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14cf11af | 1 | /* |
14cf11af PM |
2 | * PowerPC version |
3 | * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) | |
4 | * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP | |
5 | * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu> | |
6 | * Low-level exception handlers and MMU support | |
7 | * rewritten by Paul Mackerras. | |
8 | * Copyright (C) 1996 Paul Mackerras. | |
9 | * MPC8xx modifications by Dan Malek | |
10 | * Copyright (C) 1997 Dan Malek (dmalek@jlc.net). | |
11 | * | |
12 | * This file contains low-level support and setup for PowerPC 8xx | |
13 | * embedded processors, including trap and interrupt dispatch. | |
14 | * | |
15 | * This program is free software; you can redistribute it and/or | |
16 | * modify it under the terms of the GNU General Public License | |
17 | * as published by the Free Software Foundation; either version | |
18 | * 2 of the License, or (at your option) any later version. | |
19 | * | |
20 | */ | |
21 | ||
e7039845 | 22 | #include <linux/init.h> |
14cf11af PM |
23 | #include <asm/processor.h> |
24 | #include <asm/page.h> | |
25 | #include <asm/mmu.h> | |
26 | #include <asm/cache.h> | |
27 | #include <asm/pgtable.h> | |
28 | #include <asm/cputable.h> | |
29 | #include <asm/thread_info.h> | |
30 | #include <asm/ppc_asm.h> | |
31 | #include <asm/asm-offsets.h> | |
46f52210 | 32 | #include <asm/ptrace.h> |
f86ef74e | 33 | #include <asm/fixmap.h> |
9445aa1a | 34 | #include <asm/export.h> |
14cf11af PM |
35 | |
36 | /* Macro to make the code more readable. */ | |
37 | #ifdef CONFIG_8xx_CPU6 | |
d3e40262 LC |
38 | #define SPRN_MI_TWC_ADDR 0x2b80 |
39 | #define SPRN_MI_RPN_ADDR 0x2d80 | |
40 | #define SPRN_MD_TWC_ADDR 0x3b80 | |
41 | #define SPRN_MD_RPN_ADDR 0x3d80 | |
42 | ||
43 | #define MTSPR_CPU6(spr, reg, treg) \ | |
44 | li treg, spr##_ADDR; \ | |
45 | stw treg, 12(r0); \ | |
46 | lwz treg, 12(r0); \ | |
47 | mtspr spr, reg | |
14cf11af | 48 | #else |
d3e40262 LC |
49 | #define MTSPR_CPU6(spr, reg, treg) \ |
50 | mtspr spr, reg | |
14cf11af | 51 | #endif |
ac21951f | 52 | |
eeba1f7c LC |
53 | /* Macro to test if an address is a kernel address */ |
54 | #if CONFIG_TASK_SIZE <= 0x80000000 && CONFIG_PAGE_OFFSET >= 0x80000000 | |
55 | #define IS_KERNEL(tmp, addr) \ | |
56 | andis. tmp, addr, 0x8000 /* Address >= 0x80000000 */ | |
57 | #define BRANCH_UNLESS_KERNEL(label) beq label | |
58 | #else | |
59 | #define IS_KERNEL(tmp, addr) \ | |
60 | rlwinm tmp, addr, 16, 16, 31; \ | |
61 | cmpli cr0, tmp, PAGE_OFFSET >> 16 | |
62 | #define BRANCH_UNLESS_KERNEL(label) blt label | |
63 | #endif | |
64 | ||
65 | ||
ac21951f LC |
66 | /* |
67 | * Value for the bits that have fixed value in RPN entries. | |
68 | * Also used for tagging DAR for DTLBerror. | |
69 | */ | |
959d6173 LC |
70 | #ifdef CONFIG_PPC_16K_PAGES |
71 | #define RPN_PATTERN (0x00f0 | MD_SPS16K) | |
72 | #else | |
ac21951f | 73 | #define RPN_PATTERN 0x00f0 |
959d6173 | 74 | #endif |
ac21951f | 75 | |
4b914286 CL |
76 | #define PAGE_SHIFT_512K 19 |
77 | #define PAGE_SHIFT_8M 23 | |
78 | ||
e7039845 | 79 | __HEAD |
748a7683 KG |
80 | _ENTRY(_stext); |
81 | _ENTRY(_start); | |
14cf11af PM |
82 | |
83 | /* MPC8xx | |
84 | * This port was done on an MBX board with an 860. Right now I only | |
85 | * support an ELF compressed (zImage) boot from EPPC-Bug because the | |
86 | * code there loads up some registers before calling us: | |
87 | * r3: ptr to board info data | |
88 | * r4: initrd_start or if no initrd then 0 | |
89 | * r5: initrd_end - unused if r4 is 0 | |
90 | * r6: Start of command line string | |
91 | * r7: End of command line string | |
92 | * | |
93 | * I decided to use conditional compilation instead of checking PVR and | |
94 | * adding more processor specific branches around code I don't need. | |
95 | * Since this is an embedded processor, I also appreciate any memory | |
96 | * savings I can get. | |
97 | * | |
98 | * The MPC8xx does not have any BATs, but it supports large page sizes. | |
99 | * We first initialize the MMU to support 8M byte pages, then load one | |
100 | * entry into each of the instruction and data TLBs to map the first | |
101 | * 8M 1:1. I also mapped an additional I/O space 1:1 so we can get to | |
102 | * the "internal" processor registers before MMU_init is called. | |
103 | * | |
14cf11af PM |
104 | * -- Dan |
105 | */ | |
106 | .globl __start | |
107 | __start: | |
6dece0eb | 108 | mr r31,r3 /* save device tree ptr */ |
14cf11af PM |
109 | |
110 | /* We have to turn on the MMU right away so we get cache modes | |
111 | * set correctly. | |
112 | */ | |
113 | bl initial_mmu | |
114 | ||
115 | /* We now have the lower 8 Meg mapped into TLB entries, and the caches | |
116 | * ready to work. | |
117 | */ | |
118 | ||
119 | turn_on_mmu: | |
120 | mfmsr r0 | |
121 | ori r0,r0,MSR_DR|MSR_IR | |
122 | mtspr SPRN_SRR1,r0 | |
123 | lis r0,start_here@h | |
124 | ori r0,r0,start_here@l | |
125 | mtspr SPRN_SRR0,r0 | |
126 | SYNC | |
127 | rfi /* enables MMU */ | |
128 | ||
129 | /* | |
130 | * Exception entry code. This code runs with address translation | |
131 | * turned off, i.e. using physical addresses. | |
132 | * We assume sprg3 has the physical address of the current | |
133 | * task's thread_struct. | |
134 | */ | |
135 | #define EXCEPTION_PROLOG \ | |
