1 #ifndef __HEAD_BOOKE_H__
2 #define __HEAD_BOOKE_H__
4 #include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */
5 #include <asm/kvm_asm.h>
6 #include <asm/kvm_booke_hv_asm.h>
9 * Macros used for common Book-e exception handling
12 #define SET_IVOR(vector_number, vector_label) \
13 li r26,vector_label@l; \
14 mtspr SPRN_IVOR##vector_number,r26; \
17 #if (THREAD_SHIFT < 15)
18 #define ALLOC_STACK_FRAME(reg, val) \
21 #define ALLOC_STACK_FRAME(reg, val) \
22 addis reg,reg,val@ha; \
27 * Macro used to get to thread save registers.
28 * Note that entries 0-3 are used for the prolog code, and the remaining
29 * entries are available for specific exception use in the event a handler
30 * requires more than 4 scratch registers.
32 #define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4))
34 #define NORMAL_EXCEPTION_PROLOG(intno) \
35 mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
36 mfspr r10, SPRN_SPRG_THREAD; \
37 stw r11, THREAD_NORMSAVE(0)(r10); \
38 stw r13, THREAD_NORMSAVE(2)(r10); \
39 mfcr r13; /* save CR in r13 for now */\
40 mfspr r11, SPRN_SRR1; \
41 DO_KVM BOOKE_INTERRUPT_##intno SPRN_SRR1; \
42 andi. r11, r11, MSR_PR; /* check whether user or kernel */\
45 /* if from user, start at top of this thread's kernel stack */ \
46 lwz r11, THREAD_INFO-THREAD(r10); \
47 ALLOC_STACK_FRAME(r11, THREAD_SIZE); \
48 1 : subi r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */ \
49 stw r13, _CCR(r11); /* save various registers */ \
52 mfspr r13, SPRN_SPRG_RSCRATCH0; \
53 stw r13, GPR10(r11); \
54 lwz r12, THREAD_NORMSAVE(0)(r10); \
56 lwz r13, THREAD_NORMSAVE(2)(r10); /* restore r13 */ \
59 mfspr r12,SPRN_SRR0; \
64 rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
66 lis r10, STACK_FRAME_REGS_MARKER@ha;/* exception frame marker */ \
67 addi r10, r10, STACK_FRAME_REGS_MARKER@l; \
72 /* To handle the additional exception priority levels on 40x and Book-E
73 * processors we allocate a stack per additional priority level.
75 * On 40x critical is the only additional level
76 * On 44x/e500 we have critical and machine check
77 * On e200 we have critical and debug (machine check occurs via critical)
79 * Additionally we reserve a SPRG for each priority level so we can free up a
80 * GPR to use as the base for indirect access to the exception stacks. This
81 * is necessary since the MMU is always on, for Book-E parts, and the stacks
82 * are offset from KERNELBASE.
84 * There is some space optimization to be had here if desired. However
85 * to allow for a common kernel with support for debug exceptions either
86 * going to critical or their own debug level we aren't currently
87 * providing configurations that micro-optimize space usage.
90 #define MC_STACK_BASE mcheckirq_ctx
91 #define CRIT_STACK_BASE critirq_ctx
93 /* only on e500mc/e200 */
94 #define DBG_STACK_BASE dbgirq_ctx
96 #define EXC_LVL_FRAME_OVERHEAD (THREAD_SIZE - INT_FRAME_SIZE - EXC_LVL_SIZE)
99 #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
102 addis r8,r8,level##_STACK_BASE@ha; \
103 lwz r8,level##_STACK_BASE@l(r8); \
104 addi r8,r8,EXC_LVL_FRAME_OVERHEAD;
106 #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
107 lis r8,level##_STACK_BASE@ha; \
108 lwz r8,level##_STACK_BASE@l(r8); \
109 addi r8,r8,EXC_LVL_FRAME_OVERHEAD;
113 * Exception prolog for critical/machine check exceptions. This is a
114 * little different from the normal exception prolog above since a
115 * critical/machine check exception can potentially occur at any point
116 * during normal exception processing. Thus we cannot use the same SPRG
117 * registers as the normal prolog above. Instead we use a portion of the
118 * critical/machine check exception stack at low physical addresses.
