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 <linux/errno.h>
  11 #include <asm/ctl_reg.h>
  12 #include <asm/sclp.h>
  13 #include <asm/ipl.h>
  14 #include "sclp_sdias.h"
  15 #include "sclp.h"
  16
  17 #define SCLP_CMDW_READ_SCP_INFO         0x00020001
  18 #define SCLP_CMDW_READ_SCP_INFO_FORCED  0x00120001
  19
  20 struct read_info_sccb {
  21         struct  sccb_header header;     /* 0-7 */
  22         u16     rnmax;                  /* 8-9 */
  23         u8      rnsize;                 /* 10 */
  24         u8      _pad_11[16 - 11];       /* 11-15 */
  25         u16     ncpurl;                 /* 16-17 */
  26         u16     cpuoff;                 /* 18-19 */
  27         u8      _pad_20[24 - 20];       /* 20-23 */
  28         u8      loadparm[8];            /* 24-31 */
  29         u8      _pad_32[42 - 32];       /* 32-41 */
  30         u8      fac42;                  /* 42 */
  31         u8      fac43;                  /* 43 */
  32         u8      _pad_44[48 - 44];       /* 44-47 */
  33         u64     facilities;             /* 48-55 */
  34         u8      _pad_56[66 - 56];       /* 56-65 */
  35         u8      fac66;                  /* 66 */
  36         u8      _pad_67[76 - 67];       /* 67-83 */
  37         u32     ibc;                    /* 76-79 */
  38         u8      _pad80[84 - 80];        /* 80-83 */
  39         u8      fac84;                  /* 84 */
  40         u8      fac85;                  /* 85 */
  41         u8      _pad_86[91 - 86];       /* 86-90 */
  42         u8      flags;                  /* 91 */
  43         u8      _pad_92[99 - 92];       /* 92-98 */
  44         u8      hamaxpow;               /* 99 */
  45         u32     rnsize2;                /* 100-103 */
  46         u64     rnmax2;                 /* 104-111 */
  47         u8      _pad_112[116 - 112];    /* 112-115 */
  48         u8      fac116;                 /* 116 */
  49         u8      _pad_117[119 - 117];    /* 117-118 */
  50         u8      fac119;                 /* 119 */
  51         u16     hcpua;                  /* 120-121 */
  52         u8      _pad_122[124 - 122];    /* 122-123 */
  53         u32     hmfai;                  /* 124-127 */
  54         u8      _pad_128[4096 - 128];   /* 128-4095 */
  55 } __packed __aligned(PAGE_SIZE);
  56
  57 static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
  58 static struct sclp_ipl_info sclp_ipl_info;
  59
  60 struct sclp_info sclp;
  61 EXPORT_SYMBOL(sclp);
  62
  63 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  64 {
  65         int rc;
  66
  67         __ctl_set_bit(0, 9);
  68         rc = sclp_service_call(cmd, sccb);
  69         if (rc)
  70                 goto out;
  71         __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
  72                         PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
  73         local_irq_disable();
  74 out:
  75         /* Contents of the sccb might have changed. */
  76         barrier();
  77         __ctl_clear_bit(0, 9);
  78         return rc;
  79 }
  80
  81 static int __init sclp_read_info_early(struct read_info_sccb *sccb)
  82 {
  83         int rc, i;
  84         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  85                                   SCLP_CMDW_READ_SCP_INFO};
  86
  87         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  88                 do {
  89                         memset(sccb, 0, sizeof(*sccb));
  90                         sccb->header.length = sizeof(*sccb);
  91                         sccb->header.function_code = 0x80;
  92                         sccb->header.control_mask[2] = 0x80;
  93                         rc = sclp_cmd_sync_early(commands[i], sccb);
  94                 } while (rc == -EBUSY);
  95
  96                 if (rc)
  97                         break;
  98                 if (sccb->header.response_code == 0x10)
  99                         return 0;
 100                 if (sccb->header.response_code != 0x1f0)
 101                         break;
 102         }
 103         return -EIO;
 104 }
 105
 106 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
 107 {
 108         struct sclp_core_entry *cpue;
 109         u16 boot_cpu_address, cpu;
 110
 111         if (sclp_read_info_early(sccb))
 112                 return;
 113
 114         sclp.facilities = sccb->facilities;
 115         sclp.has_sprp = !!(sccb->fac84 & 0x02);
 116         sclp.has_core_type = !!(sccb->fac84 & 0x01);
 117         sclp.has_esca = !!(sccb->fac116 & 0x08);
 118         sclp.has_hvs = !!(sccb->fac119 & 0x80);
 119         if (sccb->fac85 & 0x02)
 120                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
 121         sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 122         sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 123         sclp.rzm <<= 20;
 124         sclp.ibc = sccb->ibc;
 125
 126         if (sccb->hamaxpow && sccb->hamaxpow < 64)
 127                 sclp.hamax = (1UL << sccb->hamaxpow) - 1;
 128         else
 129                 sclp.hamax = U64_MAX;
 130
 131         if (!sccb->hcpua) {
 132                 if (MACHINE_IS_VM)
 133                         sclp.max_cores = 64;
 134                 else
 135                         sclp.max_cores = sccb->ncpurl;
 136         } else {
 137                 sclp.max_cores = sccb->hcpua + 1;
 138         }
 139
 140         boot_cpu_address = stap();
 141         cpue = (void *)sccb + sccb->cpuoff;
 142         for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
 143                 if (boot_cpu_address != cpue->core_id)
 144                         continue;
 145                 sclp.has_siif = cpue->siif;
 146                 sclp.has_sigpif = cpue->sigpif;
 147                 sclp.has_sief2 = cpue->sief2;
 148                 break;
 149         }
 150
 151         /* Save IPL information */
 152         sclp_ipl_info.is_valid = 1;
 153         if (sccb->flags & 0x2)
 154                 sclp_ipl_info.has_dump = 1;
 155         memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
 156
 157         sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
 158         sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
 159         sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
 160
 161         sclp.hmfai = sccb->hmfai;
 162 }
 163
 164 /*
 165  * This function will be called after sclp_facilities_detect(), which gets
 166  * called from early.c code. The sclp_facilities_detect() function retrieves
 167  * and saves the IPL information.
