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