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 struct sclp_ipl_info sclp_ipl_info;
  52
  53 struct sclp_info sclp;
  54 EXPORT_SYMBOL(sclp);
  55
  56 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  57 {
  58         int rc;
  59
  60         __ctl_set_bit(0, 9);
  61         rc = sclp_service_call(cmd, sccb);
  62         if (rc)
  63                 goto out;
  64         __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
  65                         PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
  66         local_irq_disable();
  67 out:
  68         /* Contents of the sccb might have changed. */
  69         barrier();
  70         __ctl_clear_bit(0, 9);
  71         return rc;
  72 }
  73
  74 static int __init sclp_read_info_early(struct read_info_sccb *sccb)
  75 {
  76         int rc, i;
  77         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  78                                   SCLP_CMDW_READ_SCP_INFO};
  79
  80         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  81                 do {
  82                         memset(sccb, 0, sizeof(*sccb));
  83                         sccb->header.length = sizeof(*sccb);
  84                         sccb->header.function_code = 0x80;
  85                         sccb->header.control_mask[2] = 0x80;
  86                         rc = sclp_cmd_sync_early(commands[i], sccb);
  87                 } while (rc == -EBUSY);
  88
  89                 if (rc)
  90                         break;
  91                 if (sccb->header.response_code == 0x10)
  92                         return 0;
  93                 if (sccb->header.response_code != 0x1f0)
  94                         break;
  95         }
  96         return -EIO;
  97 }
  98
  99 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
 100 {
 101         struct sclp_core_entry *cpue;
 102         u16 boot_cpu_address, cpu;
 103
 104         if (sclp_read_info_early(sccb))
 105                 return;
 106
 107         sclp.facilities = sccb->facilities;
 108         sclp.has_sprp = !!(sccb->fac84 & 0x02);
 109         sclp.has_core_type = !!(sccb->fac84 & 0x01);
 110         if (sccb->fac85 & 0x02)
 111                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
 112         sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 113         sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 114         sclp.rzm <<= 20;
 115         sclp.ibc = sccb->ibc;
 116
 117         if (!sccb->hcpua) {
 118                 if (MACHINE_IS_VM)
 119                         sclp.max_cores = 64;
 120                 else
 121                         sclp.max_cores = sccb->ncpurl;
 122         } else {
 123                 sclp.max_cores = sccb->hcpua + 1;
 124         }
 125
 126         boot_cpu_address = stap();
 127         cpue = (void *)sccb + sccb->cpuoff;
 128         for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
 129                 if (boot_cpu_address != cpue->core_id)
 130                         continue;
 131                 sclp.has_siif = cpue->siif;
 132                 sclp.has_sigpif = cpue->sigpif;
 133                 break;
 134         }
 135
 136         /* Save IPL information */
 137         sclp_ipl_info.is_valid = 1;
 138         if (sccb->flags & 0x2)
 139                 sclp_ipl_info.has_dump = 1;
 140         memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
 141
 142         sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
 143         sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
 144         sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
 145 }
 146
 147 /*
 148  * This function will be called after sclp_facilities_detect(), which gets
 149  * called from early.c code. The sclp_facilities_detect() function retrieves
 150  * and saves the IPL information.
 151  */
 152 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 153 {
 154         *info = sclp_ipl_info;
 155 }
 156
 157 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
 158 {
 159         int rc;
 160
 161         do {
 162                 rc = sclp_cmd_sync_early(cmd, sccb);
 163         } while (rc == -EBUSY);
 164
 165         if (rc)
 166                 return -EIO;
 167         if (((struct sccb_header *) sccb)->response_code != 0x0020)
 168                 return -EIO;
 169         return 0;
 170 }
 171
 172 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
 173 {
 174         memset(sccb, 0, sizeof(*sccb));
 175
 176         sccb->hdr.length = sizeof(*sccb);
 177         sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
 178         sccb->evbuf.hdr.type = EVTYP_SDIAS;
 179         sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
 180         sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
 181         sccb->evbuf.event_id = 4712;
 182         sccb->evbuf.dbs = 1;
 183 }
 184
 185 static int __init sclp_set_event_mask(struct init_sccb *sccb,
 186                                       unsigned long receive_mask,
 187                                       unsigned long send_mask)
 188 {
 189         memset(sccb, 0, sizeof(*sccb));
 190         sccb->header.length = sizeof(*sccb);
 191         sccb->mask_length = sizeof(sccb_mask_t);
 192         sccb->receive_mask = receive_mask;
 193         sccb->send_mask = send_mask;
 194         return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 195 }
 196
 197 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
 198 {
 199         sccb_init_eq_size(sccb);
 200         if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
 201                 return -EIO;
 202         if (sccb->evbuf.blk_cnt == 0)
 203                 return 0;
 204         return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
 205 }
 206
 207 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
 208 {
 209         memset(sccb, 0, PAGE_SIZE);
 210         sccb->length = PAGE_SIZE;
 211         if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
 212                 return -EIO;
 213         if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
 214                 return 0;
 215         return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
 216 }
 217
 218 static void __init sclp_hsa_size_detect(void *sccb)
 219 {
 220         long size;
 221
 222         /* First try synchronous interface (LPAR) */
 223         if (sclp_set_event_mask(sccb, 0, 0x40000010))
 224                 return;
 225         size = sclp_hsa_size_init(sccb);
 226         if (size < 0)
 227                 return;
 228         if (size != 0)
 229                 goto out;
 230         /* Then try asynchronous interface (z/VM) */
 231         if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
 232                 return;
 233         size = sclp_hsa_size_init(sccb);
 234         if (size < 0)
 235                 return;
 236         size = sclp_hsa_copy_wait(sccb);
 237         if (size < 0)
 238                 return;
 239 out:
 240         sclp.hsa_size = size;
 241 }
 242
 243 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
 244 {
 245         if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
 246                 return 0;
 247         if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
 248                 return 0;
 249         return 1;
 250 }
 251
 252 static void __init sclp_console_detect(struct init_sccb *sccb)
 253 {
 254         if (sccb->header.response_code != 0x20)
 255                 return;
 256
 257         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 258                 sclp.has_vt220 = 1;
 259
 260         if (sclp_con_check_linemode(sccb))
 261                 sclp.has_linemode = 1;
 262 }
 263
 264 void __init sclp_early_detect(void)
 265 {
 266         void *sccb = &sccb_early;
 267
 268         sclp_facilities_detect(sccb);
 269         sclp_hsa_size_detect(sccb);
 270
 271         /* Turn off SCLP event notifications.  Also save remote masks in the
 272          * sccb.  These are sufficient to detect sclp console capabilities.
 273          */
 274         sclp_set_event_mask(sccb, 0, 0);
 275         sclp_console_detect(sccb);
 276 }