path: root/arch/x86/kernel/mrst.c

/*
 * mrst.c: Intel Moorestown platform specific setup code
 *
 * (C) Copyright 2008 Intel Corporation
 * Author: Jacob Pan (jacob.jun.pan@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.
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sfi.h>
#include <linux/irq.h>
#include <linux/module.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/mrst.h>
#include <asm/io.h>
#include <asm/i8259.h>
#include <asm/apb_timer.h>

/*
 * the clockevent devices on Moorestown/Medfield can be APBT or LAPIC clock,
 * cmdline option x86_mrst_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
 */

int mrst_timer_options __cpuinitdata;

static u32 sfi_mtimer_usage[SFI_MTMR_MAX_NUM];
static struct sfi_timer_table_entry sfi_mtimer_array[SFI_MTMR_MAX_NUM];
static int mrst_cpu_chip;

int sfi_mtimer_num;

struct sfi_rtc_table_entry sfi_mrtc_array[SFI_MRTC_MAX];
EXPORT_SYMBOL_GPL(sfi_mrtc_array);
int sfi_mrtc_num;

static inline void assign_to_mp_irq(struct mpc_intsrc *m,
				    struct mpc_intsrc *mp_irq)
{
	memcpy(mp_irq, m, sizeof(struct mpc_intsrc));
}

static inline int mp_irq_cmp(struct mpc_intsrc *mp_irq,
				struct mpc_intsrc *m)
{
	return memcmp(mp_irq, m, sizeof(struct mpc_intsrc));
}

static void save_mp_irq(struct mpc_intsrc *m)
{
	int i;

	for (i = 0; i < mp_irq_entries; i++) {
		if (!mp_irq_cmp(&mp_irqs[i], m))
			return;
	}

	assign_to_mp_irq(m, &mp_irqs[mp_irq_entries]);
	if (++mp_irq_entries == MAX_IRQ_SOURCES)
		panic("Max # of irq sources exceeded!!\n");
}

/* parse all the mtimer info to a static mtimer array */
static int __init sfi_parse_mtmr(struct sfi_table_header *table)
{
	struct sfi_table_simple *sb;
	struct sfi_timer_table_entry *pentry;
	struct mpc_intsrc mp_irq;
	int totallen;

	sb = (struct sfi_table_simple *)table;
	if (!sfi_mtimer_num) {
		sfi_mtimer_num = SFI_GET_NUM_ENTRIES(sb,
					struct sfi_timer_table_entry);
		pentry = (struct sfi_timer_table_entry *) sb->pentry;
		totallen = sfi_mtimer_num * sizeof(*pentry);
		memcpy(sfi_mtimer_array, pentry, totallen);
	}

	printk(KERN_INFO "SFI: MTIMER info (num = %d):\n", sfi_mtimer_num);
	pentry = sfi_mtimer_array;
	for (totallen = 0; totallen < sfi_mtimer_num; totallen++, pentry++) {
		printk(KERN_INFO "timer[%d]: paddr = 0x%08x, freq = %dHz,"
			" irq = %d\n", totallen, (u32)pentry->phys_addr,
			pentry->freq_hz, pentry->irq);
			if (!pentry->irq)
				continue;
			mp_irq.type = MP_IOAPIC;
			mp_irq.irqtype = mp_INT;
/* triggering mode edge bit 2-3, active high polarity bit 0-1 */
			mp_irq.irqflag = 5;
			mp_irq.srcbus = 0;
			mp_irq.srcbusirq = pentry->irq;	/* IRQ */
			mp_irq.dstapic = MP_APIC_ALL;
			mp_irq.dstirq = pentry->irq;
			save_mp_irq(&mp_irq);
	}

	return 0;
}

struct sfi_timer_table_entry *sfi_get_mtmr(int hint)
{
	int i;
	if (hint < sfi_mtimer_num) {
		if (!sfi_mtimer_usage[hint]) {
			pr_debug("hint taken for timer %d irq %d\n",\
				hint, sfi_mtimer_array[hint].irq);
			sfi_mtimer_usage[hint] = 1;
			return &sfi_mtimer_array[hint];
		}
	}
	/* take the first timer available */
	for (i = 0; i < sfi_mtimer_num;) {
		if (!sfi_mtimer_usage[i]) {
			sfi_mtimer_usage[i] = 1;
			return &sfi_mtimer_array[i];
		}
		i++;
	}
	return NULL;
}

void sfi_free_mtmr(struct sfi_timer_table_entry *mtmr)
{
	int i;
	for (i = 0; i < sfi_mtimer_num;) {
		if (mtmr->irq == sfi_mtimer_array[i].irq) {
			sfi_mtimer_usage[i] = 0;
			return;
		}
		i++;
	}
}

