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gemini_ipmvar.h revision 1.1.4.2 
      1  1.1.4.2  mjf /*	$NetBSD: gemini_ipmvar.h,v 1.1.4.2 2009/01/17 13:27:52 mjf Exp $	*/
      2  1.1.4.2  mjf 
      3  1.1.4.2  mjf #ifndef _GEMINI_IPMVAR_H_
      4  1.1.4.2  mjf #define _GEMINI_IPMVAR_H_
      5  1.1.4.2  mjf 
      6  1.1.4.2  mjf /*
      7  1.1.4.2  mjf  * message queue
      8  1.1.4.2  mjf  *
      9  1.1.4.2  mjf  * - the queue gets located in memory shared between cores
     10  1.1.4.2  mjf  * - is mapped non-cached so SW coherency is not required.
     11  1.1.4.2  mjf  * - be sure ipm_queue_t starts on 32 bit (min) boundary to align descriptors
     12  1.1.4.2  mjf  * - note that indicies are 8 bit and NIPMDESC < (1<<8)
     13  1.1.4.2  mjf  *   be sure to adjust typedef if size is increased
     14  1.1.4.2  mjf  * - current sizes, typedef, and padding make sizeof(ipm_queue_t) == 4096
     15  1.1.4.2  mjf  */
     16  1.1.4.2  mjf typedef uint32_t ipmqindex_t;
     17  1.1.4.2  mjf #define NIPMDESC	255
     18  1.1.4.2  mjf #define IPMQPADSZ	(4096 - ((sizeof(ipm_desc_t) * NIPMDESC) + (2 * sizeof(ipmqindex_t))))
     19  1.1.4.2  mjf typedef struct ipm_queue {
     20  1.1.4.2  mjf 	ipm_desc_t ipm_desc[NIPMDESC];
     21  1.1.4.2  mjf 	volatile ipmqindex_t ix_write; /* writer increments and inserts here  */
     22  1.1.4.2  mjf 	volatile ipmqindex_t ix_read;  /* reader extracts here and increments */
     23  1.1.4.2  mjf 	uint8_t pad[IPMQPADSZ];
     24  1.1.4.2  mjf } ipm_queue_t;
     25  1.1.4.2  mjf 
     26  1.1.4.2  mjf static inline ipmqindex_t
     27  1.1.4.2  mjf ipmqnext(ipmqindex_t ix)
     28  1.1.4.2  mjf {
     29  1.1.4.2  mjf 	if (++ix >= NIPMDESC)
     30  1.1.4.2  mjf 		ix = 0;
     31  1.1.4.2  mjf 	return ix;
     32  1.1.4.2  mjf }
     33  1.1.4.2  mjf 
     34  1.1.4.2  mjf static inline bool
     35  1.1.4.2  mjf ipmqisempty(ipmqindex_t ixr, ipmqindex_t ixw)
     36  1.1.4.2  mjf {
     37  1.1.4.2  mjf 	if (ixr == ixw)
     38  1.1.4.2  mjf 		return TRUE;
     39  1.1.4.2  mjf 	return FALSE;
     40  1.1.4.2  mjf }
     41  1.1.4.2  mjf 
     42  1.1.4.2  mjf static inline bool
     43  1.1.4.2  mjf ipmqisfull(ipmqindex_t ixr, ipmqindex_t ixw)
     44  1.1.4.2  mjf {
     45  1.1.4.2  mjf 	if (ipmqnext(ixw) == ixr)
     46  1.1.4.2  mjf 		return TRUE;
     47  1.1.4.2  mjf 	return FALSE;
     48  1.1.4.2  mjf }
     49  1.1.4.2  mjf 
     50  1.1.4.2  mjf #endif	/* _GEMINI_IPMVAR_H_ */
     51