arch/arm/mach-omap2/omap-wakeupgen.c - kernel/mindspeed - Git at Google

 /*
  * OMAP WakeupGen Source file
  *
  * OMAP WakeupGen is the interrupt controller extension used along
  * with ARM GIC to wake the CPU out from low power states on
  * external interrupts. It is responsible for generating wakeup
  * event from the incoming interrupts and enable bits. It is
  * implemented in MPU always ON power domain. During normal operation,
  * WakeupGen delivers external interrupts directly to the GIC.
  *
  * Copyright (C) 2011 Texas Instruments, Inc.
  *	Santosh Shilimkar <santosh.shilimkar@ti.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/of_address.h>
 #include <linux/platform_device.h>
 #include <linux/cpu.h>
 #include <linux/notifier.h>
 #include <linux/cpu_pm.h>

 #include "omap-wakeupgen.h"
 #include "omap-secure.h"

 #include "soc.h"
 #include "omap4-sar-layout.h"
 #include "common.h"
 #include "pm.h"

 #define AM43XX_NR_REG_BANKS	7
 #define AM43XX_IRQS		224
 #define MAX_NR_REG_BANKS	AM43XX_NR_REG_BANKS
 #define MAX_IRQS		AM43XX_IRQS
 #define DEFAULT_NR_REG_BANKS	5
 #define DEFAULT_IRQS		160
 #define WKG_MASK_ALL		0x00000000
 #define WKG_UNMASK_ALL		0xffffffff
 #define CPU_ENA_OFFSET		0x400
 #define CPU0_ID			0x0
 #define CPU1_ID			0x1
 #define OMAP4_NR_BANKS		4
 #define OMAP4_NR_IRQS		128

 static void __iomem *wakeupgen_base;
 static void __iomem *sar_base;
 static DEFINE_RAW_SPINLOCK(wakeupgen_lock);
 static unsigned int irq_target_cpu[MAX_IRQS];
 static unsigned int irq_banks = DEFAULT_NR_REG_BANKS;
 static unsigned int max_irqs = DEFAULT_IRQS;
 static unsigned int omap_secure_apis;

 /*
  * Static helper functions.
  */
 static inline u32 wakeupgen_readl(u8 idx, u32 cpu)
 {
 	return readl_relaxed(wakeupgen_base + OMAP_WKG_ENB_A_0 +
 				(cpu * CPU_ENA_OFFSET) + (idx * 4));
 }

 static inline void wakeupgen_writel(u32 val, u8 idx, u32 cpu)
 {
 	writel_relaxed(val, wakeupgen_base + OMAP_WKG_ENB_A_0 +
 				(cpu * CPU_ENA_OFFSET) + (idx * 4));
 }

 static inline void sar_writel(u32 val, u32 offset, u8 idx)
 {
 	writel_relaxed(val, sar_base + offset + (idx * 4));
 }

 static inline int _wakeupgen_get_irq_info(u32 irq, u32 *bit_posn, u8 *reg_index)
 {
 	/*
 	 * Each WakeupGen register controls 32 interrupt.
 	 * i.e. 1 bit per SPI IRQ
 	 */
 	*reg_index = irq >> 5;
 	*bit_posn = irq %= 32;

 	return 0;
 }

 static void _wakeupgen_clear(unsigned int irq, unsigned int cpu)
 {
 	u32 val, bit_number;
 	u8 i;

 	if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
 		return;

 	val = wakeupgen_readl(i, cpu);
 	val &= ~BIT(bit_number);
 	wakeupgen_writel(val, i, cpu);
 }

 static void _wakeupgen_set(unsigned int irq, unsigned int cpu)
 {
 	u32 val, bit_number;
 	u8 i;

 	if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
 		return;

 	val = wakeupgen_readl(i, cpu);
 	val |= BIT(bit_number);
 	wakeupgen_writel(val, i, cpu);
 }

 /*
  * Architecture specific Mask extension
  */
 static void wakeupgen_mask(struct irq_data *d)
 {
 	unsigned long flags;

 	raw_spin_lock_irqsave(&wakeupgen_lock, flags);
 	_wakeupgen_clear(d->hwirq, irq_target_cpu[d->hwirq]);
 	raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
 	irq_chip_mask_parent(d);
 }

 /*
  * Architecture specific Unmask extension
  */
 static void wakeupgen_unmask(struct irq_data *d)
 {
 	unsigned long flags;

 	raw_spin_lock_irqsave(&wakeupgen_lock, flags);
 	_wakeupgen_set(d->hwirq, irq_target_cpu[d->hwirq]);
 	raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
 	irq_chip_unmask_parent(d);
 }

