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-rw-r--r--arch/tile/kernel/smp.c287
1 files changed, 0 insertions, 287 deletions
diff --git a/arch/tile/kernel/smp.c b/arch/tile/kernel/smp.c
deleted file mode 100644
index 94a62e1197ce..000000000000
--- a/arch/tile/kernel/smp.c
+++ /dev/null
@@ -1,287 +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.
- *
- * TILE SMP support routines.
- */
-
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/irq.h>
-#include <linux/irq_work.h>
-#include <linux/module.h>
-#include <asm/cacheflush.h>
-#include <asm/homecache.h>
-
-/*
- * We write to width and height with a single store in head_NN.S,
- * so make the variable aligned to "long".
- */
-HV_Topology smp_topology __ro_after_init __aligned(sizeof(long));
-EXPORT_SYMBOL(smp_topology);
-
-#if CHIP_HAS_IPI()
-static unsigned long __iomem *ipi_mappings[NR_CPUS];
-#endif
-
-/* Does messaging work correctly to the local cpu? */
-bool self_interrupt_ok;
-
-/*
- * Top-level send_IPI*() functions to send messages to other cpus.
- */
-
-/* Set by smp_send_stop() to avoid recursive panics. */
-static int stopping_cpus;
-
-static void __send_IPI_many(HV_Recipient *recip, int nrecip, int tag)
-{
- int sent = 0;
- while (sent < nrecip) {
- int rc = hv_send_message(recip, nrecip,
- (HV_VirtAddr)&tag, sizeof(tag));
- if (rc < 0) {
- if (!stopping_cpus) /* avoid recursive panic */
- panic("hv_send_message returned %d", rc);
- break;
- }
- WARN_ONCE(rc == 0, "hv_send_message() returned zero\n");
- sent += rc;
- }
-}
-
-void send_IPI_single(int cpu, int tag)
-{
- HV_Recipient recip = {
- .y = cpu / smp_width,
- .x = cpu % smp_width,
- .state = HV_TO_BE_SENT
- };
- __send_IPI_many(&recip, 1, tag);
-}
-
-void send_IPI_many(const struct cpumask *mask, int tag)
-{
- HV_Recipient recip[NR_CPUS];
- int cpu;
- int nrecip = 0;
- int my_cpu = smp_processor_id();
- for_each_cpu(cpu, mask) {
- HV_Recipient *r;
- BUG_ON(cpu == my_cpu);
- r = &recip[nrecip++];
- r->y = cpu / smp_width;
- r->x = cpu % smp_width;
- r->state = HV_TO_BE_SENT;
- }
- __send_IPI_many(recip, nrecip, tag);
-}
-
-void send_IPI_allbutself(int tag)
-{
- struct cpumask mask;
- cpumask_copy(&mask, cpu_online_mask);
- cpumask_clear_cpu(smp_processor_id(), &mask);
- send_IPI_many(&mask, tag);
-}
-
-/*
- * Functions related to starting/stopping cpus.
- */
-
-/* Handler to start the current cpu. */
-static void smp_start_cpu_interrupt(void)
-{
- get_irq_regs()->pc = start_cpu_function_addr;
-}
-
-/* Handler to stop the current cpu. */
-static void smp_stop_cpu_interrupt(void)
-{
- arch_local_irq_disable_all();
- set_cpu_online(smp_processor_id(), 0);
- for (;;)
- asm("nap; nop");
-}
-
-/* This function calls the 'stop' function on all other CPUs in the system. */
-void smp_send_stop(void)
-{
- stopping_cpus = 1;
- send_IPI_allbutself(MSG_TAG_STOP_CPU);
-}
-
-/* On panic, just wait; we may get an smp_send_stop() later on. */
-void panic_smp_self_stop(void)
-{
- while (1)
- asm("nap; nop");
-}
-
-/*
- * Dispatch code called from hv_message_intr() for HV_MSG_TILE hv messages.
- */
-void evaluate_message(int tag)
-{
- switch (tag) {
- case MSG_TAG_START_CPU: /* Start up a cpu */
- smp_start_cpu_interrupt();
- break;
-
- case MSG_TAG_STOP_CPU: /* Sent to shut down slave CPU's */
- smp_stop_cpu_interrupt();
- break;
-
- case MSG_TAG_CALL_FUNCTION_MANY: /* Call function on cpumask */
- generic_smp_call_function_interrupt();
- break;
-
- case MSG_TAG_CALL_FUNCTION_SINGLE: /* Call function on one other CPU */
- generic_smp_call_function_single_interrupt();
- break;
-
- case MSG_TAG_IRQ_WORK: /* Invoke IRQ work */
- irq_work_run();
- break;
-
- default:
- panic("Unknown IPI message tag %d", tag);
- break;
- }
-}
-
-
-/*
- * flush_icache_range() code uses smp_call_function().
