1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __HEAD_BOOKE_H__
3 #define __HEAD_BOOKE_H__
5 #include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */
6 #include <asm/kvm_asm.h>
7 #include <asm/kvm_booke_hv_asm.h>
12 * Macros used for common Book-e exception handling
15 #define SET_IVOR(vector_number, vector_label) \
16 li r26,vector_label@l; \
17 mtspr SPRN_IVOR##vector_number,r26; \
20 #if (THREAD_SHIFT < 15)
21 #define ALLOC_STACK_FRAME(reg, val) \
24 #define ALLOC_STACK_FRAME(reg, val) \
25 addis reg,reg,val@ha; \
30 * Macro used to get to thread save registers.
31 * Note that entries 0-3 are used for the prolog code, and the remaining
32 * entries are available for specific exception use in the event a handler
33 * requires more than 4 scratch registers.
35 #define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4))
37 #ifdef CONFIG_PPC_FSL_BOOK3E
38 #define BOOKE_CLEAR_BTB(reg) \
39 START_BTB_FLUSH_SECTION \
43 #define BOOKE_CLEAR_BTB(reg)
47 #define NORMAL_EXCEPTION_PROLOG(intno) \
48 mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
49 mfspr r10, SPRN_SPRG_THREAD; \
50 stw r11, THREAD_NORMSAVE(0)(r10); \
51 stw r13, THREAD_NORMSAVE(2)(r10); \
52 mfcr r13; /* save CR in r13 for now */\
53 mfspr r11, SPRN_SRR1; \
54 DO_KVM BOOKE_INTERRUPT_##intno SPRN_SRR1; \
55 andi. r11, r11, MSR_PR; /* check whether user or kernel */\
58 BOOKE_CLEAR_BTB(r11) \
59 /* if from user, start at top of this thread's kernel stack */ \
60 lwz r11, TASK_STACK - THREAD(r10); \
61 ALLOC_STACK_FRAME(r11, THREAD_SIZE); \
62 1 : subi r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */ \
63 stw r13, _CCR(r11); /* save various registers */ \
66 mfspr r13, SPRN_SPRG_RSCRATCH0; \
67 stw r13, GPR10(r11); \
68 lwz r12, THREAD_NORMSAVE(0)(r10); \
70 lwz r13, THREAD_NORMSAVE(2)(r10); /* restore r13 */ \
73 mfspr r12,SPRN_SRR0; \
78 rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
80 lis r10, STACK_FRAME_REGS_MARKER@ha;/* exception frame marker */ \
81 addi r10, r10, STACK_FRAME_REGS_MARKER@l; \
86 .macro SYSCALL_ENTRY trapno intno srr1
87 mfspr r10
, SPRN_SPRG_THREAD
88 #ifdef CONFIG_KVM_BOOKE_HV
90 mtspr SPRN_SPRG_WSCRATCH0
, r10
91 stw r11
, THREAD_NORMSAVE(0)(r10
)
92 stw r13
, THREAD_NORMSAVE(2)(r10
)
93 mfcr r13
/* save CR in r13 for now */
95 mtocrf
0x80, r11
/* check MSR[GS] without clobbering reg */
97 b kvmppc_handler_\intno\
()_\srr1
100 lwz r13
, THREAD_NORMSAVE(2)(r10
)
104 #ifdef CONFIG_KVM_BOOKE_HV
105 ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV
)
108 lwz r11
, TASK_STACK
- THREAD(r10
)
109 rlwinm r12
,r12
,0,4,2 /* Clear SO bit in CR */
110 ALLOC_STACK_FRAME(r11
, THREAD_SIZE
- INT_FRAME_SIZE
)
111 stw r12
, _CCR(r11
) /* save various registers */
120 rlwinm r9
,r9
,0,14,12 /* clear MSR_WE (necessary?) */
121 lis r12
, STACK_FRAME_REGS_MARKER@ha
/* exception frame marker */
123 addi r12
, r12
, STACK_FRAME_REGS_MARKER@l
132 addi r11
,r1
,STACK_FRAME_OVERHEAD
135 /* Check to see if the dbcr0 register is set up to debug. Use the
136 internal debug mode bit to do this. */
137 lwz r12
,THREAD_DBCR0(r10
)
138 andis
. r12
,r12
,DBCR0_IDM@h
139 ACCOUNT_CPU_USER_ENTRY(r2
, r11
, r12
)
141 /* From user and task is ptraced - load up global dbcr0 */
142 li r12
,-1 /* clear all pending debug events */
144 lis r11
,global_dbcr0@ha
146 addi r11
,r11
,global_dbcr0@l
148 lwz r10
, TASK_CPU(r2
)
159 tovirt(r2
, r2
) /* set r2 to current */
160 lis r11
, transfer_to_syscall@h
161 ori r11
, r11
, transfer_to_syscall@l
162 #ifdef CONFIG_TRACE_IRQFLAGS
164 * If MSR is changing we need to keep interrupts disabled at this point
165 * otherwise we might risk taking an interrupt before we tell lockdep
168 lis r10
, MSR_KERNEL@h
169 ori r10
, r10
, MSR_KERNEL@l
170 rlwimi r10
, r9
, 0, MSR_EE
172 lis r10
, (MSR_KERNEL
| MSR_EE
)@h
173 ori r10
, r10
, (MSR_KERNEL
| MSR_EE
)@l
178 RFI
/* jump to handler, enable MMU */
181 /* To handle the additional exception priority levels on 40x and Book-E
182 * processors we allocate a stack per additional priority level.
