From e79321883842ca7b77d8a58fe8303e8da35c085e Mon Sep 17 00:00:00 2001 From: Julien Thierry Date: Thu, 31 Jan 2019 14:58:55 +0000 Subject: arm64: Switch to PMR masking when starting CPUs Once the boot CPU has been prepared or a new secondary CPU has been brought up, use ICC_PMR_EL1 to mask interrupts on that CPU and clear PSR.I bit. Since ICC_PMR_EL1 is initialized at CPU bringup, avoid overwriting it in the GICv3 driver. Signed-off-by: Julien Thierry Suggested-by: Daniel Thompson Acked-by: Marc Zyngier Cc: Will Deacon Cc: James Morse Cc: Marc Zyngier Signed-off-by: Catalin Marinas --- arch/arm64/kernel/smp.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'arch') diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index a944edd39d2d..824de7038967 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include #include @@ -180,6 +181,24 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) return ret; } +static void init_gic_priority_masking(void) +{ + u32 cpuflags; + + if (WARN_ON(!gic_enable_sre())) + return; + + cpuflags = read_sysreg(daif); + + WARN_ON(!(cpuflags & PSR_I_BIT)); + + gic_write_pmr(GIC_PRIO_IRQOFF); + + /* We can only unmask PSR.I if we can take aborts */ + if (!(cpuflags & PSR_A_BIT)) + write_sysreg(cpuflags & ~PSR_I_BIT, daif); +} + /* * This is the secondary CPU boot entry. We're using this CPUs * idle thread stack, but a set of temporary page tables. @@ -206,6 +225,9 @@ asmlinkage notrace void secondary_start_kernel(void) */ cpu_uninstall_idmap(); + if (system_uses_irq_prio_masking()) + init_gic_priority_masking(); + preempt_disable(); trace_hardirqs_off(); @@ -426,6 +448,10 @@ void __init smp_prepare_boot_cpu(void) * and/or scheduling is enabled. */ apply_boot_alternatives(); + + /* Conditionally switch to GIC PMR for interrupt masking */ + if (system_uses_irq_prio_masking()) + init_gic_priority_masking(); } static u64 __init of_get_cpu_mpidr(struct device_node *dn) -- cgit v1.2.3