The 6GHz band does not have regulatory approval yet, but things are
moving forward. However, that has led to a change in the channelization
of the 6GHz band which has been accepted in the 11ax specification. It
also fixes a missing MHZ_TO_KHZ() macro for 6GHz channels while at it.
This change is primarily thrown in to discuss how to deal with it.
I noticed ath11k adding 6G support with old channelization and ditto
for iw. It probably involves changes in hostapd as well.
Cc: Pradeep Kumar Chitrapu <[email protected]>
Cc: Jouni Malinen <[email protected]>
Signed-off-by: Arend van Spriel <[email protected]>
---
V2:
- deal with channel 2 in ieee80211_chandef_to_operating_class()
---
net/wireless/util.c | 49 ++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 44 insertions(+), 5 deletions(-)
diff --git a/net/wireless/util.c b/net/wireless/util.c
index df75e58eca5d..220f44ae3a70 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -92,9 +92,11 @@ u32 ieee80211_channel_to_freq_khz(int chan, enum
nl80211_band band)
return MHZ_TO_KHZ(5000 + chan * 5);
break;
case NL80211_BAND_6GHZ:
- /* see 802.11ax D4.1 27.3.22.2 */
+ /* see 802.11ax D6.1 27.3.23.2 */
+ if (chan == 2)
+ return MHZ_TO_KHZ(5935);
if (chan <= 253)
- return 5940 + chan * 5;
+ return MHZ_TO_KHZ(5950 + chan * 5);
break;
case NL80211_BAND_60GHZ:
if (chan < 7)
@@ -119,11 +121,14 @@ int ieee80211_freq_khz_to_channel(u32 freq)
return (freq - 2407) / 5;
else if (freq >= 4910 && freq <= 4980)
return (freq - 4000) / 5;
- else if (freq < 5945)
+ else if (freq < 5935)
return (freq - 5000) / 5;
+ else if (freq == 5935)
+ /* see 802.11ax D6.1 27.3.23.2 */
+ return 2;
else if (freq <= 45000) /* DMG band lower limit */
- /* see 802.11ax D4.1 27.3.22.2 */
- return (freq - 5940) / 5;
+ /* see 802.11ax D6.1 27.3.23.2 */
+ return (freq - 5950) / 5;
else if (freq >= 58320 && freq <= 70200)
return (freq - 56160) / 2160;
else
@@ -1662,6 +1667,40 @@ bool ieee80211_chandef_to_operating_class(struct
cfg80211_chan_def *chandef,
return true;
}
+ /* 6GHz, channels 1..233 */
+ if (freq == 5935) {
+ if (chandef->width != NL80211_CHAN_WIDTH_20)
+ return false;
+
+ *op_class = 136;
+ return true;
+ } else if (freq > 5935 && freq <= 7115) {
+ switch (chandef->width) {
+ case NL80211_CHAN_WIDTH_20:
+ *op_class = 131;
+ break;
+ case NL80211_CHAN_WIDTH_40:
+ *op_class = 132;
+ break;
+ case NL80211_CHAN_WIDTH_80:
+ *op_class = 133;
+ break;
+ case NL80211_CHAN_WIDTH_160:
+ *op_class = 134;
+ break;
+ case NL80211_CHAN_WIDTH_80P80:
+ *op_class = 135;
+ break;
+ case NL80211_CHAN_WIDTH_5:
+ case NL80211_CHAN_WIDTH_10:
+ case NL80211_CHAN_WIDTH_20_NOHT:
+ default:
+ return false;
+ }
+
+ return true;
+ }
+
/* 56.16 GHz, channel 1..4 */
if (freq >= 56160 + 2160 * 1 && freq <= 56160 + 2160 * 6) {
if (chandef->width >= NL80211_CHAN_WIDTH_40)
--
2.18.0
On Fri, 2020-05-29 at 11:41 +0200, Arend Van Spriel wrote:
> It also fixes a missing MHZ_TO_KHZ() macro for 6GHz channels while at it.
Yeah, I actually saw and fixed that earlier, but whatever. I can fix up
any issues.
> case NL80211_BAND_6GHZ:
> - /* see 802.11ax D4.1 27.3.22.2 */
> + /* see 802.11ax D6.1 27.3.23.2 */
> + if (chan == 2)
> + return MHZ_TO_KHZ(5935);
> if (chan <= 253)
> - return 5940 + chan * 5;
> + return MHZ_TO_KHZ(5950 + chan * 5);
So this can return 5950+5*253 == 7215
> @@ -119,11 +121,14 @@ int ieee80211_freq_khz_to_channel(u32 freq)
> else if (freq <= 45000) /* DMG band lower limit */
> - /* see 802.11ax D4.1 27.3.22.2 */
> - return (freq - 5940) / 5;
> + /* see 802.11ax D6.1 27.3.23.2 */
> + return (freq - 5950) / 5;
and here you have no real upper bound, which is fine
> @@ -1662,6 +1667,40 @@ bool ieee80211_chandef_to_operating_class(struct
> + /* 6GHz, channels 1..233 */
> + if (freq == 5935) {
> + if (chandef->width != NL80211_CHAN_WIDTH_20)
> + return false;
> +
> + *op_class = 136;
> + return true;
> + } else if (freq > 5935 && freq <= 7115) {
but here both the comment and the code say 7115? Should that be 1..253
and 7215, respectively?
I can fix, no need to resend.
johannes
On May 29, 2020 11:53:30 AM Johannes Berg <[email protected]> wrote:
> On Fri, 2020-05-29 at 11:41 +0200, Arend Van Spriel wrote:
>> It also fixes a missing MHZ_TO_KHZ() macro for 6GHz channels while at it.
>
> Yeah, I actually saw and fixed that earlier, but whatever. I can fix up
> any issues.
>
>> case NL80211_BAND_6GHZ:
>> - /* see 802.11ax D4.1 27.3.22.2 */
>> + /* see 802.11ax D6.1 27.3.23.2 */
>> + if (chan == 2)
>> + return MHZ_TO_KHZ(5935);
>> if (chan <= 253)
>> - return 5940 + chan * 5;
>> + return MHZ_TO_KHZ(5950 + chan * 5);
>
> So this can return 5950+5*253 == 7215
>
>> @@ -119,11 +121,14 @@ int ieee80211_freq_khz_to_channel(u32 freq)
>
>> else if (freq <= 45000) /* DMG band lower limit */
>> - /* see 802.11ax D4.1 27.3.22.2 */
>> - return (freq - 5940) / 5;
>> + /* see 802.11ax D6.1 27.3.23.2 */
>> + return (freq - 5950) / 5;
>
> and here you have no real upper bound, which is fine
>
>> @@ -1662,6 +1667,40 @@ bool ieee80211_chandef_to_operating_class(struct
>
>> + /* 6GHz, channels 1..233 */
>> + if (freq == 5935) {
>> + if (chandef->width != NL80211_CHAN_WIDTH_20)
>> + return false;
>> +
>> + *op_class = 136;
>> + return true;
>> + } else if (freq > 5935 && freq <= 7115) {
>
> but here both the comment and the code say 7115? Should that be 1..253
> and 7215, respectively?
>
> I can fix, no need to resend.
The 802.11 spec specifies the 1..253 range. The FCC has proposed the U-NII
bands 5 to 8 for the 6G band. U-NII-8 ends at 7125 so the highest 20MHz
center freq is 7115, ie. channel 233. Have to admit that mixing the two in
this patch can be confusing. I leave it at your discretion how to fix it. I
can also resend if necessary.
Regards,
Arend