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1// SPDX-License-Identifier: GPL-2.02/*3 * system.c - a driver for reserving pnp system resources4 *5 * Some code is based on pnpbios_core.c6 * 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 else41 res = request_mem_region(start, end - start + 1, regionid);42 if (res)43 res->flags &= ~IORESOURCE_BUSY;44 else45 kfree(regionid);46 47 /*48 * Failures at this point are usually harmless. pci quirks for49 * example do reserve stuff they know about too, so we may well50 * 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 hardware69 * (pics, kbd, timer, dma, ...)70 * We should not get resource conflicts there,71 * and the kernel reserves these anyway72 * (see arch/i386/kernel/setup.c).73 * So, do nothing74 */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 devices112 */113fs_initcall(pnp_system_init);114