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14cf11af PM |
1 | /* |
2 | * Copyright (c) 1995-1996 Gary Thomas <gdt@linuxppc.org> | |
3 | * Initial PowerPC version. | |
4 | * Copyright (c) 1996 Cort Dougan <cort@cs.nmt.edu> | |
5 | * Rewritten for PReP | |
6 | * Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au> | |
7 | * Low-level exception handers, MMU support, and rewrite. | |
8 | * Copyright (c) 1997 Dan Malek <dmalek@jlc.net> | |
9 | * PowerPC 8xx modifications. | |
10 | * Copyright (c) 1998-1999 TiVo, Inc. | |
11 | * PowerPC 403GCX modifications. | |
12 | * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu> | |
13 | * PowerPC 403GCX/405GP modifications. | |
14 | * Copyright 2000 MontaVista Software Inc. | |
15 | * PPC405 modifications | |
16 | * PowerPC 403GCX/405GP modifications. | |
17 | * Author: MontaVista Software, Inc. | |
18 | * frank_rowand@mvista.com or source@mvista.com | |
19 | * debbie_chu@mvista.com | |
20 | * | |
21 | * | |
22 | * Module name: head_4xx.S | |
23 | * | |
24 | * Description: | |
25 | * Kernel execution entry point code. | |
26 | * | |
27 | * This program is free software; you can redistribute it and/or | |
28 | * modify it under the terms of the GNU General Public License | |
29 | * as published by the Free Software Foundation; either version | |
30 | * 2 of the License, or (at your option) any later version. | |
31 | * | |
32 | */ | |
33 | ||
e7039845 | 34 | #include <linux/init.h> |
14cf11af PM |
35 | #include <asm/processor.h> |
36 | #include <asm/page.h> | |
37 | #include <asm/mmu.h> | |
38 | #include <asm/pgtable.h> | |
14cf11af PM |
39 | #include <asm/cputable.h> |
40 | #include <asm/thread_info.h> | |
41 | #include <asm/ppc_asm.h> | |
42 | #include <asm/asm-offsets.h> | |
46f52210 | 43 | #include <asm/ptrace.h> |
14cf11af PM |
44 | |
45 | /* As with the other PowerPC ports, it is expected that when code | |
46 | * execution begins here, the following registers contain valid, yet | |
47 | * optional, information: | |
48 | * | |
49 | * r3 - Board info structure pointer (DRAM, frequency, MAC address, etc.) | |
50 | * r4 - Starting address of the init RAM disk | |
51 | * r5 - Ending address of the init RAM disk | |
52 | * r6 - Start of kernel command line string (e.g. "mem=96m") | |
53 | * r7 - End of kernel command line string | |
54 | * | |
55 | * This is all going to change RSN when we add bi_recs....... -- Dan | |
56 | */ | |
e7039845 | 57 | __HEAD |
748a7683 KG |
58 | _ENTRY(_stext); |
59 | _ENTRY(_start); | |
14cf11af PM |
60 | |
61 | /* Save parameters we are passed. | |
62 | */ | |
63 | mr r31,r3 | |
64 | mr r30,r4 | |
65 | mr r29,r5 | |
66 | mr r28,r6 | |
67 | mr r27,r7 | |
68 | ||
69 | /* We have to turn on the MMU right away so we get cache modes | |
70 | * set correctly. | |
71 | */ | |
72 | bl initial_mmu | |
73 | ||
74 | /* We now have the lower 16 Meg mapped into TLB entries, and the caches | |
75 | * ready to work. | |
76 | */ | |
77 | turn_on_mmu: | |
78 | lis r0,MSR_KERNEL@h | |
79 | ori r0,r0,MSR_KERNEL@l | |
80 | mtspr SPRN_SRR1,r0 | |
81 | lis r0,start_here@h | |
82 | ori r0,r0,start_here@l | |
83 | mtspr SPRN_SRR0,r0 | |
84 | SYNC | |
85 | rfi /* enables MMU */ | |
86 | b . /* prevent prefetch past rfi */ | |
87 | ||
88 | /* | |
89 | * This area is used for temporarily saving registers during the | |
90 | * critical exception prolog. | |
91 | */ | |
92 | . = 0xc0 | |
93 | crit_save: | |
748a7683 | 94 | _ENTRY(crit_r10) |
14cf11af | 95 | .space 4 |
748a7683 | 96 | _ENTRY(crit_r11) |
14cf11af | 97 | .space 4 |
fca622c5 KG |
98 | _ENTRY(crit_srr0) |
99 | .space 4 | |
100 | _ENTRY(crit_srr1) | |
101 | .space 4 | |
102 | _ENTRY(saved_ksp_limit) | |
103 | .space 4 | |
14cf11af PM |
104 | |
105 | /* | |
106 | * Exception vector entry code. This code runs with address translation | |
ee43eb78 BH |
107 | * turned off (i.e. using physical addresses). We assume SPRG_THREAD has |
108 | * the physical address of the current task thread_struct. | |
14cf11af PM |
109 | * Note that we have to have decremented r1 before we write to any fields |
110 | * of the exception frame, since a critical interrupt could occur at any | |
111 | * time, and it will write to the area immediately below the current r1. | |
112 | */ | |
113 | #define NORMAL_EXCEPTION_PROLOG \ | |
ee43eb78 BH |
114 | mtspr SPRN_SPRG_SCRATCH0,r10; /* save two registers to work with */\ |
115 | mtspr SPRN_SPRG_SCRATCH1,r11; \ | |
116 | mtspr SPRN_SPRG_SCRATCH2,r1; \ | |
14cf11af PM |
117 | mfcr r10; /* save CR in r10 for now */\ |
118 | mfspr r11,SPRN_SRR1; /* check whether user or kernel */\ | |
119 | andi. r11,r11,MSR_PR; \ | |
120 | beq 1f; \ | |
ee43eb78 | 121 | mfspr r1,SPRN_SPRG_THREAD; /* if from user, start at top of */\ |
14cf11af PM |
