| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * S390 64-bit swsusp implementation |
| * |
| * Copyright IBM Corp. 2009 |
| * |
| * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com> |
| * Michael Holzheu <holzheu@linux.vnet.ibm.com> |
| */ |
| |
| #include <linux/linkage.h> |
| #include <asm/page.h> |
| #include <asm/ptrace.h> |
| #include <asm/thread_info.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/nospec-insn.h> |
| #include <asm/sigp.h> |
| |
| /* |
| * Save register context in absolute 0 lowcore and call swsusp_save() to |
| * create in-memory kernel image. The context is saved in the designated |
| * "store status" memory locations (see POP). |
| * We return from this function twice. The first time during the suspend to |
| * disk process. The second time via the swsusp_arch_resume() function |
| * (see below) in the resume process. |
| * This function runs with disabled interrupts. |
| */ |
| GEN_BR_THUNK %r14 |
| |
| .section .text |
| ENTRY(swsusp_arch_suspend) |
| lg %r1,__LC_NODAT_STACK |
| stmg %r6,%r15,__SF_GPRS(%r1) |
| aghi %r1,-STACK_FRAME_OVERHEAD |
| stg %r15,__SF_BACKCHAIN(%r1) |
| lgr %r15,%r1 |
| |
| /* Store FPU registers */ |
| brasl %r14,save_fpu_regs |
| |
| /* Deactivate DAT */ |
| stnsm __SF_EMPTY(%r15),0xfb |
| |
| /* Store prefix register on stack */ |
| stpx __SF_EMPTY(%r15) |
| |
| /* Save prefix register contents for lowcore copy */ |
| llgf %r10,__SF_EMPTY(%r15) |
| |
| /* Get pointer to save area */ |
| lghi %r1,0x1000 |
| |
| /* Save CPU address */ |
| stap __LC_EXT_CPU_ADDR(%r0) |
| |
| /* Store registers */ |
| mvc 0x318(4,%r1),__SF_EMPTY(%r15) /* move prefix to lowcore */ |
| stam %a0,%a15,0x340(%r1) /* store access registers */ |
| stctg %c0,%c15,0x380(%r1) /* store control registers */ |
| stmg %r0,%r15,0x280(%r1) /* store general registers */ |
| |
| stpt 0x328(%r1) /* store timer */ |
| stck __SF_EMPTY(%r15) /* store clock */ |
| stckc 0x330(%r1) /* store clock comparator */ |
| |
| /* Update cputime accounting before going to sleep */ |
| lg %r0,__LC_LAST_UPDATE_TIMER |
| slg %r0,0x328(%r1) |
| alg %r0,__LC_SYSTEM_TIMER |
| stg %r0,__LC_SYSTEM_TIMER |
| mvc __LC_LAST_UPDATE_TIMER(8),0x328(%r1) |
| lg %r0,__LC_LAST_UPDATE_CLOCK |
| slg %r0,__SF_EMPTY(%r15) |
| alg %r0,__LC_STEAL_TIMER |
| stg %r0,__LC_STEAL_TIMER |
| mvc __LC_LAST_UPDATE_CLOCK(8),__SF_EMPTY(%r15) |
| |
| /* Activate DAT */ |
| stosm __SF_EMPTY(%r15),0x04 |
| |
| /* Set prefix page to zero */ |
| xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15) |
| spx __SF_EMPTY(%r15) |
| |
| /* Save absolute zero pages */ |
| larl %r2,suspend_zero_pages |
| lg %r2,0(%r2) |
| lghi %r4,0 |
| lghi %r3,2*PAGE_SIZE |
| lghi %r5,2*PAGE_SIZE |
| 1: mvcle %r2,%r4,0 |
| jo 1b |
| |
| /* Copy lowcore to absolute zero lowcore */ |
| lghi %r2,0 |
| lgr %r4,%r10 |
| lghi %r3,2*PAGE_SIZE |
| lghi %r5,2*PAGE_SIZE |
| 1: mvcle %r2,%r4,0 |
| jo 1b |
| |
| /* Save image */ |
| brasl %r14,swsusp_save |
| |
| /* Restore prefix register and return */ |
| lghi %r1,0x1000 |
| spx 0x318(%r1) |
| lmg %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15) |
| lghi %r2,0 |
| BR_EX %r14 |
| ENDPROC(swsusp_arch_suspend) |
| |
| /* |
| * Restore saved memory image to correct place and restore register context. |
| * Then we return to the function that called swsusp_arch_suspend(). |
| * swsusp_arch_resume() runs with disabled interrupts. |
| */ |
| ENTRY(swsusp_arch_resume) |
| stmg %r6,%r15,__SF_GPRS(%r15) |
| lgr %r1,%r15 |
| aghi %r15,-STACK_FRAME_OVERHEAD |
| stg %r1,__SF_BACKCHAIN(%r15) |
| |
| /* Make all free pages stable */ |
| lghi %r2,1 |
| brasl %r14,arch_set_page_states |
| |
| /* Set prefix page to zero */ |
| xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15) |
| spx __SF_EMPTY(%r15) |
| |
| /* Deactivate DAT */ |
