1 files changed, 444 insertions, 0 deletions
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
new file mode 100644
index 000000000..549a73a4b
--- /dev/null
+++ b/arch/s390/kernel/early.c
@@ -0,0 +1,444 @@
+/*
+ *    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/module.h>
+#include <linux/pfn.h>
+#include <linux/uaccess.h>
+#include <linux/kernel.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"
+
+/*
+ * Create a Kernel NSS if the SAVESYS= parameter is defined
+ */
+#define DEFSYS_CMD_SIZE		128
+#define SAVESYS_CMD_SIZE	32
+
+char kernel_nss_name[NSS_NAME_SIZE + 1];
+
+static void __init setup_boot_command_line(void);
+
+/*
+ * Get the TOD clock running.
+ */
+static void __init reset_tod_clock(void)
+{
+	u64 time;
+
+	if (store_tod_clock(&time) == 0)
+		return;
+	/* TOD clock not running. Set the clock to Unix Epoch. */
+	if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0)
+		disabled_wait(0);
+
+	sched_clock_base_cc = TOD_UNIX_EPOCH;
+	S390_lowcore.last_update_clock = sched_clock_base_cc;
+}
+
+#ifdef CONFIG_SHARED_KERNEL
+int __init savesys_ipl_nss(char *cmd, const int cmdlen);
+
+asm(
+	"	.section .init.text,\"ax\",@progbits\n"
+	"	.align	4\n"
+	"	.type	savesys_ipl_nss, @function\n"
+	"savesys_ipl_nss:\n"
+	"	stmg	6,15,48(15)\n"
+	"	lgr	14,3\n"
+	"	sam31\n"
+	"	diag	2,14,0x8\n"
+	"	sam64\n"
+	"	lgr	2,14\n"
+	"	lmg	6,15,48(15)\n"
+	"	br	14\n"
+	"	.size	savesys_ipl_nss, .-savesys_ipl_nss\n"
+	"	.previous\n");
+
+static __initdata char upper_command_line[COMMAND_LINE_SIZE];
+
+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;
+	int hlen;
+	size_t len;
+	char *savesys_ptr;
+	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(boot_command_line); i++)
+		upper_command_line[i] = toupper(boot_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;
+
+	hlen = snprintf(defsys_cmd, DEFSYS_CMD_SIZE,
+			"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;
+		hlen += snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
+				 " EW %.5X-%.5X", sinitrd_pfn, einitrd_pfn);
+	}
+#endif
+
+	snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
+		 " EW MINSIZE=%.7iK PARMREGS=0-13", min_size);
+	defsys_cmd[DEFSYS_CMD_SIZE - 1] = '\0';
+	snprintf(savesys_cmd, SAVESYS_CMD_SIZE, "SAVESYS %s \n IPL %s",
+		 kernel_nss_name, kernel_nss_name);
+	savesys_cmd[SAVESYS_CMD_SIZE - 1] = '\0';
+
+	__cpcmd(defsys_cmd, NULL, 0, &response);
+
+	if (response != 0) {
+		pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
+			response);
+		kernel_nss_name[0] = '\0';
+		return;
+	}
+
+	len = strlen(savesys_cmd);
+	ASCEBC(savesys_cmd, len);
+	response = savesys_ipl_nss(savesys_cmd, len);
+
+	/* On success: response is equal to the command size,
+	 *	       max SAVESYS_CMD_SIZE
+	 * On error: response contains the numeric portion of cp error message.
+	 *	     for SAVESYS it will be >= 263
+	 *	     for missing privilege class, it will be 1
+	 */
+	if (response > SAVESYS_CMD_SIZE || response == 1) {
+		pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
+			response);
+		kernel_nss_name[0] = '\0';
+		return;
+	}
+
+	/* re-initialize cputime accounting. */
+	sched_clock_base_cc = get_tod_clock();
+	S390_lowcore.last_update_clock = sched_clock_base_cc;
+	S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
+	S390_lowcore.user_timer = 0;
+	S390_lowcore.system_timer = 0;
+	asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
+
+	/* re-setup boot command line with new ipl vm parms */
+	ipl_update_parameters();
+	setup_boot_command_line();
+
+	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)
+{
+#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;
+}
+
+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 & PSW_ADDR_INSN);
+	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)|PSW_ADDR_AMODE;
+	__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 = 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;
+}
+
+static noinline __init void setup_facility_list(void)
+{
+	stfle(S390_lowcore.stfle_fac_list,
+	      ARRAY_SIZE(S390_lowcore.stfle_fac_list));
+}
+
+static __init void detect_diag9c(void)
+{
+	unsigned int cpu_address;
+	int rc;
+
+	cpu_address = stap();
+	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;
+
+	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(40))
+		S390_lowcore.machine_flags |= MACHINE_FLAG_LPP;
+	if (test_facility(50) && test_facility(73))
+		S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
+	if (test_facility(51))
+		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
+	if (test_facility(129))
+		S390_lowcore.machine_flags |= MACHINE_FLAG_VX;
+}
+
+static int __init cad_setup(char *str)
+{
+	int val;
+
+	get_option(&str, &val);
+	if (val && test_facility(128))
+		S390_lowcore.machine_flags |= MACHINE_FLAG_CAD;
+	return 0;
+}
+early_param("cad", cad_setup);
+
+static int __init cad_init(void)
+{
+	if (MACHINE_HAS_CAD)
+		/* Enable problem state CAD. */
+		__ctl_set_bit(2, 3);
+	return 0;
+}
+early_initcall(cad_init);
+
+static __init void rescue_initrd(void)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+	unsigned long min_initrd_addr = (unsigned long) _end + (4UL << 20);
+	/*
+	 * Just like in case of IPL from VM reader we make sure there is a
+	 * gap of 4MB between end of kernel and start of initrd.
+	 * That way we can also be sure that saving an NSS will succeed,
+	 * which however only requires different segments.
+	 */
+	if (!INITRD_START || !INITRD_SIZE)
+		return;
+	if (INITRD_START >= min_initrd_addr)
+		return;
+	memmove((void *) min_initrd_addr, (void *) INITRD_START, INITRD_SIZE);
+	INITRD_START = min_initrd_addr;
+#endif
+}
+
+/* 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);
+}
+
+/*
+ * 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)
+{
+	reset_tod_clock();
+	ipl_save_parameters();
+	rescue_initrd();
+	clear_bss_section();
+	init_kernel_storage_key();
+	lockdep_init();
+	lockdep_off();
+	setup_lowcore_early();
+	setup_facility_list();
+	detect_machine_type();
+	ipl_update_parameters();
+	setup_boot_command_line();
+	create_kernel_nss();
+	detect_diag9c();
+	detect_diag44();
+	detect_machine_facilities();
+	setup_topology();
+	sclp_early_detect();
+	lockdep_on();
+}