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[100 - 92];      /* 92-99 */
  44         u32     rnsize2;                /* 100-103 */
  45         u64     rnmax2;                 /* 104-111 */
  46         u8      _pad_112[116 - 112];    /* 112-115 */
  47         u8      fac116;                 /* 116 */
  48         u8      _pad_117[119 - 117];    /* 117-118 */
  49         u8      fac119;                 /* 119 */
  50         u16     hcpua;                  /* 120-121 */
  51         u8      _pad_122[4096 - 122];   /* 122-4095 */
  52 } __packed __aligned(PAGE_SIZE);
  53
  54 static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
  55 static struct sclp_ipl_info sclp_ipl_info;
  56
  57 struct sclp_info sclp;
  58 EXPORT_SYMBOL(sclp);
  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_core_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.has_sprp = !!(sccb->fac84 & 0x02);
 113         sclp.has_core_type = !!(sccb->fac84 & 0x01);
 114         sclp.has_esca = !!(sccb->fac116 & 0x08);
 115         sclp.has_hvs = !!(sccb->fac119 & 0x80);
 116         if (sccb->fac85 & 0x02)
 117                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
 118         sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 119         sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 120         sclp.rzm <<= 20;
 121         sclp.ibc = sccb->ibc;
 122
 123         if (!sccb->hcpua) {
 124                 if (MACHINE_IS_VM)
 125                         sclp.max_cores = 64;
 126                 else
 127                         sclp.max_cores = sccb->ncpurl;
 128         } else {
 129                 sclp.max_cores = sccb->hcpua + 1;
 130         }
 131
 132         boot_cpu_address = stap();
 133         cpue = (void *)sccb + sccb->cpuoff;
 134         for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
 135                 if (boot_cpu_address != cpue->core_id)
 136                         continue;
 137                 sclp.has_siif = cpue->siif;
 138                 sclp.has_sigpif = cpue->sigpif;
 139                 break;
 140         }
 141
 142         /* Save IPL information */
 143         sclp_ipl_info.is_valid = 1;
 144         if (sccb->flags & 0x2)
 145                 sclp_ipl_info.has_dump = 1;
 146         memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
 147
 148         sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
 149         sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
 150         sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
 151 }
 152
 153 /*
 154  * This function will be called after sclp_facilities_detect(), which gets
 155  * called from early.c code. The sclp_facilities_detect() function retrieves
 156  * and saves the IPL information.
 157  */
 158 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 159 {
 160         *info = sclp_ipl_info;
 161 }
 162
 163 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
 164 {
 165         int rc;
 166
 167         do {
 168                 rc = sclp_cmd_sync_early(cmd, sccb);
 169         } while (rc == -EBUSY);
 170
 171         if (rc)
 172                 return -EIO;
 173         if (((struct sccb_header *) sccb)->response_code != 0x0020)
 174                 return -EIO;
 175         return 0;
 176 }
 177
 178 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
 179 {
 180         memset(sccb, 0, sizeof(*sccb));
 181
 182         sccb->hdr.length = sizeof(*sccb);
 183         sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
 184         sccb->evbuf.hdr.type = EVTYP_SDIAS;
 185         sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
 186         sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
 187         sccb->evbuf.event_id = 4712;
 188         sccb->evbuf.dbs = 1;
 189 }
 190
 191 static int __init sclp_set_event_mask(struct init_sccb *sccb,
 192                                       unsigned long receive_mask,
 193                                       unsigned long send_mask)
 194 {
 195         memset(sccb, 0, sizeof(*sccb));
 196         sccb->header.length = sizeof(*sccb);
 197         sccb->mask_length = sizeof(sccb_mask_t);
 198         sccb->receive_mask = receive_mask;
 199         sccb->send_mask = send_mask;
 200         return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 201 }
 202
 203 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
 204 {
 205         sccb_init_eq_size(sccb);
 206         if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
 207                 return -EIO;
 208         if (sccb->evbuf.blk_cnt == 0)
 209                 return 0;
 210         return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
 211 }
 212
 213 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
 214 {
 215         memset(sccb, 0, PAGE_SIZE);
 216         sccb->length = PAGE_SIZE;
 217         if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
 218                 return -EIO;
 219         if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
 220                 return 0;
 221         return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
 222 }
 223
 224 static void __init sclp_hsa_size_detect(void *sccb)
 225 {
 226         long size;
 227
 228         /* First try synchronous interface (LPAR) */
 229         if (sclp_set_event_mask(sccb, 0, 0x40000010))
 230                 return;
 231         size = sclp_hsa_size_init(sccb);
 232         if (size < 0)
 233                 return;
 234         if (size != 0)
 235                 goto out;
 236         /* Then try asynchronous interface (z/VM) */
 237         if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
 238                 return;
 239         size = sclp_hsa_size_init(sccb);
 240         if (size < 0)
 241                 return;
 242         size = sclp_hsa_copy_wait(sccb);
 243         if (size < 0)
 244                 return;
 245 out:
 246         sclp.hsa_size = size;
 247 }
 248
 249 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
 250 {
 251         if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
 252                 return 0;
 253         if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
 254                 return 0;
 255         return 1;
 256 }
 257
 258 static void __init sclp_console_detect(struct init_sccb *sccb)
 259 {
 260         if (sccb->header.response_code != 0x20)
 261                 return;
 262
 263         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 264                 sclp.has_vt220 = 1;
 265
 266         if (sclp_con_check_linemode(sccb))
 267                 sclp.has_linemode = 1;
 268 }
 269
 270 void __init sclp_early_detect(void)
 271 {
 272         void *sccb = &sccb_early;
 273
 274         sclp_facilities_detect(sccb);
 275         sclp_hsa_size_detect(sccb);
 276
 277         /* Turn off SCLP event notifications.  Also save remote masks in the
 278          * sccb.  These are sufficient to detect sclp console capabilities.
 279          */
 280         sclp_set_event_mask(sccb, 0, 0);
 281         sclp_console_detect(sccb);
 282 }