/*
 * Copyright (C) 2010 Google, Inc.
 *
 * Author:
 *	Colin Cross <ccross@google.com>
 *
 * Copyright (C) 2010-2011, NVIDIA Corporation
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/debugfs.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/seq_file.h>

#include <asm/hardware/gic.h>

#include <mach/iomap.h>
#include <mach/legacy_irq.h>
#include <mach/suspend.h>

#include "board.h"
#include "power.h"

#define PMC_CTRL		0x0
#define PMC_CTRL_LATCH_WAKEUPS	(1 << 5)
#define PMC_WAKE_MASK		0xc
#define PMC_WAKE_LEVEL		0x10
#define PMC_WAKE_STATUS		0x14
#define PMC_SW_WAKE_STATUS	0x18
#define PMC_DPD_SAMPLE  	0x20
#ifndef CONFIG_ARCH_TEGRA_2x_SOC
#define PMC_WAKE2_MASK		0x160
#define PMC_WAKE2_LEVEL		0x164
#define PMC_WAKE2_STATUS       	0x168
#define PMC_SW_WAKE2_STATUS	0x16C
#endif

static void __iomem *pmc = IO_ADDRESS(TEGRA_PMC_BASE);

static u64 tegra_lp0_wake_enb;
static u64 tegra_lp0_wake_level;
static u64 tegra_lp0_wake_level_any;

static unsigned int tegra_wake_irq_count[64];

/* ensures that sufficient time is passed for a register write to
 * serialize into the 32KHz domain */
static void pmc_32kwritel(u32 val, unsigned long offs)
{
	writel(val, pmc + offs);
	udelay(130);
}

static inline void write_pmc_wake_mask(u64 value)
{
	writel((u32)value, pmc + PMC_WAKE_MASK);
#ifndef CONFIG_ARCH_TEGRA_2x_SOC
	__raw_writel((u32)(value >> 32), pmc + PMC_WAKE2_MASK);
#endif
}

static inline u64 read_pmc_wake_level(void)
{
	u64 reg;

#ifdef CONFIG_ARCH_TEGRA_2x_SOC
	reg = readl(pmc + PMC_WAKE_LEVEL);
#else
	reg = __raw_readl(pmc + PMC_WAKE_LEVEL);
	reg |= ((u64)readl(pmc + PMC_WAKE2_LEVEL)) << 32;
#endif
	return reg;
}

static inline void write_pmc_wake_level(u64 value)
{
	writel((u32)value, pmc + PMC_WAKE_LEVEL);
#ifndef CONFIG_ARCH_TEGRA_2x_SOC
	__raw_writel((u32)(value >> 32), pmc + PMC_WAKE2_LEVEL);
#endif
}

static inline u64 read_pmc_wake_status(void)
{
	u64 reg;

#ifdef CONFIG_ARCH_TEGRA_2x_SOC
	reg = readl(pmc + PMC_WAKE_STATUS);
#else
	reg = __raw_readl(pmc + PMC_WAKE_STATUS);
	reg |= ((u64)readl(pmc + PMC_WAKE2_STATUS)) << 32;
#endif
	return reg;
}

static inline u64 read_pmc_sw_wake_status(void)
{
	u64 reg;

#ifdef CONFIG_ARCH_TEGRA_2x_SOC
	reg = readl(pmc + PMC_SW_WAKE_STATUS);
#else
	reg = __raw_readl(pmc + PMC_SW_WAKE_STATUS);
	reg |= ((u64)readl(pmc + PMC_SW_WAKE2_STATUS)) << 32;
#endif
	return reg;
}

static inline void clear_pmc_sw_wake_status(void)
{
	pmc_32kwritel(0, PMC_SW_WAKE_STATUS);
#ifndef CONFIG_ARCH_TEGRA_2x_SOC
	pmc_32kwritel(0, PMC_SW_WAKE2_STATUS);
#endif
}

int tegra_set_lp0_wake(int irq, int enable)
{
	int wake = tegra_irq_to_wake(irq);

	if (wake < 0)
		return -EINVAL;

	if (enable)
		tegra_lp0_wake_enb |= 1ull << wake;
	else
		tegra_lp0_wake_enb &= ~(1ull << wake);

	return 0;
}

int tegra_set_lp0_wake_type(int irq, int flow_type)
{
	int wake = tegra_irq_to_wake(irq);

	if (wake < 0)
		return 0;

