1/*
2 *    Copyright IBM Corp. 2007, 2009
3 *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
4 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
5 */
6
7#define KMSG_COMPONENT "setup"
8#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9
10#include <linux/compiler.h>
11#include <linux/init.h>
12#include <linux/errno.h>
13#include <linux/string.h>
14#include <linux/ctype.h>
15#include <linux/ftrace.h>
16#include <linux/lockdep.h>
17#include <linux/module.h>
18#include <linux/pfn.h>
19#include <linux/uaccess.h>
20#include <linux/kernel.h>
21#include <asm/ebcdic.h>
22#include <asm/ipl.h>
23#include <asm/lowcore.h>
24#include <asm/processor.h>
25#include <asm/sections.h>
26#include <asm/setup.h>
27#include <asm/sysinfo.h>
28#include <asm/cpcmd.h>
29#include <asm/sclp.h>
30#include <asm/facility.h>
31#include "entry.h"
32
33/*
34 * Create a Kernel NSS if the SAVESYS= parameter is defined
35 */
36#define DEFSYS_CMD_SIZE		128
37#define SAVESYS_CMD_SIZE	32
38
39char kernel_nss_name[NSS_NAME_SIZE + 1];
40
41static void __init setup_boot_command_line(void);
42
43/*
44 * Get the TOD clock running.
45 */
46static void __init reset_tod_clock(void)
47{
48	u64 time;
49
50	if (store_tod_clock(&time) == 0)
51		return;
52	/* TOD clock not running. Set the clock to Unix Epoch. */
53	if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0)
54		disabled_wait(0);
55
56	sched_clock_base_cc = TOD_UNIX_EPOCH;
57	S390_lowcore.last_update_clock = sched_clock_base_cc;
58}
59
60#ifdef CONFIG_SHARED_KERNEL
61int __init savesys_ipl_nss(char *cmd, const int cmdlen);
62
63asm(
64	"	.section .init.text,\"ax\",@progbits\n"
65	"	.align	4\n"
66	"	.type	savesys_ipl_nss, @function\n"
67	"savesys_ipl_nss:\n"
68#ifdef CONFIG_64BIT
69	"	stmg	6,15,48(15)\n"
70	"	lgr	14,3\n"
71	"	sam31\n"
72	"	diag	2,14,0x8\n"
73	"	sam64\n"
74	"	lgr	2,14\n"
75	"	lmg	6,15,48(15)\n"
76#else
77	"	stm	6,15,24(15)\n"
78	"	lr	14,3\n"
79	"	diag	2,14,0x8\n"
80	"	lr	2,14\n"
81	"	lm	6,15,24(15)\n"
82#endif
83	"	br	14\n"
84	"	.size	savesys_ipl_nss, .-savesys_ipl_nss\n"
85	"	.previous\n");
86
87static __initdata char upper_command_line[COMMAND_LINE_SIZE];
88
89static noinline __init void create_kernel_nss(void)
90{
91	unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
92#ifdef CONFIG_BLK_DEV_INITRD
93	unsigned int sinitrd_pfn, einitrd_pfn;
94#endif
95	int response;
96	int hlen;
97	size_t len;
98	char *savesys_ptr;
99	char defsys_cmd[DEFSYS_CMD_SIZE];
100	char savesys_cmd[SAVESYS_CMD_SIZE];
101
102	/* Do nothing if we are not running under VM */
103	if (!MACHINE_IS_VM)
104		return;
105
106	/* Convert COMMAND_LINE to upper case */
107	for (i = 0; i < strlen(boot_command_line); i++)
108		upper_command_line[i] = toupper(boot_command_line[i]);
109
110	savesys_ptr = strstr(upper_command_line, "SAVESYS=");
111
112	if (!savesys_ptr)
113		return;
114
115	savesys_ptr += 8;    /* Point to the beginning of the NSS name */
116	for (i = 0; i < NSS_NAME_SIZE; i++) {
117		if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
118			break;
119		kernel_nss_name[i] = savesys_ptr[i];
120	}
121
122	stext_pfn = PFN_DOWN(__pa(&_stext));
123	eshared_pfn = PFN_DOWN(__pa(&_eshared));
124	end_pfn = PFN_UP(__pa(&_end));
125	min_size = end_pfn << 2;
126
127	hlen = snprintf(defsys_cmd, DEFSYS_CMD_SIZE,
128			"DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
129			kernel_nss_name, stext_pfn - 1, stext_pfn,
130			eshared_pfn - 1, eshared_pfn, end_pfn);
131
132#ifdef CONFIG_BLK_DEV_INITRD
133	if (INITRD_START && INITRD_SIZE) {
134		sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
135		einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
136		min_size = einitrd_pfn << 2;
137		hlen += snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
138				 " EW %.5X-%.5X", sinitrd_pfn, einitrd_pfn);
139	}
140#endif
141
142	snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
143		 " EW MINSIZE=%.7iK PARMREGS=0-13", min_size);
144	defsys_cmd[DEFSYS_CMD_SIZE - 1] = '\0';
145	snprintf(savesys_cmd, SAVESYS_CMD_SIZE, "SAVESYS %s \n IPL %s",
146		 kernel_nss_name, kernel_nss_name);
147	savesys_cmd[SAVESYS_CMD_SIZE - 1] = '\0';
148
149	__cpcmd(defsys_cmd, NULL, 0, &response);
150
151	if (response != 0) {
152		pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
153			response);
154		kernel_nss_name[0] = '\0';
155		return;
156	}
157
158	len = strlen(savesys_cmd);
159	ASCEBC(savesys_cmd, len);
160	response = savesys_ipl_nss(savesys_cmd, len);
161
162	/* On success: response is equal to the command size,
163	 *	       max SAVESYS_CMD_SIZE
164	 * On error: response contains the numeric portion of cp error message.
