aboutsummaryrefslogtreecommitdiffstats
path: root/arch/sparc/mm/btfixup.c
blob: 5175ac2f4820c603d55e5fba0c06b735080edf96 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
/* btfixup.c: Boot time code fixup and relocator, so that
 * we can get rid of most indirect calls to achieve single
 * image sun4c and srmmu kernel.
 *
 * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/btfixup.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/oplib.h>
#include <asm/system.h>
#include <asm/cacheflush.h>

#define BTFIXUP_OPTIMIZE_NOP
#define BTFIXUP_OPTIMIZE_OTHER

extern char *srmmu_name;
static char version[] __initdata = "Boot time fixup v1.6. 4/Mar/98 Jakub Jelinek (jj@ultra.linux.cz). Patching kernel for ";
static char str_sun4c[] __initdata = "sun4c\n";
static char str_srmmu[] __initdata = "srmmu[%s]/";
static char str_iommu[] __initdata = "iommu\n";
static char str_iounit[] __initdata = "io-unit\n";

static int visited __initdata = 0;
extern unsigned int ___btfixup_start[], ___btfixup_end[], __init_begin[], __init_end[], __init_text_end[];
extern unsigned int _stext[], _end[], __start___ksymtab[], __stop___ksymtab[];
static char wrong_f[] __initdata = "Trying to set f fixup %p to invalid function %08x\n";
static char wrong_b[] __initdata = "Trying to set b fixup %p to invalid function %08x\n";
static char wrong_s[] __initdata = "Trying to set s fixup %p to invalid value %08x\n";
static char wrong_h[] __initdata = "Trying to set h fixup %p to invalid value %08x\n";
static char wrong_a[] __initdata = "Trying to set a fixup %p to invalid value %08x\n";
static char wrong[] __initdata = "Wrong address for %c fixup %p\n";
static char insn_f[] __initdata = "Fixup f %p refers to weird instructions at %p[%08x,%08x]\n";
static char insn_b[] __initdata = "Fixup b %p doesn't refer to a SETHI at %p[%08x]\n";
static char insn_s[] __initdata = "Fixup s %p doesn't refer to an OR at %p[%08x]\n";
static char insn_h[] __initdata = "Fixup h %p doesn't refer to a SETHI at %p[%08x]\n";
static char insn_a[] __initdata = "Fixup a %p doesn't refer to a SETHI nor OR at %p[%08x]\n";
static char insn_i[] __initdata = "Fixup i %p doesn't refer to a valid instruction at %p[%08x]\n";
static char fca_und[] __initdata = "flush_cache_all undefined in btfixup()\n";
static char wrong_setaddr[] __initdata = "Garbled CALL/INT patch at %p[%08x,%08x,%08x]=%08x\n";

#ifdef BTFIXUP_OPTIMIZE_OTHER
static void __init set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
{
	if (!fmangled)
		*addr = value;
	else {
		unsigned int *q = (unsigned int *)q1;
		if (*addr == 0x01000000) {
			/* Noped */
			*q = value;
		} else if (addr[-1] == *q) {
			/* Moved */
			addr[-1] = value;
			*q = value;
		} else {
			prom_printf(wrong_setaddr, addr-1, addr[-1], *addr, *q, value);
			prom_halt();
		}
	}
}
#else
static inline void set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value)
{
	*addr = value;
}
#endif

void __init btfixup(void)
{
	unsigned int *p, *q;
	int type, count;
	unsigned insn;
	unsigned *addr;
	int fmangled = 0;
	void (*flush_cacheall)(void);
	
