184 lines
6.1 KiB
C
184 lines
6.1 KiB
C
/*
|
|
* Copyright (c) 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 <asm/unaligned.h>
|
|
|
|
#include "ath.h"
|
|
#include "reg.h"
|
|
|
|
#define REG_READ (common->ops->read)
|
|
#define REG_WRITE (common->ops->write)
|
|
|
|
/**
|
|
* ath_hw_set_bssid_mask - filter out bssids we listen
|
|
*
|
|
* @common: the ath_common struct for the device.
|
|
*
|
|
* BSSID masking is a method used by AR5212 and newer hardware to inform PCU
|
|
* which bits of the interface's MAC address should be looked at when trying
|
|
* to decide which packets to ACK. In station mode and AP mode with a single
|
|
* BSS every bit matters since we lock to only one BSS. In AP mode with
|
|
* multiple BSSes (virtual interfaces) not every bit matters because hw must
|
|
* accept frames for all BSSes and so we tweak some bits of our mac address
|
|
* in order to have multiple BSSes.
|
|
*
|
|
* NOTE: This is a simple filter and does *not* filter out all
|
|
* relevant frames. Some frames that are not for us might get ACKed from us
|
|
* by PCU because they just match the mask.
|
|
*
|
|
* When handling multiple BSSes you can get the BSSID mask by computing the
|
|
* set of ~ ( MAC XOR BSSID ) for all bssids we handle.
|
|
*
|
|
* When you do this you are essentially computing the common bits of all your
|
|
* BSSes. Later it is assumed the hardware will "and" (&) the BSSID mask with
|
|
* the MAC address to obtain the relevant bits and compare the result with
|
|
* (frame's BSSID & mask) to see if they match.
|
|
*
|
|
* Simple example: on your card you have have two BSSes you have created with
|
|
* BSSID-01 and BSSID-02. Lets assume BSSID-01 will not use the MAC address.
|
|
* There is another BSSID-03 but you are not part of it. For simplicity's sake,
|
|
* assuming only 4 bits for a mac address and for BSSIDs you can then have:
|
|
*
|
|
* \
|
|
* MAC: 0001 |
|
|
* BSSID-01: 0100 | --> Belongs to us
|
|
* BSSID-02: 1001 |
|
|
* /
|
|
* -------------------
|
|
* BSSID-03: 0110 | --> External
|
|
* -------------------
|
|
*
|
|
* Our bssid_mask would then be:
|
|
*
|
|
* On loop iteration for BSSID-01:
|
|
* ~(0001 ^ 0100) -> ~(0101)
|
|
* -> 1010
|
|
* bssid_mask = 1010
|
|
*
|
|
* On loop iteration for BSSID-02:
|
|
* bssid_mask &= ~(0001 ^ 1001)
|
|
* bssid_mask = (1010) & ~(0001 ^ 1001)
|
|
* bssid_mask = (1010) & ~(1000)
|
|
* bssid_mask = (1010) & (0111)
|
|
* bssid_mask = 0010
|
|
*
|
|
* A bssid_mask of 0010 means "only pay attention to the second least
|
|
* significant bit". This is because its the only bit common
|
|
* amongst the MAC and all BSSIDs we support. To findout what the real
|
|
* common bit is we can simply "&" the bssid_mask now with any BSSID we have
|
|
* or our MAC address (we assume the hardware uses the MAC address).
|
|
*
|
|
* Now, suppose there's an incoming frame for BSSID-03:
|
|
*
|
|
* IFRAME-01: 0110
|
|
*
|
|
* An easy eye-inspeciton of this already should tell you that this frame
|
|
* will not pass our check. This is because the bssid_mask tells the
|
|
* hardware to only look at the second least significant bit and the
|
|
* common bit amongst the MAC and BSSIDs is 0, this frame has the 2nd LSB
|
|
* as 1, which does not match 0.