92625d49 | 136 | EXCEPTION_PROLOG_0; \ |
d5fd9d7d | 137 | mfcr r10; \ |
14cf11af PM |
138 | EXCEPTION_PROLOG_1; \ |
139 | EXCEPTION_PROLOG_2 | |
140 | ||
92625d49 LC |
141 | #define EXCEPTION_PROLOG_0 \ |
142 | mtspr SPRN_SPRG_SCRATCH0,r10; \ | |
d5fd9d7d | 143 | mtspr SPRN_SPRG_SCRATCH1,r11 |
92625d49 | 144 | |
14cf11af PM |
145 | #define EXCEPTION_PROLOG_1 \ |
146 | mfspr r11,SPRN_SRR1; /* check whether user or kernel */ \ | |
147 | andi. r11,r11,MSR_PR; \ | |
148 | tophys(r11,r1); /* use tophys(r1) if kernel */ \ | |
149 | beq 1f; \ | |
ee43eb78 | 150 | mfspr r11,SPRN_SPRG_THREAD; \ |
14cf11af PM |
151 | lwz r11,THREAD_INFO-THREAD(r11); \ |
152 | addi r11,r11,THREAD_SIZE; \ | |
153 | tophys(r11,r11); \ | |
154 | 1: subi r11,r11,INT_FRAME_SIZE /* alloc exc. frame */ | |
155 | ||
156 | ||
157 | #define EXCEPTION_PROLOG_2 \ | |
14cf11af PM |
158 | stw r10,_CCR(r11); /* save registers */ \ |
159 | stw r12,GPR12(r11); \ | |
160 | stw r9,GPR9(r11); \ | |
ee43eb78 | 161 | mfspr r10,SPRN_SPRG_SCRATCH0; \ |
14cf11af | 162 | stw r10,GPR10(r11); \ |
ee43eb78 | 163 | mfspr r12,SPRN_SPRG_SCRATCH1; \ |
14cf11af PM |
164 | stw r12,GPR11(r11); \ |
165 | mflr r10; \ | |
166 | stw r10,_LINK(r11); \ | |
167 | mfspr r12,SPRN_SRR0; \ | |
168 | mfspr r9,SPRN_SRR1; \ | |
169 | stw r1,GPR1(r11); \ | |
170 | stw r1,0(r11); \ | |
171 | tovirt(r1,r11); /* set new kernel sp */ \ | |
172 | li r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \ | |
173 | MTMSRD(r10); /* (except for mach check in rtas) */ \ | |
174 | stw r0,GPR0(r11); \ | |
175 | SAVE_4GPRS(3, r11); \ | |
176 | SAVE_2GPRS(7, r11) | |
177 | ||
92625d49 LC |
178 | /* |
179 | * Exception exit code. | |
180 | */ | |
181 | #define EXCEPTION_EPILOG_0 \ | |
92625d49 LC |
182 | mfspr r10,SPRN_SPRG_SCRATCH0; \ |
183 | mfspr r11,SPRN_SPRG_SCRATCH1 | |
184 | ||
14cf11af PM |
185 | /* |
186 | * Note: code which follows this uses cr0.eq (set if from kernel), | |
187 | * r11, r12 (SRR0), and r9 (SRR1). | |
188 | * | |
189 | * Note2: once we have set r1 we are in a position to take exceptions | |
190 | * again, and we could thus set MSR:RI at that point. | |
191 | */ | |
192 | ||
193 | /* | |
194 | * Exception vectors. | |
195 | */ | |
196 | #define EXCEPTION(n, label, hdlr, xfer) \ | |
197 | . = n; \ | |
198 | label: \ | |
199 | EXCEPTION_PROLOG; \ | |
200 | addi r3,r1,STACK_FRAME_OVERHEAD; \ | |
201 | xfer(n, hdlr) | |
202 | ||
203 | #define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret) \ | |
204 | li r10,trap; \ | |
d73e0c99 | 205 | stw r10,_TRAP(r11); \ |
14cf11af PM |
206 | li r10,MSR_KERNEL; \ |
207 | copyee(r10, r9); \ | |
208 | bl tfer; \ | |
209 | i##n: \ | |
210 | .long hdlr; \ | |
211 | .long ret | |
212 | ||
213 | #define COPY_EE(d, s) rlwimi d,s,0,16,16 | |
214 | #define NOCOPY(d, s) | |
215 | ||
216 | #define EXC_XFER_STD(n, hdlr) \ | |
217 | EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full, \ | |
218 | ret_from_except_full) | |
219 | ||
220 | #define EXC_XFER_LITE(n, hdlr) \ | |
221 | EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \ | |
222 | ret_from_except) | |
223 | ||
224 | #define EXC_XFER_EE(n, hdlr) \ | |
225 | EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \ | |
226 | ret_from_except_full) | |
227 | ||
228 | #define EXC_XFER_EE_LITE(n, hdlr) \ | |
229 | EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \ | |
230 | ret_from_except) | |
231 | ||
232 | /* System reset */ | |
f307939f | 233 | EXCEPTION(0x100, Reset, system_reset_exception, EXC_XFER_STD) |
14cf11af PM |
234 | |
235 | /* Machine check */ | |
236 | . = 0x200 | |
237 | MachineCheck: | |
238 | EXCEPTION_PROLOG | |
239 | mfspr r4,SPRN_DAR | |
240 | stw r4,_DAR(r11) | |
ac21951f | 241 | li r5,RPN_PATTERN |
60e071fe | 242 | mtspr SPRN_DAR,r5 /* Tag DAR, to be used in DTLB Error */ |
14cf11af PM |
243 | mfspr r5,SPRN_DSISR |
244 | stw r5,_DSISR(r11) | |
245 | addi r3,r1,STACK_FRAME_OVERHEAD | |
dc1c1ca3 | 246 | EXC_XFER_STD(0x200, machine_check_exception) |
14cf11af PM |
247 | |
248 | /* Data access exception. | |
749137a2 | 249 | * This is "never generated" by the MPC8xx. |
14cf11af PM |
250 | */ |
251 | . = 0x300 | |
252 | DataAccess: | |
14cf11af PM |
253 | |
254 | /* Instruction access exception. | |
7439b37e | 255 | * This is "never generated" by the MPC8xx. |
14cf11af PM |
256 | */ |
257 | . = 0x400 | |
258 | InstructionAccess: | |
14cf11af PM |
259 | |
260 | /* External interrupt */ | |
261 | EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE) | |
262 | ||
263 | /* Alignment exception */ | |
264 | . = 0x600 | |
265 | Alignment: | |
266 | EXCEPTION_PROLOG | |
267 | mfspr r4,SPRN_DAR | |
268 | stw r4,_DAR(r11) | |
ac21951f | 269 | li r5,RPN_PATTERN |
60e071fe | 270 | mtspr SPRN_DAR,r5 /* Tag DAR, to be used in DTLB Error */ |
14cf11af PM |
271 | mfspr r5,SPRN_DSISR |
272 | stw r5,_DSISR(r11) | |
273 | addi r3,r1,STACK_FRAME_OVERHEAD | |
dc1c1ca3 | 274 | EXC_XFER_EE(0x600, alignment_exception) |
14cf11af PM |
275 | |
276 | /* Program check exception */ | |
dc1c1ca3 | 277 | EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD) |
14cf11af PM |
278 | |
279 | /* No FPU on MPC8xx. This exception is not supposed to happen. | |
280 | */ | |
dc1c1ca3 | 281 | EXCEPTION(0x800, FPUnavailable, unknown_exception, EXC_XFER_STD) |
14cf11af PM |
282 | |
283 | /* Decrementer */ | |
