Merge git://git.infradead.org/mtd-2.6
[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/init.h>
10 #include <linux/errno.h>
11 #include <linux/string.h>
12 #include <linux/ctype.h>
13 #include <linux/lockdep.h>
14 #include <linux/module.h>
15 #include <linux/pfn.h>
16 #include <linux/uaccess.h>
17 #include <asm/ebcdic.h>
18 #include <asm/ipl.h>
19 #include <asm/lowcore.h>
20 #include <asm/processor.h>
21 #include <asm/sections.h>
22 #include <asm/setup.h>
23 #include <asm/cpcmd.h>
24 #include <asm/sclp.h>
25 #include "entry.h"
26
27 /*
28  * Create a Kernel NSS if the SAVESYS= parameter is defined
29  */
30 #define DEFSYS_CMD_SIZE         128
31 #define SAVESYS_CMD_SIZE        32
32
33 char kernel_nss_name[NSS_NAME_SIZE + 1];
34
35 static void __init setup_boot_command_line(void);
36
37
38 #ifdef CONFIG_SHARED_KERNEL
39 int __init savesys_ipl_nss(char *cmd, const int cmdlen);
40
41 asm(
42         "       .section .init.text,\"ax\",@progbits\n"
43         "       .align  4\n"
44         "       .type   savesys_ipl_nss, @function\n"
45         "savesys_ipl_nss:\n"
46 #ifdef CONFIG_64BIT
47         "       stmg    6,15,48(15)\n"
48         "       lgr     14,3\n"
49         "       sam31\n"
50         "       diag    2,14,0x8\n"
51         "       sam64\n"
52         "       lgr     2,14\n"
53         "       lmg     6,15,48(15)\n"
54 #else
55         "       stm     6,15,24(15)\n"
56         "       lr      14,3\n"
57         "       diag    2,14,0x8\n"
58         "       lr      2,14\n"
59         "       lm      6,15,24(15)\n"
60 #endif
61         "       br      14\n"
62         "       .size   savesys_ipl_nss, .-savesys_ipl_nss\n");
63
64 static noinline __init void create_kernel_nss(void)
65 {
66         unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
67 #ifdef CONFIG_BLK_DEV_INITRD
68         unsigned int sinitrd_pfn, einitrd_pfn;
69 #endif
70         int response;
71         size_t len;
72         char *savesys_ptr;
73         char upper_command_line[COMMAND_LINE_SIZE];
74         char defsys_cmd[DEFSYS_CMD_SIZE];
75         char savesys_cmd[SAVESYS_CMD_SIZE];
76
77         /* Do nothing if we are not running under VM */
78         if (!MACHINE_IS_VM)
79                 return;
80
81         /* Convert COMMAND_LINE to upper case */
82         for (i = 0; i < strlen(boot_command_line); i++)
83                 upper_command_line[i] = toupper(boot_command_line[i]);
84
85         savesys_ptr = strstr(upper_command_line, "SAVESYS=");
86
87         if (!savesys_ptr)
88                 return;
89
90         savesys_ptr += 8;    /* Point to the beginning of the NSS name */
91         for (i = 0; i < NSS_NAME_SIZE; i++) {
92                 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
93                         break;
94                 kernel_nss_name[i] = savesys_ptr[i];
95         }
96
97         stext_pfn = PFN_DOWN(__pa(&_stext));
98         eshared_pfn = PFN_DOWN(__pa(&_eshared));
99         end_pfn = PFN_UP(__pa(&_end));
100         min_size = end_pfn << 2;
101
102         sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
103                 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
104                 eshared_pfn, end_pfn);
105
106 #ifdef CONFIG_BLK_DEV_INITRD
107         if (INITRD_START && INITRD_SIZE) {
108                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
109                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
110                 min_size = einitrd_pfn << 2;
111                 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
112                 sinitrd_pfn, einitrd_pfn);
113         }
114 #endif
115
116         sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13",
117                 defsys_cmd, min_size);
118         sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
119                 kernel_nss_name, kernel_nss_name);
120
121         __cpcmd(defsys_cmd, NULL, 0, &response);
122
123         if (response != 0) {
124                 kernel_nss_name[0] = '\0';
125                 return;
126         }
127
128         len = strlen(savesys_cmd);
129         ASCEBC(savesys_cmd, len);
130         response = savesys_ipl_nss(savesys_cmd, len);
131
132         /* On success: response is equal to the command size,
133          *             max SAVESYS_CMD_SIZE
134          * On error: response contains the numeric portion of cp error message.
