xref: /kernel/linux/linux-5.10/drivers/nubus/proc.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/* drivers/nubus/proc.c: Proc FS interface for NuBus.
3
4   By David Huggins-Daines <dhd@debian.org>
5
6   Much code and many ideas from drivers/pci/proc.c:
7   Copyright (c) 1997, 1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
8
9   This is initially based on the Zorro and PCI interfaces.  However,
10   it works somewhat differently.  The intent is to provide a
11   structure in /proc analogous to the structure of the NuBus ROM
12   resources.
13
14   Therefore each board function gets a directory, which may in turn
15   contain subdirectories.  Each slot resource is a file.  Unrecognized
16   resources are empty files, since every resource ID requires a special
17   case (e.g. if the resource ID implies a directory or block, then its
18   value has to be interpreted as a slot ROM pointer etc.).
19 */
20
21#include <linux/types.h>
22#include <linux/kernel.h>
23#include <linux/nubus.h>
24#include <linux/proc_fs.h>
25#include <linux/seq_file.h>
26#include <linux/slab.h>
27#include <linux/init.h>
28#include <linux/module.h>
29#include <linux/uaccess.h>
30#include <asm/byteorder.h>
31
32/*
33 * /proc/bus/nubus/devices stuff
34 */
35
36static int
37nubus_devices_proc_show(struct seq_file *m, void *v)
38{
39	struct nubus_rsrc *fres;
40
41	for_each_func_rsrc(fres)
42		seq_printf(m, "%x\t%04x %04x %04x %04x\t%08lx\n",
43			   fres->board->slot, fres->category, fres->type,
44			   fres->dr_sw, fres->dr_hw, fres->board->slot_addr);
45	return 0;
46}
47
48static struct proc_dir_entry *proc_bus_nubus_dir;
49
50/*
51 * /proc/bus/nubus/x/ stuff
52 */
53
54struct proc_dir_entry *nubus_proc_add_board(struct nubus_board *board)
55{
56	char name[2];
57
58	if (!proc_bus_nubus_dir)
59		return NULL;
60	snprintf(name, sizeof(name), "%x", board->slot);
61	return proc_mkdir(name, proc_bus_nubus_dir);
62}
63
64/* The PDE private data for any directory under /proc/bus/nubus/x/
65 * is the bytelanes value for the board in slot x.
66 */
67
68struct proc_dir_entry *nubus_proc_add_rsrc_dir(struct proc_dir_entry *procdir,
69					       const struct nubus_dirent *ent,
70					       struct nubus_board *board)
71{
72	char name[9];
73	int lanes = board->lanes;
74
75	if (!procdir)
76		return NULL;
77	snprintf(name, sizeof(name), "%x", ent->type);
78	return proc_mkdir_data(name, 0555, procdir, (void *)lanes);
79}
80
81/* The PDE private data for a file under /proc/bus/nubus/x/ is a pointer to
82 * an instance of the following structure, which gives the location and size
83 * of the resource data in the slot ROM. For slot resources which hold only a
84 * small integer, this integer value is stored directly and size is set to 0.
85 * A NULL private data pointer indicates an unrecognized resource.
86 */
87
88struct nubus_proc_pde_data {
89	unsigned char *res_ptr;
90	unsigned int res_size;
91};
92
93static struct nubus_proc_pde_data *
94nubus_proc_alloc_pde_data(unsigned char *ptr, unsigned int size)
95{
96	struct nubus_proc_pde_data *pde_data;
97
98	pde_data = kmalloc(sizeof(*pde_data), GFP_KERNEL);
99	if (!pde_data)
100		return NULL;
101
102	pde_data->res_ptr = ptr;
103	pde_data->res_size = size;
104	return pde_data;
105}
106
107static int nubus_proc_rsrc_show(struct seq_file *m, void *v)
108{
109	struct inode *inode = m->private;
110	struct nubus_proc_pde_data *pde_data;
111
112	pde_data = PDE_DATA(inode);
113	if (!pde_data)
114		return 0;
115
116	if (pde_data->res_size > m->size)
117		return -EFBIG;
118
119	if (pde_data->res_size) {
120		int lanes = (int)proc_get_parent_data(inode);
121		struct nubus_dirent ent;
122
123		if (!lanes)
124			return 0;
125
126		ent.mask = lanes;
127		ent.base = pde_data->res_ptr;
128		ent.data = 0;
129		nubus_seq_write_rsrc_mem(m, &ent, pde_data->res_size);
130	} else {
131		unsigned int data = (unsigned int)pde_data->res_ptr;
132
133		seq_putc(m, data >> 16);
134		seq_putc(m, data >> 8);
135		seq_putc(m, data >> 0);
136	}
137	return 0;
138}
139
140static int nubus_rsrc_proc_open(struct inode *inode, struct file *file)
141{
142	return single_open(file, nubus_proc_rsrc_show, inode);
143}
144
145static const struct proc_ops nubus_rsrc_proc_ops = {
146	.proc_open	= nubus_rsrc_proc_open,
147	.proc_read	= seq_read,
148	.proc_lseek	= seq_lseek,
149	.proc_release	= single_release,
150};
151
152void nubus_proc_add_rsrc_mem(struct proc_dir_entry *procdir,
153			     const struct nubus_dirent *ent,
154			     unsigned int size)
155{
156	char name[9];
157	struct nubus_proc_pde_data *pde_data;
158
159	if (!procdir)
160		return;
161
162	snprintf(name, sizeof(name), "%x", ent->type);
163	if (size)
164		pde_data = nubus_proc_alloc_pde_data(nubus_dirptr(ent), size);
165	else
166		pde_data = NULL;
167	proc_create_data(name, S_IFREG | 0444, procdir,
168			 &nubus_rsrc_proc_ops, pde_data);
169}
170
171void nubus_proc_add_rsrc(struct proc_dir_entry *procdir,
172			 const struct nubus_dirent *ent)
173{
174	char name[9];
175	unsigned char *data = (unsigned char *)ent->data;
176
177	if (!procdir)
178		return;
179
180	snprintf(name, sizeof(name), "%x", ent->type);
181	proc_create_data(name, S_IFREG | 0444, procdir,
182			 &nubus_rsrc_proc_ops,
183			 nubus_proc_alloc_pde_data(data, 0));
184}
185
186/*
187 * /proc/nubus stuff
188 */
189
190void __init nubus_proc_init(void)
191{
192	proc_create_single("nubus", 0, NULL, nubus_proc_show);
193	proc_bus_nubus_dir = proc_mkdir("bus/nubus", NULL);
194	if (!proc_bus_nubus_dir)
195		return;
196	proc_create_single("devices", 0, proc_bus_nubus_dir,
197			nubus_devices_proc_show);
198}
199