entry.S 32 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4
/*
 *  arch/s390/kernel/entry.S
 *    S390 low-level entry points.
 *
5
 *    Copyright (C) IBM Corp. 1999,2006
Linus Torvalds's avatar
Linus Torvalds committed
6
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
Heiko Carstens's avatar
Heiko Carstens committed
7 8
 *		 Hartmut Penner (hp@de.ibm.com),
 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
9
 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
Linus Torvalds's avatar
Linus Torvalds committed
10 11 12 13
 */

#include <linux/sys.h>
#include <linux/linkage.h>
14
#include <linux/init.h>
Linus Torvalds's avatar
Linus Torvalds committed
15 16 17 18
#include <asm/cache.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
19
#include <asm/asm-offsets.h>
Linus Torvalds's avatar
Linus Torvalds committed
20 21 22 23 24 25 26
#include <asm/unistd.h>
#include <asm/page.h>

/*
 * Stack layout for the system_call stack entry.
 * The first few entries are identical to the user_regs_struct.
 */
Heiko Carstens's avatar
Heiko Carstens committed
27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
SP_PTREGS    =	STACK_FRAME_OVERHEAD
SP_ARGS      =	STACK_FRAME_OVERHEAD + __PT_ARGS
SP_PSW	     =	STACK_FRAME_OVERHEAD + __PT_PSW
SP_R0	     =	STACK_FRAME_OVERHEAD + __PT_GPRS
SP_R1	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 4
SP_R2	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 8
SP_R3	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 12
SP_R4	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 16
SP_R5	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 20
SP_R6	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 24
SP_R7	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 28
SP_R8	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 32
SP_R9	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 36
SP_R10	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 40
SP_R11	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 44
SP_R12	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 48
SP_R13	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 52
SP_R14	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 56
SP_R15	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 60
SP_ORIG_R2   =	STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
SP_ILC	     =	STACK_FRAME_OVERHEAD + __PT_ILC
48
SP_SVCNR     =	STACK_FRAME_OVERHEAD + __PT_SVCNR
Heiko Carstens's avatar
Heiko Carstens committed
49
SP_SIZE      =	STACK_FRAME_OVERHEAD + __PT_SIZE
Linus Torvalds's avatar
Linus Torvalds committed
50

Martin Schwidefsky's avatar
Martin Schwidefsky committed
51
_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
52
		 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
Martin Schwidefsky's avatar
Martin Schwidefsky committed
53
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
54
		 _TIF_MCCK_PENDING)
55
_TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
56
		_TIF_SECCOMP>>8 | _TIF_SYSCALL_TRACEPOINT>>8)
Linus Torvalds's avatar
Linus Torvalds committed
57 58 59 60 61 62

STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE  = 1 << STACK_SHIFT

#define BASED(name) name-system_call(%r13)

63 64
#ifdef CONFIG_TRACE_IRQFLAGS
	.macro	TRACE_IRQS_ON
65 66
	basr	%r2,%r0
	l	%r1,BASED(.Ltrace_irq_on_caller)
67 68 69 70
	basr	%r14,%r1
	.endm

	.macro	TRACE_IRQS_OFF
71 72
	basr	%r2,%r0
	l	%r1,BASED(.Ltrace_irq_off_caller)
73 74
	basr	%r14,%r1
	.endm
75

76
	.macro	TRACE_IRQS_CHECK_ON
77
	tm	SP_PSW(%r15),0x03	# irqs enabled?
78 79 80 81 82 83 84 85 86 87
	bz	BASED(0f)
	TRACE_IRQS_ON
0:
	.endm

	.macro	TRACE_IRQS_CHECK_OFF
	tm	SP_PSW(%r15),0x03	# irqs enabled?
	bz	BASED(0f)
	TRACE_IRQS_OFF
0:
88
	.endm
89 90 91
#else
#define TRACE_IRQS_ON
#define TRACE_IRQS_OFF
92 93
#define TRACE_IRQS_CHECK_ON
#define TRACE_IRQS_CHECK_OFF
94 95 96 97 98 99 100 101 102 103 104
#endif

#ifdef CONFIG_LOCKDEP
	.macro	LOCKDEP_SYS_EXIT
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
	jz	0f
	l	%r1,BASED(.Llockdep_sys_exit)
	basr	%r14,%r1
0:
	.endm
#else
105
#define LOCKDEP_SYS_EXIT
106 107
#endif

Linus Torvalds's avatar
Linus Torvalds committed
108 109 110 111 112 113 114 115
/*
 * Register usage in interrupt handlers:
 *    R9  - pointer to current task structure
 *    R13 - pointer to literal pool
 *    R14 - return register for function calls
 *    R15 - kernel stack pointer
 */

Heiko Carstens's avatar
Heiko Carstens committed
116
	.macro	UPDATE_VTIME lc_from,lc_to,lc_sum
Linus Torvalds's avatar
Linus Torvalds committed
117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133
	lm	%r10,%r11,\lc_from
	sl	%r10,\lc_to
	sl	%r11,\lc_to+4
	bc	3,BASED(0f)
	sl	%r10,BASED(.Lc_1)
0:	al	%r10,\lc_sum
	al	%r11,\lc_sum+4
	bc	12,BASED(1f)
	al	%r10,BASED(.Lc_1)
1:	stm	%r10,%r11,\lc_sum
	.endm

	.macro	SAVE_ALL_BASE savearea
	stm	%r12,%r15,\savearea
	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
	.endm

134 135 136 137 138
	.macro	SAVE_ALL_SVC psworg,savearea
	la	%r12,\psworg
	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
	.endm

139
	.macro	SAVE_ALL_SYNC psworg,savearea
Linus Torvalds's avatar
Linus Torvalds committed
140 141 142 143
	la	%r12,\psworg
	tm	\psworg+1,0x01		# test problem state bit
	bz	BASED(2f)		# skip stack setup save
	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
144 145 146 147 148 149 150 151 152 153 154
#ifdef CONFIG_CHECK_STACK
	b	BASED(3f)
2:	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
	bz	BASED(stack_overflow)
3:
#endif
2:
	.endm

