linux/arch/arm/include/asm/dcc.h
Christopher Covington 4061f4987b ARM: tty: Move HVC DCC assembly to arch/arm
Put architecture-specific assembly code where it belongs,
allowing for support of additional architectures such as arm64 in
the future.

Signed-off-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 13:33:18 -07:00

42 lines
1.0 KiB
C

/* Copyright (c) 2010, 2014 The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* 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 <asm/barrier.h>
static inline u32 __dcc_getstatus(void)
{
u32 __ret;
asm volatile("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg"
: "=r" (__ret) : : "cc");
return __ret;
}
static inline char __dcc_getchar(void)
{
char __c;
asm volatile("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
: "=r" (__c));
isb();
return __c;
}
static inline void __dcc_putchar(char c)
{
asm volatile("mcr p14, 0, %0, c0, c5, 0 @ write a char"
: /* no output register */
: "r" (c));
isb();
}