122 | lwz r1,THREAD_INFO-THREAD(r1); /* this thread's kernel stack */\ |
123 | addi r1,r1,THREAD_SIZE; \ | |
124 | 1: subi r1,r1,INT_FRAME_SIZE; /* Allocate an exception frame */\ | |
125 | tophys(r11,r1); \ | |
126 | stw r10,_CCR(r11); /* save various registers */\ | |
127 | stw r12,GPR12(r11); \ | |
128 | stw r9,GPR9(r11); \ | |
ee43eb78 | 129 | mfspr r10,SPRN_SPRG_SCRATCH0; \ |
14cf11af | 130 | stw r10,GPR10(r11); \ |
ee43eb78 | 131 | mfspr r12,SPRN_SPRG_SCRATCH1; \ |
14cf11af PM |
132 | stw r12,GPR11(r11); \ |
133 | mflr r10; \ | |
134 | stw r10,_LINK(r11); \ | |
ee43eb78 | 135 | mfspr r10,SPRN_SPRG_SCRATCH2; \ |
14cf11af PM |
136 | mfspr r12,SPRN_SRR0; \ |
137 | stw r10,GPR1(r11); \ | |
138 | mfspr r9,SPRN_SRR1; \ | |
139 | stw r10,0(r11); \ | |
140 | rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\ | |
141 | stw r0,GPR0(r11); \ | |
142 | SAVE_4GPRS(3, r11); \ | |
143 | SAVE_2GPRS(7, r11) | |
144 | ||
145 | /* | |
146 | * Exception prolog for critical exceptions. This is a little different | |
147 | * from the normal exception prolog above since a critical exception | |
148 | * can potentially occur at any point during normal exception processing. | |
149 | * Thus we cannot use the same SPRG registers as the normal prolog above. | |
150 | * Instead we use a couple of words of memory at low physical addresses. | |
151 | * This is OK since we don't support SMP on these processors. | |
152 | */ | |
153 | #define CRITICAL_EXCEPTION_PROLOG \ | |
154 | stw r10,crit_r10@l(0); /* save two registers to work with */\ | |
155 | stw r11,crit_r11@l(0); \ | |
156 | mfcr r10; /* save CR in r10 for now */\ | |
157 | mfspr r11,SPRN_SRR3; /* check whether user or kernel */\ | |
158 | andi. r11,r11,MSR_PR; \ | |
bcf0b088 KG |
159 | lis r11,critirq_ctx@ha; \ |
160 | tophys(r11,r11); \ | |
161 | lwz r11,critirq_ctx@l(r11); \ | |
14cf11af PM |
162 | beq 1f; \ |
163 | /* COMING FROM USER MODE */ \ | |
ee43eb78 | 164 | mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\ |
14cf11af | 165 | lwz r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\ |
bcf0b088 | 166 | 1: addi r11,r11,THREAD_SIZE-INT_FRAME_SIZE; /* Alloc an excpt frm */\ |
14cf11af PM |
167 | tophys(r11,r11); \ |
168 | stw r10,_CCR(r11); /* save various registers */\ | |
169 | stw r12,GPR12(r11); \ | |
170 | stw r9,GPR9(r11); \ | |
171 | mflr r10; \ | |
172 | stw r10,_LINK(r11); \ | |
173 | mfspr r12,SPRN_DEAR; /* save DEAR and ESR in the frame */\ | |
174 | stw r12,_DEAR(r11); /* since they may have had stuff */\ | |
175 | mfspr r9,SPRN_ESR; /* in them at the point where the */\ | |
176 | stw r9,_ESR(r11); /* exception was taken */\ | |
177 | mfspr r12,SPRN_SRR2; \ | |
178 | stw r1,GPR1(r11); \ | |
179 | mfspr r9,SPRN_SRR3; \ | |
180 | stw r1,0(r11); \ | |
181 | tovirt(r1,r11); \ | |
182 | rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\ | |
183 | stw r0,GPR0(r11); \ | |
184 | SAVE_4GPRS(3, r11); \ | |
185 | SAVE_2GPRS(7, r11) | |
186 | ||
187 | /* | |
188 | * State at this point: | |
189 | * r9 saved in stack frame, now saved SRR3 & ~MSR_WE | |
190 | * r10 saved in crit_r10 and in stack frame, trashed | |
191 | * r11 saved in crit_r11 and in stack frame, | |
192 | * now phys stack/exception frame pointer | |
193 | * r12 saved in stack frame, now saved SRR2 | |
194 | * CR saved in stack frame, CR0.EQ = !SRR3.PR | |
195 | * LR, DEAR, ESR in stack frame | |
196 | * r1 saved in stack frame, now virt stack/excframe pointer | |
197 | * r0, r3-r8 saved in stack frame | |
198 | */ | |
199 | ||
200 | /* | |
201 | * Exception vectors. | |
202 | */ | |
203 | #define START_EXCEPTION(n, label) \ | |
204 | . = n; \ | |
205 | label: | |
206 | ||
207 | #define EXCEPTION(n, label, hdlr, xfer) \ | |
208 | START_EXCEPTION(n, label); \ | |
209 | NORMAL_EXCEPTION_PROLOG; \ | |
210 | addi r3,r1,STACK_FRAME_OVERHEAD; \ | |
211 | xfer(n, hdlr) | |
212 | ||
213 | #define CRITICAL_EXCEPTION(n, label, hdlr) \ | |
214 | START_EXCEPTION(n, label); \ | |
215 | CRITICAL_EXCEPTION_PROLOG; \ | |
216 | addi r3,r1,STACK_FRAME_OVERHEAD; \ | |
217 | EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \ | |
218 | NOCOPY, crit_transfer_to_handler, \ | |
219 | ret_from_crit_exc) | |
220 | ||
221 | #define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret) \ | |
222 | li r10,trap; \ | |
d73e0c99 | 223 | stw r10,_TRAP(r11); \ |
14cf11af PM |
224 | lis r10,msr@h; \ |
225 | ori r10,r10,msr@l; \ | |
226 | copyee(r10, r9); \ | |
227 | bl tfer; \ | |
228 | .long hdlr; \ | |
229 | .long ret | |
230 | ||
231 | #define COPY_EE(d, s) rlwimi d,s,0,16,16 | |
232 | #define NOCOPY(d, s) | |
233 | ||
234 | #define EXC_XFER_STD(n, hdlr) \ | |
235 | EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full, \ | |
236 | ret_from_except_full) | |
237 | ||
