1 files changed, 200 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 000000000000..e31b9ffe25f5
--- /dev/null
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -0,0 +1,200 @@
+/*
+ * 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_cpu_to_logical_apicid(int cpu)
+{
+        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);
+}
+
+int noop_apicid_to_node(int logical_apicid)
+{
+        /* we're always on node 0 */
+        return 0;
+}
+
+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,
+        .apicid_to_node                 = noop_apicid_to_node,
+
+        .cpu_to_logical_apicid          = noop_cpu_to_logical_apicid,
+        .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,
+};