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v6.8
  1// SPDX-License-Identifier: GPL-2.0
  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 <ambx1@neo.rr.com>
  7 * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
  8 *	Bjorn Helgaas <bjorn.helgaas@hp.com>
  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
 18static const struct pnp_device_id pnp_dev_table[] = {
 19	/* General ID for reserving resources */
 20	{"PNP0c02", 0},
 21	/* memory controller */
 22	{"PNP0c01", 0},
 23	{"", 0}
 24};
 25
 26static void reserve_range(struct pnp_dev *dev, struct resource *r, int port)
 27{
 28	char *regionid;
 29	const char *pnpid = dev_name(&dev->dev);
 30	resource_size_t start = r->start, end = r->end;
 31	struct resource *res;
 32
 33	regionid = kmalloc(16, GFP_KERNEL);
 34	if (!regionid)
 35		return;
 36
 37	snprintf(regionid, 16, "pnp %s", pnpid);
 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
 45		kfree(regionid);
 46
 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	 */
 52	dev_info(&dev->dev, "%pR %s reserved\n", r,
 53		 res ? "has been" : "could not be");
 54}
 55
 56static void reserve_resources_of_dev(struct pnp_dev *dev)
 57{
 58	struct resource *res;
 59	int i;
 60
 61	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_IO, i)); i++) {
 62		if (res->flags & IORESOURCE_DISABLED)
 63			continue;
 64		if (res->start == 0)
 65			continue;	/* disabled */
 66		if (res->start < 0x100)
 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;
 76		if (res->end < res->start)
 77			continue;	/* invalid */
 78
 79		reserve_range(dev, res, 1);
 80	}
 81
 82	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
 83		if (res->flags & IORESOURCE_DISABLED)
 84			continue;
 85
 86		reserve_range(dev, res, 0);
 87	}
 88}
 89
 90static int system_pnp_probe(struct pnp_dev *dev,
 91			    const struct pnp_device_id *dev_id)
 92{
 93	reserve_resources_of_dev(dev);
 94	return 0;
 95}
 96
 97static struct pnp_driver system_pnp_driver = {
 98	.name     = "system",
 99	.id_table = pnp_dev_table,
100	.flags    = PNP_DRIVER_RES_DO_NOT_CHANGE,
101	.probe    = system_pnp_probe,
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);
v3.1
 
  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(struct pnp_dev *dev, struct resource *r, int port)
 26{
 27	char *regionid;
 28	const char *pnpid = dev_name(&dev->dev);
 29	resource_size_t start = r->start, end = r->end;
 30	struct resource *res;
 31
 32	regionid = kmalloc(16, GFP_KERNEL);
 33	if (!regionid)
 34		return;
 35
 36	snprintf(regionid, 16, "pnp %s", pnpid);
 37	if (port)
 38		res = request_region(start, end - start + 1, regionid);
 39	else
 40		res = request_mem_region(start, end - start + 1, regionid);
 41	if (res)
 42		res->flags &= ~IORESOURCE_BUSY;
 43	else
 44		kfree(regionid);
 45
 46	/*
 47	 * Failures at this point are usually harmless. pci quirks for
 48	 * example do reserve stuff they know about too, so we may well
 49	 * have double reservations.
 50	 */
 51	dev_info(&dev->dev, "%pR %s reserved\n", r,
 52		 res ? "has been" : "could not be");
 53}
 54
 55static void reserve_resources_of_dev(struct pnp_dev *dev)
 56{
 57	struct resource *res;
 58	int i;
 59
 60	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_IO, i)); i++) {
 61		if (res->flags & IORESOURCE_DISABLED)
 62			continue;
 63		if (res->start == 0)
 64			continue;	/* disabled */
 65		if (res->start < 0x100)
 66			/*
 67			 * Below 0x100 is only standard PC hardware
 68			 * (pics, kbd, timer, dma, ...)
 69			 * We should not get resource conflicts there,
 70			 * and the kernel reserves these anyway
 71			 * (see arch/i386/kernel/setup.c).
 72			 * So, do nothing
 73			 */
 74			continue;
 75		if (res->end < res->start)
 76			continue;	/* invalid */
 77
 78		reserve_range(dev, res, 1);
 79	}
 80
 81	for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
 82		if (res->flags & IORESOURCE_DISABLED)
 83			continue;
 84
 85		reserve_range(dev, res, 0);
 86	}
 87}
 88
 89static int system_pnp_probe(struct pnp_dev *dev,
 90			    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};
102
103static int __init pnp_system_init(void)
104{
105	return pnp_register_driver(&system_pnp_driver);
106}
107
108/**
109 * Reserve motherboard resources after PCI claim BARs,
110 * but before PCI assign resources for uninitialized PCI devices
111 */
112fs_initcall(pnp_system_init);