RE: Patching ath9k/mac80211 to change MAC layer features

RE: Patching ath9k/mac80211 to change MAC layer features

[Fred Matthews]

[-- Attachment #1: Type: text/plain, Size: 1647 bytes --]


Hi,

I would appreciate if anyone can help me with my previous query as soon as possible.
Thanks!
From: fredmm@hotmail.co.uk
To: linux-kernel@vger.kernel.org; linux-wireless@vger.kernel.org; ath9k-devel@venema.h4ckr.net; ath9k-devel@lists.ath9k
Subject: Patching ath9k/mac80211 to change MAC layer features
Date: Thu, 16 Jun 2011 21:39:09 +0100


Hello all,

I have a query regarding patching ath9k/mac80211 to change MAC layer features and I would be most grateful if someone can assist.

I need to patch ath9k so that I can be able to modify/fix the A-MPDU aggregation frame length and other parameters such that they can be configured at runtime via debugfs. I made a newbie attempt at trying to change the aggregate length (attached), but I am unsure of the correctness/efficiency  - when applied throughput varies with different frame lengths entered but I can't be sure if its actually changing the aggregation length (passes the framelen/aggr_limit). Hence I would be very grateful if someone can assist in the correct way of doing this (possibly directly via mac80211). 

Also if the ampdu aggregate length is changed I believe the number/length of the subframes of the aggregate stays constant (at the default which is 32). I try to change this in my patch as well as the maximum software retries by just changing the default definition in ath9k.h, thus is there a (more) correct/better way of changing these. Finally, how can I patch the driver to be able to disable Block-Acks/aggregation via debugfs or otherwise. 

I highly appreciate, help in any of the above, as well as other advice,
Many thanks
  		 	   		  

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: aggr+subframe+retry_change_attempt.patch --]
[-- Type: text/x-patch, Size: 7987 bytes --]

diff -Naur a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
--- a/drivers/net/wireless/ath/ath9k/ath9k.h	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h	2011-06-02 19:59:28.043327000 +0100
@@ -137,7 +137,7 @@
 #define ATH_AGGR_ENCRYPTDELIM      10
 /* minimum h/w qdepth to be sustained to maximize aggregation */
 #define ATH_AGGR_MIN_QDEPTH        2
-#define ATH_AMPDU_SUBFRAME_DEFAULT 32
+#define ATH_AMPDU_SUBFRAME_DEFAULT sc->debug.subframe_size
 
 #define IEEE80211_SEQ_SEQ_SHIFT    4
 #define IEEE80211_SEQ_MAX          4096
@@ -537,7 +537,7 @@
 #define DEFAULT_CACHELINE       32
 #define ATH_REGCLASSIDS_MAX     10
 #define ATH_CABQ_READY_TIME     80      /* % of beacon interval */
-#define ATH_MAX_SW_RETRIES      10
+#define ATH_MAX_SW_RETRIES      sc->debug.retry_limit
 #define ATH_CHAN_MAX            255
 
 #define ATH_TXPOWER_MAX         100     /* .5 dBm units */
diff -Naur a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
--- a/drivers/net/wireless/ath/ath9k/debug.c	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/debug.c	2011-06-02 19:54:09.260320000 +0100
@@ -1045,6 +1048,162 @@
 	.llseek = default_llseek,
 };
 