 #ifdef CONFIG_HOTPLUG_CPU
 static DEFINE_PER_CPU(u32 [MAX_NR_REG_BANKS], irqmasks);

 static void _wakeupgen_save_masks(unsigned int cpu)
 {
 	u8 i;

 	for (i = 0; i < irq_banks; i++)
 		per_cpu(irqmasks, cpu)[i] = wakeupgen_readl(i, cpu);
 }

 static void _wakeupgen_restore_masks(unsigned int cpu)
 {
 	u8 i;

 	for (i = 0; i < irq_banks; i++)
 		wakeupgen_writel(per_cpu(irqmasks, cpu)[i], i, cpu);
 }

 static void _wakeupgen_set_all(unsigned int cpu, unsigned int reg)
 {
 	u8 i;

 	for (i = 0; i < irq_banks; i++)
 		wakeupgen_writel(reg, i, cpu);
 }

 /*
  * Mask or unmask all interrupts on given CPU.
  *	0 = Mask all interrupts on the 'cpu'
  *	1 = Unmask all interrupts on the 'cpu'
  * Ensure that the initial mask is maintained. This is faster than
  * iterating through GIC registers to arrive at the correct masks.
  */
 static void wakeupgen_irqmask_all(unsigned int cpu, unsigned int set)
 {
 	unsigned long flags;

 	raw_spin_lock_irqsave(&wakeupgen_lock, flags);
 	if (set) {
 		_wakeupgen_save_masks(cpu);
 		_wakeupgen_set_all(cpu, WKG_MASK_ALL);
 	} else {
 		_wakeupgen_set_all(cpu, WKG_UNMASK_ALL);
 		_wakeupgen_restore_masks(cpu);
 	}
 	raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
 }
 #endif

 #ifdef CONFIG_CPU_PM
 static inline void omap4_irq_save_context(void)
 {
 	u32 i, val;

 	if (omap_rev() == OMAP4430_REV_ES1_0)
 		return;

 	for (i = 0; i < irq_banks; i++) {
 		/* Save the CPUx interrupt mask for IRQ 0 to 127 */
 		val = wakeupgen_readl(i, 0);
 		sar_writel(val, WAKEUPGENENB_OFFSET_CPU0, i);
 		val = wakeupgen_readl(i, 1);
 		sar_writel(val, WAKEUPGENENB_OFFSET_CPU1, i);

 		/*
 		 * Disable the secure interrupts for CPUx. The restore
 		 * code blindly restores secure and non-secure interrupt
 		 * masks from SAR RAM. Secure interrupts are not suppose
 		 * to be enabled from HLOS. So overwrite the SAR location
 		 * so that the secure interrupt remains disabled.
 		 */
 		sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
 		sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
 	}

 	/* Save AuxBoot* registers */
 	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
 	writel_relaxed(val, sar_base + AUXCOREBOOT0_OFFSET);
 	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_1);
 	writel_relaxed(val, sar_base + AUXCOREBOOT1_OFFSET);

 	/* Save SyncReq generation logic */
 	val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_MASK);
 	writel_relaxed(val, sar_base + PTMSYNCREQ_MASK_OFFSET);
 	val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_EN);
 	writel_relaxed(val, sar_base + PTMSYNCREQ_EN_OFFSET);

 	/* Set the Backup Bit Mask status */
 	val = readl_relaxed(sar_base + SAR_BACKUP_STATUS_OFFSET);
 	val |= SAR_BACKUP_STATUS_WAKEUPGEN;
 	writel_relaxed(val, sar_base + SAR_BACKUP_STATUS_OFFSET);

 }

 static inline void omap5_irq_save_context(void)
 {
 	u32 i, val;

 	for (i = 0; i < irq_banks; i++) {
 		/* Save the CPUx interrupt mask for IRQ 0 to 159 */
 		val = wakeupgen_readl(i, 0);
 		sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU0, i);
 		val = wakeupgen_readl(i, 1);
 		sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU1, i);
 		sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
 		sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
 	}

 	/* Save AuxBoot* registers */
 	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
 	writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT0_OFFSET);
 	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
 	writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT1_OFFSET);

 	/* Set the Backup Bit Mask status */
 	val = readl_relaxed(sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);
 	val |= SAR_BACKUP_STATUS_WAKEUPGEN;
 	writel_relaxed(val, sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);

