Merge branch 'upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/vitb/linux...
[linux-2.6] / arch / sparc / mm / btfixup.c
1 /* $Id: btfixup.c,v 1.10 2000/05/09 17:40:13 davem Exp $
2  * btfixup.c: Boot time code fixup and relocator, so that
3  * we can get rid of most indirect calls to achieve single
4  * image sun4c and srmmu kernel.
5  *
6  * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
7  */
8
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <asm/btfixup.h>
12 #include <asm/page.h>
13 #include <asm/pgalloc.h>
14 #include <asm/pgtable.h>
15 #include <asm/oplib.h>
16 #include <asm/system.h>
17 #include <asm/cacheflush.h>
18
19 #define BTFIXUP_OPTIMIZE_NOP
20 #define BTFIXUP_OPTIMIZE_OTHER
21
22 extern char *srmmu_name;
23 static char version[] __initdata = "Boot time fixup v1.6. 4/Mar/98 Jakub Jelinek (jj@ultra.linux.cz). Patching kernel for ";
24 #ifdef CONFIG_SUN4
25 static char str_sun4c[] __initdata = "sun4\n";
26 #else
27 static char str_sun4c[] __initdata = "sun4c\n";
28 #endif
29 static char str_srmmu[] __initdata = "srmmu[%s]/";
30 static char str_iommu[] __initdata = "iommu\n";
31 static char str_iounit[] __initdata = "io-unit\n";
32
33 static int visited __initdata = 0;
34 extern unsigned int ___btfixup_start[], ___btfixup_end[], __init_begin[], __init_end[], __init_text_end[];
35 extern unsigned int _stext[], _end[], __start___ksymtab[], __stop___ksymtab[];
36 static char wrong_f[] __initdata = "Trying to set f fixup %p to invalid function %08x\n";
37 static char wrong_b[] __initdata = "Trying to set b fixup %p to invalid function %08x\n";
38 static char wrong_s[] __initdata = "Trying to set s fixup %p to invalid value %08x\n";
39 static char wrong_h[] __initdata = "Trying to set h fixup %p to invalid value %08x\n";
40 static char wrong_a[] __initdata = "Trying to set a fixup %p to invalid value %08x\n";
41 static char wrong[] __initdata = "Wrong address for %c fixup %p\n";
42 static char insn_f[] __initdata = "Fixup f %p refers to weird instructions at %p[%08x,%08x]\n";
43 static char insn_b[] __initdata = "Fixup b %p doesn't refer to a SETHI at %p[%08x]\n";
44 static char insn_s[] __initdata = "Fixup s %p doesn't refer to an OR at %p[%08x]\n";
45 static char insn_h[] __initdata = "Fixup h %p doesn't refer to a SETHI at %p[%08x]\n";
46 static char insn_a[] __initdata = "Fixup a %p doesn't refer to a SETHI nor OR at %p[%08x]\n";
47 static char insn_i[] __initdata = "Fixup i %p doesn't refer to a valid instruction at %p[%08x]\n";
48 static char fca_und[] __initdata = "flush_cache_all undefined in btfixup()\n";
49 static char wrong_setaddr[] __initdata = "Garbled CALL/INT patch at %p[%08x,%08x,%08x]=%08x\n";
50
51 #ifdef BTFIXUP_OPTIMIZE_OTHER
52 static void __init set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
53 {
54         if (!fmangled)
55                 *addr = value;
56         else {
57                 unsigned int *q = (unsigned int *)q1;
58                 if (*addr == 0x01000000) {
59                         /* Noped */
60                         *q = value;
61                 } else if (addr[-1] == *q) {
62                         /* Moved */
63                         addr[-1] = value;
64                         *q = value;
65                 } else {
66                         prom_printf(wrong_setaddr, addr-1, addr[-1], *addr, *q, value);
67                         prom_halt();
68                 }
69         }
70 }
71 #else
72 static __inline__ void set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
73 {
74         *addr = value;
75 }
76 #endif
77
78 void __init btfixup(void)
79 {
80         unsigned int *p, *q;
81         int type, count;
82         unsigned insn;
83         unsigned *addr;
84         int fmangled = 0;
85         void (*flush_cacheall)(void);
86         
87         if (!visited) {
88                 visited++;
89                 printk(version);
90                 if (ARCH_SUN4C_SUN4)
91                         printk(str_sun4c);
92                 else {
93                         printk(str_srmmu, srmmu_name);
94                         if (sparc_cpu_model == sun4d)
95                                 printk(str_iounit);
96                         else
97                                 printk(str_iommu);
98                 }
99         }
100         for (p = ___btfixup_start; p < ___btfixup_end; ) {
101                 count = p[2];
102                 q = p + 3;
103                 switch (type = *(unsigned char *)p) {
104                 case 'f': 
105                         count = p[3];
106                         q = p + 4;
107                         if (((p[0] & 1) || p[1]) 
108                             && ((p[1] & 3) || (unsigned *)(p[1]) < _stext || (unsigned *)(p[1]) >= _end)) {
109                                 prom_printf(wrong_f, p, p[1]);
110                                 prom_halt();
111                         }
112                         break;
113                 case 'b':
114                         if (p[1] < (unsigned long)__init_begin || p[1] >= (unsigned long)__init_text_end || (p[1] & 3)) {
115                                 prom_printf(wrong_b, p, p[1]);
116                                 prom_halt();
117                         }
118                         break;
119                 case 's':
120                         if (p[1] + 0x1000 >= 0x2000) {
121                                 prom_printf(wrong_s, p, p[1]);
122                                 prom_halt();
123                         }
124                         break;
125                 case 'h':
126                         if (p[1] & 0x3ff) {
127                                 prom_printf(wrong_h, p, p[1]);
128                                 prom_halt();
129                         }
130                         break;
131                 case 'a':
132                         if (p[1] + 0x1000 >= 0x2000 && (p[1] & 0x3ff)) {
133                                 prom_printf(wrong_a, p, p[1]);
134                                 prom_halt();
135                         }
136                         break;
137                 }
138                 if (p[0] & 1) {
139                         p[0] &= ~1;
140                         while (count) {
141                                 fmangled = 0;
142                                 addr = (unsigned *)*q;
143                                 if (addr < _stext || addr >= _end) {
144                                         prom_printf(wrong, type, p);
145                                         prom_halt();
146                                 }
147                                 insn = *addr;
148 #ifdef BTFIXUP_OPTIMIZE_OTHER                           
149                                 if (type != 'f' && q[1]) {
150                                         insn = *(unsigned int *)q[1];
