arch/powerpc/include/asm/vdso_datapage.h

   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 #include <vdso/datapage.h>
  40
  41 #define SYSCALL_MAP_SIZE      ((NR_syscalls + 31) / 32)
  42
  43 /*
  44  * So here is the ppc64 backward compatible version
  45  */
  46
  47 #ifdef CONFIG_PPC64
  48
  49 struct vdso_arch_data {
  50         __u8  eye_catcher[16];          /* Eyecatcher: SYSTEMCFG:PPC64  0x00 */
  51         struct {                        /* Systemcfg version numbers         */
  52                 __u32 major;            /* Major number                 0x10 */
  53                 __u32 minor;            /* Minor number                 0x14 */
  54         } version;
  55
  56         /* Note about the platform flags: it now only contains the lpar
  57          * bit. The actual platform number is dead and buried
  58          */
  59         __u32 platform;                 /* Platform flags               0x18 */
  60         __u32 processor;                /* Processor type               0x1C */
  61         __u64 processorCount;           /* # of physical processors     0x20 */
  62         __u64 physicalMemorySize;       /* Size of real memory(B)       0x28 */
  63         __u64 tb_orig_stamp;            /* (NU) Timebase at boot        0x30 */
  64         __u64 tb_ticks_per_sec;         /* Timebase tics / sec          0x38 */
  65         __u64 tb_to_xs;                 /* (NU) Inverse of TB to 2^20   0x40 */
  66         __u64 stamp_xsec;               /* (NU)                         0x48 */
  67         __u64 tb_update_count;          /* (NU) Timebase atomicity ctr  0x50 */
  68         __u32 tz_minuteswest;           /* (NU) Min. west of Greenwich  0x58 */
  69         __u32 tz_dsttime;               /* (NU) Type of dst correction  0x5C */
  70         __u32 dcache_size;              /* L1 d-cache size              0x60 */
  71         __u32 dcache_line_size;         /* L1 d-cache line size         0x64 */
  72         __u32 icache_size;              /* L1 i-cache size              0x68 */
  73         __u32 icache_line_size;         /* L1 i-cache line size         0x6C */
  74
  75         /* those additional ones don't have to be located anywhere
  76          * special as they were not part of the original systemcfg
  77          */
  78         __u32 dcache_block_size;                /* L1 d-cache block size     */
  79         __u32 icache_block_size;                /* L1 i-cache block size     */
  80         __u32 dcache_log_block_size;            /* L1 d-cache log block size */
  81         __u32 icache_log_block_size;            /* L1 i-cache log block size */
  82         __u32 syscall_map[SYSCALL_MAP_SIZE];    /* Map of syscalls  */
  83         __u32 compat_syscall_map[SYSCALL_MAP_SIZE];     /* Map of compat syscalls */
  84
  85         struct vdso_data data[CS_BASES];
  86 };
  87
  88 #else /* CONFIG_PPC64 */
  89
  90 /*
  91  * And here is the simpler 32 bits version
  92  */
  93 struct vdso_arch_data {
  94         __u64 tb_ticks_per_sec;         /* Timebase tics / sec          0x38 */
  95         __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
  96         __u32 compat_syscall_map[0];    /* No compat syscalls on PPC32 */
  97         struct vdso_data data[CS_BASES];
  98 };
  99
 100 #endif /* CONFIG_PPC64 */
 101
 102 extern struct vdso_arch_data *vdso_data;
 103
 104 #else /* __ASSEMBLY__ */
 105
 106 .macro get_datapage ptr
 107         bcl     20, 31, .+4
 108 999:
 109         mflr    \ptr
 110 #if CONFIG_PPC_PAGE_SHIFT > 14
 111         addis   \ptr, \ptr, (_vdso_datapage - 999b)@ha
 112 #endif
 113         addi    \ptr, \ptr, (_vdso_datapage - 999b)@l
 114 .endm
 115
 116 #endif /* __ASSEMBLY__ */
 117
 118 #endif /* __KERNEL__ */
 119 #endif /* _SYSTEMCFG_H */