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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
*/
#ifndef __ASM_HARDIRQ_H
#define __ASM_HARDIRQ_H
#include <linux/cache.h>
#include <linux/percpu.h>
#include <linux/threads.h>
#include <asm/barrier.h>
#include <asm/irq.h>
#include <asm/kvm_arm.h>
#include <asm/sysreg.h>
#define ack_bad_irq ack_bad_irq
#include <asm-generic/hardirq.h>
#define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
struct nmi_ctx {
u64 hcr;
unsigned int cnt;
};
DECLARE_PER_CPU(struct nmi_ctx, nmi_contexts);
#define arch_nmi_enter() \
do { \
struct nmi_ctx *___ctx; \
u64 ___hcr; \
\
if (!is_kernel_in_hyp_mode()) \
break; \
\
___ctx = this_cpu_ptr(&nmi_contexts); \
if (___ctx->cnt) { \
___ctx->cnt++; \
break; \
} \
\
___hcr = read_sysreg(hcr_el2); \
if (!(___hcr & HCR_TGE)) { \
write_sysreg(___hcr | HCR_TGE, hcr_el2); \
isb(); \
} \
/* \
* Make sure the sysreg write is performed before ___ctx->cnt \
* is set to 1. NMIs that see cnt == 1 will rely on us. \
*/ \
barrier(); \
___ctx->cnt = 1; \
/* \
* Make sure ___ctx->cnt is set before we save ___hcr. We \
* don't want ___ctx->hcr to be overwritten. \
*/ \
barrier(); \
___ctx->hcr = ___hcr; \
} while (0)
#define arch_nmi_exit() \
do { \
struct nmi_ctx *___ctx; \
u64 ___hcr; \
\
if (!is_kernel_in_hyp_mode()) \
break; \
\
___ctx = this_cpu_ptr(&nmi_contexts); \
___hcr = ___ctx->hcr; \
/* \
* Make sure we read ___ctx->hcr before we release \
* ___ctx->cnt as it makes ___ctx->hcr updatable again. \
*/ \
barrier(); \
___ctx->cnt--; \
/* \
* Make sure ___ctx->cnt release is visible before we \
* restore the sysreg. Otherwise a new NMI occurring \
* right after write_sysreg() can be fooled and think \
* we secured things for it. \
*/ \
barrier(); \
if (!___ctx->cnt && !(___hcr & HCR_TGE)) \
write_sysreg(___hcr, hcr_el2); \
} while (0)
static inline void ack_bad_irq(unsigned int irq)
{
extern unsigned long irq_err_count;
irq_err_count++;
}
#endif /* __ASM_HARDIRQ_H */
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