Feat: lab 3 w/o adv 2

kernel/include/uart.h

@@ -0,0 +1,25 @@
+#pragma once
+
+#include <stddef.h>
+#include <ringbuffer.h>
+
+#define UART_BUFLEN 0x800
+
+void uart_init(void);
+char uart_getc(void);
+void uart_puts(const char *s);
+void uart_hex(uint64_t d);
+
+void uart_irq_handler(void);
+
+size_t uart_putb_sync(const uint8_t *bytes, size_t len);
+size_t uart_getb_sync(uint8_t *bytes, size_t len);
+
+size_t uart_putb_async(const uint8_t *bytes, size_t len);
+size_t uart_getb_async(uint8_t *bytes, size_t len);
+
+extern size_t (*uart_putb)(const uint8_t *bytes, size_t len);
+extern size_t (*uart_getb)(uint8_t *bytes, size_t len);
+extern int is_uart_inited;
+
+extern ringbuffer_t *uart_readbuf;