[net-next-2.6.git] / arch / s390 / kernel / early.c

/*
 *  arch/s390/kernel/early.c
 *
 *    Copyright IBM Corp. 2007
 *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
 */

#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 <asm/ipl.h>
#include <asm/lowcore.h>
#include <asm/processor.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/cpcmd.h>
#include <asm/sclp.h>

/*
 * 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) {
		kernel_nss_name[0] = '\0';
		return;
	}

	__cpcmd(savesys_cmd, NULL, 0, &response);

	if (response != strlen(savesys_cmd)) {
		kernel_nss_name[0] = '\0';
		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;
			if (memsize && addr >= memsize)
				break;
#ifndef CONFIG_64BIT
			if (addr == ADDR2G)
				break;
#endif
			cc = __tprot(addr);
		}

		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_read_info_early();
	sclp_facilities_detect();
	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();
}
Commit	Line	Data
ab14de6c HC	1	/*
	2	* arch/s390/kernel/early.c
	3	*
	4	* Copyright IBM Corp. 2007
	5	* Author(s): Hongjie Yang <hongjie@us.ibm.com>,
	6	* Heiko Carstens <heiko.carstens@de.ibm.com>
	7	*/
	8
	9	#include <linux/init.h>
	10	#include <linux/errno.h>
	11	#include <linux/string.h>
	12	#include <linux/ctype.h>
	13	#include <linux/lockdep.h>
	14	#include <linux/module.h>
	15	#include <linux/pfn.h>
	16	#include <linux/uaccess.h>
46b05d26	17	#include <asm/ipl.h>
ab14de6c HC	18	#include <asm/lowcore.h>
	19	#include <asm/processor.h>
	20	#include <asm/sections.h>
	21	#include <asm/setup.h>
	22	#include <asm/cpcmd.h>
	23	#include <asm/sclp.h>
	24
	25	/*
	26	* Create a Kernel NSS if the SAVESYS= parameter is defined
	27	*/
	28	#define DEFSYS_CMD_SIZE 96
	29	#define SAVESYS_CMD_SIZE 32
	30
ab14de6c HC	31	char kernel_nss_name[NSS_NAME_SIZE + 1];
	32
	33	#ifdef CONFIG_SHARED_KERNEL
	34	static noinline __init void create_kernel_nss(void)
	35	{
	36	unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
	37	#ifdef CONFIG_BLK_DEV_INITRD
	38	unsigned int sinitrd_pfn, einitrd_pfn;
	39	#endif
	40	int response;
	41	char *savesys_ptr;
	42	char upper_command_line[COMMAND_LINE_SIZE];
	43	char defsys_cmd[DEFSYS_CMD_SIZE];
	44	char savesys_cmd[SAVESYS_CMD_SIZE];
	45
	46	/* Do nothing if we are not running under VM */
	47	if (!MACHINE_IS_VM)
	48	return;
	49
	50	/* Convert COMMAND_LINE to upper case */
	51	for (i = 0; i < strlen(COMMAND_LINE); i++)
	52	upper_command_line[i] = toupper(COMMAND_LINE[i]);
	53
	54	savesys_ptr = strstr(upper_command_line, "SAVESYS=");
	55
	56	if (!savesys_ptr)
	57	return;
	58
	59	savesys_ptr += 8; /* Point to the beginning of the NSS name */
	60	for (i = 0; i < NSS_NAME_SIZE; i++) {
	61	if (savesys_ptr[i] == ' ' \|\| savesys_ptr[i] == '\0')
	62	break;
	63	kernel_nss_name[i] = savesys_ptr[i];
	64	}
	65
	66	stext_pfn = PFN_DOWN(__pa(&_stext));
	67	eshared_pfn = PFN_DOWN(__pa(&_eshared));
	68	end_pfn = PFN_UP(__pa(&_end));
	69	min_size = end_pfn << 2;
	70
	71	sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
	72	kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
	73	eshared_pfn, end_pfn);
	74
