1 files changed, 316 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/pmac_smp.c b/arch/ppc64/kernel/pmac_smp.c
new file mode 100644
index 000000000000..c27588ede2fe
--- /dev/null
+++ b/arch/ppc64/kernel/pmac_smp.c
@@ -0,0 +1,316 @@
+/*
+ * SMP support for power macintosh.
+ *
+ * We support both the old "powersurge" SMP architecture
+ * and the current Core99 (G4 PowerMac) machines.
+ *
+ * Note that we don't support the very first rev. of
+ * Apple/DayStar 2 CPUs board, the one with the funky
+ * watchdog. Hopefully, none of these should be there except
+ * maybe internally to Apple. I should probably still add some
+ * code to detect this card though and disable SMP. --BenH.
+ *
+ * Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
+ * and Ben Herrenschmidt <benh@kernel.crashing.org>.
+ *
+ * Support for DayStar quad CPU cards
+ * Copyright (C) XLR8, Inc. 1994-2000
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ */
+
+#undef DEBUG
+
+#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/init.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/irq.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/machdep.h>
+#include <asm/pmac_feature.h>
+#include <asm/time.h>
+#include <asm/cacheflush.h>
+#include <asm/keylargo.h>
+#include <asm/pmac_low_i2c.h>
+
+#include "mpic.h"
+
+#ifdef DEBUG
+#define DBG(fmt...) udbg_printf(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+extern void pmac_secondary_start_1(void);
+extern void pmac_secondary_start_2(void);
+extern void pmac_secondary_start_3(void);
+
+extern struct smp_ops_t *smp_ops;
+
+static void (*pmac_tb_freeze)(int freeze);
+static struct device_node *pmac_tb_clock_chip_host;
+static DEFINE_SPINLOCK(timebase_lock);
+static unsigned long timebase;
+
+static void smp_core99_cypress_tb_freeze(int freeze)
+{
+	u8 data;
+	int rc;
+
+	/* Strangely, the device-tree says address is 0xd2, but darwin
+	 * accesses 0xd0 ...
+	 */
+	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_combined);
+	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
+			       0xd0 | pmac_low_i2c_read,
+			       0x81, &data, 1);
+	if (rc != 0)
+		goto bail;
+
+	data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
+
+       	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_stdsub);
+	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
+			       0xd0 | pmac_low_i2c_write,
+			       0x81, &data, 1);
+
+ bail:
+	if (rc != 0) {
+		printk("Cypress Timebase %s rc: %d\n",
+		       freeze ? "freeze" : "unfreeze", rc);
+		panic("Timebase freeze failed !\n");
+	}
+}
+
+static void smp_core99_pulsar_tb_freeze(int freeze)
+{
+	u8 data;
+	int rc;
+
+	/* Strangely, the device-tree says address is 0xd2, but darwin
+	 * accesses 0xd0 ...
+	 */
+	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_combined);
+	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
+			       0xd4 | pmac_low_i2c_read,
+			       0x2e, &data, 1);
+	if (rc != 0)
+		goto bail;
+
+	data = (data & 0x88) | (freeze ? 0x11 : 0x22);
+
+	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_stdsub);
+	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
+			       0xd4 | pmac_low_i2c_write,
+			       0x2e, &data, 1);
+ bail:
+	if (rc != 0) {
+		printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
+		       freeze ? "freeze" : "unfreeze", rc);
+		panic("Timebase freeze failed !\n");
+	}
+}
+
+
+static void smp_core99_give_timebase(void)
+{
+	/* Open i2c bus for synchronous access */
+	if (pmac_low_i2c_open(pmac_tb_clock_chip_host, 0))
+		panic("Can't open i2c for TB sync !\n");
+
+	spin_lock(&timebase_lock);
+	(*pmac_tb_freeze)(1);
+	mb();
+	timebase = get_tb();
+	spin_unlock(&timebase_lock);
+
+	while (timebase)
+		barrier();
+
+	spin_lock(&timebase_lock);
+	(*pmac_tb_freeze)(0);
+	spin_unlock(&timebase_lock);
+
+	/* Close i2c bus */
+	pmac_low_i2c_close(pmac_tb_clock_chip_host);
+}
+
+
+static void __devinit smp_core99_take_timebase(void)
+{
+	while (!timebase)
+		barrier();
+	spin_lock(&timebase_lock);