/* parse all the mrtc info to a global mrtc array */
int __init sfi_parse_mrtc(struct sfi_table_header *table)
{
	struct sfi_table_simple *sb;
	struct sfi_rtc_table_entry *pentry;
	struct mpc_intsrc mp_irq;

	int totallen;

	sb = (struct sfi_table_simple *)table;
	if (!sfi_mrtc_num) {
		sfi_mrtc_num = SFI_GET_NUM_ENTRIES(sb,
						struct sfi_rtc_table_entry);
		pentry = (struct sfi_rtc_table_entry *)sb->pentry;
		totallen = sfi_mrtc_num * sizeof(*pentry);
		memcpy(sfi_mrtc_array, pentry, totallen);
	}

	printk(KERN_INFO "SFI: RTC info (num = %d):\n", sfi_mrtc_num);
	pentry = sfi_mrtc_array;
	for (totallen = 0; totallen < sfi_mrtc_num; totallen++, pentry++) {
		printk(KERN_INFO "RTC[%d]: paddr = 0x%08x, irq = %d\n",
			totallen, (u32)pentry->phys_addr, pentry->irq);
		mp_irq.type = MP_IOAPIC;
		mp_irq.irqtype = mp_INT;
		mp_irq.irqflag = 0;
		mp_irq.srcbus = 0;
		mp_irq.srcbusirq = pentry->irq;	/* IRQ */
		mp_irq.dstapic = MP_APIC_ALL;
		mp_irq.dstirq = pentry->irq;
		save_mp_irq(&mp_irq);
	}
	return 0;
}

static unsigned long __init mrst_calibrate_tsc(void)
{
	unsigned long flags, fast_calibrate;

	local_irq_save(flags);
	fast_calibrate = apbt_quick_calibrate();
	local_irq_restore(flags);

	if (fast_calibrate)
		return fast_calibrate;

	return 0;
}

void __init mrst_time_init(void)
{
	switch (mrst_timer_options) {
	case MRST_TIMER_APBT_ONLY:
		break;
	case MRST_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 */
	sfi_table_parse(SFI_SIG_MTMR, NULL, NULL, sfi_parse_mtmr);
	pre_init_apic_IRQ0();
	apbt_time_init();
}

void __init mrst_rtc_init(void)
{
	sfi_table_parse(SFI_SIG_MRTC, NULL, NULL, sfi_parse_mrtc);
}

int mrst_identify_cpu(void)
{
	return mrst_cpu_chip;
}
EXPORT_SYMBOL_GPL(mrst_identify_cpu);

void __cpuinit mrst_arch_setup(void)
{
	if (boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x27)
		mrst_cpu_chip = MRST_CPU_CHIP_PENWELL;
	else if (boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x26)
		mrst_cpu_chip = MRST_CPU_CHIP_LINCROFT;
	else {
		pr_err("Unknown Moorestown CPU (%d:%d), default to Lincroft\n",
			boot_cpu_data.x86, boot_cpu_data.x86_model);
		mrst_cpu_chip = MRST_CPU_CHIP_LINCROFT;
	}
	pr_debug("Moorestown CPU %s identified\n",
		(mrst_cpu_chip == MRST_CPU_CHIP_LINCROFT) ?
		"Lincroft" : "Penwell");
}

/*
 * Moorestown specific x86_init function overrides and early setup
 * calls.
 */
void __init x86_mrst_early_setup(void)
{
	x86_init.resources.probe_roms = x86_init_noop;
	x86_init.resources.reserve_resources = x86_init_noop;

	x86_init.timers.timer_init = mrst_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 = mrst_arch_setup;

	x86_cpuinit.setup_percpu_clockev = apbt_setup_secondary_clock;

	x86_platform.calibrate_tsc = mrst_calibrate_tsc;
	x86_init.pci.init = pci_mrst_init;
	x86_init.pci.fixup_irqs = x86_init_noop;

	legacy_pic = &null_legacy_pic;

	/* 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;

}

/*
 * 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_mrst_timer(char *arg)
{
	if (!arg)
		return -EINVAL;

	if (strcmp("apbt_only", arg) == 0)
		mrst_timer_options = MRST_TIMER_APBT_ONLY;
	else if (strcmp("lapic_and_apbt", arg) == 0)
		mrst_timer_options = MRST_TIMER_LAPIC_APBT;
	else {
		pr_warning("X86 MRST timer option %s not recognised"
			   " use x86_mrst_timer=apbt_only or lapic_and_apbt\n",
			   arg);
		return -EINVAL;
	}
	return 0;
}
__setup("x86_mrst_timer=", setup_x86_mrst_timer);