linux/drivers/net/wireless/iwlwifi/iwl-rx.c
Reinette Chatre a562a9dda7 iwlwifi: make debug level more user friendly
* Deprecate the "debug50" module parameter used to obtain
  5000 series and up debugging. Replace it with "debug" module
  parameter to match with original driver and be consistent
  between them. The "debug50" module parameter can still be used,
  except that the module parameter is not writable in keeping
  with its previous state. We currently just mark it as "deprecated"
  and do not have it in the feature-removal-schedule. Some more
  cleanup of module parameters needs to be done and can then be
  entered together.

* Only make "debug" module parameters visible if the driver
  is compiled with CONFIG_IWLWIFI_DEBUG. This will eliminate
  a lot of confusion where users think they have set debug flags
  but yet cannot see any debug output.

* Make module parameters writable. This eliminates the need for the
  "debug_level" sysfs file, which can now also be deprecated and
  added to feature-removal-schedule. This file is in significant
  use though with many iwlwifi documents and text referring users
  to it. We can thus not take its removal lightly and keep it around.

With iwlcore shared between iwlagn and iwl3945 we really do not need
debug module parameters for each but can instead have one debug
module parameter for the iwlcore module. The same issue is here as
with the sysfs file - a lot of iwlwifi documentation and text (like
bug reports) rely on iwlagn and iwl3945 having this module parameter,
so changing this to a module parameter of iwlcore will have significant
impact and we do not do this for that reason.

One consequence of this patch is that if a user is running a system
with both 3945 and later hardware then the setting of the one module
parameter will affect the value of the other. The likelihood of this
seems low - and even if this setup is present it does not seem like an
issue for both modules to run with the same debug level.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-24 15:05:25 -04:00

