target/linux/bcm53xx/patches-4.1/131-ARM-BCM-Clean-up-SMP-support-for-Broadcom-Kona.patch

   1 From 8622d6da5d95293d474c156612fd819fdaf542ec Mon Sep 17 00:00:00 2001
   2 From: Kapil Hali <kapilh@broadcom.com>
   3 Date: Wed, 25 Nov 2015 08:58:53 -0500
   4 Subject: [PATCH 131/134] ARM: BCM: Clean up SMP support for Broadcom Kona
   5
   6 These changes cleans up SMP implementaion for Broadcom's
   7 Kona SoC which are required for handling SMP for iProc
   8 family of SoCs at a single place for BCM NSP and BCM Kona.
   9
  10 Signed-off-by: Kapil Hali <kapilh@broadcom.com>
  11 ---
  12  arch/arm/boot/dts/bcm11351.dtsi |  2 +-
  13  arch/arm/boot/dts/bcm21664.dtsi |  2 +-
  14  arch/arm/mach-bcm/kona_smp.c    | 82 +++++++++++++++++++++++++++--------------
  15  3 files changed, 56 insertions(+), 30 deletions(-)
  16
  17 --- a/arch/arm/boot/dts/bcm11351.dtsi
  18 +++ b/arch/arm/boot/dts/bcm11351.dtsi
  19 @@ -31,7 +31,6 @@
  20                 #address-cells = <1>;
  21                 #size-cells = <0>;
  22                 enable-method = "brcm,bcm11351-cpu-method";
  23 -               secondary-boot-reg = <0x3500417c>;
  24
  25                 cpu0: cpu@0 {
  26                         device_type = "cpu";
  27 @@ -42,6 +41,7 @@
  28                 cpu1: cpu@1 {
  29                         device_type = "cpu";
  30                         compatible = "arm,cortex-a9";
  31 +                       secondary-boot-reg = <0x3500417c>;
  32                         reg = <1>;
  33                 };
  34         };
  35 --- a/arch/arm/boot/dts/bcm21664.dtsi
  36 +++ b/arch/arm/boot/dts/bcm21664.dtsi
  37 @@ -31,7 +31,6 @@
  38                 #address-cells = <1>;
  39                 #size-cells = <0>;
  40                 enable-method = "brcm,bcm11351-cpu-method";
  41 -               secondary-boot-reg = <0x35004178>;
  42
  43                 cpu0: cpu@0 {
  44                         device_type = "cpu";
  45 @@ -42,6 +41,7 @@
  46                 cpu1: cpu@1 {
  47                         device_type = "cpu";
  48                         compatible = "arm,cortex-a9";
  49 +                       secondary-boot-reg = <0x35004178>;
  50                         reg = <1>;
  51                 };
  52         };
  53 --- a/arch/arm/mach-bcm/kona_smp.c
  54 +++ b/arch/arm/mach-bcm/kona_smp.c
  55 @@ -1,5 +1,5 @@
  56  /*
  57 - * Copyright (C) 2014 Broadcom Corporation
  58 + * Copyright (C) 2014-2015 Broadcom Corporation
  59   * Copyright 2014 Linaro Limited
  60   *
  61   * This program is free software; you can redistribute it and/or
  62 @@ -30,9 +30,10 @@
  63
  64  /* Name of device node property defining secondary boot register location */
  65  #define OF_SECONDARY_BOOT      "secondary-boot-reg"
  66 +#define MPIDR_CPUID_BITMASK    0x3
  67
  68  /* I/O address of register used to coordinate secondary core startup */
  69 -static u32     secondary_boot;
  70 +static u32     secondary_boot_addr;
  71
  72  /*
  73   * Enable the Cortex A9 Snoop Control Unit
  74 @@ -78,44 +79,68 @@ static int __init scu_a9_enable(void)
  75  static void __init bcm_smp_prepare_cpus(unsigned int max_cpus)
  76  {
  77         static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 };
  78 -       struct device_node *node;
  79 +       struct device_node *cpus_node = NULL;
  80 +       struct device_node *cpu_node = NULL;
  81         int ret;
  82
  83 -       BUG_ON(secondary_boot);         /* We're called only once */
  84 -
  85         /*
  86          * This function is only called via smp_ops->smp_prepare_cpu().
  87          * That only happens if a "/cpus" device tree node exists
  88          * and has an "enable-method" property that selects the SMP
  89          * operations defined herein.
  90          */
  91 -       node = of_find_node_by_path("/cpus");
  92 -       BUG_ON(!node);
  93 -
  94 -       /*
  95 -        * Our secondary enable method requires a "secondary-boot-reg"
  96 -        * property to specify a register address used to request the
  97 -        * ROM code boot a secondary code.  If we have any trouble
  98 -        * getting this we fall back to uniprocessor mode.
