linux_kernel/arch/powerpc/include/asm/hw_irq.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
 */
#ifndef _ASM_POWERPC_HW_IRQ_H
#define _ASM_POWERPC_HW_IRQ_H

#ifdef __KERNEL__

#include <linux/errno.h>
#include <linux/compiler.h>
#include <asm/ptrace.h>
#include <asm/processor.h>

#ifdef CONFIG_PPC64

/*
 * PACA flags in paca->irq_happened.
 *
 * This bits are set when interrupts occur while soft-disabled
 * and allow a proper replay. Additionally, PACA_IRQ_HARD_DIS
 * is set whenever we manually hard disable.
 */
#define PACA_IRQ_HARD_DIS	0x01
#define PACA_IRQ_DBELL		0x02
#define PACA_IRQ_EE		0x04
#define PACA_IRQ_DEC		0x08 /* Or FIT */
#define PACA_IRQ_EE_EDGE	0x10 /* BookE only */
#define PACA_IRQ_HMI		0x20

/*
 * flags for paca->soft_enabled
 */
#define IRQS_ENABLED		0
#define IRQS_DISABLED		1

#endif /* CONFIG_PPC64 */

#ifndef __ASSEMBLY__

extern void replay_system_reset(void);
extern void __replay_interrupt(unsigned int vector);

extern void timer_interrupt(struct pt_regs *);
extern void performance_monitor_exception(struct pt_regs *regs);
extern void WatchdogException(struct pt_regs *regs);
extern void unknown_exception(struct pt_regs *regs);

#ifdef CONFIG_PPC64
#include <asm/paca.h>

static inline notrace unsigned long soft_enabled_return(void)
{
	unsigned long flags;

	asm volatile(
		"lbz %0,%1(13)"
		: "=r" (flags)
		: "i" (offsetof(struct paca_struct, soft_enabled)));

	return flags;
}

/*
 * The "memory" clobber acts as both a compiler barrier
 * for the critical section and as a clobber because
 * we changed paca->soft_enabled
 */
static inline notrace void soft_enabled_set(unsigned long enable)
{
#ifdef CONFIG_TRACE_IRQFLAGS
	/*
	 * mask must always include LINUX bit if any are set, and
	 * interrupts don't get replayed until the Linux interrupt is
	 * unmasked. This could be changed to replay partial unmasks
	 * in future, which would allow Linux masks to nest inside
	 * other masks, among other things. For now, be very dumb and
	 * simple.
	 */
	WARN_ON(mask && !(mask & IRQS_DISABLED));
#endif

	asm volatile(
		"stb %0,%1(13)"
		:
		: "r" (enable),
		  "i" (offsetof(struct paca_struct, soft_enabled))
		: "memory");
}

static inline notrace unsigned long soft_enabled_set_return(unsigned long mask)
{
	unsigned long flags;

#ifdef CONFIG_TRACE_IRQFLAGS
	WARN_ON(mask && !(mask & IRQS_DISABLED));
#endif

	asm volatile(
		"lbz %0,%1(13); stb %2,%1(13)"
		: "=&r" (flags)
		: "i" (offsetof(struct paca_struct, soft_enabled)),
		  "r" (mask)
		: "memory");

	return flags;
}

static inline unsigned long arch_local_save_flags(void)
{
	return soft_enabled_return();
}

static inline void arch_local_irq_disable(void)
{
	soft_enabled_set(IRQS_DISABLED);
}

extern void arch_local_irq_restore(unsigned long);

static inline void arch_local_irq_enable(void)
{
	arch_local_irq_restore(IRQS_ENABLED);
}

static inline unsigned long arch_local_irq_save(void)
{
	return soft_enabled_set_return(IRQS_DISABLED);
}

static inline bool arch_irqs_disabled_flags(unsigned long flags)
{
	return flags & IRQS_DISABLED;
}

static inline bool arch_irqs_disabled(void)
{
	return arch_irqs_disabled_flags(arch_local_save_flags());
}

