kernel-ark/include/asm-mips/system.h
Thomas Bogendoerfer 68576cf122 IP22ZILOG: fix lockup and sysrq
- fix lockup when switching from early console to real console
 - make sysrq reliable
 - fix panic, if sysrq is issued before console is opened

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:53 -08:00

221 lines
5.6 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994, 95, 96, 97, 98, 99, 2003, 06 by Ralf Baechle
* Copyright (C) 1996 by Paul M. Antoine
* Copyright (C) 1999 Silicon Graphics
* Kevin D. Kissell, kevink@mips.org and Carsten Langgaard, carstenl@mips.com
* Copyright (C) 2000 MIPS Technologies, Inc.
*/
#ifndef _ASM_SYSTEM_H
#define _ASM_SYSTEM_H
#include <linux/types.h>
#include <linux/irqflags.h>
#include <asm/addrspace.h>
#include <asm/barrier.h>
#include <asm/cmpxchg.h>
#include <asm/cpu-features.h>
#include <asm/dsp.h>
#include <asm/war.h>
/*
* switch_to(n) should switch tasks to task nr n, first
* checking that n isn't the current task, in which case it does nothing.
*/
extern asmlinkage void *resume(void *last, void *next, void *next_ti);
struct task_struct;
#ifdef CONFIG_MIPS_MT_FPAFF
/*
* Handle the scheduler resume end of FPU affinity management. We do this
* inline to try to keep the overhead down. If we have been forced to run on
* a "CPU" with an FPU because of a previous high level of FP computation,
* but did not actually use the FPU during the most recent time-slice (CU1
* isn't set), we undo the restriction on cpus_allowed.
*
* We're not calling set_cpus_allowed() here, because we have no need to
* force prompt migration - we're already switching the current CPU to a
* different thread.
*/
#define __mips_mt_fpaff_switch_to(prev) \
do { \
struct thread_info *__prev_ti = task_thread_info(prev); \
\
if (cpu_has_fpu && \
test_ti_thread_flag(__prev_ti, TIF_FPUBOUND) && \
(!(KSTK_STATUS(prev) & ST0_CU1))) { \
clear_ti_thread_flag(__prev_ti, TIF_FPUBOUND); \
prev->cpus_allowed = prev->thread.user_cpus_allowed; \
} \
next->thread.emulated_fp = 0; \
} while(0)
#else
#define __mips_mt_fpaff_switch_to(prev) do { (void) (prev); } while (0)
#endif
#define switch_to(prev, next, last) \
do { \
__mips_mt_fpaff_switch_to(prev); \
if (cpu_has_dsp) \
__save_dsp(prev); \
(last) = resume(prev, next, task_thread_info(next)); \
} while (0)
#define finish_arch_switch(prev) \
do { \
if (cpu_has_dsp) \
__restore_dsp(current); \
if (cpu_has_userlocal) \
write_c0_userlocal(current_thread_info()->tp_value); \
} while (0)
static inline unsigned long __xchg_u32(volatile int * m, unsigned int val)
{
__u32 retval;
if (cpu_has_llsc && R10000_LLSC_WAR) {
unsigned long dummy;
__asm__ __volatile__(
" .set mips3 \n"
"1: ll %0, %3 # xchg_u32 \n"
" .set mips0 \n"
" move %2, %z4 \n"
" .set mips3 \n"
" sc %2, %1 \n"
" beqzl %2, 1b \n"
" .set mips0 \n"
: "=&r" (retval), "=m" (*m), "=&r" (dummy)
: "R" (*m), "Jr" (val)
: "memory");
} else if (cpu_has_llsc) {
unsigned long dummy;
__asm__ __volatile__(
" .set mips3 \n"
"1: ll %0, %3 # xchg_u32 \n"
" .set mips0 \n"
" move %2, %z4 \n"
" .set mips3 \n"
" sc %2, %1 \n"
" beqz %2, 2f \n"
" .subsection 2 \n"
"2: b 1b \n"
" .previous \n"
" .set mips0 \n"
: "=&r" (retval), "=m" (*m), "=&r" (dummy)
: "R" (*m), "Jr" (val)
: "memory");
} else {
unsigned long flags;
raw_local_irq_save(flags);
retval = *m;
*m = val;
raw_local_irq_restore(flags); /* implies memory barrier */
}
smp_llsc_mb();
return retval;
}
#ifdef CONFIG_64BIT
static inline __u64 __xchg_u64(volatile __u64 * m, __u64 val)
{
__u64 retval;
if (cpu_has_llsc && R10000_LLSC_WAR) {
unsigned long dummy;
__asm__ __volatile__(
" .set mips3 \n"
"1: lld %0, %3 # xchg_u64 \n"
" move %2, %z4 \n"
" scd %2, %1 \n"
" beqzl %2, 1b \n"
" .set mips0 \n"
: "=&r" (retval), "=m" (*m), "=&r" (dummy)
: "R" (*m), "Jr" (val)
: "memory");
} else if (cpu_has_llsc) {
unsigned long dummy;
__asm__ __volatile__(
" .set mips3 \n"
"1: lld %0, %3 # xchg_u64 \n"
" move %2, %z4 \n"
" scd %2, %1 \n"
" beqz %2, 2f \n"
" .subsection 2 \n"
"2: b 1b \n"
" .previous \n"
" .set mips0 \n"
: "=&r" (retval), "=m" (*m), "=&r" (dummy)
: "R" (*m), "Jr" (val)
: "memory");
} else {
unsigned long flags;
raw_local_irq_save(flags);
retval = *m;
*m = val;
raw_local_irq_restore(flags); /* implies memory barrier */
}
smp_llsc_mb();
return retval;
}
#else
extern __u64 __xchg_u64_unsupported_on_32bit_kernels(volatile __u64 * m, __u64 val);
#define __xchg_u64 __xchg_u64_unsupported_on_32bit_kernels
#endif
/* This function doesn't exist, so you'll get a linker error
if something tries to do an invalid xchg(). */
extern void __xchg_called_with_bad_pointer(void);
static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
{
switch (size) {
case 4:
return __xchg_u32(ptr, x);
case 8:
return __xchg_u64(ptr, x);
}
__xchg_called_with_bad_pointer();
return x;
}
#define xchg(ptr, x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
extern void set_handler(unsigned long offset, void *addr, unsigned long len);
extern void set_uncached_handler(unsigned long offset, void *addr, unsigned long len);
typedef void (*vi_handler_t)(void);
extern void *set_vi_handler(int n, vi_handler_t addr);
extern void *set_except_vector(int n, void *addr);
extern unsigned long ebase;
extern void per_cpu_trap_init(void);
/*
* See include/asm-ia64/system.h; prevents deadlock on SMP
* systems.
*/
#define __ARCH_WANT_UNLOCKED_CTXSW
extern unsigned long arch_align_stack(unsigned long sp);
#endif /* _ASM_SYSTEM_H */