diff options
Diffstat (limited to 'arch/s390/kernel/early.c')
| -rw-r--r-- | arch/s390/kernel/early.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c new file mode 100644 index 000000000..ad88bed74 --- /dev/null +++ b/arch/s390/kernel/early.c @@ -0,0 +1,366 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright IBM Corp. 2007, 2009 + * Author(s): Hongjie Yang <hongjie@us.ibm.com>, + * Heiko Carstens <heiko.carstens@de.ibm.com> + */ + +#define KMSG_COMPONENT "setup" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/compiler.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/ctype.h> +#include <linux/lockdep.h> +#include <linux/extable.h> +#include <linux/pfn.h> +#include <linux/uaccess.h> +#include <linux/kernel.h> +#include <asm/diag.h> +#include <asm/ebcdic.h> +#include <asm/ipl.h> +#include <asm/lowcore.h> +#include <asm/processor.h> +#include <asm/sections.h> +#include <asm/setup.h> +#include <asm/sysinfo.h> +#include <asm/cpcmd.h> +#include <asm/sclp.h> +#include <asm/facility.h> +#include "entry.h" + +static void __init setup_boot_command_line(void); + +/* + * Initialize storage key for kernel pages + */ +static noinline __init void init_kernel_storage_key(void) +{ +#if PAGE_DEFAULT_KEY + 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, 0); +#endif +} + +static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE); + +static noinline __init void detect_machine_type(void) +{ + struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page; + + /* Check current-configuration-level */ + if (stsi(NULL, 0, 0, 0) <= 2) { + S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR; + return; + } + /* Get virtual-machine cpu information. */ + if (stsi(vmms, 3, 2, 2) || !vmms->count) + return; + + /* Detect known hypervisors */ + if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3)) + S390_lowcore.machine_flags |= MACHINE_FLAG_KVM; + else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4)) + S390_lowcore.machine_flags |= MACHINE_FLAG_VM; +} + +/* Remove leading, trailing and double whitespace. */ +static inline void strim_all(char *str) +{ + char *s; + + s = strim(str); + if (s != str) + memmove(str, s, strlen(s)); + while (*str) { + if (!isspace(*str++)) + continue; + if (isspace(*str)) { + s = skip_spaces(str); + memmove(str, s, strlen(s) + 1); + } + } +} + +static noinline __init void setup_arch_string(void) +{ + struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page; + struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page; + char mstr[80], hvstr[17]; + + if (stsi(mach, 1, 1, 1)) + return; + EBCASC(mach->manufacturer, sizeof(mach->manufacturer)); + EBCASC(mach->type, sizeof(mach->type)); + EBCASC(mach->model, sizeof(mach->model)); + EBCASC(mach->model_capacity, sizeof(mach->model_capacity)); + sprintf(mstr, "%-16.16s %-4.4s %-16.16s %-16.16s", + mach->manufacturer, mach->type, + mach->model, mach->model_capacity); + strim_all(mstr); + if (stsi(vm, 3, 2, 2) == 0 && vm->count) { + EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi)); + sprintf(hvstr, "%-16.16s", vm->vm[0].cpi); + strim_all(hvstr); + } else { + sprintf(hvstr, "%s", + MACHINE_IS_LPAR ? "LPAR" : + MACHINE_IS_VM ? "z/VM" : + MACHINE_IS_KVM ? "KVM" : "unknown"); + } + dump_stack_set_arch_desc("%s (%s)", mstr, hvstr); +} + +static __init void setup_topology(void) +{ + int max_mnest; + + if (!test_facility(11)) + return; + S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY; + for (max_mnest = 6; max_mnest > 1; max_mnest--) { + if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0) + break; + } + topology_max_mnest = max_mnest; +} + +static void early_pgm_check_handler(void) +{ + const struct exception_table_entry *fixup; + unsigned long cr0, cr0_new; + unsigned long addr; + + addr = S390_lowcore.program_old_psw.addr; + fixup = search_exception_tables(addr); + if (!fixup) + disabled_wait(0); + /* Disable low address protection before storing into lowcore. */ + __ctl_store(cr0, 0, 0); + cr0_new = cr0 & ~(1UL << 28); + __ctl_load(cr0_new, 0, 0); + S390_lowcore.program_old_psw.addr = extable_fixup(fixup); + __ctl_load(cr0, 0, 0); +} + +static noinline __init void setup_lowcore_early(void) +{ + psw_t psw; + + psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA; + if (IS_ENABLED(CONFIG_KASAN)) + psw.mask |= PSW_MASK_DAT; + psw.addr = (unsigned long) s390_base_ext_handler; + S390_lowcore.external_new_psw = psw; + psw.addr = (unsigned long) s390_base_pgm_handler; + S390_lowcore.program_new_psw = psw; + s390_base_pgm_handler_fn = early_pgm_check_handler; + S390_lowcore.preempt_count = INIT_PREEMPT_COUNT; +} + +static noinline __init void setup_facility_list(void) +{ + stfle(S390_lowcore.stfle_fac_list, + ARRAY_SIZE(S390_lowcore.stfle_fac_list)); + memcpy(S390_lowcore.alt_stfle_fac_list, + S390_lowcore.stfle_fac_list, + sizeof(S390_lowcore.alt_stfle_fac_list)); + if (!IS_ENABLED(CONFIG_KERNEL_NOBP)) + __clear_facility(82, S390_lowcore.alt_stfle_fac_list); +} + +static __init void detect_diag9c(void) +{ + unsigned int cpu_address; + int rc; + + cpu_address = stap(); + diag_stat_inc(DIAG_STAT_X09C); + asm volatile( + " diag %2,0,0x9c\n" + "0: la %0,0\n" + "1:\n" + EX_TABLE(0b,1b) + : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc"); + if (!rc) + S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C; +} + +static __init void detect_diag44(void) +{ + int rc; + + diag_stat_inc(DIAG_STAT_X044); + asm volatile( + " diag 0,0,0x44\n" + "0: la %0,0\n" + "1:\n" + EX_TABLE(0b,1b) + : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc"); + if (!rc) + S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44; +} + +static __init void detect_machine_facilities(void) +{ + if (test_facility(8)) { + S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1; + __ctl_set_bit(0, 23); + } + if (test_facility(78)) + S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2; + if (test_facility(3)) + S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE; + if (test_facility(50) && test_facility(73)) { + S390_lowcore.machine_flags |= MACHINE_FLAG_TE; + __ctl_set_bit(0, 55); + } + if (test_facility(51)) + S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC; + if (test_facility(129)) { + S390_lowcore.machine_flags |= MACHINE_FLAG_VX; + __ctl_set_bit(0, 17); + } + if (test_facility(130)) { + S390_lowcore.machine_flags |= MACHINE_FLAG_NX; + __ctl_set_bit(0, 20); + } + if (test_facility(133)) + S390_lowcore.machine_flags |= MACHINE_FLAG_GS; + if (test_facility(139) && (tod_clock_base[1] & 0x80)) { + /* Enabled signed clock comparator comparisons */ + S390_lowcore.machine_flags |= MACHINE_FLAG_SCC; + clock_comparator_max = -1ULL >> 1; + __ctl_set_bit(0, 53); + } +} + +static inline void save_vector_registers(void) +{ +#ifdef CONFIG_CRASH_DUMP + if (test_facility(129)) + save_vx_regs(boot_cpu_vector_save_area); +#endif +} + +static int __init disable_vector_extension(char *str) +{ + S390_lowcore.machine_flags &= ~MACHINE_FLAG_VX; + __ctl_clear_bit(0, 17); + return 0; +} +early_param("novx", disable_vector_extension); + +static int __init noexec_setup(char *str) +{ + bool enabled; + int rc; + + rc = kstrtobool(str, &enabled); + if (!rc && !enabled) { + /* Disable no-execute support */ + S390_lowcore.machine_flags &= ~MACHINE_FLAG_NX; + __ctl_clear_bit(0, 20); + } + return rc; +} +early_param("noexec", noexec_setup); + +static int __init cad_setup(char *str) +{ + bool enabled; + int rc; + + rc = kstrtobool(str, &enabled); + if (!rc && enabled && test_facility(128)) + /* Enable problem state CAD. */ + __ctl_set_bit(2, 3); + return rc; +} +early_param("cad", cad_setup); + +/* Set up boot command line */ +static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t)) +{ + char *parm, *delim; + size_t rc, len; + + len = strlen(boot_command_line); + + delim = boot_command_line + len; /* '\0' character position */ + parm = boot_command_line + len + 1; /* append right after '\0' */ + + rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1); + if (rc) { + if (*parm == '=') + memmove(boot_command_line, parm + 1, rc); + else + *delim = ' '; /* replace '\0' with space */ + } +} + +static inline int has_ebcdic_char(const char *str) +{ + int i; + + for (i = 0; str[i]; i++) + if (str[i] & 0x80) + return 1; + return 0; +} + +static void __init setup_boot_command_line(void) +{ + COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0; + /* convert arch command line to ascii if necessary */ + if (has_ebcdic_char(COMMAND_LINE)) + EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE); + /* copy arch command line */ + strlcpy(boot_command_line, strstrip(COMMAND_LINE), + ARCH_COMMAND_LINE_SIZE); + + /* append IPL PARM data to the boot command line */ + if (MACHINE_IS_VM) + append_to_cmdline(append_ipl_vmparm); + + append_to_cmdline(append_ipl_scpdata); +} + +static void __init check_image_bootable(void) +{ + if (!memcmp(EP_STRING, (void *)EP_OFFSET, strlen(EP_STRING))) + return; + + sclp_early_printk("Linux kernel boot failure: An attempt to boot a vmlinux ELF image failed.\n"); + sclp_early_printk("This image does not contain all parts necessary for starting up. Use\n"); + sclp_early_printk("bzImage or arch/s390/boot/compressed/vmlinux instead.\n"); + disabled_wait(0xbadb007); +} + +void __init startup_init(void) +{ + check_image_bootable(); + time_early_init(); + init_kernel_storage_key(); + lockdep_off(); + setup_lowcore_early(); + setup_facility_list(); + detect_machine_type(); + setup_arch_string(); + ipl_store_parameters(); + setup_boot_command_line(); + detect_diag9c(); + detect_diag44(); + detect_machine_facilities(); + save_vector_registers(); + setup_topology(); + sclp_early_detect(); + lockdep_on(); +} |