Merge branch 'tip/tracing/urgent-1' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6] / arch / s390 / kernel / early.c
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/compiler.h>
10 #include <linux/init.h>
11 #include <linux/errno.h>
12 #include <linux/string.h>
13 #include <linux/ctype.h>
14 #include <linux/ftrace.h>
15 #include <linux/lockdep.h>
16 #include <linux/module.h>
17 #include <linux/pfn.h>
18 #include <linux/uaccess.h>
19 #include <asm/ebcdic.h>
20 #include <asm/ipl.h>
21 #include <asm/lowcore.h>
22 #include <asm/processor.h>
23 #include <asm/sections.h>
24 #include <asm/setup.h>
25 #include <asm/sysinfo.h>
26 #include <asm/cpcmd.h>
27 #include <asm/sclp.h>
28 #include "entry.h"
29
30 /*
31  * Create a Kernel NSS if the SAVESYS= parameter is defined
32  */
33 #define DEFSYS_CMD_SIZE         128
34 #define SAVESYS_CMD_SIZE        32
35
36 char kernel_nss_name[NSS_NAME_SIZE + 1];
37
38 static unsigned long machine_flags;
39
40 static void __init setup_boot_command_line(void);
41
42 /*
43  * Get the TOD clock running.
44  */
45 static void __init reset_tod_clock(void)
46 {
47         u64 time;
48
49         if (store_clock(&time) == 0)
50                 return;
51         /* TOD clock not running. Set the clock to Unix Epoch. */
52         if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0)
53                 disabled_wait(0);
54
55         sched_clock_base_cc = TOD_UNIX_EPOCH;
56 }
57
58 #ifdef CONFIG_SHARED_KERNEL
59 int __init savesys_ipl_nss(char *cmd, const int cmdlen);
60
61 asm(
62         "       .section .init.text,\"ax\",@progbits\n"
63         "       .align  4\n"
64         "       .type   savesys_ipl_nss, @function\n"
65         "savesys_ipl_nss:\n"
66 #ifdef CONFIG_64BIT
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 #else
75         "       stm     6,15,24(15)\n"
76         "       lr      14,3\n"
77         "       diag    2,14,0x8\n"
78         "       lr      2,14\n"
79         "       lm      6,15,24(15)\n"
80 #endif
81         "       br      14\n"
82         "       .size   savesys_ipl_nss, .-savesys_ipl_nss\n");
83
84 static noinline __init void create_kernel_nss(void)
85 {
86         unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
87 #ifdef CONFIG_BLK_DEV_INITRD
88         unsigned int sinitrd_pfn, einitrd_pfn;
89 #endif
90         int response;
91         size_t len;
92         char *savesys_ptr;
93         char upper_command_line[COMMAND_LINE_SIZE];
94         char defsys_cmd[DEFSYS_CMD_SIZE];
95         char savesys_cmd[SAVESYS_CMD_SIZE];
96
97         /* Do nothing if we are not running under VM */
98         if (!MACHINE_IS_VM)
99                 return;
100
101         /* Convert COMMAND_LINE to upper case */
102         for (i = 0; i < strlen(boot_command_line); i++)
103                 upper_command_line[i] = toupper(boot_command_line[i]);
104
105         savesys_ptr = strstr(upper_command_line, "SAVESYS=");
106
107         if (!savesys_ptr)
108                 return;
109
110         savesys_ptr += 8;    /* Point to the beginning of the NSS name */
111         for (i = 0; i < NSS_NAME_SIZE; i++) {
112                 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
113                         break;
114                 kernel_nss_name[i] = savesys_ptr[i];
115         }
116
117         stext_pfn = PFN_DOWN(__pa(&_stext));
118         eshared_pfn = PFN_DOWN(__pa(&_eshared));
119         end_pfn = PFN_UP(__pa(&_end));
120         min_size = end_pfn << 2;
121
122         sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
123                 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
124                 eshared_pfn, end_pfn);
125
126 #ifdef CONFIG_BLK_DEV_INITRD
127         if (INITRD_START && INITRD_SIZE) {
128                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
129                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
130                 min_size = einitrd_pfn << 2;
131                 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
132                 sinitrd_pfn, einitrd_pfn);
133         }
134 #endif
135
136         sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13",
137                 defsys_cmd, min_size);
138         sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
139                 kernel_nss_name, kernel_nss_name);
140
141         __cpcmd(defsys_cmd, NULL, 0, &response);
142
143         if (response != 0) {
144                 kernel_nss_name[0] = '\0';
145                 return;
146         }
147
148         len = strlen(savesys_cmd);
149         ASCEBC(savesys_cmd, len);
150         response = savesys_ipl_nss(savesys_cmd, len);
151
152         /* On success: response is equal to the command size,
153          *             max SAVESYS_CMD_SIZE
154          * On error: response contains the numeric portion of cp error message.
