Merge branch 'linus' into sched/core
[linux-3.10.git] / arch / s390 / kernel / early.c
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 "entry.h"
33
34 /*
35  * Create a Kernel NSS if the SAVESYS= parameter is defined
36  */
37 #define DEFSYS_CMD_SIZE         128
38 #define SAVESYS_CMD_SIZE        32
39
40 char kernel_nss_name[NSS_NAME_SIZE + 1];
41
42 static void __init setup_boot_command_line(void);
43
44 /*
45  * Get the TOD clock running.
46  */
47 static void __init reset_tod_clock(void)
48 {
49         u64 time;
50
51         if (store_clock(&time) == 0)
52                 return;
53         /* TOD clock not running. Set the clock to Unix Epoch. */
54         if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0)
55                 disabled_wait(0);
56
57         sched_clock_base_cc = TOD_UNIX_EPOCH;
58         S390_lowcore.last_update_clock = sched_clock_base_cc;
59 }
60
61 #ifdef CONFIG_SHARED_KERNEL
62 int __init savesys_ipl_nss(char *cmd, const int cmdlen);
63
64 asm(
65         "       .section .init.text,\"ax\",@progbits\n"
66         "       .align  4\n"
67         "       .type   savesys_ipl_nss, @function\n"
68         "savesys_ipl_nss:\n"
69 #ifdef CONFIG_64BIT
70         "       stmg    6,15,48(15)\n"
71         "       lgr     14,3\n"
72         "       sam31\n"
73         "       diag    2,14,0x8\n"
74         "       sam64\n"
75         "       lgr     2,14\n"
76         "       lmg     6,15,48(15)\n"
77 #else
78         "       stm     6,15,24(15)\n"
79         "       lr      14,3\n"
80         "       diag    2,14,0x8\n"
81         "       lr      2,14\n"
82         "       lm      6,15,24(15)\n"
83 #endif
84         "       br      14\n"
85         "       .size   savesys_ipl_nss, .-savesys_ipl_nss\n"
86         "       .previous\n");
87
88 static __initdata char upper_command_line[COMMAND_LINE_SIZE];
89
90 static noinline __init void create_kernel_nss(void)
91 {
92         unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
93 #ifdef CONFIG_BLK_DEV_INITRD
94         unsigned int sinitrd_pfn, einitrd_pfn;
95 #endif
96         int response;
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         sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
128                 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
129                 eshared_pfn, end_pfn);
130
131 #ifdef CONFIG_BLK_DEV_INITRD
132         if (INITRD_START && INITRD_SIZE) {
133                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
134                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
135                 min_size = einitrd_pfn << 2;
136                 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
137                 sinitrd_pfn, einitrd_pfn);
138         }
139 #endif
140
141         sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13",
142                 defsys_cmd, min_size);
143         sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
144                 kernel_nss_name, kernel_nss_name);
145
146         __cpcmd(defsys_cmd, NULL, 0, &response);
147
148         if (response != 0) {
149                 pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
150                         response);
151                 kernel_nss_name[0] = '\0';
152                 return;
153         }
154
155         len = strlen(savesys_cmd);
156         ASCEBC(savesys_cmd, len);
157         response = savesys_ipl_nss(savesys_cmd, len);
158
159         /* On success: response is equal to the command size,
160          *             max SAVESYS_CMD_SIZE
161          * On error: response contains the numeric portion of cp error message.
