[PATCH 1/3] arm64: Add cpuidle context save/restore helpers
From: Marc Zyngier <maz@kernel.org>
Date: 2021-06-08 17:29:21
Subsystem:
arm port, arm64 port (aarch64 architecture), the rest · Maintainers:
Russell King, Catalin Marinas, Will Deacon, Linus Torvalds
As we need to start doing some additional work on all idle paths, let's introduce a set of macros that will perform the work related to the GICv3 pseudo-NMI idle entry exit. Stubs are introduced to 32bit ARM for compatibility. As these helpers are currently unused, the is no functional change. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm/include/asm/cpuidle.h | 5 +++++ arch/arm64/include/asm/cpuidle.h | 35 ++++++++++++++++++++++++++++++++ 2 files changed, 40 insertions(+)
diff --git a/arch/arm/include/asm/cpuidle.h b/arch/arm/include/asm/cpuidle.h
index 0d67ed682e07..1e0b8da12d96 100644
--- a/arch/arm/include/asm/cpuidle.h
+++ b/arch/arm/include/asm/cpuidle.h@@ -49,4 +49,9 @@ extern int arm_cpuidle_suspend(int index); extern int arm_cpuidle_init(int cpu); +struct arm_cpuidle_context { }; + +#define arm_cpuidle_save_context(c) (void)c +#define arm_cpuidle_restore_context(c) (void)c + #endif
diff --git a/arch/arm64/include/asm/cpuidle.h b/arch/arm64/include/asm/cpuidle.h
index 3c5ddb429ea2..53adad0a5c7e 100644
--- a/arch/arm64/include/asm/cpuidle.h
+++ b/arch/arm64/include/asm/cpuidle.h@@ -18,4 +18,39 @@ static inline int arm_cpuidle_suspend(int index) return -EOPNOTSUPP; } #endif + +#ifdef CONFIG_ARM64_PSEUDO_NMI +#include <asm/arch_gicv3.h> + +struct arm_cpuidle_context { + unsigned long pmr; + unsigned long daif_bits; +}; + +#define arm_cpuidle_save_context(__c) \ + do { \ + struct arm_cpuidle_context *c = __c; \ + if (system_uses_irq_prio_masking()) { \ + c->daif_bits = read_sysreg(daif); \ + write_sysreg(c->daif_bits | PSR_I_BIT | PSR_F_BIT, \ + daif); \ + c->pmr = gic_read_pmr(); \ + gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET); \ + } \ + } while (0) + +#define arm_cpuidle_restore_context(__c) \ + do { \ + struct arm_cpuidle_context *c = __c; \ + if (system_uses_irq_prio_masking()) { \ + gic_write_pmr(c->pmr); \ + write_sysreg(c->daif_bits, daif); \ + } \ + } while (0) +#else +struct arm_cpuidle_context { }; + +#define arm_cpuidle_save_context(c) (void)c +#define arm_cpuidle_restore_context(c) (void)c +#endif #endif
--
2.30.2
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