	.macro	SAVE_ALL_ASYNC psworg,savearea
	la	%r12,\psworg
Linus Torvalds's avatar
Linus Torvalds committed
155 156 157 158 159 160 161 162
	tm	\psworg+1,0x01		# test problem state bit
	bnz	BASED(1f)		# from user -> load async stack
	clc	\psworg+4(4),BASED(.Lcritical_end)
	bhe	BASED(0f)
	clc	\psworg+4(4),BASED(.Lcritical_start)
	bl	BASED(0f)
	l	%r14,BASED(.Lcleanup_critical)
	basr	%r14,%r14
163
	tm	1(%r12),0x01		# retest problem state after cleanup
Linus Torvalds's avatar
Linus Torvalds committed
164 165 166 167 168 169 170 171 172 173 174 175
	bnz	BASED(1f)
0:	l	%r14,__LC_ASYNC_STACK	# are we already on the async stack ?
	slr	%r14,%r15
	sra	%r14,STACK_SHIFT
	be	BASED(2f)
1:	l	%r15,__LC_ASYNC_STACK
#ifdef CONFIG_CHECK_STACK
	b	BASED(3f)
2:	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
	bz	BASED(stack_overflow)
3:
#endif
176 177 178
2:
	.endm

Heiko Carstens's avatar
Heiko Carstens committed
179
	.macro	CREATE_STACK_FRAME psworg,savearea
180
	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
Linus Torvalds's avatar
Linus Torvalds committed
181 182
	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
	st	%r2,SP_ORIG_R2(%r15)	# store original content of gpr 2
183
	icm	%r12,12,__LC_SVC_ILC
Linus Torvalds's avatar
Linus Torvalds committed
184
	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
185
	st	%r12,SP_ILC(%r15)
Linus Torvalds's avatar
Linus Torvalds committed
186 187 188 189 190
	mvc	SP_R12(16,%r15),\savearea # move %r12-%r15 to stack
	la	%r12,0
	st	%r12,__SF_BACKCHAIN(%r15)	# clear back chain
	.endm

Heiko Carstens's avatar
Heiko Carstens committed
191
	.macro	RESTORE_ALL psworg,sync
192
	mvc	\psworg(8),SP_PSW(%r15) # move user PSW to lowcore
Linus Torvalds's avatar
Linus Torvalds committed
193
	.if !\sync
194
	ni	\psworg+1,0xfd		# clear wait state bit
Linus Torvalds's avatar
Linus Torvalds committed
195 196
	.endif
	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15 of user
197
	stpt	__LC_EXIT_TIMER
198
	lpsw	\psworg			# back to caller
Linus Torvalds's avatar
Linus Torvalds committed
199 200 201 202 203 204 205 206 207
	.endm

/*
 * Scheduler resume function, called by switch_to
 *  gpr2 = (task_struct *) prev
 *  gpr3 = (task_struct *) next
 * Returns:
 *  gpr2 = prev
 */
Heiko Carstens's avatar
Heiko Carstens committed
208
	.globl	__switch_to
Linus Torvalds's avatar
Linus Torvalds committed
209
__switch_to:
Heiko Carstens's avatar
Heiko Carstens committed
210
	basr	%r1,0
Linus Torvalds's avatar
Linus Torvalds committed
211 212 213
__switch_to_base:
	tm	__THREAD_per(%r3),0xe8		# new process is using per ?
	bz	__switch_to_noper-__switch_to_base(%r1)	# if not we're fine
Heiko Carstens's avatar
Heiko Carstens committed
214 215 216 217
	stctl	%c9,%c11,__SF_EMPTY(%r15)	# We are using per stuff
	clc	__THREAD_per(12,%r3),__SF_EMPTY(%r15)
	be	__switch_to_noper-__switch_to_base(%r1)	# we got away w/o bashing TLB's
	lctl	%c9,%c11,__THREAD_per(%r3)	# Nope we didn't
Linus Torvalds's avatar
Linus Torvalds committed
218
__switch_to_noper:
219 220 221 222 223 224 225
	l	%r4,__THREAD_info(%r2)		# get thread_info of prev
	tm	__TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
	bz	__switch_to_no_mcck-__switch_to_base(%r1)
	ni	__TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
	l	%r4,__THREAD_info(%r3)		# get thread_info of next
	oi	__TI_flags+3(%r4),_TIF_MCCK_PENDING # set it in next
__switch_to_no_mcck:
Heiko Carstens's avatar
Heiko Carstens committed
226
	stm	%r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
Linus Torvalds's avatar
Linus Torvalds committed
227 228 229 230 231
	st	%r15,__THREAD_ksp(%r2)	# store kernel stack to prev->tss.ksp
	l	%r15,__THREAD_ksp(%r3)	# load kernel stack from next->tss.ksp
	lm	%r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
	st	%r3,__LC_CURRENT	# __LC_CURRENT = current task struct
	lctl	%c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
Heiko Carstens's avatar
Heiko Carstens committed
232
	l	%r3,__THREAD_info(%r3)	# load thread_info from task struct
Linus Torvalds's avatar
Linus Torvalds committed
233 234 235 236 237 238 239 240 241 242 243
	st	%r3,__LC_THREAD_INFO
	ahi	%r3,STACK_SIZE
	st	%r3,__LC_KERNEL_STACK	# __LC_KERNEL_STACK = new kernel stack
	br	%r14

__critical_start:
/*
 * SVC interrupt handler routine. System calls are synchronous events and
 * are executed with interrupts enabled.
 */

