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
  31 static 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
  39 static 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 }
  46 machine_device_initcall(iss4xx, iss4xx_device_probe);
  47
  48 /* We can have either UICs or MPICs */
  49 static 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
  80 static void smp_iss4xx_setup_cpu(int cpu)
  81 {
  82         mpic_setup_this_cpu();
  83 }
  84
  85 static 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
 119 static 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
 128 static 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 */
 135 static void __init iss4xx_smp_init(void) { }
 136 #endif /* CONFIG_SMP */
 137
 138 static 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  */
 146 static int __init iss4xx_probe(void)
 147 {
 148         if (!of_machine_is_compatible("ibm,iss-4xx"))
 149                 return 0;
 150
 151         return 1;
 152 }
 153
 154 define_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 };