1126 lines
34 KiB
C

/******************************************************************************
*
* 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 <ilw@linux.intel.com>
* Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
*
*****************************************************************************/
#include <linux/etherdevice.h>
#include <net/mac80211.h>
#include <asm/unaligned.h>
#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_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->aligned_dma_addr);
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;
unsigned long flags;
while (1) {
spin_lock_irqsave(&rxq->lock, flags);
if (list_empty(&rxq->rx_used)) {
spin_unlock_irqrestore(&rxq->lock, flags);
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);
/* Alloc a new receive buffer */
rxb->skb = alloc_skb(priv->hw_params.rx_buf_size + 256,
priority);
if (!rxb->skb) {
IWL_CRIT(priv, "Can not allocate SKB buffers\n");
/* We don't reschedule replenish work here -- we will
* call the restock method and if it still needs
* more buffers it will schedule replenish */
break;
}
/* Get physical address of RB/SKB */
rxb->real_dma_addr = pci_map_single(
priv->pci_dev,
rxb->skb->data,
priv->hw_params.rx_buf_size + 256,
PCI_DMA_FROMDEVICE);
/* dma address must be no more than 36 bits */
BUG_ON(rxb->real_dma_addr & ~DMA_BIT_MASK(36));
/* and also 256 byte aligned! */
rxb->aligned_dma_addr = ALIGN(rxb->real_dma_addr, 256);
skb_reserve(rxb->skb, rxb->aligned_dma_addr - rxb->real_dma_addr);
spin_lock_irqsave(&rxq->lock, flags);
list_add_tail(&rxb->list, &rxq->rx_free);
rxq->free_count++;
priv->alloc_rxb_skb++;
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].skb != NULL) {
pci_unmap_single(priv->pci_dev,
rxq->pool[i].real_dma_addr,
priv->hw_params.rx_buf_size + 256,
PCI_DMA_FROMDEVICE);
dev_kfree_skb(rxq->pool[i].skb);
}
}
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].skb != NULL) {
pci_unmap_single(priv->pci_dev,
rxq->pool[i].real_dma_addr,
priv->hw_params.rx_buf_size + 256,
PCI_DMA_FROMDEVICE);
priv->alloc_rxb_skb--;
dev_kfree_skb(rxq->pool[i].skb);
rxq->pool[i].skb = 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);
}
EXPORT_SYMBOL(iwl_rx_queue_reset);
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));
iwl_write32(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 = (struct iwl_rx_packet *)rxb->skb->data;
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);
}
#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 = (struct iwl_rx_packet *)rxb->skb->data;
IWL_DEBUG_RX(priv, "Statistics notification received (%d vs %d).\n",
(int)sizeof(priv->statistics), pkt->len);
change = ((priv->statistics.general.temperature !=
pkt->u.stats.general.temperature) ||
((priv->statistics.flag &
STATISTICS_REPLY_FLG_FAT_MODE_MSK) !=
(pkt->u.stats.flag & STATISTICS_REPLY_FLG_FAT_MODE_MSK)));
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);
}
iwl_leds_background(priv);
if (priv->cfg->ops->lib->temp_ops.temperature && change)
priv->cfg->ops->lib->temp_ops.temperature(priv);
}
EXPORT_SYMBOL(iwl_rx_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_debug_level & 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(IWL_DL_RX, header, length);
}
#endif
static void iwl_update_rx_stats(struct iwl_priv *priv, u16 fc, u16 len)
{
/* 0 - mgmt, 1 - cnt, 2 - data */
int idx = (fc & IEEE80211_FCTL_FTYPE) >> 2;
priv->rx_stats[idx].cnt++;
priv->rx_stats[idx].bytes += len;
}
/*
* 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,
int include_phy,
struct iwl_rx_mem_buffer *rxb,
struct ieee80211_rx_status *stats)
{
struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
struct iwl_rx_phy_res *rx_start = (include_phy) ?
(struct iwl_rx_phy_res *)&(pkt->u.raw[0]) : NULL;
struct ieee80211_hdr *hdr;
u16 len;
__le32 *rx_end;
unsigned int skblen;
u32 ampdu_status;
u32 ampdu_status_legacy;
if (!include_phy && priv->last_phy_res[0])
rx_start = (struct iwl_rx_phy_res *)&priv->last_phy_res[1];
if (!rx_start) {
IWL_ERR(priv, "MPDU frame without a PHY data\n");
return;
}
if (include_phy) {
hdr = (struct ieee80211_hdr *)((u8 *) &rx_start[1] +
rx_start->cfg_phy_cnt);
len = le16_to_cpu(rx_start->byte_count);
rx_end = (__le32 *)((u8 *) &pkt->u.raw[0] +
sizeof(struct iwl_rx_phy_res) +
rx_start->cfg_phy_cnt + len);
} else {
struct iwl4965_rx_mpdu_res_start *amsdu =
(struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
hdr = (struct ieee80211_hdr *)(pkt->u.raw +
