Armadillo800EVA legacy defconfig seems busted on my board

Armadillo800EVA legacy defconfig seems busted on my board

[Magnus Damm]

Hi everyone,

On my r8a7740 Armadillo board I've been playing with multiplatform and
CCF recently. While doing that I noticed that the defconfig doesn't
seem to work.

Maybe this is just my board - the boot loader seems unstable in
general and my entire setup requires an additional switch for the
Ethernet PHY to even get link up - autonegotiation seems busted with
the boot loader...

Anyway, if I try to boot the zImage generated from
armadillo800eva_defconfig I get zero console output. I managed to
track it down to the FB bits being busted.

If this is happening on other boards as well then perhaps we shall
adjust the defconfig? Or even better - fix the LCDC driver or whatever
is keeping the board from booting.

Good news is that DT reference seems fine. =)

Cheers,

/ magnus

Re: Armadillo800EVA legacy defconfig seems busted on my board

[Geert Uytterhoeven]

Hi Magnus,

On Fri, Aug 8, 2014 at 1:26 PM, Magnus Damm <magnus.damm@gmail.com> wrote:
> On my r8a7740 Armadillo board I've been playing with multiplatform and
> CCF recently. While doing that I noticed that the defconfig doesn't
> seem to work.
>
> Maybe this is just my board - the boot loader seems unstable in

When starting the kernel, it indeed sometimes hangs after

        Doing init=/init

Usually this happens after cold boot, so remote controlled power switches
don't help here.

> general and my entire setup requires an additional switch for the
> Ethernet PHY to even get link up - autonegotiation seems busted with
> the boot loader...

Working fine here with both a 100 Mbps or a Gbps switch.
Gether is supposed to be gigabit, but I only get 100 Mbps.
Ethtool tells me only 10 or 100 Mbps are available?

What kind of switch do you need? What doesn't work?

> Anyway, if I try to boot the zImage generated from
> armadillo800eva_defconfig I get zero console output. I managed to
> track it down to the FB bits being busted.

Strange, armadillo800eva_defconfig is working fine for me on
renesas-devel-v3.16-20140808, after I added the appropriate nfsrootkernel command line parameter.

> If this is happening on other boards as well then perhaps we shall
> adjust the defconfig? Or even better - fix the LCDC driver or whatever
> is keeping the board from booting.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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

Re: Armadillo800EVA legacy defconfig seems busted on my board

[Simon Horman]

On Fri, Aug 08, 2014 at 03:02:27PM +0200, Geert Uytterhoeven wrote:
> Hi Magnus,
> 
> On Fri, Aug 8, 2014 at 1:26 PM, Magnus Damm <magnus.damm@gmail.com> wrote:
> > On my r8a7740 Armadillo board I've been playing with multiplatform and
> > CCF recently. While doing that I noticed that the defconfig doesn't
> > seem to work.
> >
> > Maybe this is just my board - the boot loader seems unstable in
> 
> When starting the kernel, it indeed sometimes hangs after
> 
>         Doing init=/init
> 
> Usually this happens after cold boot, so remote controlled power switches
> don't help here.
> 
> > general and my entire setup requires an additional switch for the
> > Ethernet PHY to even get link up - autonegotiation seems busted with
> > the boot loader...
> 
> Working fine here with both a 100 Mbps or a Gbps switch.
> Gether is supposed to be gigabit, but I only get 100 Mbps.
> Ethtool tells me only 10 or 100 Mbps are available?
> 
> What kind of switch do you need? What doesn't work?
> 
> > Anyway, if I try to boot the zImage generated from
> > armadillo800eva_defconfig I get zero console output. I managed to
> > track it down to the FB bits being busted.
> 
> Strange, armadillo800eva_defconfig is working fine for me on
> renesas-devel-v3.16-20140808, after I added the appropriate nfsroot> kernel command line parameter.

It works for me too.

> 
> > If this is happening on other boards as well then perhaps we shall
> > adjust the defconfig? Or even better - fix the LCDC driver or whatever
> > is keeping the board from booting.

Re: Armadillo800EVA legacy defconfig seems busted on my board

[Magnus Damm]

Hi Geert,

On Fri, Aug 8, 2014 at 10:02 PM, Geert Uytterhoeven
<geert@linux-m68k.org> wrote:
> Hi Magnus,
>
> On Fri, Aug 8, 2014 at 1:26 PM, Magnus Damm <magnus.damm@gmail.com> wrote:
>> On my r8a7740 Armadillo board I've been playing with multiplatform and
>> CCF recently. While doing that I noticed that the defconfig doesn't
>> seem to work.
>>
>> Maybe this is just my board - the boot loader seems unstable in
>
> When starting the kernel, it indeed sometimes hangs after
>
>         Doing init=/init
>
> Usually this happens after cold boot, so remote controlled power switches
> don't help here.

Hm, I wonder what is causing these issues... INTC? =)

>> general and my entire setup requires an additional switch for the
>> Ethernet PHY to even get link up - autonegotiation seems busted with
>> the boot loader...
>
> Working fine here with both a 100 Mbps or a Gbps switch.
> Gether is supposed to be gigabit, but I only get 100 Mbps.
> Ethtool tells me only 10 or 100 Mbps are available?
>
> What kind of switch do you need? What doesn't work?

A shitty semi-managed Netgear Gigabit switch in Autonegotiation does
not work, however switching to a different unmanaged Netgear Gigabit
switch makes it work. So now i have a 5-port Gigabit switch hooked up
in between.

