1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * arch/arm/include/debug/8250.S
4 *
5 * Copyright (C) 1994-2013 Russell King
6 */
7#include <linux/serial_reg.h>
8
9 .macro addruart, rp, rv, tmp
10 ldr \rp, =CONFIG_DEBUG_UART_PHYS
11 ldr \rv, =CONFIG_DEBUG_UART_VIRT
12 .endm
13
14#ifdef CONFIG_DEBUG_UART_8250_WORD
15 .macro store, rd, rx:vararg
16 ARM_BE8(rev \rd, \rd)
17 str \rd, \rx
18 ARM_BE8(rev \rd, \rd)
19 .endm
20
21 .macro load, rd, rx:vararg
22 ldr \rd, \rx
23 ARM_BE8(rev \rd, \rd)
24 .endm
25#else
26 .macro store, rd, rx:vararg
27 strb \rd, \rx
28 .endm
29
30 .macro load, rd, rx:vararg
31 ldrb \rd, \rx
32 .endm
33#endif
34
35#define UART_SHIFT CONFIG_DEBUG_UART_8250_SHIFT
36
37 .macro senduart,rd,rx
38 store \rd, [\rx, #UART_TX << UART_SHIFT]
39 .endm
40
41 .macro busyuart,rd,rx
421002: load \rd, [\rx, #UART_LSR << UART_SHIFT]
43 and \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
44 teq \rd, #UART_LSR_TEMT | UART_LSR_THRE
45 bne 1002b
46 .endm
47
48 .macro waituarttxrdy,rd,rx
49 .endm
50
51 .macro waituartcts,rd,rx
521001: load \rd, [\rx, #UART_MSR << UART_SHIFT]
53 tst \rd, #UART_MSR_CTS
54 beq 1001b
55 .endm
56

source code of linux/arch/arm/include/debug/8250.S