arch/ia64/kernel/esi.c

   1 /*
   2  * Extensible SAL Interface (ESI) support routines.
   3  *
   4  * Copyright (C) 2006 Hewlett-Packard Co
   5  *      Alex Williamson <alex.williamson@hp.com>
   6  */
   7 #include <linux/kernel.h>
   8 #include <linux/init.h>
   9 #include <linux/module.h>
  10 #include <linux/string.h>
  11
  12 #include <asm/esi.h>
  13 #include <asm/sal.h>
  14
  15 MODULE_AUTHOR("Alex Williamson <alex.williamson@hp.com>");
  16 MODULE_DESCRIPTION("Extensible SAL Interface (ESI) support");
  17 MODULE_LICENSE("GPL");
  18
  19 #define MODULE_NAME     "esi"
  20
  21 #define ESI_TABLE_GUID                                  \
  22     EFI_GUID(0x43EA58DC, 0xCF28, 0x4b06, 0xB3,          \
  23              0x91, 0xB7, 0x50, 0x59, 0x34, 0x2B, 0xD4)
  24
  25 enum esi_systab_entry_type {
  26         ESI_DESC_ENTRY_POINT = 0
  27 };
  28
  29 /*
  30  * Entry type:  Size:
  31  *      0       48
  32  */
  33 #define ESI_DESC_SIZE(type)     "\060"[(unsigned) (type)]
  34
  35 typedef struct ia64_esi_desc_entry_point {
  36         u8 type;
  37         u8 reserved1[15];
  38         u64 esi_proc;
  39         u64 gp;
  40         efi_guid_t guid;
  41 } ia64_esi_desc_entry_point_t;
  42
  43 struct pdesc {
  44         void *addr;
  45         void *gp;
  46 };
  47
  48 static struct ia64_sal_systab *esi_systab;
  49
  50 static int __init esi_init (void)
  51 {
  52         efi_config_table_t *config_tables;
  53         struct ia64_sal_systab *systab;
  54         unsigned long esi = 0;
  55         char *p;
  56         int i;
  57
  58         config_tables = __va(efi.systab->tables);
  59
  60         for (i = 0; i < (int) efi.systab->nr_tables; ++i) {
  61                 if (efi_guidcmp(config_tables[i].guid, ESI_TABLE_GUID) == 0) {
  62                         esi = config_tables[i].table;
  63                         break;
  64                 }
  65         }
  66
  67         if (!esi)
  68                 return -ENODEV;
  69
  70         systab = __va(esi);
  71
  72         if (strncmp(systab->signature, "ESIT", 4) != 0) {
  73                 printk(KERN_ERR "bad signature in ESI system table!");
  74                 return -ENODEV;
  75         }
  76
  77         p = (char *) (systab + 1);
  78         for (i = 0; i < systab->entry_count; i++) {
  79                 /*
  80                  * The first byte of each entry type contains the type
  81                  * descriptor.
