arch/ia64/kernel/esi.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Extensible SAL Interface (ESI) support routines.
   4  *
   5  * Copyright (C) 2006 Hewlett-Packard Co
   6  *      Alex Williamson <alex.williamson@hp.com>
   7  */
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11 #include <linux/string.h>
  12
  13 #include <asm/esi.h>
  14 #include <asm/sal.h>
  15
  16 MODULE_AUTHOR("Alex Williamson <alex.williamson@hp.com>");
  17 MODULE_DESCRIPTION("Extensible SAL Interface (ESI) support");
  18 MODULE_LICENSE("GPL");
  19
  20 #define MODULE_NAME     "esi"
  21
  22 enum esi_systab_entry_type {
  23         ESI_DESC_ENTRY_POINT = 0
  24 };
  25
  26 /*
  27  * Entry type:  Size:
  28  *      0       48
  29  */
  30 #define ESI_DESC_SIZE(type)     "\060"[(unsigned) (type)]
  31
  32 typedef struct ia64_esi_desc_entry_point {
  33         u8 type;
  34         u8 reserved1[15];
  35         u64 esi_proc;
  36         u64 gp;
  37         efi_guid_t guid;
  38 } ia64_esi_desc_entry_point_t;
  39
  40 struct pdesc {
  41         void *addr;
  42         void *gp;
  43 };
  44
  45 static struct ia64_sal_systab *esi_systab;
  46
  47 extern unsigned long esi_phys;
  48
  49 static int __init esi_init (void)
  50 {
  51         struct ia64_sal_systab *systab;
  52         char *p;
  53         int i;
  54
  55         if (esi_phys == EFI_INVALID_TABLE_ADDR)
  56                 return -ENODEV;
  57
  58         systab = __va(esi_phys);
  59
  60         if (strncmp(systab->signature, "ESIT", 4) != 0) {
  61                 printk(KERN_ERR "bad signature in ESI system table!");
  62                 return -ENODEV;
  63         }
  64
  65         p = (char *) (systab + 1);
  66         for (i = 0; i < systab->entry_count; i++) {
  67                 /*
  68                  * The first byte of each entry type contains the type
  69                  * descriptor.
  70                  */
  71                 switch (*p) {
  72                       case ESI_DESC_ENTRY_POINT:
  73                         break;
  74                       default:
  75                         printk(KERN_WARNING "Unknown table type %d found in "
  76                                "ESI table, ignoring rest of table\n", *p);
  77                         return -ENODEV;
  78                 }
  79
  80                 p += ESI_DESC_SIZE(*p);
  81         }
  82
  83         esi_systab = systab;
  84         return 0;
  85 }
  86
  87
  88 int ia64_esi_call (efi_guid_t guid, struct ia64_sal_retval *isrvp,
  89                    enum esi_proc_type proc_type, u64 func,
  90                    u64 arg1, u64 arg2, u64 arg3, u64 arg4, u64 arg5, u64 arg6,
  91                    u64 arg7)
  92 {
  93         struct ia64_fpreg fr[6];
  94         unsigned long flags = 0;
  95         int i;
  96         char *p;
  97
  98         if (!esi_systab)
  99                 return -1;
 100
 101         p = (char *) (esi_systab + 1);
 102         for (i = 0; i < esi_systab->entry_count; i++) {
 103                 if (*p == ESI_DESC_ENTRY_POINT) {
 104                         ia64_esi_desc_entry_point_t *esi = (void *)p;
 105                         if (!efi_guidcmp(guid, esi->guid)) {
 106                                 ia64_sal_handler esi_proc;
 107                                 struct pdesc pdesc;
 108
 109                                 pdesc.addr = __va(esi->esi_proc);
 110                                 pdesc.gp = __va(esi->gp);
 111
 112                                 esi_proc = (ia64_sal_handler) &pdesc;
 113
 114                                 ia64_save_scratch_fpregs(fr);
 115                                 if (proc_type == ESI_PROC_SERIALIZED)
 116                                         spin_lock_irqsave(&sal_lock, flags);
 117                                 else if (proc_type == ESI_PROC_MP_SAFE)
 118                                         local_irq_save(flags);
 119                                 else
 120                                         preempt_disable();
 121                                 *isrvp = (*esi_proc)(func, arg1, arg2, arg3,
 122                                                      arg4, arg5, arg6, arg7);
 123                                 if (proc_type == ESI_PROC_SERIALIZED)
 124                                         spin_unlock_irqrestore(&sal_lock,
 125                                                                flags);
 126                                 else if (proc_type == ESI_PROC_MP_SAFE)
 127                                         local_irq_restore(flags);
 128                                 else
 129                                         preempt_enable();
 130                                 ia64_load_scratch_fpregs(fr);
 131                                 return 0;
 132                         }
 133                 }
 134                 p += ESI_DESC_SIZE(*p);
 135         }
 136         return -1;
 137 }
 138 EXPORT_SYMBOL_GPL(ia64_esi_call);
 139
 140 int ia64_esi_call_phys (efi_guid_t guid, struct ia64_sal_retval *isrvp,
 141                         u64 func, u64 arg1, u64 arg2, u64 arg3, u64 arg4,
 142                         u64 arg5, u64 arg6, u64 arg7)
 143 {
 144         struct ia64_fpreg fr[6];
 145         unsigned long flags;
 146         u64 esi_params[8];
 147         char *p;
 148         int i;
 149
 150         if (!esi_systab)
 151                 return -1;
 152
 153         p = (char *) (esi_systab + 1);
 154         for (i = 0; i < esi_systab->entry_count; i++) {
 155                 if (*p == ESI_DESC_ENTRY_POINT) {
 156                         ia64_esi_desc_entry_point_t *esi = (void *)p;
 157                         if (!efi_guidcmp(guid, esi->guid)) {
 158                                 ia64_sal_handler esi_proc;
 159                                 struct pdesc pdesc;
 160
 161                                 pdesc.addr = (void *)esi->esi_proc;
 162                                 pdesc.gp = (void *)esi->gp;
 163
 164                                 esi_proc = (ia64_sal_handler) &pdesc;
 165
 166                                 esi_params[0] = func;
 167                                 esi_params[1] = arg1;
 168                                 esi_params[2] = arg2;
 169                                 esi_params[3] = arg3;
 170                                 esi_params[4] = arg4;
 171                                 esi_params[5] = arg5;
 172                                 esi_params[6] = arg6;
 173                                 esi_params[7] = arg7;
 174                                 ia64_save_scratch_fpregs(fr);
 175                                 spin_lock_irqsave(&sal_lock, flags);
 176                                 *isrvp = esi_call_phys(esi_proc, esi_params);
 177                                 spin_unlock_irqrestore(&sal_lock, flags);
 178                                 ia64_load_scratch_fpregs(fr);
 179                                 return 0;
 180                         }
 181                 }
 182                 p += ESI_DESC_SIZE(*p);
 183         }
 184         return -1;
 185 }
 186 EXPORT_SYMBOL_GPL(ia64_esi_call_phys);
 187
 188 static void __exit esi_exit (void)
 189 {
 190 }
 191
 192 module_init(esi_init);
 193 module_exit(esi_exit);  /* makes module removable... */