Implement 2D graphic API (#87)

* Implement 2D graphic library based on LittlevGL

* Add lvgl license file

samples/gui/wasm-runtime-wgl/src/platform/zephyr/iwasm_main.c

@@ -0,0 +1,181 @@
+/*
+ * Copyright (C) 2019 Intel Corporation.  All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "bh_platform.h"
+#include "runtime_lib.h"
+#include "native_interface.h"
+#include "app_manager_export.h"
+#include "board_config.h"
+#include "bh_common.h"
+#include "bh_queue.h"
+#include "bh_thread.h"
+#include "bh_memory.h"
+#include "runtime_sensor.h"
+#include "attr_container.h"
+#include "module_wasm_app.h"
+#include "wasm_export.h"
+#include "display.h"
+#include "lvgl.h"
+
+extern void * thread_timer_check(void *);
+extern void init_sensor_framework();
+extern int aee_host_msg_callback(void *msg, uint16_t msg_len);
+extern bool touchscreen_read(lv_indev_data_t * data);
+extern int ili9340_init();
+extern void xpt2046_init(void);
+extern void wgl_init();
+
+#include <zephyr.h>
+#include <uart.h>
+#include <device.h>
+
+int uart_char_cnt = 0;
+
+static void uart_irq_callback(struct device *dev)
+{
+    unsigned char ch;
+
+    while (uart_poll_in(dev, &ch) == 0) {
+        uart_char_cnt++;
+        aee_host_msg_callback(&ch, 1);
+    }
+}
+
+struct device *uart_dev = NULL;
+
+static bool host_init()
+{
+    uart_dev = device_get_binding(HOST_DEVICE_COMM_UART_NAME);
+    if (!uart_dev) {
+        printf("UART: Device driver not found.\n");
+        return false;
+    }
+    uart_irq_rx_enable(uart_dev);
+    uart_irq_callback_set(uart_dev, uart_irq_callback);
+    return true;
+}
+
+int host_send(void * ctx, const char *buf, int size)
+{
+    for (int i = 0; i < size; i++)
+        uart_poll_out(uart_dev, buf[i]);
+
+    return size;
+}
+
+void host_destroy()
+{
+}
+
+host_interface interface = {
+    .init = host_init,
+    .send = host_send,
+    .destroy = host_destroy
+};
+
+timer_ctx_t timer_ctx;
+
+static char global_heap_buf[270 * 1024] = { 0 };
+
+static uint8_t color_copy[320 * 10 * 3];
+
+static void display_flush(lv_disp_drv_t *disp_drv,
+                          const lv_area_t *area,
+                          lv_color_t *color)
+{
+    u16_t w = area->x2 - area->x1 + 1;
+    u16_t h = area->y2 - area->y1 + 1;
+    struct display_buffer_descriptor desc;
+    int i;
+    uint8_t *color_p = color_copy;
+
+    desc.buf_size = 3 * w * h;
+    desc.width = w;
+    desc.pitch = w;
+    desc.height = h;
+
+    for (i = 0; i < w * h; i++, color++) {
+        color_p[i * 3] = color->ch.red;
+        color_p[i * 3 + 1] = color->ch.green;
+        color_p[i * 3 + 2] = color->ch.blue;
+    }
+
+    display_write(NULL, area->x1, area->y1, &desc, (void *) color_p);
+
+    lv_disp_flush_ready(disp_drv); /* in v5.3 is lv_flush_ready */
+}
+
+static bool display_input_read(lv_indev_drv_t *indev_drv, lv_indev_data_t *data)
+{
+    return touchscreen_read(data);
+}
+
+/**
+ * Initialize the Hardware Abstraction Layer (HAL) for the Littlev graphics library
+ */
+static void hal_init(void)
+{
+    xpt2046_init();
+    ili9340_init();
+    display_blanking_off(NULL);
+
+    /*Create a display buffer*/
+    static lv_disp_buf_t disp_buf1;
+    static lv_color_t buf1_1[320*10];
+    lv_disp_buf_init(&disp_buf1, buf1_1, NULL, 320*10);
+
+    /*Create a display*/
+    lv_disp_drv_t disp_drv;
+    lv_disp_drv_init(&disp_drv);            /*Basic initialization*/
+    disp_drv.buffer = &disp_buf1;
+    disp_drv.flush_cb = display_flush;
+    //    disp_drv.hor_res = 200;
+    //    disp_drv.ver_res = 100;
+    lv_disp_drv_register(&disp_drv);
+
+    lv_indev_drv_t indev_drv;
+    lv_indev_drv_init(&indev_drv);          /*Basic initialization*/
+    indev_drv.type = LV_INDEV_TYPE_POINTER;
+    indev_drv.read_cb = display_input_read;
+    lv_indev_drv_register(&indev_drv);
+}
+
+int iwasm_main()
+{
+    host_init();
+
+    if (bh_memory_init_with_pool(global_heap_buf, sizeof(global_heap_buf))
+            != 0) {
+        printf("Init global heap failed.\n");
+        return -1;
+    }
+
+    if (vm_thread_sys_init() != 0) {
+        goto fail1;
+    }
+
+    wgl_init();
+    hal_init();
+
+    // timer manager
+    init_wasm_timer();
+
+    // TODO:
+    app_manager_startup(&interface);
+
+fail1:
+    bh_memory_destroy();
+    return -1;
+}