1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * BIOS Flash chip on Intel 440GX board.
4 *
5 * Bugs this currently does not work under linuxBIOS.
6 */
7
8#include <linux/module.h>
9#include <linux/pci.h>
10#include <linux/kernel.h>
11#include <linux/init.h>
12#include <asm/io.h>
13#include <linux/mtd/mtd.h>
14#include <linux/mtd/map.h>
15
16#define PIIXE_IOBASE_RESOURCE 11
17
18#define WINDOW_ADDR 0xfff00000
19#define WINDOW_SIZE 0x00100000
20#define BUSWIDTH 1
21
22static u32 iobase;
23#define IOBASE iobase
24#define TRIBUF_PORT (IOBASE+0x37)
25#define VPP_PORT (IOBASE+0x28)
26
27static struct mtd_info *mymtd;
28
29
30/* Is this really the vpp port? */
31static DEFINE_SPINLOCK(l440gx_vpp_lock);
32static int l440gx_vpp_refcnt;
33static void l440gx_set_vpp(struct map_info *map, int vpp)
34{
35 unsigned long flags;
36
37 spin_lock_irqsave(&l440gx_vpp_lock, flags);
38 if (vpp) {
39 if (++l440gx_vpp_refcnt == 1) /* first nested 'on' */
40 outl(inl(VPP_PORT) | 1, VPP_PORT);
41 } else {
42 if (--l440gx_vpp_refcnt == 0) /* last nested 'off' */
43 outl(inl(VPP_PORT) & ~1, VPP_PORT);
44 }
45 spin_unlock_irqrestore(lock: &l440gx_vpp_lock, flags);
46}
47
48static struct map_info l440gx_map = {
49 .name = "L440GX BIOS",
50 .size = WINDOW_SIZE,
51 .bankwidth = BUSWIDTH,
52 .phys = WINDOW_ADDR,
53#if 0
54 /* FIXME verify that this is the
55 * appripriate code for vpp enable/disable
56 */
57 .set_vpp = l440gx_set_vpp
58#endif
59};
60
61static int __init init_l440gx(void)
62{
63 struct pci_dev *dev, *pm_dev;
64 struct resource *pm_iobase;
65 __u16 word;
66
67 dev = pci_get_device(PCI_VENDOR_ID_INTEL,
68 PCI_DEVICE_ID_INTEL_82371AB_0, NULL);
69
70 pm_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
71 PCI_DEVICE_ID_INTEL_82371AB_3, NULL);
72
73 pci_dev_put(dev);
74
75 if (!dev || !pm_dev) {
76 printk(KERN_NOTICE "L440GX flash mapping: failed to find PIIX4 ISA bridge, cannot continue\n");
77 pci_dev_put(dev: pm_dev);
78 return -ENODEV;
79 }
80
81 l440gx_map.virt = ioremap(WINDOW_ADDR, WINDOW_SIZE);
82
83 if (!l440gx_map.virt) {
84 printk(KERN_WARNING "Failed to ioremap L440GX flash region\n");
85 pci_dev_put(dev: pm_dev);
86 return -ENOMEM;
87 }
88 simple_map_init(&l440gx_map);
89 pr_debug("window_addr = %p\n", l440gx_map.virt);
90
91 /* Setup the pm iobase resource
92 * This code should move into some kind of generic bridge
93 * driver but for the moment I'm content with getting the
94 * allocation correct.
95 */
96 pm_iobase = &pm_dev->resource[PIIXE_IOBASE_RESOURCE];
97 if (!(pm_iobase->flags & IORESOURCE_IO)) {
98 pm_iobase->name = "pm iobase";
99 pm_iobase->start = 0;
100 pm_iobase->end = 63;
101 pm_iobase->flags = IORESOURCE_IO;
102
103 /* Put the current value in the resource */
104 pci_read_config_dword(dev: pm_dev, where: 0x40, val: &iobase);
105 iobase &= ~1;
106 pm_iobase->start += iobase & ~1;
107 pm_iobase->end += iobase & ~1;
108
109 pci_dev_put(dev: pm_dev);
110
111 /* Allocate the resource region */
112 if (pci_assign_resource(dev: pm_dev, PIIXE_IOBASE_RESOURCE) != 0) {
113 pci_dev_put(dev);
114 pci_dev_put(dev: pm_dev);
115 printk(KERN_WARNING "Could not allocate pm iobase resource\n");
116 iounmap(addr: l440gx_map.virt);
117 return -ENXIO;
118 }
119 }
120 /* Set the iobase */
121 iobase = pm_iobase->start;
122 pci_write_config_dword(dev: pm_dev, where: 0x40, val: iobase | 1);
123
124
125 /* Set XBCS# */
126 pci_read_config_word(dev, where: 0x4e, val: &word);
127 word |= 0x4;
128 pci_write_config_word(dev, where: 0x4e, val: word);
129
130 /* Supply write voltage to the chip */
131 l440gx_set_vpp(map: &l440gx_map, vpp: 1);
132
133 /* Enable the gate on the WE line */
134 outb(inb(TRIBUF_PORT) & ~1, TRIBUF_PORT);
135
136 printk(KERN_NOTICE "Enabled WE line to L440GX BIOS flash chip.\n");
137
138 mymtd = do_map_probe(name: "jedec_probe", map: &l440gx_map);
139 if (!mymtd) {
140 printk(KERN_NOTICE "JEDEC probe on BIOS chip failed. Using ROM\n");
141 mymtd = do_map_probe(name: "map_rom", map: &l440gx_map);
142 }
143 if (mymtd) {
144 mymtd->owner = THIS_MODULE;
145
146 mtd_device_register(mymtd, NULL, 0);
147 return 0;
148 }
149
150 iounmap(addr: l440gx_map.virt);
151 return -ENXIO;
152}
153
154static void __exit cleanup_l440gx(void)
155{
156 mtd_device_unregister(master: mymtd);
157 map_destroy(mtd: mymtd);
158
159 iounmap(addr: l440gx_map.virt);
160}
161
162module_init(init_l440gx);
163module_exit(cleanup_l440gx);
164
165MODULE_LICENSE("GPL");
166MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
167MODULE_DESCRIPTION("MTD map driver for BIOS chips on Intel L440GX motherboards");
168

source code of linux/drivers/mtd/maps/l440gx.c