1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2010-2011 Calxeda, Inc. 4 * Copyright 2012 Pavel Machek <pavel@denx.de> 5 * Based on platsmp.c, Copyright (C) 2002 ARM Ltd. 6 * Copyright (C) 2012 Altera Corporation 7 */ 8 #include <linux/delay.h> 9 #include <linux/init.h> 10 #include <linux/smp.h> 11 #include <linux/io.h> 12 #include <linux/of.h> 13 #include <linux/of_address.h> 14 15 #include <asm/cacheflush.h> 16 #include <asm/smp_scu.h> 17 #include <asm/smp_plat.h> 18 19 #include "core.h" 20 21 static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle) 22 { 23 int trampoline_size = &secondary_trampoline_end - &secondary_trampoline; 24 25 if (socfpga_cpu1start_addr) { 26 /* This will put CPU #1 into reset. */ 27 writel(RSTMGR_MPUMODRST_CPU1, 28 rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST); 29 30 memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size); 31 32 writel(__pa_symbol(secondary_startup), 33 sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff)); 34 35 flush_cache_all(); 36 smp_wmb(); 37 outer_clean_range(0, trampoline_size); 38 39 /* This will release CPU #1 out of reset. */ 40 writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST); 41 } 42 43 return 0; 44 } 45 46 static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle) 47 { 48 int trampoline_size = &secondary_trampoline_end - &secondary_trampoline; 49 50 if (socfpga_cpu1start_addr) { 51 writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr + 52 SOCFPGA_A10_RSTMGR_MODMPURST); 53 memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size); 54 55 writel(__pa_symbol(secondary_startup), 56 sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff)); 57 58 flush_cache_all(); 59 smp_wmb(); 60 outer_clean_range(0, trampoline_size); 61 62 /* This will release CPU #1 out of reset. */ 63 writel(0, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_MODMPURST); 64 } 65 66 return 0; 67 } 68 69 static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus) 70 { 71 struct device_node *np; 72 void __iomem *socfpga_scu_base_addr; 73 74 np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); 75 if (!np) { 76 pr_err("%s: missing scu\n", __func__); 77 return; 78 } 79 80 socfpga_scu_base_addr = of_iomap(np, 0); 81 if (!socfpga_scu_base_addr) 82 return; 83 scu_enable(socfpga_scu_base_addr); 84 } 85 86 #ifdef CONFIG_HOTPLUG_CPU 87 /* 88 * platform-specific code to shutdown a CPU 89 * 90 * Called with IRQs disabled 91 */ 92 static void socfpga_cpu_die(unsigned int cpu) 93 { 94 /* Do WFI. If we wake up early, go back into WFI */ 95 while (1) 96 cpu_do_idle(); 97 } 98 99 /* 100 * We need a dummy function so that platform_can_cpu_hotplug() knows 101 * we support CPU hotplug. However, the function does not need to do 102 * anything, because CPUs going offline just do WFI. We could reset 103 * the CPUs but it would increase power consumption. 104 */ 105 static int socfpga_cpu_kill(unsigned int cpu) 106 { 107 return 1; 108 } 109 #endif 110 111 static const struct smp_operations socfpga_smp_ops __initconst = { 112 .smp_prepare_cpus = socfpga_smp_prepare_cpus, 113 .smp_boot_secondary = socfpga_boot_secondary, 114 #ifdef CONFIG_HOTPLUG_CPU 115 .cpu_die = socfpga_cpu_die, 116 .cpu_kill = socfpga_cpu_kill, 117 #endif 118 }; 119 120 static const struct smp_operations socfpga_a10_smp_ops __initconst = { 121 .smp_prepare_cpus = socfpga_smp_prepare_cpus, 122 .smp_boot_secondary = socfpga_a10_boot_secondary, 123 #ifdef CONFIG_HOTPLUG_CPU 124 .cpu_die = socfpga_cpu_die, 125 .cpu_kill = socfpga_cpu_kill, 126 #endif 127 }; 128 129 CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops); 130 CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops); 131