xref: /linux/drivers/nubus/proc.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
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 
36 static int
37 nubus_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 
48 static struct proc_dir_entry *proc_bus_nubus_dir;
49 
50 /*
51  * /proc/bus/nubus/x/ stuff
52  */
53 
54 struct proc_dir_entry *nubus_proc_add_board(struct nubus_board *board)
55 {
56 	char name[2];
57 
58 	if (!proc_bus_nubus_dir || !nubus_populate_procfs)
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 
68 struct 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 || !nubus_populate_procfs)
76 		return NULL;
77 	snprintf(name, sizeof(name), "%x", ent->type);
78 	remove_proc_subtree(name, procdir);
79 	return proc_mkdir_data(name, 0555, procdir, (void *)lanes);
80 }
81 
82 /* The PDE private data for a file under /proc/bus/nubus/x/ is a pointer to
83  * an instance of the following structure, which gives the location and size
84  * of the resource data in the slot ROM. For slot resources which hold only a
85  * small integer, this integer value is stored directly and size is set to 0.
86  * A NULL private data pointer indicates an unrecognized resource.
87  */
88 
89 struct nubus_proc_pde_data {
90 	unsigned char *res_ptr;
91 	unsigned int res_size;
92 };
93 
94 static struct nubus_proc_pde_data *
95 nubus_proc_alloc_pde_data(unsigned char *ptr, unsigned int size)
96 {
97 	struct nubus_proc_pde_data *pded;
98 
99 	pded = kmalloc(sizeof(*pded), GFP_KERNEL);
100 	if (!pded)
101 		return NULL;
102 
103 	pded->res_ptr = ptr;
104 	pded->res_size = size;
105 	return pded;
106 }
107 
108 static int nubus_proc_rsrc_show(struct seq_file *m, void *v)
109 {
110 	struct inode *inode = m->private;
111 	struct nubus_proc_pde_data *pded;
112 
113 	pded = pde_data(inode);
114 	if (!pded)
115 		return 0;
116 
117 	if (pded->res_size > m->size)
118 		return -EFBIG;
119 
120 	if (pded->res_size) {
121 		int lanes = (int)proc_get_parent_data(inode);
122 		struct nubus_dirent ent;
123 
124 		if (!lanes)
125 			return 0;
126 
127 		ent.mask = lanes;
128 		ent.base = pded->res_ptr;
129 		ent.data = 0;
130 		nubus_seq_write_rsrc_mem(m, &ent, pded->res_size);
131 	} else {
132 		unsigned int data = (unsigned int)pded->res_ptr;
133 
134 		seq_putc(m, data >> 16);
135 		seq_putc(m, data >> 8);
136 		seq_putc(m, data >> 0);
137 	}
138 	return 0;
139 }
140 
141 static int nubus_rsrc_proc_open(struct inode *inode, struct file *file)
142 {
143 	return single_open(file, nubus_proc_rsrc_show, inode);
144 }
145 
146 static const struct proc_ops nubus_rsrc_proc_ops = {
147 	.proc_open	= nubus_rsrc_proc_open,
148 	.proc_read	= seq_read,
149 	.proc_lseek	= seq_lseek,
150 	.proc_release	= single_release,
151 };
152 
153 void nubus_proc_add_rsrc_mem(struct proc_dir_entry *procdir,
154 			     const struct nubus_dirent *ent,
155 			     unsigned int size)
156 {
157 	char name[9];
158 	struct nubus_proc_pde_data *pded;
159 
160 	if (!procdir || !nubus_populate_procfs)
161 		return;
162 
163 	snprintf(name, sizeof(name), "%x", ent->type);
164 	if (size)
165 		pded = nubus_proc_alloc_pde_data(nubus_dirptr(ent), size);
166 	else
167 		pded = NULL;
168 	remove_proc_subtree(name, procdir);
169 	proc_create_data(name, S_IFREG | 0444, procdir,
170 			 &nubus_rsrc_proc_ops, pded);
171 }
172 
173 void nubus_proc_add_rsrc(struct proc_dir_entry *procdir,
174 			 const struct nubus_dirent *ent)
175 {
176 	char name[9];
177 	unsigned char *data = (unsigned char *)ent->data;
178 
179 	if (!procdir || !nubus_populate_procfs)
180 		return;
181 
182 	snprintf(name, sizeof(name), "%x", ent->type);
183 	remove_proc_subtree(name, procdir);
184 	proc_create_data(name, S_IFREG | 0444, procdir,
185 			 &nubus_rsrc_proc_ops,
186 			 nubus_proc_alloc_pde_data(data, 0));
187 }
188 
189 /*
190  * /proc/nubus stuff
191  */
192 
193 void __init nubus_proc_init(void)
194 {
195 	proc_create_single("nubus", 0, NULL, nubus_proc_show);
196 	proc_bus_nubus_dir = proc_mkdir("bus/nubus", NULL);
197 	if (!proc_bus_nubus_dir)
198 		return;
199 	proc_create_single("devices", 0, proc_bus_nubus_dir,
200 			nubus_devices_proc_show);
201 }
202