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[24 - 11];    /* 11-15 */
  24         u8      loadparm[8];            /* 24-31 */
  25         u8      _reserved1[48 - 32];    /* 32-47 */
  26         u64     facilities;             /* 48-55 */
  27         u8      _reserved2[84 - 56];    /* 56-83 */
  28         u8      fac84;                  /* 84 */
  29         u8      fac85;                  /* 85 */
  30         u8      _reserved3[91 - 86];    /* 86-90 */
  31         u8      flags;                  /* 91 */
  32         u8      _reserved4[100 - 92];   /* 92-99 */
  33         u32     rnsize2;                /* 100-103 */
  34         u64     rnmax2;                 /* 104-111 */
  35         u8      _reserved5[4096 - 112]; /* 112-4095 */
  36 } __packed __aligned(PAGE_SIZE);
  37
  38 static __initdata struct init_sccb early_event_mask_sccb __aligned(PAGE_SIZE);
  39 static __initdata struct read_info_sccb early_read_info_sccb;
  40 static __initdata char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE);
  41 static unsigned long sclp_hsa_size;
  42
  43 __initdata int sclp_early_read_info_sccb_valid;
  44 u64 sclp_facilities;
  45 u8 sclp_fac84;
  46 unsigned long long sclp_rzm;
  47 unsigned long long sclp_rnmax;
  48
  49 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  50 {
  51         int rc;
  52
  53         __ctl_set_bit(0, 9);
  54         rc = sclp_service_call(cmd, sccb);
  55         if (rc)
  56                 goto out;
  57         __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
  58                         PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
  59         local_irq_disable();
  60 out:
  61         /* Contents of the sccb might have changed. */
  62         barrier();
  63         __ctl_clear_bit(0, 9);
  64         return rc;
  65 }
  66
  67 static void __init sclp_read_info_early(void)
  68 {
  69         int rc;
  70         int i;
  71         struct read_info_sccb *sccb;
  72         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  73                                   SCLP_CMDW_READ_SCP_INFO};
  74
  75         sccb = &early_read_info_sccb;
  76         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  77                 do {
  78                         memset(sccb, 0, sizeof(*sccb));
  79                         sccb->header.length = sizeof(*sccb);
  80                         sccb->header.function_code = 0x80;
  81                         sccb->header.control_mask[2] = 0x80;
  82                         rc = sclp_cmd_sync_early(commands[i], sccb);
  83                 } while (rc == -EBUSY);
  84
  85                 if (rc)
  86                         break;
  87                 if (sccb->header.response_code == 0x10) {
  88                         sclp_early_read_info_sccb_valid = 1;
  89                         break;
  90                 }
  91                 if (sccb->header.response_code != 0x1f0)
  92                         break;
  93         }
  94 }
  95
  96 static void __init sclp_event_mask_early(void)
  97 {
  98         struct init_sccb *sccb = &early_event_mask_sccb;
  99         int rc;
 100
 101         do {
 102                 memset(sccb, 0, sizeof(*sccb));
 103                 sccb->header.length = sizeof(*sccb);
 104                 sccb->mask_length = sizeof(sccb_mask_t);
 105                 rc = sclp_cmd_sync_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 106         } while (rc == -EBUSY);
 107 }
 108
 109 void __init sclp_facilities_detect(void)
 110 {
 111         struct read_info_sccb *sccb;
 112
 113         sclp_read_info_early();
 114         if (!sclp_early_read_info_sccb_valid)
 115                 return;
 116
 117         sccb = &early_read_info_sccb;
 118         sclp_facilities = sccb->facilities;
 119         sclp_fac84 = sccb->fac84;
 120         if (sccb->fac85 & 0x02)
 121                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
 122         sclp_rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 123         sclp_rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 124         sclp_rzm <<= 20;
 125
 126         sclp_event_mask_early();
 127 }
 128
 129 bool __init sclp_has_linemode(void)
 130 {
 131         struct init_sccb *sccb = &early_event_mask_sccb;
 132
 133         if (sccb->header.response_code != 0x20)
 134                 return 0;
 135         if (!(sccb->sclp_send_mask & (EVTYP_OPCMD_MASK | EVTYP_PMSGCMD_MASK)))
 136                 return 0;
 137         if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
 138                 return 0;
 139         return 1;
 140 }
 141
 142 bool __init sclp_has_vt220(void)
 143 {
 144         struct init_sccb *sccb = &early_event_mask_sccb;
 145
 146         if (sccb->header.response_code != 0x20)
 147                 return 0;
 148         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 149                 return 1;
 150         return 0;
 151 }
 152
 153 unsigned long long sclp_get_rnmax(void)
 154 {
 155         return sclp_rnmax;
 156 }
 157
 158 unsigned long long sclp_get_rzm(void)
 159 {
 160         return sclp_rzm;
 161 }
 162
 163 /*
 164  * This function will be called after sclp_facilities_detect(), which gets
 165  * called from early.c code. Therefore the sccb should have valid contents.