 168  */
 169 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 170 {
 171         *info = sclp_ipl_info;
 172 }
 173
 174 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
 175 {
 176         int rc;
 177
 178         do {
 179                 rc = sclp_cmd_sync_early(cmd, sccb);
 180         } while (rc == -EBUSY);
 181
 182         if (rc)
 183                 return -EIO;
 184         if (((struct sccb_header *) sccb)->response_code != 0x0020)
 185                 return -EIO;
 186         return 0;
 187 }
 188
 189 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
 190 {
 191         memset(sccb, 0, sizeof(*sccb));
 192
 193         sccb->hdr.length = sizeof(*sccb);
 194         sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
 195         sccb->evbuf.hdr.type = EVTYP_SDIAS;
 196         sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
 197         sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
 198         sccb->evbuf.event_id = 4712;
 199         sccb->evbuf.dbs = 1;
 200 }
 201
 202 static int __init sclp_set_event_mask(struct init_sccb *sccb,
 203                                       unsigned long receive_mask,
 204                                       unsigned long send_mask)
 205 {
 206         memset(sccb, 0, sizeof(*sccb));
 207         sccb->header.length = sizeof(*sccb);
 208         sccb->mask_length = sizeof(sccb_mask_t);
 209         sccb->receive_mask = receive_mask;
 210         sccb->send_mask = send_mask;
 211         return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 212 }
 213
 214 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
 215 {
 216         sccb_init_eq_size(sccb);
 217         if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
 218                 return -EIO;
 219         if (sccb->evbuf.blk_cnt == 0)
 220                 return 0;
 221         return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
 222 }
 223
 224 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
 225 {
 226         memset(sccb, 0, PAGE_SIZE);
 227         sccb->length = PAGE_SIZE;
 228         if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
 229                 return -EIO;
 230         if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
 231                 return 0;
 232         return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
 233 }
 234
 235 static void __init sclp_hsa_size_detect(void *sccb)
 236 {
 237         long size;
 238
 239         /* First try synchronous interface (LPAR) */
 240         if (sclp_set_event_mask(sccb, 0, 0x40000010))
 241                 return;
 242         size = sclp_hsa_size_init(sccb);
 243         if (size < 0)
 244                 return;
 245         if (size != 0)
 246                 goto out;
 247         /* Then try asynchronous interface (z/VM) */
 248         if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
 249                 return;
 250         size = sclp_hsa_size_init(sccb);
 251         if (size < 0)
 252                 return;
 253         size = sclp_hsa_copy_wait(sccb);
 254         if (size < 0)
 255                 return;
 256 out:
 257         sclp.hsa_size = size;
 258 }
 259
 260 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
 261 {
 262         if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
 263                 return 0;
 264         if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
 265                 return 0;
 266         return 1;
 267 }
 268
 269 static void __init sclp_console_detect(struct init_sccb *sccb)
 270 {
 271         if (sccb->header.response_code != 0x20)
 272                 return;
 273
 274         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 275                 sclp.has_vt220 = 1;
 276
 277         if (sclp_con_check_linemode(sccb))
 278                 sclp.has_linemode = 1;
 279 }
 280
 281 void __init sclp_early_detect(void)
 282 {
 283         void *sccb = &sccb_early;
 284
 285         sclp_facilities_detect(sccb);
 286         sclp_hsa_size_detect(sccb);
 287
 288         /* Turn off SCLP event notifications.  Also save remote masks in the
 289          * sccb.  These are sufficient to detect sclp console capabilities.
 290          */
 291         sclp_set_event_mask(sccb, 0, 0);
 292         sclp_console_detect(sccb);
 293 }