238 | #define EXC_XFER_LITE(n, hdlr) \ | |
239 | EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \ | |
240 | ret_from_except) | |
241 | ||
242 | #define EXC_XFER_EE(n, hdlr) \ | |
243 | EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \ | |
244 | ret_from_except_full) | |
245 | ||
246 | #define EXC_XFER_EE_LITE(n, hdlr) \ | |
247 | EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \ | |
248 | ret_from_except) | |
249 | ||
250 | ||
251 | /* | |
252 | * 0x0100 - Critical Interrupt Exception | |
253 | */ | |
dc1c1ca3 | 254 | CRITICAL_EXCEPTION(0x0100, CriticalInterrupt, unknown_exception) |
14cf11af PM |
255 | |
256 | /* | |
257 | * 0x0200 - Machine Check Exception | |
258 | */ | |
dc1c1ca3 | 259 | CRITICAL_EXCEPTION(0x0200, MachineCheck, machine_check_exception) |
14cf11af PM |
260 | |
261 | /* | |
262 | * 0x0300 - Data Storage Exception | |
263 | * This happens for just a few reasons. U0 set (but we don't do that), | |
264 | * or zone protection fault (user violation, write to protected page). | |
265 | * If this is just an update of modified status, we do that quickly | |
266 | * and exit. Otherwise, we call heavywight functions to do the work. | |
267 | */ | |
268 | START_EXCEPTION(0x0300, DataStorage) | |
ee43eb78 BH |
269 | mtspr SPRN_SPRG_SCRATCH0, r10 /* Save some working registers */ |
270 | mtspr SPRN_SPRG_SCRATCH1, r11 | |
14cf11af PM |
271 | #ifdef CONFIG_403GCX |
272 | stw r12, 0(r0) | |
273 | stw r9, 4(r0) | |
274 | mfcr r11 | |
275 | mfspr r12, SPRN_PID | |
276 | stw r11, 8(r0) | |
277 | stw r12, 12(r0) | |
278 | #else | |
ee43eb78 BH |
279 | mtspr SPRN_SPRG_SCRATCH3, r12 |
280 | mtspr SPRN_SPRG_SCRATCH4, r9 | |
14cf11af PM |
281 | mfcr r11 |
282 | mfspr r12, SPRN_PID | |
ee43eb78 BH |
283 | mtspr SPRN_SPRG_SCRATCH6, r11 |
284 | mtspr SPRN_SPRG_SCRATCH5, r12 | |
14cf11af PM |
285 | #endif |
286 | ||
287 | /* First, check if it was a zone fault (which means a user | |
288 | * tried to access a kernel or read-protected page - always | |
289 | * a SEGV). All other faults here must be stores, so no | |
290 | * need to check ESR_DST as well. */ | |
291 | mfspr r10, SPRN_ESR | |
292 | andis. r10, r10, ESR_DIZ@h | |
293 | bne 2f | |
294 | ||
295 | mfspr r10, SPRN_DEAR /* Get faulting address */ | |
296 | ||
297 | /* If we are faulting a kernel address, we have to use the | |
298 | * kernel page tables. | |
299 | */ | |
8a13c4f9 | 300 | lis r11, PAGE_OFFSET@h |
14cf11af PM |
301 | cmplw r10, r11 |
302 | blt+ 3f | |
303 | lis r11, swapper_pg_dir@h | |
304 | ori r11, r11, swapper_pg_dir@l | |
305 | li r9, 0 | |
306 | mtspr SPRN_PID, r9 /* TLB will have 0 TID */ | |
307 | b 4f | |
308 | ||
309 | /* Get the PGD for the current thread. | |
310 | */ | |
311 | 3: | |
ee43eb78 | 312 | mfspr r11,SPRN_SPRG_THREAD |
14cf11af PM |
313 | lwz r11,PGDIR(r11) |
314 | 4: | |
315 | tophys(r11, r11) | |
316 | rlwimi r11, r10, 12, 20, 29 /* Create L1 (pgdir/pmd) address */ | |
317 | lwz r11, 0(r11) /* Get L1 entry */ | |
318 | rlwinm. r12, r11, 0, 0, 19 /* Extract L2 (pte) base address */ | |
319 | beq 2f /* Bail if no table */ | |
320 | ||
321 | rlwimi r12, r10, 22, 20, 29 /* Compute PTE address */ | |
322 | lwz r11, 0(r12) /* Get Linux PTE */ | |
323 | ||
324 | andi. r9, r11, _PAGE_RW /* Is it writeable? */ | |
325 | beq 2f /* Bail if not */ | |
326 | ||
327 | /* Update 'changed'. | |
328 | */ | |
329 | ori r11, r11, _PAGE_DIRTY|_PAGE_ACCESSED|_PAGE_HWWRITE | |
330 | stw r11, 0(r12) /* Update Linux page table */ | |
331 | ||
332 | /* Most of the Linux PTE is ready to load into the TLB LO. | |
333 | * We set ZSEL, where only the LS-bit determines user access. | |
334 | * We set execute, because we don't have the granularity to | |
335 | * properly set this at the page level (Linux problem). | |
336 | * If shared is set, we cause a zero PID->TID load. | |
337 | * Many of these bits are software only. Bits we don't set | |
338 | * here we (properly should) assume have the appropriate value. | |
339 | */ | |
340 | li r12, 0x0ce2 | |
341 | andc r11, r11, r12 /* Make sure 20, 21 are zero */ | |
342 | ||
343 | /* find the TLB index that caused the fault. It has to be here. | |
344 | */ | |
345 | tlbsx r9, 0, r10 | |
346 | ||
347 | tlbwe r11, r9, TLB_DATA /* Load TLB LO */ | |
348 | ||
349 | /* Done...restore registers and get out of here. | |
350 | */ | |
351 | #ifdef CONFIG_403GCX | |
352 | lwz r12, 12(r0) | |
353 | lwz r11, 8(r0) | |
354 | mtspr SPRN_PID, r12 | |
355 | mtcr r11 | |
356 | lwz r9, 4(r0) | |
357 | lwz r12, 0(r0) | |
358 | #else | |
ee43eb78 BH |
359 | mfspr r12, SPRN_SPRG_SCRATCH5 |
360 | mfspr r11, SPRN_SPRG_SCRATCH6 | |
14cf11af PM |
361 | mtspr SPRN_PID, r12 |
362 | mtcr r11 | |
ee43eb78 BH |
363 | mfspr r9, SPRN_SPRG_SCRATCH4 |
364 | mfspr r12, SPRN_SPRG_SCRATCH3 | |
14cf11af | 365 | #endif |
