[RFC V2 0/8] nl80211: add 6GHz band support

[RFC V2 0/8] nl80211: add 6GHz band support

[Arend van Spriel]

This is more or less a resend. The difference with the previous RFC is
in the nl80211 API as the previous RFC was breaking ABI.

In 802.11ax D4.0 a new band has been proposed. This series contains
changes to cfg80211 for supporting this band. With 2GHz and 5GHz there
was no overlap in channel number. However, this new band has channel
numbers with a range from 1 up to 253. The only place I could find an
issue with this is in cfg80211_wext_freq(). Not sure how to deal with
that so it is not part of this series.

The series applies to the master branch of the mac80211-next repository.

Arend van Spriel (8):
  nl80211: add 6GHz band definition to enum nl80211_band
  cfg80211: add 6GHz UNII band definitions
  cfg80211: util: add 6GHz channel to freq conversion and vice versa
  cfg80211: extend ieee80211_operating_class_to_band() for 6GHz
  cfg80211: add 6GHz in code handling array with NUM_NL80211_BANDS
    entries
  cfg80211: use same IR permissive rules for 6GHz band
  cfg80211: ibss: use 11a mandatory rates for 6GHz band operation
  cfg80211: apply same mandatory rate flags for 5GHz and 6GHz

 include/uapi/linux/nl80211.h |  2 ++
 net/wireless/chan.c          |  3 ++-
 net/wireless/ibss.c          | 16 +++++++++++-----
 net/wireless/nl80211.c       |  1 +
 net/wireless/reg.c           | 21 +++++++++++++++++++--
 net/wireless/trace.h         |  3 ++-
 net/wireless/util.c          | 14 +++++++++++++-
 7 files changed, 50 insertions(+), 10 deletions(-)

-- 
1.9.1

[RFC V2 1/8] nl80211: add 6GHz band definition to enum nl80211_band

[Arend van Spriel]

In the 802.11ax specification a new band is introduced, which
is also proposed by FCC for unlicensed use. This band is referred
to as 6GHz spanning frequency range from 5925 to 7125 MHz.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
changes:
  - V2
	fix ABI breakage by appending the new band definition.
---
 include/uapi/linux/nl80211.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 8fc3a43..45b9117 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -4536,6 +4536,7 @@ enum nl80211_txrate_gi {
  * @NL80211_BAND_2GHZ: 2.4 GHz ISM band
  * @NL80211_BAND_5GHZ: around 5 GHz band (4.9 - 5.7 GHz)
  * @NL80211_BAND_60GHZ: around 60 GHz band (58.32 - 69.12 GHz)
+ * @NL80211_BAND_6GHZ: around 6 GHz band (5.9 - 7.2 GHz)
  * @NUM_NL80211_BANDS: number of bands, avoid using this in userspace
  *	since newer kernel versions may support more bands
  */
@@ -4543,6 +4544,7 @@ enum nl80211_band {
 	NL80211_BAND_2GHZ,
 	NL80211_BAND_5GHZ,
 	NL80211_BAND_60GHZ,
+	NL80211_BAND_6GHZ,
 
 	NUM_NL80211_BANDS,
 };
-- 
1.9.1

[RFC V2 2/8] cfg80211: add 6GHz UNII band definitions

[Arend van Spriel]

For the new 6GHz there are new UNII band definitions as listed
in the FCC notice [1].

[1] https://docs.fcc.gov/public/attachments/FCC-18-147A1_Rcd.pdf

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 net/wireless/reg.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 4831ad74..646107a 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -3806,8 +3806,9 @@ void wiphy_regulatory_deregister(struct wiphy *wiphy)
 }
 
 /*
- * See http://www.fcc.gov/document/5-ghz-unlicensed-spectrum-unii, for
- * UNII band definitions
+ * See FCC notices for UNII band definitions
+ *  5GHz: https://www.fcc.gov/document/5-ghz-unlicensed-spectrum-unii
+ *  6GHz: https://www.fcc.gov/document/fcc-proposes-more-spectrum-unlicensed-use-0
  */
 int cfg80211_get_unii(int freq)
 {
@@ -3831,6 +3832,22 @@ int cfg80211_get_unii(int freq)
 	if (freq > 5725 && freq <= 5825)
 		return 4;
 
