uniphier_console.S 1.41 KB
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/*
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 * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
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 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <asm_macros.S>
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#include <drivers/console.h>
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#include "uniphier_console.h"
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/*
 * In: w0 - character to be printed
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 *     x1 - pointer to console structure
 * Out: return the character written (always succeeds)
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 * Clobber: x2
 */
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	.globl	uniphier_console_putc
func uniphier_console_putc
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	ldr	x1, [x1, #CONSOLE_T_BASE]
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	/* Wait until the transmitter FIFO gets empty */
0:	ldr	w2, [x1, #UNIPHIER_UART_LSR]
	tbz	w2, #UNIPHIER_UART_LSR_THRE_BIT, 0b

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	str	w0, [x1, #UNIPHIER_UART_TX]
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	ret
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endfunc uniphier_console_putc
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/*
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 * In: x0 - pointer to console structure
 * Out: return the character read, or ERROR_NO_PENDING_CHAR if no character
	is available
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 * Clobber: x1
 */
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	.globl	uniphier_console_getc
func uniphier_console_getc
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	ldr	x0, [x0, #CONSOLE_T_BASE]
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	ldr	w1, [x0, #UNIPHIER_UART_LSR]
	tbz	w1, #UNIPHIER_UART_LSR_DR_BIT, 0f
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	ldr	w0, [x0, #UNIPHIER_UART_RX]
	ret
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0:	mov	w0, #ERROR_NO_PENDING_CHAR
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	ret
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endfunc uniphier_console_getc
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/*
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 * In: x0 - pointer to console structure
 * Out: return 0 (always succeeds)
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 * Clobber: x1
 */
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	.global uniphier_console_flush
func uniphier_console_flush
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	ldr	x0, [x0, #CONSOLE_T_BASE]
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	/* wait until the transmitter gets empty */
0:	ldr	w1, [x0, #UNIPHIER_UART_LSR]
	tbz	w1, #UNIPHIER_UART_LSR_TEMT_BIT, 0b

	mov	w0, #0
	ret
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endfunc uniphier_console_flush