2009/10/28 Linus Torvalds <torva...@linux-foundation.org>: > > > On Sun, 25 Oct 2009, Gábor Stefanik wrote: >> >> Also, is there any reference to a failed channel switch in the log? > > I've been debugging this some more, and it looks like there are more > issues at play than just the DMA problem. > > With the b43 driver enabled, I seem to be unable to reliably suspend and > resume. Sometimes the machine just locks up hard, but sometimes I get > something like this on the resume path: > > b43-phy0 debug: Resuming... > b43-phy0 debug: Device resumed. > ... > b43-phy0: Loading firmware version 478.104 (2008-07-01 00:50:23) > b43-phy0 debug: b2062: Using crystal tab entry 19200 kHz. > b43-phy0 debug: RC calib: Failed to switch to channel 7, error = -5 > b43-phy0 debug: Chip initialized > b43-phy0 debug: PIO initialized > b43-phy0 debug: QoS disabled > b43-phy0 debug: Wireless interface started > b43-phy0 debug: Adding Interface type 2 > > and when that happens, it appears that then the _next_ suspend/resume > cycle will fail with a hard lockup. And sometimes the hard lockup happens > on the very first resume. > > But maybe that "Failed to switch to channel 7" error is entirely unrelated > to the "Locks up hard on resume" problem. But the lock-up seems to be tied > to the b43 driver too - the machine seems stable if I don't load that > module at all. > > What seems a bit odd is how the b43_lpphy_op_init() seems to try to switch > to channel 7 _twice_. It does: > > ... > lpphy_radio_init(dev); > lpphy_calibrate_rc(dev); > err = b43_lpphy_op_switch_channel(dev, 7); > ... > > and that lpphy_calibrate_rc() call will already have done the channel > switch for the lpphy_rev0_1_rc_calib() case. Maybe it should just switch > to channel 7 unconditionally before doing the lpphy_calibrate_rc()?
What we do is exactly what the spec calls for - specifically, rev.2+ cards don't switch to channel 7 during RC calibration, while rev.0/1 SoCs can have an NVRAM variable specifying a predetermined RC-Cap value, in which case the actual RC calibration doesn't even run (though the latter is not yet implemented). However, just switching to channel 7 at the beginning looks saner - Larry, what do you think about it? > > I dunno. I don't know the code, I don't know the hardware, the above is > just a random musing based on looking at the code around that warning > case. > > Linus > -- Vista: [V]iruses, [I]ntruders, [S]pyware, [T]rojans and [A]dware. :-) _______________________________________________ Bcm43xx-dev mailing list Bcm43xx-dev@lists.berlios.de https://lists.berlios.de/mailman/listinfo/bcm43xx-dev
