1 /*
2 * arch/s390/kernel/early.c
3 *
4 * Copyright IBM Corp. 2007, 2009
5 * Author(s): Hongjie Yang <hongjie@us.ibm.com>,
6 * Heiko Carstens <heiko.carstens@de.ibm.com>
7 */
8
9 #define KMSG_COMPONENT "setup"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12 #include <linux/compiler.h>
13 #include <linux/init.h>
14 #include <linux/errno.h>
15 #include <linux/string.h>
16 #include <linux/ctype.h>
17 #include <linux/ftrace.h>
18 #include <linux/lockdep.h>
19 #include <linux/module.h>
20 #include <linux/pfn.h>
21 #include <linux/uaccess.h>
22 #include <linux/kernel.h>
23 #include <asm/ebcdic.h>
24 #include <asm/ipl.h>
25 #include <asm/lowcore.h>
26 #include <asm/processor.h>
27 #include <asm/sections.h>
28 #include <asm/setup.h>
29 #include <asm/sysinfo.h>
30 #include <asm/cpcmd.h>
31 #include <asm/sclp.h>
32 #include <asm/facility.h>
33 #include "entry.h"
34
35 /*
36 * Create a Kernel NSS if the SAVESYS= parameter is defined
37 */
38 #define DEFSYS_CMD_SIZE 128
39 #define SAVESYS_CMD_SIZE 32
40
41 char kernel_nss_name[NSS_NAME_SIZE + 1];
42
43 static void __init setup_boot_command_line(void);
44
45 /*
46 * Get the TOD clock running.
47 */
reset_tod_clock(void)48 static void __init reset_tod_clock(void)
49 {
50 u64 time;
51
52 if (store_clock(&time) == 0)
53 return;
54 /* TOD clock not running. Set the clock to Unix Epoch. */
55 if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0)
56 disabled_wait(0);
57
58 sched_clock_base_cc = TOD_UNIX_EPOCH;
59 S390_lowcore.last_update_clock = sched_clock_base_cc;
60 }
61
62 #ifdef CONFIG_SHARED_KERNEL
63 int __init savesys_ipl_nss(char *cmd, const int cmdlen);
64
65 asm(
66 " .section .init.text,\"ax\",@progbits\n"
67 " .align 4\n"
68 " .type savesys_ipl_nss, @function\n"
69 "savesys_ipl_nss:\n"
70 #ifdef CONFIG_64BIT
71 " stmg 6,15,48(15)\n"
72 " lgr 14,3\n"
73 " sam31\n"
74 " diag 2,14,0x8\n"
75 " sam64\n"
76 " lgr 2,14\n"
77 " lmg 6,15,48(15)\n"
78 #else
79 " stm 6,15,24(15)\n"
80 " lr 14,3\n"
81 " diag 2,14,0x8\n"
82 " lr 2,14\n"
83 " lm 6,15,24(15)\n"
84 #endif
85 " br 14\n"
86 " .size savesys_ipl_nss, .-savesys_ipl_nss\n"
87 " .previous\n");
88
89 static __initdata char upper_command_line[COMMAND_LINE_SIZE];
90
create_kernel_nss(void)91 static noinline __init void create_kernel_nss(void)
92 {
93 unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
94 #ifdef CONFIG_BLK_DEV_INITRD
95 unsigned int sinitrd_pfn, einitrd_pfn;
96 #endif
97 int response;
98 int hlen;
99 size_t len;
100 char *savesys_ptr;
101 char defsys_cmd[DEFSYS_CMD_SIZE];
102 char savesys_cmd[SAVESYS_CMD_SIZE];
103
104 /* Do nothing if we are not running under VM */
105 if (!MACHINE_IS_VM)
106 return;
107
108 /* Convert COMMAND_LINE to upper case */
109 for (i = 0; i < strlen(boot_command_line); i++)
110 upper_command_line[i] = toupper(boot_command_line[i]);
111
112 savesys_ptr = strstr(upper_command_line, "SAVESYS=");
113
114 if (!savesys_ptr)
115 return;
116
117 savesys_ptr += 8; /* Point to the beginning of the NSS name */
118 for (i = 0; i < NSS_NAME_SIZE; i++) {
119 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
120 break;
121 kernel_nss_name[i] = savesys_ptr[i];
122 }
123
124 stext_pfn = PFN_DOWN(__pa(&_stext));
125 eshared_pfn = PFN_DOWN(__pa(&_eshared));
126 end_pfn = PFN_UP(__pa(&_end));
127 min_size = end_pfn << 2;
128
129 hlen = snprintf(defsys_cmd, DEFSYS_CMD_SIZE,
130 "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
131 kernel_nss_name, stext_pfn - 1, stext_pfn,
132 eshared_pfn - 1, eshared_pfn, end_pfn);
133
134 #ifdef CONFIG_BLK_DEV_INITRD
135 if (INITRD_START && INITRD_SIZE) {
136 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
137 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
138 min_size = einitrd_pfn << 2;
139 hlen += snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
140 " EW %.5X-%.5X", sinitrd_pfn, einitrd_pfn);
141 }
142 #endif
143
144 snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
145 " EW MINSIZE=%.7iK PARMREGS=0-13", min_size);
146 defsys_cmd[DEFSYS_CMD_SIZE - 1] = '\0';
147 snprintf(savesys_cmd, SAVESYS_CMD_SIZE, "SAVESYS %s \n IPL %s",
148 kernel_nss_name, kernel_nss_name);
149 savesys_cmd[SAVESYS_CMD_SIZE - 1] = '\0';
150
151 __cpcmd(defsys_cmd, NULL, 0, &response);
152
153 if (response != 0) {
154 pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
155 response);
156 kernel_nss_name[0] = '\0';
157 return;
158 }
159
160 len = strlen(savesys_cmd);
161 ASCEBC(savesys_cmd, len);
162 response = savesys_ipl_nss(savesys_cmd, len);
163
164 /* On success: response is equal to the command size,
165 * max SAVESYS_CMD_SIZE
166 * On error: response contains the numeric portion of cp error message.