 }

 /*
  * Save WakeupGen interrupt context in SAR BANK3. Restore is done by
  * ROM code. WakeupGen IP is integrated along with GIC to manage the
  * interrupt wakeups from CPU low power states. It manages
  * masking/unmasking of Shared peripheral interrupts(SPI). So the
  * interrupt enable/disable control should be in sync and consistent
  * at WakeupGen and GIC so that interrupts are not lost.
  */
 static void irq_save_context(void)
 {
 	if (!sar_base)
 		sar_base = omap4_get_sar_ram_base();

 	if (soc_is_omap54xx())
 		omap5_irq_save_context();
 	else
 		omap4_irq_save_context();
 }

 /*
  * Clear WakeupGen SAR backup status.
  */
 static void irq_sar_clear(void)
 {
 	u32 val;
 	u32 offset = SAR_BACKUP_STATUS_OFFSET;

 	if (soc_is_omap54xx())
 		offset = OMAP5_SAR_BACKUP_STATUS_OFFSET;

 	val = readl_relaxed(sar_base + offset);
 	val &= ~SAR_BACKUP_STATUS_WAKEUPGEN;
 	writel_relaxed(val, sar_base + offset);
 }

 /*
  * Save GIC and Wakeupgen interrupt context using secure API
  * for HS/EMU devices.
  */
 static void irq_save_secure_context(void)
 {
 	u32 ret;
 	ret = omap_secure_dispatcher(OMAP4_HAL_SAVEGIC_INDEX,
 				FLAG_START_CRITICAL,
 				0, 0, 0, 0, 0);
 	if (ret != API_HAL_RET_VALUE_OK)
 		pr_err("GIC and Wakeupgen context save failed\n");
 }
 #endif

 #ifdef CONFIG_HOTPLUG_CPU
 static int irq_cpu_hotplug_notify(struct notifier_block *self,
 				  unsigned long action, void *hcpu)
 {
 	unsigned int cpu = (unsigned int)hcpu;

 	switch (action) {
 	case CPU_ONLINE:
 		wakeupgen_irqmask_all(cpu, 0);
 		break;
 	case CPU_DEAD:
 		wakeupgen_irqmask_all(cpu, 1);
 		break;
 	}
 	return NOTIFY_OK;
 }

 static struct notifier_block __refdata irq_hotplug_notifier = {
 	.notifier_call = irq_cpu_hotplug_notify,
 };

 static void __init irq_hotplug_init(void)
 {
 	register_hotcpu_notifier(&irq_hotplug_notifier);
 }
 #else
 static void __init irq_hotplug_init(void)
 {}
 #endif

 #ifdef CONFIG_CPU_PM
 static int irq_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
 {
 	switch (cmd) {
 	case CPU_CLUSTER_PM_ENTER:
 		if (omap_type() == OMAP2_DEVICE_TYPE_GP)
 			irq_save_context();
 		else
 			irq_save_secure_context();
 		break;
 	case CPU_CLUSTER_PM_EXIT:
 		if (omap_type() == OMAP2_DEVICE_TYPE_GP)
 			irq_sar_clear();
 		break;
 	}
 	return NOTIFY_OK;
 }

 static struct notifier_block irq_notifier_block = {
 	.notifier_call = irq_notifier,
 };

 static void __init irq_pm_init(void)
 {
 	/* FIXME: Remove this when MPU OSWR support is added */
 	if (!IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE))
 		cpu_pm_register_notifier(&irq_notifier_block);
 }
 #else
 static void __init irq_pm_init(void)
 {}
 #endif

 void __iomem *omap_get_wakeupgen_base(void)
 {
 	return wakeupgen_base;
 }

 int omap_secure_apis_support(void)
 {
 	return omap_secure_apis;
 }

 static struct irq_chip wakeupgen_chip = {
 	.name			= "WUGEN",
 	.irq_eoi		= irq_chip_eoi_parent,
 	.irq_mask		= wakeupgen_mask,
 	.irq_unmask		= wakeupgen_unmask,
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_set_type		= irq_chip_set_type_parent,
 	.flags			= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND,
 #ifdef CONFIG_SMP
 	.irq_set_affinity	= irq_chip_set_affinity_parent,
 #endif
 };

 static int wakeupgen_domain_xlate(struct irq_domain *domain,
 				  struct device_node *controller,
 				  const u32 *intspec,
 				  unsigned int intsize,
 				  unsigned long *out_hwirq,
 				  unsigned int *out_type)
 {
 	if (domain->of_node != controller)
 		return -EINVAL;	/* Shouldn't happen, really... */
 	if (intsize != 3)
 		return -EINVAL;	/* Not GIC compliant */
 	if (intspec[0] != 0)
 		return -EINVAL;	/* No PPI should point to this domain */

