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-rw-r--r--arch/x86_64/kernel/genapic_flat.c127
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diff --git a/arch/x86_64/kernel/genapic_flat.c b/arch/x86_64/kernel/genapic_flat.c
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+/*
+ * Copyright 2004 James Cleverdon, IBM.
+ * Subject to the GNU Public License, v.2
+ *
+ * Flat APIC subarch code. Maximum 8 CPUs, logical delivery.
+ *
+ * Hacked for x86-64 by James Cleverdon from i386 architecture code by
+ * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
+ * James Cleverdon.
+ */
+#include <linux/config.h>
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <asm/smp.h>
+#include <asm/ipi.h>
+
+
+static cpumask_t flat_target_cpus(void)
+{
+ return cpu_online_map;
+}
+
+/*
+ * Set up the logical destination ID.
+ *
+ * Intel recommends to set DFR, LDR and TPR before enabling
+ * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
+ * document number 292116). So here it goes...
+ */
+static void flat_init_apic_ldr(void)
+{
+ unsigned long val;
+ unsigned long num, id;
+
+ num = smp_processor_id();
+ id = 1UL << num;
+ x86_cpu_to_log_apicid[num] = id;
+ apic_write_around(APIC_DFR, APIC_DFR_FLAT);
+ val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
+ val |= SET_APIC_LOGICAL_ID(id);
+ apic_write_around(APIC_LDR, val);
+}
+
+static void flat_send_IPI_allbutself(int vector)
+{
+ /*
+ * if there are no other CPUs in the system then
+ * we get an APIC send error if we try to broadcast.
+ * thus we have to avoid sending IPIs in this case.
+ */
+ if (num_online_cpus() > 1)
+ __send_IPI_shortcut(APIC_DEST_ALLBUT, vector, APIC_DEST_LOGICAL);
+}
+
+static void flat_send_IPI_all(int vector)
+{
+ __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
+}
+
+static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
+{
+ unsigned long mask = cpus_addr(cpumask)[0];
+ unsigned long cfg;
+ unsigned long flags;
+
+ local_save_flags(flags);
+ local_irq_disable();
+
+ /*
+ * Wait for idle.
+ */
+ apic_wait_icr_idle();
+
+ /*
+ * prepare target chip field
+ */
+ cfg = __prepare_ICR2(mask);
+ apic_write_around(APIC_ICR2, cfg);
+
+ /*
+ * program the ICR
+ */
+ cfg = __prepare_ICR(0, vector, APIC_DEST_LOGICAL);
+
+ /*
+ * Send the IPI. The write to APIC_ICR fires this off.
+ */
+ apic_write_around(APIC_ICR, cfg);
+ local_irq_restore(flags);
+}
+
+static int flat_apic_id_registered(void)
+{
+ return physid_isset(GET_APIC_ID(apic_read(APIC_ID)), phys_cpu_present_map);
+}
+
+static unsigned int flat_cpu_mask_to_apicid(cpumask_t cpumask)
+{
+ return cpus_addr(cpumask)[0] & APIC_ALL_CPUS;
+}
+
+static unsigned int phys_pkg_id(int index_msb)
+{
+ u32 ebx;
+
+ ebx = cpuid_ebx(1);
+ return ((ebx >> 24) & 0xFF) >> index_msb;
+}
+
+struct genapic apic_flat = {
+ .name = "flat",
+ .int_delivery_mode = dest_LowestPrio,
+ .int_dest_mode = (APIC_DEST_LOGICAL != 0),
+ .int_delivery_dest = APIC_DEST_LOGICAL | APIC_DM_LOWEST,
+ .target_cpus = flat_target_cpus,
+ .apic_id_registered = flat_apic_id_registered,
+ .init_apic_ldr = flat_init_apic_ldr,
+ .send_IPI_all = flat_send_IPI_all,
+ .send_IPI_allbutself = flat_send_IPI_allbutself,
+ .send_IPI_mask = flat_send_IPI_mask,
+ .cpu_mask_to_apicid = flat_cpu_mask_to_apicid,
+ .phys_pkg_id = phys_pkg_id,
+};