linux_dsm_epyc7002/arch/sparc/include/asm/system_64.h
Mikulas Patocka 019408f9b8 sparc64: Fill a missing delay slot.
If the code were already aligned to 64 bytes, wr instruction would be executed
twice --- once in delay slot and once in the jump target.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-19 14:15:32 -07:00

336 lines
9.5 KiB
C

#ifndef __SPARC64_SYSTEM_H
#define __SPARC64_SYSTEM_H
#include <asm/ptrace.h>
#include <asm/processor.h>
#include <asm/visasm.h>
#ifndef __ASSEMBLY__
#include <linux/irqflags.h>
#include <asm-generic/cmpxchg-local.h>
/*
* Sparc (general) CPU types
*/
enum sparc_cpu {
sun4 = 0x00,
sun4c = 0x01,
sun4m = 0x02,
sun4d = 0x03,
sun4e = 0x04,
sun4u = 0x05, /* V8 ploos ploos */
sun_unknown = 0x06,
ap1000 = 0x07, /* almost a sun4m */
};
#define sparc_cpu_model sun4u
/* This cannot ever be a sun4c :) That's just history. */
#define ARCH_SUN4C 0
extern const char *sparc_cpu_type;
extern const char *sparc_fpu_type;
extern const char *sparc_pmu_type;
extern char reboot_command[];
/* These are here in an effort to more fully work around Spitfire Errata
* #51. Essentially, if a memory barrier occurs soon after a mispredicted
* branch, the chip can stop executing instructions until a trap occurs.
* Therefore, if interrupts are disabled, the chip can hang forever.
*
* It used to be believed that the memory barrier had to be right in the
* delay slot, but a case has been traced recently wherein the memory barrier
* was one instruction after the branch delay slot and the chip still hung.
* The offending sequence was the following in sym_wakeup_done() of the
* sym53c8xx_2 driver:
*
* call sym_ccb_from_dsa, 0
* movge %icc, 0, %l0
* brz,pn %o0, .LL1303
* mov %o0, %l2
* membar #LoadLoad
*
* The branch has to be mispredicted for the bug to occur. Therefore, we put
* the memory barrier explicitly into a "branch always, predicted taken"
* delay slot to avoid the problem case.
*/
#define membar_safe(type) \
do { __asm__ __volatile__("ba,pt %%xcc, 1f\n\t" \
" membar " type "\n" \
"1:\n" \
: : : "memory"); \
} while (0)
/* The kernel always executes in TSO memory model these days,
* and furthermore most sparc64 chips implement more stringent
* memory ordering than required by the specifications.
*/
#define mb() membar_safe("#StoreLoad")
#define rmb() __asm__ __volatile__("":::"memory")
#define wmb() __asm__ __volatile__("":::"memory")
#endif
#define nop() __asm__ __volatile__ ("nop")
#define read_barrier_depends() do { } while(0)
#define set_mb(__var, __value) \
do { __var = __value; membar_safe("#StoreLoad"); } while(0)
#ifdef CONFIG_SMP
#define smp_mb() mb()
#define smp_rmb() rmb()
#define smp_wmb() wmb()
#else
#define smp_mb() __asm__ __volatile__("":::"memory")
#define smp_rmb() __asm__ __volatile__("":::"memory")
#define smp_wmb() __asm__ __volatile__("":::"memory")
#endif
#define smp_read_barrier_depends() do { } while(0)
#define flushi(addr) __asm__ __volatile__ ("flush %0" : : "r" (addr) : "memory")
#define flushw_all() __asm__ __volatile__("flushw")
/* Performance counter register access. */
#define read_pcr(__p) __asm__ __volatile__("rd %%pcr, %0" : "=r" (__p))
#define write_pcr(__p) __asm__ __volatile__("wr %0, 0x0, %%pcr" : : "r" (__p))
#define read_pic(__p) __asm__ __volatile__("rd %%pic, %0" : "=r" (__p))
/* Blackbird errata workaround. See commentary in
* arch/sparc64/kernel/smp.c:smp_percpu_timer_interrupt()
* for more information.
*/
#define write_pic(__p) \
__asm__ __volatile__("ba,pt %%xcc, 99f\n\t" \
" nop\n\t" \
".align 64\n" \
"99:wr %0, 0x0, %%pic\n\t" \
"rd %%pic, %%g0" : : "r" (__p))
#define reset_pic() write_pic(0)
#ifndef __ASSEMBLY__
extern void sun_do_break(void);
extern int stop_a_enabled;
extern int scons_pwroff;
extern void fault_in_user_windows(void);
extern void synchronize_user_stack(void);
extern void __flushw_user(void);
#define flushw_user() __flushw_user()
#define flush_user_windows flushw_user
#define flush_register_windows flushw_all
/* Don't hold the runqueue lock over context switch */
#define __ARCH_WANT_UNLOCKED_CTXSW
#define prepare_arch_switch(next) \
do { \
flushw_all(); \
} while (0)
/* See what happens when you design the chip correctly?