ee43eb78 BH |
366 | mfspr r11, SPRN_SPRG_SCRATCH1 |
367 | mfspr r10, SPRN_SPRG_SCRATCH0 | |
14cf11af PM |
368 | PPC405_ERR77_SYNC |
369 | rfi /* Should sync shadow TLBs */ | |
370 | b . /* prevent prefetch past rfi */ | |
371 | ||
372 | 2: | |
373 | /* The bailout. Restore registers to pre-exception conditions | |
374 | * and call the heavyweights to help us out. | |
375 | */ | |
376 | #ifdef CONFIG_403GCX | |
377 | lwz r12, 12(r0) | |
378 | lwz r11, 8(r0) | |
379 | mtspr SPRN_PID, r12 | |
380 | mtcr r11 | |
381 | lwz r9, 4(r0) | |
382 | lwz r12, 0(r0) | |
383 | #else | |
ee43eb78 BH |
384 | mfspr r12, SPRN_SPRG_SCRATCH5 |
385 | mfspr r11, SPRN_SPRG_SCRATCH6 | |
14cf11af PM |
386 | mtspr SPRN_PID, r12 |
387 | mtcr r11 | |
ee43eb78 BH |
388 | mfspr r9, SPRN_SPRG_SCRATCH4 |
389 | mfspr r12, SPRN_SPRG_SCRATCH3 | |
14cf11af | 390 | #endif |
ee43eb78 BH |
391 | mfspr r11, SPRN_SPRG_SCRATCH1 |
392 | mfspr r10, SPRN_SPRG_SCRATCH0 | |
14cf11af PM |
393 | b DataAccess |
394 | ||
395 | /* | |
396 | * 0x0400 - Instruction Storage Exception | |
397 | * This is caused by a fetch from non-execute or guarded pages. | |
398 | */ | |
399 | START_EXCEPTION(0x0400, InstructionAccess) | |
400 | NORMAL_EXCEPTION_PROLOG | |
401 | mr r4,r12 /* Pass SRR0 as arg2 */ | |
402 | li r5,0 /* Pass zero as arg3 */ | |
403 | EXC_XFER_EE_LITE(0x400, handle_page_fault) | |
404 | ||
405 | /* 0x0500 - External Interrupt Exception */ | |
406 | EXCEPTION(0x0500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE) | |
407 | ||
408 | /* 0x0600 - Alignment Exception */ | |
409 | START_EXCEPTION(0x0600, Alignment) | |
410 | NORMAL_EXCEPTION_PROLOG | |
411 | mfspr r4,SPRN_DEAR /* Grab the DEAR and save it */ | |
412 | stw r4,_DEAR(r11) | |
413 | addi r3,r1,STACK_FRAME_OVERHEAD | |
dc1c1ca3 | 414 | EXC_XFER_EE(0x600, alignment_exception) |
14cf11af PM |
415 | |
416 | /* 0x0700 - Program Exception */ | |
417 | START_EXCEPTION(0x0700, ProgramCheck) | |
418 | NORMAL_EXCEPTION_PROLOG | |
419 | mfspr r4,SPRN_ESR /* Grab the ESR and save it */ | |
420 | stw r4,_ESR(r11) | |
421 | addi r3,r1,STACK_FRAME_OVERHEAD | |
dc1c1ca3 | 422 | EXC_XFER_STD(0x700, program_check_exception) |
14cf11af | 423 | |
dc1c1ca3 SR |
424 | EXCEPTION(0x0800, Trap_08, unknown_exception, EXC_XFER_EE) |
425 | EXCEPTION(0x0900, Trap_09, unknown_exception, EXC_XFER_EE) | |
426 | EXCEPTION(0x0A00, Trap_0A, unknown_exception, EXC_XFER_EE) | |
427 | EXCEPTION(0x0B00, Trap_0B, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
428 | |
429 | /* 0x0C00 - System Call Exception */ | |
430 | START_EXCEPTION(0x0C00, SystemCall) | |
431 | NORMAL_EXCEPTION_PROLOG | |
432 | EXC_XFER_EE_LITE(0xc00, DoSyscall) | |
433 | ||
dc1c1ca3 SR |
434 | EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_EE) |
435 | EXCEPTION(0x0E00, Trap_0E, unknown_exception, EXC_XFER_EE) | |
436 | EXCEPTION(0x0F00, Trap_0F, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
437 | |
438 | /* 0x1000 - Programmable Interval Timer (PIT) Exception */ | |
439 | START_EXCEPTION(0x1000, Decrementer) | |
440 | NORMAL_EXCEPTION_PROLOG | |
441 | lis r0,TSR_PIS@h | |
442 | mtspr SPRN_TSR,r0 /* Clear the PIT exception */ | |
443 | addi r3,r1,STACK_FRAME_OVERHEAD | |
444 | EXC_XFER_LITE(0x1000, timer_interrupt) | |
445 | ||
446 | #if 0 | |
447 | /* NOTE: | |
448 | * FIT and WDT handlers are not implemented yet. | |
449 | */ | |
450 | ||
451 | /* 0x1010 - Fixed Interval Timer (FIT) Exception | |
452 | */ | |
dc1c1ca3 | 453 | STND_EXCEPTION(0x1010, FITException, unknown_exception) |
14cf11af PM |
454 | |
455 | /* 0x1020 - Watchdog Timer (WDT) Exception | |
456 | */ | |
457 | #ifdef CONFIG_BOOKE_WDT | |
458 | CRITICAL_EXCEPTION(0x1020, WDTException, WatchdogException) | |
459 | #else | |
dc1c1ca3 | 460 | CRITICAL_EXCEPTION(0x1020, WDTException, unknown_exception) |
14cf11af PM |
461 | #endif |
462 | #endif | |
463 | ||
464 | /* 0x1100 - Data TLB Miss Exception | |
465 | * As the name implies, translation is not in the MMU, so search the | |
466 | * page tables and fix it. The only purpose of this function is to | |
467 | * load TLB entries from the page table if they exist. | |
468 | */ | |
469 | START_EXCEPTION(0x1100, DTLBMiss) | |
ee43eb78 BH |
470 | mtspr SPRN_SPRG_SCRATCH0, r10 /* Save some working registers */ |
471 | mtspr SPRN_SPRG_SCRATCH1, r11 | |
14cf11af PM |
472 | #ifdef CONFIG_403GCX |
473 | stw r12, 0(r0) | |
474 | stw r9, 4(r0) | |
475 | mfcr r11 | |
476 | mfspr r12, SPRN_PID | |
477 | stw r11, 8(r0) | |
478 | stw r12, 12(r0) | |
479 | #else | |
ee43eb78 BH |
480 | mtspr SPRN_SPRG_SCRATCH3, r12 |
481 | mtspr SPRN_SPRG_SCRATCH4, r9 | |
14cf11af PM |
482 | mfcr r11 |
483 | mfspr r12, SPRN_PID | |
ee43eb78 BH |
484 | mtspr SPRN_SPRG_SCRATCH6, r11 |
485 | mtspr SPRN_SPRG_SCRATCH5, r12 | |
