1/* 2 * xen/arch/arm/arm64/debug-scif.inc 3 * 4 * SCIF specific debug code 5 * 6 * Oleksandr Tyshchenko <oleksandr.tyshchenko@globallogic.com> 7 * Iurii Konovalenko <iurii.konovalenko@globallogic.com> 8 * Iurii Mykhalskyi <iurii.mykhalskyi@globallogic.com> 9 * Copyright (C) 2014-2016, Globallogic. 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 */ 21 22#include <asm/scif-uart.h> 23 24/* 25 * SCIF 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, #SCIF_SCFSR] /* <- SCFSR (status register) */ 32 tst w\c, #SCFSR_TDFE /* Check TDFE bit */ 33 beq 1b /* Wait for the UART to be ready */ 34.endm 35 36/* 37 * SCIF 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, #SCIF_SCFTDR] /* -> SCFTDR (data register) */ 43 ldrh \wt, [\xb, #SCIF_SCFSR] /* <- SCFSR (status register) */ 44 and \wt, \wt, #(~(SCFSR_TEND | SCFSR_TDFE)) /* Clear TEND and TDFE bits */ 45 strh \wt, [\xb, #SCIF_SCFSR] /* -> SCFSR (status register) */ 46.endm 47 48/* 49 * Local variables: 50 * mode: ASM 51 * indent-tabs-mode: nil 52 * End: 53 */ 54