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Diffstat (limited to 'arch/ppc/platforms/chrp_smp.c')
-rw-r--r--arch/ppc/platforms/chrp_smp.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/arch/ppc/platforms/chrp_smp.c b/arch/ppc/platforms/chrp_smp.c
new file mode 100644
index 000000000000..0ea1f7d9e46a
--- /dev/null
+++ b/arch/ppc/platforms/chrp_smp.c
@@ -0,0 +1,98 @@
+/*
+ * 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>
+
+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);
+ call_rtas("freeze-time-base", 0, 1, NULL);
+ timebase_upper = get_tbu();
+ timebase_lower = get_tbl();
+ spin_unlock(&timebase_lock);
+
+ while (timebase_upper || timebase_lower)
+ barrier();
+ call_rtas("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 __chrpdata = {
+ .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,
+};