projects / mirror_ubuntu-zesty-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 1ee89e22 GC |
1 | /* |
| 2 | * Symmetric Multi Processing (SMP) support for Marvell EBU Cortex-A9 | |
| 3 | * based SOCs (Armada 375/38x). | |
| 4 | * | |
| 5 | * Copyright (C) 2014 Marvell | |
| 6 | * | |
| 7 | * Gregory CLEMENT <gregory.clement@free-electrons.com> | |
| 8 | * Thomas Petazzoni <thomas.petazzoni@free-electrons.com> | |
| 9 | * | |
| 10 | * This file is licensed under the terms of the GNU General Public | |
| 11 | * License version 2. This program is licensed "as is" without any | |
| 12 | * warranty of any kind, whether express or implied. | |
| 13 | */ | |
| 14 | ||
| 15 | #include <linux/init.h> | |
| 16 | #include <linux/io.h> | |
| 17 | #include <linux/of.h> | |
| 18 | #include <linux/smp.h> | |
| 87384cc0 | 19 | #include <linux/mbus.h> |
| 1ee89e22 GC |
20 | #include <asm/smp_scu.h> |
| 21 | #include <asm/smp_plat.h> | |
| 22 | #include "common.h" | |
| 23 | #include "pmsu.h" | |
| 24 | ||
| 25 | extern void mvebu_cortex_a9_secondary_startup(void); | |
| 26 | ||
| ff6138ad | 27 | static int mvebu_cortex_a9_boot_secondary(unsigned int cpu, |
| 1ee89e22 GC |
28 | struct task_struct *idle) |
| 29 | { | |
| 30 | int ret, hw_cpu; | |
| 31 | ||
| 32 | pr_info("Booting CPU %d\n", cpu); | |
| 33 | ||
| 34 | /* | |
| 35 | * Write the address of secondary startup into the system-wide | |
| 36 | * flags register. The boot monitor waits until it receives a | |
| 37 | * soft interrupt, and then the secondary CPU branches to this | |
| 38 | * address. | |
| 39 | */ | |
| 40 | hw_cpu = cpu_logical_map(cpu); | |
| 305969fb | 41 | if (of_machine_is_compatible("marvell,armada375")) |
| 1ee89e22 | 42 | mvebu_system_controller_set_cpu_boot_addr(mvebu_cortex_a9_secondary_startup); |
| 305969fb GC |
43 | else |
| 44 | mvebu_pmsu_set_cpu_boot_addr(hw_cpu, mvebu_cortex_a9_secondary_startup); | |
| 1ee89e22 | 45 | smp_wmb(); |
| 626d6864 GC |
46 | |
| 47 | /* | |
| 48 | * Doing this before deasserting the CPUs is needed to wake up CPUs | |
| 49 | * in the offline state after using CPU hotplug. | |
| 50 | */ | |
| 51 | arch_send_wakeup_ipi_mask(cpumask_of(cpu)); | |
| 52 | ||
| 1ee89e22 GC |
53 | ret = mvebu_cpu_reset_deassert(hw_cpu); |
| 54 | if (ret) { | |
| 55 | pr_err("Could not start the secondary CPU: %d\n", ret); | |
| 56 | return ret; | |
| 57 | } | |
| 1ee89e22 GC |
58 | |
| 59 | return 0; | |
| 60 | } | |
| 626d6864 GC |
61 | /* |
| 62 | * When a CPU is brought back online, either through CPU hotplug, or | |
| 63 | * because of the boot of a kexec'ed kernel, the PMSU configuration | |
| 64 | * for this CPU might be in the deep idle state, preventing this CPU | |
| 65 | * from receiving interrupts. Here, we therefore take out the current | |
| 66 | * CPU from this state, which was entered by armada_38x_cpu_die() | |
| 67 | * below. | |
| 68 | */ | |
| 69 | static void armada_38x_secondary_init(unsigned int cpu) | |
| 70 | { | |
| 71 | mvebu_v7_pmsu_idle_exit(); | |
| 72 | } | |
| 73 | ||
| 74 | #ifdef CONFIG_HOTPLUG_CPU | |
| 75 | static void armada_38x_cpu_die(unsigned int cpu) | |
| 76 | { | |
| 77 | /* | |
| 78 | * CPU hotplug is implemented by putting offline CPUs into the | |
| 79 | * deep idle sleep state. | |
| 80 | */ | |
| 81 | armada_38x_do_cpu_suspend(true); | |
| 82 | } | |
| 83 | ||
| 84 | /* | |
| 85 | * We need a dummy function, so that platform_can_cpu_hotplug() knows | |
| 86 | * we support CPU hotplug. However, the function does not need to do | |
| 87 | * anything, because CPUs going offline can enter the deep idle state | |
| 88 | * by themselves, without any help from a still alive CPU. | |
| 89 | */ | |
| 90 | static int armada_38x_cpu_kill(unsigned int cpu) | |
| 91 | { | |
| 92 | return 1; | |
| 93 | } | |
| 94 | #endif | |
| 1ee89e22 | 95 | |
| 75305275 | 96 | static const struct smp_operations mvebu_cortex_a9_smp_ops __initconst = { |
| 1ee89e22 | 97 | .smp_boot_secondary = mvebu_cortex_a9_boot_secondary, |
| 1ee89e22 GC |
98 | }; |
| 99 | ||
| 75305275 | 100 | static const struct smp_operations armada_38x_smp_ops __initconst = { |
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101 | .smp_boot_secondary = mvebu_cortex_a9_boot_secondary, |
| 102 | .smp_secondary_init = armada_38x_secondary_init, | |
| 103 | #ifdef CONFIG_HOTPLUG_CPU | |
| 104 | .cpu_die = armada_38x_cpu_die, | |
| 105 | .cpu_kill = armada_38x_cpu_kill, | |
| 106 | #endif | |
| 107 | }; | |
| 108 | ||
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109 | CPU_METHOD_OF_DECLARE(mvebu_armada_375_smp, "marvell,armada-375-smp", |
| 110 | &mvebu_cortex_a9_smp_ops); | |
| 111 | CPU_METHOD_OF_DECLARE(mvebu_armada_380_smp, "marvell,armada-380-smp", | |
| 626d6864 | 112 | &armada_38x_smp_ops); |
| 242ede0b TP |
113 | CPU_METHOD_OF_DECLARE(mvebu_armada_390_smp, "marvell,armada-390-smp", |
| 114 | &armada_38x_smp_ops); |