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/*
* Copyright (c) 2014, STMicroelectronics International N.V.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 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 <platform_config.h>
#include <asm.S>
#include <kernel/unwind.h>
#define ASC_BAUDRATE 0x00
#define ASC_TXBUFFER 0x04
#define ASC_RXBUFFER 0x08
#define ASC_CONTROL 0x0c
#define ASC_INTENABLE 0x10
#define ASC_STATUS 0x14
#define ASC_GUARDTIME 0x18
#define ASC_TIMEOUT 0x1c
#define ASC_TXRESET 0x20
#define ASC_RXRESET 0x24
#define ASC_RETRIES 0x28
.section .text.asc
/*
* void __asc_flush(vaddr_t base)
*
* Clobbers r0-r3
*/
FUNC __asc_flush , :
UNWIND( .fnstart)
ADD r3, r0, #ASC_STATUS
flush_wait:
LDR r1, [r3]
ANDS r1, r1, #0x02 /* AND TX FIFO EMPTY flag */
BEQ flush_wait /* ANDS should have set Z bit if zero */
LDR r0, =0
BX lr
UNWIND( .fnend)
END_FUNC __asc_flush
/*
* int __asc_xmit_char(char p, vaddr_t base) - Transmit a single character.
*
* R0 is the 1-byte character to be transmited
* R1 is the base address of the uart
* Clobbers r0-r3
*/
FUNC __asc_xmit_char , :
UNWIND( .fnstart)
ADD r2, r1, #ASC_TXBUFFER
ADD r3, r1, #ASC_STATUS
/* Output byte */
/* Spin until TX FIFO ready */
__asc_char_crwait:
LDR r1, [r3]
ANDS r1, r1, #0x04 /* AND TX FIFO HALF EMPTY flag */
BEQ __asc_char_crwait /* ANDS should have set Z bit if zero */
MOVS r1, r0
LDR r0, =0xFF
AND r1, r1, r0
BEQ __asc_char_exit
CMP r1, #0xa /* r1 == \n (line feed) ? */
BNE __asc_char_notlf
/* Transmit character extra carriage return for each line feed */
LDR r1, =0x0d
STR r1, [r2]
LDR r1, =0x0a /* replace line feed */
__asc_char_notlf:
/* Transmit character */
STR r1, [r2]
__asc_char_exit:
LDR r0, =0
BX lr
UNWIND( .fnend)
END_FUNC __asc_xmit_char
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