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1 #include <linux/sched.h>
2 #include <linux/mm.h>
3 #include <linux/uaccess.h>
4 #include <linux/mmzone.h>
5 #include <linux/ioport.h>
6 #include <linux/seq_file.h>
7 #include <linux/console.h>
8 #include <linux/init.h>
9 #include <linux/edd.h>
10 #include <linux/dmi.h>
11 #include <linux/pfn.h>
12 #include <linux/pci.h>
13 #include <asm/pci-direct.h>
14 
15 
16 #include <asm/e820.h>
17 #include <asm/mmzone.h>
18 #include <asm/setup.h>
19 #include <asm/sections.h>
20 #include <asm/io.h>
21 #include <setup_arch.h>
22 
23 static struct resource system_rom_resource = {
24 	.name	= "System ROM",
25 	.start	= 0xf0000,
26 	.end	= 0xfffff,
27 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
28 };
29 
30 static struct resource extension_rom_resource = {
31 	.name	= "Extension ROM",
32 	.start	= 0xe0000,
33 	.end	= 0xeffff,
34 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
35 };
36 
37 static struct resource adapter_rom_resources[] = { {
38 	.name 	= "Adapter ROM",
39 	.start	= 0xc8000,
40 	.end	= 0,
41 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
42 }, {
43 	.name 	= "Adapter ROM",
44 	.start	= 0,
45 	.end	= 0,
46 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
47 }, {
48 	.name 	= "Adapter ROM",
49 	.start	= 0,
50 	.end	= 0,
51 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
52 }, {
53 	.name 	= "Adapter ROM",
54 	.start	= 0,
55 	.end	= 0,
56 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
57 }, {
58 	.name 	= "Adapter ROM",
59 	.start	= 0,
60 	.end	= 0,
61 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
62 }, {
63 	.name 	= "Adapter ROM",
64 	.start	= 0,
65 	.end	= 0,
66 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
67 } };
68 
69 static struct resource video_rom_resource = {
70 	.name 	= "Video ROM",
71 	.start	= 0xc0000,
72 	.end	= 0xc7fff,
73 	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
74 };
75 
76 #define ROMSIGNATURE 0xaa55
77 
romsignature(const unsigned char * rom)78 static int __init romsignature(const unsigned char *rom)
79 {
80 	const unsigned short * const ptr = (const unsigned short *)rom;
81 	unsigned short sig;
82 
83 	return probe_kernel_address(ptr, sig) == 0 && sig == ROMSIGNATURE;
84 }
85 
romchecksum(const unsigned char * rom,unsigned long length)86 static int __init romchecksum(const unsigned char *rom, unsigned long length)
87 {
88 	unsigned char sum, c;
89 
90 	for (sum = 0; length && probe_kernel_address(rom++, c) == 0; length--)
91 		sum += c;
92 	return !length && !sum;
93 }
94 
probe_roms(void)95 void __init probe_roms(void)
96 {
97 	const unsigned char *rom;
98 	unsigned long start, length, upper;
99 	unsigned char c;
100 	int i;
101 
102 	/* video rom */
103 	upper = adapter_rom_resources[0].start;
104 	for (start = video_rom_resource.start; start < upper; start += 2048) {
105 		rom = isa_bus_to_virt(start);
106 		if (!romsignature(rom))
107 			continue;
108 
109 		video_rom_resource.start = start;
110 
111 		if (probe_kernel_address(rom + 2, c) != 0)
112 			continue;
113 
114 		/* 0 < length <= 0x7f * 512, historically */
115 		length = c * 512;
116 
117 		/* if checksum okay, trust length byte */
118 		if (length && romchecksum(rom, length))
119 			video_rom_resource.end = start + length - 1;
120 
121 		request_resource(&iomem_resource, &video_rom_resource);
122 		break;
123 	}
124 
125 	start = (video_rom_resource.end + 1 + 2047) & ~2047UL;
126 	if (start < upper)
127 		start = upper;
128 
129 	/* system rom */
130 	request_resource(&iomem_resource, &system_rom_resource);
131 	upper = system_rom_resource.start;
132 
133 	/* check for extension rom (ignore length byte!) */
134 	rom = isa_bus_to_virt(extension_rom_resource.start);
135 	if (romsignature(rom)) {
136 		length = extension_rom_resource.end - extension_rom_resource.start + 1;
137 		if (romchecksum(rom, length)) {
138 			request_resource(&iomem_resource, &extension_rom_resource);
139 			upper = extension_rom_resource.start;
140 		}
141 	}
142 
143 	/* check for adapter roms on 2k boundaries */
144 	for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) {
145 		rom = isa_bus_to_virt(start);
146 		if (!romsignature(rom))
147 			continue;
148 
149 		if (probe_kernel_address(rom + 2, c) != 0)
150 			continue;
151 
152 		/* 0 < length <= 0x7f * 512, historically */
153 		length = c * 512;
154 
155 		/* but accept any length that fits if checksum okay */
156 		if (!length || start + length > upper || !romchecksum(rom, length))
157 			continue;
158 
159 		adapter_rom_resources[i].start = start;
160 		adapter_rom_resources[i].end = start + length - 1;
161 		request_resource(&iomem_resource, &adapter_rom_resources[i]);
162 
163 		start = adapter_rom_resources[i++].end & ~2047UL;
164 	}
165 }
166 
167