Merge pull request #113 from ethindp/master

Add the boot graphics resource table as specified in SEC. 5.2.22 of the ACPI specification v. 6.4

acpi/src/bgrt.rs

@@ -0,0 +1,63 @@
+use crate::{sdt::SdtHeader, AcpiTable};
+use bit_field::BitField;
+
+/// The BGRT table contains information about a boot graphic that was displayed
+/// by firmware.
+#[repr(C, packed)]
+#[derive(Clone, Copy)]
+pub struct Bgrt {
+    header: SdtHeader,
+    pub version: u16,
+    status: u8,
+    image_type: u8,
+    pub image_address: u64,
+    image_offset_x: u32,
+    image_offset_y: u32,
+}
+
+impl AcpiTable for Bgrt {
+    fn header(&self) -> &SdtHeader {
+        &self.header
+    }
+}
+
+impl Bgrt {
+    pub fn image_type(&self) -> ImageType {
+        let img_type = self.image_type;
+        match img_type {
+            0 => ImageType::Bitmap,
+            _ => ImageType::Reserved,
+        }
+    }
+
+    /// Gets the orientation offset of the image.
+    /// Degrees are clockwise from the images default orientation.
+    pub fn orientation_offset(&self) -> u16 {
+        let status = self.status;
+        match status.get_bits(1..3) {
+            0 => 0,
+            1 => 90,
+            2 => 180,
+            3 => 270,
+            _ => unreachable!(), // will never happen
+        }
+    }
+
+    pub fn was_displayed(&self) -> bool {
+        let status = self.status;
+        status.get_bit(0)
+    }
+
+    pub fn image_offset(&self) -> (u32, u32) {
+        let x = self.image_offset_x;
+        let y = self.image_offset_y;
+        (x, y)
+    }
+}
+
+#[repr(u8)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub enum ImageType {
+    Bitmap,
+    Reserved,
+}

acpi/src/lib.rs

@@ -55,6 +55,7 @@ extern crate alloc;
 #[cfg(test)]
 extern crate std;
 
+pub mod bgrt;
 pub mod fadt;
 pub mod hpet;
 pub mod madt;