arch/s390/kernel/swsusp_asm64.S

   1 /*
   2  * S390 64-bit swsusp implementation
   3  *
   4  * Copyright IBM Corp. 2009
   5  *
   6  * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com>
   7  *            Michael Holzheu <holzheu@linux.vnet.ibm.com>
   8  */
   9
  10 #include <linux/linkage.h>
  11 #include <asm/page.h>
  12 #include <asm/ptrace.h>
  13 #include <asm/thread_info.h>
  14 #include <asm/asm-offsets.h>
  15 #include <asm/sigp.h>
  16
  17 /*
  18  * Save register context in absolute 0 lowcore and call swsusp_save() to
  19  * create in-memory kernel image. The context is saved in the designated
  20  * "store status" memory locations (see POP).
  21  * We return from this function twice. The first time during the suspend to
  22  * disk process. The second time via the swsusp_arch_resume() function
  23  * (see below) in the resume process.
  24  * This function runs with disabled interrupts.
  25  */
  26         .section .text
  27 ENTRY(swsusp_arch_suspend)
  28         stmg    %r6,%r15,__SF_GPRS(%r15)
  29         lgr     %r1,%r15
  30         aghi    %r15,-STACK_FRAME_OVERHEAD
  31         stg     %r1,__SF_BACKCHAIN(%r15)
  32
  33         /* Deactivate DAT */
  34         stnsm   __SF_EMPTY(%r15),0xfb
  35
  36         /* Store prefix register on stack */
  37         stpx    __SF_EMPTY(%r15)
  38
  39         /* Save prefix register contents for lowcore copy */
  40         llgf    %r10,__SF_EMPTY(%r15)
  41
  42         /* Get pointer to save area */
  43         lghi    %r1,0x1000
  44
  45         /* Save CPU address */
  46         stap    __LC_EXT_CPU_ADDR(%r0)
  47
  48         /* Store registers */
  49         mvc     0x318(4,%r1),__SF_EMPTY(%r15)   /* move prefix to lowcore */
  50         stfpc   0x31c(%r1)                      /* store fpu control */
  51         std     0,0x200(%r1)                    /* store f0 */
  52         std     1,0x208(%r1)                    /* store f1 */
  53         std     2,0x210(%r1)                    /* store f2 */
  54         std     3,0x218(%r1)                    /* store f3 */
  55         std     4,0x220(%r1)                    /* store f4 */
  56         std     5,0x228(%r1)                    /* store f5 */
  57         std     6,0x230(%r1)                    /* store f6 */
  58         std     7,0x238(%r1)                    /* store f7 */
  59         std     8,0x240(%r1)                    /* store f8 */
  60         std     9,0x248(%r1)                    /* store f9 */
  61         std     10,0x250(%r1)                   /* store f10 */
  62         std     11,0x258(%r1)                   /* store f11 */
  63         std     12,0x260(%r1)                   /* store f12 */
  64         std     13,0x268(%r1)                   /* store f13 */
  65         std     14,0x270(%r1)                   /* store f14 */
  66         std     15,0x278(%r1)                   /* store f15 */
  67         stam    %a0,%a15,0x340(%r1)             /* store access registers */
  68         stctg   %c0,%c15,0x380(%r1)             /* store control registers */
  69         stmg    %r0,%r15,0x280(%r1)             /* store general registers */
  70
  71         stpt    0x328(%r1)                      /* store timer */
  72         stck    __SF_EMPTY(%r15)                /* store clock */
  73         stckc   0x330(%r1)                      /* store clock comparator */
  74
  75         /* Update cputime accounting before going to sleep */
  76         lg      %r0,__LC_LAST_UPDATE_TIMER
  77         slg     %r0,0x328(%r1)
  78         alg     %r0,__LC_SYSTEM_TIMER
  79         stg     %r0,__LC_SYSTEM_TIMER
  80         mvc     __LC_LAST_UPDATE_TIMER(8),0x328(%r1)
  81         lg      %r0,__LC_LAST_UPDATE_CLOCK
  82         slg     %r0,__SF_EMPTY(%r15)
  83         alg     %r0,__LC_STEAL_TIMER
  84         stg     %r0,__LC_STEAL_TIMER
  85         mvc     __LC_LAST_UPDATE_CLOCK(8),__SF_EMPTY(%r15)
  86
  87         /* Activate DAT */
  88         stosm   __SF_EMPTY(%r15),0x04
  89
  90         /* Set prefix page to zero */
  91         xc      __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
  92         spx     __SF_EMPTY(%r15)
  93
  94         /* Save absolute zero pages */
  95         larl    %r2,suspend_zero_pages
  96         lg      %r2,0(%r2)
  97         lghi    %r4,0
  98         lghi    %r3,2*PAGE_SIZE
  99         lghi    %r5,2*PAGE_SIZE
 100 1:      mvcle   %r2,%r4,0
 101         jo      1b
 102
 103         /* Copy lowcore to absolute zero lowcore */
 104         lghi    %r2,0
 105         lgr     %r4,%r10
 106         lghi    %r3,2*PAGE_SIZE
 107         lghi    %r5,2*PAGE_SIZE
 108 1:      mvcle   %r2,%r4,0
 109         jo      1b
 110
 111         /* Save image */
 112         brasl   %r14,swsusp_save
 113
 114         /* Restore prefix register and return */
 115         lghi    %r1,0x1000
 116         spx     0x318(%r1)
 117         lmg     %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
 118         lghi    %r2,0
 119         br      %r14
 120
 121 /*
 122  * Restore saved memory image to correct place and restore register context.
