- 根目录:
- drivers
- net
- wireless
- iwlwifi
- mvm
- rx.c
/******************************************************************************
*
* This file is provided under a dual BSD/GPLv2 license. When using or
* redistributing this file, you may do so under either license.
*
* GPL LICENSE SUMMARY
*
* Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
* USA
*
* The full GNU General Public License is included in this distribution
* in the file called COPYING.
*
* Contact Information:
* Intel Linux Wireless <ilw@linux.intel.com>
* Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
*
* BSD LICENSE
*
* Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* 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 MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* 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 DAMAGE.
*****************************************************************************/
#include "iwl-trans.h"
#include "mvm.h"
#include "fw-api.h"
/*
* iwl_mvm_rx_rx_phy_cmd - REPLY_RX_PHY_CMD handler
*
* Copies the phy information in mvm->last_phy_info, it will be used when the
* actual data will come from the fw in the next packet.
*/
int iwl_mvm_rx_rx_phy_cmd(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
struct iwl_device_cmd *cmd)
{
struct iwl_rx_packet *pkt = rxb_addr(rxb);
memcpy(&mvm->last_phy_info, pkt->data, sizeof(mvm->last_phy_info));
mvm->ampdu_ref++;
return 0;
}
/*
* iwl_mvm_pass_packet_to_mac80211 - builds the packet for mac80211
*
* Adds the rxb to a new skb and give it to mac80211
*/
static void iwl_mvm_pass_packet_to_mac80211(struct iwl_mvm *mvm,
struct ieee80211_hdr *hdr, u16 len,
u32 ampdu_status,
struct iwl_rx_cmd_buffer *rxb,
struct ieee80211_rx_status *stats)
{
struct sk_buff *skb;
unsigned int hdrlen, fraglen;
/* Dont use dev_alloc_skb(), we'll have enough headroom once
* ieee80211_hdr pulled.
*/
skb = alloc_skb(128, GFP_ATOMIC);
if (!skb) {
IWL_ERR(mvm, "alloc_skb failed\n");
return;
}
/* If frame is small enough to fit in skb->head, pull it completely.
* If not, only pull ieee80211_hdr so that splice() or TCP coalesce
* are more efficient.
*/
hdrlen = (len <= skb_tailroom(skb)) ? len : sizeof(*hdr);
memcpy(skb_put(skb, hdrlen), hdr, hdrlen);
fraglen = len - hdrlen;
if (fraglen) {
int offset = (void *)hdr + hdrlen -
rxb_addr(rxb) + rxb_offset(rxb);
skb_add_rx_frag(skb, 0, rxb_steal_page(rxb), offset,
fraglen, rxb->truesize);
}
memcpy(IEEE80211_SKB_RXCB(skb), stats, sizeof(*stats));
ieee80211_rx_ni(mvm->hw, skb);
}
/*
* iwl_mvm_calc_rssi - calculate the rssi in dBm
* @phy_info: the phy information for the coming packet
*/
static int iwl_mvm_calc_rssi(struct iwl_mvm *mvm,
struct iwl_rx_phy_info *phy_info)
{
int rssi_a, rssi_b, rssi_a_dbm, rssi_b_dbm, max_rssi_dbm;
int rssi_all_band_a, rssi_all_band_b;
u32 agc_a, agc_b, max_agc;
u32 val;
/* Find max rssi among 2 possible receivers.
* These values are measured by the Digital Signal Processor (DSP).
* They should stay fairly constant even as the signal strength varies,
* if the radio's Automatic Gain Control (AGC) is working right.
* AGC value (see below) will provide the "interesting" info.
*/
val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_AGC_IDX]);
agc_a = (val & IWL_OFDM_AGC_A_MSK) >> IWL_OFDM_AGC_A_POS;
agc_b = (val & IWL_OFDM_AGC_B_MSK) >> IWL_OFDM_AGC_B_POS;
max_agc = max_t(u32, agc_a, agc_b);
val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_RSSI_AB_IDX]);
rssi_a = (val & IWL_OFDM_RSSI_INBAND_A_MSK) >> IWL_OFDM_RSSI_A_POS;
rssi_b = (val & IWL_OFDM_RSSI_INBAND_B_MSK) >> IWL_OFDM_RSSI_B_POS;
rssi_all_band_a = (val & IWL_OFDM_RSSI_ALLBAND_A_MSK) >>
IWL_OFDM_RSSI_ALLBAND_A_POS;
rssi_all_band_b = (val & IWL_OFDM_RSSI_ALLBAND_B_MSK) >>
IWL_OFDM_RSSI_ALLBAND_B_POS;
/*
* dBm = rssi dB - agc dB - constant.