14cf11af PM |
486 | #endif |
487 | mfspr r10, SPRN_DEAR /* Get faulting address */ | |
488 | ||
489 | /* If we are faulting a kernel address, we have to use the | |
490 | * kernel page tables. | |
491 | */ | |
8a13c4f9 | 492 | lis r11, PAGE_OFFSET@h |
14cf11af PM |
493 | cmplw r10, r11 |
494 | blt+ 3f | |
495 | lis r11, swapper_pg_dir@h | |
496 | ori r11, r11, swapper_pg_dir@l | |
497 | li r9, 0 | |
498 | mtspr SPRN_PID, r9 /* TLB will have 0 TID */ | |
499 | b 4f | |
500 | ||
501 | /* Get the PGD for the current thread. | |
502 | */ | |
503 | 3: | |
ee43eb78 | 504 | mfspr r11,SPRN_SPRG_THREAD |
14cf11af PM |
505 | lwz r11,PGDIR(r11) |
506 | 4: | |
507 | tophys(r11, r11) | |
508 | rlwimi r11, r10, 12, 20, 29 /* Create L1 (pgdir/pmd) address */ | |
509 | lwz r12, 0(r11) /* Get L1 entry */ | |
510 | andi. r9, r12, _PMD_PRESENT /* Check if it points to a PTE page */ | |
511 | beq 2f /* Bail if no table */ | |
512 | ||
513 | rlwimi r12, r10, 22, 20, 29 /* Compute PTE address */ | |
514 | lwz r11, 0(r12) /* Get Linux PTE */ | |
515 | andi. r9, r11, _PAGE_PRESENT | |
516 | beq 5f | |
517 | ||
518 | ori r11, r11, _PAGE_ACCESSED | |
519 | stw r11, 0(r12) | |
520 | ||
521 | /* Create TLB tag. This is the faulting address plus a static | |
522 | * set of bits. These are size, valid, E, U0. | |
523 | */ | |
524 | li r12, 0x00c0 | |
525 | rlwimi r10, r12, 0, 20, 31 | |
526 | ||
527 | b finish_tlb_load | |
528 | ||
529 | 2: /* Check for possible large-page pmd entry */ | |
530 | rlwinm. r9, r12, 2, 22, 24 | |
531 | beq 5f | |
532 | ||
533 | /* Create TLB tag. This is the faulting address, plus a static | |
534 | * set of bits (valid, E, U0) plus the size from the PMD. | |
535 | */ | |
536 | ori r9, r9, 0x40 | |
537 | rlwimi r10, r9, 0, 20, 31 | |
538 | mr r11, r12 | |
539 | ||
540 | b finish_tlb_load | |
541 | ||
542 | 5: | |
543 | /* The bailout. Restore registers to pre-exception conditions | |
544 | * and call the heavyweights to help us out. | |
545 | */ | |
546 | #ifdef CONFIG_403GCX | |
547 | lwz r12, 12(r0) | |
548 | lwz r11, 8(r0) | |
549 | mtspr SPRN_PID, r12 | |
550 | mtcr r11 | |
551 | lwz r9, 4(r0) | |
552 | lwz r12, 0(r0) | |
553 | #else | |
ee43eb78 BH |
554 | mfspr r12, SPRN_SPRG_SCRATCH5 |
555 | mfspr r11, SPRN_SPRG_SCRATCH6 | |
14cf11af PM |
556 | mtspr SPRN_PID, r12 |
557 | mtcr r11 | |
ee43eb78 BH |
558 | mfspr r9, SPRN_SPRG_SCRATCH4 |
559 | mfspr r12, SPRN_SPRG_SCRATCH3 | |
14cf11af | 560 | #endif |
ee43eb78 BH |
561 | mfspr r11, SPRN_SPRG_SCRATCH1 |
562 | mfspr r10, SPRN_SPRG_SCRATCH0 | |
14cf11af PM |
563 | b DataAccess |
564 | ||
565 | /* 0x1200 - Instruction TLB Miss Exception | |
566 | * Nearly the same as above, except we get our information from different | |
567 | * registers and bailout to a different point. | |
568 | */ | |
569 | START_EXCEPTION(0x1200, ITLBMiss) | |
ee43eb78 BH |
570 | mtspr SPRN_SPRG_SCRATCH0, r10 /* Save some working registers */ |
571 | mtspr SPRN_SPRG_SCRATCH1, r11 | |
14cf11af PM |
572 | #ifdef CONFIG_403GCX |
573 | stw r12, 0(r0) | |
574 | stw r9, 4(r0) | |
575 | mfcr r11 | |
576 | mfspr r12, SPRN_PID | |
577 | stw r11, 8(r0) | |
578 | stw r12, 12(r0) | |
579 | #else | |
ee43eb78 BH |
580 | mtspr SPRN_SPRG_SCRATCH3, r12 |
581 | mtspr SPRN_SPRG_SCRATCH4, r9 | |
14cf11af PM |
582 | mfcr r11 |
583 | mfspr r12, SPRN_PID | |
ee43eb78 BH |
584 | mtspr SPRN_SPRG_SCRATCH6, r11 |
585 | mtspr SPRN_SPRG_SCRATCH5, r12 | |
14cf11af PM |
586 | #endif |
587 | mfspr r10, SPRN_SRR0 /* Get faulting address */ | |
588 | ||
589 | /* If we are faulting a kernel address, we have to use the | |
590 | * kernel page tables. | |
591 | */ | |
8a13c4f9 | 592 | lis r11, PAGE_OFFSET@h |
14cf11af PM |
593 | cmplw r10, r11 |
594 | blt+ 3f | |
595 | lis r11, swapper_pg_dir@h | |
596 | ori r11, r11, swapper_pg_dir@l | |
597 | li r9, 0 | |
598 | mtspr SPRN_PID, r9 /* TLB will have 0 TID */ | |
599 | b 4f | |
600 | ||
601 | /* Get the PGD for the current thread. | |
602 | */ | |
603 | 3: | |
ee43eb78 | 604 | mfspr r11,SPRN_SPRG_THREAD |
14cf11af PM |
605 | lwz r11,PGDIR(r11) |
606 | 4: | |
607 | tophys(r11, r11) | |
608 | rlwimi r11, r10, 12, 20, 29 /* Create L1 (pgdir/pmd) address */ | |
609 | lwz r12, 0(r11) /* Get L1 entry */ | |
610 | andi. r9, r12, _PMD_PRESENT /* Check if it points to a PTE page */ | |
611 | beq 2f /* Bail if no table */ | |
612 | ||
613 | rlwimi r12, r10, 22, 20, 29 /* Compute PTE address */ | |
614 | lwz r11, 0(r12) /* Get Linux PTE */ | |
615 | andi. r9, r11, _PAGE_PRESENT | |
616 | beq 5f | |
617 | ||
618 | ori r11, r11, _PAGE_ACCESSED | |
619 | stw r11, 0(r12) | |
620 | ||
621 | /* Create TLB tag. This is the faulting address plus a static | |
622 | * set of bits. These are size, valid, E, U0. | |
623 | */ | |
624 | li r12, 0x00c0 | |
