1 /* 2 * SMP support for Emma Mobile EV2 3 * 4 * Copyright (C) 2012 Renesas Solutions Corp. 5 * Copyright (C) 2012 Magnus Damm 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 as published by 9 * the Free Software Foundation; version 2 of the License. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 #include <linux/kernel.h> 21 #include <linux/init.h> 22 #include <linux/smp.h> 23 #include <linux/spinlock.h> 24 #include <linux/io.h> 25 #include <linux/delay.h> 26 #include <mach/common.h> 27 #include <mach/emev2.h> 28 #include <asm/smp_plat.h> 29 #include <asm/smp_scu.h> 30 #include <asm/hardware/gic.h> 31 #include <asm/cacheflush.h> 32 33 #define EMEV2_SCU_BASE 0x1e000000 34 35 static DEFINE_SPINLOCK(scu_lock); 36 static void __iomem *scu_base; 37 38 static void modify_scu_cpu_psr(unsigned long set, unsigned long clr) 39 { 40 unsigned long tmp; 41 42 /* we assume this code is running on a different cpu 43 * than the one that is changing coherency setting */ 44 spin_lock(&scu_lock); 45 tmp = readl(scu_base + 8); 46 tmp &= ~clr; 47 tmp |= set; 48 writel(tmp, scu_base + 8); 49 spin_unlock(&scu_lock); 50 51 } 52 53 unsigned int __init emev2_get_core_count(void) 54 { 55 if (!scu_base) { 56 scu_base = ioremap(EMEV2_SCU_BASE, PAGE_SIZE); 57 emev2_clock_init(); /* need ioremapped SMU */ 58 } 59 60 WARN_ON_ONCE(!scu_base); 61 62 return scu_base ? scu_get_core_count(scu_base) : 1; 63 } 64 65 int emev2_platform_cpu_kill(unsigned int cpu) 66 { 67 return 0; /* not supported yet */ 68 } 69 70 void __cpuinit emev2_secondary_init(unsigned int cpu) 71 { 72 gic_secondary_init(0); 73 } 74 75 int __cpuinit emev2_boot_secondary(unsigned int cpu) 76 { 77 cpu = cpu_logical_map(cpu); 78 79 /* enable cache coherency */ 80 modify_scu_cpu_psr(0, 3 << (cpu * 8)); 81 82 /* Tell ROM loader about our vector (in headsmp.S) */ 83 emev2_set_boot_vector(__pa(shmobile_secondary_vector)); 84 85 gic_raise_softirq(cpumask_of(cpu), 1); 86 return 0; 87 } 88 89 void __init emev2_smp_prepare_cpus(void) 90 { 91 int cpu = cpu_logical_map(0); 92 93 scu_enable(scu_base); 94 95 /* enable cache coherency on CPU0 */ 96 modify_scu_cpu_psr(0, 3 << (cpu * 8)); 97 } 98