284 | EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE) | |
285 | ||
dc1c1ca3 SR |
286 | EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_EE) |
287 | EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
288 | |
289 | /* System call */ | |
290 | . = 0xc00 | |
291 | SystemCall: | |
292 | EXCEPTION_PROLOG | |
293 | EXC_XFER_EE_LITE(0xc00, DoSyscall) | |
294 | ||
295 | /* Single step - not used on 601 */ | |
dc1c1ca3 SR |
296 | EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD) |
297 | EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_EE) | |
298 | EXCEPTION(0xf00, Trap_0f, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
299 | |
300 | /* On the MPC8xx, this is a software emulation interrupt. It occurs | |
301 | * for all unimplemented and illegal instructions. | |
302 | */ | |
303 | EXCEPTION(0x1000, SoftEmu, SoftwareEmulation, EXC_XFER_STD) | |
304 | ||
305 | . = 0x1100 | |
306 | /* | |
307 | * For the MPC8xx, this is a software tablewalk to load the instruction | |
cbc130f1 LC |
308 | * TLB. The task switch loads the M_TW register with the pointer to the first |
309 | * level table. | |
14cf11af PM |
310 | * If we discover there is no second level table (value is zero) or if there |
311 | * is an invalid pte, we load that into the TLB, which causes another fault | |
312 | * into the TLB Error interrupt where we can handle such problems. | |
313 | * We have to use the MD_xxx registers for the tablewalk because the | |
314 | * equivalent MI_xxx registers only perform the attribute functions. | |
315 | */ | |
90883a82 LC |
316 | |
317 | #ifdef CONFIG_8xx_CPU15 | |
318 | #define INVALIDATE_ADJACENT_PAGES_CPU15(tmp, addr) \ | |
319 | addi tmp, addr, PAGE_SIZE; \ | |
320 | tlbie tmp; \ | |
321 | addi tmp, addr, -PAGE_SIZE; \ | |
322 | tlbie tmp | |
323 | #else | |
324 | #define INVALIDATE_ADJACENT_PAGES_CPU15(tmp, addr) | |
325 | #endif | |
326 | ||
14cf11af | 327 | InstructionTLBMiss: |
4b914286 | 328 | #if defined(CONFIG_8xx_CPU6) || defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC) || defined (CONFIG_HUGETLB_PAGE) |
b821c5fe | 329 | mtspr SPRN_SPRG_SCRATCH2, r3 |
14cf11af | 330 | #endif |
92625d49 | 331 | EXCEPTION_PROLOG_0 |
14cf11af PM |
332 | |
333 | /* If we are faulting a kernel address, we have to use the | |
334 | * kernel page tables. | |
335 | */ | |
d1b9f814 CL |
336 | mfspr r10, SPRN_SRR0 /* Get effective address of fault */ |
337 | INVALIDATE_ADJACENT_PAGES_CPU15(r11, r10) | |
4afb0be7 JT |
338 | /* Only modules will cause ITLB Misses as we always |
339 | * pin the first 8MB of kernel memory */ | |
4b914286 | 340 | #if defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC) || defined (CONFIG_HUGETLB_PAGE) |
d1b9f814 | 341 | mfcr r3 |
4b914286 CL |
342 | #endif |
343 | #if defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC) | |
d1b9f814 CL |
344 | IS_KERNEL(r11, r10) |
345 | #endif | |
fde5a905 | 346 | mfspr r11, SPRN_M_TW /* Get level 1 table */ |
d1b9f814 | 347 | #if defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC) |
eeba1f7c | 348 | BRANCH_UNLESS_KERNEL(3f) |
fde5a905 | 349 | lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha |
14cf11af | 350 | 3: |
4afb0be7 | 351 | #endif |
17bb312f LC |
352 | /* Insert level 1 index */ |
353 | rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 | |
fde5a905 | 354 | lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ |
14cf11af | 355 | |
d1406803 | 356 | /* Extract level 2 index */ |
17bb312f | 357 | rlwinm r10, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 |
4b914286 CL |
358 | #ifdef CONFIG_HUGETLB_PAGE |
359 | mtcr r11 | |
360 | bt- 28, 10f /* bit 28 = Large page (8M) */ | |
361 | bt- 29, 20f /* bit 29 = Large page (8M or 512k) */ | |
362 | #endif | |
e0a8e0d9 LC |
363 | rlwimi r10, r11, 0, 0, 32 - PAGE_SHIFT - 1 /* Add level 2 base */ |
364 | lwz r10, 0(r10) /* Get the pte */ | |
4b914286 CL |
365 | 4: |
366 | #if defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC) || defined (CONFIG_HUGETLB_PAGE) | |
367 | mtcr r3 | |
368 | #endif | |
e0a8e0d9 | 369 | /* Insert the APG into the TWC from the Linux PTE. */ |
5b2753fc | 370 | rlwimi r11, r10, 0, 25, 26 |
e0a8e0d9 LC |
371 | /* Load the MI_TWC with the attributes for this "segment." */ |
372 | MTSPR_CPU6(SPRN_MI_TWC, r11, r3) /* Set segment attributes */ | |
14cf11af | 373 | |
4b914286 CL |
374 | #if defined (CONFIG_HUGETLB_PAGE) && defined (CONFIG_PPC_4K_PAGES) |
375 | rlwimi r10, r11, 1, MI_SPS16K | |
376 | #endif | |
d069cb43 | 377 | #ifdef CONFIG_SWAP |
5ddb75ce LC |
378 | rlwinm r11, r10, 32-5, _PAGE_PRESENT |
379 | and r11, r11, r10 | |
380 | rlwimi r10, r11, 0, _PAGE_PRESENT | |
d069cb43 | 381 | #endif |
5ddb75ce | 382 | li r11, RPN_PATTERN |
14cf11af | 383 | /* The Linux PTE won't go exactly into the MMU TLB. |
e0a8e0d9 | 384 | * Software indicator bits 20-23 and 28 must be clear. |
14cf11af PM |
385 | * Software indicator bits 24, 25, 26, and 27 must be |
386 | * set. All other Linux PTE bits control the behavior | |
387 | * of the MMU. | |
388 | */ | |
4b914286 CL |
389 | #if defined (CONFIG_HUGETLB_PAGE) && defined (CONFIG_PPC_4K_PAGES) |
390 | rlwimi r10, r11, 0, 0x0ff0 /* Set 24-27, clear 20-23 */ | |
391 | #else | |
e0a8e0d9 | 392 | rlwimi r10, r11, 0, 0x0ff8 /* Set 24-27, clear 20-23,28 */ |
4b914286 | 393 | #endif |
