arch/x86_64/kernel/genapic_flat.c

   1 /*
   2  * Copyright 2004 James Cleverdon, IBM.
   3  * Subject to the GNU Public License, v.2
   4  *
   5  * Flat APIC subarch code.
   6  *
   7  * Hacked for x86-64 by James Cleverdon from i386 architecture code by
   8  * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
   9  * James Cleverdon.
  10  */
  11 #include <linux/config.h>
  12 #include <linux/threads.h>
  13 #include <linux/cpumask.h>
  14 #include <linux/string.h>
  15 #include <linux/kernel.h>
  16 #include <linux/ctype.h>
  17 #include <linux/init.h>
  18 #include <asm/smp.h>
  19 #include <asm/ipi.h>
  20
  21 static cpumask_t flat_target_cpus(void)
  22 {
  23         return cpu_online_map;
  24 }
  25
  26 /*
  27  * Set up the logical destination ID.
  28  *
  29  * Intel recommends to set DFR, LDR and TPR before enabling
  30  * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
  31  * document number 292116).  So here it goes...
  32  */
  33 static void flat_init_apic_ldr(void)
  34 {
  35         unsigned long val;
  36         unsigned long num, id;
  37
  38         num = smp_processor_id();
  39         id = 1UL << num;
  40         x86_cpu_to_log_apicid[num] = id;
  41         apic_write(APIC_DFR, APIC_DFR_FLAT);
  42         val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
  43         val |= SET_APIC_LOGICAL_ID(id);
  44         apic_write(APIC_LDR, val);
  45 }
  46
  47 static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
  48 {
  49         unsigned long mask = cpus_addr(cpumask)[0];
  50         unsigned long cfg;
  51         unsigned long flags;
  52
  53         local_save_flags(flags);
  54         local_irq_disable();
  55
  56         /*
  57          * Wait for idle.
  58          */
  59         apic_wait_icr_idle();
  60
  61         /*
  62          * prepare target chip field
  63          */
  64         cfg = __prepare_ICR2(mask);
  65         apic_write(APIC_ICR2, cfg);
  66
  67         /*
  68          * program the ICR
  69          */
  70         cfg = __prepare_ICR(0, vector, APIC_DEST_LOGICAL);
  71
  72         /*
  73          * Send the IPI. The write to APIC_ICR fires this off.
  74          */
  75         apic_write(APIC_ICR, cfg);
  76         local_irq_restore(flags);
  77 }
  78
  79 static void flat_send_IPI_allbutself(int vector)
  80 {
  81 #ifndef CONFIG_HOTPLUG_CPU
  82         if (((num_online_cpus()) - 1) >= 1)
  83                 __send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL);
  84 #else
  85         cpumask_t allbutme = cpu_online_map;
  86         int me = get_cpu(); /* Ensure we are not preempted when we clear */
  87         cpu_clear(me, allbutme);
  88
  89         if (!cpus_empty(allbutme))
  90                 flat_send_IPI_mask(allbutme, vector);
  91         put_cpu();
  92 #endif
  93 }
  94
  95 static void flat_send_IPI_all(int vector)
  96 {
  97         __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
  98 }
  99
 100 static int flat_apic_id_registered(void)
 101 {
 102         return physid_isset(GET_APIC_ID(apic_read(APIC_ID)), phys_cpu_present_map);
 103 }
 104
 105 static unsigned int flat_cpu_mask_to_apicid(cpumask_t cpumask)
 106 {
 107         return cpus_addr(cpumask)[0] & APIC_ALL_CPUS;
 108 }
 109
 110 static unsigned int phys_pkg_id(int index_msb)
 111 {
 112         u32 ebx;
 113
 114         ebx = cpuid_ebx(1);
 115         return ((ebx >> 24) & 0xFF) >> index_msb;
 116 }
 117
 118 struct genapic apic_flat =  {
 119         .name = "flat",
 120         .int_delivery_mode = dest_LowestPrio,
 121         .int_dest_mode = (APIC_DEST_LOGICAL != 0),
 122         .int_delivery_dest = APIC_DEST_LOGICAL | APIC_DM_LOWEST,
 123         .target_cpus = flat_target_cpus,
 124         .apic_id_registered = flat_apic_id_registered,
 125         .init_apic_ldr = flat_init_apic_ldr,
 126         .send_IPI_all = flat_send_IPI_all,
 127         .send_IPI_allbutself = flat_send_IPI_allbutself,
 128         .send_IPI_mask = flat_send_IPI_mask,
 129         .cpu_mask_to_apicid = flat_cpu_mask_to_apicid,
 130         .phys_pkg_id = phys_pkg_id,
 131 };
 132
 133 /*
 134  * Physflat mode is used when there are more than 8 CPUs on a AMD system.
 135  * We cannot use logical delivery in this case because the mask
 136  * overflows, so use physical mode.
 137  */
 138
 139 static cpumask_t physflat_target_cpus(void)
 140 {
 141         return cpumask_of_cpu(0);
 142 }
 143
 144 static void physflat_send_IPI_mask(cpumask_t cpumask, int vector)
 145 {
 146         send_IPI_mask_sequence(cpumask, vector);
 147 }
 148
 149 static void physflat_send_IPI_allbutself(int vector)
 150 {
 151         cpumask_t allbutme = cpu_online_map;
 152         int me = get_cpu();
 153         cpu_clear(me, allbutme);
 154         physflat_send_IPI_mask(allbutme, vector);
 155         put_cpu();
 156 }
 157
 158 static void physflat_send_IPI_all(int vector)
 159 {
 160         physflat_send_IPI_mask(cpu_online_map, vector);
 161 }
 162
 163 static unsigned int physflat_cpu_mask_to_apicid(cpumask_t cpumask)
 164 {
 165         int cpu;
 166
 167         /*
 168          * We're using fixed IRQ delivery, can only return one phys APIC ID.
 169          * May as well be the first.
 170          */
 171         cpu = first_cpu(cpumask);
 172         if ((unsigned)cpu < NR_CPUS)
 173                 return x86_cpu_to_apicid[cpu];
 174         else
 175                 return BAD_APICID;
 176 }
 177
 178 struct genapic apic_physflat =  {
 179         .name = "physical flat",
 180         .int_delivery_mode = dest_LowestPrio,
 181         .int_dest_mode = (APIC_DEST_PHYSICAL != 0),
 182         .int_delivery_dest = APIC_DEST_PHYSICAL | APIC_DM_LOWEST,
 183         .target_cpus = physflat_target_cpus,
 184         .apic_id_registered = flat_apic_id_registered,
 185         .init_apic_ldr = flat_init_apic_ldr,/*not needed, but shouldn't hurt*/
 186         .send_IPI_all = physflat_send_IPI_all,
 187         .send_IPI_allbutself = physflat_send_IPI_allbutself,
 188         .send_IPI_mask = physflat_send_IPI_mask,
 189         .cpu_mask_to_apicid = physflat_cpu_mask_to_apicid,
 190         .phys_pkg_id = phys_pkg_id,
 191 };