/****************************************************************************** * * Copyright(c) 2003 - 2009 Intel Corporation. All rights reserved. * * Portions of this file are derived from the ipw3945 project, as well * as portions of the ieee80211 subsystem header files. * * 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. * * Contact Information: * Intel Linux Wireless * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 * *****************************************************************************/ #include #include #include #include "iwl-eeprom.h" #include "iwl-dev.h" #include "iwl-core.h" #include "iwl-sta.h" #include "iwl-io.h" #include "iwl-calib.h" #include "iwl-helpers.h" /************************** RX-FUNCTIONS ****************************/ /* * Rx theory of operation * * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs), * each of which point to Receive Buffers to be filled by the NIC. These get * used not only for Rx frames, but for any command response or notification * from the NIC. The driver and NIC manage the Rx buffers by means * of indexes into the circular buffer. * * Rx Queue Indexes * The host/firmware share two index registers for managing the Rx buffers. * * The READ index maps to the first position that the firmware may be writing * to -- the driver can read up to (but not including) this position and get * good data. * The READ index is managed by the firmware once the card is enabled. * * The WRITE index maps to the last position the driver has read from -- the * position preceding WRITE is the last slot the firmware can place a packet. * * The queue is empty (no good data) if WRITE = READ - 1, and is full if * WRITE = READ. * * During initialization, the host sets up the READ queue position to the first * INDEX position, and WRITE to the last (READ - 1 wrapped) * * When the firmware places a packet in a buffer, it will advance the READ index * and fire the RX interrupt. The driver can then query the READ index and * process as many packets as possible, moving the WRITE index forward as it * resets the Rx queue buffers with new memory. * * The management in the driver is as follows: * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free. When * iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled * to replenish the iwl->rxq->rx_free. * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the * iwl->rxq is replenished and the READ INDEX is updated (updating the * 'processed' and 'read' driver indexes as well) * + A received packet is processed and handed to the kernel network stack, * detached from the iwl->rxq. The driver 'processed' index is updated. * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free * list. If there are no allocated buffers in iwl->rxq->rx_free, the READ * INDEX is not incremented and iwl->status(RX_STALLED) is set. If there * were enough free buffers and RX_STALLED is set it is cleared. * * * Driver sequence: * * iwl_rx_queue_alloc() Allocates rx_free * iwl_rx_replenish() Replenishes rx_free list from rx_used, and calls * iwl_rx_queue_restock * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx * queue, updates firmware pointers, and updates * the WRITE index. If insufficient rx_free buffers * are available, schedules iwl_rx_replenish * * -- enable interrupts -- * ISR - iwl_rx() Detach iwl_rx_mem_buffers from pool up to the * READ INDEX, detaching the SKB from the pool. * Moves the packet buffer from queue to rx_used. * Calls iwl_rx_queue_restock to refill any empty * slots. * ... * */ /** * iwl_rx_queue_space - Return number of free slots available in queue. */ int iwl_rx_queue_space(const struct iwl_rx_queue *q) { int s = q->read - q->write; if (s <= 0) s += RX_QUEUE_SIZE; /* keep some buffer to not confuse full and empty queue */ s -= 2; if (s < 0) s = 0; return s; } EXPORT_SYMBOL(iwl_rx_queue_space); /** * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue */ int iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q) { unsigned long flags; u32 rx_wrt_ptr_reg = priv->hw_params.rx_wrt_ptr_reg; u32 reg; int ret = 0; spin_lock_irqsave(&q->lock, flags); if (q->need_update == 0) goto exit_unlock; /* If power-saving is in use, make sure device is awake */ if (test_bit(STATUS_POWER_PMI, &priv->status)) { reg = iwl_read32(priv, CSR_UCODE_DRV_GP1); if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) { IWL_DEBUG_INFO(priv, "Rx queue requesting wakeup, GP1 = 0x%x\n", reg); iwl_set_bit(priv, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ); goto exit_unlock; } q->write_actual = (q->write & ~0x7); iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual); /* Else device is assumed to be awake */ } else { /* Device expects a multiple of 8 */ q->write_actual = (q->write & ~0x7); iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual); } q->need_update = 0; exit_unlock: spin_unlock_irqrestore(&q->lock, flags); return ret; } EXPORT_SYMBOL(iwl_rx_queue_update_write_ptr); /** * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr */ static inline __le32 iwl_dma_addr2rbd_ptr(struct iwl_priv *priv, dma_addr_t dma_addr) { return cpu_to_le32((u32)(dma_addr >> 8)); } /** * iwl_rx_queue_restock - refill RX queue from pre-allocated pool * * If there are slots in the RX queue that need to be restocked, * and we have free pre-allocated buffers, fill the ranks as much * as we can, pulling from rx_free. * * This moves the 'write' index forward to catch up with 'processed', and * also updates the memory address in the firmware to reference the new * target buffer. */ int iwl_rx_queue_restock(struct iwl_priv *priv) { struct iwl_rx_queue *rxq = &priv->rxq; struct list_head *element; struct iwl_rx_mem_buffer *rxb; unsigned long flags; int write; int ret = 0; spin_lock_irqsave(&rxq->lock, flags); write = rxq->write & ~0x7; while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) { /* Get next free Rx buffer, remove from free list */ element = rxq->rx_free.next; rxb = list_entry(element, struct iwl_rx_mem_buffer, list); list_del(element); /* Point to Rx buffer via next RBD in circular buffer */ rxq->bd[rxq->write] = iwl_dma_addr2rbd_ptr(priv, rxb->page_dma); rxq->queue[rxq->write] = rxb; rxq->write = (rxq->write + 1) & RX_QUEUE_MASK; rxq->free_count--; } spin_unlock_irqrestore(&rxq->lock, flags); /* If the pre-allocated buffer pool is dropping low, schedule to * refill it */ if (rxq->free_count <= RX_LOW_WATERMARK) queue_work(priv->workqueue, &priv->rx_replenish); /* If we've added more space for the firmware to place data, tell it. * Increment device's write pointer in multiples of 8. */ if (rxq->write_actual != (rxq->write & ~0x7)) { spin_lock_irqsave(&rxq->lock, flags); rxq->need_update = 1; spin_unlock_irqrestore(&rxq->lock, flags); ret = iwl_rx_queue_update_write_ptr(priv, rxq); } return ret; } EXPORT_SYMBOL(iwl_rx_queue_restock); /** * iwl_rx_replenish - Move all used packet from rx_used to rx_free * * When moving to rx_free an SKB is allocated for the slot. * * Also restock the Rx queue via iwl_rx_queue_restock. * This is called as a scheduled work item (except for during initialization) */ void iwl_rx_allocate(struct iwl_priv *priv, gfp_t priority) { struct iwl_rx_queue *rxq = &priv->rxq; struct list_head *element; struct iwl_rx_mem_buffer *rxb; struct page *page; unsigned long flags; gfp_t gfp_mask = priority; while (1) { spin_lock_irqsave(&rxq->lock, flags); if (list_empty(&rxq->rx_used)) { spin_unlock_irqrestore(&rxq->lock, flags); return; } spin_unlock_irqrestore(&rxq->lock, flags); if (rxq->free_count > RX_LOW_WATERMARK) gfp_mask |= __GFP_NOWARN; if (priv->hw_params.rx_page_order > 0) gfp_mask |= __GFP_COMP; /* Alloc a new receive buffer */ page = alloc_pages(gfp_mask, priv->hw_params.rx_page_order); if (!page) { if (net_ratelimit()) IWL_DEBUG_INFO(priv, "alloc_pages failed, " "order: %d\n", priv->hw_params.rx_page_order); if ((rxq->free_count <= RX_LOW_WATERMARK) && net_ratelimit()) IWL_CRIT(priv, "Failed to alloc_pages with %s. Only %u free buffers remaining.