iwlwifi: add the MVM driver

Newer firmware revisions have a completely new
firmware API. This is the new driver for this
new API.

I've listed the people who directly contributed
code, but many others from various teams have
contributed in other ways.

Cc: Alexander Bondar <alexander.bondar@intel.com>
Cc: Amit Beka <amit.beka@intel.com>
Cc: Amnon Paz <amnonx.paz@intel.com>
Cc: Assaf Krauss <assaf.krauss@intel.com>
Cc: David Spinadel <david.spinadel@intel.com>
Cc: Dor Shaish <dor.shaish@intel.com>
Cc: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Cc: Eytan Lifshitz <eytan.lifshitz@intel.com>
Cc: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 355 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/rx.c b/drivers/net/wireless/iwlwifi/mvm/rx.c
new file mode 100644
index 0000000..52da375
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/mvm/rx.c
@@ -0,0 +1,355 @@
+/******************************************************************************
+ *
+ * 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 LICENSE.GPL.
+ *
+ * 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(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)
+{
+	u32 rssi_a, rssi_b, rssi_c, max_rssi, agc_db;
+	u32 val;
+
+	/* Find max rssi among 3 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_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;
+	val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_RSSI_C_IDX]);
+	rssi_c = (val & IWL_OFDM_RSSI_INBAND_C_MSK) >> IWL_OFDM_RSSI_C_POS;
+
+	val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_AGC_IDX]);
+	agc_db = (val & IWL_OFDM_AGC_DB_MSK) >> IWL_OFDM_AGC_DB_POS;
+
+	max_rssi = max_t(u32, rssi_a, rssi_b);
+	max_rssi = max_t(u32, max_rssi, rssi_c);
+
+	IWL_DEBUG_STATS(mvm, "Rssi In A %d B %d C %d Max %d AGC dB %d\n",
+			rssi_a, rssi_b, rssi_c, max_rssi, agc_db);
+
+	/* dBm = max_rssi dB - agc dB - constant.
+	 * Higher AGC (higher radio gain) means lower signal. */
+	return max_rssi - agc_db - IWL_RSSI_OFFSET;
+}
+
+/*
+ * 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.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;
+}