drivers/s390/char/sclp_early.c

   1 /*
   2  * SCLP early driver
   3  *
   4  * Copyright IBM Corp. 2013
   5  */
   6
   7 #define KMSG_COMPONENT "sclp_early"
   8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
   9
  10 #include <asm/ctl_reg.h>
  11 #include <asm/sclp.h>
  12 #include <asm/ipl.h>
  13 #include "sclp_sdias.h"
  14 #include "sclp.h"
  15
  16 #define SCLP_CMDW_READ_SCP_INFO         0x00020001
  17 #define SCLP_CMDW_READ_SCP_INFO_FORCED  0x00120001
  18
  19 struct read_info_sccb {
  20         struct  sccb_header header;     /* 0-7 */
  21         u16     rnmax;                  /* 8-9 */
  22         u8      rnsize;                 /* 10 */
  23         u8      _pad_11[16 - 11];       /* 11-15 */
  24         u16     ncpurl;                 /* 16-17 */
  25         u16     cpuoff;                 /* 18-19 */
  26         u8      _pad_20[24 - 20];       /* 20-23 */
  27         u8      loadparm[8];            /* 24-31 */
  28         u8      _pad_32[42 - 32];       /* 32-41 */
  29         u8      fac42;                  /* 42 */
  30         u8      fac43;                  /* 43 */
  31         u8      _pad_44[48 - 44];       /* 44-47 */
  32         u64     facilities;             /* 48-55 */
  33         u8      _pad_56[66 - 56];       /* 56-65 */
  34         u8      fac66;                  /* 66 */
  35         u8      _pad_67[76 - 67];       /* 67-83 */
  36         u32     ibc;                    /* 76-79 */
  37         u8      _pad80[84 - 80];        /* 80-83 */
  38         u8      fac84;                  /* 84 */
  39         u8      fac85;                  /* 85 */
  40         u8      _pad_86[91 - 86];       /* 86-90 */
  41         u8      flags;                  /* 91 */
  42         u8      _pad_92[100 - 92];      /* 92-99 */
  43         u32     rnsize2;                /* 100-103 */
  44         u64     rnmax2;                 /* 104-111 */
  45         u8      _pad_112[120 - 112];    /* 112-119 */
  46         u16     hcpua;                  /* 120-121 */
  47         u8      _pad_122[4096 - 122];   /* 122-4095 */
  48 } __packed __aligned(PAGE_SIZE);
  49
  50 static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
  51 static unsigned int sclp_con_has_vt220 __initdata;
  52 static unsigned int sclp_con_has_linemode __initdata;
  53 static unsigned long sclp_hsa_size;
  54 static unsigned int sclp_max_cpu;
  55 static struct sclp_ipl_info sclp_ipl_info;
  56 static unsigned char sclp_siif;
  57 static u32 sclp_ibc;
  58 static unsigned int sclp_mtid;
  59 static unsigned int sclp_mtid_cp;
  60 static unsigned int sclp_mtid_max;
  61 static unsigned int sclp_mtid_prev;
  62
  63 u64 sclp_facilities;
  64 u8 sclp_fac84;
  65 unsigned long long sclp_rzm;
  66 unsigned long long sclp_rnmax;
  67
  68 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  69 {
  70         int rc;
  71
  72         __ctl_set_bit(0, 9);
  73         rc = sclp_service_call(cmd, sccb);
  74         if (rc)
  75                 goto out;
  76         __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
  77                         PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
  78         local_irq_disable();
  79 out:
  80         /* Contents of the sccb might have changed. */
  81         barrier();
  82         __ctl_clear_bit(0, 9);
  83         return rc;
  84 }
  85
  86 static int __init sclp_read_info_early(struct read_info_sccb *sccb)
  87 {
  88         int rc, i;
  89         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  90                                   SCLP_CMDW_READ_SCP_INFO};
  91
  92         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  93                 do {
  94                         memset(sccb, 0, sizeof(*sccb));
  95                         sccb->header.length = sizeof(*sccb);
  96                         sccb->header.function_code = 0x80;
  97                         sccb->header.control_mask[2] = 0x80;
  98                         rc = sclp_cmd_sync_early(commands[i], sccb);
  99                 } while (rc == -EBUSY);
 100
 101                 if (rc)
 102                         break;
 103                 if (sccb->header.response_code == 0x10)
 104                         return 0;
 105                 if (sccb->header.response_code != 0x1f0)
 106                         break;
 107         }
 108         return -EIO;
 109 }
 110
 111 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
 112 {
 113         struct sclp_cpu_entry *cpue;
 114         u16 boot_cpu_address, cpu;
 115
 116         if (sclp_read_info_early(sccb))
 117                 return;
 118
 119         sclp_facilities = sccb->facilities;
 120         sclp_fac84 = sccb->fac84;
 121         if (sccb->fac85 & 0x02)
 122                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
 123         sclp_rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 124         sclp_rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 125         sclp_rzm <<= 20;
 126         sclp_ibc = sccb->ibc;
 127
 128         if (!sccb->hcpua) {
 129                 if (MACHINE_IS_VM)
 130                         sclp_max_cpu = 64;
 131                 else
 132                         sclp_max_cpu = sccb->ncpurl;
 133         } else {
 134                 sclp_max_cpu = sccb->hcpua + 1;
 135         }
 136
 137         boot_cpu_address = stap();
 138         cpue = (void *)sccb + sccb->cpuoff;
 139         for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
 140                 if (boot_cpu_address != cpue->core_id)
 141                         continue;
 142                 sclp_siif = cpue->siif;
 143                 break;
 144         }
 145
 146         /* Save IPL information */
 147         sclp_ipl_info.is_valid = 1;
 148         if (sccb->flags & 0x2)
 149                 sclp_ipl_info.has_dump = 1;
 150         memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
 151
