/* * arch/s390/kernel/early.c * * Copyright IBM Corp. 2007 * Author(s): Hongjie Yang , * Heiko Carstens */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Create a Kernel NSS if the SAVESYS= parameter is defined */ #define DEFSYS_CMD_SIZE 96 #define SAVESYS_CMD_SIZE 32 char kernel_nss_name[NSS_NAME_SIZE + 1]; #ifdef CONFIG_SHARED_KERNEL static noinline __init void create_kernel_nss(void) { unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size; #ifdef CONFIG_BLK_DEV_INITRD unsigned int sinitrd_pfn, einitrd_pfn; #endif int response; char *savesys_ptr; char upper_command_line[COMMAND_LINE_SIZE]; char defsys_cmd[DEFSYS_CMD_SIZE]; char savesys_cmd[SAVESYS_CMD_SIZE]; /* Do nothing if we are not running under VM */ if (!MACHINE_IS_VM) return; /* Convert COMMAND_LINE to upper case */ for (i = 0; i < strlen(COMMAND_LINE); i++) upper_command_line[i] = toupper(COMMAND_LINE[i]); savesys_ptr = strstr(upper_command_line, "SAVESYS="); if (!savesys_ptr) return; savesys_ptr += 8; /* Point to the beginning of the NSS name */ for (i = 0; i < NSS_NAME_SIZE; i++) { if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0') break; kernel_nss_name[i] = savesys_ptr[i]; } stext_pfn = PFN_DOWN(__pa(&_stext)); eshared_pfn = PFN_DOWN(__pa(&_eshared)); end_pfn = PFN_UP(__pa(&_end)); min_size = end_pfn << 2; sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X", kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1, eshared_pfn, end_pfn); #ifdef CONFIG_BLK_DEV_INITRD if (INITRD_START && INITRD_SIZE) { sinitrd_pfn = PFN_DOWN(__pa(INITRD_START)); einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE)); min_size = einitrd_pfn << 2; sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd, sinitrd_pfn, einitrd_pfn); } #endif sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK", defsys_cmd, min_size); sprintf(savesys_cmd, "SAVESYS %s \n IPL %s", kernel_nss_name, kernel_nss_name); __cpcmd(defsys_cmd, NULL, 0, &response); if (response != 0) return; __cpcmd(savesys_cmd, NULL, 0, &response); if (response != strlen(savesys_cmd)) return; ipl_flags = IPL_NSS_VALID; } #else /* CONFIG_SHARED_KERNEL */ static inline void create_kernel_nss(void) { } #endif /* CONFIG_SHARED_KERNEL */ /* * Clear bss memory */ static noinline __init void clear_bss_section(void) { memset(__bss_start, 0, __bss_stop - __bss_start); } /* * Initialize storage key for kernel pages */ static noinline __init void init_kernel_storage_key(void) { unsigned long end_pfn, init_pfn; end_pfn = PFN_UP(__pa(&_end)); for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++) page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY); } static noinline __init void detect_machine_type(void) { struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data; get_cpu_id(&S390_lowcore.cpu_data.cpu_id); /* Running under z/VM ? */ if (cpuinfo->cpu_id.version == 0xff) machine_flags |= 1; /* Running on a P/390 ? */ if (cpuinfo->cpu_id.machine == 0x7490) machine_flags |= 4; } #ifdef CONFIG_64BIT static noinline __init int memory_fast_detect(void) { unsigned long val0 = 0; unsigned long val1 = 0xc; int ret = -ENOSYS; if (ipl_flags & IPL_NSS_VALID) return -ENOSYS; asm volatile( " diag %1,%2,0x260\n" "0: lhi %0,0\n" "1:\n" EX_TABLE(0b,1b) : "+d" (ret), "+d" (val0), "+d" (val1) : : "cc"); if (ret || val0 != val1) return -ENOSYS; memory_chunk[0].size = val0 + 1; return 0; } #else static inline int memory_fast_detect(void) { return -ENOSYS; } #endif static inline __init unsigned long __tprot(unsigned long addr) { int cc = -1; asm volatile( " tprot 0(%1),0\n" "0: ipm %0\n" " srl %0,28\n" "1:\n" EX_TABLE(0b,1b) : "+d" (cc) : "a" (addr) : "cc"); return (unsigned long)cc; } /* Checking memory in 128KB increments. */ #define CHUNK_INCR (1UL << 17) #define ADDR2G (1UL << 31) static noinline __init void find_memory_chunks(unsigned long memsize) { unsigned long addr = 0, old_addr = 0; unsigned long old_cc = CHUNK_READ_WRITE; unsigned long cc; int chunk = 0; while (chunk < MEMORY_CHUNKS) { cc = __tprot(addr); while (cc == old_cc) { addr += CHUNK_INCR; cc = __tprot(addr); #ifndef CONFIG_64BIT if (addr == ADDR2G) break; #endif } if (old_addr != addr && (old_cc == CHUNK_READ_WRITE || old_cc == CHUNK_READ_ONLY)) { memory_chunk[chunk].addr = old_addr; memory_chunk[chunk].size = addr - old_addr; memory_chunk[chunk].type = old_cc; chunk++; } old_addr = addr; old_cc = cc; #ifndef CONFIG_64BIT if (addr == ADDR2G) break; #endif /* * Finish memory detection at the first hole * if storage size is unknown. */ if (cc == -1UL && !memsize) break; if (memsize && addr >= memsize) break; } } static __init void early_pgm_check_handler(void) { unsigned long addr; const struct exception_table_entry *fixup; addr = S390_lowcore.program_old_psw.addr; fixup = search_exception_tables(addr & PSW_ADDR_INSN); if (!fixup) disabled_wait(0); S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE; } static noinline __init void setup_lowcore_early(void) { psw_t psw; psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY; psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler; S390_lowcore.external_new_psw = psw; psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler; S390_lowcore.program_new_psw = psw; s390_base_pgm_handler_fn = early_pgm_check_handler; } /* * Save ipl parameters, clear bss memory, initialize storage keys * and create a kernel NSS at startup if the SAVESYS= parm is defined */ void __init startup_init(void) { unsigned long long memsize; ipl_save_parameters(); clear_bss_section(); init_kernel_storage_key(); lockdep_init(); lockdep_off(); detect_machine_type(); create_kernel_nss(); sort_main_extable(); setup_lowcore_early(); sclp_readinfo_early(); memsize = sclp_memory_detect(); #ifndef CONFIG_64BIT /* * Can't deal with more than 2G in 31 bit addressing mode, so * limit the value in order to avoid strange side effects. */ if (memsize > ADDR2G) memsize = ADDR2G; #endif if (memory_fast_detect() < 0) find_memory_chunks((unsigned long) memsize); lockdep_on(); }