[BPI-R64] OpenWRT kernel 5.4.40 running from eMMC

please send mail to 肖 xiaoqj@banana-pi.com

Hi, @svintuss
Would you please create a github repo for all patches and firmware bin. I can’t follow your approach. Thanks.

Sure, will do that soon. I just want to find out how to make OpenWRT patches from manually modified files. I don’t like a “compile - install - make changes - recompile again - replace modules on working system” approach.

I’ve got some progress here.

After several hours of load testing with iperf3 I found out that mt7615 makes system crash if TX power exceeds 21 dBm. That means that in ‘AU’ or ‘US’ regional domains one have to manually limit TX power to 21 dBm.

I don’t know yet whether it’s my unit’s or a general BPI-MT7615 board/driver problem.

I also have that problem. I got a solution from BPI. If you want use BPI-MT7615 module on BPI-R64 board, The R64 board must modify a resistance to provide more power to the pci-e slot.

Which slot (pcie0,cn25?), which resistant and to which value?

You’re right.

Thanks to the assistance of 肖 xiaoqj@banana-pi.com from @sinovoip I’ve managed to solve the TX power crash problem.

BPI-R64’s mPCIe slot current is limited to 1.5A (1.44A to be precise). When TX power of mt7615e board exceeds 22 dBm it starts to draw too much current and the whole system crashes.

This 1.5A limit is managed by SY6280 programmable switch. There are two solutions:

  1. Short circuit pins 1 and 5 and remove the current limit.
  2. Increase current limit by replacing R217 resistor to 3K one. This will give 2,27A current limit. The resistor is 0402 (1 mm x 0.5 mm)

I tried method 1, I can confirm that it works. Board is stable with 23 dBm TX power. Maybe the same procedure could be done to CN8 slot too.

UPD: There seems to be an issue with method 1: mt7615e goes up only after initial power on. If one reboots the board or presses reset button there comes up this message in kernel log:

[   12.231122] mt7615e 0000:01:00.0: Firmware is not ready for download

UPD2: Can confirm that method 2 works without issue. After changing R217 to 3KOhm the board is working fine on 23 dBm.

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Cn8 has additional problem with missing capacitors on tx-lines

Is there any new state using eeprom from file? In Mainline i see only mtd version (which conflicts with mt7622), and mtd in 5.4 is broken (at least in openwrt)

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/wireless/mediatek/mt76/eeprom.c

And also mt76 git