freebsd-dev/sys/sparc64/include/cpufunc.h
Marius Strobl 7bed9b320b - Add a workaround for a bug in BlackBird CPUs (said to be part of the
SpitFire erratum #54) which can cause writes to the TICK_CMPR register
  to fail. This seems to fix the dying clocks problem reported by jhb@
  and kris@. [1]
- In tick_start() don't reset the tick counter of the boot processor to
  zero. It's initially reset in _start() and afterwards but _before_
  tick_start() is called on the BSP the APs synchronise with the tick
  counter of the BSP in mp_startup(). Resetting the tick counter of the
  BSP in tick_start() probably also was the cause of problems seen when
  using the CPU tick counter as timecounter on SMP machines.
  Not resetting the tick counter of the BSP in mp_startup() makes the
  tick counters and tick interrupts between the BSP and APs be pretty
  much in sync as it's supposed to be. This also means there's no longer
  a real reason to have separate tick_start() and tick_start_ap() so
  merge them and zap tick_start_ap(). This is also a first step in
  simplifying the interface to the tick counters in preparation to use
  alternate clock hardware where available.
- Switch to the algorithm used on FreeBSD/ia64 for updating the tick
  interrupt register and which compensates the clock drift caused by
  varying delays between when the tick interrupts actually trigger and
  when they are serviced. Not compensating the clock drift mainly hurts
  interactive performance especially when using WITNESS. [2]
  For further information about the algorithm also see the commit log
  of sys/ia64/ia64/interrupt.c rev. 1.38.
  On sparc64 the sysctls for monitoring the behaviour of the tick
  interrupts are machdep.tick.adjust_edges, machdep.tick.adjust_excess,
  machdep.tick.adjust_missed and machdep.tick.adjust_ticks.
- In tick_init() just use tick_stop() for stopping the tick interrupts
  until a proper handler is set up later. This also stops the system
  tick interrupt on USIII systems earlier.
- In tick_start() check for a rough upper limit of HZ.
- Some minor changes, e.g. use FBSDID, remove unused headers, etc.

Info obtained from:	Linux [1]
Ok'ed by:		marcel [2]
Additional testing by:	kris (earlier version of the workaround), jhb
X-MFC after:		3 days [1]
2005-04-16 14:57:38 +00:00

