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/system.h>
  16 #include <asm/cacheflush.h>
  17
  18 #define BTFIXUP_OPTIMIZE_NOP
  19 #define BTFIXUP_OPTIMIZE_OTHER
  20
  21 extern char *srmmu_name;
  22 static char version[] __initdata = "Boot time fixup v1.6. 4/Mar/98 Jakub Jelinek (jj@ultra.linux.cz). Patching kernel for ";
  23 static char str_sun4c[] __initdata = "sun4c\n";
  24 static char str_srmmu[] __initdata = "srmmu[%s]/";
  25 static char str_iommu[] __initdata = "iommu\n";
  26 static char str_iounit[] __initdata = "io-unit\n";
  27
  28 static int visited __initdata = 0;
  29 extern unsigned int ___btfixup_start[], ___btfixup_end[], __init_begin[], __init_end[], __init_text_end[];
  30 extern unsigned int _stext[], _end[], __start___ksymtab[], __stop___ksymtab[];
  31 static char wrong_f[] __initdata = "Trying to set f fixup %p to invalid function %08x\n";
  32 static char wrong_b[] __initdata = "Trying to set b fixup %p to invalid function %08x\n";
  33 static char wrong_s[] __initdata = "Trying to set s fixup %p to invalid value %08x\n";
  34 static char wrong_h[] __initdata = "Trying to set h fixup %p to invalid value %08x\n";
  35 static char wrong_a[] __initdata = "Trying to set a fixup %p to invalid value %08x\n";
  36 static char wrong[] __initdata = "Wrong address for %c fixup %p\n";
  37 static char insn_f[] __initdata = "Fixup f %p refers to weird instructions at %p[%08x,%08x]\n";
  38 static char insn_b[] __initdata = "Fixup b %p doesn't refer to a SETHI at %p[%08x]\n";
  39 static char insn_s[] __initdata = "Fixup s %p doesn't refer to an OR at %p[%08x]\n";
  40 static char insn_h[] __initdata = "Fixup h %p doesn't refer to a SETHI at %p[%08x]\n";
  41 static char insn_a[] __initdata = "Fixup a %p doesn't refer to a SETHI nor OR at %p[%08x]\n";
  42 static char insn_i[] __initdata = "Fixup i %p doesn't refer to a valid instruction at %p[%08x]\n";
  43 static char fca_und[] __initdata = "flush_cache_all undefined in btfixup()\n";
  44 static char wrong_setaddr[] __initdata = "Garbled CALL/INT patch at %p[%08x,%08x,%08x]=%08x\n";
  45
  46 #ifdef BTFIXUP_OPTIMIZE_OTHER
  47 static void __init set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
  48 {
  49         if (!fmangled)
  50                 *addr = value;
  51         else {
  52                 unsigned int *q = (unsigned int *)q1;
  53                 if (*addr == 0x01000000) {
  54                         /* Noped */
  55                         *q = value;
  56                 } else if (addr[-1] == *q) {
  57                         /* Moved */
  58                         addr[-1] = value;
  59                         *q = value;
  60                 } else {
  61                         prom_printf(wrong_setaddr, addr-1, addr[-1], *addr, *q, value);
  62                         prom_halt();
  63                 }
  64         }
  65 }
  66 #else
  67 static inline void set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
  68 {
  69         *addr = value;
  70 }
  71 #endif
  72
  73 void __init btfixup(void)
  74 {
  75         unsigned int *p, *q;
  76         int type, count;
  77         unsigned insn;
  78         unsigned *addr;
  79         int fmangled = 0;
  80         void (*flush_cacheall)(void);
  81
  82         if (!visited) {
  83                 visited++;
  84                 printk(version);
  85                 if (ARCH_SUN4C)
  86                         printk(str_sun4c);
  87                 else {
  88                         printk(str_srmmu, srmmu_name);
  89                         if (sparc_cpu_model == sun4d)
  90                                 printk(str_iounit);
  91                         else
  92                                 printk(str_iommu);
  93                 }
  94         }
  95         for (p = ___btfixup_start; p < ___btfixup_end; ) {
  96                 count = p[2];
  97                 q = p + 3;
  98                 switch (type = *(unsigned char *)p) {
  99                 case 'f':
 100                         count = p[3];
 101                         q = p + 4;
 102                         if (((p[0] & 1) || p[1])
 103                             && ((p[1] & 3) || (unsigned *)(p[1]) < _stext || (unsigned *)(p[1]) >= _end)) {
 104                                 prom_printf(wrong_f, p, p[1]);
 105                                 prom_halt();
 106                         }
 107                         break;
 108                 case 'b':
 109                         if (p[1] < (unsigned long)__init_begin || p[1] >= (unsigned long)__init_text_end || (p[1] & 3)) {
 110                                 prom_printf(wrong_b, p, p[1]);
 111                                 prom_halt();
 112                         }
 113                         break;
 114                 case 's':
 115                         if (p[1] + 0x1000 >= 0x2000) {
 116                                 prom_printf(wrong_s, p, p[1]);
 117                                 prom_halt();
 118                         }
 119                         break;
 120                 case 'h':
 121                         if (p[1] & 0x3ff) {
 122                                 prom_printf(wrong_h, p, p[1]);
 123                                 prom_halt();
 124                         }
 125                         break;
 126                 case 'a':
 127                         if (p[1] + 0x1000 >= 0x2000 && (p[1] & 0x3ff)) {
 128                                 prom_printf(wrong_a, p, p[1]);
 129                                 prom_halt();
 130                         }
 131                         break;
 132                 }
 133                 if (p[0] & 1) {
 134                         p[0] &= ~1;
 135                         while (count) {
 136                                 fmangled = 0;
 137                                 addr = (unsigned *)*q;
 138                                 if (addr < _stext || addr >= _end) {
 139                                         prom_printf(wrong, type, p);
 140                                         prom_halt();
 141                                 }
 142                                 insn = *addr;
 143 #ifdef BTFIXUP_OPTIMIZE_OTHER
 144                                 if (type != 'f' && q[1]) {
 145                                         insn = *(unsigned int *)q[1];
 146                                         if (!insn || insn == 1)
 147                                                 insn = *addr;
 148                                         else
 149                                                 fmangled = 1;
 150                                 }
