LXR linux/arch/arm/mach-socfpga/platsmp.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright 2010-2011 Calxeda, Inc.
   4 * Copyright 2012 Pavel Machek <pavel@denx.de>
   5 * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
   6 * Copyright (C) 2012 Altera Corporation
   7 */
   8#include <linux/delay.h>
   9#include <linux/init.h>
  10#include <linux/smp.h>
  11#include <linux/io.h>
  12#include <linux/of.h>
  13#include <linux/of_address.h>
  14
  15#include <asm/cacheflush.h>
  16#include <asm/smp_scu.h>
  17#include <asm/smp_plat.h>
  18
  19#include "core.h"
  20
  21static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
  22{
  23        int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
  24
  25        if (socfpga_cpu1start_addr) {
  26                /* This will put CPU #1 into reset. */
  27                writel(RSTMGR_MPUMODRST_CPU1,
  28                       rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
  29
  30                memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
  31
  32                writel(__pa_symbol(secondary_startup),
  33                       sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));
  34
  35                flush_cache_all();
  36                smp_wmb();
  37                outer_clean_range(0, trampoline_size);
  38
  39                /* This will release CPU #1 out of reset. */
  40                writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
  41        }
  42
  43        return 0;
  44}
  45
  46static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle)
  47{
  48        int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
  49
  50        if (socfpga_cpu1start_addr) {
  51                writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr +
  52                       SOCFPGA_A10_RSTMGR_MODMPURST);
  53                memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
  54
  55                writel(__pa_symbol(secondary_startup),
  56                       sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff));
  57
  58                flush_cache_all();
  59                smp_wmb();
  60                outer_clean_range(0, trampoline_size);
  61
  62                /* This will release CPU #1 out of reset. */
  63                writel(0, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_MODMPURST);
  64        }
  65
  66        return 0;
  67}
  68
  69static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus)
  70{
  71        struct device_node *np;
  72        void __iomem *socfpga_scu_base_addr;
  73
  74        np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
  75        if (!np) {
  76                pr_err("%s: missing scu\n", __func__);
  77                return;
  78        }
  79
  80        socfpga_scu_base_addr = of_iomap(np, 0);
  81        if (!socfpga_scu_base_addr)
  82                return;
  83        scu_enable(socfpga_scu_base_addr);
  84}
  85
  86#ifdef CONFIG_HOTPLUG_CPU
  87/*
  88 * platform-specific code to shutdown a CPU
  89 *
  90 * Called with IRQs disabled
  91 */
  92static void socfpga_cpu_die(unsigned int cpu)
  93{
  94        /* Do WFI. If we wake up early, go back into WFI */
  95        while (1)
  96                cpu_do_idle();
  97}
  98
  99/*
 100 * We need a dummy function so that platform_can_cpu_hotplug() knows
 101 * we support CPU hotplug. However, the function does not need to do
 102 * anything, because CPUs going offline just do WFI. We could reset
 103 * the CPUs but it would increase power consumption.
 104 */
 105static int socfpga_cpu_kill(unsigned int cpu)
 106{
 107        return 1;
 108}
 109#endif
 110
 111static const struct smp_operations socfpga_smp_ops __initconst = {
 112        .smp_prepare_cpus       = socfpga_smp_prepare_cpus,
 113        .smp_boot_secondary     = socfpga_boot_secondary,
 114#ifdef CONFIG_HOTPLUG_CPU
 115        .cpu_die                = socfpga_cpu_die,
 116        .cpu_kill               = socfpga_cpu_kill,
 117#endif
 118};
 119
 120static const struct smp_operations socfpga_a10_smp_ops __initconst = {
 121        .smp_prepare_cpus       = socfpga_smp_prepare_cpus,
 122        .smp_boot_secondary     = socfpga_a10_boot_secondary,
 123#ifdef CONFIG_HOTPLUG_CPU
 124        .cpu_die                = socfpga_cpu_die,
 125        .cpu_kill               = socfpga_cpu_kill,
 126#endif
 127};
 128
 129CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops);
 130CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops);
 131