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/regulator/machine.h>
  20 #include <linux/scatterlist.h>
  21 #include <linux/sfi.h>
  22 #include <linux/irq.h>
  23 #include <linux/export.h>
  24 #include <linux/notifier.h>
  25
  26 #include <asm/setup.h>
  27 #include <asm/mpspec_def.h>
  28 #include <asm/hw_irq.h>
  29 #include <asm/apic.h>
  30 #include <asm/io_apic.h>
  31 #include <asm/intel-mid.h>
  32 #include <asm/intel_mid_vrtc.h>
  33 #include <asm/io.h>
  34 #include <asm/i8259.h>
  35 #include <asm/intel_scu_ipc.h>
  36 #include <asm/apb_timer.h>
  37 #include <asm/reboot.h>
  38
  39 #include "intel_mid_weak_decls.h"
  40
  41 /*
  42  * the clockevent devices on Moorestown/Medfield can be APBT or LAPIC clock,
  43  * cmdline option x86_intel_mid_timer can be used to override the configuration
  44  * to prefer one or the other.
  45  * at runtime, there are basically three timer configurations:
  46  * 1. per cpu apbt clock only
  47  * 2. per cpu always-on lapic clocks only, this is Penwell/Medfield only
  48  * 3. per cpu lapic clock (C3STOP) and one apbt clock, with broadcast.
  49  *
  50  * by default (without cmdline option), platform code first detects cpu type
  51  * to see if we are on lincroft or penwell, then set up both lapic or apbt
  52  * clocks accordingly.
  53  * i.e. by default, medfield uses configuration #2, moorestown uses #1.
  54  * config #3 is supported but not recommended on medfield.
  55  *
  56  * rating and feature summary:
  57  * lapic (with C3STOP) --------- 100
  58  * apbt (always-on) ------------ 110
  59  * lapic (always-on,ARAT) ------ 150
  60  */
  61
  62 enum intel_mid_timer_options intel_mid_timer_options;
  63
  64 /* intel_mid_ops to store sub arch ops */
  65 static struct intel_mid_ops *intel_mid_ops;
  66 /* getter function for sub arch ops*/
  67 static void *(*get_intel_mid_ops[])(void) = INTEL_MID_OPS_INIT;
  68 enum intel_mid_cpu_type __intel_mid_cpu_chip;
  69 EXPORT_SYMBOL_GPL(__intel_mid_cpu_chip);
  70
  71 static void intel_mid_power_off(void)
  72 {
  73         /* Shut down South Complex via PWRMU */
  74         intel_mid_pwr_power_off();
  75
  76         /* Only for Tangier, the rest will ignore this command */
  77         intel_scu_ipc_simple_command(IPCMSG_COLD_OFF, 1);
  78 };
  79
  80 static void intel_mid_reboot(void)
  81 {
  82         intel_scu_ipc_simple_command(IPCMSG_COLD_RESET, 0);
  83 }
  84
  85 static unsigned long __init intel_mid_calibrate_tsc(void)
  86 {
  87         return 0;
  88 }
  89
  90 static void __init intel_mid_setup_bp_timer(void)
  91 {
  92         apbt_time_init();
  93         setup_boot_APIC_clock();
  94 }
  95
  96 static void __init intel_mid_time_init(void)
  97 {
  98         sfi_table_parse(SFI_SIG_MTMR, NULL, NULL, sfi_parse_mtmr);
  99
 100         switch (intel_mid_timer_options) {
 101         case INTEL_MID_TIMER_APBT_ONLY:
 102                 break;
 103         case INTEL_MID_TIMER_LAPIC_APBT:
 104                 /* Use apbt and local apic */
 105                 x86_init.timers.setup_percpu_clockev = intel_mid_setup_bp_timer;
 106                 x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
 107                 return;
 108         default:
 109                 if (!boot_cpu_has(X86_FEATURE_ARAT))
 110                         break;
 111                 /* Lapic only, no apbt */
 112                 x86_init.timers.setup_percpu_clockev = setup_boot_APIC_clock;
 113                 x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
 114                 return;
 115         }
 116
 117         x86_init.timers.setup_percpu_clockev = apbt_time_init;
 118 }
 119
 120 static void intel_mid_arch_setup(void)
 121 {
 122         if (boot_cpu_data.x86 != 6) {
 123                 pr_err("Unknown Intel MID CPU (%d:%d), default to Penwell\n",
 124                         boot_cpu_data.x86, boot_cpu_data.x86_model);
 125                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_PENWELL;
 126                 goto out;
 127         }
 128
 129         switch (boot_cpu_data.x86_model) {
 130         case 0x35:
 131                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_CLOVERVIEW;
 132                 break;
 133         case 0x3C:
 134         case 0x4A:
 135                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_TANGIER;
 136                 break;
 137         case 0x27:
 138         default:
 139                 __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_PENWELL;
 140                 break;
 141         }
 142
 143         if (__intel_mid_cpu_chip < MAX_CPU_OPS(get_intel_mid_ops))
 144                 intel_mid_ops = get_intel_mid_ops[__intel_mid_cpu_chip]();
 145         else {
 146                 intel_mid_ops = get_intel_mid_ops[INTEL_MID_CPU_CHIP_PENWELL]();
 147                 pr_info("ARCH: Unknown SoC, assuming Penwell!\n");
 148         }
 149
 150 out:
 151         if (intel_mid_ops->arch_setup)
 152                 intel_mid_ops->arch_setup();
 153
 154         /*
 155          * Intel MID platforms are using explicitly defined regulators.
