/*      $NetBSD: syncicache.c,v 1.14 2008/03/18 20:11:43 he Exp $       */

/*
* Copyright (C) 1995-1997, 1999 Wolfgang Solfrank.
* Copyright (C) 1995-1997, 1999 TooLs GmbH.
* 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 TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
*    derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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.
*/
#include <sys/param.h>
#if     defined(_KERNEL)
#include <sys/time.h>
#include <sys/proc.h>
#include <uvm/uvm_extern.h>
#endif
#if     !defined(_STANDALONE)
#include <sys/sysctl.h>
#endif

#include <machine/cpu.h>


#if defined(_STANDALONE)
#ifndef CACHELINESIZE
#error "Must know the size of a cache line"
#endif
static struct cache_info _cache_info = {
       CACHELINESIZE,
       CACHELINESIZE,
       CACHELINESIZE,
       CACHELINESIZE
};
#define CACHEINFO       _cache_info
#elif defined(_KERNEL)
#define CACHEINFO       (curcpu()->ci_ci)
#else
static void getcachelinesize (void);

static int _cachelinesize = 0;

static struct cache_info _cache_info;
#define CACHEINFO       _cache_info

static void
getcachelinesize(void)
{
       static int cachemib[] = { CTL_MACHDEP, CPU_CACHELINE };
       static int cacheinfomib[] = { CTL_MACHDEP, CPU_CACHEINFO };
       size_t clen = sizeof(_cache_info);

       if (sysctl(cacheinfomib, sizeof(cacheinfomib) / sizeof(cacheinfomib[0]),
               &_cache_info, &clen, NULL, 0) == 0) {
               _cachelinesize = _cache_info.dcache_line_size;
               return;
       }

       /* Try older deprecated sysctl */
       clen = sizeof(_cachelinesize);
       if (sysctl(cachemib, sizeof(cachemib) / sizeof(cachemib[0]),
                  &_cachelinesize, &clen, NULL, 0) < 0
           || !_cachelinesize)
               abort();

       _cache_info.dcache_size = _cachelinesize;
       _cache_info.dcache_line_size = _cachelinesize;
       _cache_info.icache_size = _cachelinesize;
       _cache_info.icache_line_size = _cachelinesize;
       /* If there is no cache, indicate we have issued the sysctl. */
       if (!_cachelinesize)
               _cachelinesize = 1;
}
#endif

void
__syncicache(void *from, size_t len)
{
       size_t l, off;
       size_t linesz;
       char *p;

#if     !defined(_KERNEL) && !defined(_STANDALONE)
       if (!_cachelinesize)
               getcachelinesize();
#endif

       if (CACHEINFO.dcache_size > 0) {
               linesz = CACHEINFO.dcache_line_size;
               off = (uintptr_t)from & (linesz - 1);
               l = (len + off + linesz - 1) & ~(linesz - 1);
               p = (char *)from - off;
               do {
                       __asm volatile ("dcbst 0,%0" :: "r"(p));
                       p += linesz;
               } while ((l -= linesz) != 0);
       }
       __asm volatile ("sync");

       if (CACHEINFO.icache_size > 0 ) {
               linesz = CACHEINFO.icache_line_size;
               off = (uintptr_t)from & (linesz - 1);
               l = (len + off + linesz - 1) & ~(linesz - 1);
               p = (char *)from - off;
               do {
                       __asm volatile ("icbi 0,%0" :: "r"(p));
                       p += linesz;
               } while ((l -= linesz) != 0);
       }
       __asm volatile ("sync; isync");
}