powerpc/85xx: Add support for SMP initialization

Added 85xx specifc smp_ops structure.  We use ePAPR style boot release
and the MPIC for IPIs at this point.

Additionally added routines for secondary cpu entry and initializtion.

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Trent Piepho <tpiepho@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

2 files changed, 106 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
index cb3054e1001..f0798c09980 100644
--- a/arch/powerpc/platforms/85xx/Makefile
+++ b/arch/powerpc/platforms/85xx/Makefile
@@ -1,6 +1,8 @@
 #
 # Makefile for the PowerPC 85xx linux kernel.
 #
+obj-$(CONFIG_SMP) += smp.o
+
 obj-$(CONFIG_MPC8540_ADS) += mpc85xx_ads.o
 obj-$(CONFIG_MPC8560_ADS) += mpc85xx_ads.o
 obj-$(CONFIG_MPC85xx_CDS) += mpc85xx_cds.o
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
new file mode 100644
index 00000000000..d652c713f49
--- /dev/null
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -0,0 +1,104 @@
+/*
+ * Author: Andy Fleming <afleming@freescale.com>
+ * 	   Kumar Gala <galak@kernel.crashing.org>
+ *
+ * Copyright 2006-2008 Freescale Semiconductor Inc.
+ *
+ * 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.
+ */
+
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+
+#include <asm/machdep.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/mpic.h>
+#include <asm/cacheflush.h>
+
+#include <sysdev/fsl_soc.h>
+
+extern volatile unsigned long __secondary_hold_acknowledge;
+extern void __early_start(void);
+
+#define BOOT_ENTRY_ADDR_UPPER	0
+#define BOOT_ENTRY_ADDR_LOWER	1
+#define BOOT_ENTRY_R3_UPPER	2
+#define BOOT_ENTRY_R3_LOWER	3
+#define BOOT_ENTRY_RESV		4
+#define BOOT_ENTRY_PIR		5
+#define BOOT_ENTRY_R6_UPPER	6
+#define BOOT_ENTRY_R6_LOWER	7
+#define NUM_BOOT_ENTRY		8
+#define SIZE_BOOT_ENTRY		(NUM_BOOT_ENTRY * sizeof(u32))
+
+static void __init
+smp_85xx_kick_cpu(int nr)
+{
+	unsigned long flags;
+	const u64 *cpu_rel_addr;
+	__iomem u32 *bptr_vaddr;
+	struct device_node *np;
+	int n = 0;
+
+	WARN_ON (nr < 0 || nr >= NR_CPUS);
+
+	pr_debug("smp_85xx_kick_cpu: kick CPU #%d\n", nr);
+
+	local_irq_save(flags);
+
+	np = of_get_cpu_node(nr, NULL);
+	cpu_rel_addr = of_get_property(np, "cpu-release-addr", NULL);
+
+	if (cpu_rel_addr == NULL) {
+		printk(KERN_ERR "No cpu-release-addr for cpu %d\n", nr);
+		return;
+	}
+
+	/* Map the spin table */
+	bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
+
+	out_be32(bptr_vaddr + BOOT_ENTRY_PIR, nr);
+	out_be32(bptr_vaddr + BOOT_ENTRY_ADDR_LOWER, __pa(__early_start));
+
+	/* Wait a bit for the CPU to ack. */
+	while ((__secondary_hold_acknowledge != nr) && (++n < 1000))
+		mdelay(1);
+
+	iounmap(bptr_vaddr);
+
+	local_irq_restore(flags);
+
+	pr_debug("waited %d msecs for CPU #%d.\n", n, nr);
+}
+
+static void __init
+smp_85xx_setup_cpu(int cpu_nr)
+{
+	mpic_setup_this_cpu();
+
+	/* Clear any pending timer interrupts */
+	mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS);
+
+	/* Enable decrementer interrupt */
+	mtspr(SPRN_TCR, TCR_DIE);
+}
+
+struct smp_ops_t smp_85xx_ops = {
+	.message_pass = smp_mpic_message_pass,
+	.probe = smp_mpic_probe,
+	.kick_cpu = smp_85xx_kick_cpu,
+	.setup_cpu = smp_85xx_setup_cpu,
+};
+
+void __init
+mpc85xx_smp_init(void)
+{
+	smp_ops = &smp_85xx_ops;
+}