[S390] Remove obsolete recommendation for 8M ramdisk size.
[linux-2.6] / drivers / pnp / system.c
1 /*
2  * system.c - a driver for reserving pnp system resources
3  *
4  * Some code is based on pnpbios_core.c
5  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
6  * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
7  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
8  */
9
10 #include <linux/pnp.h>
11 #include <linux/device.h>
12 #include <linux/init.h>
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/ioport.h>
16
17 static const struct pnp_device_id pnp_dev_table[] = {
18         /* General ID for reserving resources */
19         {"PNP0c02", 0},
20         /* memory controller */
21         {"PNP0c01", 0},
22         {"", 0}
23 };
24
25 static void reserve_range(const char *pnpid, resource_size_t start,
26                           resource_size_t end, int port)
27 {
28         struct resource *res;
29         char *regionid;
30
31         regionid = kmalloc(16, GFP_KERNEL);
32         if (regionid == NULL)
33                 return;
34         snprintf(regionid, 16, "pnp %s", pnpid);
35         if (port)
36                 res = request_region(start, end - start + 1, regionid);
37         else
38                 res = request_mem_region(start, end - start + 1, regionid);
39         if (res == NULL)
40                 kfree(regionid);
41         else
42                 res->flags &= ~IORESOURCE_BUSY;
43         /*
44          * Failures at this point are usually harmless. pci quirks for
45          * example do reserve stuff they know about too, so we may well
46          * have double reservations.
47          */
48         printk(KERN_INFO "pnp: %s: %s range 0x%llx-0x%llx %s reserved\n",
49                pnpid, port ? "ioport" : "iomem",
50                (unsigned long long)start, (unsigned long long)end,
51                NULL != res ? "has been" : "could not be");
52 }
53
54 static void reserve_resources_of_dev(const struct pnp_dev *dev)
55 {
56         int i;
57
58         for (i = 0; i < PNP_MAX_PORT; i++) {
59                 if (!pnp_port_valid(dev, i))
60                         continue;
61                 if (pnp_port_start(dev, i) == 0)
62                         continue;       /* disabled */
63                 if (pnp_port_start(dev, i) < 0x100)
64                         /*
65                          * Below 0x100 is only standard PC hardware
66                          * (pics, kbd, timer, dma, ...)
67                          * We should not get resource conflicts there,
68                          * and the kernel reserves these anyway
69                          * (see arch/i386/kernel/setup.c).
70                          * So, do nothing
71                          */
72                         continue;
73                 if (pnp_port_end(dev, i) < pnp_port_start(dev, i))
74                         continue;       /* invalid */
75
76                 reserve_range(dev->dev.bus_id, pnp_port_start(dev, i),
77                               pnp_port_end(dev, i), 1);
78         }
79
80         for (i = 0; i < PNP_MAX_MEM; i++) {
81                 if (!pnp_mem_valid(dev, i))
82                         continue;
83
84                 reserve_range(dev->dev.bus_id, pnp_mem_start(dev, i),
85                               pnp_mem_end(dev, i), 0);
86         }
87 }
88
89 static int system_pnp_probe(struct pnp_dev *dev,
90                             const struct pnp_device_id *dev_id)
91 {
92         reserve_resources_of_dev(dev);
93         return 0;
94 }
95
96 static struct pnp_driver system_pnp_driver = {
97         .name     = "system",
98         .id_table = pnp_dev_table,
99         .flags    = PNP_DRIVER_RES_DO_NOT_CHANGE,
100         .probe    = system_pnp_probe,
101 };
102
103 static int __init pnp_system_init(void)
104 {
105         return pnp_register_driver(&system_pnp_driver);
106 }
107
108 /**
109  * Reserve motherboard resources after PCI claim BARs,
110  * but before PCI assign resources for uninitialized PCI devices
111  */
112 fs_initcall(pnp_system_init);