  99 -        */
 100 -       if (of_property_read_u32(node, OF_SECONDARY_BOOT, &secondary_boot)) {
 101 -               pr_err("%s: missing/invalid " OF_SECONDARY_BOOT " property\n",
 102 -                       node->name);
 103 -               ret = -ENOENT;          /* Arrange to disable SMP */
 104 -               goto out;
 105 +       cpus_node = of_find_node_by_path("/cpus");
 106 +       if (!cpus_node)
 107 +               return;
 108 +
 109 +       for_each_child_of_node(cpus_node, cpu_node) {
 110 +               u32 cpuid;
 111 +
 112 +               if (of_node_cmp(cpu_node->type, "cpu"))
 113 +                       continue;
 114 +
 115 +               if (of_property_read_u32(cpu_node, "reg", &cpuid)) {
 116 +                       pr_debug("%s: missing reg property\n",
 117 +                                    cpu_node->full_name);
 118 +                       ret = -ENOENT;
 119 +                       goto out;
 120 +               }
 121 +
 122 +               /*
 123 +                * "secondary-boot-reg" property should be defined only
 124 +                * for secondary cpu
 125 +                */
 126 +               if ((cpuid & MPIDR_CPUID_BITMASK) == 1) {
 127 +                       /*
 128 +                        * Our secondary enable method requires a
 129 +                        * "secondary-boot-reg" property to specify a register
 130 +                        * address used to request the ROM code boot a secondary
 131 +                        * core. If we have any trouble getting this we fall
 132 +                        * back to uniprocessor mode.
 133 +                        */
 134 +                       if (of_property_read_u32(cpu_node,
 135 +                                               OF_SECONDARY_BOOT,
 136 +                                               &secondary_boot_addr)) {
 137 +                               pr_warn("%s: no" OF_SECONDARY_BOOT "property\n",
 138 +                                       cpu_node->name);
 139 +                               ret = -ENOENT;
 140 +                               goto out;
 141 +                       }
 142 +               }
 143         }
 144
 145         /*
 146 -        * Enable the SCU on Cortex A9 based SoCs.  If -ENOENT is
 147 +        * Enable the SCU on Cortex A9 based SoCs. If -ENOENT is
 148          * returned, the SoC reported a uniprocessor configuration.
 149          * We bail on any other error.
 150          */
 151         ret = scu_a9_enable();
 152  out:
 153 -       of_node_put(node);
 154 +       of_node_put(cpu_node);
 155 +       of_node_put(cpus_node);
 156 +
 157         if (ret) {
 158                 /* Update the CPU present map to reflect uniprocessor mode */
 159 -               BUG_ON(ret != -ENOENT);
 160                 pr_warn("disabling SMP\n");
 161                 init_cpu_present(&only_cpu_0);
 162         }
 163 @@ -139,7 +164,7 @@ out:
 164   * - Wait for the secondary boot register to be re-written, which
 165   *   indicates the secondary core has started.
 166   */
 167 -static int bcm_boot_secondary(unsigned int cpu, struct task_struct *idle)
 168 +static int kona_boot_secondary(unsigned int cpu, struct task_struct *idle)
 169  {
 170         void __iomem *boot_reg;
 171         phys_addr_t boot_func;
 172 @@ -154,15 +179,16 @@ static int bcm_boot_secondary(unsigned i
 173                 return -EINVAL;
 174         }
 175
 176 -       if (!secondary_boot) {
 177 +       if (!secondary_boot_addr) {
 178                 pr_err("required secondary boot register not specified\n");
 179                 return -EINVAL;
 180         }
 181
 182 -       boot_reg = ioremap_nocache((phys_addr_t)secondary_boot, sizeof(u32));
 183 +       boot_reg = ioremap_nocache(
 184 +                       (phys_addr_t)secondary_boot_addr, sizeof(u32));
 185         if (!boot_reg) {
 186                 pr_err("unable to map boot register for cpu %u\n", cpu_id);
 187 -               return -ENOSYS;
 188 +               return -ENOMEM;
 189         }
 190
 191         /*
 192 @@ -191,12 +217,12 @@ static int bcm_boot_secondary(unsigned i
 193
 194         pr_err("timeout waiting for cpu %u to start\n", cpu_id);
 195
 196 -       return -ENOSYS;
 197 +       return -ENXIO;
 198  }
 199
 200  static struct smp_operations bcm_smp_ops __initdata = {
 201         .smp_prepare_cpus       = bcm_smp_prepare_cpus,
 202 -       .smp_boot_secondary     = bcm_boot_secondary,
 203 +       .smp_boot_secondary     = kona_boot_secondary,
 204  };
 205  CPU_METHOD_OF_DECLARE(bcm_smp_bcm281xx, "brcm,bcm11351-cpu-method",
 206                         &bcm_smp_ops);