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
set_addr(unsigned int * addr,unsigned int q1,int fmangled,unsigned int value)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
set_addr(unsigned int * addr,unsigned int q1,int fmangled,unsigned int value)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
btfixup(void)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 &&
306 (insn & 0x01800000) != 0x01800000) /* %LO */
307 set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x3ff));
308 else {
309 prom_printf(insn_i, p, addr, insn);
310 prom_halt();
311 }
312 break;
313 }
314 count -= 2;
315 q += 2;
316 }
317 } else
318 p = q + count;
319 }
320 #ifdef CONFIG_SMP
321 flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(local_flush_cache_all);
322 #else
323 flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(flush_cache_all);
324 #endif
325 if (!flush_cacheall) {
326 prom_printf(fca_und);
327 prom_halt();
328 }
329 (*flush_cacheall)();
330 }
331