1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Minimalist driver for a generic PCI-to-EISA bridge.
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * (C) 2003 Marc Zyngier <maz@wild-wind.fr.eu.org>
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Ivan Kokshaysky <ink@jurassic.park.msu.ru> :
8*4882a593Smuzhiyun * Generalisation from i82375 to PCI_CLASS_BRIDGE_EISA.
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include <linux/kernel.h>
12*4882a593Smuzhiyun #include <linux/device.h>
13*4882a593Smuzhiyun #include <linux/eisa.h>
14*4882a593Smuzhiyun #include <linux/pci.h>
15*4882a593Smuzhiyun #include <linux/module.h>
16*4882a593Smuzhiyun #include <linux/init.h>
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun /* There is only *one* pci_eisa device per machine, right ? */
19*4882a593Smuzhiyun static struct eisa_root_device pci_eisa_root;
20*4882a593Smuzhiyun
pci_eisa_init(struct pci_dev * pdev)21*4882a593Smuzhiyun static int __init pci_eisa_init(struct pci_dev *pdev)
22*4882a593Smuzhiyun {
23*4882a593Smuzhiyun int rc, i;
24*4882a593Smuzhiyun struct resource *res, *bus_res = NULL;
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun if ((rc = pci_enable_device (pdev))) {
27*4882a593Smuzhiyun dev_err(&pdev->dev, "Could not enable device\n");
28*4882a593Smuzhiyun return rc;
29*4882a593Smuzhiyun }
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun /*
32*4882a593Smuzhiyun * The Intel 82375 PCI-EISA bridge is a subtractive-decode PCI
33*4882a593Smuzhiyun * device, so the resources available on EISA are the same as those
34*4882a593Smuzhiyun * available on the 82375 bus. This works the same as a PCI-PCI
35*4882a593Smuzhiyun * bridge in subtractive-decode mode (see pci_read_bridge_bases()).
36*4882a593Smuzhiyun * We assume other PCI-EISA bridges are similar.
37*4882a593Smuzhiyun *
38*4882a593Smuzhiyun * eisa_root_register() can only deal with a single io port resource,
39*4882a593Smuzhiyun * so we use the first valid io port resource.
40*4882a593Smuzhiyun */
41*4882a593Smuzhiyun pci_bus_for_each_resource(pdev->bus, res, i)
42*4882a593Smuzhiyun if (res && (res->flags & IORESOURCE_IO)) {
43*4882a593Smuzhiyun bus_res = res;
44*4882a593Smuzhiyun break;
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun if (!bus_res) {
48*4882a593Smuzhiyun dev_err(&pdev->dev, "No resources available\n");
49*4882a593Smuzhiyun return -1;
50*4882a593Smuzhiyun }
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun pci_eisa_root.dev = &pdev->dev;
53*4882a593Smuzhiyun pci_eisa_root.res = bus_res;
54*4882a593Smuzhiyun pci_eisa_root.bus_base_addr = bus_res->start;
55*4882a593Smuzhiyun pci_eisa_root.slots = EISA_MAX_SLOTS;
56*4882a593Smuzhiyun pci_eisa_root.dma_mask = pdev->dma_mask;
57*4882a593Smuzhiyun dev_set_drvdata(pci_eisa_root.dev, &pci_eisa_root);
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun if (eisa_root_register (&pci_eisa_root)) {
60*4882a593Smuzhiyun dev_err(&pdev->dev, "Could not register EISA root\n");
61*4882a593Smuzhiyun return -1;
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun return 0;
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun /*
68*4882a593Smuzhiyun * We have to call pci_eisa_init_early() before pnpacpi_init()/isapnp_init().
69*4882a593Smuzhiyun * Otherwise pnp resource will get enabled early and could prevent eisa
70*4882a593Smuzhiyun * to be initialized.
71*4882a593Smuzhiyun * Also need to make sure pci_eisa_init_early() is called after
72*4882a593Smuzhiyun * x86/pci_subsys_init().
73*4882a593Smuzhiyun * So need to use subsys_initcall_sync with it.
74*4882a593Smuzhiyun */
pci_eisa_init_early(void)75*4882a593Smuzhiyun static int __init pci_eisa_init_early(void)
76*4882a593Smuzhiyun {
77*4882a593Smuzhiyun struct pci_dev *dev = NULL;
78*4882a593Smuzhiyun int ret;
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun for_each_pci_dev(dev)
81*4882a593Smuzhiyun if ((dev->class >> 8) == PCI_CLASS_BRIDGE_EISA) {
82*4882a593Smuzhiyun ret = pci_eisa_init(dev);
83*4882a593Smuzhiyun if (ret)
84*4882a593Smuzhiyun return ret;
85*4882a593Smuzhiyun }
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun return 0;
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun subsys_initcall_sync(pci_eisa_init_early);
90