low tx power with mt76x0e driver

[sanitariu]

Hello, There is still a problem with low tx power using 5G driver mt76x0e. Here is the router information:

system type : MediaTek MT7628AN ver:1 eco:2 machine : TP-Link Archer C20 v5

iw phy

Wiphy phy1 wiphy index: 1 max # scan SSIDs: 4 max scan IEs length: 2247 bytes max # sched scan SSIDs: 0 max # match sets: 0 max # scan plans: 1 max scan plan interval: -1 max scan plan iterations: 0 Retry short limit: 7 Retry long limit: 4 Coverage class: 0 (up to 0m) Device supports AP-side u-APSD. Device supports T-DLS. Available Antennas: TX 0x1 RX 0x1 Configured Antennas: TX 0x1 RX 0x1 Supported interface modes:

• IBSS
• managed
• AP
• AP/VLAN
• monitor
• mesh point
• P2P-client
• P2P-GO Band 2: Capabilities: 0x17e HT20/HT40 SM Power Save disabled RX Greenfield RX HT20 SGI RX HT40 SGI RX STBC 1-stream Max AMSDU length: 3839 bytes No DSSS/CCK HT40 Maximum RX AMPDU length 65535 bytes (exponent: 0x003) Minimum RX AMPDU time spacing: No restriction (0x00) HT TX/RX MCS rate indexes supported: 0-7 VHT Capabilities (0x31800120): Max MPDU length: 3895 Supported Channel Width: neither 160 nor 80+80 short GI (80 MHz) RX antenna pattern consistency TX antenna pattern consistency VHT RX MCS set: 1 streams: MCS 0-9 2 streams: not supported 3 streams: not supported 4 streams: not supported 5 streams: not supported 6 streams: not supported 7 streams: not supported 8 streams: not supported VHT RX highest supported: 0 Mbps VHT TX MCS set: 1 streams: MCS 0-9 2 streams: not supported 3 streams: not supported 4 streams: not supported 5 streams: not supported 6 streams: not supported 7 streams: not supported 8 streams: not supported VHT TX highest supported: 0 Mbps Frequencies:
  • 5180 MHz [36] (14.0 dBm)
  • 5200 MHz [40] (14.0 dBm)
  • 5220 MHz [44] (13.0 dBm)
  • 5240 MHz [48] (13.0 dBm)
  • 5260 MHz [52] (12.0 dBm) (radar detection)
  • 5280 MHz [56] (12.0 dBm) (radar detection)
  • 5300 MHz [60] (12.0 dBm) (radar detection)
  • 5320 MHz [64] (12.0 dBm) (radar detection)
  • 5500 MHz [100] (disabled)
  • 5520 MHz [104] (disabled)
  • 5540 MHz [108] (disabled)
  • 5560 MHz [112] (disabled)
  • 5580 MHz [116] (disabled)
  • 5600 MHz [120] (disabled)
  • 5620 MHz [124] (disabled)
  • 5640 MHz [128] (disabled)
  • 5660 MHz [132] (disabled)
  • 5680 MHz [136] (disabled)
  • 5700 MHz [140] (disabled)
  • 5720 MHz [144] (disabled)
  • 5745 MHz [149] (16.0 dBm)
  • 5765 MHz [153] (16.0 dBm)
  • 5785 MHz [157] (16.0 dBm)
  • 5805 MHz [161] (16.0 dBm)
  • 5825 MHz [165] (16.0 dBm)
  • 5845 MHz [169] (disabled)
  • 5865 MHz [173] (disabled) valid interface combinations:

• { IBSS } <= 1, #{ managed, AP, mesh point, P2P-client, P2P-GO } <= 8,

     total <= 8, #channels <= 1, STA/AP BI must match, radar detect widths: { 20 MHz (no HT), 20 MHz, 40 MHz, 80 MHz }

5Gz wifi is using 14db (25mW) which is useless after 5 meters away from the router. Maybe driver is reading the power from wrong location ? I may supply rom/radio for that router if someone needs to.

2.4Gz is fine.

[dmsza]

I've observed a similar (but somewhat worse) behavior with TP-Link RE200v2. More details at https://forum.openwrt.org/t/port-to-tp-link-re200/50540/214