[PATCH 1/2] rt2x00: configure different txdesc parameters for non HT channel

[PATCH 1/2] rt2x00: configure different txdesc parameters for non HT channel

[Stanislaw Gruszka]

This is needed when we are concted to non 11n AP.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
---
 drivers/net/wireless/rt2x00/rt2x00.h       |    1 +
 drivers/net/wireless/rt2x00/rt2x00config.c |    5 +++++
 drivers/net/wireless/rt2x00/rt2x00queue.c  |   14 ++++++++++++++
 3 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 471f87c..8de9bfc 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -692,6 +692,7 @@ enum rt2x00_state_flags {
 	 */
 	CONFIG_CHANNEL_HT40,
 	CONFIG_POWERSAVING,
+	CONFIG_HT_DISABLED,
 
 	/*
 	 * Mark we currently are sequentially reading TX_STA_FIFO register
diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c
index 293676b..e7361d9 100644
--- a/drivers/net/wireless/rt2x00/rt2x00config.c
+++ b/drivers/net/wireless/rt2x00/rt2x00config.c
@@ -217,6 +217,11 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev,
 	libconf.conf = conf;
 
 	if (ieee80211_flags & IEEE80211_CONF_CHANGE_CHANNEL) {
+		if (!conf_is_ht(conf))
+			set_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags);
+		else
+			clear_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags);
+
 		if (conf_is_ht40(conf)) {
 			set_bit(CONFIG_CHANNEL_HT40, &rt2x00dev->flags);
 			hw_value = rt2x00ht_center_channel(rt2x00dev, conf);
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index 9b1b2b7..f7403cf 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -320,6 +320,20 @@ static void rt2x00queue_create_tx_descriptor_ht(struct rt2x00_dev *rt2x00dev,
 		txdesc->u.ht.wcid = sta_priv->wcid;
 	}
 
+	if (test_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags)) {
+		if (ieee80211_is_beacon(hdr->frame_control))
+			txdesc->u.ht.txop = TXOP_PIFS;
+		else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
+			txdesc->u.ht.txop = TXOP_SIFS;
+		else
+			txdesc->u.ht.txop = TXOP_BACKOFF;
+
+		txdesc->u.ht.mcs = txrate->idx;
+
+		/* Left zero on all other settings. */
+		return;
+	}
+
 	txdesc->u.ht.ba_size = 7;	/* FIXME: What value is needed? */
 
 	/*
-- 
1.7.1

[PATCH 2/2] rt2x00: do not generate seqno in h/w if QOS is disabled

[Stanislaw Gruszka]

This is workaround H/W or F/W bug, see in code comments. Without the fix
ping can receive duplicated ICMP frames while associated with legacy AP.

Reported-by: Walter Goldens <goldenstranger@yahoo.com>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
---
 drivers/net/wireless/rt2x00/rt2x00.h      |    1 +
 drivers/net/wireless/rt2x00/rt2x00mac.c   |   10 ++++++++++
 drivers/net/wireless/rt2x00/rt2x00queue.c |   15 +++++++++++++--
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 8de9bfc..5583214 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -693,6 +693,7 @@ enum rt2x00_state_flags {
 	CONFIG_CHANNEL_HT40,
 	CONFIG_POWERSAVING,
 	CONFIG_HT_DISABLED,
+	CONFIG_QOS_DISABLED,
 
 	/*
 	 * Mark we currently are sequentially reading TX_STA_FIFO register
diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index 2df2eb6..b49773e 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -709,9 +709,19 @@ void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
 			rt2x00dev->intf_associated--;
 
 		rt2x00leds_led_assoc(rt2x00dev, !!rt2x00dev->intf_associated);
+
+		clear_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags);
 	}
 
 	/*
+	 * Check for access point which do not support 802.11e . We have to
+	 * generate data frames sequence number in S/W for such AP, because
+	 * of H/W bug.
+	 */
+	if (changes & BSS_CHANGED_QOS && !bss_conf->qos)
+		set_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags);
+
+	/*
 	 * When the erp information has changed, we should perform
 	 * additional configuration steps. For all other changes we are done.
 	 */
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index f7403cf..5019a3e 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -213,8 +213,19 @@ static void rt2x00queue_create_tx_descriptor_seq(struct rt2x00_dev *rt2x00dev,
 