+	set_tb(timebase >> 32, timebase & 0xffffffff);
+	timebase = 0;
+	spin_unlock(&timebase_lock);
+}
+
+
+static int __init smp_core99_probe(void)
+{
+	struct device_node *cpus;	
+	struct device_node *cc;	
+	int ncpus = 0;
+
+	/* Maybe use systemconfiguration here ? */
+	if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
+
+	/* Count CPUs in the device-tree */
+       	for (cpus = NULL; (cpus = of_find_node_by_type(cpus, "cpu")) != NULL;)
+	       	++ncpus;
+
+	printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
+
+	/* Nothing more to do if less than 2 of them */
+	if (ncpus <= 1)
+		return 1;
+
+	/* Look for the clock chip */
+	for (cc = NULL; (cc = of_find_node_by_name(cc, "i2c-hwclock")) != NULL;) {
+		struct device_node *p = of_get_parent(cc);
+		u32 *reg;
+		int ok;
+		ok = p && device_is_compatible(p, "uni-n-i2c");
+		if (!ok)
+			goto next;
+		reg = (u32 *)get_property(cc, "reg", NULL);
+		if (reg == NULL)
+			goto next;
+		switch (*reg) {
+		case 0xd2:
+			pmac_tb_freeze = smp_core99_cypress_tb_freeze;
+			printk(KERN_INFO "Timebase clock is Cypress chip\n");
+			break;
+		case 0xd4:
+			pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
+			printk(KERN_INFO "Timebase clock is Pulsar chip\n");
+			break;
+		}
+		if (pmac_tb_freeze != NULL) {
+			pmac_tb_clock_chip_host = p;
+			smp_ops->give_timebase = smp_core99_give_timebase;
+			smp_ops->take_timebase = smp_core99_take_timebase;
+			break;
+		}
+	next:
+		of_node_put(p);
+	}
+
+	mpic_request_ipis();
+
+	return ncpus;
+}
+
+static void __init smp_core99_kick_cpu(int nr)
+{
+	int save_vector, j;
+	unsigned long new_vector;
+	unsigned long flags;
+	volatile unsigned int *vector
+		 = ((volatile unsigned int *)(KERNELBASE+0x100));
+
+	if (nr < 1 || nr > 3)
+		return;
+	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu", 0x346);
+
+	local_irq_save(flags);
+	local_irq_disable();
+
+	/* Save reset vector */
+	save_vector = *vector;
+
+	/* Setup fake reset vector that does	
+	 *   b .pmac_secondary_start - KERNELBASE
+	 */
+	switch(nr) {
+	case 1:
+		new_vector = (unsigned long)pmac_secondary_start_1;
+		break;
+	case 2:
+		new_vector = (unsigned long)pmac_secondary_start_2;
+		break;			
+	case 3:
+	default:
+		new_vector = (unsigned long)pmac_secondary_start_3;
+		break;
+	}
+	*vector = 0x48000002 + (new_vector - KERNELBASE);
+
+	/* flush data cache and inval instruction cache */
+	flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
+
+	/* Put some life in our friend */
+	pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
+	paca[nr].cpu_start = 1;
+
+	/* FIXME: We wait a bit for the CPU to take the exception, I should
+	 * instead wait for the entry code to set something for me. Well,
+	 * ideally, all that crap will be done in prom.c and the CPU left
+	 * in a RAM-based wait loop like CHRP.
+	 */
+	for (j = 1; j < 1000000; j++)
+		mb();
+
+	/* Restore our exception vector */
+	*vector = save_vector;
+	flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
+
+	local_irq_restore(flags);
+	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
+}
+
+static void __init smp_core99_setup_cpu(int cpu_nr)
+{
+	/* Setup MPIC */
+	mpic_setup_this_cpu();
+
+	if (cpu_nr == 0) {
+		extern void g5_phy_disable_cpu1(void);
+
+		/* If we didn't start the second CPU, we must take
+		 * it off the bus
+		 */
+		if (num_online_cpus() < 2)		
+			g5_phy_disable_cpu1();
+		if (ppc_md.progress) ppc_md.progress("smp_core99_setup_cpu 0 done", 0x349);
+	}
+}
+
+struct smp_ops_t core99_smp_ops __pmacdata = {
+	.message_pass	= smp_mpic_message_pass,
+	.probe		= smp_core99_probe,
+	.kick_cpu	= smp_core99_kick_cpu,
+	.setup_cpu	= smp_core99_setup_cpu,
+	.give_timebase	= smp_generic_give_timebase,
+	.take_timebase	= smp_generic_take_timebase,
+};
+
+void __init pmac_setup_smp(void)
+{
+	smp_ops = &core99_smp_ops;
+#ifdef CONFIG_HOTPLUG_CPU
+	smp_ops->cpu_enable = generic_cpu_enable;
+	smp_ops->cpu_disable = generic_cpu_disable;
+	smp_ops->cpu_die = generic_cpu_die;
+#endif
+}