1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _VDSO_DATAPAGE_H
3 #define _VDSO_DATAPAGE_H
4 #ifdef __KERNEL__
5 
6 /*
7  * Copyright (C) 2002 Peter Bergner <bergner@vnet.ibm.com>, IBM
8  * Copyright (C) 2005 Benjamin Herrenschmidy <benh@kernel.crashing.org>,
9  * 		      IBM Corp.
10  */
11 
12 
13 /*
14  * Note about this structure:
15  *
16  * This structure was historically called systemcfg and exposed to
17  * userland via /proc/ppc64/systemcfg. Unfortunately, this became an
18  * ABI issue as some proprietary software started relying on being able
19  * to mmap() it, thus we have to keep the base layout at least for a
20  * few kernel versions.
21  *
22  * However, since ppc32 doesn't suffer from this backward handicap,
23  * a simpler version of the data structure is used there with only the
24  * fields actually used by the vDSO.
25  *
26  */
27 
28 /*
29  * If the major version changes we are incompatible.
30  * Minor version changes are a hint.
31  */
32 #define SYSTEMCFG_MAJOR 1
33 #define SYSTEMCFG_MINOR 1
34 
35 #ifndef __ASSEMBLY__
36 
37 #include <linux/unistd.h>
38 #include <linux/time.h>
39 
40 #define SYSCALL_MAP_SIZE      ((NR_syscalls + 31) / 32)
41 
42 /*
43  * So here is the ppc64 backward compatible version
44  */
45 
46 #ifdef CONFIG_PPC64
47 
48 struct vdso_data {
49 	__u8  eye_catcher[16];		/* Eyecatcher: SYSTEMCFG:PPC64	0x00 */
50 	struct {			/* Systemcfg version numbers	     */
51 		__u32 major;		/* Major number			0x10 */
52 		__u32 minor;		/* Minor number			0x14 */
53 	} version;
54 
55 	/* Note about the platform flags: it now only contains the lpar
56 	 * bit. The actual platform number is dead and buried
57 	 */
58 	__u32 platform;			/* Platform flags		0x18 */
59 	__u32 processor;		/* Processor type		0x1C */
60 	__u64 processorCount;		/* # of physical processors	0x20 */
61 	__u64 physicalMemorySize;	/* Size of real memory(B)	0x28 */
62 	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
63 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
64 	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
65 	__u64 stamp_xsec;		/*				0x48 */
66 	__u64 tb_update_count;		/* Timebase atomicity ctr	0x50 */
67 	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
68 	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
69 	__u32 dcache_size;		/* L1 d-cache size		0x60 */
70 	__u32 dcache_line_size;		/* L1 d-cache line size		0x64 */
71 	__u32 icache_size;		/* L1 i-cache size		0x68 */
72 	__u32 icache_line_size;		/* L1 i-cache line size		0x6C */
73 
74 	/* those additional ones don't have to be located anywhere
75 	 * special as they were not part of the original systemcfg
76 	 */
77 	__u32 dcache_block_size;		/* L1 d-cache block size     */
78 	__u32 icache_block_size;		/* L1 i-cache block size     */
79 	__u32 dcache_log_block_size;		/* L1 d-cache log block size */
80 	__u32 icache_log_block_size;		/* L1 i-cache log block size */
81 	__u32 stamp_sec_fraction;		/* fractional seconds of stamp_xtime */
82 	__s32 wtom_clock_nsec;			/* Wall to monotonic clock nsec */
83 	__s64 wtom_clock_sec;			/* Wall to monotonic clock sec */
84 	__s64 stamp_xtime_sec;			/* xtime secs as at tb_orig_stamp */
85 	__s64 stamp_xtime_nsec;			/* xtime nsecs as at tb_orig_stamp */
86 	__u32 hrtimer_res;			/* hrtimer resolution */
87    	__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls  */
88    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
89 };
90 
91 #else /* CONFIG_PPC64 */
92 
93 /*
94  * And here is the simpler 32 bits version
95  */
96 struct vdso_data {
97 	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
98 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
99 	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
100 	__u64 stamp_xsec;		/*				0x48 */
101 	__u32 tb_update_count;		/* Timebase atomicity ctr	0x50 */
102 	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
103 	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
104 	__s32 wtom_clock_sec;			/* Wall to monotonic clock */
105 	__s32 wtom_clock_nsec;
106 	__s32 stamp_xtime_sec;		/* xtime seconds as at tb_orig_stamp */
107 	__s32 stamp_xtime_nsec;		/* xtime nsecs as at tb_orig_stamp */
108 	__u32 stamp_sec_fraction;	/* fractional seconds of stamp_xtime */
109 	__u32 hrtimer_res;		/* hrtimer resolution */
110    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
111 };
112 
113 #endif /* CONFIG_PPC64 */
114 
115 extern struct vdso_data *vdso_data;
116 
117 #else /* __ASSEMBLY__ */
118 
119 .macro get_datapage ptr, tmp
120 	bcl	20, 31, .+4
121 	mflr	\ptr
122 	addi	\ptr, \ptr, (__kernel_datapage_offset - (.-4))@l
123 	lwz	\tmp, 0(\ptr)
124 	add	\ptr, \tmp, \ptr
125 .endm
126 
127 #endif /* __ASSEMBLY__ */
128 
129 #endif /* __KERNEL__ */
130 #endif /* _SYSTEMCFG_H */
131