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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/s390/kernel/swsusp.S
Initial import
Diffstat (limited to 'arch/s390/kernel/swsusp.S')
-rw-r--r--arch/s390/kernel/swsusp.S317
1 files changed, 317 insertions, 0 deletions
diff --git a/arch/s390/kernel/swsusp.S b/arch/s390/kernel/swsusp.S
new file mode 100644
index 000000000..ca6294645
--- /dev/null
+++ b/arch/s390/kernel/swsusp.S
@@ -0,0 +1,317 @@
+/*
+ * 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/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.
+ */
+ .section .text
+ENTRY(swsusp_arch_suspend)
+ stmg %r6,%r15,__SF_GPRS(%r15)
+ lgr %r1,%r15
+ aghi %r15,-STACK_FRAME_OVERHEAD
+ stg %r1,__SF_BACKCHAIN(%r15)
+
+ /* 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 */
+ stfpc 0x31c(%r1) /* store fpu control */
+ std 0,0x200(%r1) /* store f0 */
+ std 1,0x208(%r1) /* store f1 */
+ std 2,0x210(%r1) /* store f2 */
+ std 3,0x218(%r1) /* store f3 */
+ std 4,0x220(%r1) /* store f4 */
+ std 5,0x228(%r1) /* store f5 */
+ std 6,0x230(%r1) /* store f6 */
+ std 7,0x238(%r1) /* store f7 */
+ std 8,0x240(%r1) /* store f8 */
+ std 9,0x248(%r1) /* store f9 */
+ std 10,0x250(%r1) /* store f10 */
+ std 11,0x258(%r1) /* store f11 */
+ std 12,0x260(%r1) /* store f12 */
+ std 13,0x268(%r1) /* store f13 */
+ std 14,0x270(%r1) /* store f14 */
+ std 15,0x278(%r1) /* store f15 */
+ 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 %r14
+
+/*
+ * 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
+
+ /* Deactivate DAT */
+ stnsm __SF_EMPTY(%r15),0xfb
+
+ /* Set prefix page to zero */
+ xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
+ spx __SF_EMPTY(%r15)
+
+ /* 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,restart_entry
+ larl %r2,.Lrestart_diag308_psw
+ og %r1,0(%r2)
+ stg %r1,0(%r0)
+ larl %r1,.Lnew_pgm_check_psw
+ epsw %r2,%r3
+ stm %r2,%r3,0(%r1)
+ mvc __LC_PGM_NEW_PSW(16,%r0),0(%r1)
+ lghi %r0,0
+ diag %r0,%r0,0x308
+restart_entry:
+ lhi %r1,1
+ sigp %r1,%r0,SIGP_SET_ARCHITECTURE
+ sam64
+#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
+ ahi %r15,1<<(PAGE_SHIFT+THREAD_ORDER)
+ larl %r2,.Lpanic_string
+ larl %r3,_sclp_print_early
+ lghi %r1,0
+ sam31
+ sigp %r1,%r0,SIGP_SET_ARCHITECTURE
+ basr %r14,%r3
+ 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 */
+
+ lfpc 0x31c(%r13) /* load fpu control */
+ ld 0,0x200(%r13) /* load f0 */
+ ld 1,0x208(%r13) /* load f1 */
+ ld 2,0x210(%r13) /* load f2 */
+ ld 3,0x218(%r13) /* load f3 */
+ ld 4,0x220(%r13) /* load f4 */
+ ld 5,0x228(%r13) /* load f5 */
+ ld 6,0x230(%r13) /* load f6 */
+ ld 7,0x238(%r13) /* load f7 */
+ ld 8,0x240(%r13) /* load f8 */
+ ld 9,0x248(%r13) /* load f9 */
+ ld 10,0x250(%r13) /* load f10 */
+ ld 11,0x258(%r13) /* load f11 */
+ ld 12,0x260(%r13) /* load f12 */
+ ld 13,0x268(%r13) /* load f13 */
+ ld 14,0x270(%r13) /* load f14 */
+ ld 15,0x278(%r13) /* load f15 */
+
+ /* 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 %r14
+
+ .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"
+ .align 8
+.Lrestart_diag308_psw:
+ .long 0x00080000,0x80000000
+.Lrestart_suspend_psw:
+ .quad 0x0000000180000000,restart_suspend
+.Lnew_pgm_check_psw:
+ .quad 0,pgm_check_entry
+.Lresume_cpu:
+ .byte 0,0