ref: 6b84c3a6548f1c577948763b0a09a7b6e2460e04
dir: /os/mpc/dsp.c/
/* * DSP support functions */ #include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" #include "io.h" #include "dsp.h" enum { Ndsp = 2, /* determined by hardware */ NHOLES= 64 }; typedef struct DSPparam DSPparam; struct DSPparam { ulong fdbase; /* function descriptor table physical base address */ ulong fd_ptr; /* function descriptor pointer */ ulong dstate; /* DSP state */ ulong resvd[2]; ushort dstatus; /* current function descriptor status */ ushort i; /* number of iterations */ ushort tap; /* number of TAPs */ ushort cbase; ushort anon1; /* sample buffer size-1 */ ushort xptr; /* pointer to sample */ ushort anon2; /* output buffer size-1 */ ushort yptr; /* pointer to output */ ushort m; /* sample buffer size-1 */ ushort anon3; /* sample buffer pointer */ ushort n; /* output buffer size -1 */ ushort anon4; /* output buffer pointer */ ushort k; /* coefficient buffer size - 1 */ ushort anon5; /* coefficient buffer pointer */ }; struct DSP { Lock; /* protects state */ void (*done)(void*); void* arg; DSPparam* par; CPMdev* cpm; QLock; /* protects busyr */ int busy; Rendez busyr; }; static DSP dsps[Ndsp]; static Lock dsplock; static int dspinit; static struct { QLock; ulong avail; Rendez wantr; } dspalloc; static Map fndmapv[NHOLES]; static RMap fndmap = {"DSP function descriptors"}; static void dspinterrupt(Ureg*, void*) { int i; ushort events; DSP *dsp; events = m->iomem->sdsr; m->iomem->sdsr = events; if(events & (1<<7)) panic("dsp: SDMA channel bus error sdar=#%lux", m->iomem->sdar); for(i=0; i<Ndsp; i++) if(events & (1<<i)){ dsp = &dsps[i]; if(dsp->busy){ dsp->busy = 0; if(dsp->done) dsp->done(dsp->arg); else wakeup(&dsp->busyr); }else print("dsp%d: empty interrupt\n", i); } } /* * called by system initialisation to set up the DSPs */ void dspinitialise(void) { CPMdev *d; ilock(&dsplock); if(dspinit == 0){ mapinit(&fndmap, fndmapv, sizeof(fndmapv)); d = cpmdev(CPdsp1); dsps[0].cpm = d; dsps[0].par = d->param; d = cpmdev(CPdsp2); dsps[1].cpm = d; dsps[1].par = d->param; intrenable(VectorCPIC+d->irq, dspinterrupt, nil, BUSUNKNOWN, "dsp"); dspalloc.avail = (1<<Ndsp)-1; dspinit = 1; } iunlock(&dsplock); } static int dspavail(void*) { return dspalloc.avail != 0; } /* * wait for a DSP to become available, and return a reference to it. * if done is not nil, it will be called (with the given arg) when that * DSP completes each function (if set to interrupt). */ DSP* dspacquire(void (*done)(void*), void *arg) { DSP *dsp; int i; if(dspinit == 0) dspinitialise(); qlock(&dspalloc); if(waserror()){ qunlock(&dspalloc); nexterror(); } for(i=0;; i++){ if(i >= Ndsp){ sleep(&dspalloc.wantr, dspavail, nil); i = 0; } if(dspalloc.avail & (1<<i)) break; } dsp = &dsps[i]; if(dsp->busy) panic("dspacquire"); dsp->done = done; dsp->arg = arg; poperror(); qunlock(&dspalloc); return dsp; } /* * relinquish access to the given DSP */ void dsprelease(DSP *dsp) { ulong bit; if(dsp == nil) return; bit = 1 << (dsp-dsps); if(dspalloc.avail & bit) panic("dsprelease"); dspalloc.avail |= bit; wakeup(&dspalloc.wantr); } /* * execute f[0] to f[n-1] on the given DSP */ void dspexec(DSP *dsp, FnD *f, ulong n) { dspsetfn(dsp, f, n); dspstart(dsp); } /* * set the DSP to execute f[0] to f[n-1] */ void dspsetfn(DSP *dsp, FnD *f, ulong n) { f[n-1].status |= FnWrap; ilock(dsp); dsp->par->fdbase = PADDR(f); iunlock(dsp); cpmop(dsp->cpm, InitDSP, 0); } /* * start execution of the preset function(s) */ void dspstart(DSP *dsp) { ilock(dsp); dsp->busy = 1; iunlock(dsp); cpmop(dsp->cpm, StartDSP, 0); } static int dspdone(void *a) { return ((DSP*)a)->busy; } /* * wait until the DSP has completed execution */ void dspsleep(DSP *dsp) { sleep(&dsp->busyr, dspdone, dsp); } /* * allocate n function descriptors */ FnD* fndalloc(ulong n) { ulong a, nb, pgn; FnD *f; if(n == 0) return nil; if(dspinit == 0) dspinitialise(); nb = n*sizeof(FnD); while((a = rmapalloc(&fndmap, 0, nb, sizeof(FnD))) != 0){ /* expected to loop just once, but might lose a race with another dsp user */ pgn = (nb+BY2PG-1)&~(BY2PG-1); a = PADDR(xspanalloc(pgn, sizeof(FnD), 0)); if(a == 0) return nil; mapfree(&fndmap, a, pgn); } f = KADDR(a); f[n-1].status = FnWrap; return f; } /* * free n function descriptors */ void fndfree(FnD *f, ulong n) { if(f != nil) mapfree(&fndmap, PADDR(f), n*sizeof(FnD)); } /* * allocate an IO buffer region in shared memory for use by the DSP */ void* dspmalloc(ulong n) { ulong i; n = (n+3)&~4; i = n; if(n & (n-1)){ /* align on a power of two */ for(i=1; i < n; i <<= 1) ; } return cpmalloc(n, i); /* this seems to be what 16.3.3.2 is trying to say */ } /* * free DSP buffer memory */ void dspfree(void *p, ulong n) { if(p != nil) cpmfree(p, (n+3)&~4); }