	switch (flow_type) {
	case IRQF_TRIGGER_FALLING:
	case IRQF_TRIGGER_LOW:
		tegra_lp0_wake_level &= ~(1 << wake);
		tegra_lp0_wake_level_any &= ~(1 << wake);
		break;
	case IRQF_TRIGGER_HIGH:
	case IRQF_TRIGGER_RISING:
		tegra_lp0_wake_level |= 1 << wake;
		tegra_lp0_wake_level_any &= ~(1 << wake);
		break;

	case IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING:
		tegra_lp0_wake_level_any |= 1 << wake;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}


int tegra_set_lp1_wake(int irq, int enable)
{
	return tegra_legacy_irq_set_wake(irq, enable);
}

void tegra_set_lp0_wake_pads(u64 wake_enb, u64 wake_level, u64 wake_any)
{
	u32 temp;
	u64 status;
	u64 lvl;

	wake_level &= wake_enb;
	wake_any &= wake_enb;

	wake_level |= (tegra_lp0_wake_level & tegra_lp0_wake_enb);
	wake_any |= (tegra_lp0_wake_level_any & tegra_lp0_wake_enb);

	wake_enb |= tegra_lp0_wake_enb;

	clear_pmc_sw_wake_status();
	temp = readl(pmc + PMC_CTRL);
	temp |= PMC_CTRL_LATCH_WAKEUPS;
	pmc_32kwritel(temp, PMC_CTRL);
	temp &= ~PMC_CTRL_LATCH_WAKEUPS;
	pmc_32kwritel(temp, PMC_CTRL);
	status = read_pmc_sw_wake_status();
	lvl = read_pmc_wake_level();

	/* flip the wakeup trigger for any-edge triggered pads
	 * which are currently asserting as wakeups */
	lvl ^= status;
	lvl &= wake_any;

	wake_level |= lvl;

	write_pmc_wake_level(wake_level);
	/* Enable DPD sample to trigger sampling pads data and direction
	 * in which pad will be driven during lp0 mode*/
	writel(0x1, pmc + PMC_DPD_SAMPLE);

	write_pmc_wake_mask(wake_enb);
}

#ifdef CONFIG_PM
static void tegra_irq_handle_wake_helper(unsigned long wake_status)
{
	int wake;
	int irq;
	struct irq_desc *desc;

	for_each_set_bit(wake, &wake_status, sizeof(wake_status) * 8) {
		irq = tegra_wake_to_irq(wake);
		if (!irq) {
			pr_info("Resume caused by WAKE%d\n", wake);
			continue;
		}

		desc = irq_to_desc(irq);
		if (!desc || !desc->action || !desc->action->name) {
			pr_info("Resume caused by WAKE%d, irq %d\n", wake, irq);
			continue;
		}

		pr_info("Resume caused by WAKE%d, %s\n", wake,
			desc->action->name);

		tegra_wake_irq_count[wake]++;

		generic_handle_irq(irq);
	}
}

static void tegra_irq_handle_wake(void)
{
	u64 wake_status = read_pmc_wake_status();

	tegra_irq_handle_wake_helper((unsigned long)wake_status);
#ifndef CONFIG_ARCH_TEGRA_2x_SOC
	tegra_irq_handle_wake_helper((unsigned long)(wake_status >> 32));
#endif
}
#endif

static void tegra_mask(unsigned int irq)
{
	gic_mask_irq(irq);
	tegra_legacy_mask_irq(irq);
}

static void tegra_unmask(unsigned int irq)
{
	gic_unmask_irq(irq);
	tegra_legacy_unmask_irq(irq);
}

static int tegra_set_wake(unsigned int irq, unsigned int enable)
{
	int ret;
	ret = tegra_set_lp1_wake(irq, enable);
	if (ret)
		return ret;

	if (tegra_get_suspend_mode() == TEGRA_SUSPEND_LP0)
		return tegra_set_lp0_wake(irq, enable);

	return 0;
}

static int tegra_set_type(unsigned int irq, unsigned int flow_type)
{
	return tegra_set_lp0_wake_type(irq, flow_type);
}

static void tegra_ack(unsigned int irq)
{
	tegra_legacy_force_irq_clr(irq);
	gic_ack_irq(irq);
}

static int tegra_retrigger(unsigned int irq)
{
	tegra_legacy_force_irq_set(irq);
	return 1;
}

static struct irq_chip tegra_irq = {
	.name		= "PPI",
	.ack		= tegra_ack,
	.mask		= tegra_mask,
	.unmask		= tegra_unmask,
	.set_wake	= tegra_set_wake,
	.set_type	= tegra_set_type,
#ifdef CONFIG_SMP
	.set_affinity	= gic_set_cpu,
#endif
	.retrigger	= tegra_retrigger,
};

void __init tegra_init_irq(void)
{
	unsigned int i;
	int irq;

	tegra_init_legacy_irq();

	gic_dist_init(0, IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE), 29);
	gic_cpu_init(0, IO_ADDRESS(TEGRA_ARM_PERIF_BASE + 0x100));

	for (i = 0; i < INT_MAIN_NR; i++) {
		irq = INT_PRI_BASE + i;
		set_irq_chip(irq, &tegra_irq);
		set_irq_handler(irq, handle_level_irq);
		set_irq_flags(irq, IRQF_VALID);
	}
}

