Hi Magnus,
On Tue, Mar 20, 2018 at 9:20 AM, Magnus Damm <magnus.damm@xxxxxxxxx> wrote:
> From: Magnus Damm <damm+renesas@xxxxxxxxxxxxx>
>
> Booting sh73a0 KZM9G results in the following on the console:
>
> [ 0.030000] renesas_intc_irqpin e6900000.interrupt-controller: driving 8 irqs
> [ 0.040000] random: crng init done
> [ 0.120000] irq 35: nobody cared (try booting with the "irqpoll" option)
> [ 0.120000] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.16.0-rc5 #4
> [ 0.120000] Hardware name: Generic SH73A0 (Flattened Device Tree)
> ...
> [ 0.120000] Disabling IRQ #35
> [ 0.120000] renesas_intc_irqpin e6900004.interrupt-controller: driving 8 irqs
Thanks for bringing this to my attention again. I always assumed it was one of
the IIO devices keeping an IRQ line asserted, but it turns out I was wrong...
> Judging by the friendly board documentation there is nothing hooked up to
> that IRQ line. I wish we had proper schematics and not a less detailed
> board manual.
Oh there is: PORT54/IRQ10/FSICCK is driven by the same 11.2896 MHz
oscillator (OSC4) as FSIACK.
> With this patch I've tried to extend the irqpin driver to mask all interrupts
> on boot but it does not seem to help. Perhaps the PFC hardware needs to be
> configured somehow. More effort is needed to solve this issue.
That pin is part of the HDMI interface, cfr. section 5.27.
I've tried the below, but it doesn't work, as the interrupt controller is probed
before the pfc (it has to, due to dependencies from pfc on irqpin[0-3]).
--- a/arch/arm/boot/dts/sh73a0-kzm9g.dts
+++ b/arch/arm/boot/dts/sh73a0-kzm9g.dts
@@ -331,6 +331,15 @@
};
&pfc {
+ pinctrl-0 = <&fsic_pins>;
+ pinctrl-names = "default";
+
+ fsic_pins: hdmi {
+ /* FSICCK is driven by OSC4, causing interrupt storm */
+ groups = "fsic_mclk_in";
+ function = "fsic";
+ };
+
i2c3_pins: i2c3 {
groups = "i2c3_1";
function = "i2c3";
So probably we need some early quirk in pfc-sh73a0.c, to configure the
pin as fsicck on kzm9g.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