165	 *	     for SAVESYS it will be >= 263
166	 *	     for missing privilege class, it will be 1
167	 */
168	if (response > SAVESYS_CMD_SIZE || response == 1) {
169		pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
170			response);
171		kernel_nss_name[0] = '\0';
172		return;
173	}
174
175	/* re-initialize cputime accounting. */
176	sched_clock_base_cc = get_tod_clock();
177	S390_lowcore.last_update_clock = sched_clock_base_cc;
178	S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
179	S390_lowcore.user_timer = 0;
180	S390_lowcore.system_timer = 0;
181	asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
182
183	/* re-setup boot command line with new ipl vm parms */
184	ipl_update_parameters();
185	setup_boot_command_line();
186
187	ipl_flags = IPL_NSS_VALID;
188}
189
190#else /* CONFIG_SHARED_KERNEL */
191
192static inline void create_kernel_nss(void) { }
193
194#endif /* CONFIG_SHARED_KERNEL */
195
196/*
197 * Clear bss memory
198 */
199static noinline __init void clear_bss_section(void)
200{
201	memset(__bss_start, 0, __bss_stop - __bss_start);
202}
203
204/*
205 * Initialize storage key for kernel pages
206 */
207static noinline __init void init_kernel_storage_key(void)
208{
209#if PAGE_DEFAULT_KEY
210	unsigned long end_pfn, init_pfn;
211
212	end_pfn = PFN_UP(__pa(&_end));
213
214	for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
215		page_set_storage_key(init_pfn << PAGE_SHIFT,
216				     PAGE_DEFAULT_KEY, 0);
217#endif
218}
219
220static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE);
221
222static noinline __init void detect_machine_type(void)
223{
224	struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;
225
226	/* Check current-configuration-level */
227	if (stsi(NULL, 0, 0, 0) <= 2) {
228		S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
229		return;
230	}
231	/* Get virtual-machine cpu information. */
232	if (stsi(vmms, 3, 2, 2) || !vmms->count)
233		return;
234
235	/* Running under KVM? If not we assume z/VM */
236	if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
237		S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
238	else
239		S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
240}
241
242static __init void setup_topology(void)
243{
244#ifdef CONFIG_64BIT
245	int max_mnest;
246
247	if (!test_facility(11))
248		return;
249	S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
250	for (max_mnest = 6; max_mnest > 1; max_mnest--) {
251		if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
252			break;
253	}
254	topology_max_mnest = max_mnest;
255#endif
256}
257
258static void early_pgm_check_handler(void)
259{
260	const struct exception_table_entry *fixup;
261	unsigned long cr0, cr0_new;
262	unsigned long addr;
263
264	addr = S390_lowcore.program_old_psw.addr;
265	fixup = search_exception_tables(addr & PSW_ADDR_INSN);
266	if (!fixup)
267		disabled_wait(0);
268	/* Disable low address protection before storing into lowcore. */
269	__ctl_store(cr0, 0, 0);
270	cr0_new = cr0 & ~(1UL << 28);
271	__ctl_load(cr0_new, 0, 0);
272	S390_lowcore.program_old_psw.addr = extable_fixup(fixup)|PSW_ADDR_AMODE;
273	__ctl_load(cr0, 0, 0);
274}
275
276static noinline __init void setup_lowcore_early(void)
277{
278	psw_t psw;
279
280	psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA;
281	psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
282	S390_lowcore.external_new_psw = psw;
283	psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
284	S390_lowcore.program_new_psw = psw;
285	s390_base_pgm_handler_fn = early_pgm_check_handler;
286}
287
288static noinline __init void setup_facility_list(void)
289{
290	stfle(S390_lowcore.stfle_fac_list,
291	      ARRAY_SIZE(S390_lowcore.stfle_fac_list));
292}
293
294static __init void detect_mvpg(void)
295{
296#ifndef CONFIG_64BIT
297	int rc;
298
299	asm volatile(
300		"	la	0,0\n"
301		"	mvpg	%2,%2\n"
302		"0:	la	%0,0\n"
303		"1:\n"
304		EX_TABLE(0b,1b)
305		: "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
306	if (!rc)
307		S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
308#endif
309}
310
311static __init void detect_ieee(void)
312{
313#ifndef CONFIG_64BIT
314	int rc, tmp;
315
316	asm volatile(
317		"	efpc	%1,0\n"
318		"0:	la	%0,0\n"
319		"1:\n"
320		EX_TABLE(0b,1b)
321		: "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
322	if (!rc)
323		S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
324#endif
325}
326
327static __init void detect_csp(void)
328{
329#ifndef CONFIG_64BIT
330	int rc;
331
332	asm volatile(
