[linux.git] / drivers / pnp / system.c

// SPDX-License-Identifier: GPL-2.0
/*
 * system.c - a driver for reserving pnp system resources
 *
 * Some code is based on pnpbios_core.c
 * Copyright 2002 Adam Belay <[email protected]>
 * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
 *	Bjorn Helgaas <[email protected]>
 */

#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(struct pnp_dev *dev, struct resource *r, int port)
{
	char *regionid;
	const char *pnpid = dev_name(&dev->dev);
	resource_size_t start = r->start, end = r->end;
	struct resource *res;

	regionid = kmalloc(16, GFP_KERNEL);
	if (!regionid)
		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)
		res->flags &= ~IORESOURCE_BUSY;
	else
		kfree(regionid);

	/*
	 * 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.
	 */
	dev_info(&dev->dev, "%pR %s reserved\n", r,
		 res ? "has been" : "could not be");
}

static void reserve_resources_of_dev(struct pnp_dev *dev)
{
	struct resource *res;
	int i;

	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_IO, i)); i++) {
		if (res->flags & IORESOURCE_DISABLED)
			continue;
		if (res->start == 0)
			continue;	/* disabled */
		if (res->start < 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 (res->end < res->start)
			continue;	/* invalid */

		reserve_range(dev, res, 1);
	}

	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
		if (res->flags & IORESOURCE_DISABLED)
			continue;

		reserve_range(dev, res, 0);
	}
}

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,
};

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);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* system.c - a driver for reserving pnp system resources
	4	*
	5	* Some code is based on pnpbios_core.c
	6	* Copyright 2002 Adam Belay <[email protected]>
a8c78f7f BH	7	* (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
a8c78f7f BH	8	* Bjorn Helgaas <[email protected]>
1da177e4 LT	9	*/
	10
	11	#include <linux/pnp.h>
	12	#include <linux/device.h>
	13	#include <linux/init.h>
	14	#include <linux/slab.h>
	15	#include <linux/kernel.h>
	16	#include <linux/ioport.h>
	17
	18	static const struct pnp_device_id pnp_dev_table[] = {
	19	/* General ID for reserving resources */
9dd78466	20	{"PNP0c02", 0},
1da177e4	21	/* memory controller */
9dd78466 BH	22	{"PNP0c01", 0},
9dd78466 BH	23	{"", 0}
1da177e4 LT	24	};
1da177e4 LT	25
9a007b37	26	static void reserve_range(struct pnp_dev dev, struct resource r, int port)
1da177e4	27	{
1da177e4	28	char *regionid;
c85e37c5	29	const char *pnpid = dev_name(&dev->dev);
9a007b37	30	resource_size_t start = r->start, end = r->end;
0294112e	31	struct resource *res;
1da177e4 LT	32
1da177e4 LT	33	regionid = kmalloc(16, GFP_KERNEL);
b933e19d	34	if (!regionid)
1da177e4	35	return;
b933e19d	36
1da177e4	37	snprintf(regionid, 16, "pnp %s", pnpid);
0294112e RW	38	if (port)
	39	res = request_region(start, end - start + 1, regionid);
	40	else
	41	res = request_mem_region(start, end - start + 1, regionid);
	42	if (res)
	43	res->flags &= ~IORESOURCE_BUSY;
	44	else
b933e19d BH	45	kfree(regionid);
b933e19d BH	46
1da177e4 LT	47	/*
	48	* Failures at this point are usually harmless. pci quirks for
	49	* example do reserve stuff they know about too, so we may well
	50	* have double reservations.
	51	*/
c7dabef8	52	dev_info(&dev->dev, "%pR %s reserved\n", r,
0294112e	53	res ? "has been" : "could not be");
1da177e4 LT	54	}
1da177e4 LT	55
b933e19d	56	static void reserve_resources_of_dev(struct pnp_dev *dev)
1da177e4	57	{
95ab3669	58	struct resource *res;
1da177e4 LT	59	int i;
1da177e4 LT	60
95ab3669	61	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_IO, i)); i++) {
aee3ad81	62	if (res->flags & IORESOURCE_DISABLED)
1da177e4	63	continue;
95ab3669	64	if (res->start == 0)
5859554c	65	continue; /* disabled */
95ab3669	66	if (res->start < 0x100)
1da177e4 LT	67	/*
	68	* Below 0x100 is only standard PC hardware
	69	* (pics, kbd, timer, dma, ...)
	70	* We should not get resource conflicts there,
	71	* and the kernel reserves these anyway
	72	* (see arch/i386/kernel/setup.c).
	73	* So, do nothing
	74	*/
	75	continue;
95ab3669	76	if (res->end < res->start)
5859554c BH	77	continue; /* invalid */
5859554c BH	78
9a007b37	79	reserve_range(dev, res, 1);
1da177e4 LT	80	}
1da177e4 LT	81
95ab3669	82	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
aee3ad81	83	if (res->flags & IORESOURCE_DISABLED)
a8c78f7f BH	84	continue;
a8c78f7f BH	85
9a007b37	86	reserve_range(dev, res, 0);
a8c78f7f	87	}
1da177e4 LT	88	}
1da177e4 LT	89
9dd78466 BH	90	static int system_pnp_probe(struct pnp_dev *dev,
9dd78466 BH	91	const struct pnp_device_id *dev_id)
1da177e4 LT	92	{
	93	reserve_resources_of_dev(dev);
	94	return 0;
	95	}
	96
	97	static struct pnp_driver system_pnp_driver = {
07d4e9af	98	.name = "system",
9dd78466	99	.id_table = pnp_dev_table,
07d4e9af BH	100	.flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
07d4e9af BH	101	.probe = system_pnp_probe,
1da177e4 LT	102	};
	103
	104	static 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	*/
	113	fs_initcall(pnp_system_init);