+	/* UNII-5 */
+	if (freq > 5925 && freq <= 6425)
+		return 5;
+
+	/* UNII-6 */
+	if (freq > 6425 && freq <= 6525)
+		return 6;
+
+	/* UNII-7 */
+	if (freq > 6525 && freq <= 6875)
+		return 7;
+
+	/* UNII-8 */
+	if (freq > 6875 && freq <= 7125)
+		return 8;
+
 	return -EINVAL;
 }
 
-- 
1.9.1

[RFC V2 3/8] cfg80211: util: add 6GHz channel to freq conversion and vice versa

[Arend van Spriel]

Extend the functions ieee80211_channel_to_frequency() and
ieee80211_frequency_to_channel() to support 6GHz band according
specification in 802.11ax D4.1 27.3.22.2.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 net/wireless/util.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 1c39d6a..4e633d4 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -91,6 +91,11 @@ int ieee80211_channel_to_frequency(int chan, enum nl80211_band band)
 		else
 			return 5000 + chan * 5;
 		break;
+	case NL80211_BAND_6GHZ:
+		/* see 802.11ax D4.1 27.3.22.2 */
+		if (chan <= 253)
+			return 5940 + chan * 5;
+		break;
 	case NL80211_BAND_60GHZ:
 		if (chan < 7)
 			return 56160 + chan * 2160;
@@ -111,8 +116,11 @@ int ieee80211_frequency_to_channel(int freq)
 		return (freq - 2407) / 5;
 	else if (freq >= 4910 && freq <= 4980)
 		return (freq - 4000) / 5;
-	else if (freq <= 45000) /* DMG band lower limit */
+	else if (freq < 5940)
 		return (freq - 5000) / 5;
+	else if (freq <= 45000) /* DMG band lower limit */
+		/* see 802.11ax D4.1 27.3.22.2 */
+		return (freq - 5940) / 5;
 	else if (freq >= 58320 && freq <= 70200)
 		return (freq - 56160) / 2160;
 	else
-- 
1.9.1

[RFC V2 4/8] cfg80211: extend ieee80211_operating_class_to_band() for 6GHz

[Arend van Spriel]

Add 6GHz operating class range as defined in 802.11ax D4.1 Annex E.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 net/wireless/util.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 4e633d4..4462837 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1474,6 +1474,9 @@ bool ieee80211_operating_class_to_band(u8 operating_class,
 	case 128 ... 130:
 		*band = NL80211_BAND_5GHZ;
 		return true;
+	case 131 ... 135:
+		*band = NL80211_BAND_6GHZ;
+		return true;
 	case 81:
 	case 82:
 	case 83:
-- 
1.9.1

[RFC V2 5/8] cfg80211: add 6GHz in code handling array with NUM_NL80211_BANDS entries

[Arend van Spriel]

In nl80211.c there is a policy for all bands in NUM_NL80211_BANDS and
in trace.h there is a callback trace for multicast rates which is per
band in NUM_NL80211_BANDS. Both need to be extended for the new
NL80211_BAND_6GHZ.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 net/wireless/nl80211.c | 1 +
 net/wireless/trace.h   | 3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index fc83dd1..57bc35a 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -667,6 +667,7 @@ static int validate_ie_attr(const struct nlattr *attr,
 nl80211_match_band_rssi_policy[NUM_NL80211_BANDS] = {
 	[NL80211_BAND_2GHZ] = { .type = NLA_S32 },
 	[NL80211_BAND_5GHZ] = { .type = NLA_S32 },
+	[NL80211_BAND_6GHZ] = { .type = NLA_S32 },
 	[NL80211_BAND_60GHZ] = { .type = NLA_S32 },
 };
 