 151 #endif
 152                                 switch (type) {
 153                                 case 'f':       /* CALL */
 154                                         if (addr >= __start___ksymtab && addr < __stop___ksymtab) {
 155                                                 *addr = p[1];
 156                                                 break;
 157                                         } else if (!q[1]) {
 158                                                 if ((insn & 0xc1c00000) == 0x01000000) { /* SETHI */
 159                                                         *addr = (insn & 0xffc00000) | (p[1] >> 10); break;
 160                                                 } else if ((insn & 0xc1f82000) == 0x80102000) { /* OR X, %LO(i), Y */
 161                                                         *addr = (insn & 0xffffe000) | (p[1] & 0x3ff); break;
 162                                                 } else if ((insn & 0xc0000000) != 0x40000000) { /* !CALL */
 163                                 bad_f:
 164                                                         prom_printf(insn_f, p, addr, insn, addr[1]);
 165                                                         prom_halt();
 166                                                 }
 167                                         } else if (q[1] != 1)
 168                                                 addr[1] = q[1];
 169                                         if (p[2] == BTFIXUPCALL_NORM) {
 170                                 norm_f:
 171                                                 *addr = 0x40000000 | ((p[1] - (unsigned)addr) >> 2);
 172                                                 q[1] = 0;
 173                                                 break;
 174                                         }
 175 #ifndef BTFIXUP_OPTIMIZE_NOP
 176                                         goto norm_f;
 177 #else
 178                                         if (!(addr[1] & 0x80000000)) {
 179                                                 if ((addr[1] & 0xc1c00000) != 0x01000000)       /* !SETHI */
 180                                                         goto bad_f; /* CALL, Bicc, FBfcc, CBccc are weird in delay slot, aren't they? */
 181                                         } else {
 182                                                 if ((addr[1] & 0x01800000) == 0x01800000) {
 183                                                         if ((addr[1] & 0x01f80000) == 0x01e80000) {
 184                                                                 /* RESTORE */
 185                                                                 goto norm_f; /* It is dangerous to patch that */
 186                                                         }
 187                                                         goto bad_f;
 188                                                 }
 189                                                 if ((addr[1] & 0xffffe003) == 0x9e03e000) {
 190                                                         /* ADD %O7, XX, %o7 */
 191                                                         int displac = (addr[1] << 19);
 192
 193                                                         displac = (displac >> 21) + 2;
 194                                                         *addr = (0x10800000) + (displac & 0x3fffff);
 195                                                         q[1] = addr[1];
 196                                                         addr[1] = p[2];
 197                                                         break;
 198                                                 }
 199                                                 if ((addr[1] & 0x201f) == 0x200f || (addr[1] & 0x7c000) == 0x3c000)
 200                                                         goto norm_f; /* Someone is playing bad tricks with us: rs1 or rs2 is o7 */
 201                                                 if ((addr[1] & 0x3e000000) == 0x1e000000)
 202                                                         goto norm_f; /* rd is %o7. We'd better take care. */
 203                                         }
 204                                         if (p[2] == BTFIXUPCALL_NOP) {
 205                                                 *addr = 0x01000000;
 206                                                 q[1] = 1;
 207                                                 break;
 208                                         }
 209 #ifndef BTFIXUP_OPTIMIZE_OTHER
 210                                         goto norm_f;
 211 #else
 212                                         if (addr[1] == 0x01000000) {    /* NOP in the delay slot */
 213                                                 q[1] = addr[1];
 214                                                 *addr = p[2];
 215                                                 break;
 216                                         }
 217                                         if ((addr[1] & 0xc0000000) != 0xc0000000) {
 218                                                 /* Not a memory operation */
 219                                                 if ((addr[1] & 0x30000000) == 0x10000000) {
 220                                                         /* Ok, non-memory op with rd %oX */
 221                                                         if ((addr[1] & 0x3e000000) == 0x1c000000)
 222                                                                 goto bad_f; /* Aiee. Someone is playing strange %sp tricks */
 223                                                         if ((addr[1] & 0x3e000000) > 0x12000000 ||
 224                                                             ((addr[1] & 0x3e000000) == 0x12000000 &&
 225                                                              p[2] != BTFIXUPCALL_STO1O0 && p[2] != BTFIXUPCALL_SWAPO0O1) ||
 226                                                             ((p[2] & 0xffffe000) == BTFIXUPCALL_RETINT(0))) {
 227                                                                 /* Nobody uses the result. We can nop it out. */
 228                                                                 *addr = p[2];
 229                                                                 q[1] = addr[1];
 230                                                                 addr[1] = 0x01000000;
 231                                                                 break;
 232                                                         }
 233                                                         if ((addr[1] & 0xf1ffffe0) == 0x90100000) {
 234                                                                 /* MOV %reg, %Ox */
