2 * S390 64-bit swsusp implementation
4 * Copyright IBM Corp. 2009
6 * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com>
7 * Michael Holzheu <holzheu@linux.vnet.ibm.com>
10 #include <linux/linkage.h>
12 #include <asm/ptrace.h>
13 #include <asm/thread_info.h>
14 #include <asm/asm-offsets.h>
15 #include <asm/nospec-insn.h>
19 * Save register context in absolute 0 lowcore and call swsusp_save() to
20 * create in-memory kernel image. The context is saved in the designated
21 * "store status" memory locations (see POP).
22 * We return from this function twice. The first time during the suspend to
23 * disk process. The second time via the swsusp_arch_resume() function
24 * (see below) in the resume process.
25 * This function runs with disabled interrupts.
30 ENTRY(swsusp_arch_suspend)
31 stmg %r6,%r15,__SF_GPRS(%r15)
33 aghi %r15,-STACK_FRAME_OVERHEAD
34 stg %r1,__SF_BACKCHAIN(%r15)
36 /* Store FPU registers */
37 brasl %r14,save_fpu_regs
40 stnsm __SF_EMPTY(%r15),0xfb
42 /* Store prefix register on stack */
45 /* Save prefix register contents for lowcore copy */
46 llgf %r10,__SF_EMPTY(%r15)
48 /* Get pointer to save area */
51 /* Save CPU address */
52 stap __LC_EXT_CPU_ADDR(%r0)
55 mvc 0x318(4,%r1),__SF_EMPTY(%r15) /* move prefix to lowcore */
56 stam %a0,%a15,0x340(%r1) /* store access registers */
57 stctg %c0,%c15,0x380(%r1) /* store control registers */
58 stmg %r0,%r15,0x280(%r1) /* store general registers */
60 stpt 0x328(%r1) /* store timer */
61 stck __SF_EMPTY(%r15) /* store clock */
62 stckc 0x330(%r1) /* store clock comparator */
64 /* Update cputime accounting before going to sleep */
65 lg %r0,__LC_LAST_UPDATE_TIMER
67 alg %r0,__LC_SYSTEM_TIMER
68 stg %r0,__LC_SYSTEM_TIMER
69 mvc __LC_LAST_UPDATE_TIMER(8),0x328(%r1)
70 lg %r0,__LC_LAST_UPDATE_CLOCK
71 slg %r0,__SF_EMPTY(%r15)
72 alg %r0,__LC_STEAL_TIMER
73 stg %r0,__LC_STEAL_TIMER
74 mvc __LC_LAST_UPDATE_CLOCK(8),__SF_EMPTY(%r15)
77 stosm __SF_EMPTY(%r15),0x04
79 /* Set prefix page to zero */
80 xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
83 /* Save absolute zero pages */
84 larl %r2,suspend_zero_pages
92 /* Copy lowcore to absolute zero lowcore */
101 brasl %r14,swsusp_save
103 /* Restore prefix register and return */
106 lmg %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
111 * Restore saved memory image to correct place and restore register context.
112 * Then we return to the function that called swsusp_arch_suspend().
113 * swsusp_arch_resume() runs with disabled interrupts.
115 ENTRY(swsusp_arch_resume)
116 stmg %r6,%r15,__SF_GPRS(%r15)
118 aghi %r15,-STACK_FRAME_OVERHEAD
119 stg %r1,__SF_BACKCHAIN(%r15)
121 /* Make all free pages stable */
123 brasl %r14,arch_set_page_states
126 stnsm __SF_EMPTY(%r15),0xfb
128 /* Set prefix page to zero */
129 xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
132 /* Restore saved image */
133 larl %r1,restore_pblist
155 larl %r1,restart_entry
156 larl %r2,.Lrestart_diag308_psw
159 larl %r1,.Lnew_pgm_check_psw
162 mvc __LC_PGM_NEW_PSW(16,%r0),0(%r1)
167 sigp %r1,%r0,SIGP_SET_ARCHITECTURE
170 larl %r1,smp_cpu_mt_shift
175 sigp %r1,%r0,SIGP_SET_MULTI_THREADING
176 brc 8,smt_done /* accepted */
177 brc 2,smt_loop /* busy, try again */
180 larl %r1,.Lnew_pgm_check_psw
184 /* Switch to original suspend CPU */
185 larl %r1,.Lresume_cpu /* Resume CPU address: r2 */
188 llgh %r1,__LC_EXT_CPU_ADDR(%r0) /* Suspend CPU address: r1 */
190 je restore_registers /* r1 = r2 -> nothing to do */
191 larl %r4,.Lrestart_suspend_psw /* Set new restart PSW */
192 mvc __LC_RST_NEW_PSW(16,%r0),0(%r4)
194 sigp %r9,%r1,SIGP_INITIAL_CPU_RESET /* sigp initial cpu reset */
195 brc 8,4f /* accepted */
196 brc 2,3b /* busy, try again */
198 /* Suspend CPU not available -> panic */
199 larl %r15,init_thread_union
200 ahi %r15,1<<(PAGE_SHIFT+THREAD_ORDER)
201 larl %r2,.Lpanic_string
202 larl %r3,_sclp_print_early
205 sigp %r1,%r0,SIGP_SET_ARCHITECTURE
206 brasl %r14,_sclp_print_early
207 larl %r3,.Ldisabled_wait_31
210 /* Switch to suspend CPU */
211 sigp %r9,%r1,SIGP_RESTART /* sigp restart to suspend CPU */
212 brc 2,4b /* busy, try again */
214 sigp %r9,%r2,SIGP_STOP /* sigp stop to current resume CPU */
215 brc 2,5b /* busy, try again */
219 larl %r1,.Lresume_cpu
222 sigp %r9,%r2,SIGP_SENSE /* sigp sense, wait for resume CPU */
223 brc 8,7b /* accepted, status 0, still running */
224 brc 2,7b /* busy, try again */
225 tmll %r9,0x40 /* Test if resume CPU is stopped */
229 /* Restore registers */
230 lghi %r13,0x1000 /* %r1 = pointer to save area */
232 /* Ignore time spent in suspended state. */
234 stck __LC_LAST_UPDATE_CLOCK(%r1)
235 spt 0x328(%r13) /* reprogram timer */
236 //sckc 0x330(%r13) /* set clock comparator */
238 lctlg %c0,%c15,0x380(%r13) /* load control registers */
239 lam %a0,%a15,0x340(%r13) /* load access registers */
244 /* Save prefix register */
245 mvc __SF_EMPTY(4,%r15),0x318(%r13)
247 /* Restore absolute zero pages */
249 larl %r4,suspend_zero_pages
256 /* Restore prefix register */
260 stosm __SF_EMPTY(%r15),0x04
262 /* Make all free pages unstable */
264 brasl %r14,arch_set_page_states
266 /* Call arch specific early resume code */
267 brasl %r14,s390_early_resume
270 lmg %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
274 .section .data..nosave,"aw",@progbits
277 .long 0x000a0000,0x00000000
279 .asciz "Resume not possible because suspend CPU is no longer available"
281 .Lrestart_diag308_psw:
282 .long 0x00080000,0x80000000
283 .Lrestart_suspend_psw:
284 .quad 0x0000000180000000,restart_suspend
286 .quad 0,pgm_check_entry