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/mach-types.h>
18 #include <asm/smp_scu.h>
19
20 #include <mach/board-eb.h>
21 #include <mach/board-pb11mp.h>
22 #include <mach/board-pbx.h>
23
24 #include <plat/platsmp.h>
25
26 #include "core.h"
27
scu_base_addr(void)28 static void __iomem *scu_base_addr(void)
29 {
30 if (machine_is_realview_eb_mp())
31 return __io_address(REALVIEW_EB11MP_SCU_BASE);
32 else if (machine_is_realview_pb11mp())
33 return __io_address(REALVIEW_TC11MP_SCU_BASE);
34 else if (machine_is_realview_pbx() &&
35 (core_tile_pbx11mp() || core_tile_pbxa9mp()))
36 return __io_address(REALVIEW_PBX_TILE_SCU_BASE);
37 else
38 return (void __iomem *)0;
39 }
40
41 /*
42 * Initialise the CPU possible map early - this describes the CPUs
43 * which may be present or become present in the system.
44 */
realview_smp_init_cpus(void)45 static void __init realview_smp_init_cpus(void)
46 {
47 void __iomem *scu_base = scu_base_addr();
48 unsigned int i, ncores;
49
50 ncores = scu_base ? scu_get_core_count(scu_base) : 1;
51
52 /* sanity check */
53 if (ncores > nr_cpu_ids) {
54 pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
55 ncores, nr_cpu_ids);
56 ncores = nr_cpu_ids;
57 }
58
59 for (i = 0; i < ncores; i++)
60 set_cpu_possible(i, true);
61 }
62
realview_smp_prepare_cpus(unsigned int max_cpus)63 static void __init realview_smp_prepare_cpus(unsigned int max_cpus)
64 {
65
66 scu_enable(scu_base_addr());
67
68 /*
69 * Write the address of secondary startup into the
70 * system-wide flags register. The BootMonitor waits
71 * until it receives a soft interrupt, and then the
72 * secondary CPU branches to this address.
73 */
74 __raw_writel(virt_to_phys(versatile_secondary_startup),
75 __io_address(REALVIEW_SYS_FLAGSSET));
76 }
77
78 struct smp_operations realview_smp_ops __initdata = {
79 .smp_init_cpus = realview_smp_init_cpus,
80 .smp_prepare_cpus = realview_smp_prepare_cpus,
81 .smp_secondary_init = versatile_secondary_init,
82 .smp_boot_secondary = versatile_boot_secondary,
83 #ifdef CONFIG_HOTPLUG_CPU
84 .cpu_die = realview_cpu_die,
85 #endif
86 };
87