1 files changed, 127 insertions, 0 deletions
diff --git a/jslinux-2019-12-21/tinyemu-2019-12-21/simplefb.c b/jslinux-2019-12-21/tinyemu-2019-12-21/simplefb.c
new file mode 100644
index 0000000..5664cea
--- /dev/null
+++ b/jslinux-2019-12-21/tinyemu-2019-12-21/simplefb.c
@@ -0,0 +1,127 @@
+/*
+ * Simple frame buffer
+ * 
+ * Copyright (c) 2017 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <inttypes.h>
+#include <assert.h>
+
+#include "cutils.h"
+#include "iomem.h"
+#include "virtio.h"
+#include "machine.h"
+
+//#define DEBUG_VBE
+
+#define FB_ALLOC_ALIGN 65536
+
+struct SimpleFBState {
+    FBDevice *fb_dev;
+    int fb_page_count;
+    PhysMemoryRange *mem_range;
+};
+
+#define MAX_MERGE_DISTANCE 3
+
+void simplefb_refresh(FBDevice *fb_dev,
+                      SimpleFBDrawFunc *redraw_func, void *opaque,
+                      PhysMemoryRange *mem_range,
+                      int fb_page_count)
+{
+    const uint32_t *dirty_bits;
+    uint32_t dirty_val;
+    int y0, y1, page_y0, page_y1, byte_pos, page_index, bit_pos;
+
+    dirty_bits = phys_mem_get_dirty_bits(mem_range);
+    
+    page_index = 0;
+    y0 = y1 = 0;
+    while (page_index < fb_page_count) {
+        dirty_val = dirty_bits[page_index >> 5];
+        if (dirty_val != 0) {
+            bit_pos = 0;
+            while (dirty_val != 0) {
+                while (((dirty_val >> bit_pos) & 1) == 0)
+                    bit_pos++;
+                dirty_val &= ~(1 << bit_pos);
+
+                byte_pos = (page_index + bit_pos) * DEVRAM_PAGE_SIZE;
+                page_y0 = byte_pos / fb_dev->stride;
+                page_y1 = ((byte_pos + DEVRAM_PAGE_SIZE - 1) / fb_dev->stride) + 1;
+                page_y1 = min_int(page_y1, fb_dev->height);
+                if (y0 == y1) {
+                    y0 = page_y0;
+                    y1 = page_y1;
+                } else if (page_y0 <= (y1 + MAX_MERGE_DISTANCE)) {
+                    /* union with current region */
+                    y1 = page_y1;
+                } else {
+                    /* flush */
+                    redraw_func(fb_dev, opaque,
+                                0, y0, fb_dev->width, y1 - y0);
+                    y0 = page_y0;
+                    y1 = page_y1;
+                }
+            }
+        }
+        page_index += 32;
+    }
+
+    if (y0 != y1) {
+        redraw_func(fb_dev, opaque,
+                    0, y0, fb_dev->width, y1 - y0);
+    }
+}
+
+static void simplefb_refresh1(FBDevice *fb_dev,
+                              SimpleFBDrawFunc *redraw_func, void *opaque)
+{
+    SimpleFBState *s = fb_dev->device_opaque;
+    simplefb_refresh(fb_dev, redraw_func, opaque, s->mem_range,
+                     s->fb_page_count);
+}
+
+SimpleFBState *simplefb_init(PhysMemoryMap *map, uint64_t phys_addr,
+                             FBDevice *fb_dev, int width, int height)
+{
+    SimpleFBState *s;
+    
+    s = mallocz(sizeof(*s));
+    s->fb_dev = fb_dev;
+
+    fb_dev->width = width;
+    fb_dev->height = height;
+    fb_dev->stride = width * 4;
+    fb_dev->fb_size = (height * fb_dev->stride + FB_ALLOC_ALIGN - 1) & ~(FB_ALLOC_ALIGN - 1);
+    s->fb_page_count = fb_dev->fb_size >> DEVRAM_PAGE_SIZE_LOG2;
+
+    s->mem_range = cpu_register_ram(map, phys_addr, fb_dev->fb_size,
+                                    DEVRAM_FLAG_DIRTY_BITS);
+    
+    fb_dev->fb_data = s->mem_range->phys_mem;
+    fb_dev->device_opaque = s;
+    fb_dev->refresh = simplefb_refresh1;
+    return s;
+}