|
|
*
|
|
* So with IFRAME-01 we *assume* the hardware will do:
|
|
*
|
|
* allow = (IFRAME-01 & bssid_mask) == (bssid_mask & MAC) ? 1 : 0;
|
|
* --> allow = (0110 & 0010) == (0010 & 0001) ? 1 : 0;
|
|
* --> allow = (0010) == 0000 ? 1 : 0;
|
|
* --> allow = 0
|
|
*
|
|
* Lets now test a frame that should work:
|
|
*
|
|
* IFRAME-02: 0001 (we should allow)
|
|
*
|
|
* allow = (IFRAME-02 & bssid_mask) == (bssid_mask & MAC) ? 1 : 0;
|
|
* --> allow = (0001 & 0010) == (0010 & 0001) ? 1 :0;
|
|
* --> allow = (0000) == (0000)
|
|
* --> allow = 1
|
|
*
|
|
* Other examples:
|
|
*
|
|
* IFRAME-03: 0100 --> allowed
|
|
* IFRAME-04: 1001 --> allowed
|
|
* IFRAME-05: 1101 --> allowed but its not for us!!!
|
|
*
|
|
*/
|
|
void ath_hw_setbssidmask(struct ath_common *common)
|
|
{
|
|
void *ah = common->ah;
|
|
|
|
REG_WRITE(ah, get_unaligned_le32(common->bssidmask), AR_BSSMSKL);
|
|
REG_WRITE(ah, get_unaligned_le16(common->bssidmask + 4), AR_BSSMSKU);
|
|
}
|
|
EXPORT_SYMBOL(ath_hw_setbssidmask);
|
|
|
|
|
|
/**
|
|
* ath_hw_cycle_counters_update - common function to update cycle counters
|
|
*
|
|
* @common: the ath_common struct for the device.
|
|
*
|
|
* This function is used to update all cycle counters in one place.
|
|
* It has to be called while holding common->cc_lock!
|
|
*/
|
|
void ath_hw_cycle_counters_update(struct ath_common *common)
|
|
{
|
|
u32 cycles, busy, rx, tx;
|
|
void *ah = common->ah;
|
|
|
|
/* freeze */
|
|
REG_WRITE(ah, AR_MIBC_FMC, AR_MIBC);
|
|
|
|
/* read */
|
|
cycles = REG_READ(ah, AR_CCCNT);
|
|
busy = REG_READ(ah, AR_RCCNT);
|
|
rx = REG_READ(ah, AR_RFCNT);
|
|
tx = REG_READ(ah, AR_TFCNT);
|
|
|
|
/* clear */
|
|
REG_WRITE(ah, 0, AR_CCCNT);
|
|
REG_WRITE(ah, 0, AR_RFCNT);
|
|
REG_WRITE(ah, 0, AR_RCCNT);
|
|
REG_WRITE(ah, 0, AR_TFCNT);
|
|
|
|
/* unfreeze */
|
|
REG_WRITE(ah, 0, AR_MIBC);
|
|
|
|
/* update all cycle counters here */
|
|
common->cc_ani.cycles += cycles;
|
|
common->cc_ani.rx_busy += busy;
|
|
common->cc_ani.rx_frame += rx;
|
|
common->cc_ani.tx_frame += tx;
|
|
|
|
common->cc_survey.cycles += cycles;
|
|
common->cc_survey.rx_busy += busy;
|
|
common->cc_survey.rx_frame += rx;
|
|
common->cc_survey.tx_frame += tx;
|
|
}
|
|
EXPORT_SYMBOL(ath_hw_cycle_counters_update);
|
|
|
|
int32_t ath_hw_get_listen_time(struct ath_common *common)
|
|
{
|
|
struct ath_cycle_counters *cc = &common->cc_ani;
|
|
int32_t listen_time;
|
|
|
|
listen_time = (cc->cycles - cc->rx_frame - cc->tx_frame) /
|
|
(common->clockrate * 1000);
|
|
|
|
memset(cc, 0, sizeof(*cc));
|
|
|
|
return listen_time;
|
|
}
|
|
EXPORT_SYMBOL(ath_hw_get_listen_time);
|