d3e40262 | 394 | MTSPR_CPU6(SPRN_MI_RPN, r10, r3) /* Update TLB entry */ |
14cf11af | 395 | |
469d62be | 396 | /* Restore registers */ |
4b914286 | 397 | #if defined(CONFIG_8xx_CPU6) || defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC) || defined (CONFIG_HUGETLB_PAGE) |
b821c5fe | 398 | mfspr r3, SPRN_SPRG_SCRATCH2 |
14cf11af | 399 | #endif |
92625d49 | 400 | EXCEPTION_EPILOG_0 |
14cf11af PM |
401 | rfi |
402 | ||
4b914286 CL |
403 | #ifdef CONFIG_HUGETLB_PAGE |
404 | 10: /* 8M pages */ | |
405 | #ifdef CONFIG_PPC_16K_PAGES | |
406 | /* Extract level 2 index */ | |
407 | rlwinm r10, r10, 32 - (PAGE_SHIFT_8M - PAGE_SHIFT), 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1), 29 | |
408 | /* Add level 2 base */ | |
409 | rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1) - 1 | |
410 | #else | |
411 | /* Level 2 base */ | |
412 | rlwinm r10, r11, 0, ~HUGEPD_SHIFT_MASK | |
413 | #endif | |
414 | lwz r10, 0(r10) /* Get the pte */ | |
415 | rlwinm r11, r11, 0, 0xf | |
416 | b 4b | |
417 | ||
418 | 20: /* 512k pages */ | |
419 | /* Extract level 2 index */ | |
420 | rlwinm r10, r10, 32 - (PAGE_SHIFT_512K - PAGE_SHIFT), 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1), 29 | |
421 | /* Add level 2 base */ | |
422 | rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1) - 1 | |
423 | lwz r10, 0(r10) /* Get the pte */ | |
424 | rlwinm r11, r11, 0, 0xf | |
425 | b 4b | |
426 | #endif | |
427 | ||
14cf11af PM |
428 | . = 0x1200 |
429 | DataStoreTLBMiss: | |
36eb1542 | 430 | mtspr SPRN_SPRG_SCRATCH2, r3 |
92625d49 | 431 | EXCEPTION_PROLOG_0 |
36eb1542 | 432 | mfcr r3 |
14cf11af PM |
433 | |
434 | /* If we are faulting a kernel address, we have to use the | |
435 | * kernel page tables. | |
436 | */ | |
36eb1542 CL |
437 | mfspr r10, SPRN_MD_EPN |
438 | rlwinm r10, r10, 16, 0xfff8 | |
439 | cmpli cr0, r10, PAGE_OFFSET@h | |
440 | mfspr r11, SPRN_M_TW /* Get level 1 table */ | |
441 | blt+ 3f | |
62f64b49 | 442 | #ifndef CONFIG_PIN_TLB_IMMR |
36eb1542 | 443 | cmpli cr0, r10, VIRT_IMMR_BASE@h |
bb7f3808 | 444 | #endif |
36eb1542 CL |
445 | _ENTRY(DTLBMiss_cmp) |
446 | cmpli cr7, r10, (PAGE_OFFSET + 0x1800000)@h | |
447 | lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha | |
62f64b49 | 448 | #ifndef CONFIG_PIN_TLB_IMMR |
4badd43a CL |
449 | _ENTRY(DTLBMiss_jmp) |
450 | beq- DTLBMissIMMR | |
451 | #endif | |
36eb1542 | 452 | blt cr7, DTLBMissLinear |
14cf11af | 453 | 3: |
bb7f3808 | 454 | mfspr r10, SPRN_MD_EPN |
2eb2fd95 | 455 | |
17bb312f LC |
456 | /* Insert level 1 index */ |
457 | rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 | |
fde5a905 | 458 | lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ |
14cf11af PM |
459 | |
460 | /* We have a pte table, so load fetch the pte from the table. | |
461 | */ | |
33fb845a | 462 | /* Extract level 2 index */ |
d1406803 | 463 | rlwinm r10, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 |
4b914286 CL |
464 | #ifdef CONFIG_HUGETLB_PAGE |
465 | mtcr r11 | |
466 | bt- 28, 10f /* bit 28 = Large page (8M) */ | |
467 | bt- 29, 20f /* bit 29 = Large page (8M or 512k) */ | |
468 | #endif | |
d1406803 | 469 | rlwimi r10, r11, 0, 0, 32 - PAGE_SHIFT - 1 /* Add level 2 base */ |
14cf11af | 470 | lwz r10, 0(r10) /* Get the pte */ |
4b914286 CL |
471 | 4: |
472 | mtcr r3 | |
14cf11af | 473 | |
e0a8e0d9 LC |
474 | /* Insert the Guarded flag and APG into the TWC from the Linux PTE. |
475 | * It is bit 26-27 of both the Linux PTE and the TWC (at least | |
14cf11af PM |
476 | * I got that right :-). It will be better when we can put |
477 | * this into the Linux pgd/pmd and load it in the operation | |
478 | * above. | |
479 | */ | |
e0a8e0d9 | 480 | rlwimi r11, r10, 0, 26, 27 |
0c466169 JT |
481 | /* Insert the WriteThru flag into the TWC from the Linux PTE. |
482 | * It is bit 25 in the Linux PTE and bit 30 in the TWC | |
483 | */ | |
484 | rlwimi r11, r10, 32-5, 30, 30 | |
d3e40262 | 485 | MTSPR_CPU6(SPRN_MD_TWC, r11, r3) |
14cf11af | 486 | |
4b914286 CL |
487 | /* In 4k pages mode, SPS (bit 28) in RPN must match PS[1] (bit 29) |
488 | * In 16k pages mode, SPS is always 1 */ | |
489 | #if defined (CONFIG_HUGETLB_PAGE) && defined (CONFIG_PPC_4K_PAGES) | |
490 | rlwimi r10, r11, 1, MD_SPS16K | |
491 | #endif | |
fe11dc3f JT |
492 | /* Both _PAGE_ACCESSED and _PAGE_PRESENT has to be set. |
493 | * We also need to know if the insn is a load/store, so: | |
494 | * Clear _PAGE_PRESENT and load that which will | |
495 | * trap into DTLB Error with store bit set accordinly. | |
496 | */ | |
497 | /* PRESENT=0x1, ACCESSED=0x20 | |
498 | * r11 = ((r10 & PRESENT) & ((r10 & ACCESSED) >> 5)); | |
499 | * r10 = (r10 & ~PRESENT) | r11; | |
500 | */ | |
d069cb43 | 501 | #ifdef CONFIG_SWAP |
990d89c6 | 502 | rlwinm r11, r10, 32-5, _PAGE_PRESENT |
fe11dc3f | 503 | and r11, r11, r10 |
990d89c6 | 504 | rlwimi r10, r11, 0, _PAGE_PRESENT |
d069cb43 | 505 | #endif |
14cf11af | 506 | /* The Linux PTE won't go exactly into the MMU TLB. |
fe11dc3f | 507 | * Software indicator bits 22 and 28 must be clear. |
14cf11af PM |
508 | * Software indicator bits 24, 25, 26, and 27 must be |
509 | * set. All other Linux PTE bits control the behavior | |
510 | * of the MMU. | |
511 | */ | |
5ddb75ce | 512 | li r11, RPN_PATTERN |
4b914286 CL |
513 | #if defined (CONFIG_HUGETLB_PAGE) && defined (CONFIG_PPC_4K_PAGES) |