 235                                                                 if ((addr[1] & 0x3e000000) == 0x10000000 &&
 236                                                                     (p[2] & 0x7c000) == 0x20000) {
 237                                                                         /* Ok, it is call xx; mov reg, %o0 and call optimizes
 238                                                                            to doing something on %o0. Patch the patch. */
 239                                                                         *addr = (p[2] & ~0x7c000) | ((addr[1] & 0x1f) << 14);
 240                                                                         q[1] = addr[1];
 241                                                                         addr[1] = 0x01000000;
 242                                                                         break;
 243                                                                 }
 244                                                                 if ((addr[1] & 0x3e000000) == 0x12000000 &&
 245                                                                     p[2] == BTFIXUPCALL_STO1O0) {
 246                                                                         *addr = (p[2] & ~0x3e000000) | ((addr[1] & 0x1f) << 25);
 247                                                                         q[1] = addr[1];
 248                                                                         addr[1] = 0x01000000;
 249                                                                         break;
 250                                                                 }
 251                                                         }
 252                                                 }
 253                                         }
 254                                         *addr = addr[1];
 255                                         q[1] = addr[1];
 256                                         addr[1] = p[2];
 257                                         break;
 258 #endif /* BTFIXUP_OPTIMIZE_OTHER */
 259 #endif /* BTFIXUP_OPTIMIZE_NOP */
 260                                 case 'b':       /* BLACKBOX */
 261                                         /* Has to be sethi i, xx */
 262                                         if ((insn & 0xc1c00000) != 0x01000000) {
 263                                                 prom_printf(insn_b, p, addr, insn);
 264                                                 prom_halt();
 265                                         } else {
 266                                                 void (*do_fixup)(unsigned *);
 267
 268                                                 do_fixup = (void (*)(unsigned *))p[1];
 269                                                 do_fixup(addr);
 270                                         }
 271                                         break;
 272                                 case 's':       /* SIMM13 */
 273                                         /* Has to be or %g0, i, xx */
 274                                         if ((insn & 0xc1ffe000) != 0x80102000) {
 275                                                 prom_printf(insn_s, p, addr, insn);
 276                                                 prom_halt();
 277                                         }
 278                                         set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x1fff));
 279                                         break;
 280                                 case 'h':       /* SETHI */
 281                                         /* Has to be sethi i, xx */
 282                                         if ((insn & 0xc1c00000) != 0x01000000) {
 283                                                 prom_printf(insn_h, p, addr, insn);
 284                                                 prom_halt();
 285                                         }
 286                                         set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
 287                                         break;
 288                                 case 'a':       /* HALF */
 289                                         /* Has to be sethi i, xx or or %g0, i, xx */
 290                                         if ((insn & 0xc1c00000) != 0x01000000 &&
 291                                             (insn & 0xc1ffe000) != 0x80102000) {
 292                                                 prom_printf(insn_a, p, addr, insn);
 293                                                 prom_halt();
 294                                         }
 295                                         if (p[1] & 0x3ff)
 296                                                 set_addr(addr, q[1], fmangled,
 297                                                         (insn & 0x3e000000) | 0x80102000 | (p[1] & 0x1fff));
 298                                         else
 299                                                 set_addr(addr, q[1], fmangled,
 300                                                         (insn & 0x3e000000) | 0x01000000 | (p[1] >> 10));
 301                                         break;
 302                                 case 'i':       /* INT */
 303                                         if ((insn & 0xc1c00000) == 0x01000000) /* %HI */
 304                                                 set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
 305                                         else if ((insn & 0x80002000) == 0x80002000) /* %LO */
 306                                                 set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x3ff));
 307                                         else {
 308                                                 prom_printf(insn_i, p, addr, insn);
 309                                                 prom_halt();
 310                                         }
 311                                         break;
 312                                 }
 313                                 count -= 2;
 314                                 q += 2;
 315                         }
 316                 } else
 317                         p = q + count;
 318         }
 319 #ifdef CONFIG_SMP
 320         flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(local_flush_cache_all);
 321 #else
 322         flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(flush_cache_all);
 323 #endif
 324         if (!flush_cacheall) {
 325                 prom_printf(fca_und);
 326                 prom_halt();
 327         }
 328         (*flush_cacheall)();
 329 }