151                                         if (!insn || insn == 1)
152                                                 insn = *addr;
153                                         else
154                                                 fmangled = 1;
155                                 }
156 #endif
157                                 switch (type) {
158                                 case 'f':       /* CALL */
159                                         if (addr >= __start___ksymtab && addr < __stop___ksymtab) {
160                                                 *addr = p[1];
161                                                 break;
162                                         } else if (!q[1]) {
163                                                 if ((insn & 0xc1c00000) == 0x01000000) { /* SETHI */
164                                                         *addr = (insn & 0xffc00000) | (p[1] >> 10); break;
165                                                 } else if ((insn & 0xc1f82000) == 0x80102000) { /* OR X, %LO(i), Y */
166                                                         *addr = (insn & 0xffffe000) | (p[1] & 0x3ff); break;
167                                                 } else if ((insn & 0xc0000000) != 0x40000000) { /* !CALL */
168                                 bad_f:
169                                                         prom_printf(insn_f, p, addr, insn, addr[1]);
170                                                         prom_halt();
171                                                 }
172                                         } else if (q[1] != 1)
173                                                 addr[1] = q[1];
174                                         if (p[2] == BTFIXUPCALL_NORM) {
175                                 norm_f: 
176                                                 *addr = 0x40000000 | ((p[1] - (unsigned)addr) >> 2);
177                                                 q[1] = 0;
178                                                 break;
179                                         }
180 #ifndef BTFIXUP_OPTIMIZE_NOP
181                                         goto norm_f;
182 #else
183                                         if (!(addr[1] & 0x80000000)) {
184                                                 if ((addr[1] & 0xc1c00000) != 0x01000000)       /* !SETHI */
185                                                         goto bad_f; /* CALL, Bicc, FBfcc, CBccc are weird in delay slot, aren't they? */
186                                         } else {
187                                                 if ((addr[1] & 0x01800000) == 0x01800000) {
188                                                         if ((addr[1] & 0x01f80000) == 0x01e80000) {
189                                                                 /* RESTORE */
190                                                                 goto norm_f; /* It is dangerous to patch that */
191                                                         }
192                                                         goto bad_f;
193                                                 }
194                                                 if ((addr[1] & 0xffffe003) == 0x9e03e000) {
195                                                         /* ADD %O7, XX, %o7 */
196                                                         int displac = (addr[1] << 19);
197                                                         
198                                                         displac = (displac >> 21) + 2;
199                                                         *addr = (0x10800000) + (displac & 0x3fffff);
200                                                         q[1] = addr[1];
201                                                         addr[1] = p[2];
202                                                         break;
203                                                 }
204                                                 if ((addr[1] & 0x201f) == 0x200f || (addr[1] & 0x7c000) == 0x3c000)
205                                                         goto norm_f; /* Someone is playing bad tricks with us: rs1 or rs2 is o7 */
206                                                 if ((addr[1] & 0x3e000000) == 0x1e000000)
207                                                         goto norm_f; /* rd is %o7. We'd better take care. */
208                                         }
209                                         if (p[2] == BTFIXUPCALL_NOP) {
210                                                 *addr = 0x01000000;
211                                                 q[1] = 1;
212                                                 break;
213                                         }
214 #ifndef BTFIXUP_OPTIMIZE_OTHER
215                                         goto norm_f;
216 #else
217                                         if (addr[1] == 0x01000000) {    /* NOP in the delay slot */
218                                                 q[1] = addr[1];
219                                                 *addr = p[2];
220                                                 break;
221                                         }
222                                         if ((addr[1] & 0xc0000000) != 0xc0000000) {
223                                                 /* Not a memory operation */
224                                                 if ((addr[1] & 0x30000000) == 0x10000000) {
225                                                         /* Ok, non-memory op with rd %oX */
226                                                         if ((addr[1] & 0x3e000000) == 0x1c000000)
227                                                                 goto bad_f; /* Aiee. Someone is playing strange %sp tricks */
228                                                         if ((addr[1] & 0x3e000000) > 0x12000000 ||
229                                                             ((addr[1] & 0x3e000000) == 0x12000000 &&
230                                                              p[2] != BTFIXUPCALL_STO1O0 && p[2] != BTFIXUPCALL_SWAPO0O1) ||
231                                                             ((p[2] & 0xffffe000) == BTFIXUPCALL_RETINT(0))) {
232                                                                 /* Nobody uses the result. We can nop it out. */
233                                                                 *addr = p[2];
234                                                                 q[1] = addr[1];
235                                                                 addr[1] = 0x01000000;
236                                                                 break;
237                                                         }