 	__set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
 
-	if (!test_bit(REQUIRE_SW_SEQNO, &rt2x00dev->cap_flags))
-		return;
+	if (!test_bit(REQUIRE_SW_SEQNO, &rt2x00dev->cap_flags)) {
+		/*
+		 * rt2800 has a H/W (or F/W) bug, device incorrectly increase
+		 * seqno on retransmited data (non-QOS) frames. To workaround
+		 * the problem let's generate seqno in software if QOS is
+		 * disabled.
+		 */
+		if (test_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags))
+			__clear_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
+		else
+			/* H/W will generate sequence number */
+			return;
+	}
 
 	/*
 	 * The hardware is not able to insert a sequence number. Assign a
-- 
1.7.1

Re: [PATCH 1/2] rt2x00: configure different txdesc parameters for non HT channel

[Helmut Schaa]

Hi Stanislaw,

On Mon, Apr 2, 2012 at 1:21 PM, Stanislaw Gruszka <sgruszka@redhat.com> wrote:
> This is needed when we are concted to non 11n AP.
>
> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
> ---
>  drivers/net/wireless/rt2x00/rt2x00.h       |    1 +
>  drivers/net/wireless/rt2x00/rt2x00config.c |    5 +++++
>  drivers/net/wireless/rt2x00/rt2x00queue.c  |   14 ++++++++++++++
>  3 files changed, 20 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
> index 471f87c..8de9bfc 100644
> --- a/drivers/net/wireless/rt2x00/rt2x00.h
> +++ b/drivers/net/wireless/rt2x00/rt2x00.h
> @@ -692,6 +692,7 @@ enum rt2x00_state_flags {
>         */
>        CONFIG_CHANNEL_HT40,
>        CONFIG_POWERSAVING,
> +       CONFIG_HT_DISABLED,
>
>        /*
>         * Mark we currently are sequentially reading TX_STA_FIFO register
> diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c
> index 293676b..e7361d9 100644
> --- a/drivers/net/wireless/rt2x00/rt2x00config.c
> +++ b/drivers/net/wireless/rt2x00/rt2x00config.c
> @@ -217,6 +217,11 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev,
>        libconf.conf = conf;
>
>        if (ieee80211_flags & IEEE80211_CONF_CHANGE_CHANNEL) {
> +               if (!conf_is_ht(conf))
> +                       set_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags);
> +               else
> +                       clear_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags);
> +
>                if (conf_is_ht40(conf)) {
>                        set_bit(CONFIG_CHANNEL_HT40, &rt2x00dev->flags);
>                        hw_value = rt2x00ht_center_channel(rt2x00dev, conf);
> diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
> index 9b1b2b7..f7403cf 100644
> --- a/drivers/net/wireless/rt2x00/rt2x00queue.c
> +++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
> @@ -320,6 +320,20 @@ static void rt2x00queue_create_tx_descriptor_ht(struct rt2x00_dev *rt2x00dev,
>                txdesc->u.ht.wcid = sta_priv->wcid;
>        }
>
> +       if (test_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags)) {
> +               if (ieee80211_is_beacon(hdr->frame_control))
> +                       txdesc->u.ht.txop = TXOP_PIFS;

Why should we use PIFS for the beacon? Is that what the ralink drivers
are doing?

> +               else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
> +                       txdesc->u.ht.txop = TXOP_SIFS;
> +               else
> +                       txdesc->u.ht.txop = TXOP_BACKOFF;
> +
> +               txdesc->u.ht.mcs = txrate->idx;
> +

This lacks short preamble handling. Something like:

if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
  txdesc->u.ht.mcs |= 0x08;

Actually, you could just shuffle the code a bit such that the rate setup
happens before all the HT stuff, no?