\n", priority == GFP_ATOMIC ? "GFP_ATOMIC" : "GFP_KERNEL", rxq->free_count); /* We don't reschedule replenish work here -- we will * call the restock method and if it still needs * more buffers it will schedule replenish */ return; } spin_lock_irqsave(&rxq->lock, flags); if (list_empty(&rxq->rx_used)) { spin_unlock_irqrestore(&rxq->lock, flags); __free_pages(page, priv->hw_params.rx_page_order); return; } element = rxq->rx_used.next; rxb = list_entry(element, struct iwl_rx_mem_buffer, list); list_del(element); spin_unlock_irqrestore(&rxq->lock, flags); rxb->page = page; /* Get physical address of the RB */ rxb->page_dma = pci_map_page(priv->pci_dev, page, 0, PAGE_SIZE << priv->hw_params.rx_page_order, PCI_DMA_FROMDEVICE); /* dma address must be no more than 36 bits */ BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36)); /* and also 256 byte aligned! */ BUG_ON(rxb->page_dma & DMA_BIT_MASK(8)); spin_lock_irqsave(&rxq->lock, flags); list_add_tail(&rxb->list, &rxq->rx_free); rxq->free_count++; priv->alloc_rxb_page++; spin_unlock_irqrestore(&rxq->lock, flags); } } void iwl_rx_replenish(struct iwl_priv *priv) { unsigned long flags; iwl_rx_allocate(priv, GFP_KERNEL); spin_lock_irqsave(&priv->lock, flags); iwl_rx_queue_restock(priv); spin_unlock_irqrestore(&priv->lock, flags); } EXPORT_SYMBOL(iwl_rx_replenish); void iwl_rx_replenish_now(struct iwl_priv *priv) { iwl_rx_allocate(priv, GFP_ATOMIC); iwl_rx_queue_restock(priv); } EXPORT_SYMBOL(iwl_rx_replenish_now); /* Assumes that the skb field of the buffers in 'pool' is kept accurate. * If an SKB has been detached, the POOL needs to have its SKB set to NULL * This free routine walks the list of POOL entries and if SKB is set to * non NULL it is unmapped and freed */ void iwl_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq) { int i; for (i = 0; i < RX_QUEUE_SIZE + RX_FREE_BUFFERS; i++) { if (rxq->pool[i].page != NULL) { pci_unmap_page(priv->pci_dev, rxq->pool[i].page_dma, PAGE_SIZE << priv->hw_params.rx_page_order, PCI_DMA_FROMDEVICE); __free_pages(rxq->pool[i].page, priv->hw_params.rx_page_order); rxq->pool[i].page = NULL; priv->alloc_rxb_page--; } } pci_free_consistent(priv->pci_dev, 4 * RX_QUEUE_SIZE, rxq->bd, rxq->dma_addr); pci_free_consistent(priv->pci_dev, sizeof(struct iwl_rb_status), rxq->rb_stts, rxq->rb_stts_dma); rxq->bd = NULL; rxq->rb_stts = NULL; } EXPORT_SYMBOL(iwl_rx_queue_free); int iwl_rx_queue_alloc(struct iwl_priv *priv) { struct iwl_rx_queue *rxq = &priv->rxq; struct pci_dev *dev = priv->pci_dev; int i; spin_lock_init(&rxq->lock); INIT_LIST_HEAD(&rxq->rx_free); INIT_LIST_HEAD(&rxq->rx_used); /* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */ rxq->bd = pci_alloc_consistent(dev, 4 * RX_QUEUE_SIZE, &rxq->dma_addr); if (!rxq->bd) goto err_bd; rxq->rb_stts = pci_alloc_consistent(dev, sizeof(struct iwl_rb_status), &rxq->rb_stts_dma); if (!rxq->rb_stts) goto err_rb; /* Fill the rx_used queue with _all_ of the Rx buffers */ for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) list_add_tail(&rxq->pool[i].list, &rxq->rx_used); /* Set us so that we have processed and used all buffers, but have * not restocked the Rx queue with fresh buffers */ rxq->read = rxq->write = 0; rxq->write_actual = 0; rxq->free_count = 0; rxq->need_update = 0; return 0; err_rb: pci_free_consistent(priv->pci_dev, 4 * RX_QUEUE_SIZE, rxq->bd, rxq->dma_addr); err_bd: return -ENOMEM; } EXPORT_SYMBOL(iwl_rx_queue_alloc); void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq) { unsigned long flags; int i; spin_lock_irqsave(&rxq->lock, flags); INIT_LIST_HEAD(&rxq->rx_free); INIT_LIST_HEAD(&rxq->rx_used); /* Fill the rx_used queue with _all_ of the Rx buffers */ for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) { /* In the reset function, these buffers may have been allocated * to an SKB, so we need to unmap and free potential storage */ if (rxq->pool[i].page != NULL) { pci_unmap_page(priv->pci_dev, rxq->pool[i].page_dma, PAGE_SIZE << priv->hw_params.rx_page_order, PCI_DMA_FROMDEVICE); priv->alloc_rxb_page--; __free_pages(rxq->pool[i].page, priv->hw_params.rx_page_order); rxq->pool[i].page = NULL; } list_add_tail(&rxq->pool[i].list, &rxq->rx_used); } /* Set us so that we have processed and used all buffers, but have * not restocked the Rx queue with fresh buffers */ rxq->read = rxq->write = 0; rxq->write_actual = 0; rxq->free_count = 0; spin_unlock_irqrestore(&rxq->lock, flags); } int iwl_rx_init(struct iwl_priv *priv, struct iwl_rx_queue *rxq) { u32 rb_size; const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */ u32 rb_timeout = 0; /* FIXME: RX_RB_TIMEOUT for all devices? */ if (!priv->cfg->use_isr_legacy) rb_timeout = RX_RB_TIMEOUT; if (priv->cfg->mod_params->amsdu_size_8K) rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K; else rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K; /* Stop Rx DMA */ iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0); /* Reset driver's Rx queue write index */ iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0); /* Tell device where to find RBD circular buffer in DRAM */ iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_BASE_REG, (u32)(rxq->dma_addr >> 8)); /* Tell device where in DRAM to update its Rx status */ iwl_write_direct32(priv, FH_RSCSR_CHNL0_STTS_WPTR_REG, rxq->rb_stts_dma >> 4); /* Enable Rx DMA * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in * the credit mechanism in 5000 HW RX FIFO * Direct rx interrupts to hosts * Rx buffer size 4 or 8k * RB timeout 0x10 * 256 RBDs */ iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL | FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY | FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL | FH_RCSR_CHNL0_RX_CONFIG_SINGLE_FRAME_MSK | rb_size| (rb_timeout << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS)| (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS)); /* Set interrupt coalescing timer to 64 x 32 = 2048 usecs */ iwl_write8(priv, CSR_INT_COALESCING, 0x40); return 0; } int iwl_rxq_stop(struct iwl_priv *priv) { /* stop Rx DMA */ iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0); iwl_poll_direct_bit(priv, FH_MEM_RSSR_RX_STATUS_REG, FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE, 1000); return 0; } EXPORT_SYMBOL(iwl_rxq_stop); void iwl_rx_missed_beacon_notif(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) { struct iwl_rx_packet *pkt = rxb_addr(rxb); struct iwl_missed_beacon_notif *missed_beacon; missed_beacon = &pkt->u.missed_beacon; if (le32_to_cpu(missed_beacon->consequtive_missed_beacons) > 5) { IWL_DEBUG_CALIB(priv, "missed bcn cnsq %d totl %d rcd %d expctd %d\n", le32_to_cpu(missed_beacon->consequtive_missed_beacons), le32_to_cpu(missed_beacon->total_missed_becons), le32_to_cpu(missed_beacon->num_recvd_beacons), le32_to_cpu(missed_beacon->num_expected_beacons)); if (!test_bit(STATUS_SCANNING, &priv->status)) iwl_init_sensitivity(priv); } } EXPORT_SYMBOL(iwl_rx_missed_beacon_notif); /* Calculate noise level, based on measurements during network silence just * before arriving beacon. This measurement can be done only if we know * exactly when to expect beacons, therefore only when we're associated. */ static void iwl_rx_calc_noise(struct iwl_priv *priv) { struct statistics_rx_non_phy *rx_info = &(priv->statistics.rx.general); int num_active_rx = 0; int total_silence = 0; int bcn_silence_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER; int bcn_silence_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER; int bcn_silence_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER; if (bcn_silence_a) { total_silence += bcn_silence_a; num_active_rx++; } if (bcn_silence_b) { total_silence += bcn_silence_b; num_active_rx++; } if (bcn_silence_c) { total_silence += bcn_silence_c; num_active_rx++; } /* Average among active antennas */ if (num_active_rx) priv->last_rx_noise = (total_silence / num_active_rx) - 107; else priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE; IWL_DEBUG_CALIB(priv, "inband silence a %u, b %u, c %u, dBm %d\n", bcn_silence_a, bcn_silence_b, bcn_silence_c, priv->last_rx_noise); } #ifdef CONFIG_IWLWIFI_DEBUG /* * based on the assumption of all statistics counter are in DWORD * FIXME: This function is for debugging, do not deal with * the case of counters roll-over. */ static void iwl_accumulative_statistics(struct iwl_priv *priv, __le32 *stats) { int i; __le32 *prev_stats; u32 *accum_stats; prev_stats = (__le32 *)&priv->statistics; accum_stats = (u32 *)&priv->accum_statistics; for (i = sizeof(__le32); i < sizeof(struct iwl_notif_statistics); i += sizeof(__le32), stats++, prev_stats++, accum_stats++) if (le32_to_cpu(*stats) > le32_to_cpu(*prev_stats)) *accum_stats += (le32_to_cpu(*stats) - le32_to_cpu(*prev_stats)); /* reset accumulative statistics for "no-counter" type statistics */ priv->accum_statistics.general.temperature = priv->statistics.general.temperature; priv->accum_statistics.general.temperature_m = priv->statistics.general.temperature_m; priv->accum_statistics.general.ttl_timestamp = priv->statistics.general.ttl_timestamp; priv->accum_statistics.tx.tx_power.ant_a = priv->statistics.tx.tx_power.ant_a; priv->accum_statistics.tx.tx_power.ant_b = priv->statistics.tx.tx_power.ant_b; priv->accum_statistics.tx.tx_power.ant_c = priv->statistics.tx.tx_power.ant_c; } #endif #define REG_RECALIB_PERIOD (60) void iwl_rx_statistics(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) { int change; struct iwl_rx_packet *pkt = rxb_addr(rxb); IWL_DEBUG_RX(priv, "Statistics notification received (%d vs %d).