arch/sparc/mm/btfixup.c

   1 /* btfixup.c: Boot time code fixup and relocator, so that
   2  * we can get rid of most indirect calls to achieve single
   3  * image sun4c and srmmu kernel.
   4  *
   5  * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <asm/btfixup.h>
  11 #include <asm/page.h>
  12 #include <asm/pgalloc.h>
  13 #include <asm/pgtable.h>
  14 #include <asm/oplib.h>
  15 #include <asm/cacheflush.h>
  16
  17 #define BTFIXUP_OPTIMIZE_NOP
  18 #define BTFIXUP_OPTIMIZE_OTHER
  19
  20 extern char *srmmu_name;
  21 static char version[] __initdata = "Boot time fixup v1.6. 4/Mar/98 Jakub Jelinek (jj@ultra.linux.cz). Patching kernel for ";
  22 static char str_srmmu[] __initdata = "srmmu[%s]/";
  23 static char str_iommu[] __initdata = "iommu\n";
  24 static char str_iounit[] __initdata = "io-unit\n";
  25
  26 static int visited __initdata = 0;
  27 extern unsigned int ___btfixup_start[], ___btfixup_end[], __init_begin[], __init_end[], __init_text_end[];
  28 extern unsigned int _stext[], _end[], __start___ksymtab[], __stop___ksymtab[];
  29 static char wrong_f[] __initdata = "Trying to set f fixup %p to invalid function %08x\n";
  30 static char wrong_b[] __initdata = "Trying to set b fixup %p to invalid function %08x\n";
  31 static char wrong_s[] __initdata = "Trying to set s fixup %p to invalid value %08x\n";
  32 static char wrong_h[] __initdata = "Trying to set h fixup %p to invalid value %08x\n";
  33 static char wrong_a[] __initdata = "Trying to set a fixup %p to invalid value %08x\n";
  34 static char wrong[] __initdata = "Wrong address for %c fixup %p\n";
  35 static char insn_f[] __initdata = "Fixup f %p refers to weird instructions at %p[%08x,%08x]\n";
  36 static char insn_b[] __initdata = "Fixup b %p doesn't refer to a SETHI at %p[%08x]\n";
  37 static char insn_s[] __initdata = "Fixup s %p doesn't refer to an OR at %p[%08x]\n";
  38 static char insn_h[] __initdata = "Fixup h %p doesn't refer to a SETHI at %p[%08x]\n";
  39 static char insn_a[] __initdata = "Fixup a %p doesn't refer to a SETHI nor OR at %p[%08x]\n";
  40 static char insn_i[] __initdata = "Fixup i %p doesn't refer to a valid instruction at %p[%08x]\n";
  41 static char wrong_setaddr[] __initdata = "Garbled CALL/INT patch at %p[%08x,%08x,%08x]=%08x\n";
  42
  43 #ifdef BTFIXUP_OPTIMIZE_OTHER
  44 static void __init set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
  45 {
  46         if (!fmangled)
  47                 *addr = value;
  48         else {
  49                 unsigned int *q = (unsigned int *)q1;
  50                 if (*addr == 0x01000000) {
  51                         /* Noped */
  52                         *q = value;
  53                 } else if (addr[-1] == *q) {
  54                         /* Moved */
  55                         addr[-1] = value;
  56                         *q = value;
  57                 } else {
  58                         prom_printf(wrong_setaddr, addr-1, addr[-1], *addr, *q, value);
  59                         prom_halt();
  60                 }
  61         }
  62 }
  63 #else
  64 static inline void set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
  65 {
  66         *addr = value;
  67 }
  68 #endif
  69
  70 void __init btfixup(void)
  71 {
  72         unsigned int *p, *q;
  73         int type, count;
  74         unsigned insn;
  75         unsigned *addr;
  76         int fmangled = 0;
  77
  78         if (!visited) {
  79                 visited++;
  80                 printk(version);
  81                 printk(str_srmmu, srmmu_name);
  82                 if (sparc_cpu_model == sun4d)
  83                         printk(str_iounit);
  84                 else
  85                         printk(str_iommu);
  86         }
  87         for (p = ___btfixup_start; p < ___btfixup_end; ) {
  88                 count = p[2];
  89                 q = p + 3;
  90                 switch (type = *(unsigned char *)p) {
  91                 case 'f':
  92                         count = p[3];
  93                         q = p + 4;
  94                         if (((p[0] & 1) || p[1])
  95                             && ((p[1] & 3) || (unsigned *)(p[1]) < _stext || (unsigned *)(p[1]) >= _end)) {
  96                                 prom_printf(wrong_f, p, p[1]);
  97                                 prom_halt();
  98                         }
  99                         break;
 100                 case 'b':
 101                         if (p[1] < (unsigned long)__init_begin || p[1] >= (unsigned long)__init_text_end || (p[1] & 3)) {
 102                                 prom_printf(wrong_b, p, p[1]);
 103                                 prom_halt();
 104                         }
 105                         break;
 106                 case 's':
 107                         if (p[1] + 0x1000 >= 0x2000) {
 108                                 prom_printf(wrong_s, p, p[1]);
 109                                 prom_halt();
 110                         }
 111                         break;
 112                 case 'h':
 113                         if (p[1] & 0x3ff) {
 114                                 prom_printf(wrong_h, p, p[1]);
 115                                 prom_halt();
 116                         }
 117                         break;
 118                 case 'a':
 119                         if (p[1] + 0x1000 >= 0x2000 && (p[1] & 0x3ff)) {
 120                                 prom_printf(wrong_a, p, p[1]);
 121                                 prom_halt();
 122                         }
 123                         break;
 124                 }
 125                 if (p[0] & 1) {
 126                         p[0] &= ~1;
 127                         while (count) {
 128                                 fmangled = 0;
 129                                 addr = (unsigned *)*q;
 130                                 if (addr < _stext || addr >= _end) {
 131                                         prom_printf(wrong, type, p);
 132                                         prom_halt();
 133                                 }
 134                                 insn = *addr;
 135 #ifdef BTFIXUP_OPTIMIZE_OTHER
 136                                 if (type != 'f' && q[1]) {
 137                                         insn = *(unsigned int *)q[1];
 138                                         if (!insn || insn == 1)
 139                                                 insn = *addr;
 140                                         else
 141                                                 fmangled = 1;
