[3ae31e9] | 1 | /*
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| 2 | =============================================================================
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| 3 | mtsett.c -- Multi-Tasker -- task initialization with a new TCB
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| 4 | Version 1 -- 1988-04-11 -- D.N. Lynx Crowe
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| 5 | (c) Copyright 1988 -- D.N. Lynx Crowe
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| 6 | =============================================================================
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| 7 | */
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| 8 |
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| 9 | #include "stddefs.h"
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| 10 | #include "biosdefs.h"
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| 11 | #include "mtdefs.h"
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| 12 | #include "debug.h"
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| 13 |
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| 14 | extern short setipl(); /* set processor IPL function */
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| 15 | extern short MTExit(); /* task terminate function */
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| 16 |
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| 17 | extern struct _mtdef *_MT_; /* Multi-Tasker structure pointer */
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| 18 |
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| 19 | /* |
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| 20 |
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| 21 | */
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| 22 |
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| 23 | /*
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| 24 | =============================================================================
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| 25 | MTSetT() -- initialize a TCB
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| 26 | =============================================================================
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| 27 | */
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| 28 |
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| 29 | MTSetT(tcp, tid, pri, stat, slice, pstack, func, par)
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| 30 | register TCB *tcp;
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| 31 | unsigned tid;
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| 32 | register unsigned pri;
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| 33 | unsigned stat;
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| 34 | long slice, pstack;
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| 35 | short (*func)();
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| 36 | long par;
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| 37 | {
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| 38 | register short oldipl;
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| 39 | register TCB *rcur, *rprv;
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| 40 |
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| 41 | DB_ENTR("MTSetT");
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| 42 |
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| 43 | if ((struct _mt_def *)NIL EQ _MT_)
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| 44 | _MT_ = (struct _mt_def *)XBIOS(X_MTDEFS);
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| 45 |
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| 46 | oldipl = setipl(7); /* DISABLE INTERRUPTS */
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| 47 |
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| 48 | /* setup the TCB */
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| 49 |
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| 50 | tcp->tos = pstack; /* put top of stack in TCB */
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| 51 |
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| 52 | pstack -= 4L; /* adjust stack pointer */
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| 53 | *(long *)pstack = par; /* store task parameter */
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| 54 |
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| 55 | pstack -= 4L; /* adjust stack pointer */
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| 56 | *(long *)pstack = MTExit; /* store return address */
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| 57 |
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| 58 | tcp->flags = MTF_OCC; /* flags = TCB occupied */
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| 59 | tcp->tid = tid; /* ID */
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| 60 | tcp->pri = pri; /* priority */
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| 61 | tcp->slice = slice; /* time slice */
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| 62 | tcp->sp = pstack; /* stack pointer */
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| 63 | tcp->reg[15] = pstack; /* a7 */
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| 64 | tcp->pc = func; /* program counter */
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| 65 | tcp->sr = stat; /* status register */
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| 66 |
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| 67 | /* |
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| 68 |
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| 69 | */
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| 70 | /* queue the TCB */
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| 71 |
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| 72 | rcur = (TCB *)&_MT_->mtp->RdyQ; /* point at the head of the queue */
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| 73 |
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| 74 | while (TRUE) {
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| 75 |
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| 76 | rprv = rcur; /* previous TCB = current TCB */
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| 77 | rcur = rprv->next; /* current TCB = next TCB */
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| 78 |
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| 79 | if (rcur EQ (TCB *)NIL) /* enqueue here if next was NIL */
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| 80 | break;
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| 81 |
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| 82 | if (pri > rcur->pri) /* enqueue here if priority is greater */
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| 83 | break;
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| 84 | }
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| 85 |
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| 86 | rprv->next = tcp; /* set next of previous TCB to new TCB */
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| 87 | tcp->next = rcur; /* set next of new TCB to old next */
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| 88 | tcp->flags |= MTF_RDY; /* set the ready flag in the new TCB */
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| 89 |
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| 90 | tcp->fwd = _MT_->mtp->TCBs; /* add TCB to chain */
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| 91 | _MT_->mtp->TCBs = tcp; /* ... */
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| 92 |
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| 93 | setipl(oldipl); /* RESTORE INTERUPTS */
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| 94 | DB_EXIT("MTSetT");
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| 95 | }
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