Heiko Carstens's avatar
Heiko Carstens committed
244
	.globl	system_call
Linus Torvalds's avatar
Linus Torvalds committed
245
system_call:
246
	stpt	__LC_SYNC_ENTER_TIMER
Linus Torvalds's avatar
Linus Torvalds committed
247 248
sysc_saveall:
	SAVE_ALL_BASE __LC_SAVE_AREA
249
	SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
250
	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
Linus Torvalds's avatar
Linus Torvalds committed
251 252 253 254 255 256 257 258 259
	lh	%r7,0x8a	  # get svc number from lowcore
sysc_vtime:
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
sysc_stime:
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
sysc_update:
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
sysc_do_svc:
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
260
	ltr	%r7,%r7			# test for svc 0
Heiko Carstens's avatar
Heiko Carstens committed
261
	bnz	BASED(sysc_nr_ok)	# svc number > 0
Linus Torvalds's avatar
Linus Torvalds committed
262 263 264
	# svc 0: system call number in %r1
	cl	%r1,BASED(.Lnr_syscalls)
	bnl	BASED(sysc_nr_ok)
Heiko Carstens's avatar
Heiko Carstens committed
265
	lr	%r7,%r1 	  # copy svc number to %r7
Linus Torvalds's avatar
Linus Torvalds committed
266 267 268
sysc_nr_ok:
	mvc	SP_ARGS(4,%r15),SP_R7(%r15)
sysc_do_restart:
269 270
	sth	%r7,SP_SVCNR(%r15)
	sll	%r7,2		  # svc number *4
271
	l	%r8,BASED(.Lsysc_table)
272
	tm	__TI_flags+2(%r9),_TIF_SYSCALL
273
	l	%r8,0(%r7,%r8)	  # get system call addr.
Heiko Carstens's avatar
Heiko Carstens committed
274 275 276
	bnz	BASED(sysc_tracesys)
	basr	%r14,%r8	  # call sys_xxxx
	st	%r2,SP_R2(%r15)   # store return value (change R2 on stack)
Linus Torvalds's avatar
Linus Torvalds committed
277 278

sysc_return:
279 280
	LOCKDEP_SYS_EXIT
sysc_tif:
Linus Torvalds's avatar
Linus Torvalds committed
281 282
	tm	__TI_flags+3(%r9),_TIF_WORK_SVC
	bnz	BASED(sysc_work)  # there is work to do (signals etc.)
283
sysc_restore:
Heiko Carstens's avatar
Heiko Carstens committed
284
	RESTORE_ALL __LC_RETURN_PSW,1
285 286
sysc_done:

Linus Torvalds's avatar
Linus Torvalds committed
287
#
288
# There is work to do, but first we need to check if we return to userspace.
Linus Torvalds's avatar
Linus Torvalds committed
289 290
#
sysc_work:
291 292
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
	bno	BASED(sysc_restore)
293 294 295 296

#
# One of the work bits is on. Find out which one.
#
297
sysc_work_tif:
298 299
	tm	__TI_flags+3(%r9),_TIF_MCCK_PENDING
	bo	BASED(sysc_mcck_pending)
Linus Torvalds's avatar
Linus Torvalds committed
300 301
	tm	__TI_flags+3(%r9),_TIF_NEED_RESCHED
	bo	BASED(sysc_reschedule)
302
	tm	__TI_flags+3(%r9),_TIF_SIGPENDING
303
	bo	BASED(sysc_sigpending)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
304
	tm	__TI_flags+3(%r9),_TIF_NOTIFY_RESUME
305
	bo	BASED(sysc_notify_resume)
Linus Torvalds's avatar
Linus Torvalds committed
306 307 308 309
	tm	__TI_flags+3(%r9),_TIF_RESTART_SVC
	bo	BASED(sysc_restart)
	tm	__TI_flags+3(%r9),_TIF_SINGLE_STEP
	bo	BASED(sysc_singlestep)
310
	b	BASED(sysc_return)	# beware of critical section cleanup
Linus Torvalds's avatar
Linus Torvalds committed
311 312 313

#
# _TIF_NEED_RESCHED is set, call schedule
Heiko Carstens's avatar
Heiko Carstens committed
314 315 316
#
sysc_reschedule:
	l	%r1,BASED(.Lschedule)
317
	la	%r14,BASED(sysc_return)
Heiko Carstens's avatar
Heiko Carstens committed
318
	br	%r1			# call scheduler
Linus Torvalds's avatar
Linus Torvalds committed
319

320 321 322 323 324
#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
	l	%r1,BASED(.Ls390_handle_mcck)
325
	la	%r14,BASED(sysc_return)
326 327
	br	%r1			# TIF bit will be cleared by handler

Linus Torvalds's avatar
Linus Torvalds committed
328
#
329
# _TIF_SIGPENDING is set, call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
330
#
Heiko Carstens's avatar
Heiko Carstens committed
331
sysc_sigpending:
Linus Torvalds's avatar
Linus Torvalds committed
332
	ni	__TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
Heiko Carstens's avatar
Heiko Carstens committed
333 334 335
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_signal)
	basr	%r14,%r1		# call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
336 337 338 339
	tm	__TI_flags+3(%r9),_TIF_RESTART_SVC
	bo	BASED(sysc_restart)
	tm	__TI_flags+3(%r9),_TIF_SINGLE_STEP
	bo	BASED(sysc_singlestep)
340
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
341

Martin Schwidefsky's avatar
Martin Schwidefsky committed
342 343 344 345 346 347
#
# _TIF_NOTIFY_RESUME is set, call do_notify_resume
#
sysc_notify_resume:
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_notify_resume)
348
	la	%r14,BASED(sysc_return)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
349 350 351
	br	%r1			# call do_notify_resume


Linus Torvalds's avatar
Linus Torvalds committed
352 353 354 355 356
#
# _TIF_RESTART_SVC is set, set up registers and restart svc
#
sysc_restart:
	ni	__TI_flags+3(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
Heiko Carstens's avatar
Heiko Carstens committed
357
	l	%r7,SP_R2(%r15) 	# load new svc number
Linus Torvalds's avatar
Linus Torvalds committed
358
	mvc	SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
Heiko Carstens's avatar
Heiko Carstens committed
359 360
	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
	b	BASED(sysc_do_restart)	# restart svc
Linus Torvalds's avatar
Linus Torvalds committed
361 362 363 364 365 366

#
# _TIF_SINGLE_STEP is set, call do_single_step
#
sysc_singlestep:
	ni	__TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
367 368
	mvi	SP_SVCNR(%r15),0xff	# set trap indication to pgm check
	mvi	SP_SVCNR+1(%r15),0xff
Linus Torvalds's avatar
Linus Torvalds committed
369 370
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
371
	la	%r14,BASED(sysc_return)	# load adr. of system return
Linus Torvalds's avatar
Linus Torvalds committed
372 373 374
	br	%r1			# branch to do_single_step