135          *           for SAVESYS it will be >= 263
136          */
137         if (response > SAVESYS_CMD_SIZE) {
138                 kernel_nss_name[0] = '\0';
139                 return;
140         }
141
142         /* re-setup boot command line with new ipl vm parms */
143         ipl_update_parameters();
144         setup_boot_command_line();
145
146         ipl_flags = IPL_NSS_VALID;
147 }
148
149 #else /* CONFIG_SHARED_KERNEL */
150
151 static inline void create_kernel_nss(void) { }
152
153 #endif /* CONFIG_SHARED_KERNEL */
154
155 /*
156  * Clear bss memory
157  */
158 static noinline __init void clear_bss_section(void)
159 {
160         memset(__bss_start, 0, __bss_stop - __bss_start);
161 }
162
163 /*
164  * Initialize storage key for kernel pages
165  */
166 static noinline __init void init_kernel_storage_key(void)
167 {
168         unsigned long end_pfn, init_pfn;
169
170         end_pfn = PFN_UP(__pa(&_end));
171
172         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
173                 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
174 }
175
176 static noinline __init void detect_machine_type(void)
177 {
178         struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
179
180         get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
181
182         /* Running under z/VM ? */
183         if (cpuinfo->cpu_id.version == 0xff)
184                 machine_flags |= MACHINE_FLAG_VM;
185
186         /* Running under KVM ? */
187         if (cpuinfo->cpu_id.version == 0xfe)
188                 machine_flags |= MACHINE_FLAG_KVM;
189 }
190
191 static __init void early_pgm_check_handler(void)
192 {
193         unsigned long addr;
194         const struct exception_table_entry *fixup;
195
196         addr = S390_lowcore.program_old_psw.addr;
197         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
198         if (!fixup)
199                 disabled_wait(0);
200         S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
201 }
202
203 static noinline __init void setup_lowcore_early(void)
204 {
205         psw_t psw;
206
207         psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
208         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
209         S390_lowcore.external_new_psw = psw;
210         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
211         S390_lowcore.program_new_psw = psw;
212         s390_base_pgm_handler_fn = early_pgm_check_handler;
213 }
214
215 static noinline __init void setup_hpage(void)
216 {
217 #ifndef CONFIG_DEBUG_PAGEALLOC
218         unsigned int facilities;
219
220         facilities = stfl();
221         if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
222                 return;
223         machine_flags |= MACHINE_FLAG_HPAGE;
224         __ctl_set_bit(0, 23);
225 #endif
226 }
227
228 static __init void detect_mvpg(void)
229 {
230 #ifndef CONFIG_64BIT
231         int rc;
232
233         asm volatile(
234                 "       la      0,0\n"
235                 "       mvpg    %2,%2\n"
236                 "0:     la      %0,0\n"
237                 "1:\n"
238                 EX_TABLE(0b,1b)
239                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
240         if (!rc)
241                 machine_flags |= MACHINE_FLAG_MVPG;
242 #endif
243 }
244
245 static __init void detect_ieee(void)
246 {
247 #ifndef CONFIG_64BIT
248         int rc, tmp;
249
250         asm volatile(
251                 "       efpc    %1,0\n"
252                 "0:     la      %0,0\n"
253                 "1:\n"
254                 EX_TABLE(0b,1b)
255                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
256         if (!rc)
257                 machine_flags |= MACHINE_FLAG_IEEE;
258 #endif
259 }
260
261 static __init void detect_csp(void)
262 {
263 #ifndef CONFIG_64BIT
264         int rc;
265
266         asm volatile(
267                 "       la      0,0\n"
268                 "       la      1,0\n"
