[U-Boot] x86: make the LAPIC / IOAPIC construct switchable with Kconfig

There are still systems running which do not have any LAPIC or even
IOAPIC, furthermore the MSRs for that aren't existing and the systems
are crashing on trying setup LAPIC.

So this commit makes the APIC stuff able to switch off for those boards
which dont' have a LAPIC / IOAPIC.

Signed-off-by: Hannes Schmelzer <oe5hpm@oevsv.at>
---

 arch/x86/Kconfig              | 9 +++++++++
 arch/x86/cpu/Makefile         | 2 +-
 arch/x86/cpu/i386/interrupt.c | 3 ++-
 3 files changed, 12 insertions(+), 2 deletions(-)

On Tue, Oct 23, 2018 at 3:03 AM Hannes Schmelzer <oe5hpm@oevsv.at> wrote:
>
> There are still systems running which do not have any LAPIC or even
> IOAPIC, furthermore the MSRs for that aren't existing and the systems

nits: furthermore -> Furthermore. aren't existing -> don't exist

> are crashing on trying setup LAPIC.
>
> So this commit makes the APIC stuff able to switch off for those boards
> which dont' have a LAPIC / IOAPIC.
>
> Signed-off-by: Hannes Schmelzer <oe5hpm@oevsv.at>
> ---
>
>  arch/x86/Kconfig              | 9 +++++++++
>  arch/x86/cpu/Makefile         | 2 +-
>  arch/x86/cpu/i386/interrupt.c | 3 ++-
>  3 files changed, 12 insertions(+), 2 deletions(-)
>

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

and please see comments below.

> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index a1c18d2..00b69c6 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -736,6 +736,15 @@ config I8259_PIC
>           slave) interrupt controllers. Include this to have U-Boot set up
>           the interrupt correctly.
>
> +config APIC
> +       bool
> +       default y
> +       help
> +         The (A)dvanced (P)rogrammable (I)nterrupt (C)ontroller is responsible
> +         for catching interrupts and distributing them to one one more CPU

one one? I think you wanted to say: one more ...

> +         cores. In most cases there is some LAPIC (local) for each core and one
> +         I/O APIC. This conjunction is found on most modern x86 systems.
> +
>  config PINCTRL_ICH6
>         bool
>         help
> diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile
> index f862d8c..54668aa 100644
> --- a/arch/x86/cpu/Makefile
> +++ b/arch/x86/cpu/Makefile
> @@ -35,7 +35,7 @@ obj-$(CONFIG_NORTHBRIDGE_INTEL_IVYBRIDGE) += ivybridge/
>  obj-$(CONFIG_INTEL_QUARK) += quark/
>  obj-$(CONFIG_INTEL_QUEENSBAY) += queensbay/
>  obj-$(CONFIG_INTEL_TANGIER) += tangier/
> -obj-y += lapic.o ioapic.o
> +obj-$(CONFIG_APIC) += lapic.o ioapic.o
>  obj-y += irq.o
>  ifndef CONFIG_$(SPL_)X86_64
>  obj-$(CONFIG_SMP) += mp_init.o
> diff --git a/arch/x86/cpu/i386/interrupt.c b/arch/x86/cpu/i386/interrupt.c
> index ed8423e..2744e2e 100644
> --- a/arch/x86/cpu/i386/interrupt.c
> +++ b/arch/x86/cpu/i386/interrupt.c
> @@ -264,8 +264,9 @@ int interrupt_init(void)
>         i8259_init();
>  #endif
>
> +#ifdef CONFIG_APIC
>         lapic_setup();
> -
> +#endif

Please keep the blank line here and only add the #ifdefs

>         /* Initialize core interrupt and exception functionality of CPU */
>         cpu_init_interrupts();
>

Regards,
Bin