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/config.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <asm/btfixup.h>
13 #include <asm/page.h>
14 #include <asm/pgalloc.h>
15 #include <asm/pgtable.h>
16 #include <asm/oplib.h>
17 #include <asm/system.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
set_addr(unsigned int * addr,unsigned int q1,int fmangled,unsigned int value)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
set_addr(unsigned int * addr,unsigned int q1,int fmangled,unsigned int value)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
btfixup(void)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 }
336