iwl-4965-rs.c

linux内核源码

/******************************************************************************
 *
 * Copyright(c) 2005 - 2007 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.
 *
 * Contact Information:
 * James P. Ketrenos <[e-mail]>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 *****************************************************************************/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/wireless.h>
#include <net/mac80211.h>
#include <net/ieee80211.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/delay.h>

#include <linux/workqueue.h>

#define IWL 4965

#include "../net/mac80211/ieee80211_rate.h"

#include "iwlwifi.h"
#include "iwl-helpers.h"

#define RS_NAME "iwl-4965-rs"

#define NUM_TRY_BEFORE_ANTENNA_TOGGLE 1
#define IWL_NUMBER_TRY      1
#define IWL_HT_NUMBER_TRY   3

#define IWL_RATE_MAX_WINDOW		62
#define IWL_RATE_HIGH_TH		10880
#define IWL_RATE_MIN_FAILURE_TH		6
#define IWL_RATE_MIN_SUCCESS_TH		8
#define IWL_RATE_DECREASE_TH		1920
#define IWL_RATE_INCREASE_TH            8960
#define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)        /*2 seconds */

static u8 rs_ht_to_legacy[] = {
	IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
	IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
	IWL_RATE_6M_INDEX,
	IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
	IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
	IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
	IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
};

struct iwl_rate {
	u32 rate_n_flags;
} __attribute__ ((packed));

struct iwl_rate_scale_data {
	u64 data;
	s32 success_counter;
	s32 success_ratio;
	s32 counter;
	s32 average_tpt;
	unsigned long stamp;
};

struct iwl_scale_tbl_info {
	enum iwl_table_type lq_type;
	enum iwl_antenna_type antenna_type;
	u8 is_SGI;
	u8 is_fat;
	u8 is_dup;
	u8 action;
	s32 *expected_tpt;
	struct iwl_rate current_rate;
	struct iwl_rate_scale_data win[IWL_RATE_COUNT];
};

struct iwl_rate_scale_priv {
	u8 active_tbl;
	u8 enable_counter;
	u8 stay_in_tbl;
	u8 search_better_tbl;
	s32 last_tpt;
	u32 table_count_limit;
	u32 max_failure_limit;
	u32 max_success_limit;
	u32 table_count;
	u32 total_failed;
	u32 total_success;
	u32 flush_timer;
	u8 action_counter;
	u8 antenna;
	u8 valid_antenna;
	u8 is_green;
	u8 is_dup;
	u8 phymode;
	u8 ibss_sta_added;
	u32 supp_rates;
	u16 active_rate;
	u16 active_siso_rate;
	u16 active_mimo_rate;
	u16 active_rate_basic;
	struct iwl_link_quality_cmd lq;
	struct iwl_scale_tbl_info lq_info[LQ_SIZE];
#ifdef CONFIG_MAC80211_DEBUGFS
	struct dentry *rs_sta_dbgfs_scale_table_file;
	struct dentry *rs_sta_dbgfs_stats_table_file;
	struct iwl_rate dbg_fixed;
	struct iwl_priv *drv;
#endif
};

static void rs_rate_scale_perform(struct iwl_priv *priv,
				   struct net_device *dev,
				   struct ieee80211_hdr *hdr,
				   struct sta_info *sta);
static void rs_fill_link_cmd(struct iwl_rate_scale_priv *lq_data,
			     struct iwl_rate *tx_mcs,
			     struct iwl_link_quality_cmd *tbl);


#ifdef CONFIG_MAC80211_DEBUGFS
static void rs_dbgfs_set_mcs(struct iwl_rate_scale_priv *rs_priv,
				struct iwl_rate *mcs, int index);
#else
static void rs_dbgfs_set_mcs(struct iwl_rate_scale_priv *rs_priv,
				struct iwl_rate *mcs, int index)
{}
#endif
static s32 expected_tpt_A[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
};

static s32 expected_tpt_G[IWL_RATE_COUNT] = {
	7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
};

static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
};

static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
};

static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
};

static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
};

static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
};

static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
};

static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
};

static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
	0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
};

