2 * arch/s390/kernel/early.c
4 * Copyright IBM Corp. 2007
5 * Author(s): Hongjie Yang <hongjie@us.ibm.com>,
6 * Heiko Carstens <heiko.carstens@de.ibm.com>
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>
18 #include <asm/lowcore.h>
19 #include <asm/processor.h>
20 #include <asm/sections.h>
21 #include <asm/setup.h>
22 #include <asm/cpcmd.h>
27 * Create a Kernel NSS if the SAVESYS= parameter is defined
29 #define DEFSYS_CMD_SIZE 96
30 #define SAVESYS_CMD_SIZE 32
32 char kernel_nss_name
[NSS_NAME_SIZE
+ 1];
34 #ifdef CONFIG_SHARED_KERNEL
35 static noinline __init
void create_kernel_nss(void)
37 unsigned int i
, stext_pfn
, eshared_pfn
, end_pfn
, min_size
;
38 #ifdef CONFIG_BLK_DEV_INITRD
39 unsigned int sinitrd_pfn
, einitrd_pfn
;
43 char upper_command_line
[COMMAND_LINE_SIZE
];
44 char defsys_cmd
[DEFSYS_CMD_SIZE
];
45 char savesys_cmd
[SAVESYS_CMD_SIZE
];
47 /* Do nothing if we are not running under VM */
51 /* Convert COMMAND_LINE to upper case */
52 for (i
= 0; i
< strlen(COMMAND_LINE
); i
++)
53 upper_command_line
[i
] = toupper(COMMAND_LINE
[i
]);
55 savesys_ptr
= strstr(upper_command_line
, "SAVESYS=");
60 savesys_ptr
+= 8; /* Point to the beginning of the NSS name */
61 for (i
= 0; i
< NSS_NAME_SIZE
; i
++) {
62 if (savesys_ptr
[i
] == ' ' || savesys_ptr
[i
] == '\0')
64 kernel_nss_name
[i
] = savesys_ptr
[i
];
67 stext_pfn
= PFN_DOWN(__pa(&_stext
));
68 eshared_pfn
= PFN_DOWN(__pa(&_eshared
));
69 end_pfn
= PFN_UP(__pa(&_end
));
70 min_size
= end_pfn
<< 2;
72 sprintf(defsys_cmd
, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
73 kernel_nss_name
, stext_pfn
- 1, stext_pfn
, eshared_pfn
- 1,
74 eshared_pfn
, end_pfn
);
76 #ifdef CONFIG_BLK_DEV_INITRD
77 if (INITRD_START
&& INITRD_SIZE
) {
78 sinitrd_pfn
= PFN_DOWN(__pa(INITRD_START
));
79 einitrd_pfn
= PFN_UP(__pa(INITRD_START
+ INITRD_SIZE
));
80 min_size
= einitrd_pfn
<< 2;
81 sprintf(defsys_cmd
, "%s EW %.5X-%.5X", defsys_cmd
,
82 sinitrd_pfn
, einitrd_pfn
);
86 sprintf(defsys_cmd
, "%s EW MINSIZE=%.7iK", defsys_cmd
, min_size
);
87 sprintf(savesys_cmd
, "SAVESYS %s \n IPL %s",
88 kernel_nss_name
, kernel_nss_name
);
90 __cpcmd(defsys_cmd
, NULL
, 0, &response
);
93 kernel_nss_name
[0] = '\0';
97 __cpcmd(savesys_cmd
, NULL
, 0, &response
);
99 if (response
!= strlen(savesys_cmd
)) {
100 kernel_nss_name
[0] = '\0';
104 ipl_flags
= IPL_NSS_VALID
;
107 #else /* CONFIG_SHARED_KERNEL */
109 static inline void create_kernel_nss(void) { }
111 #endif /* CONFIG_SHARED_KERNEL */
116 static noinline __init
void clear_bss_section(void)
118 memset(__bss_start
, 0, __bss_stop
- __bss_start
);
122 * Initialize storage key for kernel pages
124 static noinline __init
void init_kernel_storage_key(void)
126 unsigned long end_pfn
, init_pfn
;
128 end_pfn
= PFN_UP(__pa(&_end
));
130 for (init_pfn
= 0 ; init_pfn
< end_pfn
; init_pfn
++)
131 page_set_storage_key(init_pfn
<< PAGE_SHIFT
, PAGE_DEFAULT_KEY