+static ssize_t read_file_ampdu_len(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[32];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.ampdu_len);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_ampdu_len(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long ampdu_len;
+	char buf[32];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &ampdu_len))
+		return -EINVAL;
+
+	sc->debug.ampdu_len = ampdu_len;
+	return count;
+}
+
+static const struct file_operations fops_ampdu_len = {
+	.read = read_file_ampdu_len,
+	.write = write_file_ampdu_len,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+static ssize_t read_file_retry_limit(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[16];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.retry_limit);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_retry_limit(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long retry_limit;
+	char buf[16];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &retry_limit))
+		return -EINVAL;
+
+	sc->debug.retry_limit = retry_limit;
+	return count;
+}
+
+static const struct file_operations fops_retry_limit = {
+	.read = read_file_retry_limit,
+	.write = write_file_retry_limit,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+static ssize_t read_file_subframe_size(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[16];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.subframe_size);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_subframe_size(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long subframe_size;
+	char buf[16];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &subframe_size))
+		return -EINVAL;
+
+	sc->debug.subframe_size = subframe_size;
+	return count;
+}
+
+static const struct file_operations fops_subframe_size = {
+	.read = read_file_subframe_size,
+	.write = write_file_subframe_size,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+static ssize_t read_file_auto_ampdu(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[8];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.auto_ampdu);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_auto_ampdu(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long auto_ampdu;
+	char buf[8];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &auto_ampdu))
+		return -EINVAL;
+
+	sc->debug.auto_ampdu = auto_ampdu;
+	return count;
+}
+
+static const struct file_operations fops_auto_ampdu = {
+	.read = read_file_auto_ampdu,
+	.write = write_file_auto_ampdu,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
 static ssize_t read_file_regval(struct file *file, char __user *user_buf,
 			     size_t count, loff_t *ppos)
 {
@@ -1162,6 +1407,15 @@
 			    sc->debug.debugfs_phy, sc, &fops_tx_chainmask);
 	debugfs_create_file("regidx", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
 			    sc, &fops_regidx);
+			    
+	debugfs_create_file("ampdu_len", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_ampdu_len);
+	debugfs_create_file("retry_limit", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_retry_limit);
+	debugfs_create_file("subframe_size", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_subframe_size);
+	debugfs_create_file("auto_ampdu[0:OFF,1:ON]", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_auto_ampdu);
 	debugfs_create_file("regval", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
 			    sc, &fops_regval);
 	debugfs_create_bool("ignore_extcca", S_IRUSR | S_IWUSR,
@@ -1177,5 +1302,8 @@
 			   sc->debug.debugfs_phy, &sc->sc_ah->gpio_val);
 
 	sc->debug.regidx = 0;
+	sc->debug.auto_ampdu = 1;
+ 	sc->debug.ampdu_len = ATH_AMPDU_LIMIT_MAX;
+ 	sc->debug.retry_limit = 10;
 	return 0;
 }
 
diff -Naur a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
--- a/drivers/net/wireless/ath/ath9k/debug.h	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/debug.h	2011-06-02 19:55:33.332337000 +0100
@@ -179,6 +180,10 @@
 struct ath9k_debug {
 	struct dentry *debugfs_phy;
 	u32 regidx;
+	u32 ampdu_len;
+	u16 retry_limit;
+	u16 subframe_size;
+	u8 auto_ampdu;
 	struct ath_stats stats;
 };
 
diff -Naur a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
--- a/drivers/net/wireless/ath/ath9k/xmit.c	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/xmit.c	2011-06-02 19:58:19.647347000 +0100
@@ -616,8 +616,12 @@
 			if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
 				modeidx++;
 
-			frmlen = ath_max_4ms_framelen[modeidx][rates[i].idx];
-			max_4ms_framelen = min(max_4ms_framelen, frmlen);
+				frmlen = ath_max_4ms_framelen[modeidx][rates[i].idx];
+				
+			if (sc->debug.auto_ampdu==1) 
+				max_4ms_framelen = min(max_4ms_framelen, frmlen);
+			else 
+				max_4ms_framelen = sc->debug.ampdu_len;
 		}
 	}
 
@@ -641,7 +645,7 @@
 	 * The IE, however can hold up to 65536, which shows up here
 	 * as zero. Ignore 65536 since we  are constrained by hw.
 	 */
-	if (tid->an->maxampdu)
+	if (sc->debug.auto_ampdu==1 && tid->an->maxampdu)
 		aggr_limit = min(aggr_limit, tid->an->maxampdu);
 
 	return aggr_limit;

Re: [ath9k-devel] Patching ath9k/mac80211 to change MAC layer features

[Mohammed Shafi]

On Fri, Jun 17, 2011 at 2:09 AM, Fred Matthews <fredmm@hotmail.co.uk> wrote:
> Hello all,
>
>
> I have a query regarding patching ath9k/mac80211 to change MAC layer
> features and I would be most grateful if someone can assist.
>
>
> I need to patch ath9k so that I can be able to modify/fix the A-MPDU
> aggregation frame length and other parameters such that they can be
> configured at runtime via debugfs. I made a newbie attempt at trying to
> change the aggregate length (attached), but I am unsure of the
> correctness/efficiency  - when applied throughput varies with different
> frame lengths entered but I can't be sure if its actually changing the
> aggregation length (passes the framelen/aggr_limit). Hence I would be very
> grateful if someone can assist in the correct way of doing this (possibly
> directly via mac80211).
>
>
>
> Also if the ampdu aggregate length is changed I believe the number/length of
> the subframes of the aggregate stays constant (at the default which is
> 32). I try to change this in my patch as well as the maximum software
> retries by just changing the default definition in ath9k.h, thus is there a
> (more) correct/better way of changing these. Finally, how can I patch the
> driver to be able to disable Block-Acks/aggregation via debugfs or
> otherwise.


