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/*
* xen/arch/arm/arm32/debug-8250.inc
*
* 8250 specific debug code
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <xen/8250-uart.h>
/* 8250 UART wait UART to be ready to transmit
* rb: register which contains the UART base address
* rc: scratch register */
.macro early_uart_ready rb rc
1:
ldr \rc, [\rb, #(UART_LSR << EARLY_UART_REG_SHIFT)] /* Read LSR */
tst \rc, #UART_LSR_THRE /* Check Xmit holding register flag */
beq 1b /* Wait for the UART to be ready */
.endm
/* 8250 UART transmit character
* rb: register which contains the UART base address
* rt: register which contains the character to transmit */
.macro early_uart_transmit rb rt
str \rt, [\rb, #UART_THR] /* Write Transmit buffer */
.endm
/*
* Local variables:
* mode: ASM
* indent-tabs-mode: nil
* End:
*/
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