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9d02a428 JB |
1 | /* |
2 | * OpenRISC head.S | |
3 | * | |
4 | * Linux architectural port borrowing liberally from similar works of | |
5 | * others. All original copyrights apply as per the original source | |
6 | * declaration. | |
7 | * | |
8 | * Modifications for the OpenRISC architecture: | |
9 | * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com> | |
10 | * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | */ | |
17 | ||
18 | #include <linux/linkage.h> | |
19 | #include <linux/threads.h> | |
20 | #include <linux/errno.h> | |
21 | #include <linux/init.h> | |
160d8378 | 22 | #include <linux/serial_reg.h> |
9d02a428 JB |
23 | #include <asm/processor.h> |
24 | #include <asm/page.h> | |
25 | #include <asm/mmu.h> | |
26 | #include <asm/pgtable.h> | |
27 | #include <asm/cache.h> | |
28 | #include <asm/spr_defs.h> | |
29 | #include <asm/asm-offsets.h> | |
dec83018 | 30 | #include <linux/of_fdt.h> |
9d02a428 JB |
31 | |
32 | #define tophys(rd,rs) \ | |
33 | l.movhi rd,hi(-KERNELBASE) ;\ | |
34 | l.add rd,rd,rs | |
35 | ||
36 | #define CLEAR_GPR(gpr) \ | |
37 | l.or gpr,r0,r0 | |
38 | ||
39 | #define LOAD_SYMBOL_2_GPR(gpr,symbol) \ | |
40 | l.movhi gpr,hi(symbol) ;\ | |
41 | l.ori gpr,gpr,lo(symbol) | |
42 | ||
43 | ||
44 | #define UART_BASE_ADD 0x90000000 | |
45 | ||
46 | #define EXCEPTION_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_DCE | SPR_SR_ICE | SPR_SR_SM) | |
47 | #define SYSCALL_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_DCE | SPR_SR_ICE | SPR_SR_IEE | SPR_SR_TEE | SPR_SR_SM) | |
48 | ||
49 | /* ============================================[ tmp store locations ]=== */ | |
50 | ||
51 | /* | |
52 | * emergency_print temporary stores | |
53 | */ | |
54 | #define EMERGENCY_PRINT_STORE_GPR4 l.sw 0x20(r0),r4 | |
55 | #define EMERGENCY_PRINT_LOAD_GPR4 l.lwz r4,0x20(r0) | |
56 | ||
57 | #define EMERGENCY_PRINT_STORE_GPR5 l.sw 0x24(r0),r5 | |
58 | #define EMERGENCY_PRINT_LOAD_GPR5 l.lwz r5,0x24(r0) | |
59 | ||
60 | #define EMERGENCY_PRINT_STORE_GPR6 l.sw 0x28(r0),r6 | |
61 | #define EMERGENCY_PRINT_LOAD_GPR6 l.lwz r6,0x28(r0) | |
62 | ||
63 | #define EMERGENCY_PRINT_STORE_GPR7 l.sw 0x2c(r0),r7 | |
64 | #define EMERGENCY_PRINT_LOAD_GPR7 l.lwz r7,0x2c(r0) | |
65 | ||
66 | #define EMERGENCY_PRINT_STORE_GPR8 l.sw 0x30(r0),r8 | |
67 | #define EMERGENCY_PRINT_LOAD_GPR8 l.lwz r8,0x30(r0) | |
68 | ||
69 | #define EMERGENCY_PRINT_STORE_GPR9 l.sw 0x34(r0),r9 | |
70 | #define EMERGENCY_PRINT_LOAD_GPR9 l.lwz r9,0x34(r0) | |
71 | ||
72 | ||
73 | /* | |
74 | * TLB miss handlers temorary stores | |
75 | */ | |
76 | #define EXCEPTION_STORE_GPR9 l.sw 0x10(r0),r9 | |
77 | #define EXCEPTION_LOAD_GPR9 l.lwz r9,0x10(r0) | |
78 | ||
79 | #define EXCEPTION_STORE_GPR2 l.sw 0x64(r0),r2 | |
80 | #define EXCEPTION_LOAD_GPR2 l.lwz r2,0x64(r0) | |
81 | ||
82 | #define EXCEPTION_STORE_GPR3 l.sw 0x68(r0),r3 | |
83 | #define EXCEPTION_LOAD_GPR3 l.lwz r3,0x68(r0) | |
84 | ||
85 | #define EXCEPTION_STORE_GPR4 l.sw 0x6c(r0),r4 | |
86 | #define EXCEPTION_LOAD_GPR4 l.lwz r4,0x6c(r0) | |
87 | ||
88 | #define EXCEPTION_STORE_GPR5 l.sw 0x70(r0),r5 | |
89 | #define EXCEPTION_LOAD_GPR5 l.lwz r5,0x70(r0) | |
90 | ||
91 | #define EXCEPTION_STORE_GPR6 l.sw 0x74(r0),r6 | |
92 | #define EXCEPTION_LOAD_GPR6 l.lwz r6,0x74(r0) | |
93 | ||
94 | ||
95 | /* | |
96 | * EXCEPTION_HANDLE temporary stores | |
97 | */ | |
98 | ||
99 | #define EXCEPTION_T_STORE_GPR30 l.sw 0x78(r0),r30 | |
100 | #define EXCEPTION_T_LOAD_GPR30(reg) l.lwz reg,0x78(r0) | |
101 | ||
102 | #define EXCEPTION_T_STORE_GPR10 l.sw 0x7c(r0),r10 | |
103 | #define EXCEPTION_T_LOAD_GPR10(reg) l.lwz reg,0x7c(r0) | |
104 | ||
105 | #define EXCEPTION_T_STORE_SP l.sw 0x80(r0),r1 | |
106 | #define EXCEPTION_T_LOAD_SP(reg) l.lwz reg,0x80(r0) | |
107 | ||
108 | /* | |
109 | * For UNHANLDED_EXCEPTION | |
110 | */ | |
111 | ||
112 | #define EXCEPTION_T_STORE_GPR31 l.sw 0x84(r0),r31 | |
113 | #define EXCEPTION_T_LOAD_GPR31(reg) l.lwz reg,0x84(r0) | |
114 | ||
115 | /* =========================================================[ macros ]=== */ | |
116 | ||
117 | ||
118 | #define GET_CURRENT_PGD(reg,t1) \ | |
119 | LOAD_SYMBOL_2_GPR(reg,current_pgd) ;\ | |
120 | tophys (t1,reg) ;\ | |
121 | l.lwz reg,0(t1) | |
122 | ||
123 | ||
124 | /* | |
125 | * DSCR: this is a common hook for handling exceptions. it will save | |
126 | * the needed registers, set up stack and pointer to current | |
127 | * then jump to the handler while enabling MMU | |
128 | * | |
129 | * PRMS: handler - a function to jump to. it has to save the | |
130 | * remaining registers to kernel stack, call | |
131 | * appropriate arch-independant exception handler | |
132 | * and finaly jump to ret_from_except | |
133 | * | |
134 | * PREQ: unchanged state from the time exception happened | |
135 | * | |
136 | * POST: SAVED the following registers original value | |
137 | * to the new created exception frame pointed to by r1 | |
138 | * | |
139 | * r1 - ksp pointing to the new (exception) frame | |
140 | * r4 - EEAR exception EA | |
141 | * r10 - current pointing to current_thread_info struct | |
142 | * r12 - syscall 0, since we didn't come from syscall | |
143 | * r13 - temp it actually contains new SR, not needed anymore | |
144 | * r31 - handler address of the handler we'll jump to | |
145 | * | |
146 | * handler has to save remaining registers to the exception | |
147 | * ksp frame *before* tainting them! | |
148 | * | |
149 | * NOTE: this function is not reentrant per se. reentrancy is guaranteed | |
150 | * by processor disabling all exceptions/interrupts when exception | |
151 | * accours. | |
152 | * | |
153 | * OPTM: no need to make it so wasteful to extract ksp when in user mode | |
154 | */ | |
155 | ||
156 | #define EXCEPTION_HANDLE(handler) \ | |
157 | EXCEPTION_T_STORE_GPR30 ;\ | |
158 | l.mfspr r30,r0,SPR_ESR_BASE ;\ | |
159 | l.andi r30,r30,SPR_SR_SM ;\ | |
160 | l.sfeqi r30,0 ;\ | |
161 | EXCEPTION_T_STORE_GPR10 ;\ | |
162 | l.bnf 2f /* kernel_mode */ ;\ | |
163 | EXCEPTION_T_STORE_SP /* delay slot */ ;\ | |
164 | 1: /* user_mode: */ ;\ | |
165 | LOAD_SYMBOL_2_GPR(r1,current_thread_info_set) ;\ | |
166 | tophys (r30,r1) ;\ | |
167 | /* r10: current_thread_info */ ;\ | |
168 | l.lwz r10,0(r30) ;\ | |
169 | tophys (r30,r10) ;\ | |
170 | l.lwz r1,(TI_KSP)(r30) ;\ | |
171 | /* fall through */ ;\ | |
172 | 2: /* kernel_mode: */ ;\ | |
173 | /* create new stack frame, save only needed gprs */ ;\ | |
174 | /* r1: KSP, r10: current, r4: EEAR, r31: __pa(KSP) */ ;\ | |
175 | /* r12: temp, syscall indicator */ ;\ | |
176 | l.addi r1,r1,-(INT_FRAME_SIZE) ;\ | |
177 | /* r1 is KSP, r30 is __pa(KSP) */ ;\ | |
178 | tophys (r30,r1) ;\ | |
179 | l.sw PT_GPR12(r30),r12 ;\ | |