to disable aggregation in the driver, please try this
diff --git a/drivers/net/wireless/ath/ath9k/init.c
b/drivers/net/wireless/ath/ath9k/init.c
index d4b166c..e0175d0 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -524,8 +524,6 @@ static void ath9k_init_misc(struct ath_softc *sc)
        sc->config.txpowlimit = ATH_TXPOWER_MAX;

        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT) {
-               sc->sc_flags |= SC_OP_TXAGGR;
-               sc->sc_flags |= SC_OP_RXAGGR;
        }

        common->tx_chainmask = sc->sc_ah->caps.tx_chainmask;

if you want only tx-aggregation to be disabled , please comment out only that.
also you can completely disable HT by
diff --git a/drivers/net/wireless/ath/ath9k/hw.c
b/drivers/net/wireless/ath/ath9k/hw.c
index 6de2655..696b4cc 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1915,10 +1915,7 @@ int ath9k_hw_fill_cap_info(struct ath_hw *ah)

        common->crypt_caps |= ATH_CRYPT_CAP_CIPHER_AESCCM;

-       if (ah->hw_version.devid != AR2427_DEVID_PCIE)
-               pCap->hw_caps |= ATH9K_HW_CAP_HT;
-       else
-               pCap->hw_caps &= ~ATH9K_HW_CAP_HT;
+       pCap->hw_caps &= ~ATH9K_HW_CAP_HT;

        if (AR_SREV_9271(ah))
                pCap->num_gpio_pins = AR9271_NUM_GPIO;




>
>
>
> I highly appreciate, help in any of the above, as well as other advice,
> Many thanks
>
> _______________________________________________
> ath9k-devel mailing list
> ath9k-devel@lists.ath9k.org
> https://lists.ath9k.org/mailman/listinfo/ath9k-devel
>
>



-- 
shafi

Re: [ath9k-devel] Patching ath9k/mac80211 to change MAC layer features

[Fred Matthews]

[-- Attachment #1: Type: text/plain, Size: 4995 bytes --]

Hi all,

Much appreciated Mohammed Shafi, disabling aggregation works when
replacing those lines with
 sc->sc_flags &= ~SC_OP_TXAGGR;
 sc->sc_flags &= ~SC_OP_RXAGGR;
only issue is I must always recompile compat-wireless to
re-enable/disable it again. I tried to port it using debugfs to be
able to enable and disable at runtime but ath9k kept rebooting.

Also I would be very grateful if someone can help regarding my
attached patch and previous query:

------------
 need to patch ath9k so that I can be able to modify/fix the A-MPDU
aggregation frame length and other parameters such that they can be
configured at runtime via debugfs. I made a newbie attempt at trying
to change the aggregate length (attached), but I am unsure of the
correctness/efficiency  - when applied throughput varies with
different frame lengths entered but I can't be sure if its actually
changing the aggregation length (passes the framelen/aggr_limit).
Hence I would be very grateful if someone can assist in the correct
way of doing this (possibly directly via mac80211).


Also if the ampdu aggregate length is changed I believe the
number/length of the subframes of the aggregate stays constant (at the
default which is 32). I try to change this in my patch as well as the
maximum software retries by just changing the default definition in
ath9k.h, thus is there a (more) correct/better way of changing these.
Finally, how can I patch the driver to be able to disable Block-Acks
via debugfs or otherwise.
---------------