- */
-
-struct ipi_flush {
- unsigned long start;
- unsigned long end;
-};
-
-static void ipi_flush_icache_range(void *info)
-{
- struct ipi_flush *flush = (struct ipi_flush *) info;
- __flush_icache_range(flush->start, flush->end);
-}
-
-void flush_icache_range(unsigned long start, unsigned long end)
-{
- struct ipi_flush flush = { start, end };
-
- /* If invoked with irqs disabled, we can not issue IPIs. */
- if (irqs_disabled())
- flush_remote(0, HV_FLUSH_EVICT_L1I, NULL, 0, 0, 0,
- NULL, NULL, 0);
- else {
- preempt_disable();
- on_each_cpu(ipi_flush_icache_range, &flush, 1);
- preempt_enable();
- }
-}
-EXPORT_SYMBOL(flush_icache_range);
-
-
-#ifdef CONFIG_IRQ_WORK
-void arch_irq_work_raise(void)
-{
- if (arch_irq_work_has_interrupt())
- send_IPI_single(smp_processor_id(), MSG_TAG_IRQ_WORK);
-}
-#endif
-
-
-/* Called when smp_send_reschedule() triggers IRQ_RESCHEDULE. */
-static irqreturn_t handle_reschedule_ipi(int irq, void *token)
-{
- __this_cpu_inc(irq_stat.irq_resched_count);
- scheduler_ipi();
-
- return IRQ_HANDLED;
-}
-
-static struct irqaction resched_action = {
- .handler = handle_reschedule_ipi,
- .name = "resched",
- .dev_id = handle_reschedule_ipi /* unique token */,
-};
-
-void __init ipi_init(void)
-{
- int cpu = smp_processor_id();
- HV_Recipient recip = { .y = cpu_y(cpu), .x = cpu_x(cpu),
- .state = HV_TO_BE_SENT };
- int tag = MSG_TAG_CALL_FUNCTION_SINGLE;
-
- /*
- * Test if we can message ourselves for arch_irq_work_raise.
- * This functionality is only available in the Tilera hypervisor
- * in versions 4.3.4 and following.
- */
- if (hv_send_message(&recip, 1, (HV_VirtAddr)&tag, sizeof(tag)) == 1)
- self_interrupt_ok = true;
- else
- pr_warn("Older hypervisor: disabling fast irq_work_raise\n");
-
-#if CHIP_HAS_IPI()
- /* Map IPI trigger MMIO addresses. */
- for_each_possible_cpu(cpu) {
- HV_Coord tile;
- HV_PTE pte;
- unsigned long offset;
-
- tile.x = cpu_x(cpu);
- tile.y = cpu_y(cpu);
- if (hv_get_ipi_pte(tile, KERNEL_PL, &pte) != 0)
- panic("Failed to initialize IPI for cpu %d\n", cpu);
-
- offset = PFN_PHYS(pte_pfn(pte));
- ipi_mappings[cpu] = ioremap_prot(offset, PAGE_SIZE, pte);
- }
-#endif
-
- /* Bind handle_reschedule_ipi() to IRQ_RESCHEDULE. */
- tile_irq_activate(IRQ_RESCHEDULE, TILE_IRQ_PERCPU);
- BUG_ON(setup_irq(IRQ_RESCHEDULE, &resched_action));
-}
-
-#if CHIP_HAS_IPI()
-
-void smp_send_reschedule(int cpu)
-{
- WARN_ON(cpu_is_offline(cpu));
-
- /*
- * We just want to do an MMIO store. The traditional writeq()
- * functions aren't really correct here, since they're always
- * directed at the PCI shim. For now, just do a raw store,
- * casting away the __iomem attribute.
- */
- ((unsigned long __force *)ipi_mappings[cpu])[IRQ_RESCHEDULE] = 0;
-}
-
-#else
-
-void smp_send_reschedule(int cpu)
-{
- HV_Coord coord;
-
- WARN_ON(cpu_is_offline(cpu));
-
- coord.y = cpu_y(cpu);
- coord.x = cpu_x(cpu);
- hv_trigger_ipi(coord, IRQ_RESCHEDULE);
-}
-
-#endif /* CHIP_HAS_IPI() */