 142                                 }
 143 #endif
 144                                 switch (type) {
 145                                 case 'f':       /* CALL */
 146                                         if (addr >= __start___ksymtab && addr < __stop___ksymtab) {
 147                                                 *addr = p[1];
 148                                                 break;
 149                                         } else if (!q[1]) {
 150                                                 if ((insn & 0xc1c00000) == 0x01000000) { /* SETHI */
 151                                                         *addr = (insn & 0xffc00000) | (p[1] >> 10); break;
 152                                                 } else if ((insn & 0xc1f82000) == 0x80102000) { /* OR X, %LO(i), Y */
 153                                                         *addr = (insn & 0xffffe000) | (p[1] & 0x3ff); break;
 154                                                 } else if ((insn & 0xc0000000) != 0x40000000) { /* !CALL */
 155                                 bad_f:
 156                                                         prom_printf(insn_f, p, addr, insn, addr[1]);
 157                                                         prom_halt();
 158                                                 }
 159                                         } else if (q[1] != 1)
 160                                                 addr[1] = q[1];
 161                                         if (p[2] == BTFIXUPCALL_NORM) {
 162                                 norm_f:
 163                                                 *addr = 0x40000000 | ((p[1] - (unsigned)addr) >> 2);
 164                                                 q[1] = 0;
 165                                                 break;
 166                                         }
 167 #ifndef BTFIXUP_OPTIMIZE_NOP
 168                                         goto norm_f;
 169 #else
 170                                         if (!(addr[1] & 0x80000000)) {
 171                                                 if ((addr[1] & 0xc1c00000) != 0x01000000)       /* !SETHI */
 172                                                         goto bad_f; /* CALL, Bicc, FBfcc, CBccc are weird in delay slot, aren't they? */
 173                                         } else {
 174                                                 if ((addr[1] & 0x01800000) == 0x01800000) {
 175                                                         if ((addr[1] & 0x01f80000) == 0x01e80000) {
 176                                                                 /* RESTORE */
 177                                                                 goto norm_f; /* It is dangerous to patch that */
 178                                                         }
 179                                                         goto bad_f;
 180                                                 }
 181                                                 if ((addr[1] & 0xffffe003) == 0x9e03e000) {
 182                                                         /* ADD %O7, XX, %o7 */
 183                                                         int displac = (addr[1] << 19);
 184
 185                                                         displac = (displac >> 21) + 2;
 186                                                         *addr = (0x10800000) + (displac & 0x3fffff);
 187                                                         q[1] = addr[1];
 188                                                         addr[1] = p[2];
 189                                                         break;
 190                                                 }
 191                                                 if ((addr[1] & 0x201f) == 0x200f || (addr[1] & 0x7c000) == 0x3c000)
 192                                                         goto norm_f; /* Someone is playing bad tricks with us: rs1 or rs2 is o7 */
 193                                                 if ((addr[1] & 0x3e000000) == 0x1e000000)
 194                                                         goto norm_f; /* rd is %o7. We'd better take care. */
 195                                         }
 196                                         if (p[2] == BTFIXUPCALL_NOP) {
 197                                                 *addr = 0x01000000;
 198                                                 q[1] = 1;
 199                                                 break;
 200                                         }
 201 #ifndef BTFIXUP_OPTIMIZE_OTHER
 202                                         goto norm_f;
 203 #else
 204                                         if (addr[1] == 0x01000000) {    /* NOP in the delay slot */
 205                                                 q[1] = addr[1];
 206                                                 *addr = p[2];
 207                                                 break;
 208                                         }
 209                                         if ((addr[1] & 0xc0000000) != 0xc0000000) {
 210                                                 /* Not a memory operation */
 211                                                 if ((addr[1] & 0x30000000) == 0x10000000) {
 212                                                         /* Ok, non-memory op with rd %oX */
 213                                                         if ((addr[1] & 0x3e000000) == 0x1c000000)
 214                                                                 goto bad_f; /* Aiee. Someone is playing strange %sp tricks */
 215                                                         if ((addr[1] & 0x3e000000) > 0x12000000 ||
 216                                                             ((addr[1] & 0x3e000000) == 0x12000000 &&
 217                                                              p[2] != BTFIXUPCALL_STO1O0 && p[2] != BTFIXUPCALL_SWAPO0O1) ||
 218                                                             ((p[2] & 0xffffe000) == BTFIXUPCALL_RETINT(0))) {
 219                                                                 /* Nobody uses the result. We can nop it out. */
 220                                                                 *addr = p[2];
 221                                                                 q[1] = addr[1];
 222                                                                 addr[1] = 0x01000000;
 223                                                                 break;
 224                                                         }
