arch/x86/platform/intel-mid/intel-mid.c

   1 /*
   2  * intel-mid.c: Intel MID platform setup code
   3  *
   4  * (C) Copyright 2008, 2012 Intel Corporation
   5  * Author: Jacob Pan (jacob.jun.pan@intel.com)
   6  * Author: Sathyanarayanan Kuppuswamy <sathyanarayanan.kuppuswamy@intel.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * as published by the Free Software Foundation; version 2
  11  * of the License.
  12  */
  13
  14 #define pr_fmt(fmt) "intel_mid: " fmt
  15
  16 #include <linux/init.h>
  17 #include <linux/kernel.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/scatterlist.h>
  20 #include <linux/sfi.h>
  21 #include <linux/irq.h>
  22 #include <linux/module.h>
  23 #include <linux/notifier.h>
  24
  25 #include <asm/setup.h>
  26 #include <asm/mpspec_def.h>
  27 #include <asm/hw_irq.h>
  28 #include <asm/apic.h>
  29 #include <asm/io_apic.h>
  30 #include <asm/intel-mid.h>
  31 #include <asm/intel_mid_vrtc.h>
  32 #include <asm/io.h>
  33 #include <asm/i8259.h>
  34 #include <asm/intel_scu_ipc.h>
  35 #include <asm/apb_timer.h>
  36 #include <asm/reboot.h>
  37
  38 #include "intel_mid_weak_decls.h"
  39
  40 /*
  41  * the clockevent devices on Moorestown/Medfield can be APBT or LAPIC clock,
  42  * cmdline option x86_intel_mid_timer can be used to override the configuration
  43  * to prefer one or the other.
  44  * at runtime, there are basically three timer configurations:
  45  * 1. per cpu apbt clock only
  46  * 2. per cpu always-on lapic clocks only, this is Penwell/Medfield only
  47  * 3. per cpu lapic clock (C3STOP) and one apbt clock, with broadcast.
  48  *
  49  * by default (without cmdline option), platform code first detects cpu type
  50  * to see if we are on lincroft or penwell, then set up both lapic or apbt
  51  * clocks accordingly.
  52  * i.e. by default, medfield uses configuration #2, moorestown uses #1.
  53  * config #3 is supported but not recommended on medfield.
  54  *
  55  * rating and feature summary:
  56  * lapic (with C3STOP) --------- 100
  57  * apbt (always-on) ------------ 110
  58  * lapic (always-on,ARAT) ------ 150
  59  */
  60
  61 enum intel_mid_timer_options intel_mid_timer_options;
  62
  63 /* intel_mid_ops to store sub arch ops */
  64 struct intel_mid_ops *intel_mid_ops;
  65 /* getter function for sub arch ops*/
  66 static void *(*get_intel_mid_ops[])(void) = INTEL_MID_OPS_INIT;
  67 enum intel_mid_cpu_type __intel_mid_cpu_chip;
  68 EXPORT_SYMBOL_GPL(__intel_mid_cpu_chip);
  69
  70 static void intel_mid_power_off(void)
  71 {
  72 };
  73
  74 static void intel_mid_reboot(void)
  75 {
  76         intel_scu_ipc_simple_command(IPCMSG_COLD_BOOT, 0);
  77 }
  78
  79 static unsigned long __init intel_mid_calibrate_tsc(void)
  80 {
  81         return 0;
  82 }
  83
  84 static void __init intel_mid_time_init(void)
  85 {
  86         sfi_table_parse(SFI_SIG_MTMR, NULL, NULL, sfi_parse_mtmr);
  87         switch (intel_mid_timer_options) {
  88         case INTEL_MID_TIMER_APBT_ONLY:
  89                 break;
  90         case INTEL_MID_TIMER_LAPIC_APBT:
  91                 x86_init.timers.setup_percpu_clockev = setup_boot_APIC_clock;
  92                 x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
  93                 break;
  94         default:
  95                 if (!boot_cpu_has(X86_FEATURE_ARAT))
  96                         break;
  97                 x86_init.timers.setup_percpu_clockev = setup_boot_APIC_clock;
  98                 x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
  99                 return;
 100         }
 101         /* we need at least one APB timer */
 102         pre_init_apic_IRQ0();
 103         apbt_time_init();
 104 }
 105
 106 static void intel_mid_arch_setup(void)
 107 {
 108         if (boot_cpu_data.x86 != 6) {
 109                 pr_err("Unknown Intel MID CPU (%d:%d), default to Penwell\n",
 110                         boot_cpu_data.x86, boot_cpu_data.x86_model);