625 | rlwimi r10, r12, 0, 20, 31 | |
626 | ||
627 | b finish_tlb_load | |
628 | ||
629 | 2: /* Check for possible large-page pmd entry */ | |
630 | rlwinm. r9, r12, 2, 22, 24 | |
631 | beq 5f | |
632 | ||
633 | /* Create TLB tag. This is the faulting address, plus a static | |
634 | * set of bits (valid, E, U0) plus the size from the PMD. | |
635 | */ | |
636 | ori r9, r9, 0x40 | |
637 | rlwimi r10, r9, 0, 20, 31 | |
638 | mr r11, r12 | |
639 | ||
640 | b finish_tlb_load | |
641 | ||
642 | 5: | |
643 | /* The bailout. Restore registers to pre-exception conditions | |
644 | * and call the heavyweights to help us out. | |
645 | */ | |
646 | #ifdef CONFIG_403GCX | |
647 | lwz r12, 12(r0) | |
648 | lwz r11, 8(r0) | |
649 | mtspr SPRN_PID, r12 | |
650 | mtcr r11 | |
651 | lwz r9, 4(r0) | |
652 | lwz r12, 0(r0) | |
653 | #else | |
ee43eb78 BH |
654 | mfspr r12, SPRN_SPRG_SCRATCH5 |
655 | mfspr r11, SPRN_SPRG_SCRATCH6 | |
14cf11af PM |
656 | mtspr SPRN_PID, r12 |
657 | mtcr r11 | |
ee43eb78 BH |
658 | mfspr r9, SPRN_SPRG_SCRATCH4 |
659 | mfspr r12, SPRN_SPRG_SCRATCH3 | |
14cf11af | 660 | #endif |
ee43eb78 BH |
661 | mfspr r11, SPRN_SPRG_SCRATCH1 |
662 | mfspr r10, SPRN_SPRG_SCRATCH0 | |
14cf11af PM |
663 | b InstructionAccess |
664 | ||
dc1c1ca3 SR |
665 | EXCEPTION(0x1300, Trap_13, unknown_exception, EXC_XFER_EE) |
666 | EXCEPTION(0x1400, Trap_14, unknown_exception, EXC_XFER_EE) | |
667 | EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE) | |
668 | EXCEPTION(0x1600, Trap_16, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
669 | #ifdef CONFIG_IBM405_ERR51 |
670 | /* 405GP errata 51 */ | |
671 | START_EXCEPTION(0x1700, Trap_17) | |
672 | b DTLBMiss | |
673 | #else | |
dc1c1ca3 | 674 | EXCEPTION(0x1700, Trap_17, unknown_exception, EXC_XFER_EE) |
14cf11af | 675 | #endif |
dc1c1ca3 SR |
676 | EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE) |
677 | EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE) | |
678 | EXCEPTION(0x1A00, Trap_1A, unknown_exception, EXC_XFER_EE) | |
679 | EXCEPTION(0x1B00, Trap_1B, unknown_exception, EXC_XFER_EE) | |
680 | EXCEPTION(0x1C00, Trap_1C, unknown_exception, EXC_XFER_EE) | |
681 | EXCEPTION(0x1D00, Trap_1D, unknown_exception, EXC_XFER_EE) | |
682 | EXCEPTION(0x1E00, Trap_1E, unknown_exception, EXC_XFER_EE) | |
683 | EXCEPTION(0x1F00, Trap_1F, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
684 | |
685 | /* Check for a single step debug exception while in an exception | |
686 | * handler before state has been saved. This is to catch the case | |
687 | * where an instruction that we are trying to single step causes | |
688 | * an exception (eg ITLB/DTLB miss) and thus the first instruction of | |
689 | * the exception handler generates a single step debug exception. | |
690 | * | |
691 | * If we get a debug trap on the first instruction of an exception handler, | |
692 | * we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is | |
693 | * a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR). | |
694 | * The exception handler was handling a non-critical interrupt, so it will | |
695 | * save (and later restore) the MSR via SPRN_SRR1, which will still have | |
696 | * the MSR_DE bit set. | |
697 | */ | |
698 | /* 0x2000 - Debug Exception */ | |
699 | START_EXCEPTION(0x2000, DebugTrap) | |
700 | CRITICAL_EXCEPTION_PROLOG | |
701 | ||
702 | /* | |
703 | * If this is a single step or branch-taken exception in an | |
704 | * exception entry sequence, it was probably meant to apply to | |
705 | * the code where the exception occurred (since exception entry | |
706 | * doesn't turn off DE automatically). We simulate the effect | |
707 | * of turning off DE on entry to an exception handler by turning | |
708 | * off DE in the SRR3 value and clearing the debug status. | |
709 | */ | |
710 | mfspr r10,SPRN_DBSR /* check single-step/branch taken */ | |
711 | andis. r10,r10,DBSR_IC@h | |
712 | beq+ 2f | |
713 | ||
714 | andi. r10,r9,MSR_IR|MSR_PR /* check supervisor + MMU off */ | |
715 | beq 1f /* branch and fix it up */ | |
716 | ||
717 | mfspr r10,SPRN_SRR2 /* Faulting instruction address */ | |
718 | cmplwi r10,0x2100 | |
719 | bgt+ 2f /* address above exception vectors */ | |
720 | ||
721 | /* here it looks like we got an inappropriate debug exception. */ | |
722 | 1: rlwinm r9,r9,0,~MSR_DE /* clear DE in the SRR3 value */ | |
723 | lis r10,DBSR_IC@h /* clear the IC event */ | |
724 | mtspr SPRN_DBSR,r10 | |
725 | /* restore state and get out */ | |
726 | lwz r10,_CCR(r11) | |
727 | lwz r0,GPR0(r11) | |
728 | lwz r1,GPR1(r11) | |
729 | mtcrf 0x80,r10 | |
730 | mtspr SPRN_SRR2,r12 | |
731 | mtspr SPRN_SRR3,r9 | |
732 | lwz r9,GPR9(r11) | |
733 | lwz r12,GPR12(r11) | |
734 | lwz r10,crit_r10@l(0) | |
735 | lwz r11,crit_r11@l(0) | |
