1/*
 2 *  linux/arch/arm/mach-realview/platsmp.c
 3 *
 4 *  Copyright (C) 2002 ARM Ltd.
 5 *  All Rights Reserved
 6 *
 7 * This program is free software; you can redistribute it and/or modify
 8 * it under the terms of the GNU General Public License version 2 as
 9 * published by the Free Software Foundation.
10 */
11#include <linux/init.h>
12#include <linux/errno.h>
13#include <linux/smp.h>
14#include <linux/io.h>
15
16#include <mach/hardware.h>
17#include <asm/hardware/gic.h>
18#include <asm/mach-types.h>
19#include <asm/smp_scu.h>
20
21#include <mach/board-eb.h>
22#include <mach/board-pb11mp.h>
23#include <mach/board-pbx.h>
24
25#include "core.h"
26
27extern void versatile_secondary_startup(void);
28
29static void __iomem *scu_base_addr(void)
30{
31	if (machine_is_realview_eb_mp())
32		return __io_address(REALVIEW_EB11MP_SCU_BASE);
33	else if (machine_is_realview_pb11mp())
34		return __io_address(REALVIEW_TC11MP_SCU_BASE);
35	else if (machine_is_realview_pbx() &&
36		 (core_tile_pbx11mp() || core_tile_pbxa9mp()))
37		return __io_address(REALVIEW_PBX_TILE_SCU_BASE);
38	else
39		return (void __iomem *)0;
40}
41
42/*
43 * Initialise the CPU possible map early - this describes the CPUs
44 * which may be present or become present in the system.
45 */
46void __init smp_init_cpus(void)
47{
48	void __iomem *scu_base = scu_base_addr();
49	unsigned int i, ncores;
50
51	ncores = scu_base ? scu_get_core_count(scu_base) : 1;
52
53	/* sanity check */
54	if (ncores > nr_cpu_ids) {
55		pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
56			ncores, nr_cpu_ids);
57		ncores = nr_cpu_ids;
58	}
59
60	for (i = 0; i < ncores; i++)
61		set_cpu_possible(i, true);
62
63	set_smp_cross_call(gic_raise_softirq);
64}
65
66void __init platform_smp_prepare_cpus(unsigned int max_cpus)
67{
68
69	scu_enable(scu_base_addr());
70
71	/*
72	 * Write the address of secondary startup into the
73	 * system-wide flags register. The BootMonitor waits
74	 * until it receives a soft interrupt, and then the
75	 * secondary CPU branches to this address.
76	 */
77	__raw_writel(virt_to_phys(versatile_secondary_startup),
78		     __io_address(REALVIEW_SYS_FLAGSSET));
79}