On 2021-12-18 07:02, Seth Forshee wrote:

On Sat, Oct 30, 2021 at 01:12:08AM +0900, Sungbo Eo wrote:

quoted

On 2021-10-28 03:06, Seth Forshee wrote:

quoted

On Sun, Oct 24, 2021 at 08:38:21PM +0900, Sungbo Eo wrote:

quoted

This patch is based on MSIT Public Notification 2020-113 ("Unlicensed Radio
Equipment Established Without Notice"), officially announced on 2021-01-06.

The PSD must not exceed 2.5 mW/MHz if the frequency range includes all or
part of 5230-5250 MHz and the bandwidth is equal to or less than 40 MHz.
This leads to the following:
* 5230-5250 @ 20 -> 17 dBm
* 5210-5250 @ 40 -> 20 dBm
Here the power limits for 80/160 MHz bandwidth are also lowered to 17 dBm,
as it's not possible to set different power limits for different bandwidths
at the moment.

Extend the last 5 GHz frequency range to 5850 MHz.

WiFi 6E is now allowed with the following restrictions:
* Indoor: the full 1.2 GHz range, up to 160 MHz bandwidth and 250mW EIRP
* Outdoor: the lower 500 MHz range, up to 160 MHz bandwidth and 25mW EIRP
Here only the former entry is added.

And also update the regulatory source links.

Signed-off-by: Sungbo Eo <redacted>
---
v2:
* split 5150-5250 MHz band rule to accommodate the PSD limit
* remove AUTO-BW flag from 6 GHz band rule
---
   db.txt | 17 ++++++++++++-----
   1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/db.txt b/db.txt
index 6e8dbef..387ac93 100644
--- a/db.txt
+++ b/db.txt

@@ -862,15 +862,22 @@ country KP: DFS-JP
   	(5490 - 5630 @ 20), (30), DFS
   	(5735 - 5815 @ 20), (30)
+# Source:
+# https://www.law.go.kr/LSW//admRulLsInfoP.do?chrClsCd=&admRulSeq=2100000196972
+# https://www.law.go.kr/LSW//admRulLsInfoP.do?chrClsCd=&admRulSeq=2100000196973
+# https://www.law.go.kr/LSW//admRulLsInfoP.do?chrClsCd=&admRulSeq=2100000196974
   country KR: DFS-JP
-	# ref: https://www.rra.go.kr
   	(2400 - 2483.5 @ 40), (23)
-	(5150 - 5250 @ 80), (23), AUTO-BW
+	(5150 - 5210 @ 40), (23), AUTO-BW
+	# max. PSD 2.5 mW/MHz in 5230-5250 MHz frequency range
+	(5210 - 5230 @ 20), (20), AUTO-BW
+	(5230 - 5250 @ 20), (17), AUTO-BW

Even with 5210-5230 split out like this, 5210-5250 @ 40 still gets
limited to 17 dBm by the 5230-5250 rule. So why do we need to split out
5210-5230 separate from 5150-5210?

I did some tests with regdb and I found out that the rule to be applied
depends on the main 20 MHz channel. With the rules above, if I select
channel 48 (5230-5250) and enable VHT40, then the TX power is set to 17 dBm.
OTOH if I select channel 44 (5210–5230) and enable VHT40, then the TX power
is set to 20 dBm. I'm not sure whether my result is really correct, though.

I'm sorry, when I saw the v3 patch I realized that I forgot to reply to
this email. I had wanted to take a look at the kernel source to try and
understand the behavior you described.

I took a quick look, and from what I'm seeing the minimum of the power
limits for the two ranges should be used. This is the behavior I expect.
Can you provide more detail about how you're getting that result?

Thanks,
Seth

I've got the result on MT7623+MT7615N AP with OpenWrt installed. (kernel 
5.10)
I set the channel and bandwidth in /etc/config/wireless (in 
OpenWrt-standard way) and checked the tx power with `iw dev wlan0 info` 
and Android WiFi Analyzer app.

# channel 48, htmode VHT40
type AP
channel 48 (5240 MHz), width: 40 MHz, center1: 5230 MHz
txpower 17.00 dBm

# channel 44, htmode VHT40
type AP
channel 44 (5220 MHz), width: 40 MHz, center1: 5230 MHz
txpower 20.00 dBm

The WiFi Analyzer app also reported higher RSSI for the channel 44 case.

I also had a quick look at net/wireless/reg.c and it seems you're right. 
Perhaps my tests were bad, I do believe your comments more than my 
result. ;)

Regards,
Sungbo