proc_powerpc.c

  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("/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);