drivers/nubus/proc.c

   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 }