C)]
 #[derive(Debug)]
diff --git a/src/lib.rs b/src/lib.rs
index 3139708..968ae21 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -46,7 +46,7 @@ mod arch;
 pub extern "C" fn rust_main(multiboot_information_address: usize) {
     // ATTENTION: we have a very small stack and no guard page
     println!("MP = {:?}", arch::driver::mp::find_mp());
-    println!("RDSP = {:?}", arch::driver::acpi::find_rdsp());
+    arch::driver::acpi::init();
     loop {
         
     }