rc.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright( c ) 2009-2012  Realtek Corporation.*/

#include "wifi.h"
#include "base.h"
#include "rc.h"

/*
 *Finds the highest rate index we can use
 *if skb is special data like DHCP/EAPOL, we set should
 *it to lowest rate CCK_1M, otherwise we set rate to
 *highest rate based on wireless mode used for iwconfig
 *show Tx rate.
 */
static u8 _rtl_rc_get_highest_rix( struct rtl_priv *rtlpriv,
				  struct ieee80211_sta *sta,
				  struct sk_buff *skb, bool not_data )
{
	struct rtl_hal *rtlhal = rtl_hal( rtlpriv );
	struct rtl_phy *rtlphy = &( rtlpriv->phy );
	struct rtl_sta_info *sta_entry = NULL;
	u16 wireless_mode = 0;
	u8 nss;
	struct ieee80211_tx_rate rate;

	switch ( get_rf_type( rtlphy ) ) {
	case RF_4T4R:
		nss = 4;
		break;
	case RF_3T3R:
		nss = 3;
		break;
	case RF_2T2R:
		nss = 2;
		break;
	default:
		nss = 1;
		break;
	}

	/*
	 *this rate is no use for true rate, firmware
	 *will control rate at all it just used for
	 *1.show in iwconfig in B/G mode
	 *2.in rtl_get_tcb_desc when we check rate is
	 *      1M we will not use FW rate but user rate.
	 */

	if ( sta ) {
		sta_entry = ( struct rtl_sta_info * )sta->drv_priv;
		wireless_mode = sta_entry->wireless_mode;
	}

	if ( rtl_is_special_data( rtlpriv->mac80211.hw, skb, true, false ) ||
	    not_data ) {
		return 0;
	} else {
		if ( rtlhal->current_bandtype == BAND_ON_2_4G ) {
			if ( wireless_mode == WIRELESS_MODE_B ) {
				return B_MODE_MAX_RIX;
			} else if ( wireless_mode == WIRELESS_MODE_G ) {
				return G_MODE_MAX_RIX;
			} else if ( wireless_mode == WIRELESS_MODE_N_24G ) {
				if ( nss == 1 )
					return N_MODE_MCS7_RIX;
				else
					return N_MODE_MCS15_RIX;
			} else if ( wireless_mode == WIRELESS_MODE_AC_24G ) {
				if ( sta->bandwidth == IEEE80211_STA_RX_BW_20 ) {
					ieee80211_rate_set_vht( &rate,
							       AC_MODE_MCS8_RIX,
							       nss );
					goto out;
				} else {
					ieee80211_rate_set_vht( &rate,
							       AC_MODE_MCS9_RIX,
							       nss );
					goto out;
				}
			}
			return 0;
		} else {
			if ( wireless_mode == WIRELESS_MODE_A ) {
				return A_MODE_MAX_RIX;
			} else if ( wireless_mode == WIRELESS_MODE_N_5G ) {
				if ( nss == 1 )
					return N_MODE_MCS7_RIX;
				else
					return N_MODE_MCS15_RIX;
			} else if ( wireless_mode == WIRELESS_MODE_AC_5G ) {
				if ( sta->bandwidth == IEEE80211_STA_RX_BW_20 ) {
					ieee80211_rate_set_vht( &rate,
							       AC_MODE_MCS8_RIX,
							       nss );
					goto out;
				} else {
					ieee80211_rate_set_vht( &rate,
							       AC_MODE_MCS9_RIX,
							       nss );
					goto out;
				}
			}
			return 0;
		}
	}

out:
	return rate.idx;
}

static void _rtl_rc_rate_set_series( struct rtl_priv *rtlpriv,
				    struct ieee80211_sta *sta,
				    struct ieee80211_tx_rate *rate,
				    struct ieee80211_tx_rate_control *txrc,
				    u8 tries, s8 rix, int rtsctsenable,
				    bool not_data )
{
	struct rtl_mac *mac = rtl_mac( rtlpriv );
	struct rtl_sta_info *sta_entry = NULL;
	u16 wireless_mode = 0;
	u8 sgi_20 = 0, sgi_40 = 0, sgi_80 = 0;

	if ( sta ) {
		sgi_20 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_20;
		sgi_40 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40;
		sgi_80 = sta->vht_cap.cap & IEEE80211_VHT_CAP_SHORT_GI_80;
		sta_entry = ( struct rtl_sta_info * )sta->drv_priv;
		wireless_mode = sta_entry->wireless_mode;
	}
	rate->count = tries;
	rate->idx = rix >= 0x00 ? rix : 0x00;

	if ( !not_data ) {
		if ( txrc->short_preamble )
			rate->flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
		if ( mac->opmode == NL80211_IFTYPE_AP ||
			mac->opmode == NL80211_IFTYPE_ADHOC ) {
			if ( sta && ( sta->ht_cap.cap &
				    IEEE80211_HT_CAP_SUP_WIDTH_20_40 ) )
				rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
			if ( sta && sta->vht_cap.vht_supported )
				rate->flags |= IEEE80211_TX_RC_80_MHZ_WIDTH;
		} else {
			if ( mac->bw_80 )
				rate->flags |= IEEE80211_TX_RC_80_MHZ_WIDTH;
			else if ( mac->bw_40 )
				rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
		}

