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 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(virt_to_phys(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 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(virt_to_phys(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 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 /* 98 * platform-specific code to shutdown a CPU 99 * 100 * Called with IRQs disabled 101 */ 102 static void socfpga_cpu_die(unsigned int cpu) 103 { 104 /* Do WFI. If we wake up early, go back into WFI */ 105 while (1) 106 cpu_do_idle(); 107 } 108 109 /* 110 * We need a dummy function so that platform_can_cpu_hotplug() knows 111 * we support CPU hotplug. However, the function does not need to do 112 * anything, because CPUs going offline just do WFI. We could reset 113 * the CPUs but it would increase power consumption. 114 */ 115 static int socfpga_cpu_kill(unsigned int cpu) 116 { 117 return 1; 118 } 119 120 static const struct smp_operations socfpga_smp_ops __initconst = { 121 .smp_prepare_cpus = socfpga_smp_prepare_cpus, 122 .smp_boot_secondary = socfpga_boot_secondary, 123 #ifdef CONFIG_HOTPLUG_CPU 124 .cpu_die = socfpga_cpu_die, 125 .cpu_kill = socfpga_cpu_kill, 126 #endif 127 }; 128 129 static const struct smp_operations socfpga_a10_smp_ops __initconst = { 130 .smp_prepare_cpus = socfpga_smp_prepare_cpus, 131 .smp_boot_secondary = socfpga_a10_boot_secondary, 132 #ifdef CONFIG_HOTPLUG_CPU 133 .cpu_die = socfpga_cpu_die, 134 .cpu_kill = socfpga_cpu_kill, 135 #endif 136 }; 137 138 CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops); 139 CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops); 140