static int iwl_lq_sync_callback(struct iwl_priv *priv,
				struct iwl_cmd *cmd, struct sk_buff *skb)
{
	/*We didn't cache the SKB; let the caller free it */
	return 1;
}

static inline u8 iwl_rate_get_rate(u32 rate_n_flags)
{
	return (u8)(rate_n_flags & 0xFF);
}

static int rs_send_lq_cmd(struct iwl_priv *priv,
			  struct iwl_link_quality_cmd *lq, u8 flags)
{
#ifdef CONFIG_IWLWIFI_DEBUG
	int i;
#endif
	int rc = -1;

	struct iwl_host_cmd cmd = {
		.id = REPLY_TX_LINK_QUALITY_CMD,
		.len = sizeof(struct iwl_link_quality_cmd),
		.meta.flags = flags,
		.data = lq,
	};

	if ((lq->sta_id == 0xFF) &&
	    (priv->iw_mode == IEEE80211_IF_TYPE_IBSS))
		return rc;

	if (lq->sta_id == 0xFF)
		lq->sta_id = IWL_AP_ID;

	IWL_DEBUG_RATE("lq station id 0x%x\n", lq->sta_id);
	IWL_DEBUG_RATE("lq dta 0x%X 0x%X\n",
		       lq->general_params.single_stream_ant_msk,
		       lq->general_params.dual_stream_ant_msk);
#ifdef CONFIG_IWLWIFI_DEBUG
	for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
		IWL_DEBUG_RATE("lq index %d 0x%X\n",
				i, lq->rs_table[i].rate_n_flags);
#endif

	if (flags & CMD_ASYNC)
		cmd.meta.u.callback = iwl_lq_sync_callback;

	if (iwl_is_associated(priv) && priv->assoc_station_added &&
	    priv->lq_mngr.lq_ready)
		rc = iwl_send_cmd(priv, &cmd);

	return rc;
}

static int rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
{
	window->data = 0;
	window->success_counter = 0;
	window->success_ratio = IWL_INVALID_VALUE;
	window->counter = 0;
	window->average_tpt = IWL_INVALID_VALUE;
	window->stamp = 0;

	return 0;
}

static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
			      int scale_index, s32 tpt, u32 status)
{
	int rc = 0;
	struct iwl_rate_scale_data *window = NULL;
	u64 mask;
	u8 win_size = IWL_RATE_MAX_WINDOW;
	s32 fail_count;

	if (scale_index < 0)
		return -1;

	if (scale_index >= IWL_RATE_COUNT)
		return -1;

	window = &(windows[scale_index]);

	if (window->counter >= win_size) {

		window->counter = win_size - 1;
		mask = 1;
		mask = (mask << (win_size - 1));
		if ((window->data & mask)) {
			window->data &= ~mask;
			window->success_counter = window->success_counter - 1;
		}
	}

	window->counter = window->counter + 1;
	mask = window->data;
	window->data = (mask << 1);
	if (status != 0) {
		window->success_counter = window->success_counter + 1;
		window->data |= 0x1;
	}

	if (window->counter > 0)
		window->success_ratio = 128 * (100 * window->success_counter)
					/ window->counter;
	else
		window->success_ratio = IWL_INVALID_VALUE;

	fail_count = window->counter - window->success_counter;

	if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
	    (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
		window->average_tpt = (window->success_ratio * tpt + 64) / 128;
	else
		window->average_tpt = IWL_INVALID_VALUE;

	window->stamp = jiffies;

	return rc;
}

int static rs_mcs_from_tbl(struct iwl_rate *mcs_rate,
			   struct iwl_scale_tbl_info *tbl,
			   int index, u8 use_green)
{
	int rc = 0;

	if (is_legacy(tbl->lq_type)) {
		mcs_rate->rate_n_flags = iwl_rates[index].plcp;
		if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
			mcs_rate->rate_n_flags |= RATE_MCS_CCK_MSK;

