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Diffstat (limited to 'arch/ia64/kernel/irq.c')
| -rw-r--r-- | arch/ia64/kernel/irq.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c new file mode 100644 index 000000000..ecef17c7c --- /dev/null +++ b/arch/ia64/kernel/irq.c @@ -0,0 +1,181 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/arch/ia64/kernel/irq.c + * + * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar + * + * This file contains the code used by various IRQ handling routines: + * asking for different IRQs 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. + * + * Copyright (C) Ashok Raj<ashok.raj@intel.com>, Intel Corporation 2004 + * + * 4/14/2004: Added code to handle cpu migration and do safe irq + * migration without losing interrupts for iosapic + * architecture. + */ + +#include <asm/delay.h> +#include <linux/uaccess.h> +#include <linux/module.h> +#include <linux/seq_file.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> + +#include <asm/mca.h> +#include <asm/xtp.h> + +/* + * 'what should we do if we get a hw irq event on an illegal vector'. + * each architecture has to answer this themselves. + */ +void ack_bad_irq(unsigned int irq) +{ + printk(KERN_ERR "Unexpected irq vector 0x%x on CPU %u!\n", irq, smp_processor_id()); +} + +/* + * Interrupt statistics: + */ + +atomic_t irq_err_count; + +/* + * /proc/interrupts printing: + */ +int arch_show_interrupts(struct seq_file *p, int prec) +{ + seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); + return 0; +} + +#ifdef CONFIG_SMP +static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 }; + +void set_irq_affinity_info (unsigned int irq, int hwid, int redir) +{ + if (irq < NR_IRQS) { + cpumask_copy(irq_get_affinity_mask(irq), + cpumask_of(cpu_logical_id(hwid))); + irq_redir[irq] = (char) (redir & 0xff); + } +} +#endif /* CONFIG_SMP */ + +int __init arch_early_irq_init(void) +{ + ia64_mca_irq_init(); + return 0; +} + +#ifdef CONFIG_HOTPLUG_CPU +unsigned int vectors_in_migration[NR_IRQS]; + +/* + * Since cpu_online_mask is already updated, we just need to check for + * affinity that has zeros + */ +static void migrate_irqs(void) +{ + int irq, new_cpu; + + for (irq=0; irq < NR_IRQS; irq++) { + struct irq_desc *desc = irq_to_desc(irq); + struct irq_data *data = irq_desc_get_irq_data(desc); + struct irq_chip *chip = irq_data_get_irq_chip(data); + + if (irqd_irq_disabled(data)) + continue; + + /* + * No handling for now. + * TBD: Implement a disable function so we can now + * tell CPU not to respond to these local intr sources. + * such as ITV,CPEI,MCA etc. + */ + if (irqd_is_per_cpu(data)) + continue; + + if (cpumask_any_and(irq_data_get_affinity_mask(data), + cpu_online_mask) >= nr_cpu_ids) { + /* + * Save it for phase 2 processing + */ + vectors_in_migration[irq] = irq; + + new_cpu = cpumask_any(cpu_online_mask); + + /* + * Al three are essential, currently WARN_ON.. maybe panic? + */ + if (chip && chip->irq_disable && + chip->irq_enable && chip->irq_set_affinity) { + chip->irq_disable(data); + chip->irq_set_affinity(data, + cpumask_of(new_cpu), false); + chip->irq_enable(data); + } else { + WARN_ON((!chip || !chip->irq_disable || + !chip->irq_enable || + !chip->irq_set_affinity)); + } + } + } +} + +void fixup_irqs(void) +{ + unsigned int irq; + extern void ia64_process_pending_intr(void); + extern volatile int time_keeper_id; + + /* Mask ITV to disable timer */ + ia64_set_itv(1 << 16); + + /* + * Find a new timesync master + */ + if (smp_processor_id() == time_keeper_id) { + time_keeper_id = cpumask_first(cpu_online_mask); + printk ("CPU %d is now promoted to time-keeper master\n", time_keeper_id); + } + + /* + * Phase 1: Locate IRQs bound to this cpu and + * relocate them for cpu removal. + */ + migrate_irqs(); + + /* + * Phase 2: Perform interrupt processing for all entries reported in + * local APIC. + */ + ia64_process_pending_intr(); + + /* + * Phase 3: Now handle any interrupts not captured in local APIC. + * This is to account for cases that device interrupted during the time the + * rte was being disabled and re-programmed. + */ + for (irq=0; irq < NR_IRQS; irq++) { + if (vectors_in_migration[irq]) { + struct pt_regs *old_regs = set_irq_regs(NULL); + + vectors_in_migration[irq]=0; + generic_handle_irq(irq); + set_irq_regs(old_regs); + } + } + + /* + * Now let processor die. We do irq disable and max_xtp() to + * ensure there is no more interrupts routed to this processor. + * But the local timer interrupt can have 1 pending which we + * take care in timer_interrupt(). + */ + max_xtp(); + local_irq_disable(); +} +#endif |