	if (!visited) {
		visited++;
		printk(version);
		if (ARCH_SUN4C)
			printk(str_sun4c);
		else {
			printk(str_srmmu, srmmu_name);
			if (sparc_cpu_model == sun4d)
				printk(str_iounit);
			else
				printk(str_iommu);
		}
	}
	for (p = ___btfixup_start; p < ___btfixup_end; ) {
		count = p[2];
		q = p + 3;
		switch (type = *(unsigned char *)p) {
		case 'f': 
			count = p[3];
			q = p + 4;
			if (((p[0] & 1) || p[1]) 
			    && ((p[1] & 3) || (unsigned *)(p[1]) < _stext || (unsigned *)(p[1]) >= _end)) {
				prom_printf(wrong_f, p, p[1]);
				prom_halt();
			}
			break;
		case 'b':
			if (p[1] < (unsigned long)__init_begin || p[1] >= (unsigned long)__init_text_end || (p[1] & 3)) {
				prom_printf(wrong_b, p, p[1]);
				prom_halt();
			}
			break;
		case 's':
			if (p[1] + 0x1000 >= 0x2000) {
				prom_printf(wrong_s, p, p[1]);
				prom_halt();
			}
			break;
		case 'h':
			if (p[1] & 0x3ff) {
				prom_printf(wrong_h, p, p[1]);
				prom_halt();
			}
			break;
		case 'a':
			if (p[1] + 0x1000 >= 0x2000 && (p[1] & 0x3ff)) {
				prom_printf(wrong_a, p, p[1]);
				prom_halt();
			}
			break;
		}
		if (p[0] & 1) {
			p[0] &= ~1;
			while (count) {
				fmangled = 0;
				addr = (unsigned *)*q;
				if (addr < _stext || addr >= _end) {
					prom_printf(wrong, type, p);
					prom_halt();
				}
				insn = *addr;
#ifdef BTFIXUP_OPTIMIZE_OTHER				
				if (type != 'f' && q[1]) {
					insn = *(unsigned int *)q[1];
					if (!insn || insn == 1)
						insn = *addr;
					else
						fmangled = 1;
				}
#endif
				switch (type) {
				case 'f':	/* CALL */
					if (addr >= __start___ksymtab && addr < __stop___ksymtab) {
						*addr = p[1];
						break;
					} else if (!q[1]) {
						if ((insn & 0xc1c00000) == 0x01000000) { /* SETHI */
							*addr = (insn & 0xffc00000) | (p[1] >> 10); break;
						} else if ((insn & 0xc1f82000) == 0x80102000) { /* OR X, %LO(i), Y */
							*addr = (insn & 0xffffe000) | (p[1] & 0x3ff); break;
						} else if ((insn & 0xc0000000) != 0x40000000) { /* !CALL */
				bad_f:
							prom_printf(insn_f, p, addr, insn, addr[1]);
							prom_halt();
						}
					} else if (q[1] != 1)
						addr[1] = q[1];
					if (p[2] == BTFIXUPCALL_NORM) {
				norm_f:	
						*addr = 0x40000000 | ((p[1] - (unsigned)addr) >> 2);
						q[1] = 0;
						break;
					}
#ifndef BTFIXUP_OPTIMIZE_NOP
					goto norm_f;
#else
					if (!(addr[1] & 0x80000000)) {
						if ((addr[1] & 0xc1c00000) != 0x01000000)	/* !SETHI */
							goto bad_f; /* CALL, Bicc, FBfcc, CBccc are weird in delay slot, aren't they? */
					} else {
						if ((addr[1] & 0x01800000) == 0x01800000) {
							if ((addr[1] & 0x01f80000) == 0x01e80000) {
								/* RESTORE */
								goto norm_f; /* It is dangerous to patch that */
							}
							goto bad_f;
						}
						if ((addr[1] & 0xffffe003) == 0x9e03e000) {
							/* ADD %O7, XX, %o7 */
							int displac = (addr[1] << 19);
							