255 lines
7.3 KiB
C

/*-
* Copyright (c) 2001 Jake Burkholder.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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.
*
* $FreeBSD$
*/
#ifndef _MACHINE_CPUFUNC_H_
#define _MACHINE_CPUFUNC_H_
#include <machine/asi.h>
#include <machine/pstate.h>
struct thread;
/*
* membar operand macros for use in other macros when # is a special
* character. Keep these in sync with what the hardware expects.
*/
#define C_Lookaside (0)
#define C_MemIssue (1)
#define C_Sync (2)
#define M_LoadLoad (0)
#define M_StoreLoad (1)
#define M_LoadStore (2)
#define M_StoreStore (3)
#define CMASK_SHIFT (4)
#define MMASK_SHIFT (0)
#define CMASK_GEN(bit) ((1 << (bit)) << CMASK_SHIFT)
#define MMASK_GEN(bit) ((1 << (bit)) << MMASK_SHIFT)
#define Lookaside CMASK_GEN(C_Lookaside)
#define MemIssue CMASK_GEN(C_MemIssue)
#define Sync CMASK_GEN(C_Sync)
#define LoadLoad MMASK_GEN(M_LoadLoad)
#define StoreLoad MMASK_GEN(M_StoreLoad)
#define LoadStore MMASK_GEN(M_LoadStore)
#define StoreStore MMASK_GEN(M_StoreStore)
#define casa(rs1, rs2, rd, asi) ({ \
u_int __rd = (uint32_t)(rd); \
__asm __volatile("casa [%1] %2, %3, %0" \
: "+r" (__rd) : "r" (rs1), "n" (asi), "r" (rs2)); \
__rd; \
})
#define casxa(rs1, rs2, rd, asi) ({ \
u_long __rd = (uint64_t)(rd); \
__asm __volatile("casxa [%1] %2, %3, %0" \
: "+r" (__rd) : "r" (rs1), "n" (asi), "r" (rs2)); \
__rd; \
})
#define flush(va) do { \
__asm __volatile("flush %0" : : "r" (va)); \
} while (0)
#define flushw() do { \
__asm __volatile("flushw" : :); \
} while (0)
#define mov(val, reg) do { \
__asm __volatile("mov %0, %" __XSTRING(reg) : : "r" (val)); \
} while (0)
/* Generate ld*a/st*a functions for non-constant ASI's. */
#define LDNC_GEN(tp, o) \
static __inline tp \
o ## _nc(caddr_t va, int asi) \
{ \
tp r; \
__asm __volatile("wr %2, 0, %%asi;" #o " [%1] %%asi, %0"\
: "=r" (r) : "r" (va), "r" (asi)); \
return (r); \
}
LDNC_GEN(u_char, lduba);
LDNC_GEN(u_short, lduha);
LDNC_GEN(u_int, lduwa);
LDNC_GEN(u_long, ldxa);
#define LD_GENERIC(va, asi, op, type) ({ \
type __r; \
__asm __volatile(#op " [%1] %2, %0" \
: "=r" (__r) : "r" (va), "n" (asi)); \
__r; \
})
#define lduba(va, asi) LD_GENERIC(va, asi, lduba, u_char)
#define lduha(va, asi) LD_GENERIC(va, asi, lduha, u_short)
#define lduwa(va, asi) LD_GENERIC(va, asi, lduwa, u_int)
#define ldxa(va, asi) LD_GENERIC(va, asi, ldxa, u_long)
#define STNC_GEN(tp, o) \
static __inline void \
o ## _nc(caddr_t va, int asi, tp val) \
{ \
__asm __volatile("wr %2, 0, %%asi;" #o " %0, [%1] %%asi"\
: : "r" (val), "r" (va), "r" (asi)); \
}
STNC_GEN(u_char, stba);
STNC_GEN(u_short, stha);
STNC_GEN(u_int, stwa);
STNC_GEN(u_long, stxa);
#define ST_GENERIC(va, asi, val, op) \
__asm __volatile(#op " %0, [%1] %2" \
: : "r" (val), "r" (va), "n" (asi)); \
#define stba(va, asi, val) ST_GENERIC(va, asi, val, stba)
#define stha(va, asi, val) ST_GENERIC(va, asi, val, stha)
#define stwa(va, asi, val) ST_GENERIC(va, asi, val, stwa)
#define stxa(va, asi, val) ST_GENERIC(va, asi, val, stxa)
/*
* Attempt to read from addr, val. If a Data Access Error trap happens,
* they return -1 and the contents of val is undefined. A return of 0
* means no trap happened, and the contents of val is valid.
*/
int fasword8(u_long asi, void *addr, uint8_t *val);
int fasword16(u_long asi, void *addr, uint16_t *val);
int fasword32(u_long asi, void *addr, uint32_t *val);
#define membar(mask) do { \
__asm __volatile("membar %0" : : "n" (mask) : "memory"); \
} while (0)
#define rd(name) ({ \
uint64_t __sr; \
__asm __volatile("rd %%" #name ", %0" : "=r" (__sr) :); \
__sr; \
})
#define wr(name, val, xor) do { \
__asm __volatile("wr %0, %1, %%" #name \
: : "r" (val), "rI" (xor)); \
} while (0)
#define rdpr(name) ({ \
uint64_t __pr; \
__asm __volatile("rdpr %%" #name", %0" : "=r" (__pr) :); \
__pr; \
})
#define wrpr(name, val, xor) do { \
__asm __volatile("wrpr %0, %1, %%" #name \
: : "r" (val), "rI" (xor)); \
} while (0)
/*
* Macro intended to be used instead of wr(asr23, val, xor) for writing to
* the TICK_CMPR register in order to avoid a bug in BlackBird CPUs that
* can cause these writes to fail under certain condidtions which in turn
* causes the hardclock to stop. The workaround is to perform the write
* at the beginning of an I-Cache line directly followed by a dummy read.
*/
#define wrtickcmpr(val, xor) ({ \
__asm __volatile( \
" ba,pt %%xcc, 1f ; " \
" nop ; " \
" .align 64 ; " \
"1: wr %0, %1, %%asr23 ; " \
" rd %%asr23, %%g0 ; " \
: : "r" (val), "rI" (xor)); \
})
static __inline void
breakpoint(void)
{
__asm __volatile("ta %%xcc, 1" : :);
}
static __inline register_t
intr_disable(void)
{
u_long s;
s = rdpr(pstate);
wrpr(pstate, s & ~PSTATE_IE, 0);
return (s);
}
#define intr_restore(s) wrpr(pstate, (s), 0)
/*
* In some places, it is required that the store is directly followed by a
* membar #Sync. Don't trust the compiler to not insert instructions in
* between. We also need to disable interrupts completely.
*/
#define stxa_sync(va, asi, val) do { \
u_long s; \
s = intr_disable(); \
__asm __volatile("stxa %0, [%1] %2; membar #Sync" \
: : "r" (val), "r" (va), "n" (asi)); \
intr_restore(s); \
} while (0)
void ascopy(u_long asi, vm_offset_t src, vm_offset_t dst, size_t len);
void ascopyfrom(u_long sasi, vm_offset_t src, caddr_t dst, size_t len);
void ascopyto(caddr_t src, u_long dasi, vm_offset_t dst, size_t len);
void aszero(u_long asi, vm_offset_t dst, size_t len);
/*
* Ultrasparc II doesn't implement popc in hardware. Suck.
*/
#if 0
#define HAVE_INLINE_FFS
/*
* See page 202 of the SPARC v9 Architecture Manual.
*/
static __inline int
ffs(int mask)
{
int result;
int neg;
int tmp;
__asm __volatile(
" neg %3, %1 ; "
" xnor %3, %1, %2 ; "
" popc %2, %0 ; "
" movrz %3, %%g0, %0 ; "
: "=r" (result), "=r" (neg), "=r" (tmp) : "r" (mask));
return (result);
}
#endif
#undef LDNC_GEN
#undef STNC_GEN
#endif /* !_MACHINE_CPUFUNC_H_ */