120 #define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, intno, exc_level_srr0, exc_level_srr1) \
121 mtspr SPRN_SPRG_WSCRATCH_##exc_level,r8; \
122 BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \
123 stw r9,GPR9(r8); /* save various registers */\
124 mfcr r9; /* save CR in r9 for now */\
127 stw r9,_CCR(r8); /* save CR on stack */\
128 mfspr r11,exc_level_srr1; /* check whether user or kernel */\
129 DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \
130 andi. r11,r11,MSR_PR; \
131 mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\
132 lwz r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
133 addi r11,r11,EXC_LVL_FRAME_OVERHEAD; /* allocate stack frame */\
135 /* COMING FROM USER MODE */ \
136 stw r9,_CCR(r11); /* save CR */\
137 lwz r10,GPR10(r8); /* copy regs from exception stack */\
139 stw r10,GPR10(r11); \
142 stw r10,GPR11(r11); \
144 /* COMING FROM PRIV MODE */ \
145 1: lwz r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r11); \
146 lwz r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r11); \
147 stw r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r8); \
148 stw r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r8); \
149 lwz r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r11); \
150 stw r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r8); \
152 2: mfspr r8,SPRN_SPRG_RSCRATCH_##exc_level; \
153 stw r12,GPR12(r11); /* save various registers */\
155 stw r10,_LINK(r11); \
156 mfspr r12,SPRN_DEAR; /* save DEAR and ESR in the frame */\
157 stw r12,_DEAR(r11); /* since they may have had stuff */\
158 mfspr r9,SPRN_ESR; /* in them at the point where the */\
159 stw r9,_ESR(r11); /* exception was taken */\
160 mfspr r12,exc_level_srr0; \
162 mfspr r9,exc_level_srr1; \
165 rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
167 SAVE_4GPRS(3, r11); \
170 #define CRITICAL_EXCEPTION_PROLOG(intno) \
171 EXC_LEVEL_EXCEPTION_PROLOG(CRIT, intno, SPRN_CSRR0, SPRN_CSRR1)
172 #define DEBUG_EXCEPTION_PROLOG \
173 EXC_LEVEL_EXCEPTION_PROLOG(DBG, DEBUG, SPRN_DSRR0, SPRN_DSRR1)
174 #define MCHECK_EXCEPTION_PROLOG \
175 EXC_LEVEL_EXCEPTION_PROLOG(MC, MACHINE_CHECK, \
176 SPRN_MCSRR0, SPRN_MCSRR1)
179 * Guest Doorbell -- this is a bit odd in that uses GSRR0/1 despite
180 * being delivered to the host. This exception can only happen
181 * inside a KVM guest -- so we just handle up to the DO_KVM rather
182 * than try to fit this into one of the existing prolog macros.
