Function bcm_dma_attach

freebsd/arm/broadcom/bcm2835/bcm2835_dma.c:672–753

}

static int
bcm_dma_attach(device_t dev)
{
	struct bcm_dma_softc *sc = device_get_softc(dev);
	phandle_t node;
	int rid, err = 0;
	int i;

	sc->sc_dev = dev;

	if (bcm_dma_sc)
		return (ENXIO);

	for (i = 0; i < BCM_DMA_CH_MAX; i++) {
		sc->sc_irq[i] = NULL;
		sc->sc_intrhand[i] = NULL;
	}

	/* Get DMA channel mask. */
	node = ofw_bus_get_node(sc->sc_dev);
	if (OF_getencprop(node, "brcm,dma-channel-mask", &bcm_dma_channel_mask,
	    sizeof(bcm_dma_channel_mask)) == -1 &&
	    OF_getencprop(node, "broadcom,channels", &bcm_dma_channel_mask,
	    sizeof(bcm_dma_channel_mask)) == -1) {
		device_printf(dev, "could not get channel mask property\n");
		return (ENXIO);
	}

	/* Mask out channels used by GPU. */
	bcm_dma_channel_mask &= ~BCM_DMA_CH_GPU_MASK;

	/* DMA0 - DMA14 */
	rid = 0;
	sc->sc_mem = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
	if (sc->sc_mem == NULL) {
		device_printf(dev, "could not allocate memory resource\n");
		return (ENXIO);
	}

	/* IRQ DMA0 - DMA11 XXX NOT USE DMA12(spurious?) */
	for (rid = 0; rid < BCM_DMA_CH_MAX; rid++) {
		if ((bcm_dma_channel_mask & (1 << rid)) == 0)
			continue;

		sc->sc_irq[rid] = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
		    RF_ACTIVE | RF_SHAREABLE);
		if (sc->sc_irq[rid] == NULL) {
			device_printf(dev, "cannot allocate interrupt\n");
			err = ENXIO;
			goto fail;
		}
		if (bus_setup_intr(dev, sc->sc_irq[rid], INTR_TYPE_MISC | INTR_MPSAFE,
				   NULL, bcm_dma_intr, &sc->sc_dma_ch[rid],
				   &sc->sc_intrhand[rid])) {
			device_printf(dev, "cannot setup interrupt handler\n");
			err = ENXIO;
			goto fail;
		}