/* * SMP support for R-Mobile / SH-Mobile - r8a7779 portion * * Copyright (C) 2011 Renesas Solutions Corp. * Copyright (C) 2011 Magnus Damm * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/smp.h> #include <linux/spinlock.h> #include <linux/io.h> #include <linux/delay.h> #include <mach/common.h> #include <mach/r8a7779.h> #include <asm/cacheflush.h> #include <asm/smp_plat.h> #include <asm/smp_scu.h> #include <asm/smp_twd.h> #define AVECR IOMEM(0xfe700040) #define R8A7779_SCU_BASE 0xf0000000 static struct r8a7779_pm_ch r8a7779_ch_cpu1 = { .chan_offs = 0x40, /* PWRSR0 .. PWRER0 */ .chan_bit = 1, /* ARM1 */ .isr_bit = 1, /* ARM1 */ }; static struct r8a7779_pm_ch r8a7779_ch_cpu2 = { .chan_offs = 0x40, /* PWRSR0 .. PWRER0 */ .chan_bit = 2, /* ARM2 */ .isr_bit = 2, /* ARM2 */ }; static struct r8a7779_pm_ch r8a7779_ch_cpu3 = { .chan_offs = 0x40, /* PWRSR0 .. PWRER0 */ .chan_bit = 3, /* ARM3 */ .isr_bit = 3, /* ARM3 */ }; static struct r8a7779_pm_ch *r8a7779_ch_cpu[4] = { [1] = &r8a7779_ch_cpu1, [2] = &r8a7779_ch_cpu2, [3] = &r8a7779_ch_cpu3, }; #ifdef CONFIG_HAVE_ARM_TWD static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, R8A7779_SCU_BASE + 0x600, 29); void __init r8a7779_register_twd(void) { twd_local_timer_register(&twd_local_timer); } #endif static int r8a7779_platform_cpu_kill(unsigned int cpu) { struct r8a7779_pm_ch *ch = NULL; int ret = -EIO; cpu = cpu_logical_map(cpu); if (cpu < ARRAY_SIZE(r8a7779_ch_cpu)) ch = r8a7779_ch_cpu[cpu]; if (ch) ret = r8a7779_sysc_power_down(ch); return ret ? ret : 1; } static int __cpuinit r8a7779_boot_secondary(unsigned int cpu, struct task_struct *idle) { struct r8a7779_pm_ch *ch = NULL; int ret = -EIO; cpu = cpu_logical_map(cpu); if (cpu < ARRAY_SIZE(r8a7779_ch_cpu)) ch = r8a7779_ch_cpu[cpu]; if (ch) ret = r8a7779_sysc_power_up(ch); return ret; } static void __init r8a7779_smp_prepare_cpus(unsigned int max_cpus) { scu_enable(shmobile_scu_base); /* Map the reset vector (in headsmp-scu.S) */ __raw_writel(__pa(shmobile_secondary_vector_scu), AVECR); /* enable cache coherency on booting CPU */ scu_power_mode(shmobile_scu_base, SCU_PM_NORMAL); r8a7779_pm_init(); /* power off secondary CPUs */ r8a7779_platform_cpu_kill(1); r8a7779_platform_cpu_kill(2); r8a7779_platform_cpu_kill(3); } static void __init r8a7779_smp_init_cpus(void) { /* setup r8a7779 specific SCU base */ shmobile_scu_base = IOMEM(R8A7779_SCU_BASE); shmobile_smp_init_cpus(scu_get_core_count(shmobile_scu_base)); } #ifdef CONFIG_HOTPLUG_CPU static int r8a7779_scu_psr_core_disabled(int cpu) { unsigned long mask = 3 << (cpu * 8); if ((__raw_readl(shmobile_scu_base + 8) & mask) == mask) return 1; return 0; } static int r8a7779_cpu_kill(unsigned int cpu) { int k; /* this function is running on another CPU than the offline target, * here we need wait for shutdown code in platform_cpu_die() to * finish before asking SoC-specific code to power off the CPU core. */ for (k = 0; k < 1000; k++) { if (r8a7779_scu_psr_core_disabled(cpu)) return r8a7779_platform_cpu_kill(cpu); mdelay(1); } return 0; } static void r8a7779_cpu_die(unsigned int cpu) { dsb(); flush_cache_all(); /* disable cache coherency */ scu_power_mode(shmobile_scu_base, SCU_PM_POWEROFF); /* Endless loop until power off from r8a7779_cpu_kill() */ while (1) cpu_do_idle(); } static int r8a7779_cpu_disable(unsigned int cpu) { /* only CPU1->3 have power domains, do not allow hotplug of CPU0 */ return cpu == 0 ? -EPERM : 0; } #endif /* CONFIG_HOTPLUG_CPU */ struct smp_operations r8a7779_smp_ops __initdata = { .smp_init_cpus = r8a7779_smp_init_cpus, .smp_prepare_cpus = r8a7779_smp_prepare_cpus, .smp_boot_secondary = r8a7779_boot_secondary, #ifdef CONFIG_HOTPLUG_CPU .cpu_kill = r8a7779_cpu_kill, .cpu_die = r8a7779_cpu_die, .cpu_disable = r8a7779_cpu_disable, #endif };