Thank you very much



On Mon, Jun 20, 2011 at 9:15 AM, Mohammed Shafi
<shafi.wireless@gmail.com> wrote:
> On Fri, Jun 17, 2011 at 2:09 AM, Fred Matthews <fredmm@hotmail.co.uk> wrote:
>> Hello all,
>>
>>
>> I have a query regarding patching ath9k/mac80211 to change MAC layer
>> features and I would be most grateful if someone can assist.
>>
>>
>> I need to patch ath9k so that I can be able to modify/fix the A-MPDU
>> aggregation frame length and other parameters such that they can be
>> configured at runtime via debugfs. I made a newbie attempt at trying to
>> change the aggregate length (attached), but I am unsure of the
>> correctness/efficiency  - when applied throughput varies with different
>> frame lengths entered but I can't be sure if its actually changing the
>> aggregation length (passes the framelen/aggr_limit). Hence I would be very
>> grateful if someone can assist in the correct way of doing this (possibly
>> directly via mac80211).
>>
>>
>>
>> Also if the ampdu aggregate length is changed I believe the number/length of
>> the subframes of the aggregate stays constant (at the default which is
>> 32). I try to change this in my patch as well as the maximum software
>> retries by just changing the default definition in ath9k.h, thus is there a
>> (more) correct/better way of changing these. Finally, how can I patch the
>> driver to be able to disable Block-Acks/aggregation via debugfs or
>> otherwise.
>
>
> to disable aggregation in the driver, please try this
> diff --git a/drivers/net/wireless/ath/ath9k/init.c
> b/drivers/net/wireless/ath/ath9k/init.c
> index d4b166c..e0175d0 100644
> --- a/drivers/net/wireless/ath/ath9k/init.c
> +++ b/drivers/net/wireless/ath/ath9k/init.c
> @@ -524,8 +524,6 @@ static void ath9k_init_misc(struct ath_softc *sc)
>        sc->config.txpowlimit = ATH_TXPOWER_MAX;
>
>        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT) {
> -               sc->sc_flags |= SC_OP_TXAGGR;
> -               sc->sc_flags |= SC_OP_RXAGGR;
>        }
>
>        common->tx_chainmask = sc->sc_ah->caps.tx_chainmask;
>
> if you want only tx-aggregation to be disabled , please comment out only that.
> also you can completely disable HT by
> diff --git a/drivers/net/wireless/ath/ath9k/hw.c
> b/drivers/net/wireless/ath/ath9k/hw.c
> index 6de2655..696b4cc 100644
> --- a/drivers/net/wireless/ath/ath9k/hw.c
> +++ b/drivers/net/wireless/ath/ath9k/hw.c
> @@ -1915,10 +1915,7 @@ int ath9k_hw_fill_cap_info(struct ath_hw *ah)
>
>        common->crypt_caps |= ATH_CRYPT_CAP_CIPHER_AESCCM;
>
> -       if (ah->hw_version.devid != AR2427_DEVID_PCIE)
> -               pCap->hw_caps |= ATH9K_HW_CAP_HT;
> -       else
> -               pCap->hw_caps &= ~ATH9K_HW_CAP_HT;
> +       pCap->hw_caps &= ~ATH9K_HW_CAP_HT;
>
>        if (AR_SREV_9271(ah))
>                pCap->num_gpio_pins = AR9271_NUM_GPIO;
>
>
>
>
>>
>>
>>
>> I highly appreciate, help in any of the above, as well as other advice,
>> Many thanks
>>
>> _______________________________________________
>> ath9k-devel mailing list
>> ath9k-devel@lists.ath9k.org
>> https://lists.ath9k.org/mailman/listinfo/ath9k-devel
>>
>>
>
>
>
> --
> shafi
> --
> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

[-- Attachment #2: aggr+subframe+retry_change_attempt.patch --]
[-- Type: text/x-patch, Size: 7987 bytes --]

diff -Naur a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
--- a/drivers/net/wireless/ath/ath9k/ath9k.h	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h	2011-06-02 19:59:28.043327000 +0100
@@ -137,7 +137,7 @@
 #define ATH_AGGR_ENCRYPTDELIM      10
 /* minimum h/w qdepth to be sustained to maximize aggregation */
 #define ATH_AGGR_MIN_QDEPTH        2
-#define ATH_AMPDU_SUBFRAME_DEFAULT 32
+#define ATH_AMPDU_SUBFRAME_DEFAULT sc->debug.subframe_size
 
 #define IEEE80211_SEQ_SEQ_SHIFT    4
 #define IEEE80211_SEQ_MAX          4096
@@ -537,7 +537,7 @@
 #define DEFAULT_CACHELINE       32
 #define ATH_REGCLASSIDS_MAX     10
 #define ATH_CABQ_READY_TIME     80      /* % of beacon interval */
-#define ATH_MAX_SW_RETRIES      10
+#define ATH_MAX_SW_RETRIES      sc->debug.retry_limit
 #define ATH_CHAN_MAX            255
 