 111                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_PENWELL;
 112                 goto out;
 113         }
 114
 115         switch (boot_cpu_data.x86_model) {
 116         case 0x35:
 117                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_CLOVERVIEW;
 118                 break;
 119         case 0x3C:
 120         case 0x4A:
 121                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_TANGIER;
 122                 break;
 123         case 0x27:
 124         default:
 125                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_PENWELL;
 126                 break;
 127         }
 128
 129         if (__intel_mid_cpu_chip < MAX_CPU_OPS(get_intel_mid_ops))
 130                 intel_mid_ops = get_intel_mid_ops[__intel_mid_cpu_chip]();
 131         else {
 132                 intel_mid_ops = get_intel_mid_ops[INTEL_MID_CPU_CHIP_PENWELL]();
 133                 pr_info("ARCH: Unknown SoC, assuming PENWELL!\n");
 134         }
 135
 136 out:
 137         if (intel_mid_ops->arch_setup)
 138                 intel_mid_ops->arch_setup();
 139 }
 140
 141 /* MID systems don't have i8042 controller */
 142 static int intel_mid_i8042_detect(void)
 143 {
 144         return 0;
 145 }
 146
 147 /*
 148  * Moorestown does not have external NMI source nor port 0x61 to report
 149  * NMI status. The possible NMI sources are from pmu as a result of NMI
 150  * watchdog or lock debug. Reading io port 0x61 results in 0xff which
 151  * misled NMI handler.
 152  */
 153 static unsigned char intel_mid_get_nmi_reason(void)
 154 {
 155         return 0;
 156 }
 157
 158 /*
 159  * Moorestown specific x86_init function overrides and early setup
 160  * calls.
 161  */
 162 void __init x86_intel_mid_early_setup(void)
 163 {
 164         x86_init.resources.probe_roms = x86_init_noop;
 165         x86_init.resources.reserve_resources = x86_init_noop;
 166
 167         x86_init.timers.timer_init = intel_mid_time_init;
 168         x86_init.timers.setup_percpu_clockev = x86_init_noop;
 169
 170         x86_init.irqs.pre_vector_init = x86_init_noop;
 171
 172         x86_init.oem.arch_setup = intel_mid_arch_setup;
 173
 174         x86_cpuinit.setup_percpu_clockev = apbt_setup_secondary_clock;
 175
 176         x86_platform.calibrate_tsc = intel_mid_calibrate_tsc;
 177         x86_platform.i8042_detect = intel_mid_i8042_detect;
 178         x86_init.timers.wallclock_init = intel_mid_rtc_init;
 179         x86_platform.get_nmi_reason = intel_mid_get_nmi_reason;
 180
 181         x86_init.pci.init = intel_mid_pci_init;
 182         x86_init.pci.fixup_irqs = x86_init_noop;
 183
 184         legacy_pic = &null_legacy_pic;
 185
 186         pm_power_off = intel_mid_power_off;
 187         machine_ops.emergency_restart  = intel_mid_reboot;
 188
 189         /* Avoid searching for BIOS MP tables */
 190         x86_init.mpparse.find_smp_config = x86_init_noop;
 191         x86_init.mpparse.get_smp_config = x86_init_uint_noop;
 192         set_bit(MP_BUS_ISA, mp_bus_not_pci);
 193 }
 194
 195 /*
 196  * if user does not want to use per CPU apb timer, just give it a lower rating
 197  * than local apic timer and skip the late per cpu timer init.
 198  */
 199 static inline int __init setup_x86_intel_mid_timer(char *arg)
 200 {
 201         if (!arg)
 202                 return -EINVAL;
 203
 204         if (strcmp("apbt_only", arg) == 0)
 205                 intel_mid_timer_options = INTEL_MID_TIMER_APBT_ONLY;
 206         else if (strcmp("lapic_and_apbt", arg) == 0)
 207                 intel_mid_timer_options = INTEL_MID_TIMER_LAPIC_APBT;
 208         else {
 209                 pr_warn("X86 INTEL_MID timer option %s not recognised"
 210                            " use x86_intel_mid_timer=apbt_only or lapic_and_apbt\n",
 211                            arg);
 212                 return -EINVAL;
 213         }
 214         return 0;
 215 }
 216 __setup("x86_intel_mid_timer=", setup_x86_intel_mid_timer);
 217