kernel/arch/i386/smp.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2008  Tomas 'ZeXx86' Jedrzejek (zexx86@zexos.org)
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 #include <smp.h>
  21 #include <arch/ipi.h>
  22
  23 #define MPC_ENTRY_CPU           0
  24 #define MPC_ENTRY_BUS           1
  25 #define MPC_ENTRY_IOAPIC        2
  26 #define MPC_ENTRY_IOINT         3
  27 #define MPC_ENTRY_LINT          4
  28
  29 #define __PACKED__      __attribute__ ((packed))
  30
  31 struct mp_cpu_entry {
  32         unsigned char type;
  33         unsigned char lapic_id;
  34         unsigned char lapic_ver;
  35         unsigned char cpu_flags;
  36         unsigned cpu_signature;
  37         unsigned cpu_features;
  38 } __PACKED__;
  39
  40 struct mp_cfg_table {
  41         unsigned char signature[4];
  42         unsigned short base_table_len;
  43         unsigned char rev;
  44         unsigned char checksum;
  45         unsigned char oem_id[8];
  46         unsigned char product_id[12];
  47         unsigned oem_table_ptr;
  48         unsigned short oem_table_size;
  49         unsigned short entry_cnt;
  50         unsigned lapic_addr;
  51         unsigned short ext_table_len;
  52         unsigned char ext_table_sum;
  53 } __PACKED__;
  54
  55 struct mp_flt_ptr {
  56         unsigned char signature[4];     /* ASCII signature "_MP_" */
  57         struct mp_cfg_table *mpc_ptr;   /* pointer to the MP configuration structure */
  58         unsigned char len;              /* length of this structure in 16 byte paragraphs */
  59         unsigned char rev;              /* version of the multiprocessing specification */
  60         unsigned char checksum;         /* sum of all bytes in this structure */
  61         unsigned char feature_1;        /* feature flags */
  62         unsigned char feature_2;        /* presence of the ICMR */
  63         unsigned char feature_3;        /* reserved */
  64         unsigned char feature_4;        /* reserved */
  65         unsigned char feature_5;        /* reserved */
  66 } __PACKED__;
  67
  68 struct smp_scan_spots_struct {
  69         unsigned start;
  70         unsigned stop;
  71 };
  72
  73 static struct smp_scan_spots_struct smp_scan_spots[] = {
  74         { 0x9fc00, 0xa0000},
  75         { 0xf0000, 0x100000},
  76         { 0, 0 }
  77 };
  78
  79
  80 static unsigned *arch_smp_probe (unsigned base, unsigned limit)
  81 {
  82         char *ptr;
  83
  84         for (ptr = (char *) base; (unsigned) ptr < limit; ptr ++) {
  85                 if (*ptr == '_') {
  86                         if (!strncmp (ptr, "_MP_", 4))
  87                                 return (unsigned *) ptr;
  88                 }
  89         }
  90         return 0;
  91 }
  92
  93 static struct mp_flt_ptr *arch_smp_find_mp_config ()
  94 {
  95         int i;
  96         struct mp_flt_ptr *mp_flt = 0;
  97
  98         for (i = 0; smp_scan_spots[i].stop; i ++) {
  99                 mp_flt = (struct mp_flt_ptr *) arch_smp_probe (smp_scan_spots[i].start, smp_scan_spots[i].stop);
 100
 101                 if (mp_flt)
 102                         break;
 103         }
 104
 105         return mp_flt;
 106 }
 107
 108 static char *arch_smp_mpc_entry (char *entry)
 109 {
 110         unsigned type = (unsigned) *entry;
 111         struct mp_cpu_entry *cpu;
 112
 113         switch (type) {
 114                 case MPC_ENTRY_CPU:
 115                         cpu = (struct mp_cpu_entry *) entry;
 116                         entry += 20;
 117
 118                         if (!(cpu->cpu_flags & 1))
 119                                 break;
 120
 121                         smp_arch_x86 *arch_spec = (smp_arch_x86 *) kmalloc (sizeof (smp_arch_x86));
 122
 123                         if (!arch_spec)