#
Martin Schwidefsky's avatar
Martin Schwidefsky committed
375 376
# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
# and after the system call
Linus Torvalds's avatar
Linus Torvalds committed
377 378
#
sysc_tracesys:
Martin Schwidefsky's avatar
Martin Schwidefsky committed
379
	l	%r1,BASED(.Ltrace_entry)
Heiko Carstens's avatar
Heiko Carstens committed
380
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
381 382 383 384
	la	%r3,0
	srl	%r7,2
	st	%r7,SP_R2(%r15)
	basr	%r14,%r1
Martin Schwidefsky's avatar
Martin Schwidefsky committed
385
	cl	%r2,BASED(.Lnr_syscalls)
Linus Torvalds's avatar
Linus Torvalds committed
386
	bnl	BASED(sysc_tracenogo)
387
	l	%r8,BASED(.Lsysc_table)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
388
	lr	%r7,%r2
389
	sll	%r7,2			# svc number *4
390
	l	%r8,0(%r7,%r8)
Linus Torvalds's avatar
Linus Torvalds committed
391 392 393
sysc_tracego:
	lm	%r3,%r6,SP_R3(%r15)
	l	%r2,SP_ORIG_R2(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
394 395
	basr	%r14,%r8		# call sys_xxx
	st	%r2,SP_R2(%r15)		# store return value
Linus Torvalds's avatar
Linus Torvalds committed
396
sysc_tracenogo:
397
	tm	__TI_flags+2(%r9),_TIF_SYSCALL
Heiko Carstens's avatar
Heiko Carstens committed
398
	bz	BASED(sysc_return)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
399
	l	%r1,BASED(.Ltrace_exit)
Heiko Carstens's avatar
Heiko Carstens committed
400
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
401 402 403 404 405 406
	la	%r14,BASED(sysc_return)
	br	%r1

#
# a new process exits the kernel with ret_from_fork
#
Heiko Carstens's avatar
Heiko Carstens committed
407
	.globl	ret_from_fork
Linus Torvalds's avatar
Linus Torvalds committed
408 409 410 411 412 413
ret_from_fork:
	l	%r13,__LC_SVC_NEW_PSW+4
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
	tm	SP_PSW+1(%r15),0x01	# forking a kernel thread ?
	bo	BASED(0f)
	st	%r15,SP_R15(%r15)	# store stack pointer for new kthread
Heiko Carstens's avatar
Heiko Carstens committed
414 415
0:	l	%r1,BASED(.Lschedtail)
	basr	%r14,%r1
416
	TRACE_IRQS_ON
Heiko Carstens's avatar
Heiko Carstens committed
417
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
418
	b	BASED(sysc_tracenogo)
Linus Torvalds's avatar
Linus Torvalds committed
419 420

#
421 422
# kernel_execve function needs to deal with pt_regs that is not
# at the usual place
Linus Torvalds's avatar
Linus Torvalds committed
423
#
424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442
	.globl	kernel_execve
kernel_execve:
	stm	%r12,%r15,48(%r15)
	lr	%r14,%r15
	l	%r13,__LC_SVC_NEW_PSW+4
	s	%r15,BASED(.Lc_spsize)
	st	%r14,__SF_BACKCHAIN(%r15)
	la	%r12,SP_PTREGS(%r15)
	xc	0(__PT_SIZE,%r12),0(%r12)
	l	%r1,BASED(.Ldo_execve)
	lr	%r5,%r12
	basr	%r14,%r1
	ltr	%r2,%r2
	be	BASED(0f)
	a	%r15,BASED(.Lc_spsize)
	lm	%r12,%r15,48(%r15)
	br	%r14
	# execve succeeded.
0:	stnsm	__SF_EMPTY(%r15),0xfc	# disable interrupts
443
	TRACE_IRQS_OFF
444 445 446 447 448
	l	%r15,__LC_KERNEL_STACK	# load ksp
	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
	l	%r9,__LC_THREAD_INFO
	mvc	SP_PTREGS(__PT_SIZE,%r15),0(%r12)	# copy pt_regs
	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
449
	TRACE_IRQS_ON
450 451 452 453
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	l	%r1,BASED(.Lexecve_tail)
	basr	%r14,%r1
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
454 455 456 457 458

/*
 * Program check handler routine
 */

Heiko Carstens's avatar
Heiko Carstens committed
459
	.globl	pgm_check_handler
Linus Torvalds's avatar
Linus Torvalds committed
460 461 462 463 464 465 466 467 468 469 470 471 472 473
pgm_check_handler:
/*
 * First we need to check for a special case:
 * Single stepping an instruction that disables the PER event mask will
 * cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
 * For a single stepped SVC the program check handler gets control after
 * the SVC new PSW has been loaded. But we want to execute the SVC first and
 * then handle the PER event. Therefore we update the SVC old PSW to point
 * to the pgm_check_handler and branch to the SVC handler after we checked
 * if we have to load the kernel stack register.
 * For every other possible cause for PER event without the PER mask set
 * we just ignore the PER event (FIXME: is there anything we have to do
 * for LPSW?).
 */
474
	stpt	__LC_SYNC_ENTER_TIMER
Linus Torvalds's avatar
Linus Torvalds committed
475
	SAVE_ALL_BASE __LC_SAVE_AREA
Heiko Carstens's avatar
Heiko Carstens committed
476 477
	tm	__LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
	bnz	BASED(pgm_per)		# got per exception -> special case
478
	SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
479
	CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
Linus Torvalds's avatar
Linus Torvalds committed
480 481 482 483 484 485
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(pgm_no_vtime)
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime:
486
	TRACE_IRQS_CHECK_OFF
Linus Torvalds's avatar
Linus Torvalds committed
487
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
Heiko Carstens's avatar
Heiko Carstens committed
488
	l	%r3,__LC_PGM_ILC	# load program interruption code
Linus Torvalds's avatar
Linus Torvalds committed
489 490 491
	la	%r8,0x7f
	nr	%r8,%r3
pgm_do_call:
Heiko Carstens's avatar
Heiko Carstens committed
492 493 494 495
	l	%r7,BASED(.Ljump_table)
	sll	%r8,2
	l	%r7,0(%r8,%r7)		# load address of handler routine
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
496 497 498 499
	basr	%r14,%r7		# branch to interrupt-handler
pgm_exit:
	TRACE_IRQS_CHECK_ON
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
500 501 502 503 504