);
134 static noinline __init
void detect_machine_type(void)
136 struct cpuinfo_S390
*cpuinfo
= &S390_lowcore
.cpu_data
;
138 get_cpu_id(&S390_lowcore
.cpu_data
.cpu_id
);
140 /* Running under z/VM ? */
141 if (cpuinfo
->cpu_id
.version
== 0xff)
144 /* Running on a P/390 ? */
145 if (cpuinfo
->cpu_id
.machine
== 0x7490)
150 static noinline __init
int memory_fast_detect(void)
152 unsigned long val0
= 0;
153 unsigned long val1
= 0xc;
156 if (ipl_flags
& IPL_NSS_VALID
)
160 " diag %1,%2,0x260\n"
164 : "+d" (ret
), "+d" (val0
), "+d" (val1
) : : "cc");
166 if (ret
|| val0
!= val1
)
169 memory_chunk
[0].size
= val0
+ 1;
173 static inline int memory_fast_detect(void)
179 static inline __init
unsigned long __tprot(unsigned long addr
)
189 : "+d" (cc
) : "a" (addr
) : "cc");
190 return (unsigned long)cc
;
193 /* Checking memory in 128KB increments. */
194 #define CHUNK_INCR (1UL << 17)
195 #define ADDR2G (1UL << 31)
197 static noinline __init
void find_memory_chunks(unsigned long memsize
)
199 unsigned long addr
= 0, old_addr
= 0;
200 unsigned long old_cc
= CHUNK_READ_WRITE
;
204 while (chunk
< MEMORY_CHUNKS
) {
206 while (cc
== old_cc
) {
208 if (memsize
&& addr
>= memsize
)
217 if (old_addr
!= addr
&&
218 (old_cc
== CHUNK_READ_WRITE
|| old_cc
== CHUNK_READ_ONLY
)) {
219 memory_chunk
[chunk
].addr
= old_addr
;
220 memory_chunk
[chunk
].size
= addr
- old_addr
;
221 memory_chunk
[chunk
].type
= old_cc
;
233 * Finish memory detection at the first hole
234 * if storage size is unknown.
236 if (cc
== -1UL && !memsize
)
238 if (memsize
&& addr
>= memsize
)
243 static __init
void early_pgm_check_handler(void)
246 const struct exception_table_entry
*fixup
;
248 addr
= S390_lowcore
.program_old_psw
.addr
;
249 fixup
= search_exception_tables(addr
& PSW_ADDR_INSN
);
252 S390_lowcore
.program_old_psw
.addr
= fixup
->fixup
| PSW_ADDR_AMODE
;
255 static noinline __init
void setup_lowcore_early(void)
259 psw
.mask
= PSW_BASE_BITS
| PSW_DEFAULT_KEY
;
260 psw
.addr
= PSW_ADDR_AMODE
| (unsigned long) s390_base_ext_handler
;
261 S390_lowcore
.external_new_psw
= psw
;
262 psw
.addr
= PSW_ADDR_AMODE
| (unsigned long) s390_base_pgm_handler
;
263 S390_lowcore
.program_new_psw
= psw
;
264 s390_base_pgm_handler_fn
= early_pgm_check_handler
;
268 * Save ipl parameters, clear bss memory, initialize storage keys
269 * and create a kernel NSS at startup if the SAVESYS= parm is defined
271 void __init
startup_init(void)
273 unsigned long long memsize
;
275 ipl_save_parameters();
277 init_kernel_storage_key();
280 detect_machine_type();
283 setup_lowcore_early();
284 sclp_read_info_early();
285 sclp_facilities_detect();
286 memsize
= sclp_memory_detect();
289 * Can't deal with more than 2G in 31 bit addressing mode, so
290 * limit the value in order to avoid strange side effects.
292 if (memsize
> ADDR2G
)
295 if (memory_fast_detect() < 0)
296 find_memory_chunks((unsigned long) memsize
);