180 | l.mfspr r12,r0,SPR_EPCR_BASE ;\ | |
181 | l.sw PT_PC(r30),r12 ;\ | |
182 | l.mfspr r12,r0,SPR_ESR_BASE ;\ | |
183 | l.sw PT_SR(r30),r12 ;\ | |
184 | /* save r30 */ ;\ | |
185 | EXCEPTION_T_LOAD_GPR30(r12) ;\ | |
186 | l.sw PT_GPR30(r30),r12 ;\ | |
187 | /* save r10 as was prior to exception */ ;\ | |
188 | EXCEPTION_T_LOAD_GPR10(r12) ;\ | |
189 | l.sw PT_GPR10(r30),r12 ;\ | |
190 | /* save PT_SP as was prior to exception */ ;\ | |
191 | EXCEPTION_T_LOAD_SP(r12) ;\ | |
192 | l.sw PT_SP(r30),r12 ;\ | |
193 | /* save exception r4, set r4 = EA */ ;\ | |
194 | l.sw PT_GPR4(r30),r4 ;\ | |
195 | l.mfspr r4,r0,SPR_EEAR_BASE ;\ | |
196 | /* r12 == 1 if we come from syscall */ ;\ | |
197 | CLEAR_GPR(r12) ;\ | |
198 | /* ----- turn on MMU ----- */ ;\ | |
199 | l.ori r30,r0,(EXCEPTION_SR) ;\ | |
200 | l.mtspr r0,r30,SPR_ESR_BASE ;\ | |
201 | /* r30: EA address of handler */ ;\ | |
202 | LOAD_SYMBOL_2_GPR(r30,handler) ;\ | |
203 | l.mtspr r0,r30,SPR_EPCR_BASE ;\ | |
204 | l.rfe | |
205 | ||
206 | /* | |
207 | * this doesn't work | |
208 | * | |
209 | * | |
210 | * #ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION | |
211 | * #define UNHANDLED_EXCEPTION(handler) \ | |
212 | * l.ori r3,r0,0x1 ;\ | |
213 | * l.mtspr r0,r3,SPR_SR ;\ | |
214 | * l.movhi r3,hi(0xf0000100) ;\ | |
215 | * l.ori r3,r3,lo(0xf0000100) ;\ | |
216 | * l.jr r3 ;\ | |
217 | * l.nop 1 | |
218 | * | |
219 | * #endif | |
220 | */ | |
221 | ||
222 | /* DSCR: this is the same as EXCEPTION_HANDLE(), we are just | |
223 | * a bit more carefull (if we have a PT_SP or current pointer | |
224 | * corruption) and set them up from 'current_set' | |
225 | * | |
226 | */ | |
227 | #define UNHANDLED_EXCEPTION(handler) \ | |
228 | EXCEPTION_T_STORE_GPR31 ;\ | |
229 | EXCEPTION_T_STORE_GPR10 ;\ | |
230 | EXCEPTION_T_STORE_SP ;\ | |
231 | /* temporary store r3, r9 into r1, r10 */ ;\ | |
232 | l.addi r1,r3,0x0 ;\ | |
233 | l.addi r10,r9,0x0 ;\ | |
234 | /* the string referenced by r3 must be low enough */ ;\ | |
235 | l.jal _emergency_print ;\ | |
236 | l.ori r3,r0,lo(_string_unhandled_exception) ;\ | |
237 | l.mfspr r3,r0,SPR_NPC ;\ | |
238 | l.jal _emergency_print_nr ;\ | |
239 | l.andi r3,r3,0x1f00 ;\ | |
240 | /* the string referenced by r3 must be low enough */ ;\ | |
241 | l.jal _emergency_print ;\ | |
242 | l.ori r3,r0,lo(_string_epc_prefix) ;\ | |
243 | l.jal _emergency_print_nr ;\ | |
244 | l.mfspr r3,r0,SPR_EPCR_BASE ;\ | |
245 | l.jal _emergency_print ;\ | |
246 | l.ori r3,r0,lo(_string_nl) ;\ | |
247 | /* end of printing */ ;\ | |
248 | l.addi r3,r1,0x0 ;\ | |
249 | l.addi r9,r10,0x0 ;\ | |
250 | /* extract current, ksp from current_set */ ;\ | |
251 | LOAD_SYMBOL_2_GPR(r1,_unhandled_stack_top) ;\ | |
252 | LOAD_SYMBOL_2_GPR(r10,init_thread_union) ;\ | |
253 | /* create new stack frame, save only needed gprs */ ;\ | |
254 | /* r1: KSP, r10: current, r31: __pa(KSP) */ ;\ | |
255 | /* r12: temp, syscall indicator, r13 temp */ ;\ | |
256 | l.addi r1,r1,-(INT_FRAME_SIZE) ;\ | |
257 | /* r1 is KSP, r31 is __pa(KSP) */ ;\ | |
258 | tophys (r31,r1) ;\ | |
259 | l.sw PT_GPR12(r31),r12 ;\ | |
260 | l.mfspr r12,r0,SPR_EPCR_BASE ;\ | |
261 | l.sw PT_PC(r31),r12 ;\ | |
262 | l.mfspr r12,r0,SPR_ESR_BASE ;\ | |
263 | l.sw PT_SR(r31),r12 ;\ | |
264 | /* save r31 */ ;\ | |
265 | EXCEPTION_T_LOAD_GPR31(r12) ;\ | |
266 | l.sw PT_GPR31(r31),r12 ;\ | |
267 | /* save r10 as was prior to exception */ ;\ | |
268 | EXCEPTION_T_LOAD_GPR10(r12) ;\ | |
269 | l.sw PT_GPR10(r31),r12 ;\ | |
270 | /* save PT_SP as was prior to exception */ ;\ | |
271 | EXCEPTION_T_LOAD_SP(r12) ;\ | |
272 | l.sw PT_SP(r31),r12 ;\ | |
273 | l.sw PT_GPR13(r31),r13 ;\ | |
274 | /* --> */ ;\ | |
275 | /* save exception r4, set r4 = EA */ ;\ | |
276 | l.sw PT_GPR4(r31),r4 ;\ | |
277 | l.mfspr r4,r0,SPR_EEAR_BASE ;\ | |
278 | /* r12 == 1 if we come from syscall */ ;\ | |
279 | CLEAR_GPR(r12) ;\ | |
280 | /* ----- play a MMU trick ----- */ ;\ | |
281 | l.ori r31,r0,(EXCEPTION_SR) ;\ | |
282 | l.mtspr r0,r31,SPR_ESR_BASE ;\ | |
283 | /* r31: EA address of handler */ ;\ | |
284 | LOAD_SYMBOL_2_GPR(r31,handler) ;\ | |
285 | l.mtspr r0,r31,SPR_EPCR_BASE ;\ | |
286 | l.rfe | |
287 | ||
288 | /* =====================================================[ exceptions] === */ | |
289 | ||
290 | /* ---[ 0x100: RESET exception ]----------------------------------------- */ | |
291 | .org 0x100 | |
292 | /* Jump to .init code at _start which lives in the .head section | |
293 | * and will be discarded after boot. | |
294 | */ | |
54bd7c51 SK |
295 | LOAD_SYMBOL_2_GPR(r15, _start) |
296 | tophys (r13,r15) /* MMU disabled */ | |
297 | l.jr r13 | |
9d02a428 JB |
298 | l.nop |
299 | ||
300 | /* ---[ 0x200: BUS exception ]------------------------------------------- */ | |
301 | .org 0x200 | |
302 | _dispatch_bus_fault: | |
303 | EXCEPTION_HANDLE(_bus_fault_handler) | |
304 | ||
305 | /* ---[ 0x300: Data Page Fault exception ]------------------------------- */ | |
306 | .org 0x300 | |
307 | _dispatch_do_dpage_fault: | |
308 | // totaly disable timer interrupt | |
309 | // l.mtspr r0,r0,SPR_TTMR | |
310 | // DEBUG_TLB_PROBE(0x300) | |
311 | // EXCEPTION_DEBUG_VALUE_ER_ENABLED(0x300) | |
312 | EXCEPTION_HANDLE(_data_page_fault_handler) | |
313 | ||
314 | /* ---[ 0x400: Insn Page Fault exception ]------------------------------- */ | |
315 | .org 0x400 | |
316 | _dispatch_do_ipage_fault: | |
317 | // totaly disable timer interrupt | |
318 | // l.mtspr r0,r0,SPR_TTMR | |
319 | // DEBUG_TLB_PROBE(0x400) | |
320 | // EXCEPTION_DEBUG_VALUE_ER_ENABLED(0x400) | |
321 | EXCEPTION_HANDLE(_insn_page_fault_handler) | |
322 | ||
323 | /* ---[ 0x500: Timer exception ]----------------------------------------- */ | |
324 | .org 0x500 | |
325 | EXCEPTION_HANDLE(_timer_handler) | |
326 | ||
327 | /* ---[ 0x600: Aligment exception ]-------------------------------------- */ | |
328 | .org 0x600 | |
329 | EXCEPTION_HANDLE(_alignment_handler) | |
330 | ||
331 | /* ---[ 0x700: Illegal insn exception ]---------------------------------- */ | |
332 | .org 0x700 | |
333 | EXCEPTION_HANDLE(_illegal_instruction_handler) | |
334 | ||
335 | /* ---[ 0x800: External interrupt exception ]---------------------------- */ | |
336 | .org 0x800 | |
337 | EXCEPTION_HANDLE(_external_irq_handler) | |
338 | ||
339 | /* ---[ 0x900: DTLB miss exception ]------------------------------------- */ | |
340 | .org 0x900 | |
341 | l.j boot_dtlb_miss_handler | |
342 | l.nop | |
343 | ||
344 | /* ---[ 0xa00: ITLB miss exception ]------------------------------------- */ | |
345 | .org 0xa00 | |
346 | l.j boot_itlb_miss_handler | |
347 | l.nop | |
348 | ||
349 | /* ---[ 0xb00: Range exception ]----------------------------------------- */ | |
350 | .org 0xb00 | |
351 | UNHANDLED_EXCEPTION(_vector_0xb00) | |
352 | ||