 	*out_hwirq = intspec[1];
 	*out_type = intspec[2];
 	return 0;
 }

 static int wakeupgen_domain_alloc(struct irq_domain *domain,
 				  unsigned int virq,
 				  unsigned int nr_irqs, void *data)
 {
 	struct of_phandle_args *args = data;
 	struct of_phandle_args parent_args;
 	irq_hw_number_t hwirq;
 	int i;

 	if (args->args_count != 3)
 		return -EINVAL;	/* Not GIC compliant */
 	if (args->args[0] != 0)
 		return -EINVAL;	/* No PPI should point to this domain */

 	hwirq = args->args[1];
 	if (hwirq >= MAX_IRQS)
 		return -EINVAL;	/* Can't deal with this */

 	for (i = 0; i < nr_irqs; i++)
 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 					      &wakeupgen_chip, NULL);

 	parent_args = *args;
 	parent_args.np = domain->parent->of_node;
 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &parent_args);
 }

 static struct irq_domain_ops wakeupgen_domain_ops = {
 	.xlate	= wakeupgen_domain_xlate,
 	.alloc	= wakeupgen_domain_alloc,
 	.free	= irq_domain_free_irqs_common,
 };

 /*
  * Initialise the wakeupgen module.
  */
 static int __init wakeupgen_init(struct device_node *node,
 				 struct device_node *parent)
 {
 	struct irq_domain *parent_domain, *domain;
 	int i;
 	unsigned int boot_cpu = smp_processor_id();
 	u32 val;

 	if (!parent) {
 		pr_err("%s: no parent, giving up\n", node->full_name);
 		return -ENODEV;
 	}

 	parent_domain = irq_find_host(parent);
 	if (!parent_domain) {
 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
 		return -ENXIO;
 	}
 	/* Not supported on OMAP4 ES1.0 silicon */
 	if (omap_rev() == OMAP4430_REV_ES1_0) {
 		WARN(1, "WakeupGen: Not supported on OMAP4430 ES1.0\n");
 		return -EPERM;
 	}

 	/* Static mapping, never released */
 	wakeupgen_base = of_iomap(node, 0);
 	if (WARN_ON(!wakeupgen_base))
 		return -ENOMEM;

 	if (cpu_is_omap44xx()) {
 		irq_banks = OMAP4_NR_BANKS;
 		max_irqs = OMAP4_NR_IRQS;
 		omap_secure_apis = 1;
 	} else if (soc_is_am43xx()) {
 		irq_banks = AM43XX_NR_REG_BANKS;
 		max_irqs = AM43XX_IRQS;
 	}

 	domain = irq_domain_add_hierarchy(parent_domain, 0, max_irqs,
 					  node, &wakeupgen_domain_ops,
 					  NULL);
 	if (!domain) {
 		iounmap(wakeupgen_base);
 		return -ENOMEM;
 	}

 	/* Clear all IRQ bitmasks at wakeupGen level */
 	for (i = 0; i < irq_banks; i++) {
 		wakeupgen_writel(0, i, CPU0_ID);
 		if (!soc_is_am43xx())
 			wakeupgen_writel(0, i, CPU1_ID);
 	}

 	/*
 	 * FIXME: Add support to set_smp_affinity() once the core
 	 * GIC code has necessary hooks in place.
 	 */

 	/* Associate all the IRQs to boot CPU like GIC init does. */
 	for (i = 0; i < max_irqs; i++)
 		irq_target_cpu[i] = boot_cpu;

 	/*
 	 * Enables OMAP5 ES2 PM Mode using ES2_PM_MODE in AMBA_IF_MODE
 	 * 0x0:	ES1 behavior, CPU cores would enter and exit OFF mode together.
 	 * 0x1:	ES2 behavior, CPU cores are allowed to enter/exit OFF mode
 	 * independently.
 	 * This needs to be set one time thanks to always ON domain.
 	 *
 	 * We do not support ES1 behavior anymore. OMAP5 is assumed to be
 	 * ES2.0, and the same is applicable for DRA7.
 	 */
 	if (soc_is_omap54xx() || soc_is_dra7xx()) {
 		val = __raw_readl(wakeupgen_base + OMAP_AMBA_IF_MODE);
 		val |= BIT(5);
 		omap_smc1(OMAP5_MON_AMBA_IF_INDEX, val);
 	}

 	irq_hotplug_init();
 	irq_pm_init();