	} else if (is_siso(tbl->lq_type)) {
		if (index > IWL_LAST_OFDM_RATE)
			index = IWL_LAST_OFDM_RATE;
		 mcs_rate->rate_n_flags = iwl_rates[index].plcp_siso |
					  RATE_MCS_HT_MSK;
	} else {
		if (index > IWL_LAST_OFDM_RATE)
			index = IWL_LAST_OFDM_RATE;
		mcs_rate->rate_n_flags = iwl_rates[index].plcp_mimo |
					 RATE_MCS_HT_MSK;
	}

	switch (tbl->antenna_type) {
	case ANT_BOTH:
		mcs_rate->rate_n_flags |= RATE_MCS_ANT_AB_MSK;
		break;
	case ANT_MAIN:
		mcs_rate->rate_n_flags |= RATE_MCS_ANT_A_MSK;
		break;
	case ANT_AUX:
		mcs_rate->rate_n_flags |= RATE_MCS_ANT_B_MSK;
		break;
	case ANT_NONE:
		break;
	}

	if (is_legacy(tbl->lq_type))
		return rc;

	if (tbl->is_fat) {
		if (tbl->is_dup)
			mcs_rate->rate_n_flags |= RATE_MCS_DUP_MSK;
		else
			mcs_rate->rate_n_flags |= RATE_MCS_FAT_MSK;
	}
	if (tbl->is_SGI)
		mcs_rate->rate_n_flags |= RATE_MCS_SGI_MSK;

	if (use_green) {
		mcs_rate->rate_n_flags |= RATE_MCS_GF_MSK;
		if (is_siso(tbl->lq_type))
			mcs_rate->rate_n_flags &= ~RATE_MCS_SGI_MSK;
	}
	return rc;
}

static int rs_get_tbl_info_from_mcs(const struct iwl_rate *mcs_rate,
				    int phymode, struct iwl_scale_tbl_info *tbl,
				    int *rate_idx)
{
	int index;
	u32 ant_msk;

	index = iwl_rate_index_from_plcp(mcs_rate->rate_n_flags);

	if (index  == IWL_RATE_INVALID) {
		*rate_idx = -1;
		return -1;
	}
	tbl->is_SGI = 0;
	tbl->is_fat = 0;
	tbl->is_dup = 0;
	tbl->antenna_type = ANT_BOTH;

	if (!(mcs_rate->rate_n_flags & RATE_MCS_HT_MSK)) {
		ant_msk = (mcs_rate->rate_n_flags & RATE_MCS_ANT_AB_MSK);

		if (ant_msk == RATE_MCS_ANT_AB_MSK)
			tbl->lq_type = LQ_NONE;
		else {

			if (phymode == MODE_IEEE80211A)
				tbl->lq_type = LQ_A;
			else
				tbl->lq_type = LQ_G;

			if (mcs_rate->rate_n_flags & RATE_MCS_ANT_A_MSK)
				tbl->antenna_type = ANT_MAIN;
			else
				tbl->antenna_type = ANT_AUX;
		}
		*rate_idx = index;

	} else if (iwl_rate_get_rate(mcs_rate->rate_n_flags)
					<= IWL_RATE_SISO_60M_PLCP) {
		tbl->lq_type = LQ_SISO;

		ant_msk = (mcs_rate->rate_n_flags & RATE_MCS_ANT_AB_MSK);
		if (ant_msk == RATE_MCS_ANT_AB_MSK)
			tbl->lq_type = LQ_NONE;
		else {
			if (mcs_rate->rate_n_flags & RATE_MCS_ANT_A_MSK)
				tbl->antenna_type = ANT_MAIN;
			else
				tbl->antenna_type = ANT_AUX;
		}
		if (mcs_rate->rate_n_flags & RATE_MCS_SGI_MSK)
			tbl->is_SGI = 1;

		if ((mcs_rate->rate_n_flags & RATE_MCS_FAT_MSK) ||
		    (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK))
			tbl->is_fat = 1;

		if (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK)
			tbl->is_dup = 1;

