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(socfpga_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 /* 58 * Initialise the CPU possible map early - this describes the CPUs 59 * which may be present or become present in the system. 60 */ 61 static void __init socfpga_smp_init_cpus(void) 62 { 63 unsigned int i, ncores; 64 65 ncores = scu_get_core_count(socfpga_scu_base_addr); 66 67 for (i = 0; i < ncores; i++) 68 set_cpu_possible(i, true); 69 70 /* sanity check */ 71 if (ncores > num_possible_cpus()) { 72 pr_warn("socfpga: no. of cores (%d) greater than configured" 73 "maximum of %d - clipping\n", ncores, num_possible_cpus()); 74 ncores = num_possible_cpus(); 75 } 76 77 for (i = 0; i < ncores; i++) 78 set_cpu_possible(i, true); 79 } 80 81 static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus) 82 { 83 scu_enable(socfpga_scu_base_addr); 84 } 85 86 /* 87 * platform-specific code to shutdown a CPU 88 * 89 * Called with IRQs disabled 90 */ 91 static void socfpga_cpu_die(unsigned int cpu) 92 { 93 /* Do WFI. If we wake up early, go back into WFI */ 94 while (1) 95 cpu_do_idle(); 96 } 97 98 struct smp_operations socfpga_smp_ops __initdata = { 99 .smp_init_cpus = socfpga_smp_init_cpus, 100 .smp_prepare_cpus = socfpga_smp_prepare_cpus, 101 .smp_boot_secondary = socfpga_boot_secondary, 102 #ifdef CONFIG_HOTPLUG_CPU 103 .cpu_die = socfpga_cpu_die, 104 #endif 105 }; 106