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-rw-r--r--arch/x86/platform/intel-mid/intel-mid.c213
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/x86/platform/intel-mid/intel-mid.c b/arch/x86/platform/intel-mid/intel-mid.c
new file mode 100644
index 000000000000..f90e290f689f
--- /dev/null
+++ b/arch/x86/platform/intel-mid/intel-mid.c
@@ -0,0 +1,213 @@
+/*
+ * intel-mid.c: Intel MID platform setup code
+ *
+ * (C) Copyright 2008, 2012 Intel Corporation
+ * Author: Jacob Pan (jacob.jun.pan@intel.com)
+ * Author: Sathyanarayanan Kuppuswamy <sathyanarayanan.kuppuswamy@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+#define pr_fmt(fmt) "intel_mid: " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/scatterlist.h>
+#include <linux/sfi.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+
+#include <asm/setup.h>
+#include <asm/mpspec_def.h>
+#include <asm/hw_irq.h>
+#include <asm/apic.h>
+#include <asm/io_apic.h>
+#include <asm/intel-mid.h>
+#include <asm/intel_mid_vrtc.h>
+#include <asm/io.h>
+#include <asm/i8259.h>
+#include <asm/intel_scu_ipc.h>
+#include <asm/apb_timer.h>
+#include <asm/reboot.h>
+
+/*
+ * the clockevent devices on Moorestown/Medfield can be APBT or LAPIC clock,
+ * cmdline option x86_intel_mid_timer can be used to override the configuration
+ * to prefer one or the other.
+ * at runtime, there are basically three timer configurations:
+ * 1. per cpu apbt clock only
+ * 2. per cpu always-on lapic clocks only, this is Penwell/Medfield only
+ * 3. per cpu lapic clock (C3STOP) and one apbt clock, with broadcast.
+ *
+ * by default (without cmdline option), platform code first detects cpu type
+ * to see if we are on lincroft or penwell, then set up both lapic or apbt
+ * clocks accordingly.
+ * i.e. by default, medfield uses configuration #2, moorestown uses #1.
+ * config #3 is supported but not recommended on medfield.
+ *
+ * rating and feature summary:
+ * lapic (with C3STOP) --------- 100
+ * apbt (always-on) ------------ 110
+ * lapic (always-on,ARAT) ------ 150
+ */
+
+enum intel_mid_timer_options intel_mid_timer_options;
+
+enum intel_mid_cpu_type __intel_mid_cpu_chip;
+EXPORT_SYMBOL_GPL(__intel_mid_cpu_chip);
+
+static void intel_mid_power_off(void)
+{
+}
+
+static void intel_mid_reboot(void)
+{
+ intel_scu_ipc_simple_command(IPCMSG_COLD_BOOT, 0);
+}
+
+static unsigned long __init intel_mid_calibrate_tsc(void)
+{
+ unsigned long fast_calibrate;
+ u32 lo, hi, ratio, fsb;
+
+ rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
+ pr_debug("IA32 perf status is 0x%x, 0x%0x\n", lo, hi);
+ ratio = (hi >> 8) & 0x1f;
+ pr_debug("ratio is %d\n", ratio);
+ if (!ratio) {
+ pr_err("read a zero ratio, should be incorrect!\n");
+ pr_err("force tsc ratio to 16 ...\n");
+ ratio = 16;
+ }
+ rdmsr(MSR_FSB_FREQ, lo, hi);
+ if ((lo & 0x7) == 0x7)
+ fsb = PENWELL_FSB_FREQ_83SKU;
+ else
+ fsb = PENWELL_FSB_FREQ_100SKU;
+ fast_calibrate = ratio * fsb;
+ pr_debug("read penwell tsc %lu khz\n", fast_calibrate);
+ lapic_timer_frequency = fsb * 1000 / HZ;
+ /* mark tsc clocksource as reliable */
+ set_cpu_cap(&boot_cpu_data, X86_FEATURE_TSC_RELIABLE);
+
+ if (fast_calibrate)
+ return fast_calibrate;
+
+ return 0;
+}
+
+static void __init intel_mid_time_init(void)
+{