sizeof(struct iwl4965_rx_mpdu_res_start));
len = le16_to_cpu(amsdu->byte_count);
rx_start->byte_count = amsdu->byte_count;
rx_end = (__le32 *) (((u8 *) hdr) + len);
}
ampdu_status = le32_to_cpu(*rx_end);
skblen = ((u8 *) rx_end - (u8 *) &pkt->u.raw[0]) + sizeof(u32);
if (!include_phy) {
/* New status scheme, need to translate */
ampdu_status_legacy = ampdu_status;
ampdu_status = iwl_translate_rx_status(priv, ampdu_status);
}
/* start from MAC */
skb_reserve(rxb->skb, (void *)hdr - (void *)pkt);
skb_put(rxb->skb, len); /* end where data ends */
/* 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;
}
hdr = (struct ieee80211_hdr *)rxb->skb->data;
/* 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;
iwl_update_rx_stats(priv, le16_to_cpu(hdr->frame_control), len);
memcpy(IEEE80211_SKB_RXCB(rxb->skb), stats, sizeof(*stats));
ieee80211_rx_irqsafe(priv->hw, rxb->skb);
priv->alloc_rxb_skb--;
rxb->skb = 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 = (struct iwl_rx_packet *)rxb->skb->data;
/* Use phy data (Rx signal strength, etc.) contained within
* this rx packet for legacy frames,
* or phy data cached from REPLY_RX_PHY_CMD for HT frames. */
int include_phy = (pkt->hdr.cmd == REPLY_RX);
struct iwl_rx_phy_res *rx_start = (include_phy) ?
(struct iwl_rx_phy_res *)&(pkt->u.raw[0]) :
(struct iwl_rx_phy_res *)&priv->last_phy_res[1];
__le32 *rx_end;
unsigned int len = 0;
u16 fc;
u8 network_packet;
rx_status.mactime = le64_to_cpu(rx_start->timestamp);
rx_status.freq =
ieee80211_channel_to_frequency(le16_to_cpu(rx_start->channel));
rx_status.band = (rx_start->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ?
IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
rx_status.rate_idx =
iwl_hwrate_to_plcp_idx(le32_to_cpu(rx_start->rate_n_flags));
if (rx_status.band == IEEE80211_BAND_5GHZ)
rx_status.rate_idx -= IWL_FIRST_OFDM_RATE;
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;*/
if ((unlikely(rx_start->cfg_phy_cnt > 20))) {
IWL_DEBUG_DROP(priv, "dsp size out of range [0,20]: %d/n",
rx_start->cfg_phy_cnt);
return;
}
if (!include_phy) {
if (priv->last_phy_res[0])
rx_start = (struct iwl_rx_phy_res *)
&priv->last_phy_res[1];
else
rx_start = NULL;
}
if (!rx_start) {
IWL_ERR(priv, "MPDU frame without a PHY data\n");
return;
}
if (include_phy) {
header = (struct ieee80211_hdr *)((u8 *) &rx_start[1]
+ rx_start->cfg_phy_cnt);
len = le16_to_cpu(rx_start->byte_count);
rx_end = (__le32 *)(pkt->u.raw + rx_start->cfg_phy_cnt +
sizeof(struct iwl_rx_phy_res) + len);
} else {
struct iwl4965_rx_mpdu_res_start *amsdu =
(struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
header = (void *)(pkt->u.raw +
sizeof(struct iwl4965_rx_mpdu_res_start));
len = le16_to_cpu(amsdu->byte_count);
rx_end = (__le32 *) (pkt->u.raw +
sizeof(struct iwl4965_rx_mpdu_res_start) + len);
}
if (!(*rx_end & RX_RES_STATUS_NO_CRC32_ERROR) ||
!(*rx_end & RX_RES_STATUS_NO_RXE_OVERFLOW)) {
IWL_DEBUG_RX(priv, "Bad CRC or FIFO: 0x%08X.\n",
le32_to_cpu(*rx_end));
return;
}
priv->ucode_beacon_time = le32_to_cpu(rx_start->beacon_time_stamp);
/* Find max signal strength (dBm) among 3 antenna/receiver chains */
rx_status.signal = iwl_calc_rssi(priv, rx_start);
/* 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;
/* Set "1" to report good data frames in groups of 100 */
#ifdef CONFIG_IWLWIFI_DEBUG
if (unlikely(iwl_debug_level & IWL_DL_RX))
iwl_dbg_report_frame(priv, rx_start, len, header, 1);
#endif
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(rx_start->phy_flags &
RX_RES_PHY_FLAGS_ANTENNA_MSK) >> 4;
/* set the preamble flag if appropriate */
if (rx_start->phy_flags & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK)
rx_status.flag |= RX_FLAG_SHORTPRE;
network_packet = iwl_is_network_packet(priv, header);
if (network_packet) {
priv->last_rx_rssi = rx_status.signal;
priv->last_beacon_time = priv->ucode_beacon_time;
priv->last_tsf = le64_to_cpu(rx_start->timestamp);
}
fc = le16_to_cpu(header->frame_control);
switch (fc & IEEE80211_FCTL_FTYPE) {
case IEEE80211_FTYPE_MGMT:
case IEEE80211_FTYPE_DATA:
if (priv->iw_mode == NL80211_IFTYPE_AP)
iwl_update_ps_mode(priv, fc & IEEE80211_FCTL_PM,
header->addr2);
/* fall through */
default:
iwl_pass_packet_to_mac80211(priv, include_phy, rxb,
&rx_status);
break;
}
}
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 = (struct iwl_rx_packet *)rxb->skb->data;
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);