drivers/s390/char/sclp_cmd.c

   1 /*
   2  *  drivers/s390/char/sclp_cmd.c
   3  *
   4  *    Copyright IBM Corp. 2007
   5  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
   6  */
   7
   8 #include <linux/completion.h>
   9 #include <linux/init.h>
  10 #include <linux/errno.h>
  11 #include <linux/slab.h>
  12 #include <linux/string.h>
  13 #include <asm/sclp.h>
  14 #include "sclp.h"
  15
  16 #define TAG     "sclp_cmd: "
  17
  18 #define SCLP_CMDW_READ_SCP_INFO         0x00020001
  19 #define SCLP_CMDW_READ_SCP_INFO_FORCED  0x00120001
  20
  21 struct read_info_sccb {
  22         struct  sccb_header header;     /* 0-7 */
  23         u16     rnmax;                  /* 8-9 */
  24         u8      rnsize;                 /* 10 */
  25         u8      _reserved0[24 - 11];    /* 11-15 */
  26         u8      loadparm[8];            /* 24-31 */
  27         u8      _reserved1[48 - 32];    /* 32-47 */
  28         u64     facilities;             /* 48-55 */
  29         u8      _reserved2[84 - 56];    /* 56-83 */
  30         u8      fac84;                  /* 84 */
  31         u8      _reserved3[91 - 85];    /* 85-90 */
  32         u8      flags;                  /* 91 */
  33         u8      _reserved4[100 - 92];   /* 92-99 */
  34         u32     rnsize2;                /* 100-103 */
  35         u64     rnmax2;                 /* 104-111 */
  36         u8      _reserved5[4096 - 112]; /* 112-4095 */
  37 } __attribute__((packed, aligned(PAGE_SIZE)));
  38
  39 static struct read_info_sccb __initdata early_read_info_sccb;
  40 static int __initdata early_read_info_sccb_valid;
  41
  42 u64 sclp_facilities;
  43 static u8 sclp_fac84;
  44
  45 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  46 {
  47         int rc;
  48
  49         __ctl_set_bit(0, 9);
  50         rc = sclp_service_call(cmd, sccb);
  51         if (rc)
  52                 goto out;
  53         __load_psw_mask(PSW_BASE_BITS | PSW_MASK_EXT |
  54                         PSW_MASK_WAIT | PSW_DEFAULT_KEY);
  55         local_irq_disable();
  56 out:
  57         /* Contents of the sccb might have changed. */
  58         barrier();
  59         __ctl_clear_bit(0, 9);
  60         return rc;
  61 }
  62
  63 void __init sclp_read_info_early(void)
  64 {
  65         int rc;
  66         int i;
  67         struct read_info_sccb *sccb;
  68         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  69                                   SCLP_CMDW_READ_SCP_INFO};
  70
  71         sccb = &early_read_info_sccb;
  72         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  73                 do {
  74                         memset(sccb, 0, sizeof(*sccb));
  75                         sccb->header.length = sizeof(*sccb);
  76                         sccb->header.control_mask[2] = 0x80;
  77                         rc = sclp_cmd_sync_early(commands[i], sccb);
  78                 } while (rc == -EBUSY);
  79
  80                 if (rc)
  81                         break;
  82                 if (sccb->header.response_code == 0x10) {
  83                         early_read_info_sccb_valid = 1;
  84                         break;
  85                 }
  86                 if (sccb->header.response_code != 0x1f0)
  87                         break;
  88         }
  89 }
  90
  91 void __init sclp_facilities_detect(void)
  92 {
  93         if (!early_read_info_sccb_valid)
  94                 return;
  95         sclp_facilities = early_read_info_sccb.facilities;
  96         sclp_fac84 = early_read_info_sccb.fac84;
  97 }
  98
  99 unsigned long long __init sclp_memory_detect(void)
 100 {
 101         unsigned long long memsize;
 102         struct read_info_sccb *sccb;
 103
 104         if (!early_read_info_sccb_valid)
 105                 return 0;
 106         sccb = &early_read_info_sccb;
 107         if (sccb->rnsize)
 108                 memsize = sccb->rnsize << 20;
 109         else
 110                 memsize = sccb->rnsize2 << 20;
 111         if (sccb->rnmax)
 112                 memsize *= sccb->rnmax;
 113         else
 114                 memsize *= sccb->rnmax2;
 115         return memsize;
 116 }
 117
 118 /*
 119  * This function will be called after sclp_memory_detect(), which gets called
 120  * early from early.c code. Therefore the sccb should have valid contents.