 	return 0;
 }

 /*
  * We cannot use the IRQCHIP_DECLARE macro that lives in
  * drivers/irqchip, so we're forced to roll our own. Not very nice.
  */
 OF_DECLARE_2(irqchip, ti_wakeupgen, "ti,omap4-wugen-mpu", wakeupgen_init);
	/*
	* OMAP WakeupGen Source file
	*
	* OMAP WakeupGen is the interrupt controller extension used along
	* with ARM GIC to wake the CPU out from low power states on
	* external interrupts. It is responsible for generating wakeup
	* event from the incoming interrupts and enable bits. It is
	* implemented in MPU always ON power domain. During normal operation,
	* WakeupGen delivers external interrupts directly to the GIC.
	*
	* Copyright (C) 2011 Texas Instruments, Inc.
	* Santosh Shilimkar <santosh.shilimkar@ti.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/io.h>
	#include <linux/irq.h>
	#include <linux/irqdomain.h>
	#include <linux/of_address.h>
	#include <linux/platform_device.h>
	#include <linux/cpu.h>
	#include <linux/notifier.h>
	#include <linux/cpu_pm.h>

	#include "omap-wakeupgen.h"
	#include "omap-secure.h"

	#include "soc.h"
	#include "omap4-sar-layout.h"
	#include "common.h"
	#include "pm.h"

	#define AM43XX_NR_REG_BANKS 7
	#define AM43XX_IRQS 224
	#define MAX_NR_REG_BANKS AM43XX_NR_REG_BANKS
	#define MAX_IRQS AM43XX_IRQS
	#define DEFAULT_NR_REG_BANKS 5
	#define DEFAULT_IRQS 160
	#define WKG_MASK_ALL 0x00000000
	#define WKG_UNMASK_ALL 0xffffffff
	#define CPU_ENA_OFFSET 0x400
	#define CPU0_ID 0x0
	#define CPU1_ID 0x1
	#define OMAP4_NR_BANKS 4
	#define OMAP4_NR_IRQS 128

	static void __iomem *wakeupgen_base;
	static void __iomem *sar_base;
	static DEFINE_RAW_SPINLOCK(wakeupgen_lock);
	static unsigned int irq_target_cpu[MAX_IRQS];
	static unsigned int irq_banks = DEFAULT_NR_REG_BANKS;
	static unsigned int max_irqs = DEFAULT_IRQS;
	static unsigned int omap_secure_apis;

	/*
	* Static helper functions.
	*/
	static inline u32 wakeupgen_readl(u8 idx, u32 cpu)
	{
	return readl_relaxed(wakeupgen_base + OMAP_WKG_ENB_A_0 +
	(cpu * CPU_ENA_OFFSET) + (idx * 4));
	}

	static inline void wakeupgen_writel(u32 val, u8 idx, u32 cpu)
	{
	writel_relaxed(val, wakeupgen_base + OMAP_WKG_ENB_A_0 +
	(cpu * CPU_ENA_OFFSET) + (idx * 4));
	}

	static inline void sar_writel(u32 val, u32 offset, u8 idx)
	{
	writel_relaxed(val, sar_base + offset + (idx * 4));
	}

	static inline int _wakeupgen_get_irq_info(u32 irq, u32 bit_posn, u8 reg_index)
	{
	/*
	* Each WakeupGen register controls 32 interrupt.
	* i.e. 1 bit per SPI IRQ
	*/
	*reg_index = irq >> 5;
	*bit_posn = irq %= 32;

	return 0;
	}

	static void _wakeupgen_clear(unsigned int irq, unsigned int cpu)
	{
	u32 val, bit_number;
	u8 i;

	if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
	return;

	val = wakeupgen_readl(i, cpu);
	val &= ~BIT(bit_number);
	wakeupgen_writel(val, i, cpu);
	}

	static void _wakeupgen_set(unsigned int irq, unsigned int cpu)
	{
	u32 val, bit_number;
	u8 i;

	if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
	return;

	val = wakeupgen_readl(i, cpu);
	val \|= BIT(bit_number);
	wakeupgen_writel(val, i, cpu);
	}

	/*
	* Architecture specific Mask extension
	*/
	static void wakeupgen_mask(struct irq_data *d)
	{
	unsigned long flags;

	raw_spin_lock_irqsave(&wakeupgen_lock, flags);
	_wakeupgen_clear(d->hwirq, irq_target_cpu[d->hwirq]);
	raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
	irq_chip_mask_parent(d);
	}