353 | /* ---[ 0xc00: Syscall exception ]--------------------------------------- */ | |
354 | .org 0xc00 | |
355 | EXCEPTION_HANDLE(_sys_call_handler) | |
356 | ||
357 | /* ---[ 0xd00: Trap exception ]------------------------------------------ */ | |
358 | .org 0xd00 | |
359 | UNHANDLED_EXCEPTION(_vector_0xd00) | |
360 | ||
361 | /* ---[ 0xe00: Trap exception ]------------------------------------------ */ | |
362 | .org 0xe00 | |
363 | // UNHANDLED_EXCEPTION(_vector_0xe00) | |
364 | EXCEPTION_HANDLE(_trap_handler) | |
365 | ||
366 | /* ---[ 0xf00: Reserved exception ]-------------------------------------- */ | |
367 | .org 0xf00 | |
368 | UNHANDLED_EXCEPTION(_vector_0xf00) | |
369 | ||
370 | /* ---[ 0x1000: Reserved exception ]------------------------------------- */ | |
371 | .org 0x1000 | |
372 | UNHANDLED_EXCEPTION(_vector_0x1000) | |
373 | ||
374 | /* ---[ 0x1100: Reserved exception ]------------------------------------- */ | |
375 | .org 0x1100 | |
376 | UNHANDLED_EXCEPTION(_vector_0x1100) | |
377 | ||
378 | /* ---[ 0x1200: Reserved exception ]------------------------------------- */ | |
379 | .org 0x1200 | |
380 | UNHANDLED_EXCEPTION(_vector_0x1200) | |
381 | ||
382 | /* ---[ 0x1300: Reserved exception ]------------------------------------- */ | |
383 | .org 0x1300 | |
384 | UNHANDLED_EXCEPTION(_vector_0x1300) | |
385 | ||
386 | /* ---[ 0x1400: Reserved exception ]------------------------------------- */ | |
387 | .org 0x1400 | |
388 | UNHANDLED_EXCEPTION(_vector_0x1400) | |
389 | ||
390 | /* ---[ 0x1500: Reserved exception ]------------------------------------- */ | |
391 | .org 0x1500 | |
392 | UNHANDLED_EXCEPTION(_vector_0x1500) | |
393 | ||
394 | /* ---[ 0x1600: Reserved exception ]------------------------------------- */ | |
395 | .org 0x1600 | |
396 | UNHANDLED_EXCEPTION(_vector_0x1600) | |
397 | ||
398 | /* ---[ 0x1700: Reserved exception ]------------------------------------- */ | |
399 | .org 0x1700 | |
400 | UNHANDLED_EXCEPTION(_vector_0x1700) | |
401 | ||
402 | /* ---[ 0x1800: Reserved exception ]------------------------------------- */ | |
403 | .org 0x1800 | |
404 | UNHANDLED_EXCEPTION(_vector_0x1800) | |
405 | ||
406 | /* ---[ 0x1900: Reserved exception ]------------------------------------- */ | |
407 | .org 0x1900 | |
408 | UNHANDLED_EXCEPTION(_vector_0x1900) | |
409 | ||
410 | /* ---[ 0x1a00: Reserved exception ]------------------------------------- */ | |
411 | .org 0x1a00 | |
412 | UNHANDLED_EXCEPTION(_vector_0x1a00) | |
413 | ||
414 | /* ---[ 0x1b00: Reserved exception ]------------------------------------- */ | |
415 | .org 0x1b00 | |
416 | UNHANDLED_EXCEPTION(_vector_0x1b00) | |
417 | ||
418 | /* ---[ 0x1c00: Reserved exception ]------------------------------------- */ | |
419 | .org 0x1c00 | |
420 | UNHANDLED_EXCEPTION(_vector_0x1c00) | |
421 | ||
422 | /* ---[ 0x1d00: Reserved exception ]------------------------------------- */ | |
423 | .org 0x1d00 | |
424 | UNHANDLED_EXCEPTION(_vector_0x1d00) | |
425 | ||
426 | /* ---[ 0x1e00: Reserved exception ]------------------------------------- */ | |
427 | .org 0x1e00 | |
428 | UNHANDLED_EXCEPTION(_vector_0x1e00) | |
429 | ||
430 | /* ---[ 0x1f00: Reserved exception ]------------------------------------- */ | |
431 | .org 0x1f00 | |
432 | UNHANDLED_EXCEPTION(_vector_0x1f00) | |
433 | ||
434 | .org 0x2000 | |
435 | /* ===================================================[ kernel start ]=== */ | |
436 | ||
437 | /* .text*/ | |
438 | ||
439 | /* This early stuff belongs in HEAD, but some of the functions below definitely | |
440 | * don't... */ | |
441 | ||
442 | __HEAD | |
443 | .global _start | |
444 | _start: | |
dec83018 SK |
445 | /* save kernel parameters */ |
446 | l.or r25,r0,r3 /* pointer to fdt */ | |
447 | ||
9d02a428 JB |
448 | /* |
449 | * ensure a deterministic start | |
450 | */ | |
451 | ||
452 | l.ori r3,r0,0x1 | |
453 | l.mtspr r0,r3,SPR_SR | |
454 | ||
455 | CLEAR_GPR(r1) | |
456 | CLEAR_GPR(r2) | |
457 | CLEAR_GPR(r3) | |
458 | CLEAR_GPR(r4) | |
459 | CLEAR_GPR(r5) | |
460 | CLEAR_GPR(r6) | |
461 | CLEAR_GPR(r7) | |
462 | CLEAR_GPR(r8) | |
463 | CLEAR_GPR(r9) | |
464 | CLEAR_GPR(r10) | |
465 | CLEAR_GPR(r11) | |
466 | CLEAR_GPR(r12) | |
467 | CLEAR_GPR(r13) | |
468 | CLEAR_GPR(r14) | |
469 | CLEAR_GPR(r15) | |
470 | CLEAR_GPR(r16) | |
471 | CLEAR_GPR(r17) | |
472 | CLEAR_GPR(r18) | |
473 | CLEAR_GPR(r19) | |
474 | CLEAR_GPR(r20) | |
475 | CLEAR_GPR(r21) | |
476 | CLEAR_GPR(r22) | |
477 | CLEAR_GPR(r23) | |
478 | CLEAR_GPR(r24) | |
9d02a428 JB |
479 | CLEAR_GPR(r26) |
480 | CLEAR_GPR(r27) | |
481 | CLEAR_GPR(r28) | |
482 | CLEAR_GPR(r29) | |
483 | CLEAR_GPR(r30) | |
484 | CLEAR_GPR(r31) | |
485 | ||
486 | /* | |
487 | * set up initial ksp and current | |
488 | */ | |
489 | LOAD_SYMBOL_2_GPR(r1,init_thread_union+0x2000) // setup kernel stack | |
490 | LOAD_SYMBOL_2_GPR(r10,init_thread_union) // setup current | |
491 | tophys (r31,r10) | |
492 | l.sw TI_KSP(r31), r1 | |
493 | ||
494 | l.ori r4,r0,0x0 | |
495 | ||
496 | ||
497 | /* | |
498 | * .data contains initialized data, | |
499 | * .bss contains uninitialized data - clear it up | |
500 | */ | |
501 | clear_bss: | |
502 | LOAD_SYMBOL_2_GPR(r24, __bss_start) | |
503 | LOAD_SYMBOL_2_GPR(r26, _end) | |
504 | tophys(r28,r24) | |
505 | tophys(r30,r26) | |
506 | CLEAR_GPR(r24) | |
507 | CLEAR_GPR(r26) | |
508 | 1: | |
509 | l.sw (0)(r28),r0 | |
510 | l.sfltu r28,r30 | |
511 | l.bf 1b | |
512 | l.addi r28,r28,4 | |
513 | ||
514 | enable_ic: | |
515 | l.jal _ic_enable | |
516 | l.nop | |
517 | ||
518 | enable_dc: | |
519 | l.jal _dc_enable | |
520 | l.nop | |
521 | ||
522 | flush_tlb: | |
523 | /* | |
524 | * I N V A L I D A T E T L B e n t r i e s | |
525 | */ | |
526 | LOAD_SYMBOL_2_GPR(r5,SPR_DTLBMR_BASE(0)) | |
527 | LOAD_SYMBOL_2_GPR(r6,SPR_ITLBMR_BASE(0)) | |
528 | l.addi r7,r0,128 /* Maximum number of sets */ | |
529 | 1: | |
530 | l.mtspr r5,r0,0x0 | |
531 | l.mtspr r6,r0,0x0 | |
532 | ||
533 | l.addi r5,r5,1 | |
534 | l.addi r6,r6,1 | |
535 | l.sfeq r7,r0 | |
536 | l.bnf 1b | |
537 | l.addi r7,r7,-1 | |
538 | ||
539 | ||
540 | /* The MMU needs to be enabled before or32_early_setup is called */ | |
541 | ||
542 | enable_mmu: | |
543 | /* | |
544 | * enable dmmu & immu | |
545 | * SR[5] = 0, SR[6] = 0, 6th and 7th bit of SR set to 0 | |
546 | */ | |
547 | l.mfspr r30,r0,SPR_SR | |
548 | l.movhi r28,hi(SPR_SR_DME | SPR_SR_IME) | |
549 | l.ori r28,r28,lo(SPR_SR_DME | SPR_SR_IME) | |
550 | l.or r30,r30,r28 | |
551 | l.mtspr r0,r30,SPR_SR | |
552 | l.nop | |
553 | l.nop | |
554 | l.nop | |
555 | l.nop | |
556 | l.nop | |
557 | l.nop | |
558 | l.nop | |
559 | l.nop | |
560 | l.nop | |
561 | l.nop | |
562 | l.nop | |
563 | l.nop | |
564 | l.nop | |
565 | l.nop | |
566 | l.nop | |
567 | l.nop | |
568 | ||
