netbsd/sys/arch/arm/arm/cpufunc_asm.S
2014-01-15 10:53:42 +01:00

165 lines
4.3 KiB
ArmAsm

/* $NetBSD: cpufunc_asm.S,v 1.16 2013/08/18 06:28:18 matt Exp $ */
/*
* Copyright (c) 1997,1998 Mark Brinicombe.
* Copyright (c) 1997 Causality Limited
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Causality Limited.
* 4. The name of Causality Limited may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY CAUSALITY LIMITED ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL CAUSALITY LIMITED BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* RiscBSD kernel project
*
* cpufunc.S
*
* Assembly functions for CPU / MMU / TLB specific operations
*
* Created : 30/01/97
*/
#include <arm/armreg.h>
#include <machine/asm.h>
.text
.align 0
ENTRY(cpufunc_nullop)
RET
END(cpufunc_nullop)
/*
* Generic functions to read the internal coprocessor registers
*
* Currently these registers are :
* c0 - CPU ID
* c5 - Fault status
* c6 - Fault address
*
*/
ENTRY(cpufunc_id)
mrc p15, 0, r0, c0, c0, 0
RET
END(cpufunc_id)
ENTRY(cpu_read_cache_config)
mrc p15, 0, r0, c0, c0, 1
RET
END(cpu_read_cache_config)
ENTRY(cpu_get_control)
mrc p15, 0, r0, c1, c0, 0
RET
END(cpu_get_control)
ENTRY(cpufunc_faultstatus)
mrc p15, 0, r0, c5, c0, 0
RET
END(cpufunc_faultstatus)
ENTRY(cpufunc_faultaddress)
mrc p15, 0, r0, c6, c0, 0
RET
END(cpufunc_faultaddress)
/*
* Generic functions to write the internal coprocessor registers
*
*
* Currently these registers are
* c1 - CPU Control
* c3 - Domain Access Control
*
* All other registers are CPU architecture specific
*/
#if 0 /* See below. */
ENTRY(cpufunc_control)
mcr p15, 0, r0, c1, c0, 0
RET
#endif
ENTRY(cpufunc_domains)
mcr p15, 0, r0, c3, c0, 0
RET
END(cpufunc_domains)
/*
* Generic functions to read/modify/write the internal coprocessor registers
*
*
* Currently these registers are
* c1 - CPU Control
*
* All other registers are CPU architecture specific
*/
ENTRY(cpufunc_control)
mrc p15, 0, r3, c1, c0, 0 /* Read the control register */
bics r2, r3, r0 /* Clear bits */
eors r2, r2, r1 /* XOR bits */
teq r2, r3 /* Only write if there is a change */
#ifdef __thumb__
it ne
#endif
mcrne p15, 0, r2, c1, c0, 0 /* Write new control register */
movs r0, r3 /* Return old value */
RET
END(cpufunc_control)
/*
* other potentially useful software functions are:
* clean D cache entry and flush I cache entry
* for the moment use cache_purgeID_E
*/
/* Random odd functions */
/*
* Function to get the offset of a stored program counter from the
* instruction doing the store. This offset is defined to be the same
* for all STRs and STMs on a given implementation. Code based on
* section 2.4.3 of the ARM ARM (2nd Ed.), with modifications to work
* in 26-bit modes as well. In Thumb mode, the PC can't be directly
* stored.
*/
ENTRY(get_pc_str_offset)
#ifdef __thumb__
mov r0, #4
RET
#else
mov r1, pc /* R1 = addr of following STR */
mov r8, r8
push {pc} /* [SP] = . + offset */
pop {r0}
subs r0, r0, r1
RET
#endif
END(get_pc_str_offset)