736 | PPC405_ERR77_SYNC | |
737 | rfci | |
738 | b . | |
739 | ||
740 | /* continue normal handling for a critical exception... */ | |
741 | 2: mfspr r4,SPRN_DBSR | |
742 | addi r3,r1,STACK_FRAME_OVERHEAD | |
743 | EXC_XFER_TEMPLATE(DebugException, 0x2002, \ | |
744 | (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \ | |
745 | NOCOPY, crit_transfer_to_handler, ret_from_crit_exc) | |
746 | ||
747 | /* | |
748 | * The other Data TLB exceptions bail out to this point | |
749 | * if they can't resolve the lightweight TLB fault. | |
750 | */ | |
751 | DataAccess: | |
752 | NORMAL_EXCEPTION_PROLOG | |
753 | mfspr r5,SPRN_ESR /* Grab the ESR, save it, pass arg3 */ | |
754 | stw r5,_ESR(r11) | |
755 | mfspr r4,SPRN_DEAR /* Grab the DEAR, save it, pass arg2 */ | |
756 | EXC_XFER_EE_LITE(0x300, handle_page_fault) | |
757 | ||
758 | /* Other PowerPC processors, namely those derived from the 6xx-series | |
759 | * have vectors from 0x2100 through 0x2F00 defined, but marked as reserved. | |
760 | * However, for the 4xx-series processors these are neither defined nor | |
761 | * reserved. | |
762 | */ | |
763 | ||
764 | /* Damn, I came up one instruction too many to fit into the | |
765 | * exception space :-). Both the instruction and data TLB | |
766 | * miss get to this point to load the TLB. | |
767 | * r10 - TLB_TAG value | |
768 | * r11 - Linux PTE | |
25985edc | 769 | * r12, r9 - available to use |
14cf11af PM |
770 | * PID - loaded with proper value when we get here |
771 | * Upon exit, we reload everything and RFI. | |
772 | * Actually, it will fit now, but oh well.....a common place | |
773 | * to load the TLB. | |
774 | */ | |
775 | tlb_4xx_index: | |
776 | .long 0 | |
777 | finish_tlb_load: | |
778 | /* load the next available TLB index. | |
779 | */ | |
780 | lwz r9, tlb_4xx_index@l(0) | |
781 | addi r9, r9, 1 | |
4d922c8d | 782 | andi. r9, r9, (PPC40X_TLB_SIZE-1) |
14cf11af PM |
783 | stw r9, tlb_4xx_index@l(0) |
784 | ||
785 | 6: | |
786 | /* | |
787 | * Clear out the software-only bits in the PTE to generate the | |
788 | * TLB_DATA value. These are the bottom 2 bits of the RPM, the | |
789 | * top 3 bits of the zone field, and M. | |
790 | */ | |
791 | li r12, 0x0ce2 | |
792 | andc r11, r11, r12 | |
793 | ||
794 | tlbwe r11, r9, TLB_DATA /* Load TLB LO */ | |
795 | tlbwe r10, r9, TLB_TAG /* Load TLB HI */ | |
796 | ||
797 | /* Done...restore registers and get out of here. | |
798 | */ | |
799 | #ifdef CONFIG_403GCX | |
800 | lwz r12, 12(r0) | |
801 | lwz r11, 8(r0) | |
802 | mtspr SPRN_PID, r12 | |
803 | mtcr r11 | |
804 | lwz r9, 4(r0) | |
805 | lwz r12, 0(r0) | |
806 | #else | |
ee43eb78 BH |
807 | mfspr r12, SPRN_SPRG_SCRATCH5 |
808 | mfspr r11, SPRN_SPRG_SCRATCH6 | |
14cf11af PM |
809 | mtspr SPRN_PID, r12 |
810 | mtcr r11 | |
ee43eb78 BH |
811 | mfspr r9, SPRN_SPRG_SCRATCH4 |
812 | mfspr r12, SPRN_SPRG_SCRATCH3 | |
14cf11af | 813 | #endif |
ee43eb78 BH |
814 | mfspr r11, SPRN_SPRG_SCRATCH1 |
815 | mfspr r10, SPRN_SPRG_SCRATCH0 | |
14cf11af PM |
816 | PPC405_ERR77_SYNC |
817 | rfi /* Should sync shadow TLBs */ | |
818 | b . /* prevent prefetch past rfi */ | |
819 | ||
820 | /* extern void giveup_fpu(struct task_struct *prev) | |
821 | * | |
822 | * The PowerPC 4xx family of processors do not have an FPU, so this just | |
823 | * returns. | |
824 | */ | |
748a7683 | 825 | _ENTRY(giveup_fpu) |
14cf11af PM |
826 | blr |
827 | ||
828 | /* This is where the main kernel code starts. | |
829 | */ | |
830 | start_here: | |
831 | ||
832 | /* ptr to current */ | |
833 | lis r2,init_task@h | |
834 | ori r2,r2,init_task@l | |
835 | ||
836 | /* ptr to phys current thread */ | |
837 | tophys(r4,r2) | |
838 | addi r4,r4,THREAD /* init task's THREAD */ | |
ee43eb78 | 839 | mtspr SPRN_SPRG_THREAD,r4 |
14cf11af PM |
840 | |
841 | /* stack */ | |
842 | lis r1,init_thread_union@ha | |
843 | addi r1,r1,init_thread_union@l | |
844 | li r0,0 | |
845 | stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1) | |
846 | ||
847 | bl early_init /* We have to do this with MMU on */ | |
848 | ||
849 | /* | |
850 | * Decide what sort of machine this is and initialize the MMU. | |
851 | */ | |
852 | mr r3,r31 | |
853 | mr r4,r30 | |
854 | mr r5,r29 | |
855 | mr r6,r28 | |
856 | mr r7,r27 | |
857 | bl machine_init | |
858 | bl MMU_init | |
859 | ||
860 | /* Go back to running unmapped so we can load up new values | |
861 | * and change to using our exception vectors. | |
862 | * On the 4xx, all we have to do is invalidate the TLB to clear | |
863 | * the old 16M byte TLB mappings. | |
864 | */ | |
865 | lis r4,2f@h | |
866 | ori r4,r4,2f@l | |
867 | tophys(r4,r4) | |
868 | lis r3,(MSR_KERNEL & ~(MSR_IR|MSR_DR))@h | |
869 | ori r3,r3,(MSR_KERNEL & ~(MSR_IR|MSR_DR))@l | |
870 | mtspr SPRN_SRR0,r4 | |
