WIP: VESA driver. Make initfs generated by code

drivers/vesad/src/display.rs

@@ -0,0 +1,112 @@
+use std::cmp;
+
+use primitive::{fast_set, fast_set64, fast_copy64};
+
+static FONT: &'static [u8] = include_bytes!("../../../res/unifont.font");
+
+/// A display
+pub struct Display {
+    pub width: usize,
+    pub height: usize,
+    pub onscreen: &'static mut [u32],
+    pub offscreen: &'static mut [u32],
+}
+
+impl Display {
+    pub fn new(width: usize, height: usize, onscreen: &'static mut [u32], offscreen: &'static mut [u32]) -> Display {
+        Display {
+            width: width,
+            height: height,
+            onscreen: onscreen,
+            offscreen: offscreen,
+        }
+    }
+
+    /// Draw a rectangle
+    pub fn rect(&mut self, x: usize, y: usize, w: usize, h: usize, color: u32) {
+        let start_y = cmp::min(self.height - 1, y);
+        let end_y = cmp::min(self.height, y + h);
+
+        let start_x = cmp::min(self.width - 1, x);
+        let len = cmp::min(self.width, x + w) - start_x;
+
+        let mut offscreen_ptr = self.offscreen.as_mut_ptr() as usize;
+        let mut onscreen_ptr = self.onscreen.as_mut_ptr() as usize;
+
+        let stride = self.width * 4;
+
+        let offset = y * stride + start_x * 4;
+        offscreen_ptr += offset;
+        onscreen_ptr += offset;
+
+        let mut rows = end_y - start_y;
+        while rows > 0 {
+            unsafe {
+                fast_set(offscreen_ptr as *mut u32, color, len);
+                fast_set(onscreen_ptr as *mut u32, color, len);
+            }
+            offscreen_ptr += stride;
+            onscreen_ptr += stride;
+            rows -= 1;
+        }
+    }
+
+    /// Draw a character
+    fn char(&mut self, x: usize, y: usize, character: char, color: u32) {
+        if x + 8 <= self.width && y + 16 <= self.height {
+            let mut font_i = 16 * (character as usize);
+            let font_end = font_i + 16;
+            if font_end <= FONT.len() {
+                let mut offscreen_ptr = self.offscreen.as_mut_ptr() as usize;
+                let mut onscreen_ptr = self.onscreen.as_mut_ptr() as usize;
+
+                let stride = self.width * 4;
+
+                let offset = y * stride + x * 4;
+                offscreen_ptr += offset;
+                onscreen_ptr += offset;
+
+                while font_i < font_end {
+                    let mut row_data = FONT[font_i];
+                    let mut col = 8;
+                    while col > 0 {
+                        col -= 1;
+                        if row_data & 1 == 1 {
+                            unsafe {
+                                *((offscreen_ptr + col * 4) as *mut u32) = color;
+                            }
+                        }
+                        row_data = row_data >> 1;
+                    }
+
+                    unsafe {
+                        fast_copy64(onscreen_ptr as *mut u64, offscreen_ptr as *const u64, 4);
+                    }
+
+                    offscreen_ptr += stride;
+                    onscreen_ptr += stride;
+                    font_i += 1;
+                }
+            }
+        }
+    }
+
+    /// Scroll display
+    pub fn scroll(&mut self, rows: usize, color: u32) {
+        let data = (color as u64) << 32 | color as u64;
+
+        let width = self.width/2;
+        let height = self.height;
+        if rows > 0 && rows < height {
+            let off1 = rows * width;
+            let off2 = height * width - off1;
+            unsafe {
+                let data_ptr = self.offscreen.as_mut_ptr() as *mut u64;
+                fast_copy64(data_ptr, data_ptr.offset(off1 as isize), off2);
+                fast_set64(data_ptr.offset(off2 as isize), data, off1);
+
+                fast_copy64(self.onscreen.as_mut_ptr() as *mut u64, data_ptr, off1 + off2);
+            }
+        }
+    }
+}