#
# handle per exception
#
pgm_per:
Heiko Carstens's avatar
Heiko Carstens committed
505 506
	tm	__LC_PGM_OLD_PSW,0x40	# test if per event recording is on
	bnz	BASED(pgm_per_std)	# ok, normal per event from user space
Linus Torvalds's avatar
Linus Torvalds committed
507
# ok its one of the special cases, now we need to find out which one
Heiko Carstens's avatar
Heiko Carstens committed
508 509
	clc	__LC_PGM_OLD_PSW(8),__LC_SVC_NEW_PSW
	be	BASED(pgm_svcper)
Linus Torvalds's avatar
Linus Torvalds committed
510
# no interesting special case, ignore PER event
Heiko Carstens's avatar
Heiko Carstens committed
511 512
	lm	%r12,%r15,__LC_SAVE_AREA
	lpsw	0x28
Linus Torvalds's avatar
Linus Torvalds committed
513 514 515 516 517

#
# Normal per exception
#
pgm_per_std:
518
	SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
519
	CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
Linus Torvalds's avatar
Linus Torvalds committed
520 521 522 523 524 525
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(pgm_no_vtime2)
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime2:
526
	TRACE_IRQS_CHECK_OFF
Linus Torvalds's avatar
Linus Torvalds committed
527 528
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
	l	%r1,__TI_task(%r9)
529 530
	tm	SP_PSW+1(%r15),0x01	# kernel per event ?
	bz	BASED(kernel_per)
Linus Torvalds's avatar
Linus Torvalds committed
531 532 533 534
	mvc	__THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
	mvc	__THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS
	mvc	__THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
	oi	__TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
Heiko Carstens's avatar
Heiko Carstens committed
535
	l	%r3,__LC_PGM_ILC	# load program interruption code
Linus Torvalds's avatar
Linus Torvalds committed
536
	la	%r8,0x7f
Heiko Carstens's avatar
Heiko Carstens committed
537
	nr	%r8,%r3 		# clear per-event-bit and ilc
538 539 540 541 542 543 544 545 546 547
	be	BASED(pgm_exit2)	# only per or per+check ?
	l	%r7,BASED(.Ljump_table)
	sll	%r8,2
	l	%r7,0(%r8,%r7)		# load address of handler routine
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	basr	%r14,%r7		# branch to interrupt-handler
pgm_exit2:
	TRACE_IRQS_ON
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
548 549 550 551 552

#
# it was a single stepped SVC that is causing all the trouble
#
pgm_svcper:
553
	SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
554
	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
Linus Torvalds's avatar
Linus Torvalds committed
555 556 557 558 559
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
	lh	%r7,0x8a		# get svc number from lowcore
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
560
	TRACE_IRQS_OFF
561 562 563 564
	l	%r8,__TI_task(%r9)
	mvc	__THREAD_per+__PER_atmid(2,%r8),__LC_PER_ATMID
	mvc	__THREAD_per+__PER_address(4,%r8),__LC_PER_ADDRESS
	mvc	__THREAD_per+__PER_access_id(1,%r8),__LC_PER_ACCESS_ID
Linus Torvalds's avatar
Linus Torvalds committed
565
	oi	__TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
566
	TRACE_IRQS_ON
Linus Torvalds's avatar
Linus Torvalds committed
567
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
568
	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
Linus Torvalds's avatar
Linus Torvalds committed
569 570
	b	BASED(sysc_do_svc)

Michael Grundy's avatar
Michael Grundy committed
571 572 573 574
#
# per was called from kernel, must be kprobes
#
kernel_per:
575 576
	mvi	SP_SVCNR(%r15),0xff	# set trap indication to pgm check
	mvi	SP_SVCNR+1(%r15),0xff
Michael Grundy's avatar
Michael Grundy committed
577 578
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
579 580
	basr	%r14,%r1		# branch to do_single_step
	b	BASED(pgm_exit)
Michael Grundy's avatar
Michael Grundy committed
581

Linus Torvalds's avatar
Linus Torvalds committed
582 583 584 585
/*
 * IO interrupt handler routine
 */

Heiko Carstens's avatar
Heiko Carstens committed
586
	.globl io_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
587 588
io_int_handler:
	stck	__LC_INT_CLOCK
589
	stpt	__LC_ASYNC_ENTER_TIMER
Linus Torvalds's avatar
Linus Torvalds committed
590
	SAVE_ALL_BASE __LC_SAVE_AREA+16
591
	SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
592
	CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
Linus Torvalds's avatar
Linus Torvalds committed
593 594 595 596 597 598
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(io_no_vtime)
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
io_no_vtime:
599
	TRACE_IRQS_OFF
600
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
Heiko Carstens's avatar
Heiko Carstens committed
601 602 603
	l	%r1,BASED(.Ldo_IRQ)	# load address of do_IRQ
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	basr	%r14,%r1		# branch to standard irq handler
Linus Torvalds's avatar
Linus Torvalds committed
604
io_return:
605 606 607
	LOCKDEP_SYS_EXIT
	TRACE_IRQS_ON
io_tif:
Linus Torvalds's avatar
Linus Torvalds committed
608
	tm	__TI_flags+3(%r9),_TIF_WORK_INT
Heiko Carstens's avatar
Heiko Carstens committed
609
	bnz	BASED(io_work)		# there is work to do (signals etc.)
610
io_restore:
Heiko Carstens's avatar
Heiko Carstens committed
611
	RESTORE_ALL __LC_RETURN_PSW,0
612
io_done:
Linus Torvalds's avatar
Linus Torvalds committed
613