+ sfi_table_parse(SFI_SIG_MTMR, NULL, NULL, sfi_parse_mtmr);
+ switch (intel_mid_timer_options) {
+ case INTEL_MID_TIMER_APBT_ONLY:
+ break;
+ case INTEL_MID_TIMER_LAPIC_APBT:
+ x86_init.timers.setup_percpu_clockev = setup_boot_APIC_clock;
+ x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
+ break;
+ default:
+ if (!boot_cpu_has(X86_FEATURE_ARAT))
+ break;
+ x86_init.timers.setup_percpu_clockev = setup_boot_APIC_clock;
+ x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
+ return;
+ }
+ /* we need at least one APB timer */
+ pre_init_apic_IRQ0();
+ apbt_time_init();
+}
+
+static void intel_mid_arch_setup(void)
+{
+ if (boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x27)
+ __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_PENWELL;
+ else {
+ pr_err("Unknown Intel MID CPU (%d:%d), default to Penwell\n",
+ boot_cpu_data.x86, boot_cpu_data.x86_model);
+ __intel_mid_cpu_chip = INTEL_MID_CPU_CHIP_PENWELL;
+ }
+}
+
+/* MID systems don't have i8042 controller */
+static int intel_mid_i8042_detect(void)
+{
+ return 0;
+}
+
+/*
+ * Moorestown does not have external NMI source nor port 0x61 to report
+ * NMI status. The possible NMI sources are from pmu as a result of NMI
+ * watchdog or lock debug. Reading io port 0x61 results in 0xff which
+ * misled NMI handler.
+ */
+static unsigned char intel_mid_get_nmi_reason(void)
+{
+ return 0;
+}
+
+/*
+ * Moorestown specific x86_init function overrides and early setup
+ * calls.
+ */
+void __init x86_intel_mid_early_setup(void)
+{
+ x86_init.resources.probe_roms = x86_init_noop;
+ x86_init.resources.reserve_resources = x86_init_noop;
+
+ x86_init.timers.timer_init = intel_mid_time_init;
+ x86_init.timers.setup_percpu_clockev = x86_init_noop;
+
+ x86_init.irqs.pre_vector_init = x86_init_noop;
+
+ x86_init.oem.arch_setup = intel_mid_arch_setup;
+
+ x86_cpuinit.setup_percpu_clockev = apbt_setup_secondary_clock;
+
+ x86_platform.calibrate_tsc = intel_mid_calibrate_tsc;
+ x86_platform.i8042_detect = intel_mid_i8042_detect;
+ x86_init.timers.wallclock_init = intel_mid_rtc_init;
+ x86_platform.get_nmi_reason = intel_mid_get_nmi_reason;
+
+ x86_init.pci.init = intel_mid_pci_init;
+ x86_init.pci.fixup_irqs = x86_init_noop;
+
+ legacy_pic = &null_legacy_pic;
+
+ pm_power_off = intel_mid_power_off;
+ machine_ops.emergency_restart = intel_mid_reboot;
+
+ /* Avoid searching for BIOS MP tables */
+ x86_init.mpparse.find_smp_config = x86_init_noop;
+ x86_init.mpparse.get_smp_config = x86_init_uint_noop;
+ set_bit(MP_BUS_ISA, mp_bus_not_pci);
+}
+
+/*
+ * if user does not want to use per CPU apb timer, just give it a lower rating
+ * than local apic timer and skip the late per cpu timer init.
+ */
+static inline int __init setup_x86_intel_mid_timer(char *arg)
+{
+ if (!arg)
+ return -EINVAL;
+
+ if (strcmp("apbt_only", arg) == 0)
+ intel_mid_timer_options = INTEL_MID_TIMER_APBT_ONLY;
+ else if (strcmp("lapic_and_apbt", arg) == 0)
+ intel_mid_timer_options = INTEL_MID_TIMER_LAPIC_APBT;
+ else {
+ pr_warn("X86 INTEL_MID timer option %s not recognised"
+ " use x86_intel_mid_timer=apbt_only or lapic_and_apbt\n",
+ arg);
+ return -EINVAL;
+ }
+ return 0;
+}
+__setup("x86_intel_mid_timer=", setup_x86_intel_mid_timer);
+
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