115 lines
3.9 KiB
ArmAsm
115 lines
3.9 KiB
ArmAsm
/*
|
|
* 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
|