 #define ATH_TXPOWER_MAX         100     /* .5 dBm units */
diff -Naur a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
--- a/drivers/net/wireless/ath/ath9k/debug.c	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/debug.c	2011-06-02 19:54:09.260320000 +0100
@@ -1045,6 +1048,162 @@
 	.llseek = default_llseek,
 };
 
+static ssize_t read_file_ampdu_len(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[32];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.ampdu_len);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_ampdu_len(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long ampdu_len;
+	char buf[32];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &ampdu_len))
+		return -EINVAL;
+
+	sc->debug.ampdu_len = ampdu_len;
+	return count;
+}
+
+static const struct file_operations fops_ampdu_len = {
+	.read = read_file_ampdu_len,
+	.write = write_file_ampdu_len,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+static ssize_t read_file_retry_limit(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[16];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.retry_limit);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_retry_limit(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long retry_limit;
+	char buf[16];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &retry_limit))
+		return -EINVAL;
+
+	sc->debug.retry_limit = retry_limit;
+	return count;
+}
+
+static const struct file_operations fops_retry_limit = {
+	.read = read_file_retry_limit,
+	.write = write_file_retry_limit,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+static ssize_t read_file_subframe_size(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[16];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.subframe_size);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_subframe_size(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long subframe_size;
+	char buf[16];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &subframe_size))
+		return -EINVAL;
+
+	sc->debug.subframe_size = subframe_size;
+	return count;
+}
+
+static const struct file_operations fops_subframe_size = {
+	.read = read_file_subframe_size,
+	.write = write_file_subframe_size,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
+static ssize_t read_file_auto_ampdu(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	char buf[8];
+	unsigned int len;
+
+	len = sprintf(buf, "%u\n", sc->debug.auto_ampdu);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_auto_ampdu(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	unsigned long auto_ampdu;
+	char buf[8];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &auto_ampdu))
+		return -EINVAL;
+
+	sc->debug.auto_ampdu = auto_ampdu;
+	return count;
+}
+
+static const struct file_operations fops_auto_ampdu = {
+	.read = read_file_auto_ampdu,
+	.write = write_file_auto_ampdu,
+	.open = ath9k_debugfs_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
 static ssize_t read_file_regval(struct file *file, char __user *user_buf,
 			     size_t count, loff_t *ppos)
 {
@@ -1162,6 +1407,15 @@
 			    sc->debug.debugfs_phy, sc, &fops_tx_chainmask);
 	debugfs_create_file("regidx", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
 			    sc, &fops_regidx);
+			    
+	debugfs_create_file("ampdu_len", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_ampdu_len);
+	debugfs_create_file("retry_limit", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_retry_limit);
+	debugfs_create_file("subframe_size", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_subframe_size);
+	debugfs_create_file("auto_ampdu[0:OFF,1:ON]", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    sc, &fops_auto_ampdu);
 	debugfs_create_file("regval", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
 			    sc, &fops_regval);
 	debugfs_create_bool("ignore_extcca", S_IRUSR | S_IWUSR,
@@ -1177,5 +1302,8 @@
 			   sc->debug.debugfs_phy, &sc->sc_ah->gpio_val);
 
 	sc->debug.regidx = 0;
+	sc->debug.auto_ampdu = 1;
+ 	sc->debug.ampdu_len = ATH_AMPDU_LIMIT_MAX;
+ 	sc->debug.retry_limit = 10;
 	return 0;
 }
 
diff -Naur a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
--- a/drivers/net/wireless/ath/ath9k/debug.h	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/debug.h	2011-06-02 19:55:33.332337000 +0100
@@ -179,6 +180,10 @@
 struct ath9k_debug {
 	struct dentry *debugfs_phy;
 	u32 regidx;
+	u32 ampdu_len;
+	u16 retry_limit;
+	u16 subframe_size;
+	u8 auto_ampdu;
 	struct ath_stats stats;
 };
 
diff -Naur a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
--- a/drivers/net/wireless/ath/ath9k/xmit.c	2011-05-27 20:04:49.000000000 +0100
+++ b/drivers/net/wireless/ath/ath9k/xmit.c	2011-06-02 19:58:19.647347000 +0100
@@ -616,8 +616,12 @@
 			if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
 				modeidx++;
 
