arch/x86/xen/apic.c

   1 #include <linux/init.h>
   2
   3 #include <asm/x86_init.h>
   4 #include <asm/apic.h>
   5 #include <asm/xen/hypercall.h>
   6
   7 #include <xen/xen.h>
   8 #include <xen/interface/physdev.h>
   9 #include "xen-ops.h"
  10 #include "pmu.h"
  11 #include "smp.h"
  12
  13 static unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
  14 {
  15         struct physdev_apic apic_op;
  16         int ret;
  17
  18         apic_op.apic_physbase = mpc_ioapic_addr(apic);
  19         apic_op.reg = reg;
  20         ret = HYPERVISOR_physdev_op(PHYSDEVOP_apic_read, &apic_op);
  21         if (!ret)
  22                 return apic_op.value;
  23
  24         /* fallback to return an emulated IO_APIC values */
  25         if (reg == 0x1)
  26                 return 0x00170020;
  27         else if (reg == 0x0)
  28                 return apic << 24;
  29
  30         return 0xfd;
  31 }
  32
  33 static unsigned long xen_set_apic_id(unsigned int x)
  34 {
  35         WARN_ON(1);
  36         return x;
  37 }
  38
  39 static unsigned int xen_get_apic_id(unsigned long x)
  40 {
  41         return ((x)>>24) & 0xFFu;
  42 }
  43
  44 static u32 xen_apic_read(u32 reg)
  45 {
  46         struct xen_platform_op op = {
  47                 .cmd = XENPF_get_cpuinfo,
  48                 .interface_version = XENPF_INTERFACE_VERSION,
  49                 .u.pcpu_info.xen_cpuid = 0,
  50         };
  51         int ret = 0;
  52
  53         /* Shouldn't need this as APIC is turned off for PV, and we only
  54          * get called on the bootup processor. But just in case. */
  55         if (!xen_initial_domain() || smp_processor_id())
  56                 return 0;
  57
  58         if (reg == APIC_LVR)
  59                 return 0x10;
  60 #ifdef CONFIG_X86_32
  61         if (reg == APIC_LDR)
  62                 return SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
  63 #endif
  64         if (reg != APIC_ID)
  65                 return 0;
  66
  67         ret = HYPERVISOR_platform_op(&op);
  68         if (ret)
  69                 op.u.pcpu_info.apic_id = BAD_APICID;
  70
  71         return op.u.pcpu_info.apic_id << 24;
  72 }
  73
  74 static void xen_apic_write(u32 reg, u32 val)
  75 {
  76         if (reg == APIC_LVTPC) {
  77                 (void)pmu_apic_update(reg);
  78                 return;
  79         }
  80
  81         /* Warn to see if there's any stray references */
  82         WARN(1,"register: %x, value: %x\n", reg, val);
  83 }
  84
  85 static u64 xen_apic_icr_read(void)
  86 {
  87         return 0;
  88 }
  89
  90 static void xen_apic_icr_write(u32 low, u32 id)
  91 {
  92         /* Warn to see if there's any stray references */
  93         WARN_ON(1);
  94 }
  95
  96 static u32 xen_safe_apic_wait_icr_idle(void)
  97 {
  98         return 0;
  99 }
 100
 101 static int xen_apic_probe_pv(void)
 102 {
 103         if (xen_pv_domain())
 104                 return 1;
 105
 106         return 0;
 107 }
 108
 109 static int xen_madt_oem_check(char *oem_id, char *oem_table_id)
 110 {
 111         return xen_pv_domain();
 112 }
 113
 114 static int xen_id_always_valid(int apicid)
 115 {
 116         return 1;
 117 }
 118
 119 static int xen_id_always_registered(void)
 120 {
 121         return 1;
 122 }
 123
 124 static int xen_phys_pkg_id(int initial_apic_id, int index_msb)
 125 {
 126         return initial_apic_id >> index_msb;
 127 }
 128
 129 #ifdef CONFIG_X86_32
 130 static int xen_x86_32_early_logical_apicid(int cpu)
 131 {
 132         /* Match with APIC_LDR read. Otherwise setup_local_APIC complains. */
 133         return 1 << cpu;
 134 }
 135 #endif
 136
 137 static void xen_noop(void)
 138 {
 139 }
 140
 141 static void xen_silent_inquire(int apicid)
 142 {
 143 }
 144
 145 static int xen_cpu_present_to_apicid(int cpu)