		if ( sgi_20 || sgi_40 || sgi_80 )
			rate->flags |= IEEE80211_TX_RC_SHORT_GI;
		if ( sta && sta->ht_cap.ht_supported &&
		    ( wireless_mode == WIRELESS_MODE_N_5G ||
		     wireless_mode == WIRELESS_MODE_N_24G ) )
			rate->flags |= IEEE80211_TX_RC_MCS;
		if ( sta && sta->vht_cap.vht_supported &&
		    ( wireless_mode == WIRELESS_MODE_AC_5G ||
		     wireless_mode == WIRELESS_MODE_AC_24G ||
		     wireless_mode == WIRELESS_MODE_AC_ONLY ) )
			rate->flags |= IEEE80211_TX_RC_VHT_MCS;
	}
}

static void rtl_get_rate( void *ppriv, struct ieee80211_sta *sta,
			 void *priv_sta,
			 struct ieee80211_tx_rate_control *txrc )
{
	struct rtl_priv *rtlpriv = ppriv;
	struct sk_buff *skb = txrc->skb;
	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB( skb );
	struct ieee80211_tx_rate *rates = tx_info->control.rates;
	__le16 fc = rtl_get_fc( skb );
	u8 try_per_rate, i, rix;
	bool not_data = !ieee80211_is_data( fc );

	rix = _rtl_rc_get_highest_rix( rtlpriv, sta, skb, not_data );
	try_per_rate = 1;
	_rtl_rc_rate_set_series( rtlpriv, sta, &rates[0], txrc,
				try_per_rate, rix, 1, not_data );

	if ( !not_data ) {
		for ( i = 1; i < 4; i++ )
			_rtl_rc_rate_set_series( rtlpriv, sta, &rates[i],
						txrc, i, ( rix - i ), 1,
						not_data );
	}
}

static bool _rtl_tx_aggr_check( struct rtl_priv *rtlpriv,
			       struct rtl_sta_info *sta_entry, u16 tid )
{
	struct rtl_mac *mac = rtl_mac( rtlpriv );

	if ( mac->act_scanning )
		return false;

	if ( mac->opmode == NL80211_IFTYPE_STATION &&
	    mac->cnt_after_linked < 3 )
		return false;

	if ( sta_entry->tids[tid].agg.agg_state == RTL_AGG_STOP )
		return true;

	return false;
}

/*mac80211 Rate Control callbacks*/
static void rtl_tx_status( void *ppriv,
			  struct ieee80211_supported_band *sband,
			  struct ieee80211_sta *sta, void *priv_sta,
			  struct sk_buff *skb )
{
	struct rtl_priv *rtlpriv = ppriv;
	struct rtl_mac *mac = rtl_mac( rtlpriv );
	struct ieee80211_hdr *hdr = rtl_get_hdr( skb );
	__le16 fc = rtl_get_fc( skb );
	struct rtl_sta_info *sta_entry;

	if ( !priv_sta || !ieee80211_is_data( fc ) )
		return;

	if ( rtl_is_special_data( mac->hw, skb, true, true ) )
		return;

	if ( is_multicast_ether_addr( ieee80211_get_DA( hdr ) ) ||
	    is_broadcast_ether_addr( ieee80211_get_DA( hdr ) ) )
		return;

	if ( sta ) {
		/* Check if aggregation has to be enabled for this tid */
		sta_entry = ( struct rtl_sta_info * )sta->drv_priv;
		if ( sta->ht_cap.ht_supported &&
		    !( skb->protocol == cpu_to_be16( ETH_P_PAE ) ) ) {
			if ( ieee80211_is_data_qos( fc ) ) {
				u8 tid = rtl_get_tid( skb );

				if ( _rtl_tx_aggr_check( rtlpriv, sta_entry,
						       tid ) ) {
					sta_entry->tids[tid].agg.agg_state =
						RTL_AGG_PROGRESS;
					ieee80211_start_tx_ba_session( sta, tid,
								      5000 );
				}
			}
		}
	}
}

static void rtl_rate_init( void *ppriv,
			  struct ieee80211_supported_band *sband,
			  struct cfg80211_chan_def *chandef,
			  struct ieee80211_sta *sta, void *priv_sta )
{
}

static void rtl_rate_update( void *ppriv,
			    struct ieee80211_supported_band *sband,
			    struct cfg80211_chan_def *chandef,
			    struct ieee80211_sta *sta, void *priv_sta,
			    u32 changed )
{
}

static void *rtl_rate_alloc( struct ieee80211_hw *hw )
{
	struct rtl_priv *rtlpriv = rtl_priv( hw );
	return rtlpriv;
}

static void rtl_rate_free( void *rtlpriv )
{
	return;
}

static void *rtl_rate_alloc_sta( void *ppriv,
				struct ieee80211_sta *sta, gfp_t gfp )
{
	struct rtl_priv *rtlpriv = ppriv;
	struct rtl_rate_priv *rate_priv;

	rate_priv = kzalloc( sizeof( *rate_priv ), gfp );
	if ( !rate_priv )
		return NULL;

	rtlpriv->rate_priv = rate_priv;

	return rate_priv;
}

static void rtl_rate_free_sta( void *rtlpriv,
			      struct ieee80211_sta *sta, void *priv_sta )
{
	struct rtl_rate_priv *rate_priv = priv_sta;

	kfree( rate_priv );
}

static const struct rate_control_ops rtl_rate_ops = {
	.name = "rtl_rc",
	.alloc = rtl_rate_alloc,
	.free = rtl_rate_free,
	.alloc_sta = rtl_rate_alloc_sta,
	.free_sta = rtl_rate_free_sta,
	.rate_init = rtl_rate_init,
	.rate_update = rtl_rate_update,
	.tx_status = rtl_tx_status,
	.get_rate = rtl_get_rate,
};

int rtl_rate_control_register( void )
{
	return ieee80211_rate_control_register( &rtl_rate_ops );
}

void rtl_rate_control_unregister( void )
{
	ieee80211_rate_control_unregister( &rtl_rate_ops );
}