linux/arch/parisc/include/asm/system.h

166 lines
4.7 KiB
C

#ifndef __PARISC_SYSTEM_H
#define __PARISC_SYSTEM_H
#include <linux/irqflags.h>
/* The program status word as bitfields. */
struct pa_psw {
unsigned int y:1;
unsigned int z:1;
unsigned int rv:2;
unsigned int w:1;
unsigned int e:1;
unsigned int s:1;
unsigned int t:1;
unsigned int h:1;
unsigned int l:1;
unsigned int n:1;
unsigned int x:1;
unsigned int b:1;
unsigned int c:1;
unsigned int v:1;
unsigned int m:1;
unsigned int cb:8;
unsigned int o:1;
unsigned int g:1;
unsigned int f:1;
unsigned int r:1;
unsigned int q:1;
unsigned int p:1;
unsigned int d:1;
unsigned int i:1;
};
#ifdef CONFIG_64BIT
#define pa_psw(task) ((struct pa_psw *) ((char *) (task) + TASK_PT_PSW + 4))
#else
#define pa_psw(task) ((struct pa_psw *) ((char *) (task) + TASK_PT_PSW))
#endif
struct task_struct;
extern struct task_struct *_switch_to(struct task_struct *, struct task_struct *);
#define switch_to(prev, next, last) do { \
(last) = _switch_to(prev, next); \
} while(0)
#define mfctl(reg) ({ \
unsigned long cr; \
__asm__ __volatile__( \
"mfctl " #reg ",%0" : \
"=r" (cr) \
); \
cr; \
})
#define mtctl(gr, cr) \
__asm__ __volatile__("mtctl %0,%1" \
: /* no outputs */ \
: "r" (gr), "i" (cr) : "memory")
/* these are here to de-mystefy the calling code, and to provide hooks */
/* which I needed for debugging EIEM problems -PB */
#define get_eiem() mfctl(15)
static inline void set_eiem(unsigned long val)
{
mtctl(val, 15);
}
#define mfsp(reg) ({ \
unsigned long cr; \
__asm__ __volatile__( \
"mfsp " #reg ",%0" : \
"=r" (cr) \
); \
cr; \
})
#define mtsp(gr, cr) \
__asm__ __volatile__("mtsp %0,%1" \
: /* no outputs */ \
: "r" (gr), "i" (cr) : "memory")
/*
** This is simply the barrier() macro from linux/kernel.h but when serial.c
** uses tqueue.h uses smp_mb() defined using barrier(), linux/kernel.h
** hasn't yet been included yet so it fails, thus repeating the macro here.
**
** PA-RISC architecture allows for weakly ordered memory accesses although
** none of the processors use it. There is a strong ordered bit that is
** set in the O-bit of the page directory entry. Operating systems that
** can not tolerate out of order accesses should set this bit when mapping
** pages. The O-bit of the PSW should also be set to 1 (I don't believe any
** of the processor implemented the PSW O-bit). The PCX-W ERS states that
** the TLB O-bit is not implemented so the page directory does not need to
** have the O-bit set when mapping pages (section 3.1). This section also
** states that the PSW Y, Z, G, and O bits are not implemented.
** So it looks like nothing needs to be done for parisc-linux (yet).
** (thanks to chada for the above comment -ggg)
**
** The __asm__ op below simple prevents gcc/ld from reordering
** instructions across the mb() "call".
*/
#define mb() __asm__ __volatile__("":::"memory") /* barrier() */
#define rmb() mb()
#define wmb() mb()
#define smp_mb() mb()
#define smp_rmb() mb()
#define smp_wmb() mb()
#define smp_read_barrier_depends() do { } while(0)
#define read_barrier_depends() do { } while(0)
#define set_mb(var, value) do { var = value; mb(); } while (0)
#ifndef CONFIG_PA20
/* Because kmalloc only guarantees 8-byte alignment for kmalloc'd data,
and GCC only guarantees 8-byte alignment for stack locals, we can't
be assured of 16-byte alignment for atomic lock data even if we
specify "__attribute ((aligned(16)))" in the type declaration. So,
we use a struct containing an array of four ints for the atomic lock
type and dynamically select the 16-byte aligned int from the array
for the semaphore. */
#define __PA_LDCW_ALIGNMENT 16
#define __ldcw_align(a) ({ \
unsigned long __ret = (unsigned long) &(a)->lock[0]; \
__ret = (__ret + __PA_LDCW_ALIGNMENT - 1) \
& ~(__PA_LDCW_ALIGNMENT - 1); \
(volatile unsigned int *) __ret; \
})
#define __LDCW "ldcw"
#else /*CONFIG_PA20*/
/* From: "Jim Hull" <jim.hull of hp.com>
I've attached a summary of the change, but basically, for PA 2.0, as
long as the ",CO" (coherent operation) completer is specified, then the
16-byte alignment requirement for ldcw and ldcd is relaxed, and instead
they only require "natural" alignment (4-byte for ldcw, 8-byte for
ldcd). */
#define __PA_LDCW_ALIGNMENT 4
#define __ldcw_align(a) (&(a)->slock)
#define __LDCW "ldcw,co"
#endif /*!CONFIG_PA20*/
/* LDCW, the only atomic read-write operation PA-RISC has. *sigh*. */
#define __ldcw(a) ({ \
unsigned __ret; \
__asm__ __volatile__(__LDCW " 0(%2),%0" \
: "=r" (__ret), "+m" (*(a)) : "r" (a)); \
__ret; \
})
#ifdef CONFIG_SMP
# define __lock_aligned __attribute__((__section__(".data..lock_aligned")))
#endif
#define arch_align_stack(x) (x)
#endif