569 | // reset the simulation counters | |
570 | l.nop 5 | |
571 | ||
dec83018 SK |
572 | /* check fdt header magic word */ |
573 | l.lwz r3,0(r25) /* load magic from fdt into r3 */ | |
574 | l.movhi r4,hi(OF_DT_HEADER) | |
575 | l.ori r4,r4,lo(OF_DT_HEADER) | |
576 | l.sfeq r3,r4 | |
577 | l.bf _fdt_found | |
578 | l.nop | |
579 | /* magic number mismatch, set fdt pointer to null */ | |
580 | l.or r25,r0,r0 | |
581 | _fdt_found: | |
582 | /* pass fdt pointer to or32_early_setup in r3 */ | |
583 | l.or r3,r0,r25 | |
9d02a428 JB |
584 | LOAD_SYMBOL_2_GPR(r24, or32_early_setup) |
585 | l.jalr r24 | |
586 | l.nop | |
587 | ||
588 | clear_regs: | |
589 | /* | |
590 | * clear all GPRS to increase determinism | |
591 | */ | |
592 | CLEAR_GPR(r2) | |
593 | CLEAR_GPR(r3) | |
594 | CLEAR_GPR(r4) | |
595 | CLEAR_GPR(r5) | |
596 | CLEAR_GPR(r6) | |
597 | CLEAR_GPR(r7) | |
598 | CLEAR_GPR(r8) | |
599 | CLEAR_GPR(r9) | |
600 | CLEAR_GPR(r11) | |
601 | CLEAR_GPR(r12) | |
602 | CLEAR_GPR(r13) | |
603 | CLEAR_GPR(r14) | |
604 | CLEAR_GPR(r15) | |
605 | CLEAR_GPR(r16) | |
606 | CLEAR_GPR(r17) | |
607 | CLEAR_GPR(r18) | |
608 | CLEAR_GPR(r19) | |
609 | CLEAR_GPR(r20) | |
610 | CLEAR_GPR(r21) | |
611 | CLEAR_GPR(r22) | |
612 | CLEAR_GPR(r23) | |
613 | CLEAR_GPR(r24) | |
614 | CLEAR_GPR(r25) | |
615 | CLEAR_GPR(r26) | |
616 | CLEAR_GPR(r27) | |
617 | CLEAR_GPR(r28) | |
618 | CLEAR_GPR(r29) | |
619 | CLEAR_GPR(r30) | |
620 | CLEAR_GPR(r31) | |
621 | ||
622 | jump_start_kernel: | |
623 | /* | |
624 | * jump to kernel entry (start_kernel) | |
625 | */ | |
626 | LOAD_SYMBOL_2_GPR(r30, start_kernel) | |
627 | l.jr r30 | |
628 | l.nop | |
629 | ||
630 | /* ========================================[ cache ]=== */ | |
631 | ||
632 | /* aligment here so we don't change memory offsets with | |
633 | * memory controler defined | |
634 | */ | |
635 | .align 0x2000 | |
636 | ||
637 | _ic_enable: | |
638 | /* Check if IC present and skip enabling otherwise */ | |
639 | l.mfspr r24,r0,SPR_UPR | |
640 | l.andi r26,r24,SPR_UPR_ICP | |
641 | l.sfeq r26,r0 | |
642 | l.bf 9f | |
643 | l.nop | |
644 | ||
645 | /* Disable IC */ | |
646 | l.mfspr r6,r0,SPR_SR | |
647 | l.addi r5,r0,-1 | |
648 | l.xori r5,r5,SPR_SR_ICE | |
649 | l.and r5,r6,r5 | |
650 | l.mtspr r0,r5,SPR_SR | |
651 | ||
652 | /* Establish cache block size | |
653 | If BS=0, 16; | |
654 | If BS=1, 32; | |
655 | r14 contain block size | |
656 | */ | |
657 | l.mfspr r24,r0,SPR_ICCFGR | |
658 | l.andi r26,r24,SPR_ICCFGR_CBS | |
659 | l.srli r28,r26,7 | |
660 | l.ori r30,r0,16 | |
661 | l.sll r14,r30,r28 | |
662 | ||
663 | /* Establish number of cache sets | |
664 | r16 contains number of cache sets | |
665 | r28 contains log(# of cache sets) | |
666 | */ | |
667 | l.andi r26,r24,SPR_ICCFGR_NCS | |
668 | l.srli r28,r26,3 | |
669 | l.ori r30,r0,1 | |
670 | l.sll r16,r30,r28 | |
671 | ||
672 | /* Invalidate IC */ | |
673 | l.addi r6,r0,0 | |
674 | l.sll r5,r14,r28 | |
675 | // l.mul r5,r14,r16 | |
676 | // l.trap 1 | |
677 | // l.addi r5,r0,IC_SIZE | |
678 | 1: | |
679 | l.mtspr r0,r6,SPR_ICBIR | |
680 | l.sfne r6,r5 | |
681 | l.bf 1b | |
682 | l.add r6,r6,r14 | |
683 | // l.addi r6,r6,IC_LINE | |
684 | ||
685 | /* Enable IC */ | |
686 | l.mfspr r6,r0,SPR_SR | |
687 | l.ori r6,r6,SPR_SR_ICE | |
688 | l.mtspr r0,r6,SPR_SR | |
689 | l.nop | |
690 | l.nop | |
691 | l.nop | |
692 | l.nop | |
693 | l.nop | |
694 | l.nop | |
695 | l.nop | |
696 | l.nop | |
697 | l.nop | |
698 | l.nop | |
699 | 9: | |
700 | l.jr r9 | |
701 | l.nop | |
702 | ||
703 | _dc_enable: | |
704 | /* Check if DC present and skip enabling otherwise */ | |
705 | l.mfspr r24,r0,SPR_UPR | |
706 | l.andi r26,r24,SPR_UPR_DCP | |
707 | l.sfeq r26,r0 | |
708 | l.bf 9f | |
709 | l.nop | |
710 | ||
711 | /* Disable DC */ | |
712 | l.mfspr r6,r0,SPR_SR | |
713 | l.addi r5,r0,-1 | |
714 | l.xori r5,r5,SPR_SR_DCE | |
715 | l.and r5,r6,r5 | |
716 | l.mtspr r0,r5,SPR_SR | |
717 | ||
718 | /* Establish cache block size | |
719 | If BS=0, 16; | |
720 | If BS=1, 32; | |
721 | r14 contain block size | |
722 | */ | |
723 | l.mfspr r24,r0,SPR_DCCFGR | |
724 | l.andi r26,r24,SPR_DCCFGR_CBS | |
725 | l.srli r28,r26,7 | |
726 | l.ori r30,r0,16 | |
727 | l.sll r14,r30,r28 | |
728 | ||
729 | /* Establish number of cache sets | |
730 | r16 contains number of cache sets | |
731 | r28 contains log(# of cache sets) | |
732 | */ | |
733 | l.andi r26,r24,SPR_DCCFGR_NCS | |
734 | l.srli r28,r26,3 | |
735 | l.ori r30,r0,1 | |
736 | l.sll r16,r30,r28 | |
737 | ||
738 | /* Invalidate DC */ | |
739 | l.addi r6,r0,0 | |
740 | l.sll r5,r14,r28 | |
741 | 1: | |
742 | l.mtspr r0,r6,SPR_DCBIR | |
743 | l.sfne r6,r5 | |
744 | l.bf 1b | |
745 | l.add r6,r6,r14 | |
746 | ||
747 | /* Enable DC */ | |
748 | l.mfspr r6,r0,SPR_SR | |
749 | l.ori r6,r6,SPR_SR_DCE | |
750 | l.mtspr r0,r6,SPR_SR | |
751 | 9: | |
752 | l.jr r9 | |
753 | l.nop | |
754 | ||
755 | /* ===============================================[ page table masks ]=== */ | |
756 | ||
757 | /* bit 4 is used in hardware as write back cache bit. we never use this bit | |
758 | * explicitly, so we can reuse it as _PAGE_FILE bit and mask it out when | |
759 | * writing into hardware pte's | |
760 | */ | |
761 | ||
762 | #define DTLB_UP_CONVERT_MASK 0x3fa | |
763 | #define ITLB_UP_CONVERT_MASK 0x3a | |
764 | ||
765 | /* for SMP we'd have (this is a bit subtle, CC must be always set | |
766 | * for SMP, but since we have _PAGE_PRESENT bit always defined | |
767 | * we can just modify the mask) | |
768 | */ | |
769 | #define DTLB_SMP_CONVERT_MASK 0x3fb | |
770 | #define ITLB_SMP_CONVERT_MASK 0x3b | |
771 | ||
772 | /* ---[ boot dtlb miss handler ]----------------------------------------- */ | |
773 | ||
774 | boot_dtlb_miss_handler: | |
775 | ||
776 | /* mask for DTLB_MR register: - (0) sets V (valid) bit, | |
777 | * - (31-12) sets bits belonging to VPN (31-12) | |
778 | */ | |
779 | #define DTLB_MR_MASK 0xfffff001 | |
780 | ||
781 | /* mask for DTLB_TR register: - (2) sets CI (cache inhibit) bit, | |
782 | * - (4) sets A (access) bit, | |
783 | * - (5) sets D (dirty) bit, | |
784 | * - (8) sets SRE (superuser read) bit | |
785 | * - (9) sets SWE (superuser write) bit | |
786 | * - (31-12) sets bits belonging to VPN (31-12) | |
787 | */ | |
788 | #define DTLB_TR_MASK 0xfffff332 | |
789 | ||
790 | /* These are for masking out the VPN/PPN value from the MR/TR registers... | |
791 | * it's not the same as the PFN */ | |
792 | #define VPN_MASK 0xfffff000 | |
793 | #define PPN_MASK 0xfffff000 | |
794 | ||
795 | ||
796 | EXCEPTION_STORE_GPR6 | |
797 | ||
798 | #if 0 | |
799 | l.mfspr r6,r0,SPR_ESR_BASE // | |
800 | l.andi r6,r6,SPR_SR_SM // are we in kernel mode ? | |
801 | l.sfeqi r6,0 // r6 == 0x1 --> SM | |
802 | l.bf exit_with_no_dtranslation // | |
