xref: /openbmc/linux/drivers/pnp/system.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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  *
7  */
8 
9 #include <linux/pnp.h>
10 #include <linux/device.h>
11 #include <linux/init.h>
12 #include <linux/slab.h>
13 #include <linux/kernel.h>
14 #include <linux/ioport.h>
15 
16 static const struct pnp_device_id pnp_dev_table[] = {
17 	/* General ID for reserving resources */
18 	{	"PNP0c02",		0	},
19 	/* memory controller */
20 	{	"PNP0c01",		0	},
21 	{	"",			0	}
22 };
23 
24 static void reserve_ioport_range(char *pnpid, int start, int end)
25 {
26 	struct resource *res;
27 	char *regionid;
28 
29 	regionid = kmalloc(16, GFP_KERNEL);
30 	if ( regionid == NULL )
31 		return;
32 	snprintf(regionid, 16, "pnp %s", pnpid);
33 	res = request_region(start,end-start+1,regionid);
34 	if ( res == NULL )
35 		kfree( regionid );
36 	else
37 		res->flags &= ~IORESOURCE_BUSY;
38 	/*
39 	 * Failures at this point are usually harmless. pci quirks for
40 	 * example do reserve stuff they know about too, so we may well
41 	 * have double reservations.
42 	 */
43 	printk(KERN_INFO
44 		"pnp: %s: ioport range 0x%x-0x%x %s reserved\n",
45 		pnpid, start, end,
46 		NULL != res ? "has been" : "could not be"
47 	);
48 
49 	return;
50 }
51 
52 static void reserve_resources_of_dev( struct pnp_dev *dev )
53 {
54 	int i;
55 
56 	for (i=0;i<PNP_MAX_PORT;i++) {
57 		if (!pnp_port_valid(dev, i))
58 			/* end of resources */
59 			continue;
60 		if (pnp_port_start(dev, i) == 0)
61 			/* disabled */
62 			/* Do nothing */
63 			continue;
64 		if (pnp_port_start(dev, i) < 0x100)
65 			/*
66 			 * Below 0x100 is only standard PC hardware
67 			 * (pics, kbd, timer, dma, ...)
68 			 * We should not get resource conflicts there,
69 			 * and the kernel reserves these anyway
70 			 * (see arch/i386/kernel/setup.c).
71 			 * So, do nothing
72 			 */
73 			continue;
74 		if (pnp_port_end(dev, i) < pnp_port_start(dev, i))
75 			/* invalid endpoint */
76 			/* Do nothing */
77 			continue;
78 		reserve_ioport_range(
79 			dev->dev.bus_id,
80 			pnp_port_start(dev, i),
81 			pnp_port_end(dev, i)
82 		);
83 	}
84 
85 	return;
86 }
87 
88 static int system_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id *dev_id)
89 {
90 	reserve_resources_of_dev(dev);
91 	return 0;
92 }
93 
94 static struct pnp_driver system_pnp_driver = {
95 	.name		= "system",
96 	.id_table	= pnp_dev_table,
97 	.flags		= PNP_DRIVER_RES_DO_NOT_CHANGE,
98 	.probe		= system_pnp_probe,
99 	.remove		= NULL,
100 };
101 
102 static int __init pnp_system_init(void)
103 {
104 	return pnp_register_driver(&system_pnp_driver);
105 }
106 
107 /**
108  * Reserve motherboard resources after PCI claim BARs,
109  * but before PCI assign resources for uninitialized PCI devices
110  */
111 fs_initcall(pnp_system_init);
112