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Diffstat (limited to 'gcell/src/ibm/sync/spu_source/cond_init.h')
| -rw-r--r-- | gcell/src/ibm/sync/spu_source/cond_init.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/gcell/src/ibm/sync/spu_source/cond_init.h b/gcell/src/ibm/sync/spu_source/cond_init.h new file mode 100644 index 0000000000..7202e53527 --- /dev/null +++ b/gcell/src/ibm/sync/spu_source/cond_init.h @@ -0,0 +1,127 @@ +/* -------------------------------------------------------------- */ +/* (C)Copyright 2001,2007, */ +/* International Business Machines Corporation, */ +/* Sony Computer Entertainment, Incorporated, */ +/* Toshiba Corporation, */ +/* */ +/* All Rights Reserved. */ +/* */ +/* Redistribution and use in source and binary forms, with or */ +/* without modification, are permitted provided that the */ +/* following conditions are met: */ +/* */ +/* - Redistributions of source code must retain the above copyright*/ +/* notice, this list of conditions and the following disclaimer. */ +/* */ +/* - 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. */ +/* */ +/* - Neither the name of IBM Corporation nor the names of its */ +/* contributors may be used to endorse or promote products */ +/* derived from this software without specific prior written */ +/* permission. */ +/* */ +/* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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. */ +/* -------------------------------------------------------------- */ +/* PROLOG END TAG zYx */ +#ifndef _SPU_COND_INIT_H_ +#define _SPU_COND_INIT_H_ + +#include "sync_utils.h" +#include "cond.h" +#include <spu_mfcio.h> + + +/** + * cond_init - initialize condition variable. + * @cond: handle to effective address of condition variable. + * + * + * Conditional Variable - is a synchronization device that allows + * SPE and PPE threads to suspend execution and relinquish the + * processors until some predicate on shared data is satisfied. + * The basic operations on conditions are: signal the condition + * (when the predicate becomes true), and wait for the condition, + * suspending the thread execution until anoter thread signals the + * condition + * + * A condition variable must always be associated with a mutex, to + * avoid the race condition where a thread prepares to wait on a + * condition variable and another thread signals the condition just + * before the first thread actually waits on it. + * + * cond_init initializes the condition variable cond. + * + * cond_signal restarts one of the threads that are waiting on the + * condition variable cond. If no threads are waiting on cond, nothing + * happens. If several threads are waiting on cond, exactly one + * is restarted, but it is not specified which + * + * cond_broadcast restarts all the threads that are waiting on the + * condition variable cond. Nothing happens if no threads are waiting + * on cond + * + * cond_wait atomically unlocks the mutex and waits for the condition + * variable cond to be signaled. The mutex must be lock locked by + * the calling thread on the entrance to cond_wait. Before returning + * to the calling thread, cond_wait re-acquires mutex. + * + * Only one thread initializes a condition variable. Usually, the + * PPE thread initializes a condidtion variable, however, a cond_init + * function is provided here for completeness + * + * Description: Initialize a cond variable to false. + */ +static __inline void _cond_init(cond_ea_t cond ) +{ + char _tmp[256]; + char *tmp = (char *) ALIGN(_tmp, 128); + volatile unsigned short *buf = (volatile unsigned short *) &tmp[0]; + unsigned int size = 128, tagid; + unsigned int offset; + addr64 ea64; + unsigned int oldtmask; + unsigned int tagmask; + + tagid = mfc_tag_reserve(); + + tagmask = 1 << (tagid & 31); + + ea64.ull = ALIGN128_EA(cond); + offset = OFFSET128_EA_U16(cond); + + MFC_DMA(buf, ea64, size, tagid & 31, MFC_GET_CMD); + oldtmask = spu_readch(MFC_RdTagMask); + spu_writech(MFC_WrTagMask, tagmask); + spu_writech(MFC_WrTagUpdate, MFC_TAG_UPDATE_ANY); + spu_readch(MFC_RdTagStat); + + /* this is still just one word. since buf is of type + * short, we fit both counts into one word. */ + buf[offset] = 0; + buf[offset+1] = 0; + MFC_DMA(buf, ea64, size, (tagid & 31), MFC_PUT_CMD); + spu_writech(MFC_WrTagMask, tagmask); + spu_writech(MFC_WrTagUpdate, MFC_TAG_UPDATE_ANY); + spu_readch(MFC_RdTagStat); + spu_writech(MFC_WrTagMask, oldtmask); + mfc_tag_release (tagid); +} + + + +#endif /* _SPU_COND_INIT_H_ */ |