Name: Rewritten Hot-plug CPU Core Infrastructure for PPC
Author: Rusty Russell
Status: Tested on 2.5.15/PPC
Depends: Hotcpu/hotcpu-boot-ppc.patch.gz

D: This introduces hotplug CPU capability for PPC.

diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal working-ppc-2.5-hotcpu/arch/ppc/kernel/smp.c working-ppc-2.5-hotcpu-all/arch/ppc/kernel/smp.c
--- working-ppc-2.5-hotcpu/arch/ppc/kernel/smp.c	Wed May 29 14:05:44 2002
+++ working-ppc-2.5-hotcpu-all/arch/ppc/kernel/smp.c	Wed May 29 18:41:06 2002
@@ -653,6 +653,10 @@
 	char buf[32];
 	int c;
 
+	/* FIXME: we don't take it fully down ATM. --RR */
+	if (cpu_callin_map[cpu])
+		goto up;
+
 	/* create a process for the processor */
 	/* only regs.msr is actually used, and 0 is OK for it */
 	memset(&regs, 0, sizeof(struct pt_regs));
@@ -696,6 +700,7 @@
 	printk("Processor %d found.\n", cpu);
 
 	smp_ops->give_timebase();
+ up:
 	set_bit(cpu, &cpu_online_map);
 	return 0;
 }
@@ -703,5 +708,23 @@
 void smp_cpus_done(unsigned int max_cpus)
 {
 	smp_ops->setup_cpu(0);
+}
+
+/* Upping and downing of CPUs */
+int __cpu_disable(void)
+{
+	unsigned int cpu = smp_processor_id();
+
+	/* FIXME: Should we tell the OpenPIC not to send this CPU
+           interrupts somehow? --RR */
+
+	/* Remove from online map. */
+	clear_bit(cpu, &cpu_online_map);
+	return 0;
+}
+
+void __cpu_die(unsigned int cpu)
+{
+	/* FIXME: Send an IPI to clean it up, kill idle process, etc. -- RR */
 }
 #endif
diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal working-ppc-2.5-hotcpu/include/asm-ppc/smp.h working-ppc-2.5-hotcpu-all/include/asm-ppc/smp.h
--- working-ppc-2.5-hotcpu/include/asm-ppc/smp.h	Tue May 28 16:47:01 2002
+++ working-ppc-2.5-hotcpu-all/include/asm-ppc/smp.h	Wed May 29 15:17:27 2002
@@ -65,16 +65,9 @@
 }
 
 /* Upping and downing of CPUs */
-static inline int __cpu_disable(void)
-{
-	return -ENOSYS;
-}
-
-static inline void __cpu_die(unsigned int cpu)
-{
-}
-
 extern int __cpu_up(unsigned int cpu);
+extern int __cpu_disable(void);
+extern void __cpu_die(unsigned int cpu);
 
 extern int smp_hw_index[];
 #define hard_smp_processor_id() (smp_hw_index[smp_processor_id()])