#ifdef CONFIG_PM
void tegra_irq_suspend(void)
{
	tegra_legacy_irq_suspend();
}

void tegra_irq_resume(void)
{
	tegra_legacy_irq_resume();
	tegra_irq_handle_wake();
}
#endif

#ifndef CONFIG_ARCH_TEGRA_2x_SOC

static u32 gic_affinity[INT_GIC_NR/4];

void tegra_irq_disable_affinity(void)
{
	void __iomem *gic_base = IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE);
	unsigned int i;

	BUG_ON(is_lp_cluster());

       /* The GIC distributor TARGET register is one byte per IRQ. */
	for (i = 32; i < INT_GIC_NR; i += 4) {
		/* Save the affinity. */
		gic_affinity[i/4] = __raw_readl(gic_base + GIC_DIST_TARGET + i);

		/* Force this interrupt to CPU0. */
		__raw_writel(0x01010101, gic_base + GIC_DIST_TARGET + i);
	}

       wmb();
}

void tegra_irq_restore_affinity(void)
{
	void __iomem *gic_base = IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE);
	unsigned int i;

	BUG_ON(is_lp_cluster());

       /* The GIC distributor TARGET register is one byte per IRQ. */
	for (i = 32; i < INT_GIC_NR; i += 4) {
#ifdef CONFIG_BUG
		u32 reg = __raw_readl(gic_base + GIC_DIST_TARGET + i);
		if (reg & 0xFEFEFEFE)
			panic("GIC affinity changed!");
#endif
		/* Restore this interrupt's affinity. */
		__raw_writel(gic_affinity[i/4], gic_base + GIC_DIST_TARGET + i);
	}

       wmb();
}

void tegra_irq_affinity_to_cpu0(void)
{
	void __iomem *gic_base = IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE);
	unsigned int i;

	BUG_ON(is_lp_cluster());

	for (i = 32; i < INT_GIC_NR; i += 4)
		__raw_writel(0x01010101, gic_base + GIC_DIST_TARGET + i);
       wmb();
}

void tegra_irq_pass_through_disable(void)
{
	void __iomem *base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE + 0x100);
	u32 val = readl(base + GIC_CPU_CTRL);
	val |= 2; /* enableNS = disable pass through */
	writel(1, base + GIC_CPU_CTRL);
}
#endif

#ifdef CONFIG_DEBUG_FS
static int tegra_wake_irq_debug_show(struct seq_file *s, void *data)
{
	int wake;
	int irq;
	struct irq_desc *desc;
	const char *irq_name;

	seq_printf(s, "wake  irq  count  name\n");
	seq_printf(s, "----------------------\n");
	for (wake = 0; wake < 32; wake++) {
		irq = tegra_wake_to_irq(wake);
		if (irq < 0)
			continue;

		desc = irq_to_desc(irq);
		if (tegra_wake_irq_count[wake] == 0 && desc->action == NULL)
			continue;

		if (!(desc->status & IRQ_WAKEUP))
			continue;

		irq_name = (desc->action && desc->action->name) ?
			desc->action->name : "???";

		seq_printf(s, "%4d  %3d  %5d  %s\n",
			wake, irq, tegra_wake_irq_count[wake], irq_name);
	}
	return 0;
}

static int tegra_wake_irq_debug_open(struct inode *inode, struct file *file)
{
	return single_open(file, tegra_wake_irq_debug_show, NULL);
}

static const struct file_operations tegra_wake_irq_debug_fops = {
	.open		= tegra_wake_irq_debug_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int __init tegra_irq_debug_init(void)
{
	struct dentry *d;

	d = debugfs_create_file("wake_irq", 0755, NULL, NULL,
		&tegra_wake_irq_debug_fops);
	if (!d) {
		pr_info("Failed to create suspend_mode debug file\n");
		return -ENOMEM;
	}

	return 0;
}

late_initcall(tegra_irq_debug_init);
#endif