| Julius Werner | 94f8907 | 2017-07-31 18:15:11 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved. |
| 3 | * |
| 4 | * SPDX-License-Identifier: BSD-3-Clause |
| 5 | */ |
| 6 | #include <asm_macros.S> |
| 7 | |
| 8 | /* |
| 9 | * This is the common console core code for the deprecated single-console API. |
| 10 | * New platforms should set MULTI_CONSOLE_API=1 and not use this file. |
| 11 | */ |
| 12 | |
| 13 | .globl console_init |
| 14 | .globl console_uninit |
| 15 | .globl console_putc |
| 16 | .globl console_getc |
| 17 | .globl console_flush |
| 18 | |
| 19 | /* |
| 20 | * The console base is in the data section and not in .bss |
| 21 | * even though it is zero-init. In particular, this allows |
| 22 | * the console functions to start using this variable before |
| 23 | * the runtime memory is initialized for images which do not |
| 24 | * need to copy the .data section from ROM to RAM. |
| 25 | */ |
| 26 | .section .data.console_base ; .align 3 |
| 27 | console_base: .quad 0x0 |
| 28 | |
| 29 | /* ----------------------------------------------- |
| 30 | * int console_init(uintptr_t base_addr, |
| 31 | * unsigned int uart_clk, unsigned int baud_rate) |
| 32 | * Function to initialize the console without a |
| 33 | * C Runtime to print debug information. It saves |
| 34 | * the console base to the data section. |
| 35 | * In: x0 - console base address |
| 36 | * w1 - Uart clock in Hz |
| 37 | * w2 - Baud rate |
| 38 | * out: return 1 on success else 0 on error |
| 39 | * Clobber list : x1 - x4 |
| 40 | * ----------------------------------------------- |
| 41 | */ |
| 42 | func console_init |
| 43 | /* Check the input base address */ |
| 44 | cbz x0, init_fail |
| 45 | adrp x3, console_base |
| 46 | str x0, [x3, :lo12:console_base] |
| 47 | b console_core_init |
| 48 | init_fail: |
| 49 | ret |
| 50 | endfunc console_init |
| 51 | |
| 52 | /* ----------------------------------------------- |
| 53 | * void console_uninit(void) |
| 54 | * Function to finish the use of console driver. |
| 55 | * It sets the console_base as NULL so that any |
| 56 | * further invocation of `console_putc` or |
| 57 | * `console_getc` APIs would return error. |
| 58 | * ----------------------------------------------- |
| 59 | */ |
| 60 | func console_uninit |
| 61 | mov x0, #0 |
| 62 | adrp x3, console_base |
| 63 | str x0, [x3, :lo12:console_base] |
| 64 | ret |
| 65 | endfunc console_uninit |
| 66 | |
| 67 | /* --------------------------------------------- |
| 68 | * int console_putc(int c) |
| 69 | * Function to output a character over the |
| 70 | * console. It returns the character printed on |
| 71 | * success or -1 on error. |
| 72 | * In : x0 - character to be printed |
| 73 | * Out : return -1 on error else return character. |
| 74 | * Clobber list : x1, x2 |
| 75 | * --------------------------------------------- |
| 76 | */ |
| 77 | func console_putc |
| 78 | adrp x2, console_base |
| 79 | ldr x1, [x2, :lo12:console_base] |
| 80 | b console_core_putc |
| 81 | endfunc console_putc |
| 82 | |
| 83 | /* --------------------------------------------- |
| 84 | * int console_getc(void) |
| 85 | * Function to get a character from the console. |
| 86 | * It returns the character grabbed on success |
| 87 | * or -1 on error. |
| 88 | * Clobber list : x0, x1 |
| 89 | * --------------------------------------------- |
| 90 | */ |
| 91 | func console_getc |
| 92 | adrp x1, console_base |
| 93 | ldr x0, [x1, :lo12:console_base] |
| 94 | b console_core_getc |
| 95 | endfunc console_getc |
| 96 | |
| 97 | /* --------------------------------------------- |
| 98 | * int console_flush(void) |
| 99 | * Function to force a write of all buffered |
| 100 | * data that hasn't been output. It returns 0 |
| 101 | * upon successful completion, otherwise it |
| 102 | * returns -1. |
| 103 | * Clobber list : x0, x1 |
| 104 | * --------------------------------------------- |
| 105 | */ |
| 106 | func console_flush |
| 107 | adrp x1, console_base |
| 108 | ldr x0, [x1, :lo12:console_base] |
| 109 | b console_core_flush |
| 110 | endfunc console_flush |