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      _reserved0[16 - 11];    /* 11-15 */
  24         u16     ncpurl;                 /* 16-17 */
  25         u16     cpuoff;                 /* 18-19 */
  26         u8      _reserved7[24 - 20];    /* 20-23 */
  27         u8      loadparm[8];            /* 24-31 */
  28         u8      _reserved1[48 - 32];    /* 32-47 */
  29         u64     facilities;             /* 48-55 */
  30         u8      _reserved2a[76 - 56];   /* 56-75 */
  31         u32     ibc;                    /* 76-79 */
  32         u8      _reserved2b[84 - 80];   /* 80-83 */
  33         u8      fac84;                  /* 84 */
  34         u8      fac85;                  /* 85 */
  35         u8      _reserved3[91 - 86];    /* 86-90 */
  36         u8      flags;                  /* 91 */
  37         u8      _reserved4[100 - 92];   /* 92-99 */
  38         u32     rnsize2;                /* 100-103 */
  39         u64     rnmax2;                 /* 104-111 */
  40         u8      _reserved5[120 - 112];  /* 112-119 */
  41         u16     hcpua;                  /* 120-121 */
  42         u8      _reserved6[4096 - 122]; /* 122-4095 */
  43 } __packed __aligned(PAGE_SIZE);
  44
  45 static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
  46 static unsigned int sclp_con_has_vt220 __initdata;
  47 static unsigned int sclp_con_has_linemode __initdata;
  48 static unsigned long sclp_hsa_size;
  49 static unsigned int sclp_max_cpu;
  50 static struct sclp_ipl_info sclp_ipl_info;
  51 static unsigned char sclp_siif;
  52 static unsigned char sclp_sigpif;
  53 static u32 sclp_ibc;
  54
  55 u64 sclp_facilities;
  56 u8 sclp_fac84;
  57 unsigned long long sclp_rzm;
  58 unsigned long long sclp_rnmax;
  59
  60 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  61 {
  62         int rc;
  63
  64         __ctl_set_bit(0, 9);
  65         rc = sclp_service_call(cmd, sccb);
  66         if (rc)
  67                 goto out;
  68         __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
  69                         PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
  70         local_irq_disable();
  71 out:
  72         /* Contents of the sccb might have changed. */
  73         barrier();
  74         __ctl_clear_bit(0, 9);
  75         return rc;
  76 }
  77
  78 static int __init sclp_read_info_early(struct read_info_sccb *sccb)
  79 {
  80         int rc, i;
  81         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  82                                   SCLP_CMDW_READ_SCP_INFO};
  83
  84         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  85                 do {
  86                         memset(sccb, 0, sizeof(*sccb));
  87                         sccb->header.length = sizeof(*sccb);
  88                         sccb->header.function_code = 0x80;
  89                         sccb->header.control_mask[2] = 0x80;
  90                         rc = sclp_cmd_sync_early(commands[i], sccb);
  91                 } while (rc == -EBUSY);
  92
  93                 if (rc)
  94                         break;
  95                 if (sccb->header.response_code == 0x10)
  96                         return 0;
  97                 if (sccb->header.response_code != 0x1f0)
  98                         break;
  99         }
 100         return -EIO;
 101 }
 102
 103 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
 104 {
 105         struct sclp_cpu_entry *cpue;
 106         u16 boot_cpu_address, cpu;
 107
 108         if (sclp_read_info_early(sccb))
 109                 return;
 110
 111         sclp_facilities = sccb->facilities;
 112         sclp_fac84 = sccb->fac84;
 113         if (sccb->fac85 & 0x02)
 114                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
 115         sclp_rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 116         sclp_rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 117         sclp_rzm <<= 20;
 118         sclp_ibc = sccb->ibc;
 119
 120         if (!sccb->hcpua) {
 121                 if (MACHINE_IS_VM)
 122                         sclp_max_cpu = 64;
 123                 else
 124                         sclp_max_cpu = sccb->ncpurl;
 125         } else {
 126                 sclp_max_cpu = sccb->hcpua + 1;
 127         }
 128
 129         boot_cpu_address = stap();
 130         cpue = (void *)sccb + sccb->cpuoff;
 131         for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
 132                 if (boot_cpu_address != cpue->address)
 133                         continue;
 134                 sclp_siif = cpue->siif;
 135                 sclp_sigpif = cpue->sigpif;
 136                 break;
 137         }
 138
 139         /* Save IPL information */
 140         sclp_ipl_info.is_valid = 1;
 141         if (sccb->flags & 0x2)
 142                 sclp_ipl_info.has_dump = 1;
 143         memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
 144 }
 145
 146 bool __init sclp_has_linemode(void)
 147 {
 148         return !!sclp_con_has_linemode;
 149 }
 150
 151 bool __init sclp_has_vt220(void)
 152 {
 153         return !!sclp_con_has_vt220;
 154 }
 155
 156 unsigned long long sclp_get_rnmax(void)
 157 {
 158         return sclp_rnmax;
 159 }
 160
 161 unsigned long long sclp_get_rzm(void)
 162 {
 163         return sclp_rzm;
 164 }
 165
 166 unsigned int sclp_get_max_cpu(void)
 167 {
 168         return sclp_max_cpu;
 169 }
 170
 171 int sclp_has_siif(void)
 172 {
 173         return sclp_siif;
 174 }
 175 EXPORT_SYMBOL(sclp_has_siif);
 176
 177 int sclp_has_sigpif(void)
 178 {
 179         return sclp_sigpif;
 180 }
 181 EXPORT_SYMBOL(sclp_has_sigpif);
 182
 183 unsigned int sclp_get_ibc(void)
 184 {
 185         return sclp_ibc;
 186 }
 187 EXPORT_SYMBOL(sclp_get_ibc);
 188
 189 /*
 190  * This function will be called after sclp_facilities_detect(), which gets
 191  * called from early.c code. The sclp_facilities_detect() function retrieves
 192  * and saves the IPL information.