614
#
615 616 617 618 619
# There is work todo, find out in which context we have been interrupted:
# 1) if we return to user space we can do all _TIF_WORK_INT work
# 2) if we return to kernel code and preemptive scheduling is enabled check
#    the preemption counter and if it is zero call preempt_schedule_irq
# Before any work can be done, a switch to the kernel stack is required.
620 621 622
#
io_work:
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
623 624
	bo	BASED(io_work_user)	# yes -> do resched & signal
#ifdef CONFIG_PREEMPT
625
	# check for preemptive scheduling
Linus Torvalds's avatar
Linus Torvalds committed
626
	icm	%r0,15,__TI_precount(%r9)
627
	bnz	BASED(io_restore)	# preemption disabled
628 629
	tm	__TI_flags+3(%r9),_TIF_NEED_RESCHED
	bno	BASED(io_restore)
630
	# switch to kernel stack
Linus Torvalds's avatar
Linus Torvalds committed
631 632 633
	l	%r1,SP_R15(%r15)
	s	%r1,BASED(.Lc_spsize)
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
634
	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
635
	lr	%r15,%r1
636 637 638
	# TRACE_IRQS_ON already done at io_return, call
	# TRACE_IRQS_OFF to keep things symmetrical
	TRACE_IRQS_OFF
Heiko Carstens's avatar
Heiko Carstens committed
639
	l	%r1,BASED(.Lpreempt_schedule_irq)
640 641 642
	basr	%r14,%r1		# call preempt_schedule_irq
	b	BASED(io_return)
#else
643
	b	BASED(io_restore)
644
#endif
Linus Torvalds's avatar
Linus Torvalds committed
645

646 647 648
#
# Need to do work before returning to userspace, switch to kernel stack
#
649
io_work_user:
Linus Torvalds's avatar
Linus Torvalds committed
650 651 652
	l	%r1,__LC_KERNEL_STACK
	s	%r1,BASED(.Lc_spsize)
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
653
	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
654
	lr	%r15,%r1
655

Linus Torvalds's avatar
Linus Torvalds committed
656 657
#
# One of the work bits is on. Find out which one.
658
# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
Heiko Carstens's avatar
Heiko Carstens committed
659
#		and _TIF_MCCK_PENDING
Linus Torvalds's avatar
Linus Torvalds committed
660
#
661
io_work_tif:
662
	tm	__TI_flags+3(%r9),_TIF_MCCK_PENDING
Heiko Carstens's avatar
Heiko Carstens committed
663
	bo	BASED(io_mcck_pending)
Linus Torvalds's avatar
Linus Torvalds committed
664 665
	tm	__TI_flags+3(%r9),_TIF_NEED_RESCHED
	bo	BASED(io_reschedule)
666
	tm	__TI_flags+3(%r9),_TIF_SIGPENDING
667
	bo	BASED(io_sigpending)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
668
	tm	__TI_flags+3(%r9),_TIF_NOTIFY_RESUME
669 670
	bo	BASED(io_notify_resume)
	b	BASED(io_return)	# beware of critical section cleanup
Linus Torvalds's avatar
Linus Torvalds committed
671

672 673 674 675
#
# _TIF_MCCK_PENDING is set, call handler
#
io_mcck_pending:
676
	# TRACE_IRQS_ON already done at io_return
677
	l	%r1,BASED(.Ls390_handle_mcck)
Heiko Carstens's avatar
Heiko Carstens committed
678
	basr	%r14,%r1		# TIF bit will be cleared by handler
679 680
	TRACE_IRQS_OFF
	b	BASED(io_return)
681

Linus Torvalds's avatar
Linus Torvalds committed
682 683
#
# _TIF_NEED_RESCHED is set, call schedule
Heiko Carstens's avatar
Heiko Carstens committed
684 685
#
io_reschedule:
686
	# TRACE_IRQS_ON already done at io_return
Heiko Carstens's avatar
Heiko Carstens committed
687 688 689 690
	l	%r1,BASED(.Lschedule)
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	basr	%r14,%r1		# call scheduler
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
691
	TRACE_IRQS_OFF
692
	b	BASED(io_return)
Linus Torvalds's avatar
Linus Torvalds committed
693 694

#
695
# _TIF_SIGPENDING is set, call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
696
#
Heiko Carstens's avatar
Heiko Carstens committed
697
io_sigpending:
698
	# TRACE_IRQS_ON already done at io_return
Heiko Carstens's avatar
Heiko Carstens committed
699 700 701 702 703
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_signal)
	basr	%r14,%r1		# call do_signal
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
704
	TRACE_IRQS_OFF
705
	b	BASED(io_return)
Linus Torvalds's avatar
Linus Torvalds committed
706

Martin Schwidefsky's avatar
Martin Schwidefsky committed
707 708 709 710
#
# _TIF_SIGPENDING is set, call do_signal
#
io_notify_resume:
711
	# TRACE_IRQS_ON already done at io_return
Martin Schwidefsky's avatar
Martin Schwidefsky committed
712 713 714 715 716 717
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_notify_resume)
	basr	%r14,%r1		# call do_signal
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
	TRACE_IRQS_OFF
718
	b	BASED(io_return)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
719

Linus Torvalds's avatar
Linus Torvalds committed
720 721 722 723
/*
 * External interrupt handler routine
 */

Heiko Carstens's avatar
Heiko Carstens committed
724
	.globl	ext_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
725 726
ext_int_handler:
	stck	__LC_INT_CLOCK
727
	stpt	__LC_ASYNC_ENTER_TIMER
Linus Torvalds's avatar
Linus Torvalds committed
728
	SAVE_ALL_BASE __LC_SAVE_AREA+16
729
	SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
730
	CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
Linus Torvalds's avatar
Linus Torvalds committed
731 732 733 734 735 736 737
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(ext_no_vtime)
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
ext_no_vtime:
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
738
	TRACE_IRQS_OFF
Heiko Carstens's avatar
Heiko Carstens committed
739 740
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	lh	%r3,__LC_EXT_INT_CODE	# get interruption code
Linus Torvalds's avatar
Linus Torvalds committed
741 742 743 744
	l	%r1,BASED(.Ldo_extint)
	basr	%r14,%r1
	b	BASED(io_return)

745 746
__critical_end:

Linus Torvalds's avatar
Linus Torvalds committed
747 748 749 750
/*
 * Machine check handler routines
 */

