projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| c970d4ef MD |
1 | /* |
| 2 | * SMP support for SoCs with SCU covered by mach-shmobile | |
| 3 | * | |
| 4 | * Copyright (C) 2013 Magnus Damm | |
| 5 | * | |
| 6 | * This program is free software; you can redistribute it and/or modify | |
| 7 | * it under the terms of the GNU General Public License version 2 as | |
| 8 | * published by the Free Software Foundation. | |
| 9 | */ | |
| e7b1c963 | 10 | #include <linux/delay.h> |
| c970d4ef MD |
11 | #include <linux/init.h> |
| 12 | #include <linux/io.h> | |
| 13 | #include <linux/smp.h> | |
| e7b1c963 | 14 | #include <asm/cacheflush.h> |
| c970d4ef MD |
15 | #include <asm/smp_plat.h> |
| 16 | #include <asm/smp_scu.h> | |
| 17 | #include <mach/common.h> | |
| 18 | ||
| 19 | void __init shmobile_smp_scu_prepare_cpus(unsigned int max_cpus) | |
| 20 | { | |
| 1d33a354 MD |
21 | /* install boot code shared by all CPUs */ |
| 22 | shmobile_boot_fn = virt_to_phys(shmobile_smp_boot); | |
| 23 | shmobile_boot_arg = MPIDR_HWID_BITMASK; | |
| c970d4ef MD |
24 | |
| 25 | /* enable SCU and cache coherency on booting CPU */ | |
| 26 | scu_enable(shmobile_scu_base); | |
| 27 | scu_power_mode(shmobile_scu_base, SCU_PM_NORMAL); | |
| 28 | } | |
| 29 | ||
| 30 | int shmobile_smp_scu_boot_secondary(unsigned int cpu, struct task_struct *idle) | |
| 31 | { | |
| 1d33a354 MD |
32 | /* For this particular CPU register SCU boot vector */ |
| 33 | shmobile_smp_hook(cpu, virt_to_phys(shmobile_boot_scu), | |
| 34 | (unsigned long)shmobile_scu_base); | |
| c970d4ef MD |
35 | return 0; |
| 36 | } | |
| e7b1c963 MD |
37 | |
| 38 | #ifdef CONFIG_HOTPLUG_CPU | |
| 39 | void shmobile_smp_scu_cpu_die(unsigned int cpu) | |
| 40 | { | |
| 1d33a354 MD |
41 | /* For this particular CPU deregister boot vector */ |
| 42 | shmobile_smp_hook(cpu, 0, 0); | |
| 43 | ||
| e7b1c963 MD |
44 | dsb(); |
| 45 | flush_cache_all(); | |
| 46 | ||
| 47 | /* disable cache coherency */ | |
| 48 | scu_power_mode(shmobile_scu_base, SCU_PM_POWEROFF); | |
| 49 | ||
| 1d33a354 MD |
50 | /* jump to shared mach-shmobile sleep / reset code */ |
| 51 | shmobile_smp_sleep(); | |
| e7b1c963 MD |
52 | } |
| 53 | ||
| 54 | static int shmobile_smp_scu_psr_core_disabled(int cpu) | |
| 55 | { | |
| 56 | unsigned long mask = SCU_PM_POWEROFF << (cpu * 8); | |
| 57 | ||
| 58 | if ((__raw_readl(shmobile_scu_base + 8) & mask) == mask) | |
| 59 | return 1; | |
| 60 | ||
| 61 | return 0; | |
| 62 | } | |
| 63 | ||
| 64 | int shmobile_smp_scu_cpu_kill(unsigned int cpu) | |
| 65 | { | |
| 66 | int k; | |
| 67 | ||
| 68 | /* this function is running on another CPU than the offline target, | |
| 69 | * here we need wait for shutdown code in platform_cpu_die() to | |
| 70 | * finish before asking SoC-specific code to power off the CPU core. | |
| 71 | */ | |
| 72 | for (k = 0; k < 1000; k++) { | |
| 73 | if (shmobile_smp_scu_psr_core_disabled(cpu)) | |
| 74 | return 1; | |
| 75 | ||
| 76 | mdelay(1); | |
| 77 | } | |
| 78 | ||
| 79 | return 0; | |
| 80 | } | |
| 81 | #endif |