803 | l.nop | |
804 | #endif | |
805 | ||
806 | /* this could be optimized by moving storing of | |
807 | * non r6 registers here, and jumping r6 restore | |
808 | * if not in supervisor mode | |
809 | */ | |
810 | ||
811 | EXCEPTION_STORE_GPR2 | |
812 | EXCEPTION_STORE_GPR3 | |
813 | EXCEPTION_STORE_GPR4 | |
814 | EXCEPTION_STORE_GPR5 | |
815 | ||
816 | l.mfspr r4,r0,SPR_EEAR_BASE // get the offending EA | |
817 | ||
818 | immediate_translation: | |
819 | CLEAR_GPR(r6) | |
820 | ||
821 | l.srli r3,r4,0xd // r3 <- r4 / 8192 (sets are relative to page size (8Kb) NOT VPN size (4Kb) | |
822 | ||
823 | l.mfspr r6, r0, SPR_DMMUCFGR | |
824 | l.andi r6, r6, SPR_DMMUCFGR_NTS | |
825 | l.srli r6, r6, SPR_DMMUCFGR_NTS_OFF | |
826 | l.ori r5, r0, 0x1 | |
827 | l.sll r5, r5, r6 // r5 = number DMMU sets | |
828 | l.addi r6, r5, -1 // r6 = nsets mask | |
829 | l.and r2, r3, r6 // r2 <- r3 % NSETS_MASK | |
830 | ||
831 | l.or r6,r6,r4 // r6 <- r4 | |
832 | l.ori r6,r6,~(VPN_MASK) // r6 <- VPN :VPN .xfff - clear up lo(r6) to 0x**** *fff | |
833 | l.movhi r5,hi(DTLB_MR_MASK) // r5 <- ffff:0000.x000 | |
834 | l.ori r5,r5,lo(DTLB_MR_MASK) // r5 <- ffff:1111.x001 - apply DTLB_MR_MASK | |
835 | l.and r5,r5,r6 // r5 <- VPN :VPN .x001 - we have DTLBMR entry | |
836 | l.mtspr r2,r5,SPR_DTLBMR_BASE(0) // set DTLBMR | |
837 | ||
838 | /* set up DTLB with no translation for EA <= 0xbfffffff */ | |
839 | LOAD_SYMBOL_2_GPR(r6,0xbfffffff) | |
840 | l.sfgeu r6,r4 // flag if r6 >= r4 (if 0xbfffffff >= EA) | |
841 | l.bf 1f // goto out | |
842 | l.and r3,r4,r4 // delay slot :: 24 <- r4 (if flag==1) | |
843 | ||
844 | tophys(r3,r4) // r3 <- PA | |
845 | 1: | |
846 | l.ori r3,r3,~(PPN_MASK) // r3 <- PPN :PPN .xfff - clear up lo(r6) to 0x**** *fff | |
847 | l.movhi r5,hi(DTLB_TR_MASK) // r5 <- ffff:0000.x000 | |
848 | l.ori r5,r5,lo(DTLB_TR_MASK) // r5 <- ffff:1111.x330 - apply DTLB_MR_MASK | |
849 | l.and r5,r5,r3 // r5 <- PPN :PPN .x330 - we have DTLBTR entry | |
850 | l.mtspr r2,r5,SPR_DTLBTR_BASE(0) // set DTLBTR | |
851 | ||
852 | EXCEPTION_LOAD_GPR6 | |
853 | EXCEPTION_LOAD_GPR5 | |
854 | EXCEPTION_LOAD_GPR4 | |
855 | EXCEPTION_LOAD_GPR3 | |
856 | EXCEPTION_LOAD_GPR2 | |
857 | ||
858 | l.rfe // SR <- ESR, PC <- EPC | |
859 | ||
860 | exit_with_no_dtranslation: | |
861 | /* EA out of memory or not in supervisor mode */ | |
862 | EXCEPTION_LOAD_GPR6 | |
863 | EXCEPTION_LOAD_GPR4 | |
864 | l.j _dispatch_bus_fault | |
865 | ||
866 | /* ---[ boot itlb miss handler ]----------------------------------------- */ | |
867 | ||
868 | boot_itlb_miss_handler: | |
869 | ||
870 | /* mask for ITLB_MR register: - sets V (valid) bit, | |
871 | * - sets bits belonging to VPN (15-12) | |
872 | */ | |
873 | #define ITLB_MR_MASK 0xfffff001 | |
874 | ||
875 | /* mask for ITLB_TR register: - sets A (access) bit, | |
876 | * - sets SXE (superuser execute) bit | |
877 | * - sets bits belonging to VPN (15-12) | |
878 | */ | |
879 | #define ITLB_TR_MASK 0xfffff050 | |
880 | ||
881 | /* | |
882 | #define VPN_MASK 0xffffe000 | |
883 | #define PPN_MASK 0xffffe000 | |
884 | */ | |
885 | ||
886 | ||
887 | ||
888 | EXCEPTION_STORE_GPR2 | |
889 | EXCEPTION_STORE_GPR3 | |
890 | EXCEPTION_STORE_GPR4 | |
891 | EXCEPTION_STORE_GPR5 | |
892 | EXCEPTION_STORE_GPR6 | |
893 | ||
894 | #if 0 | |
895 | l.mfspr r6,r0,SPR_ESR_BASE // | |
896 | l.andi r6,r6,SPR_SR_SM // are we in kernel mode ? | |
897 | l.sfeqi r6,0 // r6 == 0x1 --> SM | |
898 | l.bf exit_with_no_itranslation | |
899 | l.nop | |
900 | #endif | |
901 | ||
902 | ||
903 | l.mfspr r4,r0,SPR_EEAR_BASE // get the offending EA | |
904 | ||
905 | earlyearly: | |
906 | CLEAR_GPR(r6) | |
907 | ||
908 | l.srli r3,r4,0xd // r3 <- r4 / 8192 (sets are relative to page size (8Kb) NOT VPN size (4Kb) | |
909 | ||
910 | l.mfspr r6, r0, SPR_IMMUCFGR | |
911 | l.andi r6, r6, SPR_IMMUCFGR_NTS | |
912 | l.srli r6, r6, SPR_IMMUCFGR_NTS_OFF | |
913 | l.ori r5, r0, 0x1 | |
914 | l.sll r5, r5, r6 // r5 = number IMMU sets from IMMUCFGR | |
915 | l.addi r6, r5, -1 // r6 = nsets mask | |
916 | l.and r2, r3, r6 // r2 <- r3 % NSETS_MASK | |
917 | ||
918 | l.or r6,r6,r4 // r6 <- r4 | |
919 | l.ori r6,r6,~(VPN_MASK) // r6 <- VPN :VPN .xfff - clear up lo(r6) to 0x**** *fff | |
920 | l.movhi r5,hi(ITLB_MR_MASK) // r5 <- ffff:0000.x000 | |
921 | l.ori r5,r5,lo(ITLB_MR_MASK) // r5 <- ffff:1111.x001 - apply ITLB_MR_MASK | |
922 | l.and r5,r5,r6 // r5 <- VPN :VPN .x001 - we have ITLBMR entry | |
923 | l.mtspr r2,r5,SPR_ITLBMR_BASE(0) // set ITLBMR | |
924 | ||
925 | /* | |
926 | * set up ITLB with no translation for EA <= 0x0fffffff | |
927 | * | |
928 | * we need this for head.S mapping (EA = PA). if we move all functions | |
929 | * which run with mmu enabled into entry.S, we might be able to eliminate this. | |
930 | * | |
931 | */ | |
932 | LOAD_SYMBOL_2_GPR(r6,0x0fffffff) | |
933 | l.sfgeu r6,r4 // flag if r6 >= r4 (if 0xb0ffffff >= EA) | |
934 | l.bf 1f // goto out | |
935 | l.and r3,r4,r4 // delay slot :: 24 <- r4 (if flag==1) | |
936 | ||
937 | tophys(r3,r4) // r3 <- PA | |
938 | 1: | |
939 | l.ori r3,r3,~(PPN_MASK) // r3 <- PPN :PPN .xfff - clear up lo(r6) to 0x**** *fff | |
940 | l.movhi r5,hi(ITLB_TR_MASK) // r5 <- ffff:0000.x000 | |
941 | l.ori r5,r5,lo(ITLB_TR_MASK) // r5 <- ffff:1111.x050 - apply ITLB_MR_MASK | |
942 | l.and r5,r5,r3 // r5 <- PPN :PPN .x050 - we have ITLBTR entry | |
943 | l.mtspr r2,r5,SPR_ITLBTR_BASE(0) // set ITLBTR | |
944 | ||
945 | EXCEPTION_LOAD_GPR6 | |
946 | EXCEPTION_LOAD_GPR5 | |
947 | EXCEPTION_LOAD_GPR4 | |
948 | EXCEPTION_LOAD_GPR3 | |
949 | EXCEPTION_LOAD_GPR2 | |
950 | ||
951 | l.rfe // SR <- ESR, PC <- EPC | |
952 | ||
953 | exit_with_no_itranslation: | |
954 | EXCEPTION_LOAD_GPR4 | |
955 | EXCEPTION_LOAD_GPR6 | |
956 | l.j _dispatch_bus_fault | |
957 | l.nop | |
958 | ||
959 | /* ====================================================================== */ | |
960 | /* | |
961 | * Stuff below here shouldn't go into .head section... maybe this stuff | |
962 | * can be moved to entry.S ??? | |
963 | */ | |
964 | ||
965 | /* ==============================================[ DTLB miss handler ]=== */ | |
966 | ||
967 | /* | |
968 | * Comments: | |
969 | * Exception handlers are entered with MMU off so the following handler | |
970 | * needs to use physical addressing | |
971 | * | |
972 | */ | |
973 | ||
974 | .text | |
975 | ENTRY(dtlb_miss_handler) | |
976 | EXCEPTION_STORE_GPR2 | |
977 | EXCEPTION_STORE_GPR3 | |
978 | EXCEPTION_STORE_GPR4 | |
979 | EXCEPTION_STORE_GPR5 | |
980 | EXCEPTION_STORE_GPR6 | |
981 | /* | |
982 | * get EA of the miss | |
983 | */ | |
984 | l.mfspr r2,r0,SPR_EEAR_BASE | |
985 | /* | |
986 | * pmd = (pmd_t *)(current_pgd + pgd_index(daddr)); | |
987 | */ | |
988 | GET_CURRENT_PGD(r3,r5) // r3 is current_pgd, r5 is temp | |
