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Diffstat (limited to 'arch/powerpc/kernel/irq.c')
| -rw-r--r-- | arch/powerpc/kernel/irq.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c new file mode 100644 index 000000000..6f7d4edaa --- /dev/null +++ b/arch/powerpc/kernel/irq.c @@ -0,0 +1,394 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Derived from arch/i386/kernel/irq.c + * Copyright (C) 1992 Linus Torvalds + * Adapted from arch/i386 by Gary Thomas + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * Updated and modified by Cort Dougan <cort@fsmlabs.com> + * Copyright (C) 1996-2001 Cort Dougan + * Adapted for Power Macintosh by Paul Mackerras + * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au) + * + * This file contains the code used by various IRQ handling routines: + * asking for different IRQ's should be done through these routines + * instead of just grabbing them. Thus setups with different IRQ numbers + * shouldn't result in any weird surprises, and installing new handlers + * should be easier. + * + * The MPC8xx has an interrupt mask in the SIU. If a bit is set, the + * interrupt is _enabled_. As expected, IRQ0 is bit 0 in the 32-bit + * mask register (of which only 16 are defined), hence the weird shifting + * and complement of the cached_irq_mask. I want to be able to stuff + * this right into the SIU SMASK register. + * Many of the prep/chrp functions are conditional compiled on CONFIG_PPC_8xx + * to reduce code space and undefined function references. + */ + +#undef DEBUG + +#include <linux/export.h> +#include <linux/threads.h> +#include <linux/kernel_stat.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/ptrace.h> +#include <linux/ioport.h> +#include <linux/interrupt.h> +#include <linux/timex.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/irq.h> +#include <linux/seq_file.h> +#include <linux/cpumask.h> +#include <linux/profile.h> +#include <linux/bitops.h> +#include <linux/list.h> +#include <linux/radix-tree.h> +#include <linux/mutex.h> +#include <linux/pci.h> +#include <linux/debugfs.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/vmalloc.h> +#include <linux/pgtable.h> +#include <linux/static_call.h> + +#include <linux/uaccess.h> +#include <asm/interrupt.h> +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/cache.h> +#include <asm/ptrace.h> +#include <asm/machdep.h> +#include <asm/udbg.h> +#include <asm/smp.h> +#include <asm/hw_irq.h> +#include <asm/softirq_stack.h> +#include <asm/ppc_asm.h> + +#define CREATE_TRACE_POINTS +#include <asm/trace.h> +#include <asm/cpu_has_feature.h> + +DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat); +EXPORT_PER_CPU_SYMBOL(irq_stat); + +#ifdef CONFIG_PPC32 +atomic_t ppc_n_lost_interrupts; + +#ifdef CONFIG_TAU_INT +extern int tau_initialized; +u32 tau_interrupts(unsigned long cpu); +#endif +#endif /* CONFIG_PPC32 */ + +int arch_show_interrupts(struct seq_file *p, int prec) +{ + int j; + +#if defined(CONFIG_PPC32) && defined(CONFIG_TAU_INT) + if (tau_initialized) { + seq_printf(p, "%*s: ", prec, "TAU"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", tau_interrupts(j)); + seq_puts(p, " PowerPC Thermal Assist (cpu temp)\n"); + } +#endif /* CONFIG_PPC32 && CONFIG_TAU_INT */ + + seq_printf(p, "%*s: ", prec, "LOC"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).timer_irqs_event); + seq_printf(p, " Local timer interrupts for timer event device\n"); + + seq_printf(p, "%*s: ", prec, "BCT"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).broadcast_irqs_event); + seq_printf(p, " Broadcast timer interrupts for timer