333		"	la	0,0\n"
334		"	la	1,0\n"
335		"	la	2,4\n"
336		"	csp	0,2\n"
337		"0:	la	%0,0\n"
338		"1:\n"
339		EX_TABLE(0b,1b)
340		: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
341	if (!rc)
342		S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
343#endif
344}
345
346static __init void detect_diag9c(void)
347{
348	unsigned int cpu_address;
349	int rc;
350
351	cpu_address = stap();
352	asm volatile(
353		"	diag	%2,0,0x9c\n"
354		"0:	la	%0,0\n"
355		"1:\n"
356		EX_TABLE(0b,1b)
357		: "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
358	if (!rc)
359		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
360}
361
362static __init void detect_diag44(void)
363{
364#ifdef CONFIG_64BIT
365	int rc;
366
367	asm volatile(
368		"	diag	0,0,0x44\n"
369		"0:	la	%0,0\n"
370		"1:\n"
371		EX_TABLE(0b,1b)
372		: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
373	if (!rc)
374		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
375#endif
376}
377
378static __init void detect_machine_facilities(void)
379{
380#ifdef CONFIG_64BIT
381	if (test_facility(8)) {
382		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1;
383		__ctl_set_bit(0, 23);
384	}
385	if (test_facility(78))
386		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2;
387	if (test_facility(3))
388		S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
389	if (test_facility(40))
390		S390_lowcore.machine_flags |= MACHINE_FLAG_LPP;
391	if (test_facility(50) && test_facility(73))
392		S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
393	if (test_facility(51))
394		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
395	if (test_facility(129))
396		S390_lowcore.machine_flags |= MACHINE_FLAG_VX;
397#endif
398}
399
400static __init void rescue_initrd(void)
401{
402#ifdef CONFIG_BLK_DEV_INITRD
403	unsigned long min_initrd_addr = (unsigned long) _end + (4UL << 20);
404	/*
405	 * Just like in case of IPL from VM reader we make sure there is a
406	 * gap of 4MB between end of kernel and start of initrd.
407	 * That way we can also be sure that saving an NSS will succeed,
408	 * which however only requires different segments.
409	 */
410	if (!INITRD_START || !INITRD_SIZE)
411		return;
412	if (INITRD_START >= min_initrd_addr)
413		return;
414	memmove((void *) min_initrd_addr, (void *) INITRD_START, INITRD_SIZE);
415	INITRD_START = min_initrd_addr;
416#endif
417}
418
419/* Set up boot command line */
420static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
421{
422	char *parm, *delim;
423	size_t rc, len;
424
425	len = strlen(boot_command_line);
426
427	delim = boot_command_line + len;	/* '\0' character position */
428	parm  = boot_command_line + len + 1;	/* append right after '\0' */
429
430	rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
431	if (rc) {
432		if (*parm == '=')
433			memmove(boot_command_line, parm + 1, rc);
434		else
435			*delim = ' ';		/* replace '\0' with space */
436	}
437}
438
439static inline int has_ebcdic_char(const char *str)
440{
441	int i;
442
443	for (i = 0; str[i]; i++)
444		if (str[i] & 0x80)
445			return 1;
446	return 0;
447}
448
449static void __init setup_boot_command_line(void)
450{
451	COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
452	/* convert arch command line to ascii if necessary */
453	if (has_ebcdic_char(COMMAND_LINE))
454		EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
455	/* copy arch command line */
456	strlcpy(boot_command_line, strstrip(COMMAND_LINE),
457		ARCH_COMMAND_LINE_SIZE);
458
459	/* append IPL PARM data to the boot command line */
460	if (MACHINE_IS_VM)
461		append_to_cmdline(append_ipl_vmparm);
462
463	append_to_cmdline(append_ipl_scpdata);
464}
465
466/*
467 * Save ipl parameters, clear bss memory, initialize storage keys
468 * and create a kernel NSS at startup if the SAVESYS= parm is defined
469 */
470void __init startup_init(void)
471{
472	reset_tod_clock();
473	ipl_save_parameters();
474	rescue_initrd();
475	clear_bss_section();
476	init_kernel_storage_key();
477	lockdep_init();
478	lockdep_off();
479	setup_lowcore_early();
480	setup_facility_list();
481	detect_machine_type();
482	ipl_update_parameters();
483	setup_boot_command_line();
484	create_kernel_nss();
485	detect_mvpg();
486	detect_ieee();
487	detect_csp();
488	detect_diag9c();
489	detect_diag44();
490	detect_machine_facilities();
491	setup_topology();
492	sclp_early_detect();
493#ifdef CONFIG_DYNAMIC_FTRACE
494	S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
495#endif
496	lockdep_on();
497}
498