  82                  */
  83                 switch (*p) {
  84                       case ESI_DESC_ENTRY_POINT:
  85                         break;
  86                       default:
  87                         printk(KERN_WARNING "Unknown table type %d found in "
  88                                "ESI table, ignoring rest of table\n", *p);
  89                         return -ENODEV;
  90                 }
  91
  92                 p += ESI_DESC_SIZE(*p);
  93         }
  94
  95         esi_systab = systab;
  96         return 0;
  97 }
  98
  99
 100 int ia64_esi_call (efi_guid_t guid, struct ia64_sal_retval *isrvp,
 101                    enum esi_proc_type proc_type, u64 func,
 102                    u64 arg1, u64 arg2, u64 arg3, u64 arg4, u64 arg5, u64 arg6,
 103                    u64 arg7)
 104 {
 105         struct ia64_fpreg fr[6];
 106         unsigned long flags = 0;
 107         int i;
 108         char *p;
 109
 110         if (!esi_systab)
 111                 return -1;
 112
 113         p = (char *) (esi_systab + 1);
 114         for (i = 0; i < esi_systab->entry_count; i++) {
 115                 if (*p == ESI_DESC_ENTRY_POINT) {
 116                         ia64_esi_desc_entry_point_t *esi = (void *)p;
 117                         if (!efi_guidcmp(guid, esi->guid)) {
 118                                 ia64_sal_handler esi_proc;
 119                                 struct pdesc pdesc;
 120
 121                                 pdesc.addr = __va(esi->esi_proc);
 122                                 pdesc.gp = __va(esi->gp);
 123
 124                                 esi_proc = (ia64_sal_handler) &pdesc;
 125
 126                                 ia64_save_scratch_fpregs(fr);
 127                                 if (proc_type == ESI_PROC_SERIALIZED)
 128                                         spin_lock_irqsave(&sal_lock, flags);
 129                                 else if (proc_type == ESI_PROC_MP_SAFE)
 130                                         local_irq_save(flags);
 131                                 else
 132                                         preempt_disable();
 133                                 *isrvp = (*esi_proc)(func, arg1, arg2, arg3,
 134                                                      arg4, arg5, arg6, arg7);
 135                                 if (proc_type == ESI_PROC_SERIALIZED)
 136                                         spin_unlock_irqrestore(&sal_lock,
 137                                                                flags);
 138                                 else if (proc_type == ESI_PROC_MP_SAFE)
 139                                         local_irq_restore(flags);
 140                                 else
 141                                         preempt_enable();
 142                                 ia64_load_scratch_fpregs(fr);
 143                                 return 0;
 144                         }
 145                 }
 146                 p += ESI_DESC_SIZE(*p);
 147         }
 148         return -1;
 149 }
 150 EXPORT_SYMBOL_GPL(ia64_esi_call);
 151
 152 int ia64_esi_call_phys (efi_guid_t guid, struct ia64_sal_retval *isrvp,
 153                         u64 func, u64 arg1, u64 arg2, u64 arg3, u64 arg4,
 154                         u64 arg5, u64 arg6, u64 arg7)
 155 {
 156         struct ia64_fpreg fr[6];
 157         unsigned long flags;
 158         u64 esi_params[8];
 159         char *p;
 160         int i;
 161
 162         if (!esi_systab)
 163                 return -1;
 164
 165         p = (char *) (esi_systab + 1);
 166         for (i = 0; i < esi_systab->entry_count; i++) {
 167                 if (*p == ESI_DESC_ENTRY_POINT) {
 168                         ia64_esi_desc_entry_point_t *esi = (void *)p;
 169                         if (!efi_guidcmp(guid, esi->guid)) {
 170                                 ia64_sal_handler esi_proc;
 171                                 struct pdesc pdesc;
 172
 173                                 pdesc.addr = (void *)esi->esi_proc;
 174                                 pdesc.gp = (void *)esi->gp;
 175
 176                                 esi_proc = (ia64_sal_handler) &pdesc;
 177
 178                                 esi_params[0] = func;
 179                                 esi_params[1] = arg1;
 180                                 esi_params[2] = arg2;
 181                                 esi_params[3] = arg3;
 182                                 esi_params[4] = arg4;
 183                                 esi_params[5] = arg5;
 184                                 esi_params[6] = arg6;
 185                                 esi_params[7] = arg7;
 186                                 ia64_save_scratch_fpregs(fr);
 187                                 spin_lock_irqsave(&sal_lock, flags);
 188                                 *isrvp = esi_call_phys(esi_proc, esi_params);
 189                                 spin_unlock_irqrestore(&sal_lock, flags);
 190                                 ia64_load_scratch_fpregs(fr);
 191                                 return 0;
 192                         }
 193                 }
 194                 p += ESI_DESC_SIZE(*p);
 195         }
 196         return -1;
 197 }
 198 EXPORT_SYMBOL_GPL(ia64_esi_call_phys);
 199
 200 static void __exit esi_exit (void)
 201 {
 202 }
 203
 204 module_init(esi_init);
 205 module_exit(esi_exit);  /* makes module removable... */