| 1 | /* |
| 2 | * Suspend support specific for s390. |
| 3 | * |
| 4 | * Copyright IBM Corp. 2009 |
| 5 | * |
| 6 | * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/suspend.h> |
| 10 | #include <linux/reboot.h> |
| 11 | #include <linux/pfn.h> |
| 12 | #include <linux/mm.h> |
| 13 | #include <asm/sections.h> |
| 14 | #include <asm/system.h> |
| 15 | #include <asm/ipl.h> |
| 16 | |
| 17 | /* |
| 18 | * References to section boundaries |
| 19 | */ |
| 20 | extern const void __nosave_begin, __nosave_end; |
| 21 | |
| 22 | /* |
| 23 | * check if given pfn is in the 'nosave' or in the read only NSS section |
| 24 | */ |
| 25 | int pfn_is_nosave(unsigned long pfn) |
| 26 | { |
| 27 | unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT; |
| 28 | unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) |
| 29 | >> PAGE_SHIFT; |
| 30 | unsigned long eshared_pfn = PFN_DOWN(__pa(&_eshared)) - 1; |
| 31 | unsigned long stext_pfn = PFN_DOWN(__pa(&_stext)); |
| 32 | |
| 33 | if (pfn >= nosave_begin_pfn && pfn < nosave_end_pfn) |
| 34 | return 1; |
| 35 | if (pfn >= stext_pfn && pfn <= eshared_pfn) { |
| 36 | if (ipl_info.type == IPL_TYPE_NSS) |
| 37 | return 1; |
| 38 | } else if ((tprot(pfn * PAGE_SIZE) && pfn > 0)) |
| 39 | return 1; |
| 40 | return 0; |
| 41 | } |
| 42 | |
| 43 | void save_processor_state(void) |
| 44 | { |
| 45 | /* swsusp_arch_suspend() actually saves all cpu register contents. |
| 46 | * Machine checks must be disabled since swsusp_arch_suspend() stores |
| 47 | * register contents to their lowcore save areas. That's the same |
| 48 | * place where register contents on machine checks would be saved. |
| 49 | * To avoid register corruption disable machine checks. |
| 50 | * We must also disable machine checks in the new psw mask for |
| 51 | * program checks, since swsusp_arch_suspend() may generate program |
| 52 | * checks. Disabling machine checks for all other new psw masks is |
| 53 | * just paranoia. |
| 54 | */ |
| 55 | local_mcck_disable(); |
| 56 | /* Disable lowcore protection */ |
| 57 | __ctl_clear_bit(0,28); |
| 58 | S390_lowcore.external_new_psw.mask &= ~PSW_MASK_MCHECK; |
| 59 | S390_lowcore.svc_new_psw.mask &= ~PSW_MASK_MCHECK; |
| 60 | S390_lowcore.io_new_psw.mask &= ~PSW_MASK_MCHECK; |
| 61 | S390_lowcore.program_new_psw.mask &= ~PSW_MASK_MCHECK; |
| 62 | } |
| 63 | |
| 64 | void restore_processor_state(void) |
| 65 | { |
| 66 | S390_lowcore.external_new_psw.mask |= PSW_MASK_MCHECK; |
| 67 | S390_lowcore.svc_new_psw.mask |= PSW_MASK_MCHECK; |
| 68 | S390_lowcore.io_new_psw.mask |= PSW_MASK_MCHECK; |
| 69 | S390_lowcore.program_new_psw.mask |= PSW_MASK_MCHECK; |
| 70 | /* Enable lowcore protection */ |
| 71 | __ctl_set_bit(0,28); |
| 72 | local_mcck_enable(); |
| 73 | } |