* Higher AGC (higher radio gain) means lower signal.
*/
rssi_a_dbm = rssi_a - IWL_RSSI_OFFSET - agc_a;
rssi_b_dbm = rssi_b - IWL_RSSI_OFFSET - agc_b;
max_rssi_dbm = max_t(int, rssi_a_dbm, rssi_b_dbm);
IWL_DEBUG_STATS(mvm, "Rssi In A %d B %d Max %d AGCA %d AGCB %d\n",
rssi_a_dbm, rssi_b_dbm, max_rssi_dbm, agc_a, agc_b);
return max_rssi_dbm;
}
/*
* iwl_mvm_set_mac80211_rx_flag - translate fw status to mac80211 format
* @mvm: the mvm object
* @hdr: 80211 header
* @stats: status in mac80211's format
* @rx_pkt_status: status coming from fw
*
* returns non 0 value if the packet should be dropped
*/
static u32 iwl_mvm_set_mac80211_rx_flag(struct iwl_mvm *mvm,
struct ieee80211_hdr *hdr,
struct ieee80211_rx_status *stats,
u32 rx_pkt_status)
{
if (!ieee80211_has_protected(hdr->frame_control) ||
(rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) ==
RX_MPDU_RES_STATUS_SEC_NO_ENC)
return 0;
/* packet was encrypted with unknown alg */
if ((rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) ==
RX_MPDU_RES_STATUS_SEC_ENC_ERR)
return 0;
switch (rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) {
case RX_MPDU_RES_STATUS_SEC_CCM_ENC:
/* alg is CCM: check MIC only */
if (!(rx_pkt_status & RX_MPDU_RES_STATUS_MIC_OK))
return -1;
stats->flag |= RX_FLAG_DECRYPTED;
IWL_DEBUG_WEP(mvm, "hw decrypted CCMP successfully\n");
return 0;
case RX_MPDU_RES_STATUS_SEC_TKIP_ENC:
/* Don't drop the frame and decrypt it in SW */
if (!(rx_pkt_status & RX_MPDU_RES_STATUS_TTAK_OK))
return 0;
/* fall through if TTAK OK */
case RX_MPDU_RES_STATUS_SEC_WEP_ENC:
if (!(rx_pkt_status & RX_MPDU_RES_STATUS_ICV_OK))
return -1;
stats->flag |= RX_FLAG_DECRYPTED;
return 0;
default:
IWL_ERR(mvm, "Unhandled alg: 0x%x\n", rx_pkt_status);
}
return 0;
}
/*
* iwl_mvm_rx_rx_mpdu - REPLY_RX_MPDU_CMD handler
*
* Handles the actual data of the Rx packet from the fw
*/
int iwl_mvm_rx_rx_mpdu(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
struct iwl_device_cmd *cmd)
{
struct ieee80211_hdr *hdr;
struct ieee80211_rx_status rx_status = {};
struct iwl_rx_packet *pkt = rxb_addr(rxb);
struct iwl_rx_phy_info *phy_info;
struct iwl_rx_mpdu_res_start *rx_res;
u32 len;
u32 ampdu_status;
u32 rate_n_flags;
u32 rx_pkt_status;
phy_info = &mvm->last_phy_info;
rx_res = (struct iwl_rx_mpdu_res_start *)pkt->data;
hdr = (struct ieee80211_hdr *)(pkt->data + sizeof(*rx_res));
len = le16_to_cpu(rx_res->byte_count);
rx_pkt_status = le32_to_cpup((__le32 *)
(pkt->data + sizeof(*rx_res) + len));
memset(&rx_status, 0, sizeof(rx_status));
/*
* drop the packet if it has failed being decrypted by HW
*/
if (iwl_mvm_set_mac80211_rx_flag(mvm, hdr, &rx_status, rx_pkt_status)) {
IWL_DEBUG_DROP(mvm, "Bad decryption results 0x%08x\n",
rx_pkt_status);
return 0;
}
if ((unlikely(phy_info->cfg_phy_cnt > 20))) {
IWL_DEBUG_DROP(mvm, "dsp size out of range [0,20]: %d\n",
phy_info->cfg_phy_cnt);
return 0;
}
if (!(rx_pkt_status & RX_MPDU_RES_STATUS_CRC_OK) ||
!(rx_pkt_status & RX_MPDU_RES_STATUS_OVERRUN_OK)) {
IWL_DEBUG_RX(mvm, "Bad CRC or FIFO: 0x%08X.\n", rx_pkt_status);
return 0;
}
/* This will be used in several places later */
rate_n_flags = le32_to_cpu(phy_info->rate_n_flags);
/* rx_status carries information about the packet to mac80211 */
rx_status.mactime = le64_to_cpu(phy_info->timestamp);
rx_status.device_timestamp = le32_to_cpu(phy_info->system_timestamp);
rx_status.band =
(phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_BAND_24)) ?
IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
rx_status.freq =
ieee80211_channel_to_frequency(le16_to_cpu(phy_info->channel),
rx_status.band);
/*
* TSF as indicated by the fw is at INA time, but mac80211 expects the
* TSF at the beginning of the MPDU.
*/
/*rx_status.flag |= RX_FLAG_MACTIME_MPDU;*/
/* Find max signal strength (dBm) among 3 antenna/receiver chains */
rx_status.signal = iwl_mvm_calc_rssi(mvm, phy_info);
IWL_DEBUG_STATS_LIMIT(mvm, "Rssi %d, TSF %llu\n", rx_status.signal,
(unsigned long long)rx_status.mactime);
/*
* "antenna number"
*
* It seems that the antenna field in the phy flags value
* is actually a bit field. This is undefined by radiotap,
* it wants an actual antenna number but I always get "7"
* for most legacy frames I receive indicating that the
* same frame was received on all three RX chains.
*
* I think this field should be removed in favor of a
* new 802.11n radiotap field "RX chains" that is defined
* as a bitmask.
*/
rx_status.antenna = (le16_to_cpu(phy_info->phy_flags) &
RX_RES_PHY_FLAGS_ANTENNA)
>> RX_RES_PHY_FLAGS_ANTENNA_POS;
/* set the preamble flag if appropriate */
if (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_SHORT_PREAMBLE))
rx_status.flag |= RX_FLAG_SHORTPRE;
if (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_AGG)) {
/*
* We know which subframes of an A-MPDU belong
* together since we get a single PHY response
* from the firmware for all of them
*/
rx_status.flag |= RX_FLAG_AMPDU_DETAILS;
rx_status.ampdu_reference = mvm->ampdu_ref;
}
/* Set up the HT phy flags */
switch (rate_n_flags & RATE_MCS_CHAN_WIDTH_MSK) {
case RATE_MCS_CHAN_WIDTH_20:
break;
case RATE_MCS_CHAN_WIDTH_40:
rx_status.flag |= RX_FLAG_40MHZ;
break;
case RATE_MCS_CHAN_WIDTH_80:
rx_status.flag |= RX_FLAG_80MHZ;
break;
case RATE_MCS_CHAN_WIDTH_160:
rx_status.flag |= RX_FLAG_160MHZ;
break;
}
if (rate_n_flags & RATE_MCS_SGI_MSK)
rx_status.flag |= RX_FLAG_SHORT_GI;
if (rate_n_flags & RATE_HT_MCS_GF_MSK)
rx_status.flag |= RX_FLAG_HT_GF;
if (rate_n_flags & RATE_MCS_HT_MSK) {
rx_status.flag |= RX_FLAG_HT;
rx_status.rate_idx = rate_n_flags & RATE_HT_MCS_INDEX_MSK;
} else if (rate_n_flags & RATE_MCS_VHT_MSK) {
rx_status.vht_nss =
((rate_n_flags & RATE_VHT_MCS_NSS_MSK) >>
RATE_VHT_MCS_NSS_POS) + 1;
rx_status.rate_idx = rate_n_flags & RATE_VHT_MCS_RATE_CODE_MSK;
rx_status.flag |= RX_FLAG_VHT;
} else {
rx_status.rate_idx =
iwl_mvm_legacy_rate_to_mac80211_idx(rate_n_flags,
rx_status.band);
}
iwl_mvm_pass_packet_to_mac80211(mvm, hdr, len, ampdu_status,
rxb, &rx_status);
return 0;
}