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 char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
  39 static unsigned int sclp_con_has_vt220 __initdata;
  40 static unsigned int sclp_con_has_linemode __initdata;
  41 static unsigned long sclp_hsa_size;
  42 static struct sclp_ipl_info sclp_ipl_info;
  43
  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 int __init sclp_read_info_early(struct read_info_sccb *sccb)
  68 {
  69         int rc, i;
  70         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  71                                   SCLP_CMDW_READ_SCP_INFO};
  72
  73         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  74                 do {
  75                         memset(sccb, 0, sizeof(*sccb));
  76                         sccb->header.length = sizeof(*sccb);
  77                         sccb->header.function_code = 0x80;
  78                         sccb->header.control_mask[2] = 0x80;
  79                         rc = sclp_cmd_sync_early(commands[i], sccb);
  80                 } while (rc == -EBUSY);
  81
  82                 if (rc)
  83                         break;
  84                 if (sccb->header.response_code == 0x10)
  85                         return 0;
  86                 if (sccb->header.response_code != 0x1f0)
  87                         break;
  88         }
  89         return -EIO;
  90 }
  91
  92 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
  93 {
  94         if (sclp_read_info_early(sccb))
  95                 return;
  96
  97         sclp_facilities = sccb->facilities;
  98         sclp_fac84 = sccb->fac84;
  99         if (sccb->fac85 & 0x02)
 100                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
 101         sclp_rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 102         sclp_rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 103         sclp_rzm <<= 20;
 104
 105         /* Save IPL information */
 106         sclp_ipl_info.is_valid = 1;
 107         if (sccb->flags & 0x2)
 108                 sclp_ipl_info.has_dump = 1;
 109         memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
 110 }
 111
 112 bool __init sclp_has_linemode(void)
 113 {
 114         return !!sclp_con_has_linemode;
 115 }
 116
 117 bool __init sclp_has_vt220(void)
 118 {
 119         return !!sclp_con_has_vt220;
 120 }
 121
 122 unsigned long long sclp_get_rnmax(void)
 123 {
 124         return sclp_rnmax;
 125 }
 126
 127 unsigned long long sclp_get_rzm(void)
 128 {
 129         return sclp_rzm;
 130 }
 131
 132 /*
 133  * This function will be called after sclp_facilities_detect(), which gets
 134  * called from early.c code. The sclp_facilities_detect() function retrieves
 135  * and saves the IPL information.
 136  */
 137 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 138 {
 139         *info = sclp_ipl_info;
 140 }
 141
 142 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
 143 {
 144         int rc;
 145
 146         do {
 147                 rc = sclp_cmd_sync_early(cmd, sccb);
 148         } while (rc == -EBUSY);
 149
 150         if (rc)
 151                 return -EIO;
 152         if (((struct sccb_header *) sccb)->response_code != 0x0020)
 153                 return -EIO;
 154         return 0;
 155 }
 156
 157 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
 158 {
 159         memset(sccb, 0, sizeof(*sccb));
 160
 161         sccb->hdr.length = sizeof(*sccb);
 162         sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
 163         sccb->evbuf.hdr.type = EVTYP_SDIAS;
 164         sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
 165         sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
 166         sccb->evbuf.event_id = 4712;
 167         sccb->evbuf.dbs = 1;
 168 }
 169
 170 static int __init sclp_set_event_mask(struct init_sccb *sccb,
 171                                       unsigned long receive_mask,
 172                                       unsigned long send_mask)
 173 {
 174         memset(sccb, 0, sizeof(*sccb));
 175         sccb->header.length = sizeof(*sccb);
 176         sccb->mask_length = sizeof(sccb_mask_t);
 177         sccb->receive_mask = receive_mask;
 178         sccb->send_mask = send_mask;
 179         return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 180 }
 181
 182 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
 183 {
 184         sccb_init_eq_size(sccb);
 185         if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
 186                 return -EIO;
 187         if (sccb->evbuf.blk_cnt != 0)
 188                 return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
 189         return 0;
 190 }
 191
 192 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
 193 {
 194         memset(sccb, 0, PAGE_SIZE);
 195         sccb->length = PAGE_SIZE;
 196         if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
 197                 return -EIO;
 198         return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
 199 }
 200
 201 unsigned long sclp_get_hsa_size(void)
 202 {
 203         return sclp_hsa_size;
 204 }
 205
 206 static void __init sclp_hsa_size_detect(void *sccb)
 207 {
 208         long size;
 209
 210         /* First try synchronous interface (LPAR) */
 211         if (sclp_set_event_mask(sccb, 0, 0x40000010))
 212                 return;
 213         size = sclp_hsa_size_init(sccb);
 214         if (size < 0)
 215                 return;
 216         if (size != 0)
 217                 goto out;
 218         /* Then try asynchronous interface (z/VM) */
 219         if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
 220                 return;
 221         size = sclp_hsa_size_init(sccb);
 222         if (size < 0)
 223                 return;
 224         size = sclp_hsa_copy_wait(sccb);
 225         if (size < 0)
 226                 return;
 227 out:
 228         sclp_hsa_size = size;
 229 }
 230
 231 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
 232 {
 233         if (!(sccb->sclp_send_mask & (EVTYP_OPCMD_MASK | EVTYP_PMSGCMD_MASK)))
 234                 return 0;
 235         if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
 236                 return 0;
 237         return 1;
 238 }
 239
 240 static void __init sclp_console_detect(struct init_sccb *sccb)
 241 {
 242         if (sccb->header.response_code != 0x20)
 243                 return;
 244
 245         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 246                 sclp_con_has_vt220 = 1;
 247
 248         if (sclp_con_check_linemode(sccb))
 249                 sclp_con_has_linemode = 1;
 250 }
 251
 252 void __init sclp_early_detect(void)
 253 {
 254         void *sccb = &sccb_early;
 255
 256         sclp_facilities_detect(sccb);
 257         sclp_hsa_size_detect(sccb);
 258
 259         /* Turn off SCLP event notifications.  Also save remote masks in the
 260          * sccb.  These are sufficient to detect sclp console capabilities.
 261          */
 262         sclp_set_event_mask(sccb, 0, 0);
 263         sclp_console_detect(sccb);
 264 }