-			frmlen = ath_max_4ms_framelen[modeidx][rates[i].idx];
-			max_4ms_framelen = min(max_4ms_framelen, frmlen);
+				frmlen = ath_max_4ms_framelen[modeidx][rates[i].idx];
+				
+			if (sc->debug.auto_ampdu==1) 
+				max_4ms_framelen = min(max_4ms_framelen, frmlen);
+			else 
+				max_4ms_framelen = sc->debug.ampdu_len;
 		}
 	}
 
@@ -641,7 +645,7 @@
 	 * The IE, however can hold up to 65536, which shows up here
 	 * as zero. Ignore 65536 since we  are constrained by hw.
 	 */
-	if (tid->an->maxampdu)
+	if (sc->debug.auto_ampdu==1 && tid->an->maxampdu)
 		aggr_limit = min(aggr_limit, tid->an->maxampdu);
 
 	return aggr_limit;

Re: [ath9k-devel] Patching ath9k/mac80211 to change MAC layer features

[Mohammed Shafi]

On Mon, Jun 27, 2011 at 11:07 PM, Fred Matthews <fredmm@hotmail.co.uk> wrote:
> Hi all,
>
> Much appreciated Mohammed Shafi, disabling aggregation works when
> replacing those lines with
>  sc->sc_flags &= ~SC_OP_TXAGGR;
>  sc->sc_flags &= ~SC_OP_RXAGGR;
> only issue is I must always recompile compat-wireless to
> re-enable/disable it again. I tried to port it using debugfs to be
> able to enable and disable at runtime but ath9k kept rebooting.

I am not sure we can enable/disable aggregation via debugfs, these
flags seem are set at initialization and based on this lot of things
happen in tx-path, initializing TID structure, ampdu action, rate
control  etc.

