1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * system.c - a driver for reserving pnp system resources
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Some code is based on pnpbios_core.c
6*4882a593Smuzhiyun * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
7*4882a593Smuzhiyun * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
8*4882a593Smuzhiyun * Bjorn Helgaas <bjorn.helgaas@hp.com>
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include <linux/pnp.h>
12*4882a593Smuzhiyun #include <linux/device.h>
13*4882a593Smuzhiyun #include <linux/init.h>
14*4882a593Smuzhiyun #include <linux/slab.h>
15*4882a593Smuzhiyun #include <linux/kernel.h>
16*4882a593Smuzhiyun #include <linux/ioport.h>
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun static const struct pnp_device_id pnp_dev_table[] = {
19*4882a593Smuzhiyun /* General ID for reserving resources */
20*4882a593Smuzhiyun {"PNP0c02", 0},
21*4882a593Smuzhiyun /* memory controller */
22*4882a593Smuzhiyun {"PNP0c01", 0},
23*4882a593Smuzhiyun {"", 0}
24*4882a593Smuzhiyun };
25*4882a593Smuzhiyun
reserve_range(struct pnp_dev * dev,struct resource * r,int port)26*4882a593Smuzhiyun static void reserve_range(struct pnp_dev *dev, struct resource *r, int port)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun char *regionid;
29*4882a593Smuzhiyun const char *pnpid = dev_name(&dev->dev);
30*4882a593Smuzhiyun resource_size_t start = r->start, end = r->end;
31*4882a593Smuzhiyun struct resource *res;
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun regionid = kmalloc(16, GFP_KERNEL);
34*4882a593Smuzhiyun if (!regionid)
35*4882a593Smuzhiyun return;
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun snprintf(regionid, 16, "pnp %s", pnpid);
38*4882a593Smuzhiyun if (port)
39*4882a593Smuzhiyun res = request_region(start, end - start + 1, regionid);
40*4882a593Smuzhiyun else
41*4882a593Smuzhiyun res = request_mem_region(start, end - start + 1, regionid);
42*4882a593Smuzhiyun if (res)
43*4882a593Smuzhiyun res->flags &= ~IORESOURCE_BUSY;
44*4882a593Smuzhiyun else
45*4882a593Smuzhiyun kfree(regionid);
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun /*
48*4882a593Smuzhiyun * Failures at this point are usually harmless. pci quirks for
49*4882a593Smuzhiyun * example do reserve stuff they know about too, so we may well
50*4882a593Smuzhiyun * have double reservations.
51*4882a593Smuzhiyun */
52*4882a593Smuzhiyun dev_info(&dev->dev, "%pR %s reserved\n", r,
53*4882a593Smuzhiyun res ? "has been" : "could not be");
54*4882a593Smuzhiyun }
55*4882a593Smuzhiyun
reserve_resources_of_dev(struct pnp_dev * dev)56*4882a593Smuzhiyun static void reserve_resources_of_dev(struct pnp_dev *dev)
57*4882a593Smuzhiyun {
58*4882a593Smuzhiyun struct resource *res;
59*4882a593Smuzhiyun int i;
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_IO, i)); i++) {
62*4882a593Smuzhiyun if (res->flags & IORESOURCE_DISABLED)
63*4882a593Smuzhiyun continue;
64*4882a593Smuzhiyun if (res->start == 0)
65*4882a593Smuzhiyun continue; /* disabled */
66*4882a593Smuzhiyun if (res->start < 0x100)
67*4882a593Smuzhiyun /*
68*4882a593Smuzhiyun * Below 0x100 is only standard PC hardware
69*4882a593Smuzhiyun * (pics, kbd, timer, dma, ...)
70*4882a593Smuzhiyun * We should not get resource conflicts there,
71*4882a593Smuzhiyun * and the kernel reserves these anyway
72*4882a593Smuzhiyun * (see arch/i386/kernel/setup.c).
73*4882a593Smuzhiyun * So, do nothing
74*4882a593Smuzhiyun */
75*4882a593Smuzhiyun continue;
76*4882a593Smuzhiyun if (res->end < res->start)
77*4882a593Smuzhiyun continue; /* invalid */
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun reserve_range(dev, res, 1);
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
83*4882a593Smuzhiyun if (res->flags & IORESOURCE_DISABLED)
84*4882a593Smuzhiyun continue;
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun reserve_range(dev, res, 0);
87*4882a593Smuzhiyun }
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun
system_pnp_probe(struct pnp_dev * dev,const struct pnp_device_id * dev_id)90*4882a593Smuzhiyun static int system_pnp_probe(struct pnp_dev *dev,
91*4882a593Smuzhiyun const struct pnp_device_id *dev_id)
92*4882a593Smuzhiyun {
93*4882a593Smuzhiyun reserve_resources_of_dev(dev);
94*4882a593Smuzhiyun return 0;
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun static struct pnp_driver system_pnp_driver = {
98*4882a593Smuzhiyun .name = "system",
99*4882a593Smuzhiyun .id_table = pnp_dev_table,
100*4882a593Smuzhiyun .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
101*4882a593Smuzhiyun .probe = system_pnp_probe,
102*4882a593Smuzhiyun };
103*4882a593Smuzhiyun
pnp_system_init(void)104*4882a593Smuzhiyun static int __init pnp_system_init(void)
105*4882a593Smuzhiyun {
106*4882a593Smuzhiyun return pnp_register_driver(&system_pnp_driver);
107*4882a593Smuzhiyun }
108*4882a593Smuzhiyun
109*4882a593Smuzhiyun /**
110*4882a593Smuzhiyun * Reserve motherboard resources after PCI claim BARs,
111*4882a593Smuzhiyun * but before PCI assign resources for uninitialized PCI devices
112*4882a593Smuzhiyun */
113*4882a593Smuzhiyun fs_initcall(pnp_system_init);
114