Helmut

Re: [PATCH 1/2] rt2x00: configure different txdesc parameters for non HT channel

[Stanislaw Gruszka]

Hello

On Mon, Apr 02, 2012 at 02:09:14PM +0200, Helmut Schaa wrote:
> Why should we use PIFS for the beacon? Is that what the ralink drivers
> are doing?
Hmm, seems that is my own invention. I thought that should be used for
beacons, but currently I can only find in docs, that this is only needed
for entering PCF.
 
> > +               else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
> > +                       txdesc->u.ht.txop = TXOP_SIFS;
> > +               else
> > +                       txdesc->u.ht.txop = TXOP_BACKOFF;
> > +
> > +               txdesc->u.ht.mcs = txrate->idx;
> > +
> 
> This lacks short preamble handling. Something like:
> 
> if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
>   txdesc->u.ht.mcs |= 0x08;
> 
> Actually, you could just shuffle the code a bit such that the rate setup
> happens before all the HT stuff, no?
Make sense.

Stanislaw

Re: [PATCH 1/2] rt2x00: configure different txdesc parameters for non HT channel

[Helmut Schaa]

On Mon, Apr 2, 2012 at 2:35 PM, Stanislaw Gruszka <sgruszka@redhat.com> wrote:
> On Mon, Apr 02, 2012 at 02:09:14PM +0200, Helmut Schaa wrote:
>> Why should we use PIFS for the beacon? Is that what the ralink drivers
>> are doing?
> Hmm, seems that is my own invention. I thought that should be used for
> beacons, but currently I can only find in docs, that this is only needed
> for entering PCF.

Ok, so if we're running in non-HT mode we could just always stick to
TXOP_BACKOFF and only use SIFS for bursts? Makes sense I guess.

Thanks,
Helmut

Re: [PATCH 2/2] rt2x00: do not generate seqno in h/w if QOS is disabled

[Helmut Schaa]

On Mon, Apr 2, 2012 at 1:21 PM, Stanislaw Gruszka <sgruszka@redhat.com> wrote:
> This is workaround H/W or F/W bug, see in code comments. Without the fix
> ping can receive duplicated ICMP frames while associated with legacy AP.
>
> Reported-by: Walter Goldens <goldenstranger@yahoo.com>
> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>

I don't have a better idea right now :) so this workaround looks suitable to me.

Acked-by: Helmut Schaa <helmut.schaa@googlemail.com>

Thanks for tracking this down Stanislaw!

> ---
>  drivers/net/wireless/rt2x00/rt2x00.h      |    1 +
>  drivers/net/wireless/rt2x00/rt2x00mac.c   |   10 ++++++++++
>  drivers/net/wireless/rt2x00/rt2x00queue.c |   15 +++++++++++++--
>  3 files changed, 24 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
> index 8de9bfc..5583214 100644
> --- a/drivers/net/wireless/rt2x00/rt2x00.h
> +++ b/drivers/net/wireless/rt2x00/rt2x00.h
> @@ -693,6 +693,7 @@ enum rt2x00_state_flags {
>        CONFIG_CHANNEL_HT40,
>        CONFIG_POWERSAVING,
>        CONFIG_HT_DISABLED,
> +       CONFIG_QOS_DISABLED,
>
>        /*
>         * Mark we currently are sequentially reading TX_STA_FIFO register
> diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
> index 2df2eb6..b49773e 100644
> --- a/drivers/net/wireless/rt2x00/rt2x00mac.c
> +++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
> @@ -709,9 +709,19 @@ void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
>                        rt2x00dev->intf_associated--;
>
>                rt2x00leds_led_assoc(rt2x00dev, !!rt2x00dev->intf_associated);
> +
> +               clear_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags);
>        }
>
>        /*
> +        * Check for access point which do not support 802.11e . We have to
> +        * generate data frames sequence number in S/W for such AP, because
> +        * of H/W bug.
> +        */
> +       if (changes & BSS_CHANGED_QOS && !bss_conf->qos)
> +               set_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags);
> +
> +       /*
>         * When the erp information has changed, we should perform
>         * additional configuration steps. For all other changes we are done.
>         */
> diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
> index f7403cf..5019a3e 100644
> --- a/drivers/net/wireless/rt2x00/rt2x00queue.c
> +++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
> @@ -213,8 +213,19 @@ static void rt2x00queue_create_tx_descriptor_seq(struct rt2x00_dev *rt2x00dev,
>
>        __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
>
> -       if (!test_bit(REQUIRE_SW_SEQNO, &rt2x00dev->cap_flags))
> -               return;
> +       if (!test_bit(REQUIRE_SW_SEQNO, &rt2x00dev->cap_flags)) {
> +               /*
> +                * rt2800 has a H/W (or F/W) bug, device incorrectly increase
> +                * seqno on retransmited data (non-QOS) frames. To workaround
> +                * the problem let's generate seqno in software if QOS is
> +                * disabled.
> +                */
> +               if (test_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags))
> +                       __clear_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
> +               else
> +                       /* H/W will generate sequence number */
> +                       return;
> +       }
>
>        /*
>         * The hardware is not able to insert a sequence number. Assign a
> --
> 1.7.1
>
> --
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[PATCH 1/2 v2] rt2x00: configure different txdesc parameters for non HT channel