	/*
	* Architecture specific Unmask extension
	*/
	static void wakeupgen_unmask(struct irq_data *d)
	{
	unsigned long flags;

	raw_spin_lock_irqsave(&wakeupgen_lock, flags);
	_wakeupgen_set(d->hwirq, irq_target_cpu[d->hwirq]);
	raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
	irq_chip_unmask_parent(d);
	}

	#ifdef CONFIG_HOTPLUG_CPU
	static DEFINE_PER_CPU(u32 [MAX_NR_REG_BANKS], irqmasks);

	static void _wakeupgen_save_masks(unsigned int cpu)
	{
	u8 i;

	for (i = 0; i < irq_banks; i++)
	per_cpu(irqmasks, cpu)[i] = wakeupgen_readl(i, cpu);
	}

	static void _wakeupgen_restore_masks(unsigned int cpu)
	{
	u8 i;

	for (i = 0; i < irq_banks; i++)
	wakeupgen_writel(per_cpu(irqmasks, cpu)[i], i, cpu);
	}

	static void _wakeupgen_set_all(unsigned int cpu, unsigned int reg)
	{
	u8 i;

	for (i = 0; i < irq_banks; i++)
	wakeupgen_writel(reg, i, cpu);
	}

	/*
	* Mask or unmask all interrupts on given CPU.
	* 0 = Mask all interrupts on the 'cpu'
	* 1 = Unmask all interrupts on the 'cpu'
	* Ensure that the initial mask is maintained. This is faster than
	* iterating through GIC registers to arrive at the correct masks.
	*/
	static void wakeupgen_irqmask_all(unsigned int cpu, unsigned int set)
	{
	unsigned long flags;

	raw_spin_lock_irqsave(&wakeupgen_lock, flags);
	if (set) {
	_wakeupgen_save_masks(cpu);
	_wakeupgen_set_all(cpu, WKG_MASK_ALL);
	} else {
	_wakeupgen_set_all(cpu, WKG_UNMASK_ALL);
	_wakeupgen_restore_masks(cpu);
	}
	raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
	}
	#endif

	#ifdef CONFIG_CPU_PM
	static inline void omap4_irq_save_context(void)
	{
	u32 i, val;

	if (omap_rev() == OMAP4430_REV_ES1_0)
	return;

	for (i = 0; i < irq_banks; i++) {
	/* Save the CPUx interrupt mask for IRQ 0 to 127 */
	val = wakeupgen_readl(i, 0);
	sar_writel(val, WAKEUPGENENB_OFFSET_CPU0, i);
	val = wakeupgen_readl(i, 1);
	sar_writel(val, WAKEUPGENENB_OFFSET_CPU1, i);

	/*
	* Disable the secure interrupts for CPUx. The restore
	* code blindly restores secure and non-secure interrupt
	* masks from SAR RAM. Secure interrupts are not suppose
	* to be enabled from HLOS. So overwrite the SAR location
	* so that the secure interrupt remains disabled.
	*/
	sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
	sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
	}

	/* Save AuxBoot* registers */
	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
	writel_relaxed(val, sar_base + AUXCOREBOOT0_OFFSET);
	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_1);
	writel_relaxed(val, sar_base + AUXCOREBOOT1_OFFSET);

	/* Save SyncReq generation logic */
	val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_MASK);
	writel_relaxed(val, sar_base + PTMSYNCREQ_MASK_OFFSET);
	val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_EN);
	writel_relaxed(val, sar_base + PTMSYNCREQ_EN_OFFSET);

	/* Set the Backup Bit Mask status */
	val = readl_relaxed(sar_base + SAR_BACKUP_STATUS_OFFSET);
	val \|= SAR_BACKUP_STATUS_WAKEUPGEN;
	writel_relaxed(val, sar_base + SAR_BACKUP_STATUS_OFFSET);

	}

	static inline void omap5_irq_save_context(void)
	{
	u32 i, val;

	for (i = 0; i < irq_banks; i++) {
	/* Save the CPUx interrupt mask for IRQ 0 to 159 */
	val = wakeupgen_readl(i, 0);
	sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU0, i);
	val = wakeupgen_readl(i, 1);
	sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU1, i);
	sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
	sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
	}

	/* Save AuxBoot* registers */
	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
	writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT0_OFFSET);
	val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
	writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT1_OFFSET);

	/* Set the Backup Bit Mask status */
	val = readl_relaxed(sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);
	val \|= SAR_BACKUP_STATUS_WAKEUPGEN;
	writel_relaxed(val, sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);

