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-rw-r--r--arch/x86/kernel/apic/apic_noop.c191
1 files changed, 191 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
new file mode 100644
index 00000000000..775b82bc655
--- /dev/null
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -0,0 +1,191 @@
+/*
+ * NOOP APIC driver.
+ *
+ * Does almost nothing and should be substituted by a real apic driver via
+ * probe routine.
+ *
+ * Though in case if apic is disabled (for some reason) we try
+ * to not uglify the caller's code and allow to call (some) apic routines
+ * like self-ipi, etc...
+ */
+
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <asm/fixmap.h>
+#include <asm/mpspec.h>
+#include <asm/apicdef.h>
+#include <asm/apic.h>
+#include <asm/setup.h>
+
+#include <linux/smp.h>
+#include <asm/ipi.h>
+
+#include <linux/interrupt.h>
+#include <asm/acpi.h>
+#include <asm/e820.h>
+
+static void noop_init_apic_ldr(void) { }
+static void noop_send_IPI_mask(const struct cpumask *cpumask, int vector) { }
+static void noop_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector) { }
+static void noop_send_IPI_allbutself(int vector) { }
+static void noop_send_IPI_all(int vector) { }
+static void noop_send_IPI_self(int vector) { }
+static void noop_apic_wait_icr_idle(void) { }
+static void noop_apic_icr_write(u32 low, u32 id) { }
+
+static int noop_wakeup_secondary_cpu(int apicid, unsigned long start_eip)
+{
+ return -1;
+}
+
+static u32 noop_safe_apic_wait_icr_idle(void)
+{
+ return 0;
+}
+
+static u64 noop_apic_icr_read(void)
+{
+ return 0;
+}
+
+static int noop_phys_pkg_id(int cpuid_apic, int index_msb)
+{
+ return 0;
+}
+
+static unsigned int noop_get_apic_id(unsigned long x)
+{
+ return 0;
+}
+
+static int noop_probe(void)
+{
+ /*
+ * NOOP apic should not ever be
+ * enabled via probe routine
+ */
+ return 0;
+}
+
+static int noop_apic_id_registered(void)
+{
+ /*
+ * if we would be really "pedantic"
+ * we should pass read_apic_id() here
+ * but since NOOP suppose APIC ID = 0
+ * lets save a few cycles
+ */
+ return physid_isset(0, phys_cpu_present_map);
+}
+
+static const struct cpumask *noop_target_cpus(void)
+{
+ /* only BSP here */
+ return cpumask_of(0);
+}
+
+static unsigned long noop_check_apicid_used(physid_mask_t *map, int apicid)
+{
+ return physid_isset(apicid, *map);
+}
+
+static unsigned long noop_check_apicid_present(int bit)
+{
+ return physid_isset(bit, phys_cpu_present_map);
+}
+
+static void noop_vector_allocation_domain(int cpu, struct cpumask *retmask)
+{
+ if (cpu != 0)
+ pr_warning("APIC: Vector allocated for non-BSP cpu\n");
+ cpumask_clear(retmask);
+ cpumask_set_cpu(cpu, retmask);
+}
+
+static u32 noop_apic_read(u32 reg)
+{
+ WARN_ON_ONCE((cpu_has_apic && !disable_apic));
+ return 0;
+}
+
+static void noop_apic_write(u32 reg, u32 v)
+{
+ WARN_ON_ONCE(cpu_has_apic && !disable_apic);
+}
+
+struct apic apic_noop = {
+ .name = "noop",
+ .probe = noop_probe,
+ .acpi_madt_oem_check = NULL,
+
+ .apic_id_registered = noop_apic_id_registered,
+
+ .irq_delivery_mode = dest_LowestPrio,
+ /* logical delivery broadcast to all CPUs: */
+ .irq_dest_mode = 1,
+
+ .target_cpus = noop_target_cpus,
+ .disable_esr = 0,
+ .dest_logical = APIC_DEST_LOGICAL,
+ .check_apicid_used = noop_check_apicid_used,
+ .check_apicid_present = noop_check_apicid_present,
+
+ .vector_allocation_domain = noop_vector_allocation_domain,
+ .init_apic_ldr = noop_init_apic_ldr,
+
+ .ioapic_phys_id_map = default_ioapic_phys_id_map,
+ .setup_apic_routing = NULL,
+ .multi_timer_check = NULL,
+
+ .cpu_present_to_apicid = default_cpu_present_to_apicid,
+ .apicid_to_cpu_present = physid_set_mask_of_physid,
+
+ .setup_portio_remap = NULL,
+ .check_phys_apicid_present = default_check_phys_apicid_present,
+ .enable_apic_mode = NULL,
+
+ .phys_pkg_id = noop_phys_pkg_id,
+
+ .mps_oem_check = NULL,
+
+ .get_apic_id = noop_get_apic_id,
+ .set_apic_id = NULL,
+ .apic_id_mask = 0x0F << 24,
+
+ .cpu_mask_to_apicid = default_cpu_mask_to_apicid,
+ .cpu_mask_to_apicid_and = default_cpu_mask_to_apicid_and,
+
+ .send_IPI_mask = noop_send_IPI_mask,
+ .send_IPI_mask_allbutself = noop_send_IPI_mask_allbutself,
+ .send_IPI_allbutself = noop_send_IPI_allbutself,
+ .send_IPI_all = noop_send_IPI_all,
+ .send_IPI_self = noop_send_IPI_self,
+
+ .wakeup_secondary_cpu = noop_wakeup_secondary_cpu,
+
+ /* should be safe */
+ .trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
+ .trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
+
+ .wait_for_init_deassert = NULL,
+
+ .smp_callin_clear_local_apic = NULL,
+ .inquire_remote_apic = NULL,
+
+ .read = noop_apic_read,
+ .write = noop_apic_write,
+ .icr_read = noop_apic_icr_read,
+ .icr_write = noop_apic_icr_write,
+ .wait_icr_idle = noop_apic_wait_icr_idle,
+ .safe_wait_icr_idle = noop_safe_apic_wait_icr_idle,
+
+#ifdef CONFIG_X86_32
+ .x86_32_early_logical_apicid = noop_x86_32_early_logical_apicid,
+#endif
+};