linux_dsm_epyc7002/arch/powerpc/include/asm/hw_irq.h
Christophe Leroy 834e5a6921 powerpc/8xx: use SPRN_EIE and SPRN_EID to enable/disable interrupts
The 8xx has two special registers called EID (External Interrupt
Disable) and EIE (External Interrupt Enable) for clearing/setting
EE in MSR. It avoids the three instructions set mfmsr/ori/mtmsr or
mfmsr/rlwinm/mtmsr and it avoids using a general register.

We just have to write something in the special register to change MSR EE
bit. So we write r0 into the register, regardless of r0 value.

Writing to one of those two special registers also set the MSR RI bit,
but this bit is only unset during beginning of exception prolog and end
of exception epilog. When executing C-functions MSR RI is always set.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-09-25 02:38:53 -05:00

221 lines
4.8 KiB
C

/*
* 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
#endif /* CONFIG_PPC64 */
#ifndef __ASSEMBLY__
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 unsigned long arch_local_save_flags(void)
{
unsigned long flags;
asm volatile(
"lbz %0,%1(13)"
: "=r" (flags)
: "i" (offsetof(struct paca_struct, soft_enabled)));
return flags;
}
static inline unsigned long arch_local_irq_disable(void)
{
unsigned long flags, zero;
asm volatile(
"li %1,0; lbz %0,%2(13); stb %1,%2(13)"
: "=r" (flags), "=&r" (zero)
: "i" (offsetof(struct paca_struct, soft_enabled))
: "memory");
return flags;
}
extern void arch_local_irq_restore(unsigned long);
static inline void arch_local_irq_enable(void)
{
arch_local_irq_restore(1);
}
static inline unsigned long arch_local_irq_save(void)
{
return arch_local_irq_disable();
}
static inline bool arch_irqs_disabled_flags(unsigned long flags)
{
return flags == 0;
}
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 { \
u8 _was_enabled; \
__hard_irq_disable(); \
_was_enabled = local_paca->soft_enabled; \
local_paca->soft_enabled = 0; \
local_paca->irq_happened |= PACA_IRQ_HARD_DIS; \
if (_was_enabled) \
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;
}
extern bool prep_irq_for_idle(void);
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 */