drivers/nubus/proc.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /* drivers/nubus/proc.c: Proc FS interface for NuBus.
0003
0004    By David Huggins-Daines <dhd@debian.org>
0005
0006    Much code and many ideas from drivers/pci/proc.c:
0007    Copyright (c) 1997, 1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
0008
0009    This is initially based on the Zorro and PCI interfaces.  However,
0010    it works somewhat differently.  The intent is to provide a
0011    structure in /proc analogous to the structure of the NuBus ROM
0012    resources.
0013
0014    Therefore each board function gets a directory, which may in turn
0015    contain subdirectories.  Each slot resource is a file.  Unrecognized
0016    resources are empty files, since every resource ID requires a special
0017    case (e.g. if the resource ID implies a directory or block, then its
0018    value has to be interpreted as a slot ROM pointer etc.).
0019  */
0020
0021 #include <linux/types.h>
0022 #include <linux/kernel.h>
0023 #include <linux/nubus.h>
0024 #include <linux/proc_fs.h>
0025 #include <linux/seq_file.h>
0026 #include <linux/slab.h>
0027 #include <linux/init.h>
0028 #include <linux/module.h>
0029 #include <linux/uaccess.h>
0030 #include <asm/byteorder.h>
0031
0032 /*
0033  * /proc/bus/nubus/devices stuff
0034  */
0035
0036 static int
0037 nubus_devices_proc_show(struct seq_file *m, void *v)
0038 {
0039     struct nubus_rsrc *fres;
0040
0041     for_each_func_rsrc(fres)
0042         seq_printf(m, "%x\t%04x %04x %04x %04x\t%08lx\n",
0043                fres->board->slot, fres->category, fres->type,
0044                fres->dr_sw, fres->dr_hw, fres->board->slot_addr);
0045     return 0;
0046 }
0047
0048 static struct proc_dir_entry *proc_bus_nubus_dir;
0049
0050 /*
0051  * /proc/bus/nubus/x/ stuff
0052  */
0053
0054 struct proc_dir_entry *nubus_proc_add_board(struct nubus_board *board)
0055 {
0056     char name[2];
0057
0058     if (!proc_bus_nubus_dir)
0059         return NULL;
0060     snprintf(name, sizeof(name), "%x", board->slot);
0061     return proc_mkdir(name, proc_bus_nubus_dir);
0062 }
0063
0064 /* The PDE private data for any directory under /proc/bus/nubus/x/
0065  * is the bytelanes value for the board in slot x.
0066  */
0067
0068 struct proc_dir_entry *nubus_proc_add_rsrc_dir(struct proc_dir_entry *procdir,
0069                            const struct nubus_dirent *ent,
0070                            struct nubus_board *board)
0071 {
0072     char name[9];
0073     int lanes = board->lanes;
0074
0075     if (!procdir)
0076         return NULL;
0077     snprintf(name, sizeof(name), "%x", ent->type);
0078     return proc_mkdir_data(name, 0555, procdir, (void *)lanes);
0079 }
0080
0081 /* The PDE private data for a file under /proc/bus/nubus/x/ is a pointer to
0082  * an instance of the following structure, which gives the location and size
0083  * of the resource data in the slot ROM. For slot resources which hold only a
0084  * small integer, this integer value is stored directly and size is set to 0.
0085  * A NULL private data pointer indicates an unrecognized resource.
0086  */
0087
0088 struct nubus_proc_pde_data {
0089     unsigned char *res_ptr;
0090     unsigned int res_size;
0091 };
0092
0093 static struct nubus_proc_pde_data *
0094 nubus_proc_alloc_pde_data(unsigned char *ptr, unsigned int size)
0095 {
0096     struct nubus_proc_pde_data *pded;
0097
0098     pded = kmalloc(sizeof(*pded), GFP_KERNEL);
0099     if (!pded)
0100         return NULL;
0101
0102     pded->res_ptr = ptr;
0103     pded->res_size = size;
0104     return pded;
0105 }
0106
0107 static int nubus_proc_rsrc_show(struct seq_file *m, void *v)
0108 {
0109     struct inode *inode = m->private;
0110     struct nubus_proc_pde_data *pded;
0111
0112     pded = pde_data(inode);
0113     if (!pded)
0114         return 0;
0115
0116     if (pded->res_size > m->size)
0117         return -EFBIG;
0118
0119     if (pded->res_size) {
0120         int lanes = (int)proc_get_parent_data(inode);
0121         struct nubus_dirent ent;
0122
0123         if (!lanes)
0124             return 0;
0125
0126         ent.mask = lanes;
0127         ent.base = pded->res_ptr;
0128         ent.data = 0;
0129         nubus_seq_write_rsrc_mem(m, &ent, pded->res_size);
0130     } else {
0131         unsigned int data = (unsigned int)pded->res_ptr;
0132
0133         seq_putc(m, data >> 16);
0134         seq_putc(m, data >> 8);
0135         seq_putc(m, data >> 0);
0136     }
0137     return 0;
0138 }
0139
0140 void nubus_proc_add_rsrc_mem(struct proc_dir_entry *procdir,
0141                  const struct nubus_dirent *ent,
0142                  unsigned int size)
0143 {
0144     char name[9];
0145     struct nubus_proc_pde_data *pded;
0146
0147     if (!procdir)
0148         return;
0149
0150     snprintf(name, sizeof(name), "%x", ent->type);
0151     if (size)
0152         pded = nubus_proc_alloc_pde_data(nubus_dirptr(ent), size);
0153     else
0154         pded = NULL;
0155     proc_create_single_data(name, S_IFREG | 0444, procdir,
0156             nubus_proc_rsrc_show, pded);
0157 }
0158
0159 void nubus_proc_add_rsrc(struct proc_dir_entry *procdir,
0160              const struct nubus_dirent *ent)
0161 {
0162     char name[9];
0163     unsigned char *data = (unsigned char *)ent->data;
0164
0165     if (!procdir)
0166         return;
0167
0168     snprintf(name, sizeof(name), "%x", ent->type);
0169     proc_create_single_data(name, S_IFREG | 0444, procdir,
0170             nubus_proc_rsrc_show,
0171             nubus_proc_alloc_pde_data(data, 0));
0172 }
0173
0174 /*
0175  * /proc/nubus stuff
0176  */
0177
0178 void __init nubus_proc_init(void)
0179 {
0180     proc_create_single("nubus", 0, NULL, nubus_proc_show);
0181     proc_bus_nubus_dir = proc_mkdir("bus/nubus", NULL);
0182     if (!proc_bus_nubus_dir)
0183         return;
0184     proc_create_single("devices", 0, proc_bus_nubus_dir,
0185             nubus_devices_proc_show);
0186 }