871 | mtspr SPRN_SRR1,r3 | |
872 | rfi | |
873 | b . /* prevent prefetch past rfi */ | |
874 | ||
875 | /* Load up the kernel context */ | |
876 | 2: | |
877 | sync /* Flush to memory before changing TLB */ | |
878 | tlbia | |
879 | isync /* Flush shadow TLBs */ | |
880 | ||
881 | /* set up the PTE pointers for the Abatron bdiGDB. | |
882 | */ | |
883 | lis r6, swapper_pg_dir@h | |
884 | ori r6, r6, swapper_pg_dir@l | |
885 | lis r5, abatron_pteptrs@h | |
886 | ori r5, r5, abatron_pteptrs@l | |
887 | stw r5, 0xf0(r0) /* Must match your Abatron config file */ | |
888 | tophys(r5,r5) | |
889 | stw r6, 0(r5) | |
890 | ||
891 | /* Now turn on the MMU for real! */ | |
892 | lis r4,MSR_KERNEL@h | |
893 | ori r4,r4,MSR_KERNEL@l | |
894 | lis r3,start_kernel@h | |
895 | ori r3,r3,start_kernel@l | |
896 | mtspr SPRN_SRR0,r3 | |
897 | mtspr SPRN_SRR1,r4 | |
898 | rfi /* enable MMU and jump to start_kernel */ | |
899 | b . /* prevent prefetch past rfi */ | |
900 | ||
901 | /* Set up the initial MMU state so we can do the first level of | |
902 | * kernel initialization. This maps the first 16 MBytes of memory 1:1 | |
903 | * virtual to physical and more importantly sets the cache mode. | |
904 | */ | |
905 | initial_mmu: | |
906 | tlbia /* Invalidate all TLB entries */ | |
907 | isync | |
908 | ||
909 | /* We should still be executing code at physical address 0x0000xxxx | |
910 | * at this point. However, start_here is at virtual address | |
911 | * 0xC000xxxx. So, set up a TLB mapping to cover this once | |
912 | * translation is enabled. | |
913 | */ | |
914 | ||
915 | lis r3,KERNELBASE@h /* Load the kernel virtual address */ | |
916 | ori r3,r3,KERNELBASE@l | |
917 | tophys(r4,r3) /* Load the kernel physical address */ | |
918 | ||
919 | iccci r0,r3 /* Invalidate the i-cache before use */ | |
920 | ||
921 | /* Load the kernel PID. | |
922 | */ | |
923 | li r0,0 | |
924 | mtspr SPRN_PID,r0 | |
925 | sync | |
926 | ||
cd3db0c4 | 927 | /* Configure and load one entry into TLB slots 63 */ |
14cf11af PM |
928 | clrrwi r4,r4,10 /* Mask off the real page number */ |
929 | ori r4,r4,(TLB_WR | TLB_EX) /* Set the write and execute bits */ | |
930 | ||
931 | clrrwi r3,r3,10 /* Mask off the effective page number */ | |
932 | ori r3,r3,(TLB_VALID | TLB_PAGESZ(PAGESZ_16M)) | |
933 | ||
934 | li r0,63 /* TLB slot 63 */ | |
935 | ||
936 | tlbwe r4,r0,TLB_DATA /* Load the data portion of the entry */ | |
937 | tlbwe r3,r0,TLB_TAG /* Load the tag portion of the entry */ | |
938 | ||
939 | #if defined(CONFIG_SERIAL_TEXT_DEBUG) && defined(SERIAL_DEBUG_IO_BASE) | |
940 | ||
941 | /* Load a TLB entry for the UART, so that ppc4xx_progress() can use | |
942 | * the UARTs nice and early. We use a 4k real==virtual mapping. */ | |
943 | ||
944 | lis r3,SERIAL_DEBUG_IO_BASE@h | |
945 | ori r3,r3,SERIAL_DEBUG_IO_BASE@l | |
946 | mr r4,r3 | |
947 | clrrwi r4,r4,12 | |
948 | ori r4,r4,(TLB_WR|TLB_I|TLB_M|TLB_G) | |
949 | ||
950 | clrrwi r3,r3,12 | |
951 | ori r3,r3,(TLB_VALID | TLB_PAGESZ(PAGESZ_4K)) | |
952 | ||
953 | li r0,0 /* TLB slot 0 */ | |
954 | tlbwe r4,r0,TLB_DATA | |
955 | tlbwe r3,r0,TLB_TAG | |
956 | #endif /* CONFIG_SERIAL_DEBUG_TEXT && SERIAL_DEBUG_IO_BASE */ | |
957 | ||
958 | isync | |
959 | ||
960 | /* Establish the exception vector base | |
961 | */ | |
962 | lis r4,KERNELBASE@h /* EVPR only uses the high 16-bits */ | |
963 | tophys(r0,r4) /* Use the physical address */ | |
964 | mtspr SPRN_EVPR,r0 | |
965 | ||
966 | blr | |
967 | ||
968 | _GLOBAL(abort) | |
969 | mfspr r13,SPRN_DBCR0 | |
970 | oris r13,r13,DBCR0_RST_SYSTEM@h | |
971 | mtspr SPRN_DBCR0,r13 | |
972 | ||
973 | _GLOBAL(set_context) | |
974 | ||
975 | #ifdef CONFIG_BDI_SWITCH | |
976 | /* Context switch the PTE pointer for the Abatron BDI2000. | |
977 | * The PGDIR is the second parameter. | |
978 | */ | |
979 | lis r5, KERNELBASE@h | |
980 | lwz r5, 0xf0(r5) | |
981 | stw r4, 0x4(r5) | |
982 | #endif | |
983 | sync | |
984 | mtspr SPRN_PID,r3 | |
985 | isync /* Need an isync to flush shadow */ | |
986 | /* TLBs after changing PID */ | |
987 | blr | |
988 | ||
989 | /* We put a few things here that have to be page-aligned. This stuff | |
990 | * goes at the beginning of the data segment, which is page-aligned. | |
991 | */ | |
992 | .data | |
ea703ce2 KG |
993 | .align 12 |
994 | .globl sdata | |
995 | sdata: | |
996 | .globl empty_zero_page | |
997 | empty_zero_page: | |
14cf11af | 998 | .space 4096 |
ea703ce2 KG |
999 | .globl swapper_pg_dir |
1000 | swapper_pg_dir: | |
bee86f14 | 1001 | .space PGD_TABLE_SIZE |
14cf11af | 1002 | |
14cf11af PM |
1003 | /* Room for two PTE pointers, usually the kernel and current user pointers |
1004 | * to their respective root page table. | |
1005 | */ | |
1006 | abatron_pteptrs: | |
1007 | .space 8 |