| stnsm __SF_EMPTY(%r15),0xfb |
| |
| /* Restore saved image */ |
| larl %r1,restore_pblist |
| lg %r1,0(%r1) |
| ltgr %r1,%r1 |
| jz 2f |
| 0: |
| lg %r2,8(%r1) |
| lg %r4,0(%r1) |
| iske %r0,%r4 |
| lghi %r3,PAGE_SIZE |
| lghi %r5,PAGE_SIZE |
| 1: |
| mvcle %r2,%r4,0 |
| jo 1b |
| lg %r2,8(%r1) |
| sske %r0,%r2 |
| lg %r1,16(%r1) |
| ltgr %r1,%r1 |
| jnz 0b |
| 2: |
| ptlb /* flush tlb */ |
| |
| /* Reset System */ |
| larl %r1,.Lnew_pgm_check_psw |
| epsw %r2,%r3 |
| stm %r2,%r3,0(%r1) |
| mvc __LC_PGM_NEW_PSW(16,%r0),0(%r1) |
| larl %r1,__swsusp_reset_dma |
| lg %r1,0(%r1) |
| BASR_EX %r14,%r1 |
| #ifdef CONFIG_SMP |
| larl %r1,smp_cpu_mt_shift |
| icm %r1,15,0(%r1) |
| jz smt_done |
| llgfr %r1,%r1 |
| smt_loop: |
| sigp %r1,%r0,SIGP_SET_MULTI_THREADING |
| brc 8,smt_done /* accepted */ |
| brc 2,smt_loop /* busy, try again */ |
| smt_done: |
| #endif |
| larl %r1,.Lnew_pgm_check_psw |
| lpswe 0(%r1) |
| pgm_check_entry: |
| |
| /* Switch to original suspend CPU */ |
| larl %r1,.Lresume_cpu /* Resume CPU address: r2 */ |
| stap 0(%r1) |
| llgh %r2,0(%r1) |
| llgh %r1,__LC_EXT_CPU_ADDR(%r0) /* Suspend CPU address: r1 */ |
| cgr %r1,%r2 |
| je restore_registers /* r1 = r2 -> nothing to do */ |
| larl %r4,.Lrestart_suspend_psw /* Set new restart PSW */ |
| mvc __LC_RST_NEW_PSW(16,%r0),0(%r4) |
| 3: |
| sigp %r9,%r1,SIGP_INITIAL_CPU_RESET /* sigp initial cpu reset */ |
| brc 8,4f /* accepted */ |
| brc 2,3b /* busy, try again */ |
| |
| /* Suspend CPU not available -> panic */ |
| larl %r15,init_thread_union+THREAD_SIZE-STACK_FRAME_OVERHEAD |
| larl %r2,.Lpanic_string |
| brasl %r14,sclp_early_printk_force |
| larl %r3,.Ldisabled_wait_31 |
| lpsw 0(%r3) |
| 4: |
| /* Switch to suspend CPU */ |
| sigp %r9,%r1,SIGP_RESTART /* sigp restart to suspend CPU */ |
| brc 2,4b /* busy, try again */ |
| 5: |
| sigp %r9,%r2,SIGP_STOP /* sigp stop to current resume CPU */ |
| brc 2,5b /* busy, try again */ |
| 6: j 6b |
| |
| restart_suspend: |
| larl %r1,.Lresume_cpu |
| llgh %r2,0(%r1) |
| 7: |
| sigp %r9,%r2,SIGP_SENSE /* sigp sense, wait for resume CPU */ |
| brc 8,7b /* accepted, status 0, still running */ |
| brc 2,7b /* busy, try again */ |
| tmll %r9,0x40 /* Test if resume CPU is stopped */ |
| jz 7b |
| |
| restore_registers: |
| /* Restore registers */ |
| lghi %r13,0x1000 /* %r1 = pointer to save area */ |
| |
| /* Ignore time spent in suspended state. */ |
| llgf %r1,0x318(%r13) |
| stck __LC_LAST_UPDATE_CLOCK(%r1) |
| spt 0x328(%r13) /* reprogram timer */ |
| //sckc 0x330(%r13) /* set clock comparator */ |
| |
| lctlg %c0,%c15,0x380(%r13) /* load control registers */ |
| lam %a0,%a15,0x340(%r13) /* load access registers */ |
| |
| /* Load old stack */ |
| lg %r15,0x2f8(%r13) |
| |
| /* Save prefix register */ |
| mvc __SF_EMPTY(4,%r15),0x318(%r13) |
| |
| /* Restore absolute zero pages */ |
| lghi %r2,0 |
| larl %r4,suspend_zero_pages |
| lg %r4,0(%r4) |
| lghi %r3,2*PAGE_SIZE |
| lghi %r5,2*PAGE_SIZE |
| 1: mvcle %r2,%r4,0 |
| jo 1b |
| |
| /* Restore prefix register */ |
| spx __SF_EMPTY(%r15) |
| |
| /* Activate DAT */ |
| stosm __SF_EMPTY(%r15),0x04 |
| |
| /* Make all free pages unstable */ |
| lghi %r2,0 |
| brasl %r14,arch_set_page_states |
| |
| /* Call arch specific early resume code */ |
| brasl %r14,s390_early_resume |
| |
| /* Return 0 */ |
| lmg %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15) |
| lghi %r2,0 |
| BR_EX %r14 |
| ENDPROC(swsusp_arch_resume) |
| |
| .section .data..nosave,"aw",@progbits |
| .align 8 |
| .Ldisabled_wait_31: |
| .long 0x000a0000,0x00000000 |
| .Lpanic_string: |
| .asciz "Resume not possible because suspend CPU is no longer available\n" |
| .align 8 |
| .Lrestart_suspend_psw: |
| .quad 0x0000000180000000,restart_suspend |
| .Lnew_pgm_check_psw: |
| .quad 0,pgm_check_entry |
| .Lresume_cpu: |
| .byte 0,0 |
