freebsd-skq/sys/dev/ath/if_ath_tx_ht.h
adrian c059ecd485 Implement my first cut at "correct" node power-save and
PS-POLL support.

This implements PS-POLL awareness i nthe

* Implement frame "leaking", which allows for a software queue
  to be scheduled even though it's asleep
* Track whether a frame has been leaked or not
* Leak out a single non-AMPDU frame when transmitting aggregates
* Queue BAR frames if the node is asleep
* Direct-dispatch the rest of control and management frames.
  This allows for things like re-association to occur (which involves
  sending probe req/resp as well as assoc request/response) when
  the node is asleep and then tries reassociating.
* Limit how many frames can set in the software node queue whilst
  the node is asleep.  net80211 is already buffering frames for us
  so this is mostly just paranoia.
* Add a PS-POLL method which leaks out a frame if there's something
  in the software queue, else it calls net80211's ps-poll routine.
  Since the ath PS-POLL routine marks the node as having a single frame
  to leak, either a software queued frame would leak, OR the next queued
  frame would leak. The next queued frame could be something from the
  net80211 power save queue, OR it could be a NULL frame from net80211.

TODO:

* Don't transmit further BAR frames (eg via a timeout) if the node is
  currently asleep.  Otherwise we may end up exhausting management frames
  due to the lots of queued BAR frames.

  I may just undo this bit later on and direct-dispatch BAR frames
  even if the node is asleep.

* It would be nice to burst out a single A-MPDU frame if both ends
  support this.  I may end adding a FreeBSD IE soon to negotiate
  this power save behaviour.

* I should make STAs timeout of power save mode if they've been in power
  save for more than a handful of seconds.  This way cards that get
  "stuck" in power save mode don't stay there for the "inactivity" timeout
  in net80211.

* Move the queue depth check into the driver layer (ath_start / ath_transmit)
  rather than doing it in the TX path.

* There could be some naughty corner cases with ps-poll leaking.
  Specifically, if net80211 generates a NULL data frame whilst another
  transmitter sends a normal data frame out net80211 output / transmit,
  we need to ensure that the NULL data frame goes out first.
  This is one of those things that should occur inside the VAP/ic TX lock.
  Grr, more investigations to do..

Tested:

* STA: AR5416, AR9280
* AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00

64 lines
2.1 KiB
C

/*
* Copyright (c) 2011 Adrian Chadd, Xenion Pty Ltd.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
* redistribution must be conditioned upon including a substantially
* similar Disclaimer requirement for further binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGES.
*
* $FreeBSD$
*/
#ifndef __IF_ATH_TX_HT_H__
#define __IF_ATH_TX_HT_H__
enum {
MCS_HT20,
MCS_HT20_SGI,
MCS_HT40,
MCS_HT40_SGI,
};
typedef enum {
ATH_AGGR_DONE,
ATH_AGGR_BAW_CLOSED,
ATH_AGGR_LIMITED,
ATH_AGGR_SHORTPKT,
ATH_AGGR_8K_LIMITED,
ATH_AGGR_ERROR,
ATH_AGGR_NONAGGR,
ATH_AGGR_LEAK_CLOSED,
} ATH_AGGR_STATUS;
extern int ath_max_4ms_framelen[4][32];
extern void ath_tx_rate_fill_rcflags(struct ath_softc *sc, struct ath_buf *bf);
extern void ath_buf_set_rate(struct ath_softc *sc,
struct ieee80211_node *ni, struct ath_buf *bf);
extern ATH_AGGR_STATUS
ath_tx_form_aggr(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, ath_bufhead *bf_q);
#endif