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 */
  40         llgf    %r4,__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         lghi    %r2,0
  95         lghi    %r3,2*PAGE_SIZE
  96         lghi    %r5,2*PAGE_SIZE
  97 1:      mvcle   %r2,%r4,0
  98         jo      1b
  99
 100         /* Save image */
 101         brasl   %r14,swsusp_save
 102
 103         /* Restore prefix register and return */
 104         lghi    %r1,0x1000
 105         spx     0x318(%r1)
 106         lmg     %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
 107         lghi    %r2,0
 108         br      %r14
 109
 110 /*
 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.
 114  */
 115 ENTRY(swsusp_arch_resume)
 116         stmg    %r6,%r15,__SF_GPRS(%r15)
 117         lgr     %r1,%r15
 118         aghi    %r15,-STACK_FRAME_OVERHEAD
 119         stg     %r1,__SF_BACKCHAIN(%r15)
 120
 121         /* Make all free pages stable */
 122         lghi    %r2,1
 123         brasl   %r14,arch_set_page_states
 124
 125         /* Deactivate DAT */
 126         stnsm   __SF_EMPTY(%r15),0xfb
 127
 128         /* Set prefix page to zero */
 129         xc      __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
 130         spx     __SF_EMPTY(%r15)
 131
 132         /* Restore saved image */
 133         larl    %r1,restore_pblist
 134         lg      %r1,0(%r1)
 135         ltgr    %r1,%r1
 136         jz      2f
 137 0:
 138         lg      %r2,8(%r1)
 139         lg      %r4,0(%r1)
 140         iske    %r0,%r4
 141         lghi    %r3,PAGE_SIZE
 142         lghi    %r5,PAGE_SIZE
 143 1:
 144         mvcle   %r2,%r4,0
 145         jo      1b
 146         lg      %r2,8(%r1)
 147         sske    %r0,%r2
 148         lg      %r1,16(%r1)
 149         ltgr    %r1,%r1
 150         jnz     0b
 151 2:
 152         ptlb                            /* flush tlb */
 153
 154         /* Reset System */
 155         larl    %r1,restart_entry
 156         larl    %r2,.Lrestart_diag308_psw
 157         og      %r1,0(%r2)
 158         stg     %r1,0(%r0)
 159         larl    %r1,.Lnew_pgm_check_psw
 160         epsw    %r2,%r3
 161         stm     %r2,%r3,0(%r1)
 162         mvc     __LC_PGM_NEW_PSW(16,%r0),0(%r1)
 163         lghi    %r0,0
 164         diag    %r0,%r0,0x308
 165 restart_entry:
 166         lhi     %r1,1
 167         sigp    %r1,%r0,SIGP_SET_ARCHITECTURE
 168         sam64
 169         larl    %r1,.Lnew_pgm_check_psw
 170         lpswe   0(%r1)
 171 pgm_check_entry:
 172
 173         /* Switch to original suspend CPU */
 174         larl    %r1,.Lresume_cpu                /* Resume CPU address: r2 */
 175         stap    0(%r1)
 176         llgh    %r2,0(%r1)
 177         llgh    %r1,__LC_EXT_CPU_ADDR(%r0)      /* Suspend CPU address: r1 */
 178         cgr     %r1,%r2
 179         je      restore_registers               /* r1 = r2 -> nothing to do */
 180         larl    %r4,.Lrestart_suspend_psw       /* Set new restart PSW */
 181         mvc     __LC_RST_NEW_PSW(16,%r0),0(%r4)
 182 3:
 183         sigp    %r9,%r1,SIGP_INITIAL_CPU_RESET  /* sigp initial cpu reset */
 184         brc     8,4f                            /* accepted */
 185         brc     2,3b                            /* busy, try again */
 186
 187         /* Suspend CPU not available -> panic */
 188         larl    %r15,init_thread_union
 189         ahi     %r15,1<<(PAGE_SHIFT+THREAD_ORDER)
 190         larl    %r2,.Lpanic_string
 191         larl    %r3,_sclp_print_early
 192         lghi    %r1,0
 193         sam31
 194         sigp    %r1,%r0,SIGP_SET_ARCHITECTURE
 195         basr    %r14,%r3
 196         larl    %r3,.Ldisabled_wait_31
 197         lpsw    0(%r3)