167 * for SAVESYS it will be >= 263
168 * for missing privilege class, it will be 1
169 */
170 if (response > SAVESYS_CMD_SIZE || response == 1) {
171 pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
172 response);
173 kernel_nss_name[0] = '\0';
174 return;
175 }
176
177 /* re-initialize cputime accounting. */
178 sched_clock_base_cc = get_clock();
179 S390_lowcore.last_update_clock = sched_clock_base_cc;
180 S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
181 S390_lowcore.user_timer = 0;
182 S390_lowcore.system_timer = 0;
183 asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
184
185 /* re-setup boot command line with new ipl vm parms */
186 ipl_update_parameters();
187 setup_boot_command_line();
188
189 ipl_flags = IPL_NSS_VALID;
190 }
191
192 #else /* CONFIG_SHARED_KERNEL */
193
create_kernel_nss(void)194 static inline void create_kernel_nss(void) { }
195
196 #endif /* CONFIG_SHARED_KERNEL */
197
198 /*
199 * Clear bss memory
200 */
clear_bss_section(void)201 static noinline __init void clear_bss_section(void)
202 {
203 memset(__bss_start, 0, __bss_stop - __bss_start);
204 }
205
206 /*
207 * Initialize storage key for kernel pages
208 */
init_kernel_storage_key(void)209 static noinline __init void init_kernel_storage_key(void)
210 {
211 unsigned long end_pfn, init_pfn;
212
213 end_pfn = PFN_UP(__pa(&_end));
214
215 for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
216 page_set_storage_key(init_pfn << PAGE_SHIFT,
217 PAGE_DEFAULT_KEY, 0);
218 }
219
220 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
221
detect_machine_type(void)222 static noinline __init void detect_machine_type(void)
223 {
224 /* Check current-configuration-level */
225 if ((stsi(NULL, 0, 0, 0) >> 28) <= 2) {
226 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
227 return;
228 }
229 /* Get virtual-machine cpu information. */
230 if (stsi(&vmms, 3, 2, 2) == -ENOSYS || !vmms.count)
231 return;
232
233 /* Running under KVM? If not we assume z/VM */
234 if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
235 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
236 else
237 S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
238 }
239
early_pgm_check_handler(void)240 static __init void early_pgm_check_handler(void)
241 {
242 unsigned long addr;
243 const struct exception_table_entry *fixup;
244
245 addr = S390_lowcore.program_old_psw.addr;
246 fixup = search_exception_tables(addr & PSW_ADDR_INSN);
247 if (!fixup)
248 disabled_wait(0);
249 S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
250 }
251
setup_lowcore_early(void)252 static noinline __init void setup_lowcore_early(void)
253 {
254 psw_t psw;
255
256 psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA;
257 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
258 S390_lowcore.external_new_psw = psw;
259 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
260 S390_lowcore.program_new_psw = psw;
261 s390_base_pgm_handler_fn = early_pgm_check_handler;
262 }
263
setup_facility_list(void)264 static noinline __init void setup_facility_list(void)
265 {
266 stfle(S390_lowcore.stfle_fac_list,
267 ARRAY_SIZE(S390_lowcore.stfle_fac_list));
268 }
269
setup_hpage(void)270 static noinline __init void setup_hpage(void)
271 {
272 #ifndef CONFIG_DEBUG_PAGEALLOC
273 if (!test_facility(2) || !test_facility(8))
274 return;
275 S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
276 __ctl_set_bit(0, 23);
277 #endif
278 }
279
detect_mvpg(void)280 static __init void detect_mvpg(void)
281 {
282 #ifndef CONFIG_64BIT
283 int rc;
284
285 asm volatile(
286 " la 0,0\n"
287 " mvpg %2,%2\n"
288 "0: la %0,0\n"
289 "1:\n"
290 EX_TABLE(0b,1b)
291 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
292 if (!rc)
293 S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
294 #endif
295 }
296
detect_ieee(void)297 static __init void detect_ieee(void)
298 {
299 #ifndef CONFIG_64BIT
300 int rc, tmp;
301
302 asm volatile(
303 " efpc %1,0\n"
304 "0: la %0,0\n"
305 "1:\n"
306 EX_TABLE(0b,1b)
307 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
308 if (!rc)
309 S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
310 #endif
311 }
312
detect_csp(void)313 static __init void detect_csp(void)
314 {
315 #ifndef CONFIG_64BIT
316 int rc;
317
318 asm volatile(
319 " la 0,0\n"
320 " la 1,0\n"
321 " la 2,4\n"
322 " csp 0,2\n"
323 "0: la %0,0\n"
324 "1:\n"
325 EX_TABLE(0b,1b)
326 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