162          *           for SAVESYS it will be >= 263
163          *           for missing privilege class, it will be 1
164          */
165         if (response > SAVESYS_CMD_SIZE || response == 1) {
166                 pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
167                         response);
168                 kernel_nss_name[0] = '\0';
169                 return;
170         }
171
172         /* re-initialize cputime accounting. */
173         sched_clock_base_cc = get_clock();
174         S390_lowcore.last_update_clock = sched_clock_base_cc;
175         S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
176         S390_lowcore.user_timer = 0;
177         S390_lowcore.system_timer = 0;
178         asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
179
180         /* re-setup boot command line with new ipl vm parms */
181         ipl_update_parameters();
182         setup_boot_command_line();
183
184         ipl_flags = IPL_NSS_VALID;
185 }
186
187 #else /* CONFIG_SHARED_KERNEL */
188
189 static inline void create_kernel_nss(void) { }
190
191 #endif /* CONFIG_SHARED_KERNEL */
192
193 /*
194  * Clear bss memory
195  */
196 static noinline __init void clear_bss_section(void)
197 {
198         memset(__bss_start, 0, __bss_stop - __bss_start);
199 }
200
201 /*
202  * Initialize storage key for kernel pages
203  */
204 static noinline __init void init_kernel_storage_key(void)
205 {
206         unsigned long end_pfn, init_pfn;
207
208         end_pfn = PFN_UP(__pa(&_end));
209
210         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
211                 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
212 }
213
214 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
215
216 static noinline __init void detect_machine_type(void)
217 {
218         /* Check current-configuration-level */
219         if ((stsi(NULL, 0, 0, 0) >> 28) <= 2) {
220                 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
221                 return;
222         }
223         /* Get virtual-machine cpu information. */
224         if (stsi(&vmms, 3, 2, 2) == -ENOSYS || !vmms.count)
225                 return;
226
227         /* Running under KVM? If not we assume z/VM */
228         if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
229                 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
230         else
231                 S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
232 }
233
234 static __init void early_pgm_check_handler(void)
235 {
236         unsigned long addr;
237         const struct exception_table_entry *fixup;
238
239         addr = S390_lowcore.program_old_psw.addr;
240         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
241         if (!fixup)
242                 disabled_wait(0);
243         S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
244 }
245
246 static noinline __init void setup_lowcore_early(void)
247 {
248         psw_t psw;
249
250         psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
251         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
252         S390_lowcore.external_new_psw = psw;
253         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
254         S390_lowcore.program_new_psw = psw;
255         s390_base_pgm_handler_fn = early_pgm_check_handler;
256 }
257
258 static noinline __init void setup_hpage(void)
259 {
260 #ifndef CONFIG_DEBUG_PAGEALLOC
261         unsigned int facilities;
262
263         facilities = stfl();
264         if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
265                 return;
266         S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
267         __ctl_set_bit(0, 23);
268 #endif
269 }
270
271 static __init void detect_mvpg(void)
272 {
273 #ifndef CONFIG_64BIT
274         int rc;
275
276         asm volatile(
277                 "       la      0,0\n"
278                 "       mvpg    %2,%2\n"
279                 "0:     la      %0,0\n"
280                 "1:\n"
281                 EX_TABLE(0b,1b)
282                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
283         if (!rc)
284                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
285 #endif
286 }
287
288 static __init void detect_ieee(void)
289 {
290 #ifndef CONFIG_64BIT
291         int rc, tmp;
292
293         asm volatile(
294                 "       efpc    %1,0\n"
295                 "0:     la      %0,0\n"
296                 "1:\n"
297                 EX_TABLE(0b,1b)
298                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
299         if (!rc)
300                 S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
301 #endif
302 }
303
304 static __init void detect_csp(void)
305 {
306 #ifndef CONFIG_64BIT
307         int rc;
308
309         asm volatile(
310                 "       la      0,0\n"
311                 "       la      1,0\n"
312                 "       la      2,4\n"
313                 "       csp     0,2\n"
