1/* 2 * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 7 * Redistributions of source code must retain the above copyright notice, this 8 * list of conditions and the following disclaimer. 9 * 10 * Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 14 * Neither the name of ARM nor the names of its contributors may be used 15 * to endorse or promote products derived from this software without specific 16 * prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28 * POSSIBILITY OF SUCH DAMAGE. 29 */ 30#include <arch.h> 31#include <asm_macros.S> 32#include <pl011.h> 33 34/* 35 * Pull in generic functions to provide backwards compatibility for 36 * platform makefiles 37 */ 38#include "../../../console/aarch32/console.S" 39 40 .globl console_core_init 41 .globl console_core_putc 42 .globl console_core_getc 43 44 45 /* ----------------------------------------------- 46 * int console_core_init(uintptr_t base_addr, 47 * unsigned int uart_clk, unsigned int baud_rate) 48 * Function to initialize the console without a 49 * C Runtime to print debug information. This 50 * function will be accessed by console_init and 51 * crash reporting. 52 * In: r0 - console base address 53 * r1 - Uart clock in Hz 54 * r2 - Baud rate 55 * Out: return 1 on success else 0 on error 56 * Clobber list : r1, r2, r3 57 * ----------------------------------------------- 58 */ 59func console_core_init 60 /* Check the input base address */ 61 cmp r0, #0 62 beq core_init_fail 63#if !PL011_GENERIC_UART 64 /* Check baud rate and uart clock for sanity */ 65 cmp r1, #0 66 beq core_init_fail 67 cmp r2, #0 68 beq core_init_fail 69 /* Disable the UART before initialization */ 70 ldr r3, [r0, #UARTCR] 71 bic r3, r3, #PL011_UARTCR_UARTEN 72 str r3, [r0, #UARTCR] 73 /* Program the baudrate */ 74 /* Divisor = (Uart clock * 4) / baudrate */ 75 lsl r1, r1, #2 76 udiv r2, r1, r2 77 /* IBRD = Divisor >> 6 */ 78 lsr r1, r2, #6 79 /* Write the IBRD */ 80 str r1, [r0, #UARTIBRD] 81 /* FBRD = Divisor & 0x3F */ 82 and r1, r2, #0x3f 83 /* Write the FBRD */ 84 str r1, [r0, #UARTFBRD] 85 mov r1, #PL011_LINE_CONTROL 86 str r1, [r0, #UARTLCR_H] 87 /* Clear any pending errors */ 88 mov r1, #0 89 str r1, [r0, #UARTECR] 90 /* Enable tx, rx, and uart overall */ 91 ldr r1, =(PL011_UARTCR_RXE | PL011_UARTCR_TXE | PL011_UARTCR_UARTEN) 92 str r1, [r0, #UARTCR] 93#endif 94 mov r0, #1 95 bx lr 96core_init_fail: 97 mov r0, #0 98 bx lr 99endfunc console_core_init 100 101 /* -------------------------------------------------------- 102 * int console_core_putc(int c, uintptr_t base_addr) 103 * Function to output a character over the console. It 104 * returns the character printed on success or -1 on error. 105 * In : r0 - character to be printed 106 * r1 - console base address 107 * Out : return -1 on error else return character. 108 * Clobber list : r2 109 * -------------------------------------------------------- 110 */ 111func console_core_putc 112 /* Check the input parameter */ 113 cmp r1, #0 114 beq putc_error 115 /* Prepend '\r' to '\n' */ 116 cmp r0, #0xA 117 bne 2f 1181: 119 /* Check if the transmit FIFO is full */ 120 ldr r2, [r1, #UARTFR] 121 tst r2, #PL011_UARTFR_TXFF 122 bne 1b 123 mov r2, #0xD 124 str r2, [r1, #UARTDR] 1252: 126 /* Check if the transmit FIFO is full */ 127 ldr r2, [r1, #UARTFR] 128 tst r2, #PL011_UARTFR_TXFF 129 bne 2b 130 str r0, [r1, #UARTDR] 131 bx lr 132putc_error: 133 mov r0, #-1 134 bx lr 135endfunc console_core_putc 136 137 /* --------------------------------------------- 138 * int console_core_getc(uintptr_t base_addr) 139 * Function to get a character from the console. 140 * It returns the character grabbed on success 141 * or -1 on error. 142 * In : r0 - console base address 143 * Clobber list : r0, r1 144 * --------------------------------------------- 145 */ 146func console_core_getc 147 cmp r0, #0 148 beq getc_error 1491: 150 /* Check if the receive FIFO is empty */ 151 ldr r1, [r0, #UARTFR] 152 tst r1, #PL011_UARTFR_RXFE 153 bne 1b 154 ldr r1, [r0, #UARTDR] 155 mov r0, r1 156 bx lr 157getc_error: 158 mov r0, #-1 159 bx lr 160endfunc console_core_getc 161