/* * Copyright (C) 2018 bzt (bztsrc@github) * * 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 "uart.h" #include "mmu.h" #define KERNEL_UART0_DR ((volatile unsigned int*)0xFFFFFFFFFFE00000) #define KERNEL_UART0_FR ((volatile unsigned int*)0xFFFFFFFFFFE00018) void main() { char *s="Writing through MMIO mapped in higher half!\r\n"; // set up serial console uart_init(); // set up paging mmu_init(); // test mapping uart_puts("Writing through identity mapped MMIO.\n"); // test mapping while(*s) { /* wait until we can send */ do{asm volatile("nop");}while(*KERNEL_UART0_FR&0x20); /* write the character to the buffer */ *KERNEL_UART0_DR=*s++; } // echo everything back while(1) { uart_send(uart_getc()); } }