							displac = (displac >> 21) + 2;
							*addr = (0x10800000) + (displac & 0x3fffff);
							q[1] = addr[1];
							addr[1] = p[2];
							break;
						}
						if ((addr[1] & 0x201f) == 0x200f || (addr[1] & 0x7c000) == 0x3c000)
							goto norm_f; /* Someone is playing bad tricks with us: rs1 or rs2 is o7 */
						if ((addr[1] & 0x3e000000) == 0x1e000000)
							goto norm_f; /* rd is %o7. We'd better take care. */
					}
					if (p[2] == BTFIXUPCALL_NOP) {
						*addr = 0x01000000;
						q[1] = 1;
						break;
					}
#ifndef BTFIXUP_OPTIMIZE_OTHER
					goto norm_f;
#else
					if (addr[1] == 0x01000000) {	/* NOP in the delay slot */
						q[1] = addr[1];
						*addr = p[2];
						break;
					}
					if ((addr[1] & 0xc0000000) != 0xc0000000) {
						/* Not a memory operation */
						if ((addr[1] & 0x30000000) == 0x10000000) {
							/* Ok, non-memory op with rd %oX */
							if ((addr[1] & 0x3e000000) == 0x1c000000)
								goto bad_f; /* Aiee. Someone is playing strange %sp tricks */
							if ((addr[1] & 0x3e000000) > 0x12000000 ||
							    ((addr[1] & 0x3e000000) == 0x12000000 &&
							     p[2] != BTFIXUPCALL_STO1O0 && p[2] != BTFIXUPCALL_SWAPO0O1) ||
							    ((p[2] & 0xffffe000) == BTFIXUPCALL_RETINT(0))) {
								/* Nobody uses the result. We can nop it out. */
								*addr = p[2];
								q[1] = addr[1];
								addr[1] = 0x01000000;
								break;
							}
							if ((addr[1] & 0xf1ffffe0) == 0x90100000) {
								/* MOV %reg, %Ox */
								if ((addr[1] & 0x3e000000) == 0x10000000 &&
								    (p[2] & 0x7c000) == 0x20000) {
								    	/* Ok, it is call xx; mov reg, %o0 and call optimizes
								    	   to doing something on %o0. Patch the patch. */
									*addr = (p[2] & ~0x7c000) | ((addr[1] & 0x1f) << 14);
									q[1] = addr[1];
									addr[1] = 0x01000000;
									break;
								}
								if ((addr[1] & 0x3e000000) == 0x12000000 &&
								    p[2] == BTFIXUPCALL_STO1O0) {
								    	*addr = (p[2] & ~0x3e000000) | ((addr[1] & 0x1f) << 25);
								    	q[1] = addr[1];
								    	addr[1] = 0x01000000;
								    	break;
								}
							}
						}
					}
					*addr = addr[1];
					q[1] = addr[1];
					addr[1] = p[2];
					break;
#endif /* BTFIXUP_OPTIMIZE_OTHER */
#endif /* BTFIXUP_OPTIMIZE_NOP */
				case 'b':	/* BLACKBOX */
					/* Has to be sethi i, xx */
					if ((insn & 0xc1c00000) != 0x01000000) {
						prom_printf(insn_b, p, addr, insn);
						prom_halt();
					} else {
						void (*do_fixup)(unsigned *);
						
						do_fixup = (void (*)(unsigned *))p[1];
						do_fixup(addr);
					}
					break;
				case 's':	/* SIMM13 */
					/* Has to be or %g0, i, xx */
					if ((insn & 0xc1ffe000) != 0x80102000) {
						prom_printf(insn_s, p, addr, insn);
						prom_halt();
					}
					set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x1fff));
					break;
				case 'h':	/* SETHI */
					/* Has to be sethi i, xx */
					if ((insn & 0xc1c00000) != 0x01000000) {
						prom_printf(insn_h, p, addr, insn);
						prom_halt();
					}
					set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
					break;
				case 'a':	/* HALF */
					/* Has to be sethi i, xx or or %g0, i, xx */
					if ((insn & 0xc1c00000) != 0x01000000 &&
					    (insn & 0xc1ffe000) != 0x80102000) {
						prom_printf(insn_a, p, addr, insn);
						prom_halt();
					}
					if (p[1] & 0x3ff)
						set_addr(addr, q[1], fmangled, 
							(insn & 0x3e000000) | 0x80102000 | (p[1] & 0x1fff));
					else
						set_addr(addr, q[1], fmangled, 
							(insn & 0x3e000000) | 0x01000000 | (p[1] >> 10));
					break;
				case 'i':	/* INT */
					if ((insn & 0xc1c00000) == 0x01000000) /* %HI */
						set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10));
					else if ((insn & 0x80002000) == 0x80002000 &&
					         (insn & 0x01800000) != 0x01800000) /* %LO */
						set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x3ff));
					else {
						prom_printf(insn_i, p, addr, insn);
						prom_halt();
					}
					break;
				}
				count -= 2;
				q += 2;
			}
		} else
			p = q + count;
	}
#ifdef CONFIG_SMP
	flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(local_flush_cache_all);
#else
	flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(flush_cache_all);
#endif
	if (!flush_cacheall) {
		prom_printf(fca_und);
		prom_halt();
	}
	(*flush_cacheall)();
}