xref: /linux/arch/powerpc/kernel/proc_powerpc.c (revision fcc79e1714e8c2b8e216dc3149812edd37884eef)
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 
13 #include <asm/machdep.h>
14 #include <asm/vdso_datapage.h>
15 #include <asm/rtas.h>
16 #include <asm/systemcfg.h>
17 #include <linux/uaccess.h>
18 
19 #ifdef CONFIG_PPC64_PROC_SYSTEMCFG
20 
21 static loff_t page_map_seek(struct file *file, loff_t off, int whence)
22 {
23 	return fixed_size_llseek(file, off, whence, PAGE_SIZE);
24 }
25 
26 static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes,
27 			      loff_t *ppos)
28 {
29 	return simple_read_from_buffer(buf, nbytes, ppos,
30 			pde_data(file_inode(file)), PAGE_SIZE);
31 }
32 
33 static int page_map_mmap( struct file *file, struct vm_area_struct *vma )
34 {
35 	if ((vma->vm_end - vma->vm_start) > PAGE_SIZE)
36 		return -EINVAL;
37 
38 	return remap_pfn_range(vma, vma->vm_start,
39 			       __pa(pde_data(file_inode(file))) >> PAGE_SHIFT,
40 			       PAGE_SIZE, vma->vm_page_prot);
41 }
42 
43 static const struct proc_ops page_map_proc_ops = {
44 	.proc_lseek	= page_map_seek,
45 	.proc_read	= page_map_read,
46 	.proc_mmap	= page_map_mmap,
47 };
48 
49 static union {
50 	struct systemcfg	data;
51 	u8			page[PAGE_SIZE];
52 } systemcfg_data_store __page_aligned_data;
53 struct systemcfg *systemcfg = &systemcfg_data_store.data;
54 
55 static int __init proc_ppc64_init(void)
56 {
57 	struct proc_dir_entry *pde;
58 
59 	strcpy((char *)systemcfg->eye_catcher, "SYSTEMCFG:PPC64");
60 	systemcfg->version.major = SYSTEMCFG_MAJOR;
61 	systemcfg->version.minor = SYSTEMCFG_MINOR;
62 	systemcfg->processor = mfspr(SPRN_PVR);
63 	/*
64 	 * Fake the old platform number for pSeries and add
65 	 * in LPAR bit if necessary
66 	 */
67 	systemcfg->platform = 0x100;
68 	if (firmware_has_feature(FW_FEATURE_LPAR))
69 		systemcfg->platform |= 1;
70 	systemcfg->physicalMemorySize = memblock_phys_mem_size();
71 	systemcfg->dcache_size = ppc64_caches.l1d.size;
72 	systemcfg->dcache_line_size = ppc64_caches.l1d.line_size;
73 	systemcfg->icache_size = ppc64_caches.l1i.size;
74 	systemcfg->icache_line_size = ppc64_caches.l1i.line_size;
75 
76 	pde = proc_create_data("powerpc/systemcfg", S_IFREG | 0444, NULL,
77 			       &page_map_proc_ops, systemcfg);
78 	if (!pde)
79 		return 1;
80 	proc_set_size(pde, PAGE_SIZE);
81 
82 	return 0;
83 }
84 __initcall(proc_ppc64_init);
85 
86 #endif /* CONFIG_PPC64_PROC_SYSTEMCFG */
87 
88 /*
89  * Create the ppc64 and ppc64/rtas directories early. This allows us to
90  * assume that they have been previously created in drivers.
91  */
92 static int __init proc_ppc64_create(void)
93 {
94 	struct proc_dir_entry *root;
95 
96 	root = proc_mkdir("powerpc", NULL);
97 	if (!root)
98 		return 1;
99 
100 #ifdef CONFIG_PPC64
101 	if (!proc_symlink("ppc64", NULL, "powerpc"))
102 		pr_err("Failed to create link /proc/ppc64 -> /proc/powerpc\n");
103 #endif
104 
105 	if (!of_find_node_by_path("/rtas"))
106 		return 0;
107 
108 	if (!proc_mkdir("rtas", root))
109 		return 1;
110 
111 	if (!proc_symlink("rtas", NULL, "powerpc/rtas"))
112 		return 1;
113 
114 	return 0;
115 }
116 core_initcall(proc_ppc64_create);
117