Heiko Carstens's avatar
Heiko Carstens committed
751
	.globl mcck_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
752
mcck_int_handler:
753
	stck	__LC_MCCK_CLOCK
754 755
	spt	__LC_CPU_TIMER_SAVE_AREA	# revalidate cpu timer
	lm	%r0,%r15,__LC_GPREGS_SAVE_AREA	# revalidate gprs
Linus Torvalds's avatar
Linus Torvalds committed
756
	SAVE_ALL_BASE __LC_SAVE_AREA+32
757
	la	%r12,__LC_MCK_OLD_PSW
Heiko Carstens's avatar
Heiko Carstens committed
758
	tm	__LC_MCCK_CODE,0x80	# system damage?
759
	bo	BASED(mcck_int_main)	# yes -> rest of mcck code invalid
760
	mvc	__LC_MCCK_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA
761 762 763 764 765 766 767 768 769 770 771 772 773
	tm	__LC_MCCK_CODE+5,0x02	# stored cpu timer value valid?
	bo	BASED(1f)
	la	%r14,__LC_SYNC_ENTER_TIMER
	clc	0(8,%r14),__LC_ASYNC_ENTER_TIMER
	bl	BASED(0f)
	la	%r14,__LC_ASYNC_ENTER_TIMER
0:	clc	0(8,%r14),__LC_EXIT_TIMER
	bl	BASED(0f)
	la	%r14,__LC_EXIT_TIMER
0:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
	bl	BASED(0f)
	la	%r14,__LC_LAST_UPDATE_TIMER
0:	spt	0(%r14)
774
	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
775
1:	tm	__LC_MCCK_CODE+2,0x09	# mwp + ia of old psw valid?
776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791
	bno	BASED(mcck_int_main)	# no -> skip cleanup critical
	tm	__LC_MCK_OLD_PSW+1,0x01	# test problem state bit
	bnz	BASED(mcck_int_main)	# from user -> load async stack
	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_end)
	bhe	BASED(mcck_int_main)
	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_start)
	bl	BASED(mcck_int_main)
	l	%r14,BASED(.Lcleanup_critical)
	basr	%r14,%r14
mcck_int_main:
	l	%r14,__LC_PANIC_STACK	# are we already on the panic stack?
	slr	%r14,%r15
	sra	%r14,PAGE_SHIFT
	be	BASED(0f)
	l	%r15,__LC_PANIC_STACK	# load panic stack
0:	CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+32
Heiko Carstens's avatar
Heiko Carstens committed
792
	tm	__LC_MCCK_CODE+2,0x08	# mwp of old psw valid?
793
	bno	BASED(mcck_no_vtime)	# no -> skip cleanup critical
794
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
795
	bz	BASED(mcck_no_vtime)
796
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_MCCK_ENTER_TIMER,__LC_USER_TIMER
797
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
798
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_MCCK_ENTER_TIMER
799
mcck_no_vtime:
800 801
	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Heiko Carstens's avatar
Heiko Carstens committed
802 803 804
	l	%r1,BASED(.Ls390_mcck)
	basr	%r14,%r1		# call machine check handler
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
805
	bno	BASED(mcck_return)
Heiko Carstens's avatar
Heiko Carstens committed
806
	l	%r1,__LC_KERNEL_STACK	# switch to kernel stack
807 808
	s	%r1,BASED(.Lc_spsize)
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
809
	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
810 811 812 813
	lr	%r15,%r1
	stosm	__SF_EMPTY(%r15),0x04	# turn dat on
	tm	__TI_flags+3(%r9),_TIF_MCCK_PENDING
	bno	BASED(mcck_return)
814
	TRACE_IRQS_OFF
815 816
	l	%r1,BASED(.Ls390_handle_mcck)
	basr	%r14,%r1		# call machine check handler
817
	TRACE_IRQS_ON
Linus Torvalds's avatar
Linus Torvalds committed
818
mcck_return:
819 820 821 822 823 824 825
	mvc	__LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW
	ni	__LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
	bno	BASED(0f)
	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
	stpt	__LC_EXIT_TIMER
	lpsw	__LC_RETURN_MCCK_PSW	# back to caller
826
0:	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
827 828
	lpsw	__LC_RETURN_MCCK_PSW	# back to caller

Heiko Carstens's avatar
Heiko Carstens committed
829
	RESTORE_ALL __LC_RETURN_MCCK_PSW,0
Linus Torvalds's avatar
Linus Torvalds committed
830 831 832 833

/*
 * Restart interruption handler, kick starter for additional CPUs
 */
834
#ifdef CONFIG_SMP
835
	__CPUINIT
Heiko Carstens's avatar
Heiko Carstens committed
836
	.globl restart_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
837
restart_int_handler:
838 839 840 841 842 843
	basr	%r1,0
restart_base:
	spt	restart_vtime-restart_base(%r1)
	stck	__LC_LAST_UPDATE_CLOCK
	mvc	__LC_LAST_UPDATE_TIMER(8),restart_vtime-restart_base(%r1)
	mvc	__LC_EXIT_TIMER(8),restart_vtime-restart_base(%r1)
Heiko Carstens's avatar
Heiko Carstens committed
844 845 846 847
	l	%r15,__LC_SAVE_AREA+60	# load ksp
	lctl	%c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs
	lam	%a0,%a15,__LC_AREGS_SAVE_AREA
	lm	%r6,%r15,__SF_GPRS(%r15) # load registers from clone
848 849 850 851
	l	%r1,__LC_THREAD_INFO
	mvc	__LC_USER_TIMER(8),__TI_user_timer(%r1)
	mvc	__LC_SYSTEM_TIMER(8),__TI_system_timer(%r1)
	xc	__LC_STEAL_TIMER(8),__LC_STEAL_TIMER
Heiko Carstens's avatar
Heiko Carstens committed
852 853 854 855
	stosm	__SF_EMPTY(%r15),0x04	# now we can turn dat on
	basr	%r14,0
	l	%r14,restart_addr-.(%r14)
	br	%r14			# branch to start_secondary
Linus Torvalds's avatar
Linus Torvalds committed
856
restart_addr:
Heiko Carstens's avatar
Heiko Carstens committed
857
	.long	start_secondary
858 859 860
	.align	8
restart_vtime:
	.long	0x7fffffff,0xffffffff
861
	.previous
Linus Torvalds's avatar
Linus Torvalds committed
862 863 864 865
#else
/*
 * If we do not run with SMP enabled, let the new CPU crash ...
 */
Heiko Carstens's avatar
Heiko Carstens committed
866
	.globl restart_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
867
restart_int_handler:
Heiko Carstens's avatar
Heiko Carstens committed
868
	basr	%r1,0
Linus Torvalds's avatar
Linus Torvalds committed
869
restart_base:
Heiko Carstens's avatar
Heiko Carstens committed
870 871
	lpsw	restart_crash-restart_base(%r1)
	.align	8
Linus Torvalds's avatar
Linus Torvalds committed
872
restart_crash:
Heiko Carstens's avatar
Heiko Carstens committed
873
	.long	0x000a0000,0x00000000
Linus Torvalds's avatar
Linus Torvalds committed
874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894
restart_go:
#endif