I suspect it to be some issue related to PHY settings in the boot loader.

>> Anyway, if I try to boot the zImage generated from
>> armadillo800eva_defconfig I get zero console output. I managed to
>> track it down to the FB bits being busted.
>
> Strange, armadillo800eva_defconfig is working fine for me on
> renesas-devel-v3.16-20140808, after I added the appropriate nfsroot> kernel command line parameter.

Odd. In my case I could not even get serial console output.

Thanks for your help!

Cheers,

/ magnus

Re: Armadillo800EVA legacy defconfig seems busted on my board

[Geert Uytterhoeven]

Hi Magnus,

On Tue, Aug 26, 2014 at 1:00 PM, Magnus Damm <magnus.damm@gmail.com> wrote:
> On Fri, Aug 8, 2014 at 10:02 PM, Geert Uytterhoeven
> <geert@linux-m68k.org> wrote:
>> On Fri, Aug 8, 2014 at 1:26 PM, Magnus Damm <magnus.damm@gmail.com> wrote:
>>> On my r8a7740 Armadillo board I've been playing with multiplatform and
>>> CCF recently. While doing that I noticed that the defconfig doesn't
>>> seem to work.
>>>
>>> Maybe this is just my board - the boot loader seems unstable in
>>
>> When starting the kernel, it indeed sometimes hangs after
>>
>>         Doing init=/init

Which is the last line printed by the Hermit bootloader.

>> Usually this happens after cold boot, so remote controlled power switches
>> don't help here.
>
> Hm, I wonder what is causing these issues... INTC? =)

I accidentally found a way to reproduce this. I'm not 100% sure it's the same
cause, but the symptoms look the same.

If power domain D4 (Coresight-ETM) is powered down, the kernel crashes
when suspending from s2ram with:

    Internal error: Oops - undefined instruction: 0 [#1] ARM

dbg_cpu_pm_notify() calls reset_ctrl_regs(), which crashes as D4 is powered
down, and commit 0d352e3d006c9589 ("ARM: hw_breakpoint: trap undef
instruction exceptions in reset_ctrl_regs") doesn't seem to work...

Ater that, pressing the reset switch and booting a Linux kernel gives the
same symptoms as on cold boot.
Pressing the reset switch again and booting a Linux kernel works.

I tried dumping printk() output to RAM and inspecting it later with Hermit,
but no output was saved, so the kernel didn't get that far.

Some more investigation revealed:
  - Just powering down D4 and pressing reset triggers the issue, too,
  - Pressing the reset switch twice without trying to boot a Linux kernel
    in between also works. So it looks like a mis-initialization in Hermit.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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

Re: Armadillo800EVA legacy defconfig seems busted on my board

[Geert Uytterhoeven]

Hi Simon, Magnus,

On Wed, Aug 27, 2014 at 1:12 AM, Simon Horman <horms@verge.net.au> wrote:
>> > Working fine here with both a 100 Mbps or a Gbps switch.
>> > Gether is supposed to be gigabit, but I only get 100 Mbps.
>> > Ethtool tells me only 10 or 100 Mbps are available?
>> >
>> > What kind of switch do you need? What doesn't work?
>>
>> A shitty semi-managed Netgear Gigabit switch in Autonegotiation does
>> not work, however switching to a different unmanaged Netgear Gigabit
>> switch makes it work. So now i have a 5-port Gigabit switch hooked up
>> in between.
>>
>> I suspect it to be some issue related to PHY settings in the boot loader.
>
> That would not surprise me.
>
> I noticed that I had to turn off spanning tree on the switch my Armadillo is
> connected to else link negotiation would timeout before spanning tree
> completed and thus the link would never come up. This was not a particularly
> crappy switch and my personal view is that the Ethernet situation on the
> boot loader on my Armadillo is less than ideal.

Does it link at Gigabit speed (under Linux), or only 100 Mbps?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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

Re: Armadillo800EVA legacy defconfig seems busted on my board

[Simon Horman]

On Wed, Aug 27, 2014 at 08:39:16AM +0200, Geert Uytterhoeven wrote:
> Hi Simon, Magnus,
> 
> On Wed, Aug 27, 2014 at 1:12 AM, Simon Horman <horms@verge.net.au> wrote:
> >> > Working fine here with both a 100 Mbps or a Gbps switch.
> >> > Gether is supposed to be gigabit, but I only get 100 Mbps.
> >> > Ethtool tells me only 10 or 100 Mbps are available?
> >> >
> >> > What kind of switch do you need? What doesn't work?
> >>
> >> A shitty semi-managed Netgear Gigabit switch in Autonegotiation does
> >> not work, however switching to a different unmanaged Netgear Gigabit
> >> switch makes it work. So now i have a 5-port Gigabit switch hooked up
> >> in between.
> >>
> >> I suspect it to be some issue related to PHY settings in the boot loader.
> >
> > That would not surprise me.
> >
> > I noticed that I had to turn off spanning tree on the switch my Armadillo is
> > connected to else link negotiation would timeout before spanning tree
> > completed and thus the link would never come up. This was not a particularly
> > crappy switch and my personal view is that the Ethernet situation on the
> > boot loader on my Armadillo is less than ideal.
> 
> Does it link at Gigabit speed (under Linux), or only 100 Mbps?

100Mbps.

IIRC this is a hardware limitation of the board.  Perhaps the PHY.
But I only have a very vague memory of a conversation about that.