	75	#ifdef CONFIG_BLK_DEV_INITRD
	76	if (INITRD_START && INITRD_SIZE) {
	77	sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
	78	einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
	79	min_size = einitrd_pfn << 2;
	80	sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
	81	sinitrd_pfn, einitrd_pfn);
	82	}
	83	#endif
	84
	85	sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK", defsys_cmd, min_size);
	86	sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
	87	kernel_nss_name, kernel_nss_name);
	88
	89	__cpcmd(defsys_cmd, NULL, 0, &response);
	90
583b33bc HY	91	if (response != 0) {
583b33bc HY	92	kernel_nss_name[0] = '\0';
ab14de6c	93	return;
583b33bc	94	}
ab14de6c HC	95
	96	__cpcmd(savesys_cmd, NULL, 0, &response);
	97
583b33bc HY	98	if (response != strlen(savesys_cmd)) {
583b33bc HY	99	kernel_nss_name[0] = '\0';
ab14de6c	100	return;
583b33bc	101	}
ab14de6c HC	102
	103	ipl_flags = IPL_NSS_VALID;
	104	}
	105
	106	#else /* CONFIG_SHARED_KERNEL */
	107
	108	static inline void create_kernel_nss(void) { }
	109
	110	#endif /* CONFIG_SHARED_KERNEL */
	111
	112	/*
	113	* Clear bss memory
	114	*/
	115	static noinline __init void clear_bss_section(void)
	116	{
229d9c6d	117	memset(__bss_start, 0, __bss_stop - __bss_start);
ab14de6c HC	118	}
	119
	120	/*
	121	* Initialize storage key for kernel pages
	122	*/
	123	static noinline __init void init_kernel_storage_key(void)
	124	{
	125	unsigned long end_pfn, init_pfn;
	126
	127	end_pfn = PFN_UP(__pa(&_end));
	128
	129	for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
	130	page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
	131	}
	132
	133	static noinline __init void detect_machine_type(void)
	134	{
	135	struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
	136
72960a02	137	get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
ab14de6c HC	138
	139	/* Running under z/VM ? */
	140	if (cpuinfo->cpu_id.version == 0xff)
	141	machine_flags \|= 1;
	142
	143	/* Running on a P/390 ? */
	144	if (cpuinfo->cpu_id.machine == 0x7490)
	145	machine_flags \|= 4;
	146	}
	147
257c6e1c	148	#ifdef CONFIG_64BIT
ab14de6c HC	149	static noinline __init int memory_fast_detect(void)
ab14de6c HC	150	{
ab14de6c HC	151	unsigned long val0 = 0;
	152	unsigned long val1 = 0xc;
	153	int ret = -ENOSYS;
	154
	155	if (ipl_flags & IPL_NSS_VALID)
	156	return -ENOSYS;
	157
	158	asm volatile(
	159	" diag %1,%2,0x260\n"
	160	"0: lhi %0,0\n"
	161	"1:\n"
	162	EX_TABLE(0b,1b)
	163	: "+d" (ret), "+d" (val0), "+d" (val1) : : "cc");
	164
	165	if (ret \|\| val0 != val1)
	166	return -ENOSYS;
	167
257c6e1c	168	memory_chunk[0].size = val0 + 1;
ab14de6c HC	169	return 0;
ab14de6c HC	170	}
257c6e1c HC	171	#else
	172	static inline int memory_fast_detect(void)
	173	{
	174	return -ENOSYS;
	175	}
	176	#endif
ab14de6c	177
ab14de6c HC	178	static inline __init unsigned long __tprot(unsigned long addr)
	179	{
	180	int cc = -1;
	181
	182	asm volatile(
	183	" tprot 0(%1),0\n"
	184	"0: ipm %0\n"
	185	" srl %0,28\n"
	186	"1:\n"
	187	EX_TABLE(0b,1b)
	188	: "+d" (cc) : "a" (addr) : "cc");
	189	return (unsigned long)cc;
	190	}
	191
