tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
17static 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
25static void reserve_range(char *pnpid, int start, int end, int port)
26{
27 struct resource *res;
28 char *regionid;
29
30 regionid = kmalloc(16, GFP_KERNEL);
31 if (regionid == NULL)
32 return;
33 snprintf(regionid, 16, "pnp %s", pnpid);
34 if (port)
35 res = request_region(start,end-start+1,regionid);
36 else
37 res = request_mem_region(start,end-start+1,regionid);
38 if (res == NULL)
39 kfree(regionid);
40 else
41 res->flags &= ~IORESOURCE_BUSY;
42 /*
43 * Failures at this point are usually harmless. pci quirks for
44 * example do reserve stuff they know about too, so we may well
45 * have double reservations.
46 */
47 printk(KERN_INFO
48 "pnp: %s: %s range 0x%x-0x%x %s reserved\n",
49 pnpid, port ? "ioport" : "iomem", start, end,
50 NULL != res ? "has been" : "could not be");
51}
52
53static void reserve_resources_of_dev(struct pnp_dev *dev)
54{
55 int i;
56
57 for (i = 0; i < PNP_MAX_PORT; i++) {
58 if (!pnp_port_valid(dev, i))
59 continue;
60 if (pnp_port_start(dev, i) == 0)
61 continue; /* disabled */
62 if (pnp_port_start(dev, i) < 0x100)
63 /*
64 * Below 0x100 is only standard PC hardware
65 * (pics, kbd, timer, dma, ...)
66 * We should not get resource conflicts there,
67 * and the kernel reserves these anyway
68 * (see arch/i386/kernel/setup.c).
69 * So, do nothing
70 */
71 continue;
72 if (pnp_port_end(dev, i) < pnp_port_start(dev, i))
73 continue; /* invalid */
74
75 reserve_range(dev->dev.bus_id, pnp_port_start(dev, i),
76 pnp_port_end(dev, i), 1);
77 }
78
79 for (i = 0; i < PNP_MAX_MEM; i++) {
80 if (!pnp_mem_valid(dev, i))
81 continue;
82
83 reserve_range(dev->dev.bus_id, pnp_mem_start(dev, i),
84 pnp_mem_end(dev, i), 0);
85 }
86
87 return;
88}
89
90static int system_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id *dev_id)
91{
92 reserve_resources_of_dev(dev);
93 return 0;
94}
95
96static 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 .remove = NULL,
102};
103
104static int __init pnp_system_init(void)
105{
106 return pnp_register_driver(&system_pnp_driver);
107}
108
109/**
110 * Reserve motherboard resources after PCI claim BARs,
111 * but before PCI assign resources for uninitialized PCI devices
112 */
113fs_initcall(pnp_system_init);