989 | l.srli r4,r2,0x18 // >> PAGE_SHIFT + (PAGE_SHIFT - 2) | |
990 | l.slli r4,r4,0x2 // to get address << 2 | |
991 | l.add r5,r4,r3 // r4 is pgd_index(daddr) | |
992 | /* | |
993 | * if (pmd_none(*pmd)) | |
994 | * goto pmd_none: | |
995 | */ | |
996 | tophys (r4,r5) | |
997 | l.lwz r3,0x0(r4) // get *pmd value | |
998 | l.sfne r3,r0 | |
999 | l.bnf d_pmd_none | |
1000 | l.andi r3,r3,~PAGE_MASK //0x1fff // ~PAGE_MASK | |
1001 | /* | |
1002 | * if (pmd_bad(*pmd)) | |
1003 | * pmd_clear(pmd) | |
1004 | * goto pmd_bad: | |
1005 | */ | |
1006 | // l.sfeq r3,r0 // check *pmd value | |
1007 | // l.bf d_pmd_good | |
1008 | l.addi r3,r0,0xffffe000 // PAGE_MASK | |
1009 | // l.j d_pmd_bad | |
1010 | // l.sw 0x0(r4),r0 // clear pmd | |
1011 | d_pmd_good: | |
1012 | /* | |
1013 | * pte = *pte_offset(pmd, daddr); | |
1014 | */ | |
1015 | l.lwz r4,0x0(r4) // get **pmd value | |
1016 | l.and r4,r4,r3 // & PAGE_MASK | |
1017 | l.srli r5,r2,0xd // >> PAGE_SHIFT, r2 == EEAR | |
1018 | l.andi r3,r5,0x7ff // (1UL << PAGE_SHIFT - 2) - 1 | |
1019 | l.slli r3,r3,0x2 // to get address << 2 | |
1020 | l.add r3,r3,r4 | |
1021 | l.lwz r2,0x0(r3) // this is pte at last | |
1022 | /* | |
1023 | * if (!pte_present(pte)) | |
1024 | */ | |
1025 | l.andi r4,r2,0x1 | |
1026 | l.sfne r4,r0 // is pte present | |
1027 | l.bnf d_pte_not_present | |
1028 | l.addi r3,r0,0xffffe3fa // PAGE_MASK | DTLB_UP_CONVERT_MASK | |
1029 | /* | |
1030 | * fill DTLB TR register | |
1031 | */ | |
1032 | l.and r4,r2,r3 // apply the mask | |
1033 | // Determine number of DMMU sets | |
1034 | l.mfspr r6, r0, SPR_DMMUCFGR | |
1035 | l.andi r6, r6, SPR_DMMUCFGR_NTS | |
1036 | l.srli r6, r6, SPR_DMMUCFGR_NTS_OFF | |
1037 | l.ori r3, r0, 0x1 | |
1038 | l.sll r3, r3, r6 // r3 = number DMMU sets DMMUCFGR | |
1039 | l.addi r6, r3, -1 // r6 = nsets mask | |
1040 | l.and r5, r5, r6 // calc offset: & (NUM_TLB_ENTRIES-1) | |
1041 | //NUM_TLB_ENTRIES | |
1042 | l.mtspr r5,r4,SPR_DTLBTR_BASE(0) | |
1043 | /* | |
1044 | * fill DTLB MR register | |
1045 | */ | |
1046 | l.mfspr r2,r0,SPR_EEAR_BASE | |
1047 | l.addi r3,r0,0xffffe000 // PAGE_MASK | |
1048 | l.and r4,r2,r3 // apply PAGE_MASK to EA (__PHX__ do we really need this?) | |
1049 | l.ori r4,r4,0x1 // set hardware valid bit: DTBL_MR entry | |
1050 | l.mtspr r5,r4,SPR_DTLBMR_BASE(0) | |
1051 | ||
1052 | EXCEPTION_LOAD_GPR2 | |
1053 | EXCEPTION_LOAD_GPR3 | |
1054 | EXCEPTION_LOAD_GPR4 | |
1055 | EXCEPTION_LOAD_GPR5 | |
1056 | EXCEPTION_LOAD_GPR6 | |
1057 | l.rfe | |
1058 | d_pmd_bad: | |
1059 | l.nop 1 | |
1060 | EXCEPTION_LOAD_GPR2 | |
1061 | EXCEPTION_LOAD_GPR3 | |
1062 | EXCEPTION_LOAD_GPR4 | |
1063 | EXCEPTION_LOAD_GPR5 | |
1064 | EXCEPTION_LOAD_GPR6 | |
1065 | l.rfe | |
1066 | d_pmd_none: | |
1067 | d_pte_not_present: | |
1068 | EXCEPTION_LOAD_GPR2 | |
1069 | EXCEPTION_LOAD_GPR3 | |
1070 | EXCEPTION_LOAD_GPR4 | |
1071 | EXCEPTION_LOAD_GPR5 | |
1072 | EXCEPTION_LOAD_GPR6 | |
a81252d7 | 1073 | EXCEPTION_HANDLE(_dtlb_miss_page_fault_handler) |
9d02a428 JB |
1074 | |
1075 | /* ==============================================[ ITLB miss handler ]=== */ | |
1076 | ENTRY(itlb_miss_handler) | |
1077 | EXCEPTION_STORE_GPR2 | |
1078 | EXCEPTION_STORE_GPR3 | |
1079 | EXCEPTION_STORE_GPR4 | |
1080 | EXCEPTION_STORE_GPR5 | |
1081 | EXCEPTION_STORE_GPR6 | |
1082 | /* | |
1083 | * get EA of the miss | |
1084 | */ | |
1085 | l.mfspr r2,r0,SPR_EEAR_BASE | |
1086 | ||
1087 | /* | |
1088 | * pmd = (pmd_t *)(current_pgd + pgd_index(daddr)); | |
1089 | * | |
1090 | */ | |
1091 | GET_CURRENT_PGD(r3,r5) // r3 is current_pgd, r5 is temp | |
1092 | l.srli r4,r2,0x18 // >> PAGE_SHIFT + (PAGE_SHIFT - 2) | |
1093 | l.slli r4,r4,0x2 // to get address << 2 | |
1094 | l.add r5,r4,r3 // r4 is pgd_index(daddr) | |
1095 | /* | |
1096 | * if (pmd_none(*pmd)) | |
1097 | * goto pmd_none: | |
1098 | */ | |
1099 | tophys (r4,r5) | |
1100 | l.lwz r3,0x0(r4) // get *pmd value | |
1101 | l.sfne r3,r0 | |
1102 | l.bnf i_pmd_none | |
1103 | l.andi r3,r3,0x1fff // ~PAGE_MASK | |
1104 | /* | |
1105 | * if (pmd_bad(*pmd)) | |
1106 | * pmd_clear(pmd) | |
1107 | * goto pmd_bad: | |
1108 | */ | |
1109 | ||
1110 | // l.sfeq r3,r0 // check *pmd value | |
1111 | // l.bf i_pmd_good | |
1112 | l.addi r3,r0,0xffffe000 // PAGE_MASK | |
1113 | // l.j i_pmd_bad | |
1114 | // l.sw 0x0(r4),r0 // clear pmd | |
1115 | ||
1116 | i_pmd_good: | |
1117 | /* | |
1118 | * pte = *pte_offset(pmd, iaddr); | |
1119 | * | |
1120 | */ | |
1121 | l.lwz r4,0x0(r4) // get **pmd value | |
1122 | l.and r4,r4,r3 // & PAGE_MASK | |
1123 | l.srli r5,r2,0xd // >> PAGE_SHIFT, r2 == EEAR | |
1124 | l.andi r3,r5,0x7ff // (1UL << PAGE_SHIFT - 2) - 1 | |
1125 | l.slli r3,r3,0x2 // to get address << 2 | |
1126 | l.add r3,r3,r4 | |
1127 | l.lwz r2,0x0(r3) // this is pte at last | |
1128 | /* | |
1129 | * if (!pte_present(pte)) | |
1130 | * | |
1131 | */ | |
1132 | l.andi r4,r2,0x1 | |
1133 | l.sfne r4,r0 // is pte present | |
1134 | l.bnf i_pte_not_present | |
1135 | l.addi r3,r0,0xffffe03a // PAGE_MASK | ITLB_UP_CONVERT_MASK | |
1136 | /* | |
1137 | * fill ITLB TR register | |
1138 | */ | |
1139 | l.and r4,r2,r3 // apply the mask | |
1140 | l.andi r3,r2,0x7c0 // _PAGE_EXEC | _PAGE_SRE | _PAGE_SWE | _PAGE_URE | _PAGE_UWE | |
1141 | // l.andi r3,r2,0x400 // _PAGE_EXEC | |
1142 | l.sfeq r3,r0 | |
1143 | l.bf itlb_tr_fill //_workaround | |
1144 | // Determine number of IMMU sets | |
1145 | l.mfspr r6, r0, SPR_IMMUCFGR | |
1146 | l.andi r6, r6, SPR_IMMUCFGR_NTS | |
1147 | l.srli r6, r6, SPR_IMMUCFGR_NTS_OFF | |
1148 | l.ori r3, r0, 0x1 | |
1149 | l.sll r3, r3, r6 // r3 = number IMMU sets IMMUCFGR | |
1150 | l.addi r6, r3, -1 // r6 = nsets mask | |
1151 | l.and r5, r5, r6 // calc offset: & (NUM_TLB_ENTRIES-1) | |
1152 | ||
1153 | /* | |
1154 | * __PHX__ :: fixme | |
1155 | * we should not just blindly set executable flags, | |
1156 | * but it does help with ping. the clean way would be to find out | |
1157 | * (and fix it) why stack doesn't have execution permissions | |
1158 | */ | |
1159 | ||
1160 | itlb_tr_fill_workaround: | |
1161 | l.ori r4,r4,0xc0 // | (SPR_ITLBTR_UXE | ITLBTR_SXE) | |
1162 | itlb_tr_fill: | |
1163 | l.mtspr r5,r4,SPR_ITLBTR_BASE(0) | |
1164 | /* | |
1165 | * fill DTLB MR register | |
1166 | */ | |
1167 | l.mfspr r2,r0,SPR_EEAR_BASE | |
1168 | l.addi r3,r0,0xffffe000 // PAGE_MASK | |
1169 | l.and r4,r2,r3 // apply PAGE_MASK to EA (__PHX__ do we really need this?) | |
1170 | l.ori r4,r4,0x1 // set hardware valid bit: DTBL_MR entry | |
1171 | l.mtspr r5,r4,SPR_ITLBMR_BASE(0) | |
1172 | ||
1173 | EXCEPTION_LOAD_GPR2 | |
1174 | EXCEPTION_LOAD_GPR3 | |
1175 | EXCEPTION_LOAD_GPR4 | |
1176 | EXCEPTION_LOAD_GPR5 | |
1177 | EXCEPTION_LOAD_GPR6 | |
1178 | l.rfe | |
1179 | ||
1180 | i_pmd_bad: | |
1181 | l.nop 1 | |