184 * On 40x critical is the only additional level
185 * On 44x/e500 we have critical and machine check
186 * On e200 we have critical and debug (machine check occurs via critical)
188 * Additionally we reserve a SPRG for each priority level so we can free up a
189 * GPR to use as the base for indirect access to the exception stacks. This
190 * is necessary since the MMU is always on, for Book-E parts, and the stacks
191 * are offset from KERNELBASE.
193 * There is some space optimization to be had here if desired. However
194 * to allow for a common kernel with support for debug exceptions either
195 * going to critical or their own debug level we aren't currently
196 * providing configurations that micro-optimize space usage.
199 #define MC_STACK_BASE mcheckirq_ctx
200 #define CRIT_STACK_BASE critirq_ctx
202 /* only on e500mc/e200 */
203 #define DBG_STACK_BASE dbgirq_ctx
205 #define EXC_LVL_FRAME_OVERHEAD (THREAD_SIZE - INT_FRAME_SIZE - EXC_LVL_SIZE)
208 #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
211 addis r8,r8,level##_STACK_BASE@ha; \
212 lwz r8,level##_STACK_BASE@l(r8); \
213 addi r8,r8,EXC_LVL_FRAME_OVERHEAD;
215 #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
216 lis r8,level##_STACK_BASE@ha; \
217 lwz r8,level##_STACK_BASE@l(r8); \
218 addi r8,r8,EXC_LVL_FRAME_OVERHEAD;
222 * Exception prolog for critical/machine check exceptions. This is a
223 * little different from the normal exception prolog above since a
224 * critical/machine check exception can potentially occur at any point
225 * during normal exception processing. Thus we cannot use the same SPRG
226 * registers as the normal prolog above. Instead we use a portion of the
227 * critical/machine check exception stack at low physical addresses.
229 #define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, intno, exc_level_srr0, exc_level_srr1) \
230 mtspr SPRN_SPRG_WSCRATCH_##exc_level,r8; \
231 BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \
232 stw r9,GPR9(r8); /* save various registers */\
233 mfcr r9; /* save CR in r9 for now */\
236 stw r9,_CCR(r8); /* save CR on stack */\
237 mfspr r11,exc_level_srr1; /* check whether user or kernel */\
238 DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \
239 BOOKE_CLEAR_BTB(r10) \
240 andi. r11,r11,MSR_PR; \
241 mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\
242 lwz r11, TASK_STACK - THREAD(r11); /* this thread's kernel stack */\
243 addi r11,r11,EXC_LVL_FRAME_OVERHEAD; /* allocate stack frame */\
245 /* COMING FROM USER MODE */ \
246 stw r9,_CCR(r11); /* save CR */\
247 lwz r10,GPR10(r8); /* copy regs from exception stack */\
249 stw r10,GPR10(r11); \
252 stw r10,GPR11(r11); \
254 /* COMING FROM PRIV MODE */ \
256 2: mfspr r8,SPRN_SPRG_RSCRATCH_##exc_level; \
257 stw r12,GPR12(r11); /* save various registers */\
259 stw r10,_LINK(r11); \
260 mfspr r12,SPRN_DEAR; /* save DEAR and ESR in the frame */\
261 stw r12,_DEAR(r11); /* since they may have had stuff */\
262 mfspr r9,SPRN_ESR; /* in them at the point where the */\
263 stw r9,_ESR(r11); /* exception was taken */\
264 mfspr r12,exc_level_srr0; \
266 mfspr r9,exc_level_srr1; \
269 rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
271 SAVE_4GPRS(3, r11); \
274 #define CRITICAL_EXCEPTION_PROLOG(intno) \
275 EXC_LEVEL_EXCEPTION_PROLOG(CRIT, intno, SPRN_CSRR0, SPRN_CSRR1)
276 #define DEBUG_EXCEPTION_PROLOG \
277 EXC_LEVEL_EXCEPTION_PROLOG(DBG, DEBUG, SPRN_DSRR0, SPRN_DSRR1)
278 #define MCHECK_EXCEPTION_PROLOG \
279 EXC_LEVEL_EXCEPTION_PROLOG(MC, MACHINE_CHECK, \
280 SPRN_MCSRR0, SPRN_MCSRR1)
283 * Guest Doorbell -- this is a bit odd in that uses GSRR0/1 despite
284 * being delivered to the host. This exception can only happen
285 * inside a KVM guest -- so we just handle up to the DO_KVM rather
286 * than try to fit this into one of the existing prolog macros.