[Stanislaw Gruszka]

This is needed when we are concted to non 11n AP.

v1 -> v2: set correctly txdesc->u.ht.txop and txdesc->u.ht.mcs

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
---
 drivers/net/wireless/rt2x00/rt2x00.h       |    1 +
 drivers/net/wireless/rt2x00/rt2x00config.c |    5 +++++
 drivers/net/wireless/rt2x00/rt2x00queue.c  |   26 ++++++++++++++++++--------
 3 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 471f87c..8de9bfc 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -692,6 +692,7 @@ enum rt2x00_state_flags {
 	 */
 	CONFIG_CHANNEL_HT40,
 	CONFIG_POWERSAVING,
+	CONFIG_HT_DISABLED,
 
 	/*
 	 * Mark we currently are sequentially reading TX_STA_FIFO register
diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c
index 293676b..e7361d9 100644
--- a/drivers/net/wireless/rt2x00/rt2x00config.c
+++ b/drivers/net/wireless/rt2x00/rt2x00config.c
@@ -217,6 +217,11 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev,
 	libconf.conf = conf;
 
 	if (ieee80211_flags & IEEE80211_CONF_CHANGE_CHANNEL) {
+		if (!conf_is_ht(conf))
+			set_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags);
+		else
+			clear_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags);
+
 		if (conf_is_ht40(conf)) {
 			set_bit(CONFIG_CHANNEL_HT40, &rt2x00dev->flags);
 			hw_value = rt2x00ht_center_channel(rt2x00dev, conf);
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index 9b1b2b7..acd0133 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -320,14 +320,6 @@ static void rt2x00queue_create_tx_descriptor_ht(struct rt2x00_dev *rt2x00dev,
 		txdesc->u.ht.wcid = sta_priv->wcid;
 	}
 
-	txdesc->u.ht.ba_size = 7;	/* FIXME: What value is needed? */
-
-	/*
-	 * Only one STBC stream is supported for now.
-	 */
-	if (tx_info->flags & IEEE80211_TX_CTL_STBC)
-		txdesc->u.ht.stbc = 1;
-
 	/*
 	 * If IEEE80211_TX_RC_MCS is set txrate->idx just contains the
 	 * mcs rate to be used
@@ -351,6 +343,24 @@ static void rt2x00queue_create_tx_descriptor_ht(struct rt2x00_dev *rt2x00dev,
 			txdesc->u.ht.mcs |= 0x08;
 	}
 
+	if (test_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags)) {
+		if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
+			txdesc->u.ht.txop = TXOP_SIFS;
+		else
+			txdesc->u.ht.txop = TXOP_BACKOFF;
+
+		/* Left zero on all other settings. */
+		return;
+	}
+
+	txdesc->u.ht.ba_size = 7;	/* FIXME: What value is needed? */
+
+	/*
+	 * Only one STBC stream is supported for now.
+	 */
+	if (tx_info->flags & IEEE80211_TX_CTL_STBC)
+		txdesc->u.ht.stbc = 1;
+
 	/*
 	 * This frame is eligible for an AMPDU, however, don't aggregate
 	 * frames that are intended to probe a specific tx rate.
-- 
1.7.1