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 4fbb91a..d98ad2b 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -2446,10 +2446,11 @@
 		       sizeof(int) * NUM_NL80211_BANDS);
 	),
 	TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", "
-		  "mcast_rates [2.4GHz=0x%x, 5.2GHz=0x%x, 60GHz=0x%x]",
+		  "mcast_rates [2.4GHz=0x%x, 5.2GHz=0x%x, 6GHz=0x%x, 60GHz=0x%x]",
 		  WIPHY_PR_ARG, NETDEV_PR_ARG,
 		  __entry->mcast_rate[NL80211_BAND_2GHZ],
 		  __entry->mcast_rate[NL80211_BAND_5GHZ],
+		  __entry->mcast_rate[NL80211_BAND_6GHZ],
 		  __entry->mcast_rate[NL80211_BAND_60GHZ])
 );
 
-- 
1.9.1

[RFC V2 6/8] cfg80211: use same IR permissive rules for 6GHz band

[Arend van Spriel]

The function cfg80211_ir_permissive_chan() is applicable for
6GHz band as well so make sure it is handled.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 net/wireless/chan.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 7dc1bbd..7c9d204 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -894,7 +894,8 @@ static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
 		if (chan == other_chan)
 			return true;
 
-		if (chan->band != NL80211_BAND_5GHZ)
+		if (chan->band != NL80211_BAND_5GHZ &&
+		    chan->band != NL80211_BAND_6GHZ)
 			continue;
 
 		r1 = cfg80211_get_unii(chan->center_freq);
-- 
1.9.1

[RFC V2 7/8] cfg80211: ibss: use 11a mandatory rates for 6GHz band operation

[Arend van Spriel]

The default mandatory rates, ie. when not specified by user-space, is
determined by the band. Select 11a rateset for 6GHz band.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 net/wireless/ibss.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/net/wireless/ibss.c b/net/wireless/ibss.c
index d1743e6..ae8fe66 100644
--- a/net/wireless/ibss.c
+++ b/net/wireless/ibss.c
@@ -104,13 +104,19 @@ int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 		* use the mandatory rate set for 11b or
 		* 11a for maximum compatibility.
 		*/
-		struct ieee80211_supported_band *sband =
-			rdev->wiphy.bands[params->chandef.chan->band];
+		struct ieee80211_supported_band *sband;
+		enum nl80211_band band;
+		u32 flag;
 		int j;
-		u32 flag = params->chandef.chan->band == NL80211_BAND_5GHZ ?
-			IEEE80211_RATE_MANDATORY_A :
-			IEEE80211_RATE_MANDATORY_B;
 
+		band = params->chandef.chan->band;
+		if (band == NL80211_BAND_5GHZ ||
+		    band == NL80211_BAND_6GHZ)
+			flag = IEEE80211_RATE_MANDATORY_A;
+		else
+			flag = IEEE80211_RATE_MANDATORY_B;
+
+		sband = rdev->wiphy.bands[band];
 		for (j = 0; j < sband->n_bitrates; j++) {
 			if (sband->bitrates[j].flags & flag)
 				params->basic_rates |= BIT(j);
-- 
1.9.1

[RFC V2 8/8] cfg80211: apply same mandatory rate flags for 5GHz and 6GHz

[Arend van Spriel]

For the new 6GHz band the same rules apply for mandatory rates so
add it to set_mandatory_flags_band() function.

Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Leon Zegers <leon.zegers@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 net/wireless/util.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 4462837..f0558e7 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -156,6 +156,7 @@ static void set_mandatory_flags_band(struct ieee80211_supported_band *sband)
 
 	switch (sband->band) {
 	case NL80211_BAND_5GHZ:
+	case NL80211_BAND_6GHZ:
 		want = 3;
 		for (i = 0; i < sband->n_bitrates; i++) {
 			if (sband->bitrates[i].bitrate == 60 ||
-- 
1.9.1

Re: [RFC V2 5/8] cfg80211: add 6GHz in code handling array with NUM_NL80211_BANDS entries

[Johannes Berg]

