[lib][gfx] Add mono 1bpp support

[lib][font] Use mono 1bpp byte-span drawing, where available

- Adds 1bpp rendering function, and accompanying implementations of putpixel, copyrect, fillrect.

- libgfx now calls arch_clean_cache_range() conditionally, to avoid crashes on architectures lacking cache support.

- Includes changes made by scripts/codestyle

Author: jrac

lib/font/font.c

@@ -16,9 +16,9 @@
  * @ingroup graphics
  */
 
-#include <lk/debug.h>
-#include <lib/gfx.h>
 #include <lib/font.h>
+#include <lib/gfx.h>
+#include <lk/debug.h>
 
 #include "font.h"
 
@@ -28,19 +28,47 @@
  * @ingroup graphics
  */
 void font_draw_char(gfx_surface *surface, unsigned char c, int x, int y, uint32_t color) {
-    uint i,j;
+    uint i, j;
     uint line;
 
-    // draw this char into a buffer
+    // 1bpp batched per-byte, for performance boost
+    if (surface->format == GFX_FORMAT_MONO_1 && surface->spanmono1) {
+        uint32_t c1 = surface->translate_color ? surface->translate_color(color) : color;
+        gfx_span_op op = (c1 != 0) ? GFX_SPAN_SET : GFX_SPAN_CLR;
+
+        for (i = 0; i < FONT_Y; i++) {
+            line = FONT[(c * FONT_Y) + i];
+
+            for (j = 0; j < FONT_X;) {
+                if ((line & 0x1) == 0) {
+                    line >>= 1;
+                    j++;
+                    continue;
+                }
+
+                uint start = j;
+                do {
+                    line >>= 1;
+                    j++;
+                } while (j < FONT_X && (line & 0x1));
+
+                surface->spanmono1(surface, (x + start), (y + i), (j - start), op);
+            }
+        }
+
+        gfx_flush_rows(surface, y, (y + FONT_Y));
+        return;
+    }
+
+    // Per-pixel default
     for (i = 0; i < FONT_Y; i++) {
-        line = FONT[c * FONT_Y + i];
+        line = FONT[(c * FONT_Y) + i];
         for (j = 0; j < FONT_X; j++) {
-            if (line & 0x1)
-                gfx_putpixel(surface, x + j, y + i, color);
+            if (line & 0x1) {
+                gfx_putpixel(surface, (x + j), (y + i), color);
+            }
             line = line >> 1;
         }
     }
-    gfx_flush_rows(surface, y, y + FONT_Y);
+    gfx_flush_rows(surface, y, (y + FONT_Y));
 }
-
-