514 | rlwimi r10, r11, 0, 24, 27 /* Set 24-27 */ | |
515 | #else | |
14cf11af | 516 | rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */ |
4b914286 | 517 | #endif |
5b2753fc | 518 | rlwimi r10, r11, 0, 20, 20 /* clear 20 */ |
d3e40262 | 519 | MTSPR_CPU6(SPRN_MD_RPN, r10, r3) /* Update TLB entry */ |
14cf11af | 520 | |
469d62be | 521 | /* Restore registers */ |
b821c5fe | 522 | mfspr r3, SPRN_SPRG_SCRATCH2 |
92625d49 | 523 | mtspr SPRN_DAR, r11 /* Tag DAR */ |
92625d49 | 524 | EXCEPTION_EPILOG_0 |
14cf11af PM |
525 | rfi |
526 | ||
4b914286 CL |
527 | #ifdef CONFIG_HUGETLB_PAGE |
528 | 10: /* 8M pages */ | |
529 | /* Extract level 2 index */ | |
530 | #ifdef CONFIG_PPC_16K_PAGES | |
531 | rlwinm r10, r10, 32 - (PAGE_SHIFT_8M - PAGE_SHIFT), 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1), 29 | |
532 | /* Add level 2 base */ | |
533 | rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1) - 1 | |
534 | #else | |
535 | /* Level 2 base */ | |
536 | rlwinm r10, r11, 0, ~HUGEPD_SHIFT_MASK | |
537 | #endif | |
538 | lwz r10, 0(r10) /* Get the pte */ | |
539 | rlwinm r11, r11, 0, 0xf | |
540 | b 4b | |
541 | ||
542 | 20: /* 512k pages */ | |
543 | /* Extract level 2 index */ | |
544 | rlwinm r10, r10, 32 - (PAGE_SHIFT_512K - PAGE_SHIFT), 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1), 29 | |
545 | /* Add level 2 base */ | |
546 | rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1) - 1 | |
547 | lwz r10, 0(r10) /* Get the pte */ | |
548 | rlwinm r11, r11, 0, 0xf | |
549 | b 4b | |
550 | #endif | |
a372acfa | 551 | |
14cf11af PM |
552 | /* This is an instruction TLB error on the MPC8xx. This could be due |
553 | * to many reasons, such as executing guarded memory or illegal instruction | |
554 | * addresses. There is nothing to do but handle a big time error fault. | |
555 | */ | |
556 | . = 0x1300 | |
557 | InstructionTLBError: | |
5ddb75ce | 558 | EXCEPTION_PROLOG |
7439b37e LC |
559 | mr r4,r12 |
560 | mr r5,r9 | |
c51a6821 LC |
561 | andis. r10,r5,0x4000 |
562 | beq+ 1f | |
563 | tlbie r4 | |
7439b37e | 564 | /* 0x400 is InstructionAccess exception, needed by bad_page_fault() */ |
c51a6821 | 565 | 1: EXC_XFER_LITE(0x400, handle_page_fault) |
14cf11af PM |
566 | |
567 | /* This is the data TLB error on the MPC8xx. This could be due to | |
140a6a60 LC |
568 | * many reasons, including a dirty update to a pte. We bail out to |
569 | * a higher level function that can handle it. | |
14cf11af PM |
570 | */ |
571 | . = 0x1400 | |
572 | DataTLBError: | |
92625d49 | 573 | EXCEPTION_PROLOG_0 |
d5fd9d7d | 574 | mfcr r10 |
14cf11af | 575 | |
5bcbe24f | 576 | mfspr r11, SPRN_DAR |
ac21951f | 577 | cmpwi cr0, r11, RPN_PATTERN |
0a2ab51f | 578 | beq- FixupDAR /* must be a buggy dcbX, icbi insn. */ |
3e436403 | 579 | DARFixed:/* Return from dcbx instruction bug workaround */ |
6cde2b6f LC |
580 | EXCEPTION_PROLOG_1 |
581 | EXCEPTION_PROLOG_2 | |
c51a6821 LC |
582 | mfspr r5,SPRN_DSISR |
583 | stw r5,_DSISR(r11) | |
749137a2 | 584 | mfspr r4,SPRN_DAR |
c51a6821 LC |
585 | andis. r10,r5,0x4000 |
586 | beq+ 1f | |
587 | tlbie r4 | |
588 | 1: li r10,RPN_PATTERN | |
749137a2 LC |
589 | mtspr SPRN_DAR,r10 /* Tag DAR, to be used in DTLB Error */ |
590 | /* 0x300 is DataAccess exception, needed by bad_page_fault() */ | |
591 | EXC_XFER_LITE(0x300, handle_page_fault) | |
14cf11af | 592 | |
dc1c1ca3 SR |
593 | EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE) |
594 | EXCEPTION(0x1600, Trap_16, unknown_exception, EXC_XFER_EE) | |
595 | EXCEPTION(0x1700, Trap_17, unknown_exception, EXC_XFER_EE) | |
596 | EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE) | |
597 | EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE) | |
598 | EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_EE) | |
599 | EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
600 | |
601 | /* On the MPC8xx, these next four traps are used for development | |
602 | * support of breakpoints and such. Someday I will get around to | |
603 | * using them. | |
604 | */ | |
dc1c1ca3 SR |
605 | EXCEPTION(0x1c00, Trap_1c, unknown_exception, EXC_XFER_EE) |
606 | EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_EE) | |
607 | EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_EE) | |
608 | EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_EE) | |
14cf11af PM |
609 | |
610 | . = 0x2000 | |
611 | ||
73a53206 CL |
612 | /* |
613 | * Bottom part of DataStoreTLBMiss handlers for IMMR area and linear RAM. | |
614 | * not enough space in the DataStoreTLBMiss area. | |
615 | */ | |
616 | DTLBMissIMMR: | |
36eb1542 | 617 | mtcr r3 |
73a53206 CL |
618 | /* Set 512k byte guarded page and mark it valid */ |
619 | li r10, MD_PS512K | MD_GUARDED | MD_SVALID | |
620 | MTSPR_CPU6(SPRN_MD_TWC, r10, r11) | |
621 | mfspr r10, SPRN_IMMR /* Get current IMMR */ | |
622 | rlwinm r10, r10, 0, 0xfff80000 /* Get 512 kbytes boundary */ | |
623 | ori r10, r10, 0xf0 | MD_SPS16K | _PAGE_SHARED | _PAGE_DIRTY | \ | |
624 | _PAGE_PRESENT | _PAGE_NO_CACHE | |
625 | MTSPR_CPU6(SPRN_MD_RPN, r10, r11) /* Update TLB entry */ | |
626 | ||
627 | li r11, RPN_PATTERN | |
628 | mtspr SPRN_DAR, r11 /* Tag DAR */ | |
36eb1542 | 629 | mfspr r3, SPRN_SPRG_SCRATCH2 |
73a53206 CL |
630 | EXCEPTION_EPILOG_0 |
631 | rfi | |
632 | ||
633 | DTLBMissLinear: | |
36eb1542 | 634 | mtcr r3 |
