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-rw-r--r--arch/s390/kernel/suspend.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/arch/s390/kernel/suspend.c b/arch/s390/kernel/suspend.c
new file mode 100644
index 00000000000..086bee970ca
--- /dev/null
+++ b/arch/s390/kernel/suspend.c
@@ -0,0 +1,73 @@
+/*
+ * Suspend support specific for s390.
+ *
+ * Copyright IBM Corp. 2009
+ *
+ * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com>
+ */
+
+#include <linux/suspend.h>
+#include <linux/reboot.h>
+#include <linux/pfn.h>
+#include <linux/mm.h>
+#include <asm/sections.h>
+#include <asm/system.h>
+#include <asm/ipl.h>
+
+/*
+ * References to section boundaries
+ */
+extern const void __nosave_begin, __nosave_end;
+
+/*
+ * check if given pfn is in the 'nosave' or in the read only NSS section
+ */
+int pfn_is_nosave(unsigned long pfn)
+{
+ unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
+ unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end))
+ >> PAGE_SHIFT;
+ unsigned long eshared_pfn = PFN_DOWN(__pa(&_eshared)) - 1;
+ unsigned long stext_pfn = PFN_DOWN(__pa(&_stext));
+
+ if (pfn >= nosave_begin_pfn && pfn < nosave_end_pfn)
+ return 1;
+ if (pfn >= stext_pfn && pfn <= eshared_pfn) {
+ if (ipl_info.type == IPL_TYPE_NSS)
+ return 1;
+ } else if ((tprot(pfn * PAGE_SIZE) && pfn > 0))
+ return 1;
+ return 0;
+}
+
+void save_processor_state(void)
+{
+ /* swsusp_arch_suspend() actually saves all cpu register contents.
+ * Machine checks must be disabled since swsusp_arch_suspend() stores
+ * register contents to their lowcore save areas. That's the same
+ * place where register contents on machine checks would be saved.
+ * To avoid register corruption disable machine checks.
+ * We must also disable machine checks in the new psw mask for
+ * program checks, since swsusp_arch_suspend() may generate program
+ * checks. Disabling machine checks for all other new psw masks is
+ * just paranoia.
+ */
+ local_mcck_disable();
+ /* Disable lowcore protection */
+ __ctl_clear_bit(0,28);
+ S390_lowcore.external_new_psw.mask &= ~PSW_MASK_MCHECK;
+ S390_lowcore.svc_new_psw.mask &= ~PSW_MASK_MCHECK;
+ S390_lowcore.io_new_psw.mask &= ~PSW_MASK_MCHECK;
+ S390_lowcore.program_new_psw.mask &= ~PSW_MASK_MCHECK;
+}
+
+void restore_processor_state(void)
+{
+ S390_lowcore.external_new_psw.mask |= PSW_MASK_MCHECK;
+ S390_lowcore.svc_new_psw.mask |= PSW_MASK_MCHECK;
+ S390_lowcore.io_new_psw.mask |= PSW_MASK_MCHECK;
+ S390_lowcore.program_new_psw.mask |= PSW_MASK_MCHECK;
+ /* Enable lowcore protection */
+ __ctl_set_bit(0,28);
+ local_mcck_enable();
+}