238                                                         if ((addr[1] & 0xf1ffffe0) == 0x90100000) {
239                                                                 /* MOV %reg, %Ox */
240                                                                 if ((addr[1] & 0x3e000000) == 0x10000000 &&
241                                                                     (p[2] & 0x7c000) == 0x20000) {
242                                                                         /* Ok, it is call xx; mov reg, %o0 and call optimizes
243                                                                            to doing something on %o0. Patch the patch. */
244                                                                         *addr = (p[2] & ~0x7c000) | ((addr[1] & 0x1f) << 14);
245                                                                         q[1] = addr[1];
246                                                                         addr[1] = 0x01000000;
247                                                                         break;
248                                                                 }
249                                                                 if ((addr[1] & 0x3e000000) == 0x12000000 &&
250                                                                     p[2] == BTFIXUPCALL_STO1O0) {
251                                                                         *addr = (p[2] & ~0x3e000000) | ((addr[1] & 0x1f) << 25);
252                                                                         q[1] = addr[1];
253                                                                         addr[1] = 0x01000000;
254                                                                         break;
255                                                                 }
256                                                         }
257                                                 }
258                                         }
259                                         *addr = addr[1];
260                                         q[1] = addr[1];
261                                         addr[1] = p[2];
262                                         break;
263 #endif /* BTFIXUP_OPTIMIZE_OTHER */
264 #endif /* BTFIXUP_OPTIMIZE_NOP */
265                                 case 'b':       /* BLACKBOX */
266                                         /* Has to be sethi i, xx */
267                                         if ((insn & 0xc1c00000) != 0x01000000) {
268                                                 prom_printf(insn_b, p, addr, insn);
269                                                 prom_halt();
270                                         } else {
271                                                 void (*do_fixup)(unsigned *);
272                                                 
273                                                 do_fixup = (void (*)(unsigned *))p[1];
274                                                 do_fixup(addr);
275                                         }
276                                         break;
277                                 case 's':       /* SIMM13 */
278                                         /* Has to be or %g0, i, xx */
279                                         if ((insn & 0xc1ffe000) != 0x80102000) {
280                                                 prom_printf(insn_s, p, addr, insn);
281                                                 prom_halt();
282                                         }
283                                         set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x1fff));
284                                         break;
285                                 case 'h':       /* SETHI */
286                                         /* Has to be sethi i, xx */
287                                         if ((insn & 0xc1c00000) != 0x01000000) {
288                                                 prom_printf(insn_h, p, addr, insn);
289                                                 prom_halt();
290                                         }
291                                         set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
292                                         break;
293                                 case 'a':       /* HALF */
294                                         /* Has to be sethi i, xx or or %g0, i, xx */
295                                         if ((insn & 0xc1c00000) != 0x01000000 &&
296                                             (insn & 0xc1ffe000) != 0x80102000) {
297                                                 prom_printf(insn_a, p, addr, insn);
298                                                 prom_halt();
299                                         }
300                                         if (p[1] & 0x3ff)
301                                                 set_addr(addr, q[1], fmangled, 
302                                                         (insn & 0x3e000000) | 0x80102000 | (p[1] & 0x1fff));
303                                         else
304                                                 set_addr(addr, q[1], fmangled, 
305                                                         (insn & 0x3e000000) | 0x01000000 | (p[1] >> 10));
306                                         break;
307                                 case 'i':       /* INT */
308                                         if ((insn & 0xc1c00000) == 0x01000000) /* %HI */
309                                                 set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
310                                         else if ((insn & 0x80002000) == 0x80002000 &&
311                                                  (insn & 0x01800000) != 0x01800000) /* %LO */
312                                                 set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x3ff));
313                                         else {
314                                                 prom_printf(insn_i, p, addr, insn);
315                                                 prom_halt();
316                                         }
317                                         break;
318                                 }
319                                 count -= 2;
320                                 q += 2;
321                         }
322                 } else
323                         p = q + count;
324         }
325 #ifdef CONFIG_SMP
326         flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(local_flush_cache_all);
327 #else
328         flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(flush_cache_all);
329 #endif
330         if (!flush_cacheall) {
331                 prom_printf(fca_und);
332                 prom_halt();
333         }
334         (*flush_cacheall)();
335 }