linux_dsm_epyc7002/arch/arm/include/debug/8250.S
Ben Dooks 6ef4e47926 ARM: debug: fix big endian operation for 8250 word mode
If the 8250 debug code is used in word mode on an big endian
host then the writes need to be change into little endian for
the bus.

Note, we have to re-convert the value back as the debug code
will inspect the value after writing it to see if a newline
has been written.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
2015-05-11 13:59:23 -05:00

58 lines
1.2 KiB
ArmAsm

/*
* arch/arm/include/debug/8250.S
*
* Copyright (C) 1994-2013 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/serial_reg.h>
.macro addruart, rp, rv, tmp
ldr \rp, =CONFIG_DEBUG_UART_PHYS
ldr \rv, =CONFIG_DEBUG_UART_VIRT
.endm
#ifdef CONFIG_DEBUG_UART_8250_WORD
.macro store, rd, rx:vararg
ARM_BE8(rev \rd, \rd)
str \rd, \rx
ARM_BE8(rev \rd, \rd)
.endm
.macro load, rd, rx:vararg
ldr \rd, \rx
ARM_BE8(rev \rd, \rd)
.endm
#else
.macro store, rd, rx:vararg
strb \rd, \rx
.endm
.macro load, rd, rx:vararg
ldrb \rd, \rx
.endm
#endif
#define UART_SHIFT CONFIG_DEBUG_UART_8250_SHIFT
.macro senduart,rd,rx
store \rd, [\rx, #UART_TX << UART_SHIFT]
.endm
.macro busyuart,rd,rx
1002: load \rd, [\rx, #UART_LSR << UART_SHIFT]
and \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
teq \rd, #UART_LSR_TEMT | UART_LSR_THRE
bne 1002b
.endm
.macro waituart,rd,rx
#ifdef CONFIG_DEBUG_UART_8250_FLOW_CONTROL
1001: load \rd, [\rx, #UART_MSR << UART_SHIFT]
tst \rd, #UART_MSR_CTS
beq 1001b
#endif
.endm