 121  */
 122 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 123 {
 124         struct read_info_sccb *sccb;
 125
 126         if (!early_read_info_sccb_valid)
 127                 return;
 128         sccb = &early_read_info_sccb;
 129         info->is_valid = 1;
 130         if (sccb->flags & 0x2)
 131                 info->has_dump = 1;
 132         memcpy(&info->loadparm, &sccb->loadparm, LOADPARM_LEN);
 133 }
 134
 135 static void sclp_sync_callback(struct sclp_req *req, void *data)
 136 {
 137         struct completion *completion = data;
 138
 139         complete(completion);
 140 }
 141
 142 static int do_sync_request(sclp_cmdw_t cmd, void *sccb)
 143 {
 144         struct completion completion;
 145         struct sclp_req *request;
 146         int rc;
 147
 148         request = kzalloc(sizeof(*request), GFP_KERNEL);
 149         if (!request)
 150                 return -ENOMEM;
 151         request->command = cmd;
 152         request->sccb = sccb;
 153         request->status = SCLP_REQ_FILLED;
 154         request->callback = sclp_sync_callback;
 155         request->callback_data = &completion;
 156         init_completion(&completion);
 157
 158         /* Perform sclp request. */
 159         rc = sclp_add_request(request);
 160         if (rc)
 161                 goto out;
 162         wait_for_completion(&completion);
 163
 164         /* Check response. */
 165         if (request->status != SCLP_REQ_DONE) {
 166                 printk(KERN_WARNING TAG "sync request failed "
 167                        "(cmd=0x%08x, status=0x%02x)\n", cmd, request->status);
 168                 rc = -EIO;
 169         }
 170 out:
 171         kfree(request);
 172         return rc;
 173 }
 174
 175 /*
 176  * CPU configuration related functions.
 177  */
 178
 179 #define SCLP_CMDW_READ_CPU_INFO         0x00010001
 180 #define SCLP_CMDW_CONFIGURE_CPU         0x00110001
 181 #define SCLP_CMDW_DECONFIGURE_CPU       0x00100001
 182
 183 struct read_cpu_info_sccb {
 184         struct  sccb_header header;
 185         u16     nr_configured;
 186         u16     offset_configured;
 187         u16     nr_standby;
 188         u16     offset_standby;
 189         u8      reserved[4096 - 16];
 190 } __attribute__((packed, aligned(PAGE_SIZE)));
 191
 192 static struct read_cpu_info_sccb __initdata early_read_cpu_info_sccb;
 193 static struct sclp_cpu_info __initdata sclp_cpu_info;
 194
 195 static void sclp_fill_cpu_info(struct sclp_cpu_info *info,
 196                                struct read_cpu_info_sccb *sccb)
 197 {
 198         char *page = (char *) sccb;
 199
 200         memset(info, 0, sizeof(*info));
 201         info->configured = sccb->nr_configured;
 202         info->standby = sccb->nr_standby;
 203         info->combined = sccb->nr_configured + sccb->nr_standby;
 204         info->has_cpu_type = sclp_fac84 & 0x1;
 205         memcpy(&info->cpu, page + sccb->offset_configured,
 206                info->combined * sizeof(struct sclp_cpu_entry));
 207 }
 208
 209 void __init sclp_read_cpu_info_early(void)
 210 {
 211         int rc;
 212         struct read_cpu_info_sccb *sccb;
 213
 214         if (!SCLP_HAS_CPU_INFO)
 215                 return;
 216
 217         sccb = &early_read_cpu_info_sccb;
 218         do {
 219                 memset(sccb, 0, sizeof(*sccb));
 220                 sccb->header.length = sizeof(*sccb);