327 if (!rc)
328 S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
329 #endif
330 }
331
detect_diag9c(void)332 static __init void detect_diag9c(void)
333 {
334 unsigned int cpu_address;
335 int rc;
336
337 cpu_address = stap();
338 asm volatile(
339 " diag %2,0,0x9c\n"
340 "0: la %0,0\n"
341 "1:\n"
342 EX_TABLE(0b,1b)
343 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
344 if (!rc)
345 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
346 }
347
detect_diag44(void)348 static __init void detect_diag44(void)
349 {
350 #ifdef CONFIG_64BIT
351 int rc;
352
353 asm volatile(
354 " diag 0,0,0x44\n"
355 "0: la %0,0\n"
356 "1:\n"
357 EX_TABLE(0b,1b)
358 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
359 if (!rc)
360 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
361 #endif
362 }
363
detect_machine_facilities(void)364 static __init void detect_machine_facilities(void)
365 {
366 #ifdef CONFIG_64BIT
367 if (test_facility(3))
368 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
369 if (test_facility(8))
370 S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
371 if (test_facility(11))
372 S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
373 if (test_facility(27))
374 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
375 if (test_facility(40))
376 S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
377 if (test_facility(25))
378 S390_lowcore.machine_flags |= MACHINE_FLAG_STCKF;
379 #endif
380 }
381
rescue_initrd(void)382 static __init void rescue_initrd(void)
383 {
384 #ifdef CONFIG_BLK_DEV_INITRD
385 unsigned long min_initrd_addr = (unsigned long) _end + (4UL << 20);
386 /*
387 * Just like in case of IPL from VM reader we make sure there is a
388 * gap of 4MB between end of kernel and start of initrd.
389 * That way we can also be sure that saving an NSS will succeed,
390 * which however only requires different segments.
391 */
392 if (!INITRD_START || !INITRD_SIZE)
393 return;
394 if (INITRD_START >= min_initrd_addr)
395 return;
396 memmove((void *) min_initrd_addr, (void *) INITRD_START, INITRD_SIZE);
397 INITRD_START = min_initrd_addr;
398 #endif
399 }
400
401 /* Set up boot command line */
append_to_cmdline(size_t (* ipl_data)(char *,size_t))402 static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
403 {
404 char *parm, *delim;
405 size_t rc, len;
406
407 len = strlen(boot_command_line);
408
409 delim = boot_command_line + len; /* '\0' character position */
410 parm = boot_command_line + len + 1; /* append right after '\0' */
411
412 rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
413 if (rc) {
414 if (*parm == '=')
415 memmove(boot_command_line, parm + 1, rc);
416 else
417 *delim = ' '; /* replace '\0' with space */
418 }
419 }
420
has_ebcdic_char(const char * str)421 static inline int has_ebcdic_char(const char *str)
422 {
423 int i;
424
425 for (i = 0; str[i]; i++)
426 if (str[i] & 0x80)
427 return 1;
428 return 0;
429 }
430
setup_boot_command_line(void)431 static void __init setup_boot_command_line(void)
432 {
433 COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
434 /* convert arch command line to ascii if necessary */
435 if (has_ebcdic_char(COMMAND_LINE))
436 EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
437 /* copy arch command line */
438 strlcpy(boot_command_line, strstrip(COMMAND_LINE),
439 ARCH_COMMAND_LINE_SIZE);
440
441 /* append IPL PARM data to the boot command line */
442 if (MACHINE_IS_VM)
443 append_to_cmdline(append_ipl_vmparm);
444
445 append_to_cmdline(append_ipl_scpdata);
446 }
447
448
449 /*
450 * Save ipl parameters, clear bss memory, initialize storage keys
451 * and create a kernel NSS at startup if the SAVESYS= parm is defined
452 */
startup_init(void)453 void __init startup_init(void)
454 {
455 reset_tod_clock();
456 ipl_save_parameters();
457 rescue_initrd();
458 clear_bss_section();
459 init_kernel_storage_key();
460 lockdep_init();
461 lockdep_off();
462 sort_main_extable();
463 setup_lowcore_early();
464 setup_facility_list();
465 detect_machine_type();
466 ipl_update_parameters();
467 setup_boot_command_line();
468 create_kernel_nss();
469 detect_mvpg();
470 detect_ieee();
471 detect_csp();
472 detect_diag9c();
473 detect_diag44();
474 detect_machine_facilities();
475 setup_hpage();
476 sclp_facilities_detect();
477 detect_memory_layout(memory_chunk);
478 #ifdef CONFIG_DYNAMIC_FTRACE
479 S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
480 #endif
481 lockdep_on();
482 }
483