	}

	/*
	* Save WakeupGen interrupt context in SAR BANK3. Restore is done by
	* ROM code. WakeupGen IP is integrated along with GIC to manage the
	* interrupt wakeups from CPU low power states. It manages
	* masking/unmasking of Shared peripheral interrupts(SPI). So the
	* interrupt enable/disable control should be in sync and consistent
	* at WakeupGen and GIC so that interrupts are not lost.
	*/
	static void irq_save_context(void)
	{
	if (!sar_base)
	sar_base = omap4_get_sar_ram_base();

	if (soc_is_omap54xx())
	omap5_irq_save_context();
	else
	omap4_irq_save_context();
	}

	/*
	* Clear WakeupGen SAR backup status.
	*/
	static void irq_sar_clear(void)
	{
	u32 val;
	u32 offset = SAR_BACKUP_STATUS_OFFSET;

	if (soc_is_omap54xx())
	offset = OMAP5_SAR_BACKUP_STATUS_OFFSET;

	val = readl_relaxed(sar_base + offset);
	val &= ~SAR_BACKUP_STATUS_WAKEUPGEN;
	writel_relaxed(val, sar_base + offset);
	}

	/*
	* Save GIC and Wakeupgen interrupt context using secure API
	* for HS/EMU devices.
	*/
	static void irq_save_secure_context(void)
	{
	u32 ret;
	ret = omap_secure_dispatcher(OMAP4_HAL_SAVEGIC_INDEX,
	FLAG_START_CRITICAL,
	0, 0, 0, 0, 0);
	if (ret != API_HAL_RET_VALUE_OK)
	pr_err("GIC and Wakeupgen context save failed\n");
	}
	#endif

	#ifdef CONFIG_HOTPLUG_CPU
	static int irq_cpu_hotplug_notify(struct notifier_block *self,
	unsigned long action, void *hcpu)
	{
	unsigned int cpu = (unsigned int)hcpu;

	switch (action) {
	case CPU_ONLINE:
	wakeupgen_irqmask_all(cpu, 0);
	break;
	case CPU_DEAD:
	wakeupgen_irqmask_all(cpu, 1);
	break;
	}
	return NOTIFY_OK;
	}

	static struct notifier_block __refdata irq_hotplug_notifier = {
	.notifier_call = irq_cpu_hotplug_notify,
	};

	static void __init irq_hotplug_init(void)
	{
	register_hotcpu_notifier(&irq_hotplug_notifier);
	}
	#else
	static void __init irq_hotplug_init(void)
	{}
	#endif

	#ifdef CONFIG_CPU_PM
	static int irq_notifier(struct notifier_block self, unsigned long cmd, void v)
	{
	switch (cmd) {
	case CPU_CLUSTER_PM_ENTER:
	if (omap_type() == OMAP2_DEVICE_TYPE_GP)
	irq_save_context();
	else
	irq_save_secure_context();
	break;
	case CPU_CLUSTER_PM_EXIT:
	if (omap_type() == OMAP2_DEVICE_TYPE_GP)
	irq_sar_clear();
	break;
	}
	return NOTIFY_OK;
	}

	static struct notifier_block irq_notifier_block = {
	.notifier_call = irq_notifier,
	};

	static void __init irq_pm_init(void)
	{
	/* FIXME: Remove this when MPU OSWR support is added */
	if (!IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE))
	cpu_pm_register_notifier(&irq_notifier_block);
	}
	#else
	static void __init irq_pm_init(void)
	{}
	#endif

	void __iomem *omap_get_wakeupgen_base(void)
	{
	return wakeupgen_base;
	}

	int omap_secure_apis_support(void)
	{
	return omap_secure_apis;
	}

	static struct irq_chip wakeupgen_chip = {
	.name = "WUGEN",
	.irq_eoi = irq_chip_eoi_parent,
	.irq_mask = wakeupgen_mask,
	.irq_unmask = wakeupgen_unmask,
	.irq_retrigger = irq_chip_retrigger_hierarchy,
	.irq_set_type = irq_chip_set_type_parent,
	.flags = IRQCHIP_SKIP_SET_WAKE \| IRQCHIP_MASK_ON_SUSPEND,
	#ifdef CONFIG_SMP
	.irq_set_affinity = irq_chip_set_affinity_parent,
	#endif
	};

	static int wakeupgen_domain_xlate(struct irq_domain *domain,
	struct device_node *controller,
	const u32 *intspec,
	unsigned int intsize,
	unsigned long *out_hwirq,
	unsigned int *out_type)
	{
	if (domain->of_node != controller)
	return -EINVAL; /* Shouldn't happen, really... */
	if (intsize != 3)
	return -EINVAL; /* Not GIC compliant */
	if (intspec[0] != 0)
	return -EINVAL; /* No PPI should point to this domain */

