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/*
* Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <asm_macros.S>
.globl console_init
.globl console_uninit
.globl console_putc
.globl console_getc
/*
* The console base is in the data section and not in .bss
* even though it is zero-init. In particular, this allows
* the console functions to start using this variable before
* the runtime memory is initialized for images which do not
* need to copy the .data section from ROM to RAM.
*/
.section .data.console_base ; .align 2
console_base: .word 0x0
/* -----------------------------------------------
* int console_init(uintptr_t base_addr,
* unsigned int uart_clk, unsigned int baud_rate)
* Function to initialize the console without a
* C Runtime to print debug information. It saves
* the console base to the data section.
* In: r0 - console base address
* r1 - Uart clock in Hz
* r2 - Baud rate
* out: return 1 on success else 0 on error
* Clobber list : r1 - r3
* -----------------------------------------------
*/
func console_init
/* Check the input base address */
cmp r0, #0
beq init_fail
ldr r3, =console_base
str r0, [r3]
b console_core_init
init_fail:
bx lr
endfunc console_init
/* -----------------------------------------------
* void console_uninit(void)
* Function to finish the use of console driver.
* It sets the console_base as NULL so that any
* further invocation of `console_putc` or
* `console_getc` APIs would return error.
* -----------------------------------------------
*/
func console_uninit
mov r0, #0
ldr r3, =console_base
str r0, [r3]
bx lr
endfunc console_uninit
/* ---------------------------------------------
* int console_putc(int c)
* Function to output a character over the
* console. It returns the character printed on
* success or -1 on error.
* In : r0 - character to be printed
* Out : return -1 on error else return character.
* Clobber list : r1, r2
* ---------------------------------------------
*/
func console_putc
ldr r2, =console_base
ldr r1, [r2]
b console_core_putc
endfunc console_putc
/* ---------------------------------------------
* int console_getc(void)
* Function to get a character from the console.
* It returns the character grabbed on success
* or -1 on error.
* Clobber list : r0, r1
* ---------------------------------------------
*/
func console_getc
ldr r1, =console_base
ldr r0, [r1]
b console_core_getc
endfunc console_getc
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