1182 | EXCEPTION_LOAD_GPR2 | |
1183 | EXCEPTION_LOAD_GPR3 | |
1184 | EXCEPTION_LOAD_GPR4 | |
1185 | EXCEPTION_LOAD_GPR5 | |
1186 | EXCEPTION_LOAD_GPR6 | |
1187 | l.rfe | |
1188 | i_pmd_none: | |
1189 | i_pte_not_present: | |
1190 | EXCEPTION_LOAD_GPR2 | |
1191 | EXCEPTION_LOAD_GPR3 | |
1192 | EXCEPTION_LOAD_GPR4 | |
1193 | EXCEPTION_LOAD_GPR5 | |
1194 | EXCEPTION_LOAD_GPR6 | |
a81252d7 | 1195 | EXCEPTION_HANDLE(_itlb_miss_page_fault_handler) |
9d02a428 JB |
1196 | |
1197 | /* ==============================================[ boot tlb handlers ]=== */ | |
1198 | ||
1199 | ||
1200 | /* =================================================[ debugging aids ]=== */ | |
1201 | ||
1202 | .align 64 | |
1203 | _immu_trampoline: | |
1204 | .space 64 | |
1205 | _immu_trampoline_top: | |
1206 | ||
1207 | #define TRAMP_SLOT_0 (0x0) | |
1208 | #define TRAMP_SLOT_1 (0x4) | |
1209 | #define TRAMP_SLOT_2 (0x8) | |
1210 | #define TRAMP_SLOT_3 (0xc) | |
1211 | #define TRAMP_SLOT_4 (0x10) | |
1212 | #define TRAMP_SLOT_5 (0x14) | |
1213 | #define TRAMP_FRAME_SIZE (0x18) | |
1214 | ||
1215 | ENTRY(_immu_trampoline_workaround) | |
1216 | // r2 EEA | |
1217 | // r6 is physical EEA | |
1218 | tophys(r6,r2) | |
1219 | ||
1220 | LOAD_SYMBOL_2_GPR(r5,_immu_trampoline) | |
1221 | tophys (r3,r5) // r3 is trampoline (physical) | |
1222 | ||
1223 | LOAD_SYMBOL_2_GPR(r4,0x15000000) | |
1224 | l.sw TRAMP_SLOT_0(r3),r4 | |
1225 | l.sw TRAMP_SLOT_1(r3),r4 | |
1226 | l.sw TRAMP_SLOT_4(r3),r4 | |
1227 | l.sw TRAMP_SLOT_5(r3),r4 | |
1228 | ||
1229 | // EPC = EEA - 0x4 | |
1230 | l.lwz r4,0x0(r6) // load op @ EEA + 0x0 (fc address) | |
1231 | l.sw TRAMP_SLOT_3(r3),r4 // store it to _immu_trampoline_data | |
1232 | l.lwz r4,-0x4(r6) // load op @ EEA - 0x4 (f8 address) | |
1233 | l.sw TRAMP_SLOT_2(r3),r4 // store it to _immu_trampoline_data | |
1234 | ||
1235 | l.srli r5,r4,26 // check opcode for write access | |
1236 | l.sfeqi r5,0 // l.j | |
1237 | l.bf 0f | |
1238 | l.sfeqi r5,0x11 // l.jr | |
1239 | l.bf 1f | |
1240 | l.sfeqi r5,1 // l.jal | |
1241 | l.bf 2f | |
1242 | l.sfeqi r5,0x12 // l.jalr | |
1243 | l.bf 3f | |
1244 | l.sfeqi r5,3 // l.bnf | |
1245 | l.bf 4f | |
1246 | l.sfeqi r5,4 // l.bf | |
1247 | l.bf 5f | |
1248 | 99: | |
1249 | l.nop | |
1250 | l.j 99b // should never happen | |
1251 | l.nop 1 | |
1252 | ||
1253 | // r2 is EEA | |
1254 | // r3 is trampoline address (physical) | |
1255 | // r4 is instruction | |
1256 | // r6 is physical(EEA) | |
1257 | // | |
1258 | // r5 | |
1259 | ||
1260 | 2: // l.jal | |
1261 | ||
1262 | /* 19 20 aa aa l.movhi r9,0xaaaa | |
1263 | * a9 29 bb bb l.ori r9,0xbbbb | |
1264 | * | |
1265 | * where 0xaaaabbbb is EEA + 0x4 shifted right 2 | |
1266 | */ | |
1267 | ||
1268 | l.addi r6,r2,0x4 // this is 0xaaaabbbb | |
1269 | ||
1270 | // l.movhi r9,0xaaaa | |
1271 | l.ori r5,r0,0x1920 // 0x1920 == l.movhi r9 | |
1272 | l.sh (TRAMP_SLOT_0+0x0)(r3),r5 | |
1273 | l.srli r5,r6,16 | |
1274 | l.sh (TRAMP_SLOT_0+0x2)(r3),r5 | |
1275 | ||
1276 | // l.ori r9,0xbbbb | |
1277 | l.ori r5,r0,0xa929 // 0xa929 == l.ori r9 | |
1278 | l.sh (TRAMP_SLOT_1+0x0)(r3),r5 | |
1279 | l.andi r5,r6,0xffff | |
1280 | l.sh (TRAMP_SLOT_1+0x2)(r3),r5 | |
1281 | ||
1282 | /* falthrough, need to set up new jump offset */ | |
1283 | ||
1284 | ||
1285 | 0: // l.j | |
1286 | l.slli r6,r4,6 // original offset shifted left 6 - 2 | |
1287 | // l.srli r6,r6,6 // original offset shifted right 2 | |
1288 | ||
1289 | l.slli r4,r2,4 // old jump position: EEA shifted left 4 | |
1290 | // l.srli r4,r4,6 // old jump position: shifted right 2 | |
1291 | ||
1292 | l.addi r5,r3,0xc // new jump position (physical) | |
1293 | l.slli r5,r5,4 // new jump position: shifted left 4 | |
1294 | ||
1295 | // calculate new jump offset | |
1296 | // new_off = old_off + (old_jump - new_jump) | |
1297 | ||
1298 | l.sub r5,r4,r5 // old_jump - new_jump | |
1299 | l.add r5,r6,r5 // orig_off + (old_jump - new_jump) | |
1300 | l.srli r5,r5,6 // new offset shifted right 2 | |
1301 | ||
1302 | // r5 is new jump offset | |
1303 | // l.j has opcode 0x0... | |
1304 | l.sw TRAMP_SLOT_2(r3),r5 // write it back | |
1305 | ||
1306 | l.j trampoline_out | |
1307 | l.nop | |
1308 | ||
1309 | /* ----------------------------- */ | |
1310 | ||
1311 | 3: // l.jalr | |
1312 | ||
1313 | /* 19 20 aa aa l.movhi r9,0xaaaa | |
1314 | * a9 29 bb bb l.ori r9,0xbbbb | |
1315 | * | |
1316 | * where 0xaaaabbbb is EEA + 0x4 shifted right 2 | |
1317 | */ | |
1318 | ||
1319 | l.addi r6,r2,0x4 // this is 0xaaaabbbb | |
1320 | ||
1321 | // l.movhi r9,0xaaaa | |
1322 | l.ori r5,r0,0x1920 // 0x1920 == l.movhi r9 | |
1323 | l.sh (TRAMP_SLOT_0+0x0)(r3),r5 | |
1324 | l.srli r5,r6,16 | |
1325 | l.sh (TRAMP_SLOT_0+0x2)(r3),r5 | |
1326 | ||
1327 | // l.ori r9,0xbbbb | |
1328 | l.ori r5,r0,0xa929 // 0xa929 == l.ori r9 | |
1329 | l.sh (TRAMP_SLOT_1+0x0)(r3),r5 | |
1330 | l.andi r5,r6,0xffff | |
1331 | l.sh (TRAMP_SLOT_1+0x2)(r3),r5 | |
1332 | ||
1333 | l.lhz r5,(TRAMP_SLOT_2+0x0)(r3) // load hi part of jump instruction | |
1334 | l.andi r5,r5,0x3ff // clear out opcode part | |
1335 | l.ori r5,r5,0x4400 // opcode changed from l.jalr -> l.jr | |
1336 | l.sh (TRAMP_SLOT_2+0x0)(r3),r5 // write it back | |
1337 | ||
1338 | /* falthrough */ | |
1339 | ||
1340 | 1: // l.jr | |
1341 | l.j trampoline_out | |
1342 | l.nop | |
1343 | ||
1344 | /* ----------------------------- */ | |
1345 | ||
1346 | 4: // l.bnf | |
1347 | 5: // l.bf | |
1348 | l.slli r6,r4,6 // original offset shifted left 6 - 2 | |
1349 | // l.srli r6,r6,6 // original offset shifted right 2 | |
1350 | ||
1351 | l.slli r4,r2,4 // old jump position: EEA shifted left 4 | |
1352 | // l.srli r4,r4,6 // old jump position: shifted right 2 | |
1353 | ||
1354 | l.addi r5,r3,0xc // new jump position (physical) | |
1355 | l.slli r5,r5,4 // new jump position: shifted left 4 | |
1356 | ||
1357 | // calculate new jump offset | |
1358 | // new_off = old_off + (old_jump - new_jump) | |
1359 | ||
1360 | l.add r6,r6,r4 // (orig_off + old_jump) | |
1361 | l.sub r6,r6,r5 // (orig_off + old_jump) - new_jump | |
1362 | l.srli r6,r6,6 // new offset shifted right 2 | |
1363 | ||
1364 | // r6 is new jump offset | |
1365 | l.lwz r4,(TRAMP_SLOT_2+0x0)(r3) // load jump instruction | |
1366 | l.srli r4,r4,16 | |
1367 | l.andi r4,r4,0xfc00 // get opcode part | |
1368 | l.slli r4,r4,16 | |
1369 | l.or r6,r4,r6 // l.b(n)f new offset | |
1370 | l.sw TRAMP_SLOT_2(r3),r6 // write it back | |
1371 | ||
1372 | /* we need to add l.j to EEA + 0x8 */ | |
1373 | tophys (r4,r2) // may not be needed (due to shifts down_ | |
1374 | l.addi r4,r4,(0x8 - 0x8) // jump target = r2 + 0x8 (compensate for 0x8) | |
1375 | // jump position = r5 + 0x8 (0x8 compensated) | |
1376 | l.sub r4,r4,r5 // jump offset = target - new_position + 0x8 | |
1377 | ||
