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-rw-r--r--arch/tile/kernel/irq.c280
1 files changed, 0 insertions, 280 deletions
diff --git a/arch/tile/kernel/irq.c b/arch/tile/kernel/irq.c
deleted file mode 100644
index 22044fc691ef..000000000000
--- a/arch/tile/kernel/irq.c
+++ /dev/null
@@ -1,280 +0,0 @@
-/*
- * Copyright 2010 Tilera Corporation. All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation, version 2.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for
- * more details.
- */
-
-#include <linux/module.h>
-#include <linux/seq_file.h>
-#include <linux/interrupt.h>
-#include <linux/irq.h>
-#include <linux/kernel_stat.h>
-#include <linux/uaccess.h>
-#include <hv/drv_pcie_rc_intf.h>
-#include <arch/spr_def.h>
-#include <asm/traps.h>
-#include <linux/perf_event.h>
-
-/* Bit-flag stored in irq_desc->chip_data to indicate HW-cleared irqs. */
-#define IS_HW_CLEARED 1
-
-/*
- * The set of interrupts we enable for arch_local_irq_enable().
- * This is initialized to have just a single interrupt that the kernel
- * doesn't actually use as a sentinel. During kernel init,
- * interrupts are added as the kernel gets prepared to support them.
- * NOTE: we could probably initialize them all statically up front.
- */
-DEFINE_PER_CPU(unsigned long long, interrupts_enabled_mask) =
- INITIAL_INTERRUPTS_ENABLED;
-EXPORT_PER_CPU_SYMBOL(interrupts_enabled_mask);
-
-/* Define per-tile device interrupt statistics state. */
-DEFINE_PER_CPU(irq_cpustat_t, irq_stat) ____cacheline_internodealigned_in_smp;
-EXPORT_PER_CPU_SYMBOL(irq_stat);
-
-/*
- * Define per-tile irq disable mask; the hardware/HV only has a single
- * mask that we use to implement both masking and disabling.
- */
-static DEFINE_PER_CPU(unsigned long, irq_disable_mask)
- ____cacheline_internodealigned_in_smp;
-
-/*
- * Per-tile IRQ nesting depth. Used to make sure we enable newly
- * enabled IRQs before exiting the outermost interrupt.
- */
-static DEFINE_PER_CPU(int, irq_depth);
-
-#if CHIP_HAS_IPI()
-/* Use SPRs to manipulate device interrupts. */
-#define mask_irqs(irq_mask) __insn_mtspr(SPR_IPI_MASK_SET_K, irq_mask)
-#define unmask_irqs(irq_mask) __insn_mtspr(SPR_IPI_MASK_RESET_K, irq_mask)
-#define clear_irqs(irq_mask) __insn_mtspr(SPR_IPI_EVENT_RESET_K, irq_mask)
-#else
-/* Use HV to manipulate device interrupts. */
-#define mask_irqs(irq_mask) hv_disable_intr(irq_mask)
-#define unmask_irqs(irq_mask) hv_enable_intr(irq_mask)
-#define clear_irqs(irq_mask) hv_clear_intr(irq_mask)
-#endif
-
-/*
- * The interrupt handling path, implemented in terms of HV interrupt
- * emulation on TILEPro, and IPI hardware on TILE-Gx.
- * Entered with interrupts disabled.
- */
-void tile_dev_intr(struct pt_regs *regs, int intnum)
-{
- int depth = __this_cpu_inc_return(irq_depth);
- unsigned long original_irqs;
- unsigned long remaining_irqs;
- struct pt_regs *old_regs;
-
-#if CHIP_HAS_IPI()
- /*
- * Pending interrupts are listed in an SPR. We might be
- * nested, so be sure to only handle irqs that weren't already
- * masked by a previous interrupt. Then, mask out the ones
- * we're going to handle.
- */
- unsigned long masked = __insn_mfspr(SPR_IPI_MASK_K);
- original_irqs = __insn_mfspr(SPR_IPI_EVENT_K) & ~masked;
- __insn_mtspr(SPR_IPI_MASK_SET_K, original_irqs);
-#else
- /*
- * Hypervisor performs the equivalent of the Gx code above and
- * then puts the pending interrupt mask into a system save reg
- * for us to find.
- */
- original_irqs = __insn_mfspr(SPR_SYSTEM_SAVE_K_3);
-#endif
- remaining_irqs = original_irqs;
-
- /* Track time spent here in an interrupt context. */
- old_regs = set_irq_regs(regs);
- irq_enter();
-
-#ifdef CONFIG_DEBUG_STACKOVERFLOW
- /* Debugging check for stack overflow: less than 1/8th stack free? */
- {
- long sp = stack_pointer - (long) current_thread_info();
- if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
- pr_emerg("%s: stack overflow: %ld\n",
- __func__, sp - sizeof(struct thread_info));
- dump_stack();
- }
- }
-#endif
- while (remaining_irqs) {
- unsigned long irq = __ffs(remaining_irqs);
- remaining_irqs &= ~(1UL << irq);
-
- /* Count device irqs; Linux IPIs are counted elsewhere. */
- if (irq != IRQ_RESCHEDULE)
- __this_cpu_inc(irq_stat.irq_dev_intr_count);
-
- generic_handle_irq(irq);
- }
-
- /*
- * If we weren't nested, turn on all enabled interrupts,
- * including any that were reenabled during interrupt
- * handling.
