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