On 04/06/2016 04:11 PM, Sjoerd Simons wrote:
Thanks for you feedback, it put me on the right track.
[...]
I've got a Porter board (Revision B) which stopped showing serial
output since the patch mentioned in the subject. The terrible
clearly
wrong hack below gets serial back (reverting to just the fck clock
for
scif0) on both linux-next and linux master.
Thanks for your report!
I assume something is wrong with the SCIF_CLK input.
Hence I guess the issue is also fixed by removing the "&scif_clk"
block in
arch/arm/boot/dts/r8a7791-porter.dts?
Confusingly it didn't, see the patch i just sent out:
ARM: dts: r8a7791: Don't disable referenced optional clocks
That patch looks, er... strange/incomplete. Perhaps we should fix
clk_get() instead?
Unfortunately I don't have enough documentation on the
board/hardware
to diagnose this further, but hopefully someone else does ;)
I don't have a Porter, so I based my patch on the documentation,
which states:
The SCIF_CLK pin of the R-CarM2 is connected to the crystal
oscillator
(X4) on the R-Car M2 Application Development Board, which
supplies a clock frequency of 14.7456 MHz.
which matches r8a7791-porter.dts, if I'm not mistaken.
Perhaps the documentation applies to another version of the board
than
Revision B?
Judging from:
http://elinux.org/File:R-CarM2-KOELSCH_PORTER-B_PORTER_C_Comparison.pdf
That's a kind of document I needed all the time, thanks! :-)
that oscillator is not mounted on porter B & C. Just sent out a revert
for your patch that add this. The combination of both patches got me my
serial back without weird hacks \o/
I've never seen the revert posted...
MBR, Sergei
