Hi Russell,
On Wed, Jun 6, 2018 at 11:09 AM, Russell King - ARM Linux
<linux@xxxxxxxxxxxxxxx> wrote:
> On Wed, Jun 06, 2018 at 10:52:34AM +0200, Geert Uytterhoeven wrote:
>> If CONFIG_SMP=n, building a kernel for R-Car Gen2 fails with:
>>
>> arch/arm/mach-shmobile/setup-rcar-gen2.o: In function `rcar_gen2_timer_init':
>> setup-rcar-gen2.c:(.init.text+0x30): undefined reference to `secure_cntvoff_init'
>>
>> Indeed, on R-Car Gen2 SoCs, secure_cntvoff_init() is not only needed for
>> secondary CPUs, but also for the boot CPU. This is most visible on SoCs
>> with Cortex A7 cores (e.g. R-Car E2, cfr. commit 9ce3fa6816c2fb59 ("ARM:
>> shmobile: rcar-gen2: Add CA7 arch_timer initialization for r8a7794")),
>> but Cortex A15 is affected, too.
>>
>> Fix this by always providing secure_cntvoff_init().
>>
>> Reported-by: Arnd Bergmann <arnd@xxxxxxxx>
>> Fixes: 7c607944bc657616 ("ARM: smp: Add initialization of CNTVOFF")
Interestingly, the commit description says:
"It should be done by the bootloader but it is currently not the case,
even for boot CPU because this SoC is booting in secure mode."
^^^^^^^^^^^^^^^^^
So it should be called for !SMP on sunxi, too?
>> Fixes: cad160ed0a94927e ("ARM: shmobile: Convert file to use cntvoff")
>> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>
> This doesn't look right to me, but I don't have secure_cntvoff in any
> tree here that I can look at to check. What if secure_cntvoff contains
> instructions only available on ARMv7 CPUs, and not ARMv4?
Compiled != called.
> It makes no sense (to me) to always build this.
But you're right, making it depend on CPU_V7 is better.
Thanks!
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