	192	/* Checking memory in 128KB increments. */
	193	#define CHUNK_INCR (1UL << 17)
05dd2530	194	#define ADDR2G (1UL << 31)
ab14de6c HC	195
	196	static noinline __init void find_memory_chunks(unsigned long memsize)
	197	{
	198	unsigned long addr = 0, old_addr = 0;
	199	unsigned long old_cc = CHUNK_READ_WRITE;
	200	unsigned long cc;
	201	int chunk = 0;
	202
	203	while (chunk < MEMORY_CHUNKS) {
	204	cc = __tprot(addr);
	205	while (cc == old_cc) {
	206	addr += CHUNK_INCR;
a2cb0737	207	if (memsize && addr >= memsize)
0b8da654	208	break;
ab14de6c HC	209	#ifndef CONFIG_64BIT
	210	if (addr == ADDR2G)
	211	break;
	212	#endif
0b8da654	213	cc = __tprot(addr);
ab14de6c HC	214	}
	215
	216	if (old_addr != addr &&
	217	(old_cc == CHUNK_READ_WRITE \|\| old_cc == CHUNK_READ_ONLY)) {
	218	memory_chunk[chunk].addr = old_addr;
	219	memory_chunk[chunk].size = addr - old_addr;
	220	memory_chunk[chunk].type = old_cc;
	221	chunk++;
	222	}
	223
	224	old_addr = addr;
	225	old_cc = cc;
	226
	227	#ifndef CONFIG_64BIT
	228	if (addr == ADDR2G)
	229	break;
	230	#endif
	231	/*
29c380f5 HC	232	* Finish memory detection at the first hole
29c380f5 HC	233	* if storage size is unknown.
ab14de6c	234	*/
29c380f5	235	if (cc == -1UL && !memsize)
ab14de6c HC	236	break;
	237	if (memsize && addr >= memsize)
	238	break;
	239	}
	240	}
	241
	242	static __init void early_pgm_check_handler(void)
	243	{
	244	unsigned long addr;
	245	const struct exception_table_entry *fixup;
	246
	247	addr = S390_lowcore.program_old_psw.addr;
	248	fixup = search_exception_tables(addr & PSW_ADDR_INSN);
	249	if (!fixup)
	250	disabled_wait(0);
	251	S390_lowcore.program_old_psw.addr = fixup->fixup \| PSW_ADDR_AMODE;
	252	}
	253
	254	static noinline __init void setup_lowcore_early(void)
	255	{
	256	psw_t psw;
	257
	258	psw.mask = PSW_BASE_BITS \| PSW_DEFAULT_KEY;
	259	psw.addr = PSW_ADDR_AMODE \| (unsigned long) s390_base_ext_handler;
	260	S390_lowcore.external_new_psw = psw;
	261	psw.addr = PSW_ADDR_AMODE \| (unsigned long) s390_base_pgm_handler;
	262	S390_lowcore.program_new_psw = psw;
	263	s390_base_pgm_handler_fn = early_pgm_check_handler;
	264	}
	265
	266	/*
	267	* Save ipl parameters, clear bss memory, initialize storage keys
	268	* and create a kernel NSS at startup if the SAVESYS= parm is defined
	269	*/
	270	void __init startup_init(void)
	271	{
05dd2530	272	unsigned long long memsize;
ab14de6c HC	273
	274	ipl_save_parameters();
	275	clear_bss_section();
	276	init_kernel_storage_key();
	277	lockdep_init();
	278	lockdep_off();
	279	detect_machine_type();
	280	create_kernel_nss();
	281	sort_main_extable();
	282	setup_lowcore_early();
08d07968	283	sclp_read_info_early();
83119ad4	284	sclp_facilities_detect();
ab14de6c	285	memsize = sclp_memory_detect();
05dd2530 HC	286	#ifndef CONFIG_64BIT
	287	/*
	288	* Can't deal with more than 2G in 31 bit addressing mode, so
	289	* limit the value in order to avoid strange side effects.
	290	*/
	291	if (memsize > ADDR2G)
	292	memsize = ADDR2G;
	293	#endif
ab14de6c	294	if (memory_fast_detect() < 0)
05dd2530	295	find_memory_chunks((unsigned long) memsize);
ab14de6c HC	296	lockdep_on();
ab14de6c HC	297	}