rpi start. doesn't work

hw/mcu/broadcom/bcm2711/io.h

@@ -0,0 +1,13 @@
+// From: https://github.com/isometimes/rpi4-osdev/blob/master/part4-miniuart/io.h
+// CC-0 License
+
+void uart_init(void);
+void uart_writeText(const char *buffer);
+void uart_loadOutputFifo(void);
+unsigned char uart_readByte(void);
+unsigned int uart_isReadByteReady(void);
+void uart_writeByteBlocking(unsigned char ch);
+void uart_update(void);
+void gpio_setPinOutputBool(unsigned int pin_number, unsigned int onOrOff);
+void uart_writeByteBlockingActual(unsigned char ch);
+void gpio_initOutputPinWithPullNone(unsigned int pin_number);