269                 "       la      2,4\n"
270                 "       csp     0,2\n"
271                 "0:     la      %0,0\n"
272                 "1:\n"
273                 EX_TABLE(0b,1b)
274                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
275         if (!rc)
276                 machine_flags |= MACHINE_FLAG_CSP;
277 #endif
278 }
279
280 static __init void detect_diag9c(void)
281 {
282         unsigned int cpu_address;
283         int rc;
284
285         cpu_address = stap();
286         asm volatile(
287                 "       diag    %2,0,0x9c\n"
288                 "0:     la      %0,0\n"
289                 "1:\n"
290                 EX_TABLE(0b,1b)
291                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
292         if (!rc)
293                 machine_flags |= MACHINE_FLAG_DIAG9C;
294 }
295
296 static __init void detect_diag44(void)
297 {
298 #ifdef CONFIG_64BIT
299         int rc;
300
301         asm volatile(
302                 "       diag    0,0,0x44\n"
303                 "0:     la      %0,0\n"
304                 "1:\n"
305                 EX_TABLE(0b,1b)
306                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
307         if (!rc)
308                 machine_flags |= MACHINE_FLAG_DIAG44;
309 #endif
310 }
311
312 static __init void detect_machine_facilities(void)
313 {
314 #ifdef CONFIG_64BIT
315         unsigned int facilities;
316
317         facilities = stfl();
318         if (facilities & (1 << 28))
319                 machine_flags |= MACHINE_FLAG_IDTE;
320         if (facilities & (1 << 23))
321                 machine_flags |= MACHINE_FLAG_PFMF;
322         if (facilities & (1 << 4))
323                 machine_flags |= MACHINE_FLAG_MVCOS;
324 #endif
325 }
326
327 static __init void rescue_initrd(void)
328 {
329 #ifdef CONFIG_BLK_DEV_INITRD
330         /*
331          * Move the initrd right behind the bss section in case it starts
332          * within the bss section. So we don't overwrite it when the bss
333          * section gets cleared.
334          */
335         if (!INITRD_START || !INITRD_SIZE)
336                 return;
337         if (INITRD_START >= (unsigned long) __bss_stop)
338                 return;
339         memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE);
340         INITRD_START = (unsigned long) __bss_stop;
341 #endif
342 }
343
344 /* Set up boot command line */
345 static void __init setup_boot_command_line(void)
346 {
347         char *parm = NULL;
348
349         /* copy arch command line */
350         strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
351         boot_command_line[ARCH_COMMAND_LINE_SIZE - 1] = 0;
352
353         /* append IPL PARM data to the boot command line */
354         if (MACHINE_IS_VM) {
355                 parm = boot_command_line + strlen(boot_command_line);
356                 *parm++ = ' ';
357                 get_ipl_vmparm(parm);
358                 if (parm[0] == '=')
359                         memmove(boot_command_line, parm + 1, strlen(parm));
360         }
361 }
362
363
364 /*
365  * Save ipl parameters, clear bss memory, initialize storage keys
366  * and create a kernel NSS at startup if the SAVESYS= parm is defined
367  */
368 void __init startup_init(void)
369 {
370         ipl_save_parameters();
371         rescue_initrd();
372         clear_bss_section();
373         init_kernel_storage_key();
374         lockdep_init();
375         lockdep_off();
376         sort_main_extable();
377         setup_lowcore_early();
378         detect_machine_type();
379         ipl_update_parameters();
380         setup_boot_command_line();
381         create_kernel_nss();
382         detect_mvpg();
383         detect_ieee();
384         detect_csp();
385         detect_diag9c();
386         detect_diag44();
387         detect_machine_facilities();
388         setup_hpage();
389         sclp_facilities_detect();
390         detect_memory_layout(memory_chunk);
391         lockdep_on();
392 }