1378 | l.slli r4,r4,4 // the amount of info in imediate of jump | |
1379 | l.srli r4,r4,6 // jump instruction with offset | |
1380 | l.sw TRAMP_SLOT_4(r3),r4 // write it to 4th slot | |
1381 | ||
1382 | /* fallthrough */ | |
1383 | ||
1384 | trampoline_out: | |
1385 | // set up new EPC to point to our trampoline code | |
1386 | LOAD_SYMBOL_2_GPR(r5,_immu_trampoline) | |
1387 | l.mtspr r0,r5,SPR_EPCR_BASE | |
1388 | ||
1389 | // immu_trampoline is (4x) CACHE_LINE aligned | |
1390 | // and only 6 instructions long, | |
1391 | // so we need to invalidate only 2 lines | |
1392 | ||
1393 | /* Establish cache block size | |
1394 | If BS=0, 16; | |
1395 | If BS=1, 32; | |
1396 | r14 contain block size | |
1397 | */ | |
1398 | l.mfspr r21,r0,SPR_ICCFGR | |
1399 | l.andi r21,r21,SPR_ICCFGR_CBS | |
1400 | l.srli r21,r21,7 | |
1401 | l.ori r23,r0,16 | |
1402 | l.sll r14,r23,r21 | |
1403 | ||
1404 | l.mtspr r0,r5,SPR_ICBIR | |
1405 | l.add r5,r5,r14 | |
1406 | l.mtspr r0,r5,SPR_ICBIR | |
1407 | ||
1408 | l.jr r9 | |
1409 | l.nop | |
1410 | ||
1411 | ||
1412 | /* | |
1413 | * DSCR: prints a string referenced by r3. | |
1414 | * | |
1415 | * PRMS: r3 - address of the first character of null | |
1416 | * terminated string to be printed | |
1417 | * | |
1418 | * PREQ: UART at UART_BASE_ADD has to be initialized | |
1419 | * | |
1420 | * POST: caller should be aware that r3, r9 are changed | |
1421 | */ | |
1422 | ENTRY(_emergency_print) | |
1423 | EMERGENCY_PRINT_STORE_GPR4 | |
1424 | EMERGENCY_PRINT_STORE_GPR5 | |
1425 | EMERGENCY_PRINT_STORE_GPR6 | |
1426 | EMERGENCY_PRINT_STORE_GPR7 | |
1427 | 2: | |
1428 | l.lbz r7,0(r3) | |
1429 | l.sfeq r7,r0 | |
1430 | l.bf 9f | |
1431 | l.nop | |
1432 | ||
1433 | // putc: | |
1434 | l.movhi r4,hi(UART_BASE_ADD) | |
1435 | ||
1436 | l.addi r6,r0,0x20 | |
1437 | 1: l.lbz r5,5(r4) | |
1438 | l.andi r5,r5,0x20 | |
1439 | l.sfeq r5,r6 | |
1440 | l.bnf 1b | |
1441 | l.nop | |
1442 | ||
1443 | l.sb 0(r4),r7 | |
1444 | ||
1445 | l.addi r6,r0,0x60 | |
1446 | 1: l.lbz r5,5(r4) | |
1447 | l.andi r5,r5,0x60 | |
1448 | l.sfeq r5,r6 | |
1449 | l.bnf 1b | |
1450 | l.nop | |
1451 | ||
1452 | /* next character */ | |
1453 | l.j 2b | |
1454 | l.addi r3,r3,0x1 | |
1455 | ||
1456 | 9: | |
1457 | EMERGENCY_PRINT_LOAD_GPR7 | |
1458 | EMERGENCY_PRINT_LOAD_GPR6 | |
1459 | EMERGENCY_PRINT_LOAD_GPR5 | |
1460 | EMERGENCY_PRINT_LOAD_GPR4 | |
1461 | l.jr r9 | |
1462 | l.nop | |
1463 | ||
1464 | ENTRY(_emergency_print_nr) | |
1465 | EMERGENCY_PRINT_STORE_GPR4 | |
1466 | EMERGENCY_PRINT_STORE_GPR5 | |
1467 | EMERGENCY_PRINT_STORE_GPR6 | |
1468 | EMERGENCY_PRINT_STORE_GPR7 | |
1469 | EMERGENCY_PRINT_STORE_GPR8 | |
1470 | ||
1471 | l.addi r8,r0,32 // shift register | |
1472 | ||
1473 | 1: /* remove leading zeros */ | |
1474 | l.addi r8,r8,-0x4 | |
1475 | l.srl r7,r3,r8 | |
1476 | l.andi r7,r7,0xf | |
1477 | ||
1478 | /* don't skip the last zero if number == 0x0 */ | |
1479 | l.sfeqi r8,0x4 | |
1480 | l.bf 2f | |
1481 | l.nop | |
1482 | ||
1483 | l.sfeq r7,r0 | |
1484 | l.bf 1b | |
1485 | l.nop | |
1486 | ||
1487 | 2: | |
1488 | l.srl r7,r3,r8 | |
1489 | ||
1490 | l.andi r7,r7,0xf | |
1491 | l.sflts r8,r0 | |
1492 | l.bf 9f | |
1493 | ||
1494 | l.sfgtui r7,0x9 | |
1495 | l.bnf 8f | |
1496 | l.nop | |
1497 | l.addi r7,r7,0x27 | |
1498 | ||
1499 | 8: | |
1500 | l.addi r7,r7,0x30 | |
1501 | // putc: | |
1502 | l.movhi r4,hi(UART_BASE_ADD) | |
1503 | ||
1504 | l.addi r6,r0,0x20 | |
1505 | 1: l.lbz r5,5(r4) | |
1506 | l.andi r5,r5,0x20 | |
1507 | l.sfeq r5,r6 | |
1508 | l.bnf 1b | |
1509 | l.nop | |
1510 | ||
1511 | l.sb 0(r4),r7 | |
1512 | ||
1513 | l.addi r6,r0,0x60 | |
1514 | 1: l.lbz r5,5(r4) | |
1515 | l.andi r5,r5,0x60 | |
1516 | l.sfeq r5,r6 | |
1517 | l.bnf 1b | |
1518 | l.nop | |
1519 | ||
1520 | /* next character */ | |
1521 | l.j 2b | |
1522 | l.addi r8,r8,-0x4 | |
1523 | ||
1524 | 9: | |
1525 | EMERGENCY_PRINT_LOAD_GPR8 | |
1526 | EMERGENCY_PRINT_LOAD_GPR7 | |
1527 | EMERGENCY_PRINT_LOAD_GPR6 | |
1528 | EMERGENCY_PRINT_LOAD_GPR5 | |
1529 | EMERGENCY_PRINT_LOAD_GPR4 | |
1530 | l.jr r9 | |
1531 | l.nop | |
1532 | ||
1533 | ||
1534 | /* | |
1535 | * This should be used for debugging only. | |
1536 | * It messes up the Linux early serial output | |
1537 | * somehow, so use it sparingly and essentially | |
1538 | * only if you need to debug something that goes wrong | |
1539 | * before Linux gets the early serial going. | |
1540 | * | |
1541 | * Furthermore, you'll have to make sure you set the | |
1542 | * UART_DEVISOR correctly according to the system | |
1543 | * clock rate. | |
1544 | * | |
1545 | * | |
1546 | */ | |
1547 | ||
1548 | ||
1549 | ||
1550 | #define SYS_CLK 20000000 | |
1551 | //#define SYS_CLK 1843200 | |
1552 | #define OR32_CONSOLE_BAUD 115200 | |
1553 | #define UART_DIVISOR SYS_CLK/(16*OR32_CONSOLE_BAUD) | |
1554 | ||
1555 | ENTRY(_early_uart_init) | |
1556 | l.movhi r3,hi(UART_BASE_ADD) | |
1557 | ||
1558 | l.addi r4,r0,0x7 | |
1559 | l.sb 0x2(r3),r4 | |
1560 | ||
1561 | l.addi r4,r0,0x0 | |
1562 | l.sb 0x1(r3),r4 | |
1563 | ||
1564 | l.addi r4,r0,0x3 | |
1565 | l.sb 0x3(r3),r4 | |
1566 | ||
1567 | l.lbz r5,3(r3) | |
1568 | l.ori r4,r5,0x80 | |
1569 | l.sb 0x3(r3),r4 | |
1570 | l.addi r4,r0,((UART_DIVISOR>>8) & 0x000000ff) | |
1571 | l.sb UART_DLM(r3),r4 | |
1572 | l.addi r4,r0,((UART_DIVISOR) & 0x000000ff) | |
1573 | l.sb UART_DLL(r3),r4 | |
1574 | l.sb 0x3(r3),r5 | |
1575 | ||
1576 | l.jr r9 | |
1577 | l.nop | |
1578 | ||
1579 | _string_copying_linux: | |
1580 | .string "\n\n\n\n\n\rCopying Linux... \0" | |
1581 | ||
1582 | _string_ok_booting: | |
1583 | .string "Ok, booting the kernel.\n\r\0" | |
1584 | ||
1585 | _string_unhandled_exception: | |
1586 | .string "\n\rRunarunaround: Unhandled exception 0x\0" | |
1587 | ||
1588 | _string_epc_prefix: | |
1589 | .string ": EPC=0x\0" | |
1590 | ||
1591 | _string_nl: | |
1592 | .string "\n\r\0" | |
1593 | ||
1594 | .global _string_esr_irq_bug | |
1595 | _string_esr_irq_bug: | |
1596 | .string "\n\rESR external interrupt bug, for details look into entry.S\n\r\0" | |
1597 | ||
1598 | ||
1599 | ||
1600 | /* ========================================[ page aligned structures ]=== */ | |
1601 | ||
1602 | /* | |
1603 | * .data section should be page aligned | |
1604 | * (look into arch/or32/kernel/vmlinux.lds) | |
1605 | */ | |
1606 | .section .data,"aw" | |
1607 | .align 8192 | |
1608 | .global empty_zero_page | |
1609 | empty_zero_page: | |
1610 | .space 8192 | |
1611 | ||
1612 | .global swapper_pg_dir | |
1613 | swapper_pg_dir: | |
1614 | .space 8192 | |
1615 | ||
1616 | .global _unhandled_stack | |
1617 | _unhandled_stack: | |
1618 | .space 8192 | |
1619 | _unhandled_stack_top: | |
1620 | ||
1621 | /* ============================================================[ EOF ]=== */ |