1/* 2 * xen/arch/arm/arm64/debug-mvebu.inc 3 * 4 * MVEBU specific debug code. 5 * 6 * Copyright (c) 2018, Amit Singh Tomar <amittomer25@gmail.com>. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms and conditions of the GNU General Public 10 * License, version 2, as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public 18 * License along with this program; If not, see <http://www.gnu.org/licenses/>. 19 */ 20 21#define UART_STATUS_REG 0x0c 22#define UART_TX_REG 0x04 23 24/* 25 * MVEBU UART wait UART to be ready to transmit 26 * xb: register which contains the UART base address 27 * c: scratch register 28 */ 29.macro early_uart_ready xb c 301: 31 ldrh w\c, [\xb, #UART_STATUS_REG] /* status register */ 32 tst w\c, #(1 << 11) /* Check TXFIFO FULL bit */ 33 b.ne 1b /* Wait for the UART to be ready */ 34.endm 35 36/* 37 * MVEBU UART transmit character 38 * xb: register which contains the UART base address 39 * wt: register which contains the character to transmit 40 */ 41.macro early_uart_transmit xb wt 42 strb \wt, [\xb, #UART_TX_REG] 43.endm 44 45/* 46 * Local variables: 47 * mode: ASM 48 * indent-tabs-mode: nil 49 * End: 50 */ 51