[deliverable/linux.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)
		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;
			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
	91	if (response != 0)
	92	return;
	93
	94	__cpcmd(savesys_cmd, NULL, 0, &response);
95
96	if (response != strlen(savesys_cmd))
97	return;
98
99	ipl_flags = IPL_NSS_VALID;
100	}
101
102	#else /* CONFIG_SHARED_KERNEL */
103
104	static inline void create_kernel_nss(void) { }
105
106	#endif /* CONFIG_SHARED_KERNEL */
107
108	/*
109	* Clear bss memory
110	*/
111	static noinline __init void clear_bss_section(void)
112	{
229d9c6d	113	memset(__bss_start, 0, __bss_stop - __bss_start);
ab14de6c HC	114	}
	115
	116	/*
	117	* Initialize storage key for kernel pages
	118	*/
	119	static noinline __init void init_kernel_storage_key(void)
	120	{
	121	unsigned long end_pfn, init_pfn;
	122
	123	end_pfn = PFN_UP(__pa(&_end));
	124
	125	for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
	126	page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
	127	}
	128
	129	static noinline __init void detect_machine_type(void)
	130	{
	131	struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
	132
72960a02	133	get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
ab14de6c HC	134
	135	/* Running under z/VM ? */
	136	if (cpuinfo->cpu_id.version == 0xff)
	137	machine_flags \|= 1;
	138
	139	/* Running on a P/390 ? */
	140	if (cpuinfo->cpu_id.machine == 0x7490)
	141	machine_flags \|= 4;
	142	}
	143
257c6e1c	144	#ifdef CONFIG_64BIT
ab14de6c HC	145	static noinline __init int memory_fast_detect(void)
ab14de6c HC	146	{
ab14de6c HC	147	unsigned long val0 = 0;
	148	unsigned long val1 = 0xc;
	149	int ret = -ENOSYS;
	150
	151	if (ipl_flags & IPL_NSS_VALID)
	152	return -ENOSYS;
	153
	154	asm volatile(
	155	" diag %1,%2,0x260\n"
	156	"0: lhi %0,0\n"
	157	"1:\n"
	158	EX_TABLE(0b,1b)
	159	: "+d" (ret), "+d" (val0), "+d" (val1) : : "cc");
	160
	161	if (ret \|\| val0 != val1)
	162	return -ENOSYS;
	163
257c6e1c	164	memory_chunk[0].size = val0 + 1;
ab14de6c HC	165	return 0;
ab14de6c HC	166	}
257c6e1c HC	167	#else
	168	static inline int memory_fast_detect(void)
	169	{
	170	return -ENOSYS;
	171	}
	172	#endif
ab14de6c	173
ab14de6c HC	174	static inline __init unsigned long __tprot(unsigned long addr)
	175	{
	176	int cc = -1;
	177
	178	asm volatile(
	179	" tprot 0(%1),0\n"
	180	"0: ipm %0\n"
	181	" srl %0,28\n"
	182	"1:\n"
	183	EX_TABLE(0b,1b)
	184	: "+d" (cc) : "a" (addr) : "cc");
	185	return (unsigned long)cc;
	186	}
	187
	188	/* Checking memory in 128KB increments. */
	189	#define CHUNK_INCR (1UL << 17)
05dd2530	190	#define ADDR2G (1UL << 31)
ab14de6c HC	191
	192	static noinline __init void find_memory_chunks(unsigned long memsize)
	193	{
	194	unsigned long addr = 0, old_addr = 0;
	195	unsigned long old_cc = CHUNK_READ_WRITE;
	196	unsigned long cc;
	197	int chunk = 0;
	198
	199	while (chunk < MEMORY_CHUNKS) {
	200	cc = __tprot(addr);
	201	while (cc == old_cc) {
	202	addr += CHUNK_INCR;
a2cb0737	203	if (memsize && addr >= memsize)
0b8da654	204	break;
ab14de6c HC	205	#ifndef CONFIG_64BIT
	206	if (addr == ADDR2G)
	207	break;
	208	#endif
0b8da654	209	cc = __tprot(addr);
ab14de6c HC	210	}
	211
	212	if (old_addr != addr &&
	213	(old_cc == CHUNK_READ_WRITE \|\| old_cc == CHUNK_READ_ONLY)) {
	214	memory_chunk[chunk].addr = old_addr;
	215	memory_chunk[chunk].size = addr - old_addr;
	216	memory_chunk[chunk].type = old_cc;
	217	chunk++;
	218	}
	219
	220	old_addr = addr;
	221	old_cc = cc;
	222
	223	#ifndef CONFIG_64BIT
	224	if (addr == ADDR2G)
	225	break;
	226	#endif
	227	/*
29c380f5 HC	228	* Finish memory detection at the first hole
29c380f5 HC	229	* if storage size is unknown.
ab14de6c	230	*/
29c380f5	231	if (cc == -1UL && !memsize)
ab14de6c HC	232	break;
	233	if (memsize && addr >= memsize)
	234	break;
	235	}
	236	}
	237
	238	static __init void early_pgm_check_handler(void)
	239	{
	240	unsigned long addr;
	241	const struct exception_table_entry *fixup;
	242
	243	addr = S390_lowcore.program_old_psw.addr;
	244	fixup = search_exception_tables(addr & PSW_ADDR_INSN);
	245	if (!fixup)
	246	disabled_wait(0);
	247	S390_lowcore.program_old_psw.addr = fixup->fixup \| PSW_ADDR_AMODE;
	248	}
	249
	250	static noinline __init void setup_lowcore_early(void)
	251	{
	252	psw_t psw;
	253
	254	psw.mask = PSW_BASE_BITS \| PSW_DEFAULT_KEY;
	255	psw.addr = PSW_ADDR_AMODE \| (unsigned long) s390_base_ext_handler;
	256	S390_lowcore.external_new_psw = psw;
	257	psw.addr = PSW_ADDR_AMODE \| (unsigned long) s390_base_pgm_handler;
	258	S390_lowcore.program_new_psw = psw;
	259	s390_base_pgm_handler_fn = early_pgm_check_handler;
	260	}
	261
	262	/*
	263	* Save ipl parameters, clear bss memory, initialize storage keys
	264	* and create a kernel NSS at startup if the SAVESYS= parm is defined
	265	*/
	266	void __init startup_init(void)
	267	{
05dd2530	268	unsigned long long memsize;
ab14de6c HC	269
	270	ipl_save_parameters();
	271	clear_bss_section();
	272	init_kernel_storage_key();
	273	lockdep_init();
	274	lockdep_off();
	275	detect_machine_type();
	276	create_kernel_nss();
	277	sort_main_extable();
	278	setup_lowcore_early();
08d07968	279	sclp_read_info_early();
83119ad4	280	sclp_facilities_detect();
ab14de6c	281	memsize = sclp_memory_detect();
05dd2530 HC	282	#ifndef CONFIG_64BIT
	283	/*
	284	* Can't deal with more than 2G in 31 bit addressing mode, so
	285	* limit the value in order to avoid strange side effects.
	286	*/
	287	if (memsize > ADDR2G)
	288	memsize = ADDR2G;
	289	#endif
ab14de6c	290	if (memory_fast_detect() < 0)
05dd2530	291	find_memory_chunks((unsigned long) memsize);
ab14de6c HC	292	lockdep_on();
ab14de6c HC	293	}