On 2012-07-25 8:42 PM, Nick Kossifidis wrote: > 2012/7/23 Thomas Huehn <thomas@xxxxxxxxxxxxxxxxxxxxxxx>: >> This patch reduces the per rate target power eeprom reads for >> AR5K_EEPROM_MODE_11A from 10 to 8, as there are only 8 valid >> power curve entries on the eeprom. The former 10 reads lead to >> wrong per rate power limits where rates above 24MBit could be >> amplified with to high distortion leading to bad performance. >> This was fix validated against the madwifi codebase and a new >> AR5K_EEPROM_N_5GHZ_RATE_CHAN 8 is defined. >> >> Signed-off-by: Thomas Huehn <thomas@xxxxxxxxxxxxxxxxxxxxxxx> >> --- >> madwifi cross validation check. Thx to Felix Fiethkau >> --- > > > Thanks for catching this but the bug is elsewhere: > > I've tried to document hw code as much as I can, eeprom stuff is still > missing and I'm sorry for that but here is what comments say on phy.c > @ DOC: Per-rate tx power setting, that should give you an idea of > what's happening... > > 3498 * Rate power table contains indices to PCDAC/PDADC table (0.5dB steps - > 3499 * x values) and is indexed as follows: > 3500 * rates[0] - rates[7] -> OFDM rates > 3501 * rates[8] - rates[14] -> CCK rates > 3502 * rates[15] -> XR rates (they all have the same power) > > So guess why the last 2 "invalid" power gain values have the same > power levels for all rates ? They are for XR mode (they've put it > there on the eeprom because XR mode also operates at 5GHz) and since > XR stuff is stripped off Madwifi (at least the public HAL) that's why > it only reads 8 of the piers. It's not just stripped in the public HAL. Every driver that I've looked at only reads 8 of the piers in the function that parses the EEPROM. - Felix -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
