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