The subtarget cleanups made in cabf775 "x86: Refresh subtargets kernel config"
removed some important symbol disable statements, so revert the changes to the
subtarget configs for now.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

Xen support for x86/generic was added in 296772f9.  This commit also
enables it for x86/64.

This was successfully tested with Xen 4.5.

Signed-off-by: Baptiste Jonglez <git@bitsofnetworks.org>

This was done by simply running `make kernel_menuconfig CONFIG_TARGET=subtarget`
and then saving without changing any option.

Having consistent kernel config is important to avoid surprises, such
as the issue fixed with 6f0367c9 (where Xen support was silently
disabled when building the kernel, although it was present in the
initial config)

As far as I understand the build system, this shouldn't have any
user-visible impact, because the build system already merges the
various kernel configs during build.

Signed-off-by: Baptiste Jonglez <git@bitsofnetworks.org>

The Xen serial console has been broken since the xen_domu subtarget
was merged in the generic x86 subtarget (commits 296772f9 and b36e24f3).

The reason for the broken serial console seems to be an IRQ conflict
between the serial console driver and the PATA_LEGACY driver:

[    1.330125] genirq: Flags mismatch irq 8. 00000000 (hvc_console) vs. 00000000 (platform[pata_legacy.4])
[    1.330134] hvc_open: request_irq failed with rc -16.
[    1.330148] Warning: unable to open an initial console.

Just drop the PATA_LEGACY driver from the x86/generic and x86_64
subtargets, since this driver is marked experimental and only supports
very old ISA devices anyway.  It is still included in the x86/legacy
subtarget where it rightfully belongs.

Fixes: FS#787

Signed-off-by: Baptiste Jonglez <git@bitsofnetworks.org>

This is a backport of 641a65fd062987a456216cc4fa91ff2910528261 in master.

This change re-enables PAE for the 32-bit x86 subtarget, which is
interesting in its own right but also necessary for Xen support.

Commit af1d1ebd ("x86: enable 4G high memory support for generic (32bit)
subtarget") inadvertently disabled both PAE and Xen support.

Fixes: FS#908

Cc: Daniel Golle <daniel@makrotopia.org>
Cc: Jo-Philipp Wich <jo@mein.io>
Signed-off-by: Baptiste Jonglez <git@bitsofnetworks.org>

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

Backport of 9b940fe "x86: enable ACPI support for the Geode subtarget".

Fixes FS#577.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

x86 board.d only contains a case for the APU2, not the APU1. This
causes, for example, network configuration not to be created correctly.
Even though the APU1 seems to reaching EOL, there a still a lot of them
out there.

The APU1 and APU2 is configured in the same way and this patch should
also be considered for stable, as the error also exists there.

Signed-off-by: Kristian Evensen <kristian.evensen@gmail.com>

Explicitely disable X2APIC support on legacy targets since the targeted
processor types do not support it anyway there.

Fixes FS#285.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

This is required to fully support a number of 32bit x86 systems equipped
with more than one GB ram, e.g. certain Atom CPU machines.

Ref: https://forum.lede-project.org/t/17-01-1-x86-doesnt-detect-all-of-the-ram/3295

Signed-off-by: Jo-Philipp Wich <jo@mein.io>