br 8713fad4de Tune xDMA interface slightly:
o Move descriptors allocation to DMA engine driver
o Add generic xdma_request() routine
o Add less-generic scatter-gather application based on xdma interface

Typical operation flow in peripheral device driver is:

1. Get xDMA controller
sc->xdma_tx = xdma_ofw_get(sc->dev, "tx");

2. Allocate virtual channel
sc->xchan_tx = xdma_channel_alloc(sc->xdma_tx, caps);

3. Setup transfer status callback
xdma_setup_intr(sc->xchan_tx, my_tx_intr, sc, &sc->ih_tx);

4. Request a transfer(s)
ret = xdma_request(sc->xchan_tx, &req);

5. Free the channel
xdma_channel_free(sc->xdma_tx);

6. Free the controller
xdma_put(sc->xdma_tx);

Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D14971
2018-04-12 15:36:24 +00:00
..
2016-12-24 02:31:26 +00:00
2018-04-12 15:36:24 +00:00
2016-12-12 17:08:52 +00:00
2018-03-20 17:58:51 +00:00
2018-04-12 15:36:24 +00:00
2018-04-12 15:36:24 +00:00
2016-12-24 02:31:26 +00:00