event device\n"); + + seq_printf(p, "%*s: ", prec, "LOC"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).timer_irqs_others); + seq_printf(p, " Local timer interrupts for others\n"); + + seq_printf(p, "%*s: ", prec, "SPU"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).spurious_irqs); + seq_printf(p, " Spurious interrupts\n"); + + seq_printf(p, "%*s: ", prec, "PMI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).pmu_irqs); + seq_printf(p, " Performance monitoring interrupts\n"); + + seq_printf(p, "%*s: ", prec, "MCE"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).mce_exceptions); + seq_printf(p, " Machine check exceptions\n"); + +#ifdef CONFIG_PPC_BOOK3S_64 + if (cpu_has_feature(CPU_FTR_HVMODE)) { + seq_printf(p, "%*s: ", prec, "HMI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", paca_ptrs[j]->hmi_irqs); + seq_printf(p, " Hypervisor Maintenance Interrupts\n"); + } +#endif + + seq_printf(p, "%*s: ", prec, "NMI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).sreset_irqs); + seq_printf(p, " System Reset interrupts\n"); + +#ifdef CONFIG_PPC_WATCHDOG + seq_printf(p, "%*s: ", prec, "WDG"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).soft_nmi_irqs); + seq_printf(p, " Watchdog soft-NMI interrupts\n"); +#endif + +#ifdef CONFIG_PPC_DOORBELL + if (cpu_has_feature(CPU_FTR_DBELL)) { + seq_printf(p, "%*s: ", prec, "DBL"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(irq_stat, j).doorbell_irqs); + seq_printf(p, " Doorbell interrupts\n"); + } +#endif + + return 0; +} + +/* + * /proc/stat helpers + */ +u64 arch_irq_stat_cpu(unsigned int cpu) +{ + u64 sum = per_cpu(irq_stat, cpu).timer_irqs_event; + + sum += per_cpu(irq_stat, cpu).broadcast_irqs_event; + sum += per_cpu(irq_stat, cpu).pmu_irqs; + sum += per_cpu(irq_stat, cpu).mce_exceptions; + sum += per_cpu(irq_stat, cpu).spurious_irqs; + sum += per_cpu(irq_stat, cpu).timer_irqs_others; +#ifdef CONFIG_PPC_BOOK3S_64 + sum += paca_ptrs[cpu]->hmi_irqs; +#endif + sum += per_cpu(irq_stat, cpu).sreset_irqs; +#ifdef CONFIG_PPC_WATCHDOG + sum += per_cpu(irq_stat, cpu).soft_nmi_irqs; +#endif +#ifdef CONFIG_PPC_DOORBELL + sum += per_cpu(irq_stat, cpu).doorbell_irqs; +#endif + + return sum; +} + +static inline void check_stack_overflow(unsigned long sp) +{ + if (!IS_ENABLED(CONFIG_DEBUG_STACKOVERFLOW)) + return; + + sp &= THREAD_SIZE - 1; + + /* check for stack overflow: is there less than 1/4th free? */ + if (unlikely(sp < THREAD_SIZE / 4)) { + pr_err("do_IRQ: stack overflow: %ld\n", sp); + dump_stack(); + } +} + +#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK +static __always_inline void call_do_softirq(const void *sp) +{ + /* Temporarily switch r1 to sp, call __do_softirq() then restore r1. */ + asm volatile ( + PPC_STLU " %%r1, %[offset](%[sp]) ;" + "mr %%r1, %[sp] ;" +#ifdef CONFIG_PPC_KERNEL_PCREL + "bl %[callee]@notoc ;" +#else + "bl %[callee] ;" +#endif + PPC_LL " %%r1, 0(%%r1) ;" + : // Outputs + : // Inputs + [sp] "b" (sp), [offset] "i" (THREAD_SIZE - STACK_FRAME_MIN_SIZE), + [callee] "i" (__do_softirq) + : // Clobbers + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", + "cr7", "r0", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", + "r11", "r12" + ); +} +#endif + +DEFINE_STATIC_CALL_RET0(ppc_get_irq, *ppc_md.get_irq); + +static void __do_irq(struct pt_regs *regs, unsigned long oldsp) +{ + unsigned int irq; + + trace_irq_entry(regs); + + check_stack_overflow(oldsp); + + /* + * Query the platform PIC for the interrupt & ack it. + * + * This will typically lower the interrupt line to the CPU + */ + irq = static_call(ppc_get_irq)(); + + /* We