- */
- if (depth == 1)
- unmask_irqs(~__this_cpu_read(irq_disable_mask));
-
- __this_cpu_dec(irq_depth);
-
- /*
- * Track time spent against the current process again and
- * process any softirqs if they are waiting.
- */
- irq_exit();
- set_irq_regs(old_regs);
-}
-
-
-/*
- * Remove an irq from the disabled mask. If we're in an interrupt
- * context, defer enabling the HW interrupt until we leave.
- */
-static void tile_irq_chip_enable(struct irq_data *d)
-{
- get_cpu_var(irq_disable_mask) &= ~(1UL << d->irq);
- if (__this_cpu_read(irq_depth) == 0)
- unmask_irqs(1UL << d->irq);
- put_cpu_var(irq_disable_mask);
-}
-
-/*
- * Add an irq to the disabled mask. We disable the HW interrupt
- * immediately so that there's no possibility of it firing. If we're
- * in an interrupt context, the return path is careful to avoid
- * unmasking a newly disabled interrupt.
- */
-static void tile_irq_chip_disable(struct irq_data *d)
-{
- get_cpu_var(irq_disable_mask) |= (1UL << d->irq);
- mask_irqs(1UL << d->irq);
- put_cpu_var(irq_disable_mask);
-}
-
-/* Mask an interrupt. */
-static void tile_irq_chip_mask(struct irq_data *d)
-{
- mask_irqs(1UL << d->irq);
-}
-
-/* Unmask an interrupt. */
-static void tile_irq_chip_unmask(struct irq_data *d)
-{
- unmask_irqs(1UL << d->irq);
-}
-
-/*
- * Clear an interrupt before processing it so that any new assertions
- * will trigger another irq.
- */
-static void tile_irq_chip_ack(struct irq_data *d)
-{
- if ((unsigned long)irq_data_get_irq_chip_data(d) != IS_HW_CLEARED)
- clear_irqs(1UL << d->irq);
-}
-
-/*
- * For per-cpu interrupts, we need to avoid unmasking any interrupts
- * that we disabled via disable_percpu_irq().
- */
-static void tile_irq_chip_eoi(struct irq_data *d)
-{
- if (!(__this_cpu_read(irq_disable_mask) & (1UL << d->irq)))
- unmask_irqs(1UL << d->irq);
-}
-
-static struct irq_chip tile_irq_chip = {
- .name = "tile_irq_chip",
- .irq_enable = tile_irq_chip_enable,
- .irq_disable = tile_irq_chip_disable,
- .irq_ack = tile_irq_chip_ack,
- .irq_eoi = tile_irq_chip_eoi,
- .irq_mask = tile_irq_chip_mask,
- .irq_unmask = tile_irq_chip_unmask,
-};
-
-void __init init_IRQ(void)
-{
- ipi_init();
-}
-
-void setup_irq_regs(void)
-{
- /* Enable interrupt delivery. */
- unmask_irqs(~0UL);
-#if CHIP_HAS_IPI()
- arch_local_irq_unmask(INT_IPI_K);
-#endif
-}
-
-void tile_irq_activate(unsigned int irq, int tile_irq_type)
-{
- /*
- * We use handle_level_irq() by default because the pending
- * interrupt vector (whether modeled by the HV on
- * TILEPro or implemented in hardware on TILE-Gx) has
- * level-style semantics for each bit. An interrupt fires
- * whenever a bit is high, not just at edges.
- */
- irq_flow_handler_t handle = handle_level_irq;
- if (tile_irq_type == TILE_IRQ_PERCPU)
- handle = handle_percpu_irq;
- irq_set_chip_and_handler(irq, &tile_irq_chip, handle);
-
- /*
- * Flag interrupts that are hardware-cleared so that ack()
- * won't clear them.
- */
- if (tile_irq_type == TILE_IRQ_HW_CLEAR)
- irq_set_chip_data(irq, (void *)IS_HW_CLEARED);
-}
-EXPORT_SYMBOL(tile_irq_activate);
-
-
-void ack_bad_irq(unsigned int irq)
-{
- pr_err("unexpected IRQ trap at vector %02x\n", irq);
-}
-
-/*
- * /proc/interrupts printing:
- */
-int arch_show_interrupts(struct seq_file *p, int prec)
-{
-#ifdef CONFIG_PERF_EVENTS
- int i;
-
- seq_printf(p, "%*s: ", prec, "PMI");
-
- for_each_online_cpu(i)
- seq_printf(p, "%10llu ", per_cpu(perf_irqs, i));
- seq_puts(p, " perf_events\n");
-#endif
- return 0;
-}
-
-#if CHIP_HAS_IPI()
-int arch_setup_hwirq(unsigned int irq, int node)
-{
- return irq >= NR_IRQS ? -EINVAL : 0;
-}
-
-void arch_teardown_hwirq(unsigned int irq) { }
-#endif