clocksource: apb: Share APB timer code with other platforms

The APB timers are an IP block from Synopsys (DesignWare APB timers)
and are also found in other systems including ARM SoC's.  This patch
adds functions for creating clock_event_devices and clocksources from
APB timers but does not do the resource allocation.  This is handled
in a higher layer to allow the timers to be created from multiple
methods such as platform_devices.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index da349723d411..10ce62f17ea1 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -617,6 +617,7 @@ config HPET_EMULATE_RTC
 config APB_TIMER
        def_bool y if MRST
        prompt "Langwell APB Timer Support" if X86_MRST
+       select DW_APB_TIMER
        help
          APB timer is the replacement for 8254, HPET on X86 MID platforms.
          The APBT provides a stable time base on SMP