 198 4:
 199         /* Switch to suspend CPU */
 200         sigp    %r9,%r1,SIGP_RESTART    /* sigp restart to suspend CPU */
 201         brc     2,4b                    /* busy, try again */
 202 5:
 203         sigp    %r9,%r2,SIGP_STOP       /* sigp stop to current resume CPU */
 204         brc     2,5b                    /* busy, try again */
 205 6:      j       6b
 206
 207 restart_suspend:
 208         larl    %r1,.Lresume_cpu
 209         llgh    %r2,0(%r1)
 210 7:
 211         sigp    %r9,%r2,SIGP_SENSE      /* sigp sense, wait for resume CPU */
 212         brc     8,7b                    /* accepted, status 0, still running */
 213         brc     2,7b                    /* busy, try again */
 214         tmll    %r9,0x40                /* Test if resume CPU is stopped */
 215         jz      7b
 216
 217 restore_registers:
 218         /* Restore registers */
 219         lghi    %r13,0x1000             /* %r1 = pointer to save area */
 220
 221         /* Ignore time spent in suspended state. */
 222         llgf    %r1,0x318(%r13)
 223         stck    __LC_LAST_UPDATE_CLOCK(%r1)
 224         spt     0x328(%r13)             /* reprogram timer */
 225         //sckc  0x330(%r13)             /* set clock comparator */
 226
 227         lctlg   %c0,%c15,0x380(%r13)    /* load control registers */
 228         lam     %a0,%a15,0x340(%r13)    /* load access registers */
 229
 230         lfpc    0x31c(%r13)             /* load fpu control */
 231         ld      0,0x200(%r13)           /* load f0 */
 232         ld      1,0x208(%r13)           /* load f1 */
 233         ld      2,0x210(%r13)           /* load f2 */
 234         ld      3,0x218(%r13)           /* load f3 */
 235         ld      4,0x220(%r13)           /* load f4 */
 236         ld      5,0x228(%r13)           /* load f5 */
 237         ld      6,0x230(%r13)           /* load f6 */
 238         ld      7,0x238(%r13)           /* load f7 */
 239         ld      8,0x240(%r13)           /* load f8 */
 240         ld      9,0x248(%r13)           /* load f9 */
 241         ld      10,0x250(%r13)          /* load f10 */
 242         ld      11,0x258(%r13)          /* load f11 */
 243         ld      12,0x260(%r13)          /* load f12 */
 244         ld      13,0x268(%r13)          /* load f13 */
 245         ld      14,0x270(%r13)          /* load f14 */
 246         ld      15,0x278(%r13)          /* load f15 */
 247
 248         /* Load old stack */
 249         lg      %r15,0x2f8(%r13)
 250
 251         /* Restore prefix register */
 252         spx     0x318(%r13)
 253
 254         /* Activate DAT */
 255         stosm   __SF_EMPTY(%r15),0x04
 256
 257         /* Make all free pages unstable */
 258         lghi    %r2,0
 259         brasl   %r14,arch_set_page_states
 260
 261         /* Log potential guest relocation */
 262         brasl   %r14,lgr_info_log
 263
 264         /* Reinitialize the channel subsystem */
 265         brasl   %r14,channel_subsystem_reinit
 266
 267         /* Return 0 */
 268         lmg     %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
 269         lghi    %r2,0
 270         br      %r14
 271
 272         .section .data..nosave,"aw",@progbits
 273         .align  8
 274 .Ldisabled_wait_31:
 275         .long  0x000a0000,0x00000000
 276 .Lpanic_string:
 277         .asciz  "Resume not possible because suspend CPU is no longer available"
 278         .align  8
 279 .Lrestart_diag308_psw:
 280         .long   0x00080000,0x80000000
 281 .Lrestart_suspend_psw:
 282         .quad   0x0000000180000000,restart_suspend
 283 .Lnew_pgm_check_psw:
 284         .quad   0,pgm_check_entry
 285 .Lresume_cpu:
 286         .byte   0,0