 193  */
 194 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 195 {
 196         *info = sclp_ipl_info;
 197 }
 198
 199 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
 200 {
 201         int rc;
 202
 203         do {
 204                 rc = sclp_cmd_sync_early(cmd, sccb);
 205         } while (rc == -EBUSY);
 206
 207         if (rc)
 208                 return -EIO;
 209         if (((struct sccb_header *) sccb)->response_code != 0x0020)
 210                 return -EIO;
 211         return 0;
 212 }
 213
 214 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
 215 {
 216         memset(sccb, 0, sizeof(*sccb));
 217
 218         sccb->hdr.length = sizeof(*sccb);
 219         sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
 220         sccb->evbuf.hdr.type = EVTYP_SDIAS;
 221         sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
 222         sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
 223         sccb->evbuf.event_id = 4712;
 224         sccb->evbuf.dbs = 1;
 225 }
 226
 227 static int __init sclp_set_event_mask(struct init_sccb *sccb,
 228                                       unsigned long receive_mask,
 229                                       unsigned long send_mask)
 230 {
 231         memset(sccb, 0, sizeof(*sccb));
 232         sccb->header.length = sizeof(*sccb);
 233         sccb->mask_length = sizeof(sccb_mask_t);
 234         sccb->receive_mask = receive_mask;
 235         sccb->send_mask = send_mask;
 236         return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 237 }
 238
 239 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
 240 {
 241         sccb_init_eq_size(sccb);
 242         if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
 243                 return -EIO;
 244         if (sccb->evbuf.blk_cnt == 0)
 245                 return 0;
 246         return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
 247 }
 248
 249 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
 250 {
 251         memset(sccb, 0, PAGE_SIZE);
 252         sccb->length = PAGE_SIZE;
 253         if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
 254                 return -EIO;
 255         if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
 256                 return 0;
 257         return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
 258 }
 259
 260 unsigned long sclp_get_hsa_size(void)
 261 {
 262         return sclp_hsa_size;
 263 }
 264
 265 static void __init sclp_hsa_size_detect(void *sccb)
 266 {
 267         long size;
 268
 269         /* First try synchronous interface (LPAR) */
 270         if (sclp_set_event_mask(sccb, 0, 0x40000010))
 271                 return;
 272         size = sclp_hsa_size_init(sccb);
 273         if (size < 0)
 274                 return;
 275         if (size != 0)
 276                 goto out;
 277         /* Then try asynchronous interface (z/VM) */
 278         if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
 279                 return;
 280         size = sclp_hsa_size_init(sccb);
 281         if (size < 0)
 282                 return;
 283         size = sclp_hsa_copy_wait(sccb);
 284         if (size < 0)
 285                 return;
 286 out:
 287         sclp_hsa_size = size;
 288 }
 289
 290 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
 291 {
 292         if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
 293                 return 0;
 294         if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
 295                 return 0;
 296         return 1;
 297 }
 298
 299 static void __init sclp_console_detect(struct init_sccb *sccb)
 300 {
 301         if (sccb->header.response_code != 0x20)
 302                 return;
 303
 304         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 305                 sclp_con_has_vt220 = 1;
 306
 307         if (sclp_con_check_linemode(sccb))
 308                 sclp_con_has_linemode = 1;
 309 }
 310
 311 void __init sclp_early_detect(void)
 312 {
 313         void *sccb = &sccb_early;
 314
 315         sclp_facilities_detect(sccb);
 316         sclp_hsa_size_detect(sccb);
 317
 318         /* Turn off SCLP event notifications.  Also save remote masks in the
 319          * sccb.  These are sufficient to detect sclp console capabilities.
 320          */
 321         sclp_set_event_mask(sccb, 0, 0);
 322         sclp_console_detect(sccb);
 323 }