*
* We tell gcc we clobber all non-fixed-usage registers except
* for l0/l1. It will use one for 'next' and the other to hold
* the output value of 'last'. 'next' is not referenced again
* past the invocation of switch_to in the scheduler, so we need
* not preserve it's value. Hairy, but it lets us remove 2 loads
* and 2 stores in this critical code path. -DaveM
*/
#define switch_to(prev, next, last) \
do { flush_tlb_pending(); \
save_and_clear_fpu(); \
/* If you are tempted to conditionalize the following */ \
/* so that ASI is only written if it changes, think again. */ \
__asm__ __volatile__("wr %%g0, %0, %%asi" \
: : "r" (__thread_flag_byte_ptr(task_thread_info(next))[TI_FLAG_BYTE_CURRENT_DS]));\
trap_block[current_thread_info()->cpu].thread = \
task_thread_info(next); \
__asm__ __volatile__( \
"mov %%g4, %%g7\n\t" \
"stx %%i6, [%%sp + 2047 + 0x70]\n\t" \
"stx %%i7, [%%sp + 2047 + 0x78]\n\t" \
"rdpr %%wstate, %%o5\n\t" \
"stx %%o6, [%%g6 + %6]\n\t" \
"stb %%o5, [%%g6 + %5]\n\t" \
"rdpr %%cwp, %%o5\n\t" \
"stb %%o5, [%%g6 + %8]\n\t" \
"wrpr %%g0, 15, %%pil\n\t" \
"mov %4, %%g6\n\t" \
"ldub [%4 + %8], %%g1\n\t" \
"wrpr %%g1, %%cwp\n\t" \
"ldx [%%g6 + %6], %%o6\n\t" \
"ldub [%%g6 + %5], %%o5\n\t" \
"ldub [%%g6 + %7], %%o7\n\t" \
"wrpr %%o5, 0x0, %%wstate\n\t" \
"ldx [%%sp + 2047 + 0x70], %%i6\n\t" \
"ldx [%%sp + 2047 + 0x78], %%i7\n\t" \
"ldx [%%g6 + %9], %%g4\n\t" \
"wrpr %%g0, 14, %%pil\n\t" \
"brz,pt %%o7, switch_to_pc\n\t" \
" mov %%g7, %0\n\t" \
"sethi %%hi(ret_from_syscall), %%g1\n\t" \
"jmpl %%g1 + %%lo(ret_from_syscall), %%g0\n\t" \
" nop\n\t" \
".globl switch_to_pc\n\t" \
"switch_to_pc:\n\t" \
: "=&r" (last), "=r" (current), "=r" (current_thread_info_reg), \
"=r" (__local_per_cpu_offset) \
: "0" (task_thread_info(next)), \
"i" (TI_WSTATE), "i" (TI_KSP), "i" (TI_NEW_CHILD), \
"i" (TI_CWP), "i" (TI_TASK) \
: "cc", \
"g1", "g2", "g3", "g7", \
"l1", "l2", "l3", "l4", "l5", "l6", "l7", \
"i0", "i1", "i2", "i3", "i4", "i5", \
"o0", "o1", "o2", "o3", "o4", "o5", "o7"); \
} while(0)
static inline unsigned long xchg32(__volatile__ unsigned int *m, unsigned int val)
{
unsigned long tmp1, tmp2;
__asm__ __volatile__(
" mov %0, %1\n"
"1: lduw [%4], %2\n"
" cas [%4], %2, %0\n"
" cmp %2, %0\n"
" bne,a,pn %%icc, 1b\n"
" mov %1, %0\n"
: "=&r" (val), "=&r" (tmp1), "=&r" (tmp2)
: "0" (val), "r" (m)
: "cc", "memory");
return val;
}
static inline unsigned long xchg64(__volatile__ unsigned long *m, unsigned long val)
{
unsigned long tmp1, tmp2;
__asm__ __volatile__(
" mov %0, %1\n"
"1: ldx [%4], %2\n"
" casx [%4], %2, %0\n"
" cmp %2, %0\n"
" bne,a,pn %%xcc, 1b\n"
" mov %1, %0\n"
: "=&r" (val), "=&r" (tmp1), "=&r" (tmp2)
: "0" (val), "r" (m)
: "cc", "memory");
return val;
}
#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
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 xchg32(ptr, x);
case 8:
return xchg64(ptr, x);
};
__xchg_called_with_bad_pointer();
return x;
}
extern void die_if_kernel(char *str, struct pt_regs *regs) __attribute__ ((noreturn));
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
#define __HAVE_ARCH_CMPXCHG 1
static inline unsigned long
__cmpxchg_u32(volatile int *m, int old, int new)
{
__asm__ __volatile__("cas [%2], %3, %0"
: "=&r" (new)
: "0" (new), "r" (m), "r" (old)
: "memory");
return new;
}
static inline unsigned long
__cmpxchg_u64(volatile long *m, unsigned long old, unsigned long new)
{
__asm__ __volatile__("casx [%2], %3, %0"
: "=&r" (new)
: "0" (new), "r" (m), "r" (old)
: "memory");
return new;
}
/* This function doesn't exist, so you'll get a linker error
if something tries to do an invalid cmpxchg(). */
extern void __cmpxchg_called_with_bad_pointer(void);
static inline unsigned long
__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
{
switch (size) {
case 4:
return __cmpxchg_u32(ptr, old, new);
case 8:
return __cmpxchg_u64(ptr, old, new);
}
__cmpxchg_called_with_bad_pointer();
return old;
}
#define cmpxchg(ptr,o,n) \
({ \
__typeof__(*(ptr)) _o_ = (o); \
__typeof__(*(ptr)) _n_ = (n); \
(__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
(unsigned long)_n_, sizeof(*(ptr))); \
})
/*
* cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
* them available.
*/
static inline unsigned long __cmpxchg_local(volatile void *ptr,
unsigned long old,
unsigned long new, int size)
{
switch (size) {
case 4:
case 8: return __cmpxchg(ptr, old, new, size);
default:
return __cmpxchg_local_generic(ptr, old, new, size);
}
return old;
}
#define cmpxchg_local(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg64_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg_local((ptr), (o), (n)); \
})
#endif /* !(__ASSEMBLY__) */
#define arch_align_stack(x) (x)
#endif /* !(__SPARC64_SYSTEM_H) */