mirror of
https://github.com/rust-embedded/rust-raspberrypi-OS-tutorials.git
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58 lines
1.8 KiB
C
58 lines
1.8 KiB
C
/*
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* Copyright (C) 2018 bzt (bztsrc@github)
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*
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* Permission is hereby granted, free of charge, to any person
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* obtaining a copy of this software and associated documentation
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* files (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use, copy,
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* modify, merge, publish, distribute, sublicense, and/or sell copies
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* of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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* DEALINGS IN THE SOFTWARE.
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*
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*/
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#include "uart.h"
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#include "mmu.h"
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#define KERNEL_UART0_DR ((volatile unsigned int*)0xFFFFFFFFFFE00000)
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#define KERNEL_UART0_FR ((volatile unsigned int*)0xFFFFFFFFFFE00018)
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void main()
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{
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char *s="Writing through MMIO mapped in higher half!\r\n";
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// set up serial console
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uart_init();
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// set up paging
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mmu_init();
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// test mapping
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uart_puts("Writing through identity mapped MMIO.\n");
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// test mapping
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while(*s) {
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/* wait until we can send */
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do{asm volatile("nop");}while(*KERNEL_UART0_FR&0x20);
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/* write the character to the buffer */
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*KERNEL_UART0_DR=*s++;
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}
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// echo everything back
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while(1) {
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uart_send(uart_getc());
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}
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}
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