 146 {
 147         if (cpu_present(cpu))
 148                 return xen_get_apic_id(xen_apic_read(APIC_ID));
 149         else
 150                 return BAD_APICID;
 151 }
 152
 153 static struct apic xen_pv_apic = {
 154         .name                           = "Xen PV",
 155         .probe                          = xen_apic_probe_pv,
 156         .acpi_madt_oem_check            = xen_madt_oem_check,
 157         .apic_id_valid                  = xen_id_always_valid,
 158         .apic_id_registered             = xen_id_always_registered,
 159
 160         /* .irq_delivery_mode - used in native_compose_msi_msg only */
 161         /* .irq_dest_mode     - used in native_compose_msi_msg only */
 162
 163         .target_cpus                    = default_target_cpus,
 164         .disable_esr                    = 0,
 165         /* .dest_logical      -  default_send_IPI_ use it but we use our own. */
 166         .check_apicid_used              = default_check_apicid_used, /* Used on 32-bit */
 167
 168         .vector_allocation_domain       = flat_vector_allocation_domain,
 169         .init_apic_ldr                  = xen_noop, /* setup_local_APIC calls it */
 170
 171         .ioapic_phys_id_map             = default_ioapic_phys_id_map, /* Used on 32-bit */
 172         .setup_apic_routing             = NULL,
 173         .cpu_present_to_apicid          = xen_cpu_present_to_apicid,
 174         .apicid_to_cpu_present          = physid_set_mask_of_physid, /* Used on 32-bit */
 175         .check_phys_apicid_present      = default_check_phys_apicid_present, /* smp_sanity_check needs it */
 176         .phys_pkg_id                    = xen_phys_pkg_id, /* detect_ht */
 177
 178         .get_apic_id                    = xen_get_apic_id,
 179         .set_apic_id                    = xen_set_apic_id, /* Can be NULL on 32-bit. */
 180
 181         .cpu_mask_to_apicid_and         = flat_cpu_mask_to_apicid_and,
 182
 183 #ifdef CONFIG_SMP
 184         .send_IPI_mask                  = xen_send_IPI_mask,
 185         .send_IPI_mask_allbutself       = xen_send_IPI_mask_allbutself,
 186         .send_IPI_allbutself            = xen_send_IPI_allbutself,
 187         .send_IPI_all                   = xen_send_IPI_all,
 188         .send_IPI_self                  = xen_send_IPI_self,
 189 #endif
 190         /* .wait_for_init_deassert- used  by AP bootup - smp_callin which we don't use */
 191         .inquire_remote_apic            = xen_silent_inquire,
 192
 193         .read                           = xen_apic_read,
 194         .write                          = xen_apic_write,
 195         .eoi_write                      = xen_apic_write,
 196
 197         .icr_read                       = xen_apic_icr_read,
 198         .icr_write                      = xen_apic_icr_write,
 199         .wait_icr_idle                  = xen_noop,
 200         .safe_wait_icr_idle             = xen_safe_apic_wait_icr_idle,
 201
 202 #ifdef CONFIG_X86_32
 203         /* generic_processor_info and setup_local_APIC. */
 204         .x86_32_early_logical_apicid    = xen_x86_32_early_logical_apicid,
 205 #endif
 206 };
 207
 208 static void __init xen_apic_check(void)
 209 {
 210         if (apic == &xen_pv_apic)
 211                 return;
 212
 213         pr_info("Switched APIC routing from %s to %s.\n", apic->name,
 214                 xen_pv_apic.name);
 215         apic = &xen_pv_apic;
 216 }
 217 void __init xen_init_apic(void)
 218 {
 219         x86_io_apic_ops.read = xen_io_apic_read;
 220         /* On PV guests the APIC CPUID bit is disabled so none of the
 221          * routines end up executing. */
 222         if (!xen_initial_domain())
 223                 apic = &xen_pv_apic;
 224
 225         x86_platform.apic_post_init = xen_apic_check;
 226 }
 227 apic_driver(xen_pv_apic);