xref: /openbmc/linux/arch/x86/pci/broadcom_bus.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Read address ranges from a Broadcom CNB20LE Host Bridge
3  *
4  * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the
8  * Free Software Foundation; either version 2 of the License, or (at your
9  * option) any later version.
10  */
11 
12 #include <linux/delay.h>
13 #include <linux/dmi.h>
14 #include <linux/pci.h>
15 #include <linux/init.h>
16 #include <asm/pci_x86.h>
17 
18 #include "bus_numa.h"
19 
20 static void __devinit cnb20le_res(struct pci_dev *dev)
21 {
22 	struct pci_root_info *info;
23 	struct resource res;
24 	u16 word1, word2;
25 	u8 fbus, lbus;
26 	int i;
27 
28 	/*
29 	 * The x86_pci_root_bus_res_quirks() function already refuses to use
30 	 * this information if ACPI _CRS was used. Therefore, we don't bother
31 	 * checking if ACPI is enabled, and just generate the information
32 	 * for both the ACPI _CRS and no ACPI cases.
33 	 */
34 
35 	info = &pci_root_info[pci_root_num];
36 	pci_root_num++;
37 
38 	/* read the PCI bus numbers */
39 	pci_read_config_byte(dev, 0x44, &fbus);
40 	pci_read_config_byte(dev, 0x45, &lbus);
41 	info->bus_min = fbus;
42 	info->bus_max = lbus;
43 
44 	/*
45 	 * Add the legacy IDE ports on bus 0
46 	 *
47 	 * These do not exist anywhere in the bridge registers, AFAICT. I do
48 	 * not have the datasheet, so this is the best I can do.
49 	 */
50 	if (fbus == 0) {
51 		update_res(info, 0x01f0, 0x01f7, IORESOURCE_IO, 0);
52 		update_res(info, 0x03f6, 0x03f6, IORESOURCE_IO, 0);
53 		update_res(info, 0x0170, 0x0177, IORESOURCE_IO, 0);
54 		update_res(info, 0x0376, 0x0376, IORESOURCE_IO, 0);
55 		update_res(info, 0xffa0, 0xffaf, IORESOURCE_IO, 0);
56 	}
57 
58 	/* read the non-prefetchable memory window */
59 	pci_read_config_word(dev, 0xc0, &word1);
60 	pci_read_config_word(dev, 0xc2, &word2);
61 	if (word1 != word2) {
62 		res.start = (word1 << 16) | 0x0000;
63 		res.end   = (word2 << 16) | 0xffff;
64 		res.flags = IORESOURCE_MEM;
65 		update_res(info, res.start, res.end, res.flags, 0);
66 	}
67 
68 	/* read the prefetchable memory window */
69 	pci_read_config_word(dev, 0xc4, &word1);
70 	pci_read_config_word(dev, 0xc6, &word2);
71 	if (word1 != word2) {
72 		res.start = (word1 << 16) | 0x0000;
73 		res.end   = (word2 << 16) | 0xffff;
74 		res.flags = IORESOURCE_MEM | IORESOURCE_PREFETCH;
75 		update_res(info, res.start, res.end, res.flags, 0);
76 	}
77 
78 	/* read the IO port window */
79 	pci_read_config_word(dev, 0xd0, &word1);
80 	pci_read_config_word(dev, 0xd2, &word2);
81 	if (word1 != word2) {
82 		res.start = word1;
83 		res.end   = word2;
84 		res.flags = IORESOURCE_IO;
85 		update_res(info, res.start, res.end, res.flags, 0);
86 	}
87 
88 	/* print information about this host bridge */
89 	res.start = fbus;
90 	res.end   = lbus;
91 	res.flags = IORESOURCE_BUS;
92 	dev_info(&dev->dev, "CNB20LE PCI Host Bridge (domain %04x %pR)\n",
93 			    pci_domain_nr(dev->bus), &res);
94 
95 	for (i = 0; i < info->res_num; i++)
96 		dev_info(&dev->dev, "host bridge window %pR\n", &info->res[i]);
97 }
98 
99 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_LE,
100 			cnb20le_res);
101 
102