288 #define GUEST_DOORBELL_EXCEPTION \
289 START_EXCEPTION(GuestDoorbell); \
290 mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
291 mfspr r10, SPRN_SPRG_THREAD; \
292 stw r11, THREAD_NORMSAVE(0)(r10); \
293 mfspr r11, SPRN_SRR1; \
294 stw r13, THREAD_NORMSAVE(2)(r10); \
295 mfcr r13; /* save CR in r13 for now */\
296 DO_KVM BOOKE_INTERRUPT_GUEST_DBELL SPRN_GSRR1; \
302 #define START_EXCEPTION(label) \
306 #define EXCEPTION(n, intno, label, hdlr, xfer) \
307 START_EXCEPTION(label); \
308 NORMAL_EXCEPTION_PROLOG(intno); \
309 addi r3,r1,STACK_FRAME_OVERHEAD; \
312 #define CRITICAL_EXCEPTION(n, intno, label, hdlr) \
313 START_EXCEPTION(label); \
314 CRITICAL_EXCEPTION_PROLOG(intno); \
315 addi r3,r1,STACK_FRAME_OVERHEAD; \
316 EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
317 crit_transfer_to_handler, ret_from_crit_exc)
319 #define MCHECK_EXCEPTION(n, label, hdlr) \
320 START_EXCEPTION(label); \
321 MCHECK_EXCEPTION_PROLOG; \
324 addi r3,r1,STACK_FRAME_OVERHEAD; \
325 EXC_XFER_TEMPLATE(hdlr, n+4, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
326 mcheck_transfer_to_handler, ret_from_mcheck_exc)
328 #define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \
330 stw r10,_TRAP(r11); \
337 #define EXC_XFER_STD(n, hdlr) \
338 EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full, \
339 ret_from_except_full)
341 #define EXC_XFER_LITE(n, hdlr) \
342 EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \
345 /* Check for a single step debug exception while in an exception
346 * handler before state has been saved. This is to catch the case
347 * where an instruction that we are trying to single step causes
348 * an exception (eg ITLB/DTLB miss) and thus the first instruction of
349 * the exception handler generates a single step debug exception.
351 * If we get a debug trap on the first instruction of an exception handler,
352 * we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is
353 * a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR).
354 * The exception handler was handling a non-critical interrupt, so it will
355 * save (and later restore) the MSR via SPRN_CSRR1, which will still have
356 * the MSR_DE bit set.
358 #define DEBUG_DEBUG_EXCEPTION \
359 START_EXCEPTION(DebugDebug); \
360 DEBUG_EXCEPTION_PROLOG; \
363 * If there is a single step or branch-taken exception in an \
364 * exception entry sequence, it was probably meant to apply to \
365 * the code where the exception occurred (since exception entry \
366 * doesn't turn off DE automatically). We simulate the effect \
367 * of turning off DE on entry to an exception handler by turning \
368 * off DE in the DSRR1 value and clearing the debug status. \
370 mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
371 andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
374 lis r10,interrupt_base@h; /* check if exception in vectors */ \
375 ori r10,r10,interrupt_base@l; \
377 blt+ 2f; /* addr below exception vectors */ \
379 lis r10,interrupt_end@h; \
380 ori r10,r10,interrupt_end@l; \
382 bgt+ 2f; /* addr above exception vectors */ \
384 /* here it looks like we got an inappropriate debug exception. */ \
385 1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CDRR1 value */ \
386 lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
387 mtspr SPRN_DBSR,r10; \
388 /* restore state and get out */ \
393 mtspr SPRN_DSRR0,r12; \
394 mtspr SPRN_DSRR1,r9; \
396 lwz r12,GPR12(r11); \
397 mtspr SPRN_SPRG_WSCRATCH_DBG,r8; \
398 BOOKE_LOAD_EXC_LEVEL_STACK(DBG); /* r8 points to the debug stack */ \
401 mfspr r8,SPRN_SPRG_RSCRATCH_DBG; \
406 /* continue normal handling for a debug exception... */ \
407 2: mfspr r4,SPRN_DBSR; \
408 addi r3,r1,STACK_FRAME_OVERHEAD; \
409 EXC_XFER_TEMPLATE(DebugException, 0x2008, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), debug_transfer_to_handler, ret_from_debug_exc)