>
> Also I would be very grateful if someone can help regarding my
> attached patch and previous query:
>
> ------------
>  need to patch ath9k so that I can be able to modify/fix the A-MPDU
> aggregation frame length and other parameters such that they can be
> configured at runtime via debugfs. I made a newbie attempt at trying
> to change the aggregate length (attached), but I am unsure of the
> correctness/efficiency  - when applied throughput varies with
> different frame lengths entered but I can't be sure if its actually
> changing the aggregation length (passes the framelen/aggr_limit).
> Hence I would be very grateful if someone can assist in the correct
> way of doing this (possibly directly via mac80211).
>
>
> Also if the ampdu aggregate length is changed I believe the
> number/length of the subframes of the aggregate stays constant (at the
> default which is 32). I try to change this in my patch as well as the
> maximum software retries by just changing the default definition in
> ath9k.h, thus is there a (more) correct/better way of changing these.
> Finally, how can I patch the driver to be able to disable Block-Acks
> via debugfs or otherwise.
> ---------------
>
> Thank you very much
>
>
>
> On Mon, Jun 20, 2011 at 9:15 AM, Mohammed Shafi
> <shafi.wireless@gmail.com> wrote:
>> On Fri, Jun 17, 2011 at 2:09 AM, Fred Matthews <fredmm@hotmail.co.uk> wrote:
>>> Hello all,
>>>
>>>
>>> I have a query regarding patching ath9k/mac80211 to change MAC layer
>>> features and I would be most grateful if someone can assist.
>>>
>>>
>>> I need to patch ath9k so that I can be able to modify/fix the A-MPDU
>>> aggregation frame length and other parameters such that they can be
>>> configured at runtime via debugfs. I made a newbie attempt at trying to
>>> change the aggregate length (attached), but I am unsure of the
>>> correctness/efficiency  - when applied throughput varies with different
>>> frame lengths entered but I can't be sure if its actually changing the
>>> aggregation length (passes the framelen/aggr_limit). Hence I would be very
>>> grateful if someone can assist in the correct way of doing this (possibly
>>> directly via mac80211).
>>>
>>>
>>>
>>> Also if the ampdu aggregate length is changed I believe the number/length of
>>> the subframes of the aggregate stays constant (at the default which is
>>> 32). I try to change this in my patch as well as the maximum software
>>> retries by just changing the default definition in ath9k.h, thus is there a
>>> (more) correct/better way of changing these. Finally, how can I patch the
>>> driver to be able to disable Block-Acks/aggregation via debugfs or
>>> otherwise.
>>
>>
>> to disable aggregation in the driver, please try this
>> diff --git a/drivers/net/wireless/ath/ath9k/init.c
>> b/drivers/net/wireless/ath/ath9k/init.c
>> index d4b166c..e0175d0 100644
>> --- a/drivers/net/wireless/ath/ath9k/init.c
>> +++ b/drivers/net/wireless/ath/ath9k/init.c
>> @@ -524,8 +524,6 @@ static void ath9k_init_misc(struct ath_softc *sc)
>>        sc->config.txpowlimit = ATH_TXPOWER_MAX;
>>
>>        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT) {
>> -               sc->sc_flags |= SC_OP_TXAGGR;
>> -               sc->sc_flags |= SC_OP_RXAGGR;
>>        }
>>
>>        common->tx_chainmask = sc->sc_ah->caps.tx_chainmask;
>>
>> if you want only tx-aggregation to be disabled , please comment out only that.
>> also you can completely disable HT by
>> diff --git a/drivers/net/wireless/ath/ath9k/hw.c
>> b/drivers/net/wireless/ath/ath9k/hw.c
>> index 6de2655..696b4cc 100644
>> --- a/drivers/net/wireless/ath/ath9k/hw.c
>> +++ b/drivers/net/wireless/ath/ath9k/hw.c
>> @@ -1915,10 +1915,7 @@ int ath9k_hw_fill_cap_info(struct ath_hw *ah)
>>
>>        common->crypt_caps |= ATH_CRYPT_CAP_CIPHER_AESCCM;
>>
>> -       if (ah->hw_version.devid != AR2427_DEVID_PCIE)
>> -               pCap->hw_caps |= ATH9K_HW_CAP_HT;
>> -       else
>> -               pCap->hw_caps &= ~ATH9K_HW_CAP_HT;
>> +       pCap->hw_caps &= ~ATH9K_HW_CAP_HT;
>>
>>        if (AR_SREV_9271(ah))
>>                pCap->num_gpio_pins = AR9271_NUM_GPIO;
>>
>>
>>
>>
>>>
>>>
>>>
>>> I highly appreciate, help in any of the above, as well as other advice,
>>> Many thanks
>>>
>>> _______________________________________________
>>> ath9k-devel mailing list
>>> ath9k-devel@lists.ath9k.org
>>> https://lists.ath9k.org/mailman/listinfo/ath9k-devel
>>>
>>>
>>
>>
>>
>> --
>> shafi
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
>



-- 
shafi

Re: [ath9k-devel] Patching ath9k/mac80211 to change MAC layer features

[Daniel Smith]

On Tue, Jun 28, 2011 at 3:00 AM, Mohammed Shafi
<shafi.wireless@gmail.com> wrote:
> On Mon, Jun 27, 2011 at 11:07 PM, Fred Matthews <fredmm@hotmail.co.uk> wrote:
>> Hi all,
>>
>> Much appreciated Mohammed Shafi, disabling aggregation works when
>> replacing those lines with
>>  sc->sc_flags &= ~SC_OP_TXAGGR;
>>  sc->sc_flags &= ~SC_OP_RXAGGR;
>> only issue is I must always recompile compat-wireless to
>> re-enable/disable it again. I tried to port it using debugfs to be
>> able to enable and disable at runtime but ath9k kept rebooting.
>
> I am not sure we can enable/disable aggregation via debugfs, these
> flags seem are set at initialization and based on this lot of things
> happen in tx-path, initializing TID structure, ampdu action, rate
> control  etc.
>

The project I am on we have to deal with a situation where we change
the hardware environment and thus have to change some of the
initialization parameters. Obviously the environment is a little
unique, but I believe this should work for you. Before the changes are
made we do a

                if (sc->nvifs > 0) {
                        printk(KERN_INFO "ath9k:card has an open interface\n");
                        return -EBUSY;
                }

                pdev = to_pci_dev(sc->dev);
                pdev->driver->remove(pdev);

then we make our hardware change and  then do a

                pci_id = pci_match_id(pdev->driver->id_table, pdev);
                err = pdev->driver->probe(pdev, pci_id);

which gives us a re-initialized instance of ath_hw and ath_softc for the radio

Hope this helps!

V/r,
Daniel P. Smith