\n", (int)sizeof(priv->statistics), le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_FRAME_SIZE_MSK); change = ((priv->statistics.general.temperature != pkt->u.stats.general.temperature) || ((priv->statistics.flag & STATISTICS_REPLY_FLG_HT40_MODE_MSK) != (pkt->u.stats.flag & STATISTICS_REPLY_FLG_HT40_MODE_MSK))); #ifdef CONFIG_IWLWIFI_DEBUG iwl_accumulative_statistics(priv, (__le32 *)&pkt->u.stats); #endif memcpy(&priv->statistics, &pkt->u.stats, sizeof(priv->statistics)); set_bit(STATUS_STATISTICS, &priv->status); /* Reschedule the statistics timer to occur in * REG_RECALIB_PERIOD seconds to ensure we get a * thermal update even if the uCode doesn't give * us one */ mod_timer(&priv->statistics_periodic, jiffies + msecs_to_jiffies(REG_RECALIB_PERIOD * 1000)); if (unlikely(!test_bit(STATUS_SCANNING, &priv->status)) && (pkt->hdr.cmd == STATISTICS_NOTIFICATION)) { iwl_rx_calc_noise(priv); queue_work(priv->workqueue, &priv->run_time_calib_work); } if (priv->cfg->ops->lib->temp_ops.temperature && change) priv->cfg->ops->lib->temp_ops.temperature(priv); } EXPORT_SYMBOL(iwl_rx_statistics); void iwl_reply_statistics(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) { struct iwl_rx_packet *pkt = rxb_addr(rxb); if (le32_to_cpu(pkt->u.stats.flag) & UCODE_STATISTICS_CLEAR_MSK) { memset(&priv->statistics, 0, sizeof(struct iwl_notif_statistics)); #ifdef CONFIG_IWLWIFI_DEBUG memset(&priv->accum_statistics, 0, sizeof(struct iwl_notif_statistics)); #endif IWL_DEBUG_RX(priv, "Statistics have been cleared\n"); } iwl_rx_statistics(priv, rxb); } EXPORT_SYMBOL(iwl_reply_statistics); #define PERFECT_RSSI (-20) /* dBm */ #define WORST_RSSI (-95) /* dBm */ #define RSSI_RANGE (PERFECT_RSSI - WORST_RSSI) /* Calculate an indication of rx signal quality (a percentage, not dBm!). * See http://www.ces.clemson.edu/linux/signal_quality.shtml for info * about formulas used below. */ static int iwl_calc_sig_qual(int rssi_dbm, int noise_dbm) { int sig_qual; int degradation = PERFECT_RSSI - rssi_dbm; /* If we get a noise measurement, use signal-to-noise ratio (SNR) * as indicator; formula is (signal dbm - noise dbm). * SNR at or above 40 is a great signal (100%). * Below that, scale to fit SNR of 0 - 40 dB within 0 - 100% indicator. * Weakest usable signal is usually 10 - 15 dB SNR. */ if (noise_dbm) { if (rssi_dbm - noise_dbm >= 40) return 100; else if (rssi_dbm < noise_dbm) return 0; sig_qual = ((rssi_dbm - noise_dbm) * 5) / 2; /* Else use just the signal level. * This formula is a least squares fit of data points collected and * compared with a reference system that had a percentage (%) display * for signal quality. */ } else sig_qual = (100 * (RSSI_RANGE * RSSI_RANGE) - degradation * (15 * RSSI_RANGE + 62 * degradation)) / (RSSI_RANGE * RSSI_RANGE); if (sig_qual > 100) sig_qual = 100; else if (sig_qual < 1) sig_qual = 0; return sig_qual; } /* Calc max signal level (dBm) among 3 possible receivers */ static inline int iwl_calc_rssi(struct iwl_priv *priv, struct iwl_rx_phy_res *rx_resp) { return priv->cfg->ops->utils->calc_rssi(priv, rx_resp); } #ifdef CONFIG_IWLWIFI_DEBUG /** * iwl_dbg_report_frame - dump frame to syslog during debug sessions * * You may hack this function to show different aspects of received frames, * including selective frame dumps. * group100 parameter selects whether to show 1 out of 100 good data frames. * All beacon and probe response frames are printed. */ static void iwl_dbg_report_frame(struct iwl_priv *priv, struct iwl_rx_phy_res *phy_res, u16 length, struct ieee80211_hdr *header, int group100) { u32 to_us; u32 print_summary = 0; u32 print_dump = 0; /* set to 1 to dump all frames' contents */ u32 hundred = 0; u32 dataframe = 0; __le16 fc; u16 seq_ctl; u16 channel; u16 phy_flags; u32 rate_n_flags; u32 tsf_low; int rssi; if (likely(!