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: Uknown 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); 217 218