 166  */
 167 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 168 {
 169         struct read_info_sccb *sccb;
 170
 171         if (!sclp_early_read_info_sccb_valid)
 172                 return;
 173         sccb = &early_read_info_sccb;
 174         info->is_valid = 1;
 175         if (sccb->flags & 0x2)
 176                 info->has_dump = 1;
 177         memcpy(&info->loadparm, &sccb->loadparm, LOADPARM_LEN);
 178 }
 179
 180 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
 181 {
 182         int rc;
 183
 184         do {
 185                 rc = sclp_cmd_sync_early(cmd, sccb);
 186         } while (rc == -EBUSY);
 187
 188         if (rc)
 189                 return -EIO;
 190         if (((struct sccb_header *) sccb)->response_code != 0x0020)
 191                 return -EIO;
 192         return 0;
 193 }
 194
 195 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
 196 {
 197         memset(sccb, 0, sizeof(*sccb));
 198
 199         sccb->hdr.length = sizeof(*sccb);
 200         sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
 201         sccb->evbuf.hdr.type = EVTYP_SDIAS;
 202         sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
 203         sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
 204         sccb->evbuf.event_id = 4712;
 205         sccb->evbuf.dbs = 1;
 206 }
 207
 208 static int __init sclp_set_event_mask(unsigned long receive_mask,
 209                                       unsigned long send_mask)
 210 {
 211         struct init_sccb *sccb = (void *) &sccb_early;
 212
 213         memset(sccb, 0, sizeof(*sccb));
 214         sccb->header.length = sizeof(*sccb);
 215         sccb->mask_length = sizeof(sccb_mask_t);
 216         sccb->receive_mask = receive_mask;
 217         sccb->send_mask = send_mask;
 218         return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 219 }
 220
 221 static long __init sclp_hsa_size_init(void)
 222 {
 223         struct sdias_sccb *sccb = (void *) &sccb_early;
 224
 225         sccb_init_eq_size(sccb);
 226         if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
 227                 return -EIO;
 228         if (sccb->evbuf.blk_cnt != 0)
 229                 return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
 230         return 0;
 231 }
 232
 233 static long __init sclp_hsa_copy_wait(void)
 234 {
 235         struct sccb_header *sccb = (void *) &sccb_early;
 236
 237         memset(sccb, 0, PAGE_SIZE);
 238         sccb->length = PAGE_SIZE;
 239         if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
 240                 return -EIO;
 241         return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
 242 }
 243
 244 unsigned long sclp_get_hsa_size(void)
 245 {
 246         return sclp_hsa_size;
 247 }
 248
 249 void __init sclp_hsa_size_detect(void)
 250 {
 251         long size;
 252
 253         /* First try synchronous interface (LPAR) */
 254         if (sclp_set_event_mask(0, 0x40000010))
 255                 return;
 256         size = sclp_hsa_size_init();
 257         if (size < 0)
 258                 return;
 259         if (size != 0)
 260                 goto out;
 261         /* Then try asynchronous interface (z/VM) */
 262         if (sclp_set_event_mask(0x00000010, 0x40000010))
 263                 return;
 264         size = sclp_hsa_size_init();
 265         if (size < 0)
 266                 return;
 267         size = sclp_hsa_copy_wait();
 268         if (size < 0)
 269                 return;
 270 out:
 271         sclp_set_event_mask(0, 0);
 272         sclp_hsa_size = size;
 273 }