 221                 rc = sclp_cmd_sync_early(SCLP_CMDW_READ_CPU_INFO, sccb);
 222         } while (rc == -EBUSY);
 223
 224         if (rc)
 225                 return;
 226         if (sccb->header.response_code != 0x10)
 227                 return;
 228         sclp_fill_cpu_info(&sclp_cpu_info, sccb);
 229 }
 230
 231 static int __init sclp_get_cpu_info_early(struct sclp_cpu_info *info)
 232 {
 233         if (!SCLP_HAS_CPU_INFO)
 234                 return -EOPNOTSUPP;
 235         *info = sclp_cpu_info;
 236         return 0;
 237 }
 238
 239 static int sclp_get_cpu_info_late(struct sclp_cpu_info *info)
 240 {
 241         int rc;
 242         struct read_cpu_info_sccb *sccb;
 243
 244         if (!SCLP_HAS_CPU_INFO)
 245                 return -EOPNOTSUPP;
 246         sccb = (struct read_cpu_info_sccb *)  __get_free_page(GFP_KERNEL
 247                                                               | GFP_DMA);
 248         if (!sccb)
 249                 return -ENOMEM;
 250         memset(sccb, 0, sizeof(*sccb));
 251         sccb->header.length = sizeof(*sccb);
 252         rc = do_sync_request(SCLP_CMDW_READ_CPU_INFO, sccb);
 253         if (rc)
 254                 goto out;
 255         if (sccb->header.response_code != 0x0010) {
 256                 printk(KERN_WARNING TAG "readcpuinfo failed "
 257                        "(response=0x%04x)\n", sccb->header.response_code);
 258                 rc = -EIO;
 259                 goto out;
 260         }
 261         sclp_fill_cpu_info(info, sccb);
 262 out:
 263         free_page((unsigned long) sccb);
 264         return rc;
 265 }
 266
 267 int __init_refok sclp_get_cpu_info(struct sclp_cpu_info *info)
 268 {
 269         if (slab_is_available())
 270                 return sclp_get_cpu_info_late(info);
 271         return sclp_get_cpu_info_early(info);
 272 }
 273
 274 struct cpu_configure_sccb {
 275         struct sccb_header header;
 276 } __attribute__((packed, aligned(8)));
 277
 278 static int do_cpu_configure(sclp_cmdw_t cmd)
 279 {
 280         struct cpu_configure_sccb *sccb;
 281         int rc;
 282
 283         if (!SCLP_HAS_CPU_RECONFIG)
 284                 return -EOPNOTSUPP;
 285         /*
 286          * This is not going to cross a page boundary since we force
 287          * kmalloc to have a minimum alignment of 8 bytes on s390.
 288          */
 289         sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
 290         if (!sccb)
 291                 return -ENOMEM;
 292         sccb->header.length = sizeof(*sccb);
 293         rc = do_sync_request(cmd, sccb);
 294         if (rc)
 295                 goto out;
 296         switch (sccb->header.response_code) {
 297         case 0x0020:
 298         case 0x0120:
 299                 break;
 300         default:
 301                 printk(KERN_WARNING TAG "configure cpu failed (cmd=0x%08x, "
 302                        "response=0x%04x)\n", cmd, sccb->header.response_code);
 303                 rc = -EIO;
 304                 break;
 305         }
 306 out:
 307         kfree(sccb);
 308         return rc;
 309 }
 310
 311 int sclp_cpu_configure(u8 cpu)
 312 {
 313         return do_cpu_configure(SCLP_CMDW_CONFIGURE_CPU | cpu << 8);
 314 }
 315
 316 int sclp_cpu_deconfigure(u8 cpu)
 317 {
 318         return do_cpu_configure(SCLP_CMDW_DECONFIGURE_CPU | cpu << 8);
 319 }