 152         sclp_mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
 153         sclp_mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
 154         sclp_mtid_max = max(sclp_mtid, sclp_mtid_cp);
 155         sclp_mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
 156 }
 157
 158 bool __init sclp_has_linemode(void)
 159 {
 160         return !!sclp_con_has_linemode;
 161 }
 162
 163 bool __init sclp_has_vt220(void)
 164 {
 165         return !!sclp_con_has_vt220;
 166 }
 167
 168 unsigned long long sclp_get_rnmax(void)
 169 {
 170         return sclp_rnmax;
 171 }
 172
 173 unsigned long long sclp_get_rzm(void)
 174 {
 175         return sclp_rzm;
 176 }
 177
 178 unsigned int sclp_get_max_cpu(void)
 179 {
 180         return sclp_max_cpu;
 181 }
 182
 183 int sclp_has_siif(void)
 184 {
 185         return sclp_siif;
 186 }
 187 EXPORT_SYMBOL(sclp_has_siif);
 188
 189 unsigned int sclp_get_ibc(void)
 190 {
 191         return sclp_ibc;
 192 }
 193 EXPORT_SYMBOL(sclp_get_ibc);
 194
 195 unsigned int sclp_get_mtid(u8 cpu_type)
 196 {
 197         return cpu_type ? sclp_mtid : sclp_mtid_cp;
 198 }
 199
 200 unsigned int sclp_get_mtid_max(void)
 201 {
 202         return sclp_mtid_max;
 203 }
 204
 205 unsigned int sclp_get_mtid_prev(void)
 206 {
 207         return sclp_mtid_prev;
 208 }
 209
 210 /*
 211  * This function will be called after sclp_facilities_detect(), which gets
 212  * called from early.c code. The sclp_facilities_detect() function retrieves
 213  * and saves the IPL information.
 214  */
 215 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 216 {
 217         *info = sclp_ipl_info;
 218 }
 219
 220 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
 221 {
 222         int rc;
 223
 224         do {
 225                 rc = sclp_cmd_sync_early(cmd, sccb);
 226         } while (rc == -EBUSY);
 227
 228         if (rc)
 229                 return -EIO;
 230         if (((struct sccb_header *) sccb)->response_code != 0x0020)
 231                 return -EIO;
 232         return 0;
 233 }
 234
 235 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
 236 {
 237         memset(sccb, 0, sizeof(*sccb));
 238
 239         sccb->hdr.length = sizeof(*sccb);
 240         sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
 241         sccb->evbuf.hdr.type = EVTYP_SDIAS;
 242         sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
 243         sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
 244         sccb->evbuf.event_id = 4712;
 245         sccb->evbuf.dbs = 1;
 246 }
 247
 248 static int __init sclp_set_event_mask(struct init_sccb *sccb,
 249                                       unsigned long receive_mask,
 250                                       unsigned long send_mask)
 251 {
 252         memset(sccb, 0, sizeof(*sccb));
 253         sccb->header.length = sizeof(*sccb);
 254         sccb->mask_length = sizeof(sccb_mask_t);
 255         sccb->receive_mask = receive_mask;
 256         sccb->send_mask = send_mask;
 257         return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 258 }
 259
 260 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
 261 {
 262         sccb_init_eq_size(sccb);
 263         if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
 264                 return -EIO;
 265         if (sccb->evbuf.blk_cnt == 0)
 266                 return 0;
 267         return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
 268 }
 269
 270 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
 271 {
 272         memset(sccb, 0, PAGE_SIZE);
 273         sccb->length = PAGE_SIZE;
 274         if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
 275                 return -EIO;
 276         if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
 277                 return 0;
 278         return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
 279 }
 280
 281 unsigned long sclp_get_hsa_size(void)
 282 {
 283         return sclp_hsa_size;
 284 }
 285
 286 static void __init sclp_hsa_size_detect(void *sccb)
 287 {
 288         long size;
 289
 290         /* First try synchronous interface (LPAR) */
 291         if (sclp_set_event_mask(sccb, 0, 0x40000010))
 292                 return;
 293         size = sclp_hsa_size_init(sccb);
 294         if (size < 0)
 295                 return;
 296         if (size != 0)
 297                 goto out;
 298         /* Then try asynchronous interface (z/VM) */
 299         if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
 300                 return;
 301         size = sclp_hsa_size_init(sccb);
 302         if (size < 0)
 303                 return;
 304         size = sclp_hsa_copy_wait(sccb);
 305         if (size < 0)
 306                 return;
 307 out:
 308         sclp_hsa_size = size;
 309 }
 310
 311 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
 312 {
 313         if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
 314                 return 0;
 315         if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
 316                 return 0;
 317         return 1;
 318 }
 319
 320 static void __init sclp_console_detect(struct init_sccb *sccb)
 321 {
 322         if (sccb->header.response_code != 0x20)
 323                 return;
 324
 325         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 326                 sclp_con_has_vt220 = 1;
 327
 328         if (sclp_con_check_linemode(sccb))
 329                 sclp_con_has_linemode = 1;
 330 }
 331
 332 void __init sclp_early_detect(void)
 333 {
 334         void *sccb = &sccb_early;
 335
 336         sclp_facilities_detect(sccb);
 337         sclp_hsa_size_detect(sccb);
 338
 339         /* Turn off SCLP event notifications.  Also save remote masks in the
 340          * sccb.  These are sufficient to detect sclp console capabilities.
 341          */
 342         sclp_set_event_mask(sccb, 0, 0);
 343         sclp_console_detect(sccb);
 344 }