[RFC PATCH 1/1] ACPI: Add weak routines for ACPI CPU Hotplug

[Ashwin Chaugule <ashwin.chaugule@linaro.org>]

Add weak functions for architectures which do not support
hot-adding and removing CPUs which aren't detected at
bootup. (e.g. via MADT).

This helps preserve the Kconfig dependency from:

commit cbfc1bae55bb ("[ACPI] ACPI_HOTPLUG_CPU Kconfig dependency
update")

    prevent:

    HOTPLUG_CPU=y
    ACPI_PROCESSOR=y
    ACPI_HOTPLUG_CPU=n

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
---
 drivers/acpi/acpi_processor.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 58f335c..1fbf252 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -164,6 +164,24 @@ static int acpi_processor_errata(void)
    -------------------------------------------------------------------------- */
 
 #ifdef CONFIG_ACPI_HOTPLUG_CPU
+int __weak acpi_map_cpu(acpi_handle handle,
+		phys_cpuid_t physid, int *pcpu)
+{
+	return -ENODEV;
+}
+
+int __weak acpi_unmap_cpu(int cpu)
+{
+	return -ENODEV;
+}
+
+int __weak arch_register_cpu(int cpu)
+{
+	return -ENODEV;
+}
+
+void __weak arch_unregister_cpu(int cpu) {}
+
 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
 {
 	unsigned long long sta;
-- 
1.9.1