| /* |
| * SMP support for SoCs with SCU covered by mach-shmobile |
| * |
| * Copyright (C) 2013 Magnus Damm |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| #include <linux/delay.h> |
| #include <linux/init.h> |
| #include <linux/io.h> |
| #include <linux/smp.h> |
| #include <asm/cacheflush.h> |
| #include <asm/smp_plat.h> |
| #include <asm/smp_scu.h> |
| #include <mach/common.h> |
| |
| void __init shmobile_smp_scu_prepare_cpus(unsigned int max_cpus) |
| { |
| /* install boot code shared by all CPUs */ |
| shmobile_boot_fn = virt_to_phys(shmobile_smp_boot); |
| shmobile_boot_arg = MPIDR_HWID_BITMASK; |
| |
| /* enable SCU and cache coherency on booting CPU */ |
| scu_enable(shmobile_scu_base); |
| scu_power_mode(shmobile_scu_base, SCU_PM_NORMAL); |
| } |
| |
| int shmobile_smp_scu_boot_secondary(unsigned int cpu, struct task_struct *idle) |
| { |
| /* For this particular CPU register SCU boot vector */ |
| shmobile_smp_hook(cpu, virt_to_phys(shmobile_boot_scu), |
| (unsigned long)shmobile_scu_base); |
| return 0; |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| void shmobile_smp_scu_cpu_die(unsigned int cpu) |
| { |
| /* For this particular CPU deregister boot vector */ |
| shmobile_smp_hook(cpu, 0, 0); |
| |
| dsb(); |
| flush_cache_all(); |
| |
| /* disable cache coherency */ |
| scu_power_mode(shmobile_scu_base, SCU_PM_POWEROFF); |
| |
| /* jump to shared mach-shmobile sleep / reset code */ |
| shmobile_smp_sleep(); |
| } |
| |
| static int shmobile_smp_scu_psr_core_disabled(int cpu) |
| { |
| unsigned long mask = SCU_PM_POWEROFF << (cpu * 8); |
| |
| if ((__raw_readl(shmobile_scu_base + 8) & mask) == mask) |
| return 1; |
| |
| return 0; |
| } |
| |
| int shmobile_smp_scu_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 (shmobile_smp_scu_psr_core_disabled(cpu)) |
| return 1; |
| |
| mdelay(1); |
| } |
| |
| return 0; |
| } |
| #endif |