73a53206 | 635 | /* Set 8M byte page and mark it valid */ |
36eb1542 CL |
636 | li r11, MD_PS8MEG | MD_SVALID |
637 | MTSPR_CPU6(SPRN_MD_TWC, r11, r3) | |
638 | rlwinm r10, r10, 16, 0x0f800000 /* 8xx supports max 256Mb RAM */ | |
73a53206 CL |
639 | ori r10, r10, 0xf0 | MD_SPS16K | _PAGE_SHARED | _PAGE_DIRTY | \ |
640 | _PAGE_PRESENT | |
641 | MTSPR_CPU6(SPRN_MD_RPN, r10, r11) /* Update TLB entry */ | |
642 | ||
643 | li r11, RPN_PATTERN | |
644 | mtspr SPRN_DAR, r11 /* Tag DAR */ | |
36eb1542 | 645 | mfspr r3, SPRN_SPRG_SCRATCH2 |
73a53206 CL |
646 | EXCEPTION_EPILOG_0 |
647 | rfi | |
648 | ||
0a2ab51f JT |
649 | /* This is the procedure to calculate the data EA for buggy dcbx,dcbi instructions |
650 | * by decoding the registers used by the dcbx instruction and adding them. | |
3e436403 | 651 | * DAR is set to the calculated address. |
0a2ab51f JT |
652 | */ |
653 | /* define if you don't want to use self modifying code */ | |
654 | #define NO_SELF_MODIFYING_CODE | |
655 | FixupDAR:/* Entry point for dcbx workaround. */ | |
5bcbe24f | 656 | mtspr SPRN_SPRG_SCRATCH2, r10 |
0a2ab51f JT |
657 | /* fetch instruction from memory. */ |
658 | mfspr r10, SPRN_SRR0 | |
eeba1f7c | 659 | IS_KERNEL(r11, r10) |
fde5a905 | 660 | mfspr r11, SPRN_M_TW /* Get level 1 table */ |
eeba1f7c | 661 | BRANCH_UNLESS_KERNEL(3f) |
bb7f3808 CL |
662 | rlwinm r11, r10, 16, 0xfff8 |
663 | _ENTRY(FixupDAR_cmp) | |
4ad27450 | 664 | cmpli cr7, r11, (PAGE_OFFSET + 0x1800000)@h |
36eb1542 CL |
665 | /* create physical page address from effective address */ |
666 | tophys(r11, r10) | |
667 | blt- cr7, 201f | |
fde5a905 | 668 | lis r11, (swapper_pg_dir-PAGE_OFFSET)@ha |
17bb312f LC |
669 | /* Insert level 1 index */ |
670 | 3: rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 | |
fde5a905 | 671 | lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ |
4b914286 CL |
672 | mtcr r11 |
673 | bt 28,200f /* bit 28 = Large page (8M) */ | |
674 | bt 29,202f /* bit 29 = Large page (8M or 512K) */ | |
17bb312f LC |
675 | rlwinm r11, r11,0,0,19 /* Extract page descriptor page address */ |
676 | /* Insert level 2 index */ | |
677 | rlwimi r11, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 | |
678 | lwz r11, 0(r11) /* Get the pte */ | |
0a2ab51f | 679 | /* concat physical page address(r11) and page offset(r10) */ |
d1406803 | 680 | rlwimi r11, r10, 0, 32 - PAGE_SHIFT, 31 |
a372acfa | 681 | 201: lwz r11,0(r11) |
0a2ab51f JT |
682 | /* Check if it really is a dcbx instruction. */ |
683 | /* dcbt and dcbtst does not generate DTLB Misses/Errors, | |
684 | * no need to include them here */ | |
41cacac6 LC |
685 | xoris r10, r11, 0x7c00 /* check if major OP code is 31 */ |
686 | rlwinm r10, r10, 0, 21, 5 | |
0a2ab51f JT |
687 | cmpwi cr0, r10, 2028 /* Is dcbz? */ |
688 | beq+ 142f | |
689 | cmpwi cr0, r10, 940 /* Is dcbi? */ | |
690 | beq+ 142f | |
691 | cmpwi cr0, r10, 108 /* Is dcbst? */ | |
692 | beq+ 144f /* Fix up store bit! */ | |
693 | cmpwi cr0, r10, 172 /* Is dcbf? */ | |
694 | beq+ 142f | |
695 | cmpwi cr0, r10, 1964 /* Is icbi? */ | |
696 | beq+ 142f | |
5bcbe24f LC |
697 | 141: mfspr r10,SPRN_SPRG_SCRATCH2 |
698 | b DARFixed /* Nope, go back to normal TLB processing */ | |
0a2ab51f | 699 | |
4b914286 CL |
700 | /* concat physical page address(r11) and page offset(r10) */ |
701 | 200: | |
702 | #ifdef CONFIG_PPC_16K_PAGES | |
703 | rlwinm r11, r11, 0, 0, 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1) - 1 | |
704 | rlwimi r11, r10, 32 - (PAGE_SHIFT_8M - 2), 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1), 29 | |
705 | #else | |
706 | rlwinm r11, r10, 0, ~HUGEPD_SHIFT_MASK | |
707 | #endif | |
708 | lwz r11, 0(r11) /* Get the pte */ | |
709 | /* concat physical page address(r11) and page offset(r10) */ | |
710 | rlwimi r11, r10, 0, 32 - PAGE_SHIFT_8M, 31 | |
711 | b 201b | |
712 | ||
713 | 202: | |
714 | rlwinm r11, r11, 0, 0, 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1) - 1 | |
715 | rlwimi r11, r10, 32 - (PAGE_SHIFT_512K - 2), 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1), 29 | |
716 | lwz r11, 0(r11) /* Get the pte */ | |
717 | /* concat physical page address(r11) and page offset(r10) */ | |
718 | rlwimi r11, r10, 0, 32 - PAGE_SHIFT_512K, 31 | |
719 | b 201b | |
720 | ||
0a2ab51f JT |
721 | 144: mfspr r10, SPRN_DSISR |
722 | rlwinm r10, r10,0,7,5 /* Clear store bit for buggy dcbst insn */ | |
723 | mtspr SPRN_DSISR, r10 | |
724 | 142: /* continue, it was a dcbx, dcbi instruction. */ | |
0a2ab51f JT |
725 | #ifndef NO_SELF_MODIFYING_CODE |
726 | andis. r10,r11,0x1f /* test if reg RA is r0 */ | |
727 | li r10,modified_instr@l | |
728 | dcbtst r0,r10 /* touch for store */ | |
729 | rlwinm r11,r11,0,0,20 /* Zero lower 10 bits */ | |
730 | oris r11,r11,640 /* Transform instr. to a "add r10,RA,RB" */ | |
731 | ori r11,r11,532 | |
732 | stw r11,0(r10) /* store add/and instruction */ | |
733 | dcbf 0,r10 /* flush new instr. to memory. */ | |
734 | icbi 0,r10 /* invalidate instr. cache line */ | |
92625d49 LC |
735 | mfspr r11, SPRN_SPRG_SCRATCH1 /* restore r11 */ |
736 | mfspr r10, SPRN_SPRG_SCRATCH0 /* restore r10 */ | |
0a2ab51f JT |
737 | isync /* Wait until new instr is loaded from memory */ |
738 | modified_instr: | |
739 | .space 4 /* this is where the add instr. is stored */ | |
740 | bne+ 143f | |