#ifdef CONFIG_CHECK_STACK
/*
 * The synchronous or the asynchronous stack overflowed. We are dead.
 * No need to properly save the registers, we are going to panic anyway.
 * Setup a pt_regs so that show_trace can provide a good call trace.
 */
stack_overflow:
	l	%r15,__LC_PANIC_STACK	# change to panic stack
	sl	%r15,BASED(.Lc_spsize)
	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
	la	%r1,__LC_SAVE_AREA
	ch	%r12,BASED(.L0x020)	# old psw addr == __LC_SVC_OLD_PSW ?
	be	BASED(0f)
	ch	%r12,BASED(.L0x028)	# old psw addr == __LC_PGM_OLD_PSW ?
	be	BASED(0f)
	la	%r1,__LC_SAVE_AREA+16
0:	mvc	SP_R12(16,%r15),0(%r1)	# move %r12-%r15 to stack
Heiko Carstens's avatar
Heiko Carstens committed
895
	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
896
	l	%r1,BASED(1f)		# branch to kernel_stack_overflow
Heiko Carstens's avatar
Heiko Carstens committed
897
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
898
	br	%r1
Heiko Carstens's avatar
Heiko Carstens committed
899
1:	.long	kernel_stack_overflow
Linus Torvalds's avatar
Linus Torvalds committed
900 901 902 903
#endif

cleanup_table_system_call:
	.long	system_call + 0x80000000, sysc_do_svc + 0x80000000
904 905 906 907 908 909 910 911
cleanup_table_sysc_tif:
	.long	sysc_tif + 0x80000000, sysc_restore + 0x80000000
cleanup_table_sysc_restore:
	.long	sysc_restore + 0x80000000, sysc_done + 0x80000000
cleanup_table_io_tif:
	.long	io_tif + 0x80000000, io_restore + 0x80000000
cleanup_table_io_restore:
	.long	io_restore + 0x80000000, io_done + 0x80000000
Linus Torvalds's avatar
Linus Torvalds committed
912 913 914 915 916 917 918

cleanup_critical:
	clc	4(4,%r12),BASED(cleanup_table_system_call)
	bl	BASED(0f)
	clc	4(4,%r12),BASED(cleanup_table_system_call+4)
	bl	BASED(cleanup_system_call)
0:
919
	clc	4(4,%r12),BASED(cleanup_table_sysc_tif)
Linus Torvalds's avatar
Linus Torvalds committed
920
	bl	BASED(0f)
921 922
	clc	4(4,%r12),BASED(cleanup_table_sysc_tif+4)
	bl	BASED(cleanup_sysc_tif)
Linus Torvalds's avatar
Linus Torvalds committed
923
0:
924
	clc	4(4,%r12),BASED(cleanup_table_sysc_restore)
Linus Torvalds's avatar
Linus Torvalds committed
925
	bl	BASED(0f)
926 927
	clc	4(4,%r12),BASED(cleanup_table_sysc_restore+4)
	bl	BASED(cleanup_sysc_restore)
928
0:
929
	clc	4(4,%r12),BASED(cleanup_table_io_tif)
930
	bl	BASED(0f)
931 932
	clc	4(4,%r12),BASED(cleanup_table_io_tif+4)
	bl	BASED(cleanup_io_tif)
933
0:
934
	clc	4(4,%r12),BASED(cleanup_table_io_restore)
935
	bl	BASED(0f)
936 937
	clc	4(4,%r12),BASED(cleanup_table_io_restore+4)
	bl	BASED(cleanup_io_restore)
Linus Torvalds's avatar
Linus Torvalds committed
938 939 940 941 942 943 944
0:
	br	%r14

cleanup_system_call:
	mvc	__LC_RETURN_PSW(8),0(%r12)
	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4)
	bh	BASED(0f)
945 946 947
	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
	c	%r12,BASED(.Lmck_old_psw)
	be	BASED(0f)
Linus Torvalds's avatar
Linus Torvalds committed
948
	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
949 950 951 952
0:	c	%r12,BASED(.Lmck_old_psw)
	la	%r12,__LC_SAVE_AREA+32
	be	BASED(0f)
	la	%r12,__LC_SAVE_AREA+16
Linus Torvalds's avatar
Linus Torvalds committed
953 954 955 956
0:	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+8)
	bhe	BASED(cleanup_vtime)
	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn)
	bh	BASED(0f)
957 958 959
	mvc	__LC_SAVE_AREA(16),0(%r12)
0:	st	%r13,4(%r12)
	st	%r12,__LC_SAVE_AREA+48	# argh
960
	SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
961
	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
962 963
	l	%r12,__LC_SAVE_AREA+48	# argh
	st	%r15,12(%r12)
Linus Torvalds's avatar
Linus Torvalds committed
964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979
	lh	%r7,0x8a
cleanup_vtime:
	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
	bhe	BASED(cleanup_stime)
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
cleanup_stime:
	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+16)
	bh	BASED(cleanup_update)
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
cleanup_update:
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
	mvc	__LC_RETURN_PSW+4(4),BASED(cleanup_table_system_call+4)
	la	%r12,__LC_RETURN_PSW
	br	%r14
cleanup_system_call_insn:
	.long	sysc_saveall + 0x80000000
Heiko Carstens's avatar
Heiko Carstens committed
980 981 982 983
	.long	system_call + 0x80000000
	.long	sysc_vtime + 0x80000000
	.long	sysc_stime + 0x80000000
	.long	sysc_update + 0x80000000
Linus Torvalds's avatar
Linus Torvalds committed
984

985
cleanup_sysc_tif:
Linus Torvalds's avatar
Linus Torvalds committed
986
	mvc	__LC_RETURN_PSW(4),0(%r12)