Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
[sfrench/cifs-2.6.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
87 static __initdata char upper_command_line[COMMAND_LINE_SIZE];
88
89 static 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         size_t len;
97         char *savesys_ptr;
98         char defsys_cmd[DEFSYS_CMD_SIZE];
99         char savesys_cmd[SAVESYS_CMD_SIZE];
100
101         /* Do nothing if we are not running under VM */
102         if (!MACHINE_IS_VM)
103                 return;
104
105         /* Convert COMMAND_LINE to upper case */
106         for (i = 0; i < strlen(boot_command_line); i++)
107                 upper_command_line[i] = toupper(boot_command_line[i]);
108
109         savesys_ptr = strstr(upper_command_line, "SAVESYS=");
110
111         if (!savesys_ptr)
112                 return;
113
114         savesys_ptr += 8;    /* Point to the beginning of the NSS name */
115         for (i = 0; i < NSS_NAME_SIZE; i++) {
116                 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
117                         break;
118                 kernel_nss_name[i] = savesys_ptr[i];
119         }
120
121         stext_pfn = PFN_DOWN(__pa(&_stext));
122         eshared_pfn = PFN_DOWN(__pa(&_eshared));
123         end_pfn = PFN_UP(__pa(&_end));
124         min_size = end_pfn << 2;
125
126         sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
127                 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
128                 eshared_pfn, end_pfn);
129
130 #ifdef CONFIG_BLK_DEV_INITRD
131         if (INITRD_START && INITRD_SIZE) {
132                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
133                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
134                 min_size = einitrd_pfn << 2;
135                 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
136                 sinitrd_pfn, einitrd_pfn);
137         }
138 #endif
139
140         sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13",
141                 defsys_cmd, min_size);
142         sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
143                 kernel_nss_name, kernel_nss_name);
144
145         __cpcmd(defsys_cmd, NULL, 0, &response);
146
147         if (response != 0) {
148                 pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
149                         response);
150                 kernel_nss_name[0] = '\0';
151                 return;
152         }
153
154         len = strlen(savesys_cmd);
155         ASCEBC(savesys_cmd, len);
156         response = savesys_ipl_nss(savesys_cmd, len);
157
158         /* On success: response is equal to the command size,
159          *             max SAVESYS_CMD_SIZE
160          * On error: response contains the numeric portion of cp error message.
161          *           for SAVESYS it will be >= 263
162          *           for missing privilege class, it will be 1
163          */
164         if (response > SAVESYS_CMD_SIZE || response == 1) {
165                 pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
166                         response);
167                 kernel_nss_name[0] = '\0';
168                 return;
169         }
170
171         /* re-initialize cputime accounting. */
172         sched_clock_base_cc = get_clock();
173         S390_lowcore.last_update_clock = sched_clock_base_cc;
174         S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
175         S390_lowcore.user_timer = 0;
176         S390_lowcore.system_timer = 0;
177         asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
178
179         /* re-setup boot command line with new ipl vm parms */
180         ipl_update_parameters();
181         setup_boot_command_line();
182
183         ipl_flags = IPL_NSS_VALID;
184 }
185
186 #else /* CONFIG_SHARED_KERNEL */
187
188 static inline void create_kernel_nss(void) { }
189
190 #endif /* CONFIG_SHARED_KERNEL */
191
192 /*
193  * Clear bss memory
194  */
195 static noinline __init void clear_bss_section(void)
196 {
197         memset(__bss_start, 0, __bss_stop - __bss_start);
198 }
199
200 /*
201  * Initialize storage key for kernel pages
202  */
203 static noinline __init void init_kernel_storage_key(void)
204 {
205         unsigned long end_pfn, init_pfn;
206
207         end_pfn = PFN_UP(__pa(&_end));
208
209         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
210                 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
211 }
212
213 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
214
215 static noinline __init void detect_machine_type(void)
216 {
217         /* No VM information? Looks like LPAR */
218         if (stsi(&vmms, 3, 2, 2) == -ENOSYS)
219                 return;
220         if (!vmms.count)
221                 return;
222
223         /* Running under KVM? If not we assume z/VM */
224         if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
225                 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
226         else
227                 S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
228 }
229
230 static __init void early_pgm_check_handler(void)
231 {
232         unsigned long addr;
233         const struct exception_table_entry *fixup;
234
235         addr = S390_lowcore.program_old_psw.addr;
236         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
237         if (!fixup)
238                 disabled_wait(0);
239         S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
240 }
241
242 static noinline __init void setup_lowcore_early(void)
243 {
244         psw_t psw;
245
246         psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
247         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
248         S390_lowcore.external_new_psw = psw;
249         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
250         S390_lowcore.program_new_psw = psw;
251         s390_base_pgm_handler_fn = early_pgm_check_handler;
252 }
253
254 static noinline __init void setup_hpage(void)
255 {
256 #ifndef CONFIG_DEBUG_PAGEALLOC
257         unsigned int facilities;