741 | subf r10,r0,r10 /* r10=r10-r0, only if reg RA is r0 */ | |
742 | 143: mtdar r10 /* store faulting EA in DAR */ | |
5bcbe24f | 743 | mfspr r10,SPRN_SPRG_SCRATCH2 |
0a2ab51f JT |
744 | b DARFixed /* Go back to normal TLB handling */ |
745 | #else | |
746 | mfctr r10 | |
747 | mtdar r10 /* save ctr reg in DAR */ | |
748 | rlwinm r10, r11, 24, 24, 28 /* offset into jump table for reg RB */ | |
749 | addi r10, r10, 150f@l /* add start of table */ | |
750 | mtctr r10 /* load ctr with jump address */ | |
751 | xor r10, r10, r10 /* sum starts at zero */ | |
752 | bctr /* jump into table */ | |
753 | 150: | |
754 | add r10, r10, r0 ;b 151f | |
755 | add r10, r10, r1 ;b 151f | |
756 | add r10, r10, r2 ;b 151f | |
757 | add r10, r10, r3 ;b 151f | |
758 | add r10, r10, r4 ;b 151f | |
759 | add r10, r10, r5 ;b 151f | |
760 | add r10, r10, r6 ;b 151f | |
761 | add r10, r10, r7 ;b 151f | |
762 | add r10, r10, r8 ;b 151f | |
763 | add r10, r10, r9 ;b 151f | |
764 | mtctr r11 ;b 154f /* r10 needs special handling */ | |
765 | mtctr r11 ;b 153f /* r11 needs special handling */ | |
766 | add r10, r10, r12 ;b 151f | |
767 | add r10, r10, r13 ;b 151f | |
768 | add r10, r10, r14 ;b 151f | |
769 | add r10, r10, r15 ;b 151f | |
770 | add r10, r10, r16 ;b 151f | |
771 | add r10, r10, r17 ;b 151f | |
772 | add r10, r10, r18 ;b 151f | |
773 | add r10, r10, r19 ;b 151f | |
774 | add r10, r10, r20 ;b 151f | |
775 | add r10, r10, r21 ;b 151f | |
776 | add r10, r10, r22 ;b 151f | |
777 | add r10, r10, r23 ;b 151f | |
778 | add r10, r10, r24 ;b 151f | |
779 | add r10, r10, r25 ;b 151f | |
780 | add r10, r10, r26 ;b 151f | |
781 | add r10, r10, r27 ;b 151f | |
782 | add r10, r10, r28 ;b 151f | |
783 | add r10, r10, r29 ;b 151f | |
784 | add r10, r10, r30 ;b 151f | |
785 | add r10, r10, r31 | |
786 | 151: | |
787 | rlwinm. r11,r11,19,24,28 /* offset into jump table for reg RA */ | |
788 | beq 152f /* if reg RA is zero, don't add it */ | |
789 | addi r11, r11, 150b@l /* add start of table */ | |
790 | mtctr r11 /* load ctr with jump address */ | |
791 | rlwinm r11,r11,0,16,10 /* make sure we don't execute this more than once */ | |
792 | bctr /* jump into table */ | |
793 | 152: | |
794 | mfdar r11 | |
795 | mtctr r11 /* restore ctr reg from DAR */ | |
796 | mtdar r10 /* save fault EA to DAR */ | |
5bcbe24f | 797 | mfspr r10,SPRN_SPRG_SCRATCH2 |
0a2ab51f JT |
798 | b DARFixed /* Go back to normal TLB handling */ |
799 | ||
800 | /* special handling for r10,r11 since these are modified already */ | |
92625d49 | 801 | 153: mfspr r11, SPRN_SPRG_SCRATCH1 /* load r11 from SPRN_SPRG_SCRATCH1 */ |
111e32b2 LC |
802 | add r10, r10, r11 /* add it */ |
803 | mfctr r11 /* restore r11 */ | |
804 | b 151b | |
92625d49 | 805 | 154: mfspr r11, SPRN_SPRG_SCRATCH0 /* load r10 from SPRN_SPRG_SCRATCH0 */ |
111e32b2 | 806 | add r10, r10, r11 /* add it */ |
0a2ab51f JT |
807 | mfctr r11 /* restore r11 */ |
808 | b 151b | |
809 | #endif | |
810 | ||
14cf11af PM |
811 | /* |
812 | * This is where the main kernel code starts. | |
813 | */ | |
814 | start_here: | |
815 | /* ptr to current */ | |
816 | lis r2,init_task@h | |
817 | ori r2,r2,init_task@l | |
818 | ||
819 | /* ptr to phys current thread */ | |
820 | tophys(r4,r2) | |
821 | addi r4,r4,THREAD /* init task's THREAD */ | |
ee43eb78 | 822 | mtspr SPRN_SPRG_THREAD,r4 |
14cf11af PM |
823 | |
824 | /* stack */ | |
825 | lis r1,init_thread_union@ha | |
826 | addi r1,r1,init_thread_union@l | |
827 | li r0,0 | |
828 | stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1) | |
829 | ||
830 | bl early_init /* We have to do this with MMU on */ | |
831 | ||
832 | /* | |
833 | * Decide what sort of machine this is and initialize the MMU. | |
834 | */ | |
6dece0eb SW |
835 | li r3,0 |
836 | mr r4,r31 | |
14cf11af PM |
837 | bl machine_init |
838 | bl MMU_init | |
839 | ||
840 | /* | |
841 | * Go back to running unmapped so we can load up new values | |
842 | * and change to using our exception vectors. | |
843 | * On the 8xx, all we have to do is invalidate the TLB to clear | |
844 | * the old 8M byte TLB mappings and load the page table base register. | |
845 | */ | |
846 | /* The right way to do this would be to track it down through | |
847 | * init's THREAD like the context switch code does, but this is | |
848 | * easier......until someone changes init's static structures. | |
849 | */ | |
fde5a905 | 850 | lis r6, swapper_pg_dir@ha |
14cf11af PM |
851 | tophys(r6,r6) |
852 | #ifdef CONFIG_8xx_CPU6 | |
853 | lis r4, cpu6_errata_word@h | |
854 | ori r4, r4, cpu6_errata_word@l | |
cbc130f1 | 855 | li r3, 0x3f80 |
14cf11af PM |
856 | stw r3, 12(r4) |
857 | lwz r3, 12(r4) | |
858 | #endif | |
cbc130f1 | 859 | mtspr SPRN_M_TW, r6 |
14cf11af PM |
860 | lis r4,2f@h |
861 | ori r4,r4,2f@l | |
862 | tophys(r4,r4) | |
863 | li r3,MSR_KERNEL & ~(MSR_IR|MSR_DR) | |
864 | mtspr SPRN_SRR0,r4 | |
865 | mtspr SPRN_SRR1,r3 | |
866 | rfi | |
867 | /* Load up the kernel context */ | |
868 | 2: | |
869 | SYNC /* Force all PTE updates to finish */ | |
870 | tlbia /* Clear all TLB entries */ | |
871 | sync /* wait for tlbia/tlbie to finish */ | |
872 | TLBSYNC /* ... on all CPUs */ | |
873 | ||
874 | /* set up the PTE pointers for the Abatron bdiGDB. | |
875 | */ | |
876 | tovirt(r6,r6) | |
877 | lis r5, abatron_pteptrs@h | |
878 | ori r5, r5, abatron_pteptrs@l | |
