system.c
/*
* system.c - a driver for reserving pnp system resources
*
* Some code is based on pnpbios_core.c
* Copyright 2002 Adam Belay <ambx1@neo.rr.com>
* (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
* Bjorn Helgaas <bjorn.helgaas@hp.com>
*/
#include <linux/pnp.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/ioport.h>
static const struct pnp_device_id pnp_dev_table[] = {
/* General ID for reserving resources */
{ "PNP0c02", 0 },
/* memory controller */
{ "PNP0c01", 0 },
{ "", 0 }
};
static void reserve_range(char *pnpid, int start, int end, int port)
{
struct resource *res;
char *regionid;
regionid = kmalloc(16, GFP_KERNEL);
if (regionid == NULL)
return;
snprintf(regionid, 16, "pnp %s", pnpid);
if (port)
res = request_region(start,end-start+1,regionid);
else
res = request_mem_region(start,end-start+1,regionid);
if (res == NULL)
kfree(regionid);
else
res->flags &= ~IORESOURCE_BUSY;
/*
* Failures at this point are usually harmless. pci quirks for
* example do reserve stuff they know about too, so we may well
* have double reservations.
*/
printk(KERN_INFO
"pnp: %s: %s range 0x%x-0x%x %s reserved\n",
pnpid, port ? "ioport" : "iomem", start, end,
NULL != res ? "has been" : "could not be");
}
static void reserve_resources_of_dev(struct pnp_dev *dev)
{
int i;
for (i = 0; i < PNP_MAX_PORT; i++) {
if (!pnp_port_valid(dev, i))
continue;
if (pnp_port_start(dev, i) == 0)
continue; /* disabled */
if (pnp_port_start(dev, i) < 0x100)
/*
* Below 0x100 is only standard PC hardware
* (pics, kbd, timer, dma, ...)
* We should not get resource conflicts there,
* and the kernel reserves these anyway
* (see arch/i386/kernel/setup.c).
* So, do nothing
*/
continue;
if (pnp_port_end(dev, i) < pnp_port_start(dev, i))
continue; /* invalid */
reserve_range(dev->dev.bus_id, pnp_port_start(dev, i),
pnp_port_end(dev, i), 1);
}
for (i = 0; i < PNP_MAX_MEM; i++) {
if (!pnp_mem_valid(dev, i))
continue;
reserve_range(dev->dev.bus_id, pnp_mem_start(dev, i),
pnp_mem_end(dev, i), 0);
}
return;
}
static int system_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id *dev_id)
{
reserve_resources_of_dev(dev);
return 0;
}
static struct pnp_driver system_pnp_driver = {
.name = "system",
.id_table = pnp_dev_table,
.flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
.probe = system_pnp_probe,
.remove = NULL,
};
static int __init pnp_system_init(void)
{
return pnp_register_driver(&system_pnp_driver);
}
/**
* Reserve motherboard resources after PCI claim BARs,
* but before PCI assign resources for uninitialized PCI devices
*/
fs_initcall(pnp_system_init);