can hard enable interrupts now to allow perf interrupts */ + if (should_hard_irq_enable(regs)) + do_hard_irq_enable(); + + /* And finally process it */ + if (unlikely(!irq)) + __this_cpu_inc(irq_stat.spurious_irqs); + else + generic_handle_irq(irq); + + trace_irq_exit(regs); +} + +static __always_inline void call_do_irq(struct pt_regs *regs, void *sp) +{ + register unsigned long r3 asm("r3") = (unsigned long)regs; + + /* Temporarily switch r1 to sp, call __do_irq() then restore r1. */ + asm volatile ( + PPC_STLU " %%r1, %[offset](%[sp]) ;" + "mr %%r4, %%r1 ;" + "mr %%r1, %[sp] ;" +#ifdef CONFIG_PPC_KERNEL_PCREL + "bl %[callee]@notoc ;" +#else + "bl %[callee] ;" +#endif + PPC_LL " %%r1, 0(%%r1) ;" + : // Outputs + "+r" (r3) + : // Inputs + [sp] "b" (sp), [offset] "i" (THREAD_SIZE - STACK_FRAME_MIN_SIZE), + [callee] "i" (__do_irq) + : // Clobbers + "lr", "xer", "ctr", "memory", "cr0", "cr1", "cr5", "cr6", + "cr7", "r0", "r4", "r5", "r6", "r7", "r8", "r9", "r10", + "r11", "r12" + ); +} + +void __do_IRQ(struct pt_regs *regs) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + void *cursp, *irqsp, *sirqsp; + + /* Switch to the irq stack to handle this */ + cursp = (void *)(current_stack_pointer & ~(THREAD_SIZE - 1)); + irqsp = hardirq_ctx[raw_smp_processor_id()]; + sirqsp = softirq_ctx[raw_smp_processor_id()]; + + /* Already there ? If not switch stack and call */ + if (unlikely(cursp == irqsp || cursp == sirqsp)) + __do_irq(regs, current_stack_pointer); + else + call_do_irq(regs, irqsp); + + set_irq_regs(old_regs); +} + +DEFINE_INTERRUPT_HANDLER_ASYNC(do_IRQ) +{ + __do_IRQ(regs); +} + +static void *__init alloc_vm_stack(void) +{ + return __vmalloc_node(THREAD_SIZE, THREAD_ALIGN, THREADINFO_GFP, + NUMA_NO_NODE, (void *)_RET_IP_); +} + +static void __init vmap_irqstack_init(void) +{ + int i; + + for_each_possible_cpu(i) { + softirq_ctx[i] = alloc_vm_stack(); + hardirq_ctx[i] = alloc_vm_stack(); + } +} + + +void __init init_IRQ(void) +{ + if (IS_ENABLED(CONFIG_VMAP_STACK)) + vmap_irqstack_init(); + + if (ppc_md.init_IRQ) + ppc_md.init_IRQ(); + + if (!WARN_ON(!ppc_md.get_irq)) + static_call_update(ppc_get_irq, ppc_md.get_irq); +} + +#ifdef CONFIG_BOOKE_OR_40x +void *critirq_ctx[NR_CPUS] __read_mostly; +void *dbgirq_ctx[NR_CPUS] __read_mostly; +void *mcheckirq_ctx[NR_CPUS] __read_mostly; +#endif + +void *softirq_ctx[NR_CPUS] __read_mostly; +void *hardirq_ctx[NR_CPUS] __read_mostly; + +#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK +void do_softirq_own_stack(void) +{ + call_do_softirq(softirq_ctx[smp_processor_id()]); +} +#endif + +irq_hw_number_t virq_to_hw(unsigned int virq) +{ + struct irq_data *irq_data = irq_get_irq_data(virq); + return WARN_ON(!irq_data) ? 0 : irq_data->hwirq; +} +EXPORT_SYMBOL_GPL(virq_to_hw); + +#ifdef CONFIG_SMP +int irq_choose_cpu(const struct cpumask *mask) +{ + int cpuid; + + if (cpumask_equal(mask, cpu_online_mask)) { + static int irq_rover; + static DEFINE_RAW_SPINLOCK(irq_rover_lock); + unsigned long flags; + + /* Round-robin distribution... */ +do_round_robin: + raw_spin_lock_irqsave(&irq_rover_lock, flags); + + irq_rover = cpumask_next(irq_rover, cpu_online_mask); + if (irq_rover >= nr_cpu_ids) + irq_rover = cpumask_first(cpu_online_mask); + + cpuid = irq_rover; + + raw_spin_unlock_irqrestore(&irq_rover_lock, flags); + } else { + cpuid = cpumask_first_and(mask, cpu_online_mask); + if (cpuid >= nr_cpu_ids) + goto do_round_robin; + } + + return get_hard_smp_processor_id(cpuid); +} +#else +int irq_choose_cpu(const struct cpumask *mask) +{ + return hard_smp_processor_id(); +} +#endif |