155          *           for SAVESYS it will be >= 263
156          */
157         if (response > SAVESYS_CMD_SIZE) {
158                 kernel_nss_name[0] = '\0';
159                 return;
160         }
161
162         /* re-setup boot command line with new ipl vm parms */
163         ipl_update_parameters();
164         setup_boot_command_line();
165
166         ipl_flags = IPL_NSS_VALID;
167 }
168
169 #else /* CONFIG_SHARED_KERNEL */
170
171 static inline void create_kernel_nss(void) { }
172
173 #endif /* CONFIG_SHARED_KERNEL */
174
175 /*
176  * Clear bss memory
177  */
178 static noinline __init void clear_bss_section(void)
179 {
180         memset(__bss_start, 0, __bss_stop - __bss_start);
181 }
182
183 /*
184  * Initialize storage key for kernel pages
185  */
186 static noinline __init void init_kernel_storage_key(void)
187 {
188         unsigned long end_pfn, init_pfn;
189
190         end_pfn = PFN_UP(__pa(&_end));
191
192         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
193                 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
194 }
195
196 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
197
198 static noinline __init void detect_machine_type(void)
199 {
200         /* No VM information? Looks like LPAR */
201         if (stsi(&vmms, 3, 2, 2) == -ENOSYS)
202                 return;
203         if (!vmms.count)
204                 return;
205
206         /* Running under KVM? If not we assume z/VM */
207         if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
208                 machine_flags |= MACHINE_FLAG_KVM;
209         else
210                 machine_flags |= MACHINE_FLAG_VM;
211 }
212
213 static __init void early_pgm_check_handler(void)
214 {
215         unsigned long addr;
216         const struct exception_table_entry *fixup;
217
218         addr = S390_lowcore.program_old_psw.addr;
219         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
220         if (!fixup)
221                 disabled_wait(0);
222         S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
223 }
224
225 static noinline __init void setup_lowcore_early(void)
226 {
227         psw_t psw;
228
229         psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
230         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
231         S390_lowcore.external_new_psw = psw;
232         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
233         S390_lowcore.program_new_psw = psw;
234         s390_base_pgm_handler_fn = early_pgm_check_handler;
235 }
236
237 static noinline __init void setup_hpage(void)
238 {
239 #ifndef CONFIG_DEBUG_PAGEALLOC
240         unsigned int facilities;
241
242         facilities = stfl();
243         if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
244                 return;
245         machine_flags |= MACHINE_FLAG_HPAGE;
246         __ctl_set_bit(0, 23);
247 #endif
248 }
249
250 static __init void detect_mvpg(void)
251 {
252 #ifndef CONFIG_64BIT
253         int rc;
254
255         asm volatile(
256                 "       la      0,0\n"
257                 "       mvpg    %2,%2\n"
258                 "0:     la      %0,0\n"
259                 "1:\n"
260                 EX_TABLE(0b,1b)
261                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
262         if (!rc)
263                 machine_flags |= MACHINE_FLAG_MVPG;
264 #endif
265 }
266
267 static __init void detect_ieee(void)
268 {
269 #ifndef CONFIG_64BIT
270         int rc, tmp;
271
272         asm volatile(
273                 "       efpc    %1,0\n"
274                 "0:     la      %0,0\n"
275                 "1:\n"
276                 EX_TABLE(0b,1b)
277                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
278         if (!rc)
279                 machine_flags |= MACHINE_FLAG_IEEE;
280 #endif
281 }
282
283 static __init void detect_csp(void)
284 {
285 #ifndef CONFIG_64BIT
286         int rc;
287
288         asm volatile(
289                 "       la      0,0\n"
290                 "       la      1,0\n"
291                 "       la      2,4\n"
