LXR linux/arch/powerpc/platforms/44x/iss4xx.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * PPC476 board specific routines
   4 *
   5 * Copyright 2010 Torez Smith, IBM Corporation.
   6 *
   7 * Based on earlier code:
   8 *    Matt Porter <mporter@kernel.crashing.org>
   9 *    Copyright 2002-2005 MontaVista Software Inc.
  10 *
  11 *    Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
  12 *    Copyright (c) 2003-2005 Zultys Technologies
  13 *
  14 *    Rewritten and ported to the merged powerpc tree:
  15 *    Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
  16 */
  17
  18#include <linux/init.h>
  19#include <linux/of_platform.h>
  20#include <linux/rtc.h>
  21
  22#include <asm/machdep.h>
  23#include <asm/prom.h>
  24#include <asm/udbg.h>
  25#include <asm/time.h>
  26#include <asm/uic.h>
  27#include <asm/ppc4xx.h>
  28#include <asm/mpic.h>
  29#include <asm/mmu.h>
  30
  31static const struct of_device_id iss4xx_of_bus[] __initconst = {
  32        { .compatible = "ibm,plb4", },
  33        { .compatible = "ibm,plb6", },
  34        { .compatible = "ibm,opb", },
  35        { .compatible = "ibm,ebc", },
  36        {},
  37};
  38
  39static int __init iss4xx_device_probe(void)
  40{
  41        of_platform_bus_probe(NULL, iss4xx_of_bus, NULL);
  42        of_instantiate_rtc();
  43
  44        return 0;
  45}
  46machine_device_initcall(iss4xx, iss4xx_device_probe);
  47
  48/* We can have either UICs or MPICs */
  49static void __init iss4xx_init_irq(void)
  50{
  51        struct device_node *np;
  52
  53        /* Find top level interrupt controller */
  54        for_each_node_with_property(np, "interrupt-controller") {
  55                if (of_get_property(np, "interrupts", NULL) == NULL)
  56                        break;
  57        }
  58        if (np == NULL)
  59                panic("Can't find top level interrupt controller");
  60
  61        /* Check type and do appropriate initialization */
  62        if (of_device_is_compatible(np, "ibm,uic")) {
  63                uic_init_tree();
  64                ppc_md.get_irq = uic_get_irq;
  65#ifdef CONFIG_MPIC
  66        } else if (of_device_is_compatible(np, "chrp,open-pic")) {
  67                /* The MPIC driver will get everything it needs from the
  68                 * device-tree, just pass 0 to all arguments
  69                 */
  70                struct mpic *mpic = mpic_alloc(np, 0, MPIC_NO_RESET, 0, 0, " MPIC     ");
  71                BUG_ON(mpic == NULL);
  72                mpic_init(mpic);
  73                ppc_md.get_irq = mpic_get_irq;
  74#endif
  75        } else
  76                panic("Unrecognized top level interrupt controller");
  77}
  78
  79#ifdef CONFIG_SMP
  80static void smp_iss4xx_setup_cpu(int cpu)
  81{
  82        mpic_setup_this_cpu();
  83}
  84
  85static int smp_iss4xx_kick_cpu(int cpu)
  86{
  87        struct device_node *cpunode = of_get_cpu_node(cpu, NULL);
  88        const u64 *spin_table_addr_prop;
  89        u32 *spin_table;
  90        extern void start_secondary_47x(void);
  91
  92        BUG_ON(cpunode == NULL);
  93
  94        /* Assume spin table. We could test for the enable-method in
  95         * the device-tree but currently there's little point as it's
  96         * our only supported method
  97         */
  98        spin_table_addr_prop = of_get_property(cpunode, "cpu-release-addr",
  99                                               NULL);
 100        if (spin_table_addr_prop == NULL) {
 101                pr_err("CPU%d: Can't start, missing cpu-release-addr !\n", cpu);
 102                return -ENOENT;
 103        }
 104
 105        /* Assume it's mapped as part of the linear mapping. This is a bit
 106         * fishy but will work fine for now
 107         */
 108        spin_table = (u32 *)__va(*spin_table_addr_prop);
 109        pr_debug("CPU%d: Spin table mapped at %p\n", cpu, spin_table);
 110
 111        spin_table[3] = cpu;
 112        smp_wmb();
 113        spin_table[1] = __pa(start_secondary_47x);
 114        mb();
 115
 116        return 0;
 117}
 118
 119static struct smp_ops_t iss_smp_ops = {
 120        .probe          = smp_mpic_probe,
 121        .message_pass   = smp_mpic_message_pass,
 122        .setup_cpu      = smp_iss4xx_setup_cpu,
 123        .kick_cpu       = smp_iss4xx_kick_cpu,
 124        .give_timebase  = smp_generic_give_timebase,
 125        .take_timebase  = smp_generic_take_timebase,
 126};
 127
 128static void __init iss4xx_smp_init(void)
 129{
 130        if (mmu_has_feature(MMU_FTR_TYPE_47x))
 131                smp_ops = &iss_smp_ops;
 132}
 133
 134#else /* CONFIG_SMP */
 135static void __init iss4xx_smp_init(void) { }
 136#endif /* CONFIG_SMP */
 137
 138static void __init iss4xx_setup_arch(void)
 139{
 140        iss4xx_smp_init();
 141}
 142
 143/*
 144 * Called very early, MMU is off, device-tree isn't unflattened
 145 */
 146static int __init iss4xx_probe(void)
 147{
 148        if (!of_machine_is_compatible("ibm,iss-4xx"))
 149                return 0;
 150
 151        return 1;
 152}
 153
 154define_machine(iss4xx) {
 155        .name                   = "ISS-4xx",
 156        .probe                  = iss4xx_probe,
 157        .progress               = udbg_progress,
 158        .init_IRQ               = iss4xx_init_irq,
 159        .setup_arch             = iss4xx_setup_arch,
 160        .restart                = ppc4xx_reset_system,
 161        .calibrate_decr         = generic_calibrate_decr,
 162};
 163