314                 "0:     la      %0,0\n"
315                 "1:\n"
316                 EX_TABLE(0b,1b)
317                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
318         if (!rc)
319                 S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
320 #endif
321 }
322
323 static __init void detect_diag9c(void)
324 {
325         unsigned int cpu_address;
326         int rc;
327
328         cpu_address = stap();
329         asm volatile(
330                 "       diag    %2,0,0x9c\n"
331                 "0:     la      %0,0\n"
332                 "1:\n"
333                 EX_TABLE(0b,1b)
334                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
335         if (!rc)
336                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
337 }
338
339 static __init void detect_diag44(void)
340 {
341 #ifdef CONFIG_64BIT
342         int rc;
343
344         asm volatile(
345                 "       diag    0,0,0x44\n"
346                 "0:     la      %0,0\n"
347                 "1:\n"
348                 EX_TABLE(0b,1b)
349                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
350         if (!rc)
351                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
352 #endif
353 }
354
355 static __init void detect_machine_facilities(void)
356 {
357 #ifdef CONFIG_64BIT
358         unsigned int facilities;
359
360         facilities = stfl();
361         if (facilities & (1 << 28))
362                 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
363         if (facilities & (1 << 23))
364                 S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
365         if (facilities & (1 << 4))
366                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
367 #endif
368 }
369
370 static __init void rescue_initrd(void)
371 {
372 #ifdef CONFIG_BLK_DEV_INITRD
373         /*
374          * Move the initrd right behind the bss section in case it starts
375          * within the bss section. So we don't overwrite it when the bss
376          * section gets cleared.
377          */
378         if (!INITRD_START || !INITRD_SIZE)
379                 return;
380         if (INITRD_START >= (unsigned long) __bss_stop)
381                 return;
382         memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE);
383         INITRD_START = (unsigned long) __bss_stop;
384 #endif
385 }
386
387 /* Set up boot command line */
388 static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
389 {
390         char *parm, *delim;
391         size_t rc, len;
392
393         len = strlen(boot_command_line);
394
395         delim = boot_command_line + len;        /* '\0' character position */
396         parm  = boot_command_line + len + 1;    /* append right after '\0' */
397
398         rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
399         if (rc) {
400                 if (*parm == '=')
401                         memmove(boot_command_line, parm + 1, rc);
402                 else
403                         *delim = ' ';           /* replace '\0' with space */
404         }
405 }
406
407 static void __init setup_boot_command_line(void)
408 {
409         int i;
410
411         /* convert arch command line to ascii */
412         for (i = 0; i < ARCH_COMMAND_LINE_SIZE; i++)
413                 if (COMMAND_LINE[i] & 0x80)
414                         break;
415         if (i < ARCH_COMMAND_LINE_SIZE)
416                 EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
417         COMMAND_LINE[ARCH_COMMAND_LINE_SIZE-1] = 0;
418
419         /* copy arch command line */
420         strlcpy(boot_command_line, strstrip(COMMAND_LINE),
421                 ARCH_COMMAND_LINE_SIZE);
422
423         /* append IPL PARM data to the boot command line */
424         if (MACHINE_IS_VM)
425                 append_to_cmdline(append_ipl_vmparm);
426
427         append_to_cmdline(append_ipl_scpdata);
428 }
429
430
431 /*
432  * Save ipl parameters, clear bss memory, initialize storage keys
433  * and create a kernel NSS at startup if the SAVESYS= parm is defined
434  */
435 void __init startup_init(void)
436 {
437         reset_tod_clock();
438         ipl_save_parameters();
439         rescue_initrd();
440         clear_bss_section();
441         init_kernel_storage_key();
442         lockdep_init();
443         lockdep_off();
444         sort_main_extable();
445         setup_lowcore_early();
446         detect_machine_type();
447         ipl_update_parameters();
448         setup_boot_command_line();
449         create_kernel_nss();
450         detect_mvpg();
451         detect_ieee();
452         detect_csp();
453         detect_diag9c();
454         detect_diag44();
455         detect_machine_facilities();
456         setup_hpage();
457         sclp_facilities_detect();
458         detect_memory_layout(memory_chunk);
459 #ifdef CONFIG_DYNAMIC_FTRACE
460         S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
461 #endif
462         lockdep_on();
463 }