arch/s390/kernel/early.c - third_party/linux - Git at Google

 // 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;

 	/* Running under KVM? If not we assume z/VM */
 	if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
 		S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
 	else
 		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;
 	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);
 }

 void __init startup_init(void)
 {
 	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();
 }
	// 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;

	/* Running under KVM? If not we assume z/VM */
	if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
	S390_lowcore.machine_flags \|= MACHINE_FLAG_KVM;
	else
	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;
	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);
	}

	void __init startup_init(void)
	{
	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();
	}