On Tue, 2019-06-25 at 13:10 +0200, Arend van Spriel wrote:
> 
> +++ b/net/wireless/trace.h
> @@ -2446,10 +2446,11 @@
>  		       sizeof(int) * NUM_NL80211_BANDS);
>  	),
>  	TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", "
> -		  "mcast_rates [2.4GHz=0x%x, 5.2GHz=0x%x, 60GHz=0x%x]",
> +		  "mcast_rates [2.4GHz=0x%x, 5.2GHz=0x%x, 6GHz=0x%x, 60GHz=0x%x]",
>  		  WIPHY_PR_ARG, NETDEV_PR_ARG,
>  		  __entry->mcast_rate[NL80211_BAND_2GHZ],
>  		  __entry->mcast_rate[NL80211_BAND_5GHZ],
> +		  __entry->mcast_rate[NL80211_BAND_6GHZ],
>  		  __entry->mcast_rate[NL80211_BAND_60GHZ])
>  );

This doesn't really - you just pointed out that legacy rates aren't
permitted, and so this bitmap doesn't make sense for 6 GHz?

johannes

Re: [RFC V2 7/8] cfg80211: ibss: use 11a mandatory rates for 6GHz band operation

[Johannes Berg]

On Tue, 2019-06-25 at 13:10 +0200, Arend van Spriel wrote:
> The default mandatory rates, ie. when not specified by user-space, is
> determined by the band. Select 11a rateset for 6GHz band.

Hmm. Again, didn't you just say that 6 GHz didn't allow legacy rates,
and so these shouldn't be mandatory?

johannes

Re: [RFC V2 7/8] cfg80211: ibss: use 11a mandatory rates for 6GHz band operation

[Igor Mitsyanko]

On 6/28/19 6:04 AM, Johannes Berg wrote:
>> The default mandatory rates, ie. when not specified by user-space, is
>> determined by the band. Select 11a rateset for 6GHz band.
> Hmm. Again, didn't you just say that 6 GHz didn't allow legacy rates,
> and so these shouldn't be mandatory?
> 
> johannes
> 

I believe 6GHz allows only HE and non-HT rates (for beacons etc).

Re: [RFC V2 0/8] nl80211: add 6GHz band support

[Johannes Berg]

Hi Arend,

After all the discussion, I think we want this? Care to resend?

I think I want it at least because we shouldn't advertise HT/VHT on 6
GHz as is (just as part of HE) and that's easier if we have a different
band enum, for the capability storage...

> The only place I could find an
> issue with this is in cfg80211_wext_freq(). Not sure how to deal with
> that so it is not part of this series.

Just finally break wext and say if you want to use 6 GHz you need to use
nl80211? :)

johannes

Re: [RFC V2 0/8] nl80211: add 6GHz band support

[Arend Van Spriel]

On July 24, 2019 11:35:14 AM Johannes Berg <johannes@sipsolutions.net> wrote:

> Hi Arend,
>
>
>
>
> After all the discussion, I think we want this?

I think so yes. Even if it is just informational for user-space it seems to 
make sense for kernel side.

> Care to resend?

Will do.

> I think I want it at least because we shouldn't advertise HT/VHT on 6
> GHz as is (just as part of HE) and that's easier if we have a different
> band enum, for the capability storage...

Right.

>
>> The only place I could find an
>> issue with this is in cfg80211_wext_freq(). Not sure how to deal with
>> that so it is not part of this series.
>
> Just finally break wext and say if you want to use 6 GHz you need to use
> nl80211? :)

Probably is true for he support as well. Not sure. Have not been using wext 
for the last decade ;-)

Regards,
Arend

Re: [RFC V2 0/8] nl80211: add 6GHz band support

[Johannes Berg]

On Wed, 2019-07-24 at 15:40 +0200, Arend Van Spriel wrote:
> 
> > > The only place I could find an
> > > issue with this is in cfg80211_wext_freq(). Not sure how to deal with
> > > that so it is not part of this series.
> > 
> > Just finally break wext and say if you want to use 6 GHz you need to use
> > nl80211? :)
> 
> Probably is true for he support as well. Not sure. Have not been using wext 
> for the last decade ;-)

Me neither, our official releases don't even support it.

Btw, there's a compiler warning introduced by the first patch, I think
the fix is trivial though to add the 6GHZ in one place in mac80211
already.

johannes