1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _ASM_S390_RUNTIME_CONST_H
 3#define _ASM_S390_RUNTIME_CONST_H
 4
 5#include <linux/uaccess.h>
 6
 7#define runtime_const_ptr(sym)					\
 8({								\
 9	typeof(sym) __ret;					\
10								\
11	asm_inline(						\
12		"0:	iihf	%[__ret],%[c1]\n"		\
13		"	iilf	%[__ret],%[c2]\n"		\
14		".pushsection runtime_ptr_" #sym ",\"a\"\n"	\
15		".long 0b - .\n"				\
16		".popsection"					\
17		: [__ret] "=d" (__ret)				\
18		: [c1] "i" (0x01234567UL),			\
19		  [c2] "i" (0x89abcdefUL));			\
20	__ret;							\
21})
22
23#define runtime_const_shift_right_32(val, sym)			\
24({								\
25	unsigned int __ret = (val);				\
26								\
27	asm_inline(						\
28		"0:	srl	%[__ret],12\n"			\
29		".pushsection runtime_shift_" #sym ",\"a\"\n"	\
30		".long 0b - .\n"				\
31		".popsection"					\
32		: [__ret] "+d" (__ret));			\
33	__ret;							\
34})
35
36#define runtime_const_init(type, sym) do {			\
37	extern s32 __start_runtime_##type##_##sym[];		\
38	extern s32 __stop_runtime_##type##_##sym[];		\
39								\
40	runtime_const_fixup(__runtime_fixup_##type,		\
41			    (unsigned long)(sym),		\
42			    __start_runtime_##type##_##sym,	\
43			    __stop_runtime_##type##_##sym);	\
44} while (0)
45
46/* 32-bit immediate for iihf and iilf in bits in I2 field */
47static inline void __runtime_fixup_32(u32 *p, unsigned int val)
48{
49	s390_kernel_write(p, &val, sizeof(val));
50}
51
52static inline void __runtime_fixup_ptr(void *where, unsigned long val)
53{
54	__runtime_fixup_32(where + 2, val >> 32);
55	__runtime_fixup_32(where + 8, val);
56}
57
58/* Immediate value is lower 12 bits of D2 field of srl */
59static inline void __runtime_fixup_shift(void *where, unsigned long val)
60{
61	u32 insn = *(u32 *)where;
62
63	insn &= 0xfffff000;
64	insn |= (val & 63);
65	s390_kernel_write(where, &insn, sizeof(insn));
66}
67
68static inline void runtime_const_fixup(void (*fn)(void *, unsigned long),
69				       unsigned long val, s32 *start, s32 *end)
70{
71	while (start < end) {
72		fn(*start + (void *)start, val);
73		start++;
74	}
75}
76
77#endif /* _ASM_S390_RUNTIME_CONST_H */