879 | stw r5, 0xf0(r0) /* Must match your Abatron config file */ | |
880 | tophys(r5,r5) | |
881 | stw r6, 0(r5) | |
882 | ||
883 | /* Now turn on the MMU for real! */ | |
884 | li r4,MSR_KERNEL | |
885 | lis r3,start_kernel@h | |
886 | ori r3,r3,start_kernel@l | |
887 | mtspr SPRN_SRR0,r3 | |
888 | mtspr SPRN_SRR1,r4 | |
889 | rfi /* enable MMU and jump to start_kernel */ | |
890 | ||
891 | /* Set up the initial MMU state so we can do the first level of | |
892 | * kernel initialization. This maps the first 8 MBytes of memory 1:1 | |
893 | * virtual to physical. Also, set the cache mode since that is defined | |
894 | * by TLB entries and perform any additional mapping (like of the IMMR). | |
895 | * If configured to pin some TLBs, we pin the first 8 Mbytes of kernel, | |
f86ef74e | 896 | * 24 Mbytes of data, and the 512k IMMR space. Anything not covered by |
14cf11af PM |
897 | * these mappings is mapped by page tables. |
898 | */ | |
899 | initial_mmu: | |
6264dbb9 CL |
900 | li r8, 0 |
901 | mtspr SPRN_MI_CTR, r8 /* remove PINNED ITLB entries */ | |
902 | lis r10, MD_RESETVAL@h | |
903 | #ifndef CONFIG_8xx_COPYBACK | |
904 | oris r10, r10, MD_WTDEF@h | |
905 | #endif | |
906 | mtspr SPRN_MD_CTR, r10 /* remove PINNED DTLB entries */ | |
907 | ||
14cf11af | 908 | tlbia /* Invalidate all TLB entries */ |
9f4f04ba JT |
909 | /* Always pin the first 8 MB ITLB to prevent ITLB |
910 | misses while mucking around with SRR0/SRR1 in asm | |
911 | */ | |
14cf11af PM |
912 | lis r8, MI_RSV4I@h |
913 | ori r8, r8, 0x1c00 | |
9f4f04ba | 914 | |
14cf11af PM |
915 | mtspr SPRN_MI_CTR, r8 /* Set instruction MMU control */ |
916 | ||
917 | #ifdef CONFIG_PIN_TLB | |
6264dbb9 | 918 | oris r10, r10, MD_RSV4I@h |
14cf11af | 919 | mtspr SPRN_MD_CTR, r10 /* Set data TLB control */ |
6264dbb9 | 920 | #endif |
14cf11af | 921 | |
4ad27450 | 922 | /* Now map the lower 8 Meg into the ITLB. */ |
14cf11af PM |
923 | lis r8, KERNELBASE@h /* Create vaddr for TLB */ |
924 | ori r8, r8, MI_EVALID /* Mark it valid */ | |
925 | mtspr SPRN_MI_EPN, r8 | |
5b2753fc | 926 | li r8, MI_PS8MEG | (2 << 5) /* Set 8M byte page, APG 2 */ |
14cf11af PM |
927 | ori r8, r8, MI_SVALID /* Make it valid */ |
928 | mtspr SPRN_MI_TWC, r8 | |
14cf11af PM |
929 | li r8, MI_BOOTINIT /* Create RPN for address 0 */ |
930 | mtspr SPRN_MI_RPN, r8 /* Store TLB entry */ | |
4ad27450 | 931 | |
5b2753fc LC |
932 | lis r8, MI_APG_INIT@h /* Set protection modes */ |
933 | ori r8, r8, MI_APG_INIT@l | |
14cf11af | 934 | mtspr SPRN_MI_AP, r8 |
5b2753fc LC |
935 | lis r8, MD_APG_INIT@h |
936 | ori r8, r8, MD_APG_INIT@l | |
14cf11af PM |
937 | mtspr SPRN_MD_AP, r8 |
938 | ||
f86ef74e | 939 | /* Map a 512k page for the IMMR to get the processor |
14cf11af PM |
940 | * internal registers (among other things). |
941 | */ | |
62f64b49 CL |
942 | #ifdef CONFIG_PIN_TLB_IMMR |
943 | ori r10, r10, 0x1c00 | |
944 | mtspr SPRN_MD_CTR, r10 | |
945 | ||
14cf11af | 946 | mfspr r9, 638 /* Get current IMMR */ |
f86ef74e | 947 | andis. r9, r9, 0xfff8 /* Get 512 kbytes boundary */ |
14cf11af | 948 | |
f86ef74e | 949 | lis r8, VIRT_IMMR_BASE@h /* Create vaddr for TLB */ |
14cf11af PM |
950 | ori r8, r8, MD_EVALID /* Mark it valid */ |
951 | mtspr SPRN_MD_EPN, r8 | |
f86ef74e | 952 | li r8, MD_PS512K | MD_GUARDED /* Set 512k byte page */ |
14cf11af PM |
953 | ori r8, r8, MD_SVALID /* Make it valid */ |
954 | mtspr SPRN_MD_TWC, r8 | |
955 | mr r8, r9 /* Create paddr for TLB */ | |
956 | ori r8, r8, MI_BOOTINIT|0x2 /* Inhibit cache -- Cort */ | |
957 | mtspr SPRN_MD_RPN, r8 | |
14cf11af PM |
958 | #endif |
959 | ||
960 | /* Since the cache is enabled according to the information we | |
961 | * just loaded into the TLB, invalidate and enable the caches here. | |
962 | * We should probably check/set other modes....later. | |
963 | */ | |
964 | lis r8, IDC_INVALL@h | |
965 | mtspr SPRN_IC_CST, r8 | |
966 | mtspr SPRN_DC_CST, r8 | |
967 | lis r8, IDC_ENABLE@h | |
968 | mtspr SPRN_IC_CST, r8 | |
969 | #ifdef CONFIG_8xx_COPYBACK | |
970 | mtspr SPRN_DC_CST, r8 | |
971 | #else | |
972 | /* For a debug option, I left this here to easily enable | |
973 | * the write through cache mode | |
974 | */ | |
975 | lis r8, DC_SFWT@h | |
976 | mtspr SPRN_DC_CST, r8 | |
977 | lis r8, IDC_ENABLE@h | |
978 | mtspr SPRN_DC_CST, r8 | |
979 | #endif | |
980 | blr | |
981 | ||
982 | ||
14cf11af PM |
983 | /* |
984 | * We put a few things here that have to be page-aligned. | |
985 | * This stuff goes at the beginning of the data segment, | |
986 | * which is page-aligned. | |
987 | */ | |
988 | .data | |
989 | .globl sdata | |
990 | sdata: | |
991 | .globl empty_zero_page | |
d1406803 | 992 | .align PAGE_SHIFT |
14cf11af | 993 | empty_zero_page: |
d1406803 | 994 | .space PAGE_SIZE |
9445aa1a | 995 | EXPORT_SYMBOL(empty_zero_page) |
14cf11af PM |
996 | |
997 | .globl swapper_pg_dir | |
998 | swapper_pg_dir: | |
d1406803 | 999 | .space PGD_TABLE_SIZE |
14cf11af | 1000 | |
14cf11af PM |
1001 | /* Room for two PTE table poiners, usually the kernel and current user |
1002 | * pointer to their respective root page table (pgdir). | |
1003 | */ | |
1004 | abatron_pteptrs: | |
1005 | .space 8 | |
1006 | ||
1007 | #ifdef CONFIG_8xx_CPU6 | |
1008 | .globl cpu6_errata_word | |
1009 | cpu6_errata_word: | |
1010 | .space 16 | |
1011 | #endif | |
1012 |