 156          *
 157          * Let the regulator core know that we do not have any additional
 158          * regulators left. This lets it substitute unprovided regulators with
 159          * dummy ones:
 160          */
 161         regulator_has_full_constraints();
 162 }
 163
 164 /*
 165  * Moorestown does not have external NMI source nor port 0x61 to report
 166  * NMI status. The possible NMI sources are from pmu as a result of NMI
 167  * watchdog or lock debug. Reading io port 0x61 results in 0xff which
 168  * misled NMI handler.
 169  */
 170 static unsigned char intel_mid_get_nmi_reason(void)
 171 {
 172         return 0;
 173 }
 174
 175 /*
 176  * Moorestown specific x86_init function overrides and early setup
 177  * calls.
 178  */
 179 void __init x86_intel_mid_early_setup(void)
 180 {
 181         x86_init.resources.probe_roms = x86_init_noop;
 182         x86_init.resources.reserve_resources = x86_init_noop;
 183
 184         x86_init.timers.timer_init = intel_mid_time_init;
 185         x86_init.timers.setup_percpu_clockev = x86_init_noop;
 186         x86_init.timers.wallclock_init = intel_mid_rtc_init;
 187
 188         x86_init.irqs.pre_vector_init = x86_init_noop;
 189
 190         x86_init.oem.arch_setup = intel_mid_arch_setup;
 191
 192         x86_cpuinit.setup_percpu_clockev = apbt_setup_secondary_clock;
 193
 194         x86_platform.calibrate_tsc = intel_mid_calibrate_tsc;
 195         x86_platform.get_nmi_reason = intel_mid_get_nmi_reason;
 196
 197         x86_init.pci.arch_init = intel_mid_pci_init;
 198         x86_init.pci.fixup_irqs = x86_init_noop;
 199
 200         legacy_pic = &null_legacy_pic;
 201
 202         /*
 203          * Do nothing for now as everything needed done in
 204          * x86_intel_mid_early_setup() below.
 205          */
 206         x86_init.acpi.reduced_hw_early_init = x86_init_noop;
 207
 208         pm_power_off = intel_mid_power_off;
 209         machine_ops.emergency_restart  = intel_mid_reboot;
 210
 211         /* Avoid searching for BIOS MP tables */
 212         x86_init.mpparse.find_smp_config = x86_init_noop;
 213         x86_init.mpparse.get_smp_config = x86_init_uint_noop;
 214         set_bit(MP_BUS_ISA, mp_bus_not_pci);
 215 }
 216
 217 /*
 218  * if user does not want to use per CPU apb timer, just give it a lower rating
 219  * than local apic timer and skip the late per cpu timer init.
 220  */
 221 static inline int __init setup_x86_intel_mid_timer(char *arg)
 222 {
 223         if (!arg)
 224                 return -EINVAL;
 225
 226         if (strcmp("apbt_only", arg) == 0)
 227                 intel_mid_timer_options = INTEL_MID_TIMER_APBT_ONLY;
 228         else if (strcmp("lapic_and_apbt", arg) == 0)
 229                 intel_mid_timer_options = INTEL_MID_TIMER_LAPIC_APBT;
 230         else {
 231                 pr_warn("X86 INTEL_MID timer option %s not recognised use x86_intel_mid_timer=apbt_only or lapic_and_apbt\n",
 232                         arg);
 233                 return -EINVAL;
 234         }
 235         return 0;
 236 }
 237 __setup("x86_intel_mid_timer=", setup_x86_intel_mid_timer);