	*out_hwirq = intspec[1];
	*out_type = intspec[2];
	return 0;
	}

	static int wakeupgen_domain_alloc(struct irq_domain *domain,
	unsigned int virq,
	unsigned int nr_irqs, void *data)
	{
	struct of_phandle_args *args = data;
	struct of_phandle_args parent_args;
	irq_hw_number_t hwirq;
	int i;

	if (args->args_count != 3)
	return -EINVAL; /* Not GIC compliant */
	if (args->args[0] != 0)
	return -EINVAL; /* No PPI should point to this domain */

	hwirq = args->args[1];
	if (hwirq >= MAX_IRQS)
	return -EINVAL; /* Can't deal with this */

	for (i = 0; i < nr_irqs; i++)
	irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
	&wakeupgen_chip, NULL);

	parent_args = *args;
	parent_args.np = domain->parent->of_node;
	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &parent_args);
	}

	static struct irq_domain_ops wakeupgen_domain_ops = {
	.xlate = wakeupgen_domain_xlate,
	.alloc = wakeupgen_domain_alloc,
	.free = irq_domain_free_irqs_common,
	};

	/*
	* Initialise the wakeupgen module.
	*/
	static int __init wakeupgen_init(struct device_node *node,
	struct device_node *parent)
	{
	struct irq_domain parent_domain, domain;
	int i;
	unsigned int boot_cpu = smp_processor_id();
	u32 val;

	if (!parent) {
	pr_err("%s: no parent, giving up\n", node->full_name);
	return -ENODEV;
	}

	parent_domain = irq_find_host(parent);
	if (!parent_domain) {
	pr_err("%s: unable to obtain parent domain\n", node->full_name);
	return -ENXIO;
	}
	/* Not supported on OMAP4 ES1.0 silicon */
	if (omap_rev() == OMAP4430_REV_ES1_0) {
	WARN(1, "WakeupGen: Not supported on OMAP4430 ES1.0\n");
	return -EPERM;
	}

	/* Static mapping, never released */
	wakeupgen_base = of_iomap(node, 0);
	if (WARN_ON(!wakeupgen_base))
	return -ENOMEM;

	if (cpu_is_omap44xx()) {
	irq_banks = OMAP4_NR_BANKS;
	max_irqs = OMAP4_NR_IRQS;
	omap_secure_apis = 1;
	} else if (soc_is_am43xx()) {
	irq_banks = AM43XX_NR_REG_BANKS;
	max_irqs = AM43XX_IRQS;
	}

	domain = irq_domain_add_hierarchy(parent_domain, 0, max_irqs,
	node, &wakeupgen_domain_ops,
	NULL);
	if (!domain) {
	iounmap(wakeupgen_base);
	return -ENOMEM;
	}

	/* Clear all IRQ bitmasks at wakeupGen level */
	for (i = 0; i < irq_banks; i++) {
	wakeupgen_writel(0, i, CPU0_ID);
	if (!soc_is_am43xx())
	wakeupgen_writel(0, i, CPU1_ID);
	}

	/*
	* FIXME: Add support to set_smp_affinity() once the core
	* GIC code has necessary hooks in place.
	*/

	/* Associate all the IRQs to boot CPU like GIC init does. */
	for (i = 0; i < max_irqs; i++)
	irq_target_cpu[i] = boot_cpu;

	/*
	* Enables OMAP5 ES2 PM Mode using ES2_PM_MODE in AMBA_IF_MODE
	* 0x0: ES1 behavior, CPU cores would enter and exit OFF mode together.
	* 0x1: ES2 behavior, CPU cores are allowed to enter/exit OFF mode
	* independently.
	* This needs to be set one time thanks to always ON domain.
	*
	* We do not support ES1 behavior anymore. OMAP5 is assumed to be
	* ES2.0, and the same is applicable for DRA7.
	*/
	if (soc_is_omap54xx() \|\| soc_is_dra7xx()) {
	val = __raw_readl(wakeupgen_base + OMAP_AMBA_IF_MODE);
	val \|= BIT(5);
	omap_smc1(OMAP5_MON_AMBA_IF_INDEX, val);
	}

	irq_hotplug_init();
	irq_pm_init();

	return 0;
	}

	/*
	* We cannot use the IRQCHIP_DECLARE macro that lives in
	* drivers/irqchip, so we're forced to roll our own. Not very nice.
	*/
	OF_DECLARE_2(irqchip, ti_wakeupgen, "ti,omap4-wugen-mpu", wakeupgen_init);