411 #define DEBUG_CRIT_EXCEPTION \
412 START_EXCEPTION(DebugCrit); \
413 CRITICAL_EXCEPTION_PROLOG(DEBUG); \
416 * If there is a single step or branch-taken exception in an \
417 * exception entry sequence, it was probably meant to apply to \
418 * the code where the exception occurred (since exception entry \
419 * doesn't turn off DE automatically). We simulate the effect \
420 * of turning off DE on entry to an exception handler by turning \
421 * off DE in the CSRR1 value and clearing the debug status. \
423 mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
424 andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
427 lis r10,interrupt_base@h; /* check if exception in vectors */ \
428 ori r10,r10,interrupt_base@l; \
430 blt+ 2f; /* addr below exception vectors */ \
432 lis r10,interrupt_end@h; \
433 ori r10,r10,interrupt_end@l; \
435 bgt+ 2f; /* addr above exception vectors */ \
437 /* here it looks like we got an inappropriate debug exception. */ \
438 1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CSRR1 value */ \
439 lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
440 mtspr SPRN_DBSR,r10; \
441 /* restore state and get out */ \
446 mtspr SPRN_CSRR0,r12; \
447 mtspr SPRN_CSRR1,r9; \
449 lwz r12,GPR12(r11); \
450 mtspr SPRN_SPRG_WSCRATCH_CRIT,r8; \
451 BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */ \
454 mfspr r8,SPRN_SPRG_RSCRATCH_CRIT; \
459 /* continue normal handling for a critical exception... */ \
460 2: mfspr r4,SPRN_DBSR; \
461 addi r3,r1,STACK_FRAME_OVERHEAD; \
462 EXC_XFER_TEMPLATE(DebugException, 0x2002, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), crit_transfer_to_handler, ret_from_crit_exc)
464 #define DATA_STORAGE_EXCEPTION \
465 START_EXCEPTION(DataStorage) \
466 NORMAL_EXCEPTION_PROLOG(DATA_STORAGE); \
467 mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
469 mfspr r4,SPRN_DEAR; /* Grab the DEAR */ \
470 stw r4, _DEAR(r11); \
471 EXC_XFER_LITE(0x0300, handle_page_fault)
473 #define INSTRUCTION_STORAGE_EXCEPTION \
474 START_EXCEPTION(InstructionStorage) \
475 NORMAL_EXCEPTION_PROLOG(INST_STORAGE); \
476 mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
478 mr r4,r12; /* Pass SRR0 as arg2 */ \
479 stw r4, _DEAR(r11); \
480 li r5,0; /* Pass zero as arg3 */ \
481 EXC_XFER_LITE(0x0400, handle_page_fault)
483 #define ALIGNMENT_EXCEPTION \
484 START_EXCEPTION(Alignment) \
485 NORMAL_EXCEPTION_PROLOG(ALIGNMENT); \
486 mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \
488 addi r3,r1,STACK_FRAME_OVERHEAD; \
489 EXC_XFER_STD(0x0600, alignment_exception)
491 #define PROGRAM_EXCEPTION \
492 START_EXCEPTION(Program) \
493 NORMAL_EXCEPTION_PROLOG(PROGRAM); \
494 mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \
496 addi r3,r1,STACK_FRAME_OVERHEAD; \
497 EXC_XFER_STD(0x0700, program_check_exception)
499 #define DECREMENTER_EXCEPTION \
500 START_EXCEPTION(Decrementer) \
501 NORMAL_EXCEPTION_PROLOG(DECREMENTER); \
502 lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \
503 mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \
504 addi r3,r1,STACK_FRAME_OVERHEAD; \
505 EXC_XFER_LITE(0x0900, timer_interrupt)
507 #define FP_UNAVAILABLE_EXCEPTION \
508 START_EXCEPTION(FloatingPointUnavailable) \
509 NORMAL_EXCEPTION_PROLOG(FP_UNAVAIL); \
511 bl load_up_fpu; /* if from user, just load it up */ \
512 b fast_exception_return; \
513 1: addi r3,r1,STACK_FRAME_OVERHEAD; \
514 EXC_XFER_STD(0x800, kernel_fp_unavailable_exception)
516 #else /* __ASSEMBLY__ */
517 struct exception_regs
{
530 unsigned long saved_ksp_limit
;
533 /* ensure this structure is always sized to a multiple of the stack alignment */
534 #define STACK_EXC_LVL_FRAME_SIZE _ALIGN_UP(sizeof (struct exception_regs), 16)
536 #endif /* __ASSEMBLY__ */
537 #endif /* __HEAD_BOOKE_H__ */