		*rate_idx = index;
	} else {
		tbl->lq_type = LQ_MIMO;
		if (mcs_rate->rate_n_flags & RATE_MCS_SGI_MSK)
			tbl->is_SGI = 1;

		if ((mcs_rate->rate_n_flags & RATE_MCS_FAT_MSK) ||
		    (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK))
			tbl->is_fat = 1;

		if (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK)
			tbl->is_dup = 1;
		*rate_idx = index;
	}
	return 0;
}

static inline void rs_toggle_antenna(struct iwl_rate *new_rate,
				     struct iwl_scale_tbl_info *tbl)
{
	if (tbl->antenna_type == ANT_AUX) {
		tbl->antenna_type = ANT_MAIN;
		new_rate->rate_n_flags &= ~RATE_MCS_ANT_B_MSK;
		new_rate->rate_n_flags |= RATE_MCS_ANT_A_MSK;
	} else {
		tbl->antenna_type = ANT_AUX;
		new_rate->rate_n_flags &= ~RATE_MCS_ANT_A_MSK;
		new_rate->rate_n_flags |= RATE_MCS_ANT_B_MSK;
	}
}

static inline s8 rs_use_green(struct iwl_priv *priv)
{
	s8 rc = 0;
#ifdef CONFIG_IWLWIFI_HT
	if (!priv->is_ht_enabled || !priv->current_assoc_ht.is_ht)
		return 0;

	if ((priv->current_assoc_ht.is_green_field) &&
	    !(priv->current_assoc_ht.operating_mode & 0x4))
		rc = 1;
#endif	/*CONFIG_IWLWIFI_HT */
	return rc;
}

/**
 * rs_get_supported_rates - get the available rates
 *
 * if management frame or broadcast frame only return
 * basic available rates.
 *
 */
static void rs_get_supported_rates(struct iwl_rate_scale_priv *lq_data,
				   struct ieee80211_hdr *hdr,
				   enum iwl_table_type rate_type,
				   u16 *data_rate)
{
	if (is_legacy(rate_type))
		*data_rate = lq_data->active_rate;
	else {
		if (is_siso(rate_type))
			*data_rate = lq_data->active_siso_rate;
		else
			*data_rate = lq_data->active_mimo_rate;
	}

	if (hdr && is_multicast_ether_addr(hdr->addr1) &&
	    lq_data->active_rate_basic)
		*data_rate = lq_data->active_rate_basic;
}

static u16 rs_get_adjacent_rate(u8 index, u16 rate_mask, int rate_type)
{
	u8 high = IWL_RATE_INVALID;
	u8 low = IWL_RATE_INVALID;

	/* 802.11A or ht walks to the next literal adjascent rate in
	 * the rate table */
	if (is_a_band(rate_type) || !is_legacy(rate_type)) {
		int i;
		u32 mask;

		/* Find the previous rate that is in the rate mask */
		i = index - 1;
		for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
			if (rate_mask & mask) {
				low = i;
				break;
			}
		}

		/* Find the next rate that is in the rate mask */
		i = index + 1;
		for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
			if (rate_mask & mask) {
				high = i;
				break;
			}
		}

		return (high << 8) | low;
	}

	low = index;
	while (low != IWL_RATE_INVALID) {
		low = iwl_rates[low].prev_rs;
		if (low == IWL_RATE_INVALID)
			break;
		if (rate_mask & (1 << low))
			break;
		IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
	}

	high = index;
	while (high != IWL_RATE_INVALID) {
		high = iwl_rates[high].next_rs;
		if (high == IWL_RATE_INVALID)
			break;
		if (rate_mask & (1 << high))
			break;
		IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
	}

	return (high << 8) | low;
}

static int rs_get_lower_rate(struct iwl_rate_scale_priv *lq_data,
			     struct iwl_scale_tbl_info *tbl, u8 scale_index,
			     u8 ht_possible, struct iwl_rate *mcs_rate)
{
	s32 low;
	u16 rate_mask;
	u16 high_low;
	u8 switch_to_legacy = 0;
	u8 is_green = lq_data->is_green;

	/* check if we need to switch from HT to legacy rates.
	 * assumption is that mandatory rates (1Mbps or 6Mbps)
	 * are always supported (spec demand) */
	if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
		switch_to_legacy = 1;
		scale_index = rs_ht_to_legacy[scale_index];
		if (lq_data->phymode == MODE_IEEE80211A)
			tbl->lq_type = LQ_A;
		else
			tbl->lq_type = LQ_G;

		if ((tbl->antenna_type == ANT_BOTH) ||
		    (tbl->antenna_type == ANT_NONE))
			tbl->antenna_type = ANT_MAIN;