 123  * Then we return to the function that called swsusp_arch_suspend().
 124  * swsusp_arch_resume() runs with disabled interrupts.
 125  */
 126 ENTRY(swsusp_arch_resume)
 127         stmg    %r6,%r15,__SF_GPRS(%r15)
 128         lgr     %r1,%r15
 129         aghi    %r15,-STACK_FRAME_OVERHEAD
 130         stg     %r1,__SF_BACKCHAIN(%r15)
 131
 132         /* Make all free pages stable */
 133         lghi    %r2,1
 134         brasl   %r14,arch_set_page_states
 135
 136         /* Deactivate DAT */
 137         stnsm   __SF_EMPTY(%r15),0xfb
 138
 139         /* Set prefix page to zero */
 140         xc      __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
 141         spx     __SF_EMPTY(%r15)
 142
 143         /* Restore saved image */
 144         larl    %r1,restore_pblist
 145         lg      %r1,0(%r1)
 146         ltgr    %r1,%r1
 147         jz      2f
 148 0:
 149         lg      %r2,8(%r1)
 150         lg      %r4,0(%r1)
 151         iske    %r0,%r4
 152         lghi    %r3,PAGE_SIZE
 153         lghi    %r5,PAGE_SIZE
 154 1:
 155         mvcle   %r2,%r4,0
 156         jo      1b
 157         lg      %r2,8(%r1)
 158         sske    %r0,%r2
 159         lg      %r1,16(%r1)
 160         ltgr    %r1,%r1
 161         jnz     0b
 162 2:
 163         ptlb                            /* flush tlb */
 164
 165         /* Reset System */
 166         larl    %r1,restart_entry
 167         larl    %r2,.Lrestart_diag308_psw
 168         og      %r1,0(%r2)
 169         stg     %r1,0(%r0)
 170         larl    %r1,.Lnew_pgm_check_psw
 171         epsw    %r2,%r3
 172         stm     %r2,%r3,0(%r1)
 173         mvc     __LC_PGM_NEW_PSW(16,%r0),0(%r1)
 174         lghi    %r0,0
 175         diag    %r0,%r0,0x308
 176 restart_entry:
 177         lhi     %r1,1
 178         sigp    %r1,%r0,SIGP_SET_ARCHITECTURE
 179         sam64
 180 #ifdef CONFIG_SMP
 181         larl    %r1,smp_cpu_mt_shift
 182         icm     %r1,15,0(%r1)
 183         jz      smt_done
 184         llgfr   %r1,%r1
 185 smt_loop:
 186         sigp    %r1,%r0,SIGP_SET_MULTI_THREADING
 187         brc     8,smt_done                      /* accepted */
 188         brc     2,smt_loop                      /* busy, try again */
 189 smt_done:
 190 #endif
 191         larl    %r1,.Lnew_pgm_check_psw
 192         lpswe   0(%r1)
 193 pgm_check_entry:
 194
 195         /* Switch to original suspend CPU */
 196         larl    %r1,.Lresume_cpu                /* Resume CPU address: r2 */
 197         stap    0(%r1)
 198         llgh    %r2,0(%r1)
 199         llgh    %r1,__LC_EXT_CPU_ADDR(%r0)      /* Suspend CPU address: r1 */
 200         cgr     %r1,%r2
 201         je      restore_registers               /* r1 = r2 -> nothing to do */
 202         larl    %r4,.Lrestart_suspend_psw       /* Set new restart PSW */
 203         mvc     __LC_RST_NEW_PSW(16,%r0),0(%r4)
 204 3:
 205         sigp    %r9,%r1,SIGP_INITIAL_CPU_RESET  /* sigp initial cpu reset */
 206         brc     8,4f                            /* accepted */
 207         brc     2,3b                            /* busy, try again */
 208
 209         /* Suspend CPU not available -> panic */
 210         larl    %r15,init_thread_union
 211         ahi     %r15,1<<(PAGE_SHIFT+THREAD_ORDER)
 212         larl    %r2,.Lpanic_string
 213         larl    %r3,_sclp_print_early
 214         lghi    %r1,0
 215         sam31
 216         sigp    %r1,%r0,SIGP_SET_ARCHITECTURE
 217         basr    %r14,%r3
 218         larl    %r3,.Ldisabled_wait_31
 219         lpsw    0(%r3)
 220 4:
 221         /* Switch to suspend CPU */
 222         sigp    %r9,%r1,SIGP_RESTART    /* sigp restart to suspend CPU */
 223         brc     2,4b                    /* busy, try again */
 224 5:
