path: root/drivers/net/wireless/ath/ath9k/recv.c

/*
 * Copyright (c) 2008-2009 Atheros Communications Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "ath9k.h"

static struct ieee80211_hw * ath_get_virt_hw(struct ath_softc *sc,
					     struct ieee80211_hdr *hdr)
{
	struct ieee80211_hw *hw = sc->pri_wiphy->hw;
	int i;

	spin_lock_bh(&sc->wiphy_lock);
	for (i = 0; i < sc->num_sec_wiphy; i++) {
		struct ath_wiphy *aphy = sc->sec_wiphy[i];
		if (aphy == NULL)
			continue;
		if (compare_ether_addr(hdr->addr1, aphy->hw->wiphy->perm_addr)
		    == 0) {
			hw = aphy->hw;
			break;
		}
	}
	spin_unlock_bh(&sc->wiphy_lock);
	return hw;
}

/*
 * Setup and link descriptors.
 *
 * 11N: we can no longer afford to self link the last descriptor.
 * MAC acknowledges BA status as long as it copies frames to host
 * buffer (or rx fifo). This can incorrectly acknowledge packets
 * to a sender if last desc is self-linked.
 */
static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
{
	struct ath_hw *ah = sc->sc_ah;
	struct ath_common *common = ath9k_hw_common(ah);
	struct ath_desc *ds;
	struct sk_buff *skb;

	ATH_RXBUF_RESET(bf);

	ds = bf->bf_desc;
	ds->ds_link = 0; /* link to null */
	ds->ds_data = bf->bf_buf_addr;

	/* virtual addr of the beginning of the buffer. */
	skb = bf->bf_mpdu;
	BUG_ON(skb == NULL);
	ds->ds_vdata = skb->data;

	/*
	 * setup rx descriptors. The rx_bufsize here tells the hardware
	 * how much data it can DMA to us and that we are prepared
	 * to process
	 */
	ath9k_hw_setuprxdesc(ah, ds,
			     common->rx_bufsize,
			     0);

	if (sc->rx.rxlink == NULL)
		ath9k_hw_putrxbuf(ah, bf->bf_daddr);
	else
		*sc->rx.rxlink = bf->bf_daddr;

	sc->rx.rxlink = &ds->ds_link;
	ath9k_hw_rxena(ah);
}

static void ath_setdefantenna(struct ath_softc *sc, u32 antenna)
{
	/* XXX block beacon interrupts */
	ath9k_hw_setantenna(sc->sc_ah, antenna);
	sc->rx.defant = antenna;
	sc->rx.rxotherant = 0;
}

static void ath_opmode_init(struct ath_softc *sc)
{
	struct ath_hw *ah = sc->sc_ah;
	struct ath_common *common = ath9k_hw_common(ah);

	u32 rfilt, mfilt[2];

	/* configure rx filter */
	rfilt = ath_calcrxfilter(sc);
	ath9k_hw_setrxfilter(ah, rfilt);

	/* configure bssid mask */
	if (ah->caps.hw_caps & ATH9K_HW_CAP_BSSIDMASK)
		ath_hw_setbssidmask(common);

	/* configure operational mode */
	ath9k_hw_setopmode(ah);

	/* Handle any link-level address change. */
	ath9k_hw_setmac(ah, common->macaddr);

	/* calculate and install multicast filter */
	mfilt[0] = mfilt[1] = ~0;
	ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
}

int ath_rx_init(struct ath_softc *sc, int nbufs)
{
	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
	struct sk_buff *skb;
	struct ath_buf *bf;
	int error = 0;

	spin_lock_init(&sc->rx.rxflushlock);
	sc->sc_flags &= ~SC_OP_RXFLUSH;
	spin_lock_init(&sc->rx.rxbuflock);

	common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
				     min(common->cachelsz, (u16)64));

	ath_print(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
		  common->cachelsz, common->rx_bufsize);

	/* Initialize rx descriptors */

	error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
				  "rx", nbufs, 1);
	if (error != 0) {
		ath_print(common, ATH_DBG_FATAL,
			  "failed to allocate rx descriptors: %d\n", error);
		goto err;
	}

	list_for_each_entry(bf, &sc->rx.rxbuf, list) {
		skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_KERNEL);
		if (skb == NULL) {
			error = -ENOMEM;
			goto err;
		}

		bf->bf_mpdu = skb;
		bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
						 common->rx_bufsize,
						 DMA_FROM_DEVICE);
		if (unlikely(dma_mapping_error(sc->dev,
					       bf->bf_buf_addr))) {
			dev_kfree_skb_any(skb);
			bf->bf_mpdu = NULL;
			ath_print(common, ATH_DBG_FATAL,
				  "dma_mapping_error() on RX init\n");
			error = -ENOMEM;
			goto err;
		}
		bf->bf_dmacontext = bf->bf_buf_addr;
	}
	sc->rx.rxlink = NULL;

err:
	if (error)
		ath_rx_cleanup(sc);

	return error;
}

void ath_rx_cleanup(struct ath_softc *sc)
{
	struct ath_hw *ah = sc->sc_ah;
	struct ath_common *common = ath9k_hw_common(ah);
	struct sk_buff *skb;
	struct ath_buf *bf;

	list_for_each_entry(bf, &sc->rx.rxbuf, list) {
		skb = bf->bf_mpdu;
		if (skb) {
			dma_unmap_single(sc->dev, bf->bf_buf_addr,
					 common->rx_bufsize, DMA_FROM_DEVICE);
			dev_kfree_skb(skb);
		}
	}

	if (sc->rx.rxdma.dd_desc_len != 0)
		ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
}

/*
 * Calculate the receive filter according to the
 * operating mode and state:
 *
 * o always accept unicast, broadcast, and multicast traffic
 * o maintain current state of phy error reception (the hal
 *   may enable phy error frames for noise immunity work)
 * o probe request frames are accepted only when operating in
 *   hostap, adhoc, or monitor modes
 * o enable promiscuous mode according to the interface state
 * o accept beacons:
 *   - when operating in adhoc mode so the 802.11 layer creates
 *     node table entries for peers,
 *   - when operating in station mode for collecting rssi data when
 *     the station is otherwise quiet, or
 *   - when operating as a repeater so we see repeater-sta beacons
 *   - when scanning
 */

u32 ath_calcrxfilter(struct ath_softc *sc)
{
#define	RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)

	u32 rfilt;

	rfilt = (ath9k_hw_getrxfilter(sc->sc_ah) &