1 /*
2 * Copyright 2010-2011 Calxeda, Inc.
3 * Copyright 2012 Pavel Machek <pavel@denx.de>
4 * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
5 * Copyright (C) 2012 Altera Corporation
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms and conditions of the GNU General Public License,
9 * version 2, as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License along with
17 * this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19 #include <linux/delay.h>
20 #include <linux/init.h>
21 #include <linux/smp.h>
22 #include <linux/io.h>
23 #include <linux/of.h>
24 #include <linux/of_address.h>
25
26 #include <asm/cacheflush.h>
27 #include <asm/smp_scu.h>
28 #include <asm/smp_plat.h>
29
30 #include "core.h"
31
socfpga_boot_secondary(unsigned int cpu,struct task_struct * idle)32 static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
33 {
34 int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
35
36 if (socfpga_cpu1start_addr) {
37 /* This will put CPU #1 into reset. */
38 writel(RSTMGR_MPUMODRST_CPU1,
39 rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
40
41 memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
42
43 writel(__pa_symbol(secondary_startup),
44 sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));
45
46 flush_cache_all();
47 smp_wmb();
48 outer_clean_range(0, trampoline_size);
49
50 /* This will release CPU #1 out of reset. */
51 writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
52 }
53
54 return 0;
55 }
56
socfpga_a10_boot_secondary(unsigned int cpu,struct task_struct * idle)57 static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle)
58 {
59 int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
60
61 if (socfpga_cpu1start_addr) {
62 writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr +
63 SOCFPGA_A10_RSTMGR_MODMPURST);
64 memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
65
66 writel(__pa_symbol(secondary_startup),
67 sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff));
68
69 flush_cache_all();
70 smp_wmb();
71 outer_clean_range(0, trampoline_size);
72
73 /* This will release CPU #1 out of reset. */
74 writel(0, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_MODMPURST);
75 }
76
77 return 0;
78 }
79
socfpga_smp_prepare_cpus(unsigned int max_cpus)80 static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus)
81 {
82 struct device_node *np;
83 void __iomem *socfpga_scu_base_addr;
84
85 np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
86 if (!np) {
87 pr_err("%s: missing scu\n", __func__);
88 return;
89 }
90
91 socfpga_scu_base_addr = of_iomap(np, 0);
92 if (!socfpga_scu_base_addr)
93 return;
94 scu_enable(socfpga_scu_base_addr);
95 }
96
97 #ifdef CONFIG_HOTPLUG_CPU
98 /*
99 * platform-specific code to shutdown a CPU
100 *
101 * Called with IRQs disabled
102 */
socfpga_cpu_die(unsigned int cpu)103 static void socfpga_cpu_die(unsigned int cpu)
104 {
105 /* Do WFI. If we wake up early, go back into WFI */
106 while (1)
107 cpu_do_idle();
108 }
109
110 /*
111 * We need a dummy function so that platform_can_cpu_hotplug() knows
112 * we support CPU hotplug. However, the function does not need to do
113 * anything, because CPUs going offline just do WFI. We could reset
114 * the CPUs but it would increase power consumption.
115 */
socfpga_cpu_kill(unsigned int cpu)116 static int socfpga_cpu_kill(unsigned int cpu)
117 {
118 return 1;
119 }
120 #endif
121
122 static const struct smp_operations socfpga_smp_ops __initconst = {
123 .smp_prepare_cpus = socfpga_smp_prepare_cpus,
124 .smp_boot_secondary = socfpga_boot_secondary,
125 #ifdef CONFIG_HOTPLUG_CPU
126 .cpu_die = socfpga_cpu_die,
127 .cpu_kill = socfpga_cpu_kill,
128 #endif
129 };
130
131 static const struct smp_operations socfpga_a10_smp_ops __initconst = {
132 .smp_prepare_cpus = socfpga_smp_prepare_cpus,
133 .smp_boot_secondary = socfpga_a10_boot_secondary,
134 #ifdef CONFIG_HOTPLUG_CPU
135 .cpu_die = socfpga_cpu_die,
136 .cpu_kill = socfpga_cpu_kill,
137 #endif
138 };
139
140 CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops);
141 CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops);
142