292                 "       csp     0,2\n"
293                 "0:     la      %0,0\n"
294                 "1:\n"
295                 EX_TABLE(0b,1b)
296                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
297         if (!rc)
298                 machine_flags |= MACHINE_FLAG_CSP;
299 #endif
300 }
301
302 static __init void detect_diag9c(void)
303 {
304         unsigned int cpu_address;
305         int rc;
306
307         cpu_address = stap();
308         asm volatile(
309                 "       diag    %2,0,0x9c\n"
310                 "0:     la      %0,0\n"
311                 "1:\n"
312                 EX_TABLE(0b,1b)
313                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
314         if (!rc)
315                 machine_flags |= MACHINE_FLAG_DIAG9C;
316 }
317
318 static __init void detect_diag44(void)
319 {
320 #ifdef CONFIG_64BIT
321         int rc;
322
323         asm volatile(
324                 "       diag    0,0,0x44\n"
325                 "0:     la      %0,0\n"
326                 "1:\n"
327                 EX_TABLE(0b,1b)
328                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
329         if (!rc)
330                 machine_flags |= MACHINE_FLAG_DIAG44;
331 #endif
332 }
333
334 static __init void detect_machine_facilities(void)
335 {
336 #ifdef CONFIG_64BIT
337         unsigned int facilities;
338
339         facilities = stfl();
340         if (facilities & (1 << 28))
341                 machine_flags |= MACHINE_FLAG_IDTE;
342         if (facilities & (1 << 23))
343                 machine_flags |= MACHINE_FLAG_PFMF;
344         if (facilities & (1 << 4))
345                 machine_flags |= MACHINE_FLAG_MVCOS;
346 #endif
347 }
348
349 static __init void rescue_initrd(void)
350 {
351 #ifdef CONFIG_BLK_DEV_INITRD
352         /*
353          * Move the initrd right behind the bss section in case it starts
354          * within the bss section. So we don't overwrite it when the bss
355          * section gets cleared.
356          */
357         if (!INITRD_START || !INITRD_SIZE)
358                 return;
359         if (INITRD_START >= (unsigned long) __bss_stop)
360                 return;
361         memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE);
362         INITRD_START = (unsigned long) __bss_stop;
363 #endif
364 }
365
366 /* Set up boot command line */
367 static void __init setup_boot_command_line(void)
368 {
369         char *parm = NULL;
370
371         /* copy arch command line */
372         strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
373
374         /* append IPL PARM data to the boot command line */
375         if (MACHINE_IS_VM) {
376                 parm = boot_command_line + strlen(boot_command_line);
377                 *parm++ = ' ';
378                 get_ipl_vmparm(parm);
379                 if (parm[0] == '=')
380                         memmove(boot_command_line, parm + 1, strlen(parm));
381         }
382 }
383
384
385 /*
386  * Save ipl parameters, clear bss memory, initialize storage keys
387  * and create a kernel NSS at startup if the SAVESYS= parm is defined
388  */
389 void __init startup_init(void)
390 {
391         reset_tod_clock();
392         ipl_save_parameters();
393         rescue_initrd();
394         clear_bss_section();
395         init_kernel_storage_key();
396         lockdep_init();
397         lockdep_off();
398         sort_main_extable();
399         setup_lowcore_early();
400         detect_machine_type();
401         ipl_update_parameters();
402         setup_boot_command_line();
403         create_kernel_nss();
404         detect_mvpg();
405         detect_ieee();
406         detect_csp();
407         detect_diag9c();
408         detect_diag44();
409         detect_machine_facilities();
410         setup_hpage();
411         sclp_facilities_detect();
412         detect_memory_layout(memory_chunk);
413         S390_lowcore.machine_flags = machine_flags;
414 #ifdef CONFIG_DYNAMIC_FTRACE
415         S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
416 #endif
417         lockdep_on();
418 }