184 #define GUEST_DOORBELL_EXCEPTION \
185 START_EXCEPTION(GuestDoorbell); \
186 mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
187 mfspr r10, SPRN_SPRG_THREAD; \
188 stw r11, THREAD_NORMSAVE(0)(r10); \
189 mfspr r11, SPRN_SRR1; \
190 stw r13, THREAD_NORMSAVE(2)(r10); \
191 mfcr r13; /* save CR in r13 for now */\
192 DO_KVM BOOKE_INTERRUPT_GUEST_DBELL SPRN_GSRR1; \
198 #define START_EXCEPTION(label) \
202 #define EXCEPTION(n, intno, label, hdlr, xfer) \
203 START_EXCEPTION(label); \
204 NORMAL_EXCEPTION_PROLOG(intno); \
205 addi r3,r1,STACK_FRAME_OVERHEAD; \
208 #define CRITICAL_EXCEPTION(n, intno, label, hdlr) \
209 START_EXCEPTION(label); \
210 CRITICAL_EXCEPTION_PROLOG(intno); \
211 addi r3,r1,STACK_FRAME_OVERHEAD; \
212 EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
213 NOCOPY, crit_transfer_to_handler, \
216 #define MCHECK_EXCEPTION(n, label, hdlr) \
217 START_EXCEPTION(label); \
218 MCHECK_EXCEPTION_PROLOG; \
221 addi r3,r1,STACK_FRAME_OVERHEAD; \
222 EXC_XFER_TEMPLATE(hdlr, n+4, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
223 NOCOPY, mcheck_transfer_to_handler, \
226 #define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret) \
228 stw r10,_TRAP(r11); \
236 #define COPY_EE(d, s) rlwimi d,s,0,16,16
239 #define EXC_XFER_STD(n, hdlr) \
240 EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full, \
241 ret_from_except_full)
243 #define EXC_XFER_LITE(n, hdlr) \
244 EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
247 #define EXC_XFER_EE(n, hdlr) \
248 EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
249 ret_from_except_full)
251 #define EXC_XFER_EE_LITE(n, hdlr) \
252 EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
255 /* Check for a single step debug exception while in an exception
256 * handler before state has been saved. This is to catch the case
257 * where an instruction that we are trying to single step causes
258 * an exception (eg ITLB/DTLB miss) and thus the first instruction of
259 * the exception handler generates a single step debug exception.
261 * If we get a debug trap on the first instruction of an exception handler,
262 * we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is
263 * a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR).
264 * The exception handler was handling a non-critical interrupt, so it will
265 * save (and later restore) the MSR via SPRN_CSRR1, which will still have
266 * the MSR_DE bit set.
268 #define DEBUG_DEBUG_EXCEPTION \
269 START_EXCEPTION(DebugDebug); \
270 DEBUG_EXCEPTION_PROLOG; \
273 * If there is a single step or branch-taken exception in an \
274 * exception entry sequence, it was probably meant to apply to \
275 * the code where the exception occurred (since exception entry \
276 * doesn't turn off DE automatically). We simulate the effect \
277 * of turning off DE on entry to an exception handler by turning \
278 * off DE in the DSRR1 value and clearing the debug status. \
280 mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
281 andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
284 lis r10,interrupt_base@h; /* check if exception in vectors */ \
285 ori r10,r10,interrupt_base@l; \
287 blt+ 2f; /* addr below exception vectors */ \
289 lis r10,interrupt_end@h; \
290 ori r10,r10,interrupt_end@l; \
292 bgt+ 2f; /* addr above exception vectors */ \
294 /* here it looks like we got an inappropriate debug exception. */ \
295 1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CDRR1 value */ \
296 lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
297 mtspr SPRN_DBSR,r10; \
298 /* restore state and get out */ \
303 mtspr SPRN_DSRR0,r12; \
304 mtspr SPRN_DSRR1,r9; \
306 lwz r12,GPR12(r11); \
307 mtspr SPRN_SPRG_WSCRATCH_DBG,r8; \
308 BOOKE_LOAD_EXC_LEVEL_STACK(DBG); /* r8 points to the debug stack */ \
311 mfspr r8,SPRN_SPRG_RSCRATCH_DBG; \
316 /* continue normal handling for a debug exception... */ \
