freebsd-nq/sys/arm/arm/cpufunc_asm.S
Olivier Houchard f4c01f1508 Instead of using sysarch() to store-retrieve the tp, add a magic address,
ARM_TP_ADDRESS, where the tp will be stored. On CPUs that support it, a cache
line will be allocated and locked for this address, so that it will never go
to RAM. On CPUs that does not, a page is allocated for it (it will be a bit
slower, and is wrong for SMP, but should be fine for UP).
The tp is still stored in the mdthread struct, and at each context switch,
ARM_TP_ADDRESS gets updated.

Suggested by:   davidxu
2005-02-26 18:59:01 +00:00

179 lines
4.7 KiB
ArmAsm

/* $NetBSD: cpufunc_asm.S,v 1.12 2003/09/06 09:14:52 rearnsha 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 <machine/asm.h>
__FBSDID("$FreeBSD$");
.text
.align 0
ENTRY(cpufunc_nullop)
RET
/*
* 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
ENTRY(cpu_get_control)
mrc p15, 0, r0, c1, c0, 0
RET
ENTRY(cpu_read_cache_config)
mrc p15, 0, r0, c0, c0, 1
RET
ENTRY(cpufunc_faultstatus)
mrc p15, 0, r0, c5, c0, 0
RET
ENTRY(cpufunc_faultaddress)
mrc p15, 0, r0, c6, c0, 0
RET
/*
* 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
/*
* 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 */
bic r2, r3, r0 /* Clear bits */
eor r2, r2, r1 /* XOR bits */
teq r2, r3 /* Only write if there is a change */
mcrne p15, 0, r2, c1, c0, 0 /* Write new control register */
mov r0, r3 /* Return old value */
RET
.Lglou:
.asciz "plop %p\n"
.align 0
/*
* 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.
*/
ENTRY(get_pc_str_offset)
mov ip, sp
stmfd sp!, {fp, ip, lr, pc}
sub fp, ip, #4
sub sp, sp, #4
mov r1, pc /* R1 = addr of following STR */
mov r0, r0
str pc, [sp] /* [SP] = . + offset */
ldr r0, [sp]
sub r0, r0, r1
ldmdb fp, {fp, sp, pc}
/* Allocate and lock a cacheline for the specified address. */
#define CPWAIT_BRANCH \
sub pc, pc, #4
#define CPWAIT() \
mrc p15, 0, r2, c2, c0, 0; \
mov r2, r2; \
CPWAIT_BRANCH
ENTRY(arm_lock_cache_line)
mcr p15, 0, r0, c7, c10, 4 /* Drain write buffer */
mov r1, #1
mcr p15, 0, r1, c9, c2, 0 /* Enable data cache lock mode */
CPWAIT()
mcr p15, 0, r0, c7, c2, 5 /* Allocate the cache line */
mcr p15, 0, r0, c7, c10, 4 /* Drain write buffer */
mov r1, #0
str r1, [r0]
mcr p15, 0, r0, c7, c10, 4 /* Drain write buffer */
mcr p15, 0, r1, c9, c2, 0 /* Disable data cache lock mode */
CPWAIT()
RET