diff options
Diffstat (limited to 'sys/arch/hp300/dev/dma.c')
| -rw-r--r-- | sys/arch/hp300/dev/dma.c | 39 |
1 files changed, 32 insertions, 7 deletions
diff --git a/sys/arch/hp300/dev/dma.c b/sys/arch/hp300/dev/dma.c index 17820334441..ebfa5901534 100644 --- a/sys/arch/hp300/dev/dma.c +++ b/sys/arch/hp300/dev/dma.c @@ -1,7 +1,8 @@ -/* $NetBSD: dma.c,v 1.7 1996/02/14 02:44:17 thorpej Exp $ */ +/* $OpenBSD: dma.c,v 1.4 1997/01/12 15:12:28 downsj Exp $ */ +/* $NetBSD: dma.c,v 1.10 1996/12/09 03:09:51 thorpej Exp $ */ /* - * Copyright (c) 1995 Jason R. Thorpe. + * Copyright (c) 1995, 1996 Jason R. Thorpe. All rights reserved. * Copyright (c) 1982, 1990, 1993 * The Regents of the University of California. All rights reserved. * @@ -54,7 +55,6 @@ #include <hp300/hp300/isr.h> -extern void isrlink(); extern void _insque(); extern void _remque(); extern u_int kvtop(); @@ -89,6 +89,8 @@ struct dma_softc { struct dmareg *sc_dmareg; /* pointer to our hardware */ struct dma_channel sc_chan[NDMACHAN]; /* 2 channels */ char sc_type; /* A, B, or C */ + int sc_ipl; /* our interrupt level */ + void *sc_ih; /* interrupt cookie */ } Dma_softc; /* types */ @@ -140,7 +142,7 @@ dmainit() * * XXX Don't know how to easily differentiate the A and B cards, * so we just hope nobody has an A card (A cards will work if - * DMAINTLVL is set to 3). + * splbio works out to ipl 3). */ if (badbaddr((char *)&dma->dma_id[2])) { rev = 'B'; @@ -181,8 +183,31 @@ dmainit() printf("%s: 98620%c, 2 channels, %d bit\n", sc->sc_xname, rev, (rev == 'B') ? 16 : 32); - /* Establish the interrupt handler */ - isrlink(dmaintr, sc, DMAINTLVL, ISRPRI_BIO); + /* + * Defer hooking up our interrupt until the first + * DMA-using controller has hooked up theirs. + */ + sc->sc_ih = NULL; +} + +/* + * Compute the ipl and (re)establish the interrupt handler + * for the DMA controller. + */ +void +dmacomputeipl() +{ + struct dma_softc *sc = &Dma_softc; + + if (sc->sc_ih != NULL) + isrunlink(sc->sc_ih); + + /* + * Our interrupt level must be as high as the highest + * device using DMA (i.e. splbio). + */ + sc->sc_ipl = PSLTOIPL(hp300_bioipl); + sc->sc_ih = isrlink(dmaintr, sc, sc->sc_ipl, ISRPRI_BIO); } int @@ -342,7 +367,7 @@ dmago(unit, addr, count, flags) /* * Set up the command word based on flags */ - dc->dm_cmd = DMA_ENAB | DMA_IPL(DMAINTLVL) | DMA_START; + dc->dm_cmd = DMA_ENAB | DMA_IPL(sc->sc_ipl) | DMA_START; if ((flags & DMAGO_READ) == 0) dc->dm_cmd |= DMA_WRT; if (flags & DMAGO_LWORD) |