 124                                 return 0;
 125
 126                         arch_spec->lapic_id = cpu->lapic_id;
 127                         arch_spec->lapic_ver = cpu->lapic_ver;
 128                         arch_spec->cpuid = cpu->cpu_signature;
 129                         arch_spec->features = cpu->cpu_features;
 130
 131                         if (!smp_cpu_register (SMP_ARCH_x86, (cpu->cpu_flags & 2) ? SMP_STATE_CPU_UP : SMP_STATE_CPU_DOWN,
 132                             (cpu->cpu_flags & 2) ? SMP_FLAGS_CPU_BS : SMP_FLAGS_CPU_AP, arch_spec))
 133                                 return 0;
 134
 135                         break;
 136                 default:
 137                         entry += 8;
 138                         break;
 139         }
 140
 141         return entry;
 142 }
 143
 144 static void arch_smp_sleep (int t)
 145 {
 146         int_enable ();
 147         timer_wait (t);
 148         int_enable ();
 149 }
 150
 151 static unsigned arch_smp_cpuboot (unsigned lapic_id)
 152 {
 153         arch_ipi_send (lapic_id, IPI_TYPE_INIT, 0);
 154
 155         arch_smp_sleep (100);
 156
 157         arch_ipi_send (lapic_id, IPI_TYPE_SIPI, SMP_ARCH_x86_TRAMPOLINE / 0x1000);
 158
 159         /*arch_smp_sleep (200);
 160         arch_ipi_send (lapic_id, IPI_TYPE_SIPI, 0x07);
 161         arch_smp_sleep (200);*/
 162
 163         return 1;
 164 }
 165
 166 extern void gdt_smp ();
 167
 168 unsigned arch_smp_trampoline ()
 169 {
 170 /*      asm volatile (
 171                 "mov %cs, %ax;"
 172                 "mov %ax, %ds;"
 173         );*/
 174
 175         /* enable protected mode on AP cpu */
 176         /*asm volatile (
 177                 "movl %cr0, %eax;"
 178                 "orl $(1<<0), %eax;"
 179                 "movl %eax, %cr0;"
 180         );*/
 181
 182 /*asm volatile (
 183         "mov $0x4F02, %ax;"
 184         "int $0x10;"
 185         "sti;"
 186 );*/
 187
 188         /* hang up processor - TODO */
 189         while (1)
 190                 asm ("hlt");
 191
 192         return 1;
 193 }
 194
 195 unsigned arch_smp_init ()
 196 {
 197         struct mp_cfg_table *mpc_ptr = 0;
 198         struct mp_flt_ptr *mp_flt = arch_smp_find_mp_config ();
 199
 200         /* this pc is not smp capable */
 201         if (!mp_flt)
 202                 return 0;
 203
 204         /* check for intel spec. */
 205         if (mp_flt->feature_1) {
 206                 /* TODO */
 207                 return 0;
 208         } else
 209                 mpc_ptr = mp_flt->mpc_ptr;
 210
 211         if (!mpc_ptr)
 212                 return 0;
 213
 214         /* verify MP Configuration Table signature */
 215         if (strncmp (mpc_ptr->signature, "PCMP", 4))
 216                 return 0;
 217
 218         /* save lapic address */
 219         ipi_lapic_init (mpc_ptr->lapic_addr);
 220
 221         unsigned i;
 222         char *entry_ptr = (char *) mpc_ptr + 44;
 223
 224         for (i = 0; i < mpc_ptr->entry_cnt; i ++)
 225                 entry_ptr = arch_smp_mpc_entry (entry_ptr);
 226
 227         memcpy (SMP_ARCH_x86_TRAMPOLINE, &arch_smp_trampoline, sizeof (&arch_smp_trampoline));
 228
 229         smp_cpu_t *cpu = 0;
 230
 231         while (cpu = smp_cpu_getnextcpu (cpu)) {
 232                 /* check for AP processor */
 233                 if (cpu->flags != SMP_FLAGS_CPU_AP)
 234                         continue;
 235
 236                 smp_arch_x86 *arch_spec = cpu->arch_spec;
 237
 238                 if (!arch_spec)
 239                         continue;
 240
 241                 /* try to boot AP processor */
 242                 if (arch_smp_cpuboot (arch_spec->lapic_id))
 243                         cpu->state = SMP_STATE_CPU_UP;
 244         }
 245
 246         return 1;
 247 }