 225                                                         if ((addr[1] & 0xf1ffffe0) == 0x90100000) {
 226                                                                 /* MOV %reg, %Ox */
 227                                                                 if ((addr[1] & 0x3e000000) == 0x10000000 &&
 228                                                                     (p[2] & 0x7c000) == 0x20000) {
 229                                                                         /* Ok, it is call xx; mov reg, %o0 and call optimizes
 230                                                                            to doing something on %o0. Patch the patch. */
 231                                                                         *addr = (p[2] & ~0x7c000) | ((addr[1] & 0x1f) << 14);
 232                                                                         q[1] = addr[1];
 233                                                                         addr[1] = 0x01000000;
 234                                                                         break;
 235                                                                 }
 236                                                                 if ((addr[1] & 0x3e000000) == 0x12000000 &&
 237                                                                     p[2] == BTFIXUPCALL_STO1O0) {
 238                                                                         *addr = (p[2] & ~0x3e000000) | ((addr[1] & 0x1f) << 25);
 239                                                                         q[1] = addr[1];
 240                                                                         addr[1] = 0x01000000;
 241                                                                         break;
 242                                                                 }
 243                                                         }
 244                                                 }
 245                                         }
 246                                         *addr = addr[1];
 247                                         q[1] = addr[1];
 248                                         addr[1] = p[2];
 249                                         break;
 250 #endif /* BTFIXUP_OPTIMIZE_OTHER */
 251 #endif /* BTFIXUP_OPTIMIZE_NOP */
 252                                 case 'b':       /* BLACKBOX */
 253                                         /* Has to be sethi i, xx */
 254                                         if ((insn & 0xc1c00000) != 0x01000000) {
 255                                                 prom_printf(insn_b, p, addr, insn);
 256                                                 prom_halt();
 257                                         } else {
 258                                                 void (*do_fixup)(unsigned *);
 259
 260                                                 do_fixup = (void (*)(unsigned *))p[1];
 261                                                 do_fixup(addr);
 262                                         }
 263                                         break;
 264                                 case 's':       /* SIMM13 */
 265                                         /* Has to be or %g0, i, xx */
 266                                         if ((insn & 0xc1ffe000) != 0x80102000) {
 267                                                 prom_printf(insn_s, p, addr, insn);
 268                                                 prom_halt();
 269                                         }
 270                                         set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x1fff));
 271                                         break;
 272                                 case 'h':       /* SETHI */
 273                                         /* Has to be sethi i, xx */
 274                                         if ((insn & 0xc1c00000) != 0x01000000) {
 275                                                 prom_printf(insn_h, p, addr, insn);
 276                                                 prom_halt();
 277                                         }
 278                                         set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
 279                                         break;
 280                                 case 'a':       /* HALF */
 281                                         /* Has to be sethi i, xx or or %g0, i, xx */
 282                                         if ((insn & 0xc1c00000) != 0x01000000 &&
 283                                             (insn & 0xc1ffe000) != 0x80102000) {
 284                                                 prom_printf(insn_a, p, addr, insn);
 285                                                 prom_halt();
 286                                         }
 287                                         if (p[1] & 0x3ff)
 288                                                 set_addr(addr, q[1], fmangled,
 289                                                         (insn & 0x3e000000) | 0x80102000 | (p[1] & 0x1fff));
 290                                         else
 291                                                 set_addr(addr, q[1], fmangled,
 292                                                         (insn & 0x3e000000) | 0x01000000 | (p[1] >> 10));
 293                                         break;
 294                                 case 'i':       /* INT */
 295                                         if ((insn & 0xc1c00000) == 0x01000000) /* %HI */
 296                                                 set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
 297                                         else if ((insn & 0x80002000) == 0x80002000) /* %LO */
 298                                                 set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x3ff));
 299                                         else {
 300                                                 prom_printf(insn_i, p, addr, insn);
 301                                                 prom_halt();
 302                                         }
 303                                         break;
 304                                 }
 305                                 count -= 2;
 306                                 q += 2;
 307                         }
 308                 } else
 309                         p = q + count;
 310         }
 311 #ifdef CONFIG_SMP
 312         local_ops->cache_all();
 313 #else
 314         sparc32_cachetlb_ops->cache_all();
 315 #endif
 316 }