wireless/ath/hw.c

23 #define REG_READ			(common->ops->read)
24 #define REG_WRITE(_ah, _reg, _val)	(common->ops->write)(_ah, _val, _reg)
27  * ath_hw_setbssidmask - filter out bssids we listen
32  * which bits of the interface's MAC address should be looked at when trying
34  * BSS every bit matters since we lock to only one BSS. In AP mode with
36  * accept frames for all BSSes and so we tweak some bits of our mac address
44  * set of  ~ ( MAC XOR BSSID ) for all bssids we handle.
48  * the MAC address to obtain the relevant bits and compare the result with
52  * BSSID-01 and BSSID-02. Lets assume BSSID-01 will not use the MAC address.
53  * There is another BSSID-03 but you are not part of it. For simplicity's sake,
54  * assuming only 4 bits for a mac address and for BSSIDs you can then have:
57  * MAC:        0001 |
58  * BSSID-01:   0100 | --> Belongs to us
59  * BSSID-02:   1001 |
61  * -------------------
62  * BSSID-03:   0110  | --> External
63  * -------------------
67  *             On loop iteration for BSSID-01:
68  *             ~(0001 ^ 0100)  -> ~(0101)
69  *                             ->   1010
72  *             On loop iteration for BSSID-02:
79  * A bssid_mask of 0010 means "only pay attention to the second least
80  * significant bit". This is because its the only bit common
81  * amongst the MAC and all BSSIDs we support. To findout what the real
83  * or our MAC address (we assume the hardware uses the MAC address).
85  * Now, suppose there's an incoming frame for BSSID-03:
87  * IFRAME-01:  0110
89  * An easy eye-inspeciton of this already should tell you that this frame
91  * hardware to only look at the second least significant bit and the
92  * common bit amongst the MAC and BSSIDs is 0, this frame has the 2nd LSB
95  * So with IFRAME-01 we *assume* the hardware will do:
97  *     allow = (IFRAME-01 & bssid_mask) == (bssid_mask & MAC) ? 1 : 0;
98  *  --> allow = (0110 & 0010) == (0010 & 0001) ? 1 : 0;
99  *  --> allow = (0010) == 0000 ? 1 : 0;
100  *  --> allow = 0
104  * IFRAME-02:  0001 (we should allow)
106  *     allow = (IFRAME-02 & bssid_mask) == (bssid_mask & MAC) ? 1 : 0;
107  *  --> allow = (0001 & 0010) ==  (0010 & 0001) ? 1 :0;
108  *  --> allow = (0000) == (0000)
109  *  --> allow = 1
113  * IFRAME-03:  0100 --> allowed
114  * IFRAME-04:  1001 --> allowed
115  * IFRAME-05:  1101 --> allowed but its not for us!!!
120 	void *ah = common->ah;  in ath_hw_setbssidmask()
123 	REG_WRITE(ah, AR_STA_ID0, get_unaligned_le32(common->macaddr));  in ath_hw_setbssidmask()
125 	id1 |= get_unaligned_le16(common->macaddr + 4);  in ath_hw_setbssidmask()
128 	REG_WRITE(ah, AR_BSSMSKL, get_unaligned_le32(common->bssidmask));  in ath_hw_setbssidmask()
129 	REG_WRITE(ah, AR_BSSMSKU, get_unaligned_le16(common->bssidmask + 4));  in ath_hw_setbssidmask()
135  * ath_hw_cycle_counters_update - common function to update cycle counters
140  * It has to be called while holding common->cc_lock!
145 	void *ah = common->ah;  in ath_hw_cycle_counters_update()
166 	common->cc_ani.cycles += cycles;  in ath_hw_cycle_counters_update()
167 	common->cc_ani.rx_busy += busy;  in ath_hw_cycle_counters_update()
168 	common->cc_ani.rx_frame += rx;  in ath_hw_cycle_counters_update()
169 	common->cc_ani.tx_frame += tx;  in ath_hw_cycle_counters_update()
171 	common->cc_survey.cycles += cycles;  in ath_hw_cycle_counters_update()
172 	common->cc_survey.rx_busy += busy;  in ath_hw_cycle_counters_update()
173 	common->cc_survey.rx_frame += rx;  in ath_hw_cycle_counters_update()
174 	common->cc_survey.tx_frame += tx;  in ath_hw_cycle_counters_update()
180 	struct ath_cycle_counters *cc = &common->cc_ani;  in ath_hw_get_listen_time()
183 	listen_time = (cc->cycles - cc->rx_frame - cc->tx_frame) /  in ath_hw_get_listen_time()
184 		      (common->clockrate * 1000);  in ath_hw_get_listen_time()