(iwl_get_debug_level(priv) & IWL_DL_RX))) return; /* MAC header */ fc = header->frame_control; seq_ctl = le16_to_cpu(header->seq_ctrl); /* metadata */ channel = le16_to_cpu(phy_res->channel); phy_flags = le16_to_cpu(phy_res->phy_flags); rate_n_flags = le32_to_cpu(phy_res->rate_n_flags); /* signal statistics */ rssi = iwl_calc_rssi(priv, phy_res); tsf_low = le64_to_cpu(phy_res->timestamp) & 0x0ffffffff; to_us = !compare_ether_addr(header->addr1, priv->mac_addr); /* if data frame is to us and all is good, * (optionally) print summary for only 1 out of every 100 */ if (to_us && (fc & ~cpu_to_le16(IEEE80211_FCTL_PROTECTED)) == cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FTYPE_DATA)) { dataframe = 1; if (!group100) print_summary = 1; /* print each frame */ else if (priv->framecnt_to_us < 100) { priv->framecnt_to_us++; print_summary = 0; } else { priv->framecnt_to_us = 0; print_summary = 1; hundred = 1; } } else { /* print summary for all other frames */ print_summary = 1; } if (print_summary) { char *title; int rate_idx; u32 bitrate; if (hundred) title = "100Frames"; else if (ieee80211_has_retry(fc)) title = "Retry"; else if (ieee80211_is_assoc_resp(fc)) title = "AscRsp"; else if (ieee80211_is_reassoc_resp(fc)) title = "RasRsp"; else if (ieee80211_is_probe_resp(fc)) { title = "PrbRsp"; print_dump = 1; /* dump frame contents */ } else if (ieee80211_is_beacon(fc)) { title = "Beacon"; print_dump = 1; /* dump frame contents */ } else if (ieee80211_is_atim(fc)) title = "ATIM"; else if (ieee80211_is_auth(fc)) title = "Auth"; else if (ieee80211_is_deauth(fc)) title = "DeAuth"; else if (ieee80211_is_disassoc(fc)) title = "DisAssoc"; else title = "Frame"; rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags); if (unlikely((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT))) { bitrate = 0; WARN_ON_ONCE(1); } else { bitrate = iwl_rates[rate_idx].ieee / 2; } /* print frame summary. * MAC addresses show just the last byte (for brevity), * but you can hack it to show more, if you'd like to. */ if (dataframe) IWL_DEBUG_RX(priv, "%s: mhd=0x%04x, dst=0x%02x, " "len=%u, rssi=%d, chnl=%d, rate=%u, \n", title, le16_to_cpu(fc), header->addr1[5], length, rssi, channel, bitrate); else { /* src/dst addresses assume managed mode */ IWL_DEBUG_RX(priv, "%s: 0x%04x, dst=0x%02x, src=0x%02x, " "len=%u, rssi=%d, tim=%lu usec, " "phy=0x%02x, chnl=%d\n", title, le16_to_cpu(fc), header->addr1[5], header->addr3[5], length, rssi, tsf_low - priv->scan_start_tsf, phy_flags, channel); } } if (print_dump) iwl_print_hex_dump(priv, IWL_DL_RX, header, length); } #endif /* * returns non-zero if packet should be dropped */ int iwl_set_decrypted_flag(struct iwl_priv *priv, struct ieee80211_hdr *hdr, u32 decrypt_res, struct ieee80211_rx_status *stats) { u16 fc = le16_to_cpu(hdr->frame_control); if (priv->active_rxon.filter_flags & RXON_FILTER_DIS_DECRYPT_MSK) return 0; if (!(fc & IEEE80211_FCTL_PROTECTED)) return 0; IWL_DEBUG_RX(priv, "decrypt_res:0x%x\n", decrypt_res); switch (decrypt_res & RX_RES_STATUS_SEC_TYPE_MSK) { case RX_RES_STATUS_SEC_TYPE_TKIP: /* The uCode has got a bad phase 1 Key, pushes the packet. * Decryption will be done in SW. */ if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) == RX_RES_STATUS_BAD_KEY_TTAK) break; case RX_RES_STATUS_SEC_TYPE_WEP: if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) == RX_RES_STATUS_BAD_ICV_MIC) { /* bad ICV, the packet is destroyed since the * decryption is inplace, drop it */ IWL_DEBUG_RX(priv, "Packet destroyed\n"); return -1; } case RX_RES_STATUS_SEC_TYPE_CCMP: if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) == RX_RES_STATUS_DECRYPT_OK) { IWL_DEBUG_RX(priv, "hw decrypt successfully!!!