ARM: Introduce CPU_METHOD_OF_DECLARE() for cpu hotplug/smp
The goal of multi-platform kernels is to remove the need for mach
directories and machine descriptors. To further that goal,
introduce CPU_METHOD_OF_DECLARE() to allow cpu hotplug/smp
support to be separated from the machine descriptors.
Implementers should specify an enable-method property in their
cpus node and then implement a matching set of smp_ops in their
hotplug/smp code, wiring it up with the CPU_METHOD_OF_DECLARE()
macro. When the kernel is compiled we'll collect all the
enable-method smp_ops into one section for use at boot.
At boot time we'll look for an enable-method in each cpu node and
try to match that against all known CPU enable methods in the
kernel. If there are no enable-methods in the cpu nodes we
fallback to the cpus node and try to use any enable-method found
there. If that doesn't work we fall back to the old way of using
the machine descriptor.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: <devicetree@vger.kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Kumar Gala <galak@codeaurora.org>
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index bc2121f..bd02ca7 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -167,6 +167,15 @@
#define CLK_OF_TABLES()
#endif
+#ifdef CONFIG_SMP
+#define CPU_METHOD_OF_TABLES() . = ALIGN(8); \
+ VMLINUX_SYMBOL(__cpu_method_of_table_begin) = .; \
+ *(__cpu_method_of_table) \
+ VMLINUX_SYMBOL(__cpu_method_of_table_end) = .;
+#else
+#define CPU_METHOD_OF_TABLES()
+#endif
+
#define KERNEL_DTB() \
STRUCT_ALIGN(); \
VMLINUX_SYMBOL(__dtb_start) = .; \
@@ -491,6 +500,7 @@
MEM_DISCARD(init.rodata) \
CLK_OF_TABLES() \
CLKSRC_OF_TABLES() \
+ CPU_METHOD_OF_TABLES() \
KERNEL_DTB() \
IRQCHIP_OF_MATCH_TABLE()