powerpc: Merge 32-bit CHRP support.

SMP still needs more work but UP gets as far as starting userspace
at least.  This uses the 64-bit-style code for spinning up the cpus.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 94 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/chrp/smp.c b/arch/powerpc/platforms/chrp/smp.c
new file mode 100644
index 00000000000..bf68282670d
--- /dev/null
+++ b/arch/powerpc/platforms/chrp/smp.c
@@ -0,0 +1,94 @@
+/*
+ * Smp support for CHRP machines.
+ *
+ * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
+ * deal of code from the sparc and intel versions.
+ *
+ * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+
+#include <asm/ptrace.h>
+#include <asm/atomic.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/sections.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/smp.h>
+#include <asm/residual.h>
+#include <asm/time.h>
+#include <asm/open_pic.h>
+#include <asm/machdep.h>
+
+extern unsigned long smp_chrp_cpu_nr;
+
+static int __init smp_chrp_probe(void)
+{
+	if (smp_chrp_cpu_nr > 1)
+		openpic_request_IPIs();
+
+	return smp_chrp_cpu_nr;
+}
+
+static void __devinit smp_chrp_kick_cpu(int nr)
+{
+	*(unsigned long *)KERNELBASE = nr;
+	asm volatile("dcbf 0,%0"::"r"(KERNELBASE):"memory");
+}
+
+static void __devinit smp_chrp_setup_cpu(int cpu_nr)
+{
+	if (OpenPIC_Addr)
+		do_openpic_setup_cpu();
+}
+
+static DEFINE_SPINLOCK(timebase_lock);
+static unsigned int timebase_upper = 0, timebase_lower = 0;
+
+void __devinit smp_chrp_give_timebase(void)
+{
+	spin_lock(&timebase_lock);
+	rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
+	timebase_upper = get_tbu();
+	timebase_lower = get_tbl();
+	spin_unlock(&timebase_lock);
+
+	while (timebase_upper || timebase_lower)
+		barrier();
+	rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
+}
+
+void __devinit smp_chrp_take_timebase(void)
+{
+	while (!(timebase_upper || timebase_lower))
+		barrier();
+	spin_lock(&timebase_lock);
+	set_tb(timebase_upper, timebase_lower);
+	timebase_upper = 0;
+	timebase_lower = 0;
+	spin_unlock(&timebase_lock);
+	printk("CPU %i taken timebase\n", smp_processor_id());
+}
+
+/* CHRP with openpic */
+struct smp_ops_t chrp_smp_ops = {
+	.message_pass = smp_openpic_message_pass,
+	.probe = smp_chrp_probe,
+	.kick_cpu = smp_chrp_kick_cpu,
+	.setup_cpu = smp_chrp_setup_cpu,
+	.give_timebase = smp_chrp_give_timebase,
+	.take_timebase = smp_chrp_take_timebase,
+};