ACPI: Don't use acpi_lapic in ACPI core code

Now ARM64 support is being added to ACPI so architecture specific
values can not be used in core ACPI code.

Following on the patch "ACPI / processor: Check if LAPIC is present
during initialization" which uses acpi_lapic in acpi_processor.c,
on ARM64 platform, GIC is used instead of local APIC, so acpi_lapic
is not a suitable value for ARM64.

What is actually important at this point is if there is/are CPU
entry/entries (Local APIC/SAPIC, GICC) in MADT, so introduce
acpi_has_cpu_in_madt() to be arch specific and generic.
Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/ia64/include/asm/acpi.h

@@ -40,6 +40,11 @@ extern int acpi_lapic;
 #define acpi_noirq 0	/* ACPI always enabled on IA64 */
 #define acpi_pci_disabled 0 /* ACPI PCI always enabled on IA64 */
 #define acpi_strict 1	/* no ACPI spec workarounds on IA64 */
+
+static inline bool acpi_has_cpu_in_madt(void)
+{
+	return !!acpi_lapic;
+}
 #endif
 #define acpi_processor_cstate_check(x) (x) /* no idle limits on IA64 :) */
 static inline void disable_acpi(void) { }

arch/x86/include/asm/acpi.h

@@ -121,6 +121,11 @@ static inline void arch_acpi_set_pdc_bits(u32 *buf)
 		buf[2] &= ~(ACPI_PDC_C_C2C3_FFH);
 }
 
+static inline bool acpi_has_cpu_in_madt(void)
+{
+	return !!acpi_lapic;
+}
+
 #else /* !CONFIG_ACPI */
 
 #define acpi_lapic 0

drivers/acpi/acpi_processor.c

@@ -268,7 +268,7 @@ static int acpi_processor_get_info(struct acpi_device *device)
 	pr->apic_id = apic_id;
 
 	cpu_index = acpi_map_cpuid(pr->apic_id, pr->acpi_id);
-	if (!cpu0_initialized && !acpi_lapic) {
+	if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
 		cpu0_initialized = 1;
 		/* Handle UP system running SMP kernel, with no LAPIC in MADT */
 		if ((cpu_index == -1) && (num_online_cpus() == 1))