258
259         facilities = stfl();
260         if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
261                 return;
262         S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
263         __ctl_set_bit(0, 23);
264 #endif
265 }
266
267 static __init void detect_mvpg(void)
268 {
269 #ifndef CONFIG_64BIT
270         int rc;
271
272         asm volatile(
273                 "       la      0,0\n"
274                 "       mvpg    %2,%2\n"
275                 "0:     la      %0,0\n"
276                 "1:\n"
277                 EX_TABLE(0b,1b)
278                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
279         if (!rc)
280                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
281 #endif
282 }
283
284 static __init void detect_ieee(void)
285 {
286 #ifndef CONFIG_64BIT
287         int rc, tmp;
288
289         asm volatile(
290                 "       efpc    %1,0\n"
291                 "0:     la      %0,0\n"
292                 "1:\n"
293                 EX_TABLE(0b,1b)
294                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
295         if (!rc)
296                 S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
297 #endif
298 }
299
300 static __init void detect_csp(void)
301 {
302 #ifndef CONFIG_64BIT
303         int rc;
304
305         asm volatile(
306                 "       la      0,0\n"
307                 "       la      1,0\n"
308                 "       la      2,4\n"
309                 "       csp     0,2\n"
310                 "0:     la      %0,0\n"
311                 "1:\n"
312                 EX_TABLE(0b,1b)
313                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
314         if (!rc)
315                 S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
316 #endif
317 }
318
319 static __init void detect_diag9c(void)
320 {
321         unsigned int cpu_address;
322         int rc;
323
324         cpu_address = stap();
325         asm volatile(
326                 "       diag    %2,0,0x9c\n"
327                 "0:     la      %0,0\n"
328                 "1:\n"
329                 EX_TABLE(0b,1b)
330                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
331         if (!rc)
332                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
333 }
334
335 static __init void detect_diag44(void)
336 {
337 #ifdef CONFIG_64BIT
338         int rc;
339
340         asm volatile(
341                 "       diag    0,0,0x44\n"
342                 "0:     la      %0,0\n"
343                 "1:\n"
344                 EX_TABLE(0b,1b)
345                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
346         if (!rc)
347                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
348 #endif
349 }
350
351 static __init void detect_machine_facilities(void)
352 {
353 #ifdef CONFIG_64BIT
354         unsigned int facilities;
355
356         facilities = stfl();
357         if (facilities & (1 << 28))
358                 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
359         if (facilities & (1 << 23))
360                 S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
361         if (facilities & (1 << 4))
362                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
363 #endif
364 }
365
366 static __init void rescue_initrd(void)
367 {
368 #ifdef CONFIG_BLK_DEV_INITRD
369         /*
370          * Move the initrd right behind the bss section in case it starts
371          * within the bss section. So we don't overwrite it when the bss
372          * section gets cleared.
373          */
374         if (!INITRD_START || !INITRD_SIZE)
375                 return;
376         if (INITRD_START >= (unsigned long) __bss_stop)
377                 return;
378         memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE);
379         INITRD_START = (unsigned long) __bss_stop;
380 #endif
381 }
382
383 /* Set up boot command line */
384 static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
385 {
386         char *parm, *delim;
387         size_t rc, len;
388
389         len = strlen(boot_command_line);
390
391         delim = boot_command_line + len;        /* '\0' character position */
392         parm  = boot_command_line + len + 1;    /* append right after '\0' */
393
394         rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
395         if (rc) {
396                 if (*parm == '=')
397                         memmove(boot_command_line, parm + 1, rc);
398                 else
399                         *delim = ' ';           /* replace '\0' with space */
400         }
401 }
402
403 static void __init setup_boot_command_line(void)
404 {
405         /* copy arch command line */
406         strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
407
408         /* append IPL PARM data to the boot command line */
409         if (MACHINE_IS_VM)
410                 append_to_cmdline(append_ipl_vmparm);
411
412         append_to_cmdline(append_ipl_scpdata);
413 }
414
415
416 /*
417  * Save ipl parameters, clear bss memory, initialize storage keys
418  * and create a kernel NSS at startup if the SAVESYS= parm is defined
419  */
420 void __init startup_init(void)
421 {
422         reset_tod_clock();
423         ipl_save_parameters();
424         rescue_initrd();
425         clear_bss_section();
426         init_kernel_storage_key();
427         lockdep_init();
428         lockdep_off();
429         sort_main_extable();
430         setup_lowcore_early();
431         detect_machine_type();
432         ipl_update_parameters();
433         setup_boot_command_line();
434         create_kernel_nss();
435         detect_mvpg();
436         detect_ieee();
437         detect_csp();
438         detect_diag9c();
439         detect_diag44();
440         detect_machine_facilities();
441         setup_hpage();
442         sclp_facilities_detect();
443         detect_memory_layout(memory_chunk);
444 #ifdef CONFIG_DYNAMIC_FTRACE
445         S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
446 #endif
447         lockdep_on();
448 }