#ifdef CONFIG_PPC_BOOK3E
#define __hard_irq_enable()	asm volatile("wrteei 1" : : : "memory")
#define __hard_irq_disable()	asm volatile("wrteei 0" : : : "memory")
#else
#define __hard_irq_enable()	__mtmsrd(local_paca->kernel_msr | MSR_EE, 1)
#define __hard_irq_disable()	__mtmsrd(local_paca->kernel_msr, 1)
#endif

#define hard_irq_disable()	do {			\
	unsigned long flags;				\
	__hard_irq_disable();				\
	flags = soft_enabled_set_return(IRQS_DISABLED);\
	local_paca->irq_happened |= PACA_IRQ_HARD_DIS;	\
	if (!arch_irqs_disabled_flags(flags))		\
		trace_hardirqs_off();			\
} while(0)

static inline bool lazy_irq_pending(void)
{
	return !!(get_paca()->irq_happened & ~PACA_IRQ_HARD_DIS);
}

/*
 * This is called by asynchronous interrupts to conditionally
 * re-enable hard interrupts when soft-disabled after having
 * cleared the source of the interrupt
 */
static inline void may_hard_irq_enable(void)
{
	get_paca()->irq_happened &= ~PACA_IRQ_HARD_DIS;
	if (!(get_paca()->irq_happened & PACA_IRQ_EE))
		__hard_irq_enable();
}

static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
{
	return (regs->softe & IRQS_DISABLED);
}

extern bool prep_irq_for_idle(void);
extern bool prep_irq_for_idle_irqsoff(void);
extern void irq_set_pending_from_srr1(unsigned long srr1);

#define fini_irq_for_idle_irqsoff() trace_hardirqs_off();

extern void force_external_irq_replay(void);

#else /* CONFIG_PPC64 */

#define SET_MSR_EE(x)	mtmsr(x)

static inline unsigned long arch_local_save_flags(void)
{
	return mfmsr();
}

static inline void arch_local_irq_restore(unsigned long flags)
{
#if defined(CONFIG_BOOKE)
	asm volatile("wrtee %0" : : "r" (flags) : "memory");
#else
	mtmsr(flags);
#endif
}

static inline unsigned long arch_local_irq_save(void)
{
	unsigned long flags = arch_local_save_flags();
#ifdef CONFIG_BOOKE
	asm volatile("wrteei 0" : : : "memory");
#elif defined(CONFIG_PPC_8xx)
	wrtspr(SPRN_EID);
#else
	SET_MSR_EE(flags & ~MSR_EE);
#endif
	return flags;
}

static inline void arch_local_irq_disable(void)
{
#ifdef CONFIG_BOOKE
	asm volatile("wrteei 0" : : : "memory");
#elif defined(CONFIG_PPC_8xx)
	wrtspr(SPRN_EID);
#else
	arch_local_irq_save();
#endif
}

static inline void arch_local_irq_enable(void)
{
#ifdef CONFIG_BOOKE
	asm volatile("wrteei 1" : : : "memory");
#elif defined(CONFIG_PPC_8xx)
	wrtspr(SPRN_EIE);
#else
	unsigned long msr = mfmsr();
	SET_MSR_EE(msr | MSR_EE);
#endif
}

static inline bool arch_irqs_disabled_flags(unsigned long flags)
{
	return (flags & MSR_EE) == 0;
}

static inline bool arch_irqs_disabled(void)
{
	return arch_irqs_disabled_flags(arch_local_save_flags());
}

#define hard_irq_disable()		arch_local_irq_disable()

static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
{
	return !(regs->msr & MSR_EE);
}

static inline void may_hard_irq_enable(void) { }

#endif /* CONFIG_PPC64 */

#define ARCH_IRQ_INIT_FLAGS	IRQ_NOREQUEST

/*
 * interrupt-retrigger: should we handle this via lost interrupts and IPIs
 * or should we not care like we do now ? --BenH.
 */
struct irq_chip;

#endif  /* __ASSEMBLY__ */
#endif	/* __KERNEL__ */
#endif	/* _ASM_POWERPC_HW_IRQ_H */