 225         sigp    %r9,%r2,SIGP_STOP       /* sigp stop to current resume CPU */
 226         brc     2,5b                    /* busy, try again */
 227 6:      j       6b
 228
 229 restart_suspend:
 230         larl    %r1,.Lresume_cpu
 231         llgh    %r2,0(%r1)
 232 7:
 233         sigp    %r9,%r2,SIGP_SENSE      /* sigp sense, wait for resume CPU */
 234         brc     8,7b                    /* accepted, status 0, still running */
 235         brc     2,7b                    /* busy, try again */
 236         tmll    %r9,0x40                /* Test if resume CPU is stopped */
 237         jz      7b
 238
 239 restore_registers:
 240         /* Restore registers */
 241         lghi    %r13,0x1000             /* %r1 = pointer to save area */
 242
 243         /* Ignore time spent in suspended state. */
 244         llgf    %r1,0x318(%r13)
 245         stck    __LC_LAST_UPDATE_CLOCK(%r1)
 246         spt     0x328(%r13)             /* reprogram timer */
 247         //sckc  0x330(%r13)             /* set clock comparator */
 248
 249         lctlg   %c0,%c15,0x380(%r13)    /* load control registers */
 250         lam     %a0,%a15,0x340(%r13)    /* load access registers */
 251
 252         lfpc    0x31c(%r13)             /* load fpu control */
 253         ld      0,0x200(%r13)           /* load f0 */
 254         ld      1,0x208(%r13)           /* load f1 */
 255         ld      2,0x210(%r13)           /* load f2 */
 256         ld      3,0x218(%r13)           /* load f3 */
 257         ld      4,0x220(%r13)           /* load f4 */
 258         ld      5,0x228(%r13)           /* load f5 */
 259         ld      6,0x230(%r13)           /* load f6 */
 260         ld      7,0x238(%r13)           /* load f7 */
 261         ld      8,0x240(%r13)           /* load f8 */
 262         ld      9,0x248(%r13)           /* load f9 */
 263         ld      10,0x250(%r13)          /* load f10 */
 264         ld      11,0x258(%r13)          /* load f11 */
 265         ld      12,0x260(%r13)          /* load f12 */
 266         ld      13,0x268(%r13)          /* load f13 */
 267         ld      14,0x270(%r13)          /* load f14 */
 268         ld      15,0x278(%r13)          /* load f15 */
 269
 270         /* Load old stack */
 271         lg      %r15,0x2f8(%r13)
 272
 273         /* Save prefix register */
 274         mvc __SF_EMPTY(4,%r15),0x318(%r13)
 275
 276         /* Restore absolute zero pages */
 277         lghi    %r2,0
 278         larl    %r4,suspend_zero_pages
 279         lg      %r4,0(%r4)
 280         lghi    %r3,2*PAGE_SIZE
 281         lghi    %r5,2*PAGE_SIZE
 282 1:      mvcle   %r2,%r4,0
 283         jo      1b
 284
 285         /* Restore prefix register */
 286         spx     __SF_EMPTY(%r15)
 287
 288         /* Activate DAT */
 289         stosm   __SF_EMPTY(%r15),0x04
 290
 291         /* Make all free pages unstable */
 292         lghi    %r2,0
 293         brasl   %r14,arch_set_page_states
 294
 295         /* Call arch specific early resume code */
 296         brasl   %r14,s390_early_resume
 297
 298         /* Return 0 */
 299         lmg     %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
 300         lghi    %r2,0
 301         br      %r14
 302
 303         .section .data..nosave,"aw",@progbits
 304         .align  8
 305 .Ldisabled_wait_31:
 306         .long  0x000a0000,0x00000000
 307 .Lpanic_string:
 308         .asciz  "Resume not possible because suspend CPU is no longer available"
 309         .align  8
 310 .Lrestart_diag308_psw:
 311         .long   0x00080000,0x80000000
 312 .Lrestart_suspend_psw:
 313         .quad   0x0000000180000000,restart_suspend
 314 .Lnew_pgm_check_psw:
 315         .quad   0,pgm_check_entry
 316 .Lresume_cpu:
 317         .byte   0,0