\n"); stats->flag |= RX_FLAG_DECRYPTED; } break; default: break; } return 0; } EXPORT_SYMBOL(iwl_set_decrypted_flag); static u32 iwl_translate_rx_status(struct iwl_priv *priv, u32 decrypt_in) { u32 decrypt_out = 0; if ((decrypt_in & RX_RES_STATUS_STATION_FOUND) == RX_RES_STATUS_STATION_FOUND) decrypt_out |= (RX_RES_STATUS_STATION_FOUND | RX_RES_STATUS_NO_STATION_INFO_MISMATCH); decrypt_out |= (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK); /* packet was not encrypted */ if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) == RX_RES_STATUS_SEC_TYPE_NONE) return decrypt_out; /* packet was encrypted with unknown alg */ if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) == RX_RES_STATUS_SEC_TYPE_ERR) return decrypt_out; /* decryption was not done in HW */ if ((decrypt_in & RX_MPDU_RES_STATUS_DEC_DONE_MSK) != RX_MPDU_RES_STATUS_DEC_DONE_MSK) return decrypt_out; switch (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) { case RX_RES_STATUS_SEC_TYPE_CCMP: /* alg is CCM: check MIC only */ if (!(decrypt_in & RX_MPDU_RES_STATUS_MIC_OK)) /* Bad MIC */ decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC; else decrypt_out |= RX_RES_STATUS_DECRYPT_OK; break; case RX_RES_STATUS_SEC_TYPE_TKIP: if (!(decrypt_in & RX_MPDU_RES_STATUS_TTAK_OK)) { /* Bad TTAK */ decrypt_out |= RX_RES_STATUS_BAD_KEY_TTAK; break; } /* fall through if TTAK OK */ default: if (!(decrypt_in & RX_MPDU_RES_STATUS_ICV_OK)) decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC; else decrypt_out |= RX_RES_STATUS_DECRYPT_OK; break; }; IWL_DEBUG_RX(priv, "decrypt_in:0x%x decrypt_out = 0x%x\n", decrypt_in, decrypt_out); return decrypt_out; } static void iwl_pass_packet_to_mac80211(struct iwl_priv *priv, struct ieee80211_hdr *hdr, u16 len, u32 ampdu_status, struct iwl_rx_mem_buffer *rxb, struct ieee80211_rx_status *stats) { struct sk_buff *skb; int ret = 0; __le16 fc = hdr->frame_control; /* We only process data packets if the interface is open */ if (unlikely(!priv->is_open)) { IWL_DEBUG_DROP_LIMIT(priv, "Dropping packet while interface is not open.\n"); return; } /* In case of HW accelerated crypto and bad decryption, drop */ if (!priv->cfg->mod_params->sw_crypto && iwl_set_decrypted_flag(priv, hdr, ampdu_status, stats)) return; skb = alloc_skb(IWL_LINK_HDR_MAX * 2, GFP_ATOMIC); if (!skb) { IWL_ERR(priv, "alloc_skb failed\n"); return; } skb_reserve(skb, IWL_LINK_HDR_MAX); skb_add_rx_frag(skb, 0, rxb->page, (void *)hdr - rxb_addr(rxb), len); /* mac80211 currently doesn't support paged SKB. Convert it to * linear SKB for management frame and data frame requires * software decryption or software defragementation. */ if (ieee80211_is_mgmt(fc) || ieee80211_has_protected(fc) || ieee80211_has_morefrags(fc) || le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG) ret = skb_linearize(skb); else ret = __pskb_pull_tail(skb, min_t(u16, IWL_LINK_HDR_MAX, len)) ? 0 : -ENOMEM; if (ret) { kfree_skb(skb); goto out; } /* * XXX: We cannot touch the page and its virtual memory (hdr) after * here. It might have already been freed by the above skb change. */ iwl_update_stats(priv, false, fc, len); memcpy(IEEE80211_SKB_RXCB(skb), stats, sizeof(*stats)); ieee80211_rx(priv->hw, skb); out: priv->alloc_rxb_page--; rxb->page = NULL; } /* This is necessary only for a number of statistics, see the caller. */ static int iwl_is_network_packet(struct iwl_priv *priv, struct ieee80211_hdr *header) { /* Filter incoming packets to determine if they are targeted toward * this network, discarding packets coming from ourselves */ switch (priv->iw_mode) { case NL80211_IFTYPE_ADHOC: /* Header: Dest. | Source | BSSID */ /* packets to our IBSS update information */ return !compare_ether_addr(header->addr3, priv->bssid); case NL80211_IFTYPE_STATION: /* Header: Dest. | AP{BSSID} | Source */ /* packets to our IBSS update information */ return !compare_ether_addr(header->addr2, priv->bssid); default: return 1; } } /* Called for REPLY_RX (legacy ABG frames), or * REPLY_RX_MPDU_CMD (HT high-throughput N frames). */ void iwl_rx_reply_rx(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) { struct ieee80211_hdr *header; struct ieee80211_rx_status rx_status; struct iwl_rx_packet *pkt = rxb_addr(rxb); struct iwl_rx_phy_res *phy_res; __le32 rx_pkt_status; struct iwl4965_rx_mpdu_res_start *amsdu; u32 len; u32 ampdu_status; u32 rate_n_flags; /** * REPLY_RX and REPLY_RX_MPDU_CMD are handled differently. * REPLY_RX: physical layer info is in this buffer * REPLY_RX_MPDU_CMD: physical layer info was sent in separate * command and cached in priv->last_phy_res * * Here we set up local variables depending on which command is * received. */ if (pkt->hdr.cmd == REPLY_RX) { phy_res = (struct iwl_rx_phy_res *)pkt->u.raw; header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*phy_res) + phy_res->cfg_phy_cnt); len = le16_to_cpu(phy_res->byte_count); rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*phy_res) + phy_res->cfg_phy_cnt + len); ampdu_status = le32_to_cpu(rx_pkt_status); } else { if (!priv->last_phy_res[0]) { IWL_ERR(priv, "MPDU frame without cached PHY data\n"); return; } phy_res = (struct iwl_rx_phy_res *)&priv->last_phy_res[1]; amsdu = (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw; header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*amsdu)); len = le16_to_cpu(amsdu->byte_count); rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*amsdu) + len); ampdu_status = iwl_translate_rx_status(priv, le32_to_cpu(rx_pkt_status)); } if ((unlikely(phy_res->cfg_phy_cnt > 20))) { IWL_DEBUG_DROP(priv, "dsp size out of range [0,20]: %d/n", phy_res->cfg_phy_cnt); return; } if (!(rx_pkt_status & RX_RES_STATUS_NO_CRC32_ERROR) || !(rx_pkt_status & RX_RES_STATUS_NO_RXE_OVERFLOW)) { IWL_DEBUG_RX(priv, "Bad CRC or FIFO: 0x%08X.\n", le32_to_cpu(rx_pkt_status)); return; } /* This will be used in several places later */ rate_n_flags = le32_to_cpu(phy_res->rate_n_flags); /* rx_status carries information about the packet to mac80211 */ rx_status.mactime = le64_to_cpu(phy_res->timestamp); rx_status.freq = ieee80211_channel_to_frequency(le16_to_cpu(phy_res->channel)); rx_status.band = (phy_res->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ? IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ; rx_status.rate_idx = iwl_hwrate_to_mac80211_idx(rate_n_flags, rx_status.band); rx_status.flag = 0; /* TSF isn't reliable. In order to allow smooth user experience, * this W/A doesn't propagate it to the mac80211 */ /*rx_status.flag |= RX_FLAG_TSFT;*/ priv->ucode_beacon_time = le32_to_cpu(phy_res->beacon_time_stamp); /* Find max signal strength (dBm) among 3 antenna/receiver chains */ rx_status.signal = iwl_calc_rssi(priv, phy_res); /* Meaningful noise values are available only from beacon statistics, * which are gathered only when associated, and indicate noise * only for the associated network channel ... * Ignore these noise values while scanning (other channels) */ if (iwl_is_associated(priv) && !test_bit(STATUS_SCANNING, &priv->status)) { rx_status.noise = priv->last_rx_noise; rx_status.qual = iwl_calc_sig_qual(rx_status.signal, rx_status.noise); } else { rx_status.noise = IWL_NOISE_MEAS_NOT_AVAILABLE; rx_status.qual = iwl_calc_sig_qual(rx_status.signal, 0); } /* Reset beacon noise level if not associated. */ if (!iwl_is_associated(priv)) priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE; #ifdef CONFIG_IWLWIFI_DEBUG /* Set "1" to report good data frames in groups of 100 */ if (unlikely(iwl_get_debug_level(priv) & IWL_DL_RX)) iwl_dbg_report_frame(priv, phy_res, len, header, 1); #endif iwl_dbg_log_rx_data_frame(priv, len, header); IWL_DEBUG_STATS_LIMIT(priv, "Rssi %d, noise %d, qual %d, TSF %llu\n", rx_status.signal, rx_status.noise, rx_status.qual, (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_res->phy_flags) & RX_RES_PHY_FLAGS_ANTENNA_MSK) >> RX_RES_PHY_FLAGS_ANTENNA_POS; /* set the preamble flag if appropriate */ if (phy_res->phy_flags & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK) rx_status.flag |= RX_FLAG_SHORTPRE; /* Set up the HT phy flags */ if (rate_n_flags & RATE_MCS_HT_MSK) rx_status.flag |= RX_FLAG_HT; if (rate_n_flags & RATE_MCS_HT40_MSK) rx_status.flag |= RX_FLAG_40MHZ; if (rate_n_flags & RATE_MCS_SGI_MSK) rx_status.flag |= RX_FLAG_SHORT_GI; if (iwl_is_network_packet(priv, header)) { priv->last_rx_rssi = rx_status.signal; priv->last_beacon_time = priv->ucode_beacon_time; priv->last_tsf = le64_to_cpu(phy_res->timestamp); } iwl_pass_packet_to_mac80211(priv, header, len, ampdu_status, rxb, &rx_status); } EXPORT_SYMBOL(iwl_rx_reply_rx); /* Cache phy data (Rx signal strength, etc) for HT frame (REPLY_RX_PHY_CMD). * This will be used later in iwl_rx_reply_rx() for REPLY_RX_MPDU_CMD. */ void iwl_rx_reply_rx_phy(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) { struct iwl_rx_packet *pkt = rxb_addr(rxb); priv->last_phy_res[0] = 1; memcpy(&priv->last_phy_res[1], &(pkt->u.raw[0]), sizeof(struct iwl_rx_phy_res)); } EXPORT_SYMBOL(iwl_rx_reply_rx_phy);