arch/sh/boards/of-generic.c

   1 /*
   2  * SH generic board support, using device tree
   3  *
   4  * Copyright (C) 2015-2016 Smart Energy Instruments, Inc.
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10
  11 #include <linux/of.h>
  12 #include <linux/of_fdt.h>
  13 #include <linux/clocksource.h>
  14 #include <linux/irqchip.h>
  15 #include <linux/clk-provider.h>
  16 #include <asm/machvec.h>
  17 #include <asm/rtc.h>
  18
  19 #ifdef CONFIG_SMP
  20
  21 static void dummy_smp_setup(void)
  22 {
  23 }
  24
  25 static void dummy_prepare_cpus(unsigned int max_cpus)
  26 {
  27 }
  28
  29 static void dummy_start_cpu(unsigned int cpu, unsigned long entry_point)
  30 {
  31 }
  32
  33 static unsigned int dummy_smp_processor_id(void)
  34 {
  35         return 0;
  36 }
  37
  38 static void dummy_send_ipi(unsigned int cpu, unsigned int message)
  39 {
  40 }
  41
  42 static struct plat_smp_ops dummy_smp_ops = {
  43         .smp_setup              = dummy_smp_setup,
  44         .prepare_cpus           = dummy_prepare_cpus,
  45         .start_cpu              = dummy_start_cpu,
  46         .smp_processor_id       = dummy_smp_processor_id,
  47         .send_ipi               = dummy_send_ipi,
  48         .cpu_die                = native_cpu_die,
  49         .cpu_disable            = native_cpu_disable,
  50         .play_dead              = native_play_dead,
  51 };
  52
  53 extern const struct of_cpu_method __cpu_method_of_table[];
  54 const struct of_cpu_method __cpu_method_of_table_sentinel
  55         __section(__cpu_method_of_table_end);
  56
  57 static void sh_of_smp_probe(void)
  58 {
  59         struct device_node *np;
  60         const char *method = NULL;
  61         const struct of_cpu_method *m = __cpu_method_of_table;
  62
  63         pr_info("SH generic board support: scanning for cpus\n");
  64
  65         init_cpu_possible(cpumask_of(0));
  66
  67         for_each_node_by_type(np, "cpu") {
  68                 const __be32 *cell = of_get_property(np, "reg", NULL);
  69                 u64 id = -1;
  70                 if (cell) id = of_read_number(cell, of_n_addr_cells(np));
  71                 if (id < NR_CPUS) {
  72                         if (!method)
  73                                 of_property_read_string(np, "enable-method", &method);
  74                         set_cpu_possible(id, true);
  75                         set_cpu_present(id, true);
  76                         __cpu_number_map[id] = id;
  77                         __cpu_logical_map[id] = id;
  78                 }
  79         }
  80         if (!method) {
  81                 np = of_find_node_by_name(NULL, "cpus");
  82                 of_property_read_string(np, "enable-method", &method);
  83                 of_node_put(np);
  84         }
  85
  86         pr_info("CPU enable method: %s\n", method);
  87         if (method)
  88                 for (; m->method; m++)
  89                         if (!strcmp(m->method, method)) {
  90                                 register_smp_ops(m->ops);
  91                                 return;
  92                         }
  93
  94         register_smp_ops(&dummy_smp_ops);
  95 }
  96
  97 #else
  98
  99 static void sh_of_smp_probe(void)
 100 {
 101 }
 102
 103 #endif
 104
 105 static void noop(void)
 106 {
 107 }
 108
 109 static int noopi(void)
 110 {
 111         return 0;
 112 }
 113
 114 static void __init sh_of_mem_reserve(void)
 115 {
 116         early_init_fdt_reserve_self();
 117         early_init_fdt_scan_reserved_mem();
 118 }
 119
 120 static void __init sh_of_time_init(void)
 121 {
 122         pr_info("SH generic board support: scanning for clocksource devices\n");
 123         timer_probe();
 124 }
 125
 126 static void __init sh_of_setup(char **cmdline_p)
 127 {
 128         struct device_node *root;
 129
 130         board_time_init = sh_of_time_init;
 131
 132         sh_mv.mv_name = "Unknown SH model";
 133         root = of_find_node_by_path("/");
 134         if (root) {
 135                 of_property_read_string(root, "model", &sh_mv.mv_name);
 136                 of_node_put(root);
 137         }
 138
 139         sh_of_smp_probe();
 140 }
 141
 142 static int sh_of_irq_demux(int irq)
 143 {
 144         /* FIXME: eventually this should not be used at all;
 145          * the interrupt controller should set_handle_irq(). */
 146         return irq;
 147 }
 148
 149 static void __init sh_of_init_irq(void)
 150 {
 151         pr_info("SH generic board support: scanning for interrupt controllers\n");
 152         irqchip_init();
 153 }
 154
 155 static int __init sh_of_clk_init(void)
 156 {
 157 #ifdef CONFIG_COMMON_CLK
 158         /* Disabled pending move to COMMON_CLK framework. */
 159         pr_info("SH generic board support: scanning for clk providers\n");
 160         of_clk_init(NULL);
 161 #endif
 162         return 0;
 163 }
 164
 165 static struct sh_machine_vector __initmv sh_of_generic_mv = {
 166         .mv_setup       = sh_of_setup,
 167         .mv_name        = "devicetree", /* replaced by DT root's model */
 168         .mv_irq_demux   = sh_of_irq_demux,
 169         .mv_init_irq    = sh_of_init_irq,
 170         .mv_clk_init    = sh_of_clk_init,
 171         .mv_mode_pins   = noopi,
 172         .mv_mem_init    = noop,
 173         .mv_mem_reserve = sh_of_mem_reserve,
 174 };
 175
 176 struct sh_clk_ops;
 177
 178 void __init __weak arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
 179 {
 180 }
 181
 182 void __init __weak plat_irq_setup(void)
 183 {
 184 }