1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen IBM Corporation
4 */
5
6#include <linux/init.h>
7#include <linux/memblock.h>
8#include <linux/mm.h>
9#include <linux/proc_fs.h>
10#include <linux/kernel.h>
11#include <linux/of.h>
12#include <linux/string.h>
13
14#include <asm/machdep.h>
15#include <asm/vdso_datapage.h>
16#include <asm/rtas.h>
17#include <asm/systemcfg.h>
18#include <linux/uaccess.h>
19
20#ifdef CONFIG_PPC64_PROC_SYSTEMCFG
21
22static loff_t page_map_seek(struct file *file, loff_t off, int whence)
23{
24 return fixed_size_llseek(file, off, whence, PAGE_SIZE);
25}
26
27static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes,
28 loff_t *ppos)
29{
30 return simple_read_from_buffer(buf, nbytes, ppos,
31 pde_data(file_inode(file)), PAGE_SIZE);
32}
33
34static int page_map_mmap( struct file *file, struct vm_area_struct *vma )
35{
36 if ((vma->vm_end - vma->vm_start) > PAGE_SIZE)
37 return -EINVAL;
38
39 return remap_pfn_range(vma, vma->vm_start,
40 __pa(pde_data(file_inode(file))) >> PAGE_SHIFT,
41 PAGE_SIZE, vma->vm_page_prot);
42}
43
44static const struct proc_ops page_map_proc_ops = {
45 .proc_lseek = page_map_seek,
46 .proc_read = page_map_read,
47 .proc_mmap = page_map_mmap,
48};
49
50static union {
51 struct systemcfg data;
52 u8 page[PAGE_SIZE];
53} systemcfg_data_store __page_aligned_data;
54struct systemcfg *systemcfg = &systemcfg_data_store.data;
55
56static int __init proc_ppc64_init(void)
57{
58 struct proc_dir_entry *pde;
59
60 strscpy(systemcfg->eye_catcher, "SYSTEMCFG:PPC64");
61 systemcfg->version.major = SYSTEMCFG_MAJOR;
62 systemcfg->version.minor = SYSTEMCFG_MINOR;
63 systemcfg->processor = mfspr(SPRN_PVR);
64 /*
65 * Fake the old platform number for pSeries and add
66 * in LPAR bit if necessary
67 */
68 systemcfg->platform = 0x100;
69 if (firmware_has_feature(FW_FEATURE_LPAR))
70 systemcfg->platform |= 1;
71 systemcfg->physicalMemorySize = memblock_phys_mem_size();
72 systemcfg->dcache_size = ppc64_caches.l1d.size;
73 systemcfg->dcache_line_size = ppc64_caches.l1d.line_size;
74 systemcfg->icache_size = ppc64_caches.l1i.size;
75 systemcfg->icache_line_size = ppc64_caches.l1i.line_size;
76
77 pde = proc_create_data("powerpc/systemcfg", S_IFREG | 0444, NULL,
78 &page_map_proc_ops, systemcfg);
79 if (!pde)
80 return 1;
81 proc_set_size(pde, PAGE_SIZE);
82
83 return 0;
84}
85__initcall(proc_ppc64_init);
86
87#endif /* CONFIG_PPC64_PROC_SYSTEMCFG */
88
89/*
90 * Create the ppc64 and ppc64/rtas directories early. This allows us to
91 * assume that they have been previously created in drivers.
92 */
93static int __init proc_ppc64_create(void)
94{
95 struct proc_dir_entry *root;
96
97 root = proc_mkdir("powerpc", NULL);
98 if (!root)
99 return 1;
100
101#ifdef CONFIG_PPC64
102 if (!proc_symlink("ppc64", NULL, "powerpc"))
103 pr_err("Failed to create link /proc/ppc64 -> /proc/powerpc\n");
104#endif
105
106 if (!of_find_node_by_path(path: "/rtas"))
107 return 0;
108
109 if (!proc_mkdir("rtas", root))
110 return 1;
111
112 if (!proc_symlink("rtas", NULL, "powerpc/rtas"))
113 return 1;
114
115 return 0;
116}
117core_initcall(proc_ppc64_create);
118

source code of linux/arch/powerpc/kernel/proc_powerpc.c