317 2: mfspr r4,SPRN_DBSR; \
318 addi r3,r1,STACK_FRAME_OVERHEAD; \
319 EXC_XFER_TEMPLATE(DebugException, 0x2008, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, debug_transfer_to_handler, ret_from_debug_exc)
321 #define DEBUG_CRIT_EXCEPTION \
322 START_EXCEPTION(DebugCrit); \
323 CRITICAL_EXCEPTION_PROLOG(DEBUG); \
326 * If there is a single step or branch-taken exception in an \
327 * exception entry sequence, it was probably meant to apply to \
328 * the code where the exception occurred (since exception entry \
329 * doesn't turn off DE automatically). We simulate the effect \
330 * of turning off DE on entry to an exception handler by turning \
331 * off DE in the CSRR1 value and clearing the debug status. \
333 mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
334 andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
337 lis r10,interrupt_base@h; /* check if exception in vectors */ \
338 ori r10,r10,interrupt_base@l; \
340 blt+ 2f; /* addr below exception vectors */ \
342 lis r10,interrupt_end@h; \
343 ori r10,r10,interrupt_end@l; \
345 bgt+ 2f; /* addr above exception vectors */ \
347 /* here it looks like we got an inappropriate debug exception. */ \
348 1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CSRR1 value */ \
349 lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
350 mtspr SPRN_DBSR,r10; \
351 /* restore state and get out */ \
356 mtspr SPRN_CSRR0,r12; \
357 mtspr SPRN_CSRR1,r9; \
359 lwz r12,GPR12(r11); \
360 mtspr SPRN_SPRG_WSCRATCH_CRIT,r8; \
361 BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */ \
364 mfspr r8,SPRN_SPRG_RSCRATCH_CRIT; \
369 /* continue normal handling for a critical exception... */ \
370 2: mfspr r4,SPRN_DBSR; \
371 addi r3,r1,STACK_FRAME_OVERHEAD; \
372 EXC_XFER_TEMPLATE(DebugException, 0x2002, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, crit_transfer_to_handler, ret_from_crit_exc)
374 #define DATA_STORAGE_EXCEPTION \
375 START_EXCEPTION(DataStorage) \
376 NORMAL_EXCEPTION_PROLOG(DATA_STORAGE); \
377 mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
379 mfspr r4,SPRN_DEAR; /* Grab the DEAR */ \
380 EXC_XFER_LITE(0x0300, handle_page_fault)
382 #define INSTRUCTION_STORAGE_EXCEPTION \
383 START_EXCEPTION(InstructionStorage) \
384 NORMAL_EXCEPTION_PROLOG(INST_STORAGE); \
385 mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
387 mr r4,r12; /* Pass SRR0 as arg2 */ \
388 li r5,0; /* Pass zero as arg3 */ \
389 EXC_XFER_LITE(0x0400, handle_page_fault)
391 #define ALIGNMENT_EXCEPTION \
392 START_EXCEPTION(Alignment) \
393 NORMAL_EXCEPTION_PROLOG(ALIGNMENT); \
394 mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \
396 addi r3,r1,STACK_FRAME_OVERHEAD; \
397 EXC_XFER_EE(0x0600, alignment_exception)
399 #define PROGRAM_EXCEPTION \
400 START_EXCEPTION(Program) \
401 NORMAL_EXCEPTION_PROLOG(PROGRAM); \
402 mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \
404 addi r3,r1,STACK_FRAME_OVERHEAD; \
405 EXC_XFER_STD(0x0700, program_check_exception)
407 #define DECREMENTER_EXCEPTION \
408 START_EXCEPTION(Decrementer) \
409 NORMAL_EXCEPTION_PROLOG(DECREMENTER); \
410 lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \
411 mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \
412 addi r3,r1,STACK_FRAME_OVERHEAD; \
413 EXC_XFER_LITE(0x0900, timer_interrupt)
415 #define FP_UNAVAILABLE_EXCEPTION \
416 START_EXCEPTION(FloatingPointUnavailable) \
417 NORMAL_EXCEPTION_PROLOG(FP_UNAVAIL); \
419 bl load_up_fpu; /* if from user, just load it up */ \
420 b fast_exception_return; \
421 1: addi r3,r1,STACK_FRAME_OVERHEAD; \
422 EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
425 struct exception_regs
{
438 unsigned long saved_ksp_limit
;
441 /* ensure this structure is always sized to a multiple of the stack alignment */
442 #define STACK_EXC_LVL_FRAME_SIZE _ALIGN_UP(sizeof (struct exception_regs), 16)
444 #endif /* __ASSEMBLY__ */
445 #endif /* __HEAD_BOOKE_H__ */