multiboot: parse mmap blocks

Signed-off-by: Tianhao Wang <shrik3@mailbox.org>

2 files changed, 56 insertions, 1 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 25a8768..cd5cd7c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -34,6 +34,8 @@ pub extern "C" fn _entry() -> ! {
 	let mmap = unsafe { mbi.get_mmap() }.unwrap();
 	println!("memory: {:#X?}", mem);
 	println!("mmap (start): {:#X?}", mmap);
+
+	multiboot::_test_mmap();
 	interrupt::init();
 	pic_8259::allow(PicDeviceInt::KEYBOARD);
 	interrupt::interrupt_enable();
diff --git a/src/machine/multiboot.rs b/src/machine/multiboot.rs
index c420c2b..885e104 100644
--- a/src/machine/multiboot.rs
+++ b/src/machine/multiboot.rs
@@ -1,4 +1,6 @@
 use crate::io::*;
+use core::fmt;
+use core::mem::size_of;
 use lazy_static::lazy_static;
 // provide functions to parse information provided by grub multiboot
 // see docs/multiboot.txt
@@ -24,7 +26,6 @@ pub fn check() -> bool {
 
 #[repr(C)]
 #[repr(packed)]
-#[derive(Debug)]
 pub struct MultibootMmap {
 	pub size: u32,
 	pub addr: u64,
@@ -32,6 +33,41 @@ pub struct MultibootMmap {
 	pub mtype: u32,
 }
 
+impl fmt::Debug for MultibootMmap {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		let addr = self.addr;
+		let len = self.len;
+		let mtype = self.mtype;
+		write!(
+			f,
+			"[{}] @ {:#X} + {:#X}",
+			match mtype {
+				MultibootMmap::MTYPE_RAM => "GOOD",
+				MultibootMmap::MTYPE_RAM_RES => "RESV",
+				MultibootMmap::MTYPE_ACPI => "ACPI",
+				MultibootMmap::MTYPE_RAM_NVS => "NVS ",
+				MultibootMmap::MTYPE_RAM_DEFECT => "BAD ",
+				_ => "UNKN",
+			},
+			addr,
+			len,
+		)
+	}
+}
+
+impl MultibootMmap {
+	/// avaialble ram
+	pub const MTYPE_RAM: u32 = 1;
+	/// reserved ram
+	pub const MTYPE_RAM_RES: u32 = 2;
+	/// usable memory holding ACPI info
+	pub const MTYPE_ACPI: u32 = 3;
+	/// WHAT IS THIS 4???
+	pub const MTYPE_RAM_NVS: u32 = 4;
+	/// defective RAM
+	pub const MTYPE_RAM_DEFECT: u32 = 5;
+}
+
 #[repr(C)]
 #[repr(packed)]
 #[derive(Debug, Clone, Copy)]
@@ -40,6 +76,23 @@ pub struct MultibootInfoMmap {
 	pub mmap_addr: u32,
 }
 
+pub fn _test_mmap() {
+	let mmapinfo = unsafe { MBOOTINFO.get_mmap() }.unwrap();
+	let buf_start = mmapinfo.mmap_addr;
+	let buf_len = mmapinfo.mmap_length;
+	let buf_end = buf_start + buf_len;
+	let mut curr = buf_start as u64;
+	loop {
+		if curr >= buf_end as u64 {
+			break;
+		}
+		let mblock = unsafe { &*(curr as *const MultibootMmap) };
+		curr += mblock.size as u64;
+		curr += 4; // mmap.size does not include the the size itself
+		println!("mem block {:#X?}", mblock);
+	}
+}
+
 #[repr(C)]
 #[repr(packed)]
 #[derive(Debug, Clone, Copy)]