1 // SPDX-License-Identifier: GPL-2.0-only
2 /* linux/drivers/mtd/maps/scx200_docflash.c
3 
4    Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com>
5 
6    National Semiconductor SCx200 flash mapped with DOCCS
7 */
8 
9 #include <linux/module.h>
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <asm/io.h>
14 #include <linux/mtd/mtd.h>
15 #include <linux/mtd/map.h>
16 #include <linux/mtd/partitions.h>
17 
18 #include <linux/pci.h>
19 #include <linux/scx200.h>
20 
21 #define NAME "scx200_docflash"
22 
23 MODULE_AUTHOR("Christer Weinigel <wingel@hack.org>");
24 MODULE_DESCRIPTION("NatSemi SCx200 DOCCS Flash Driver");
25 MODULE_LICENSE("GPL");
26 
27 static int probe = 0;		/* Don't autoprobe */
28 static unsigned size = 0x1000000; /* 16 MiB the whole ISA address space */
29 static unsigned width = 8;	/* Default to 8 bits wide */
30 static char *flashtype = "cfi_probe";
31 
32 module_param(probe, int, 0);
33 MODULE_PARM_DESC(probe, "Probe for a BIOS mapping");
34 module_param(size, int, 0);
35 MODULE_PARM_DESC(size, "Size of the flash mapping");
36 module_param(width, int, 0);
37 MODULE_PARM_DESC(width, "Data width of the flash mapping (8/16)");
38 module_param(flashtype, charp, 0);
39 MODULE_PARM_DESC(flashtype, "Type of MTD probe to do");
40 
41 static struct resource docmem = {
42 	.flags = IORESOURCE_MEM,
43 	.name  = "NatSemi SCx200 DOCCS Flash",
44 };
45 
46 static struct mtd_info *mymtd;
47 
48 static struct mtd_partition partition_info[] = {
49 	{
50 		.name   = "DOCCS Boot kernel",
51 		.offset = 0,
52 		.size   = 0xc0000
53 	},
54 	{
55 		.name   = "DOCCS Low BIOS",
56 		.offset = 0xc0000,
57 		.size   = 0x40000
58 	},
59 	{
60 		.name   = "DOCCS File system",
61 		.offset = 0x100000,
62 		.size   = ~0	/* calculate from flash size */
63 	},
64 	{
65 		.name   = "DOCCS High BIOS",
66 		.offset = ~0, 	/* calculate from flash size */
67 		.size   = 0x80000
68 	},
69 };
70 #define NUM_PARTITIONS ARRAY_SIZE(partition_info)
71 
72 static struct map_info scx200_docflash_map = {
73 	.name      = "NatSemi SCx200 DOCCS Flash",
74 };
75 
init_scx200_docflash(void)76 static int __init init_scx200_docflash(void)
77 {
78 	unsigned u;
79 	unsigned base;
80 	unsigned ctrl;
81 	unsigned pmr;
82 	struct pci_dev *bridge;
83 
84 	printk(KERN_DEBUG NAME ": NatSemi SCx200 DOCCS Flash Driver\n");
85 
86 	if ((bridge = pci_get_device(PCI_VENDOR_ID_NS,
87 				      PCI_DEVICE_ID_NS_SCx200_BRIDGE,
88 				      NULL)) == NULL)
89 		return -ENODEV;
90 
91 	/* check that we have found the configuration block */
92 	if (!scx200_cb_present()) {
93 		pci_dev_put(bridge);
94 		return -ENODEV;
95 	}
96 
97 	if (probe) {
98 		/* Try to use the present flash mapping if any */
99 		pci_read_config_dword(bridge, SCx200_DOCCS_BASE, &base);
100 		pci_read_config_dword(bridge, SCx200_DOCCS_CTRL, &ctrl);
101 		pci_dev_put(bridge);
102 
103 		pmr = inl(scx200_cb_base + SCx200_PMR);
104 
105 		if (base == 0
106 		    || (ctrl & 0x07000000) != 0x07000000
107 		    || (ctrl & 0x0007ffff) == 0)
108 			return -ENODEV;
109 
110 		size = ((ctrl&0x1fff)<<13) + (1<<13);
111 
112 		for (u = size; u > 1; u >>= 1)
113 			;
114 		if (u != 1)
115 			return -ENODEV;
116 
117 		if (pmr & (1<<6))
118 			width = 16;
119 		else
120 			width = 8;
121 
122 		docmem.start = base;
123 		docmem.end = base + size;
124 
125 		if (request_resource(&iomem_resource, &docmem)) {
126 			printk(KERN_ERR NAME ": unable to allocate memory for flash mapping\n");
127 			return -ENOMEM;
128 		}
129 	} else {
130 		pci_dev_put(bridge);
131 		for (u = size; u > 1; u >>= 1)
132 			;
133 		if (u != 1) {
134 			printk(KERN_ERR NAME ": invalid size for flash mapping\n");
135 			return -EINVAL;
136 		}
137 
138 		if (width != 8 && width != 16) {
139 			printk(KERN_ERR NAME ": invalid bus width for flash mapping\n");
140 			return -EINVAL;
141 		}
142 
143 		if (allocate_resource(&iomem_resource, &docmem,
144 				      size,
145 				      0xc0000000, 0xffffffff,
146 				      size, NULL, NULL)) {
147 			printk(KERN_ERR NAME ": unable to allocate memory for flash mapping\n");
148 			return -ENOMEM;
149 		}
150 
151 		ctrl = 0x07000000 | ((size-1) >> 13);
152 
153 		printk(KERN_INFO "DOCCS BASE=0x%08lx, CTRL=0x%08lx\n", (long)docmem.start, (long)ctrl);
154 
155 		pci_write_config_dword(bridge, SCx200_DOCCS_BASE, docmem.start);
156 		pci_write_config_dword(bridge, SCx200_DOCCS_CTRL, ctrl);
157 		pmr = inl(scx200_cb_base + SCx200_PMR);
158 
159 		if (width == 8) {
160 			pmr &= ~(1<<6);
161 		} else {
162 			pmr |= (1<<6);
163 		}
164 		outl(pmr, scx200_cb_base + SCx200_PMR);
165 	}
166 
167 	printk(KERN_INFO NAME ": DOCCS mapped at %pR, width %d\n",
168 	       &docmem, width);
169 
170 	scx200_docflash_map.size = size;
171 	if (width == 8)
172 		scx200_docflash_map.bankwidth = 1;
173 	else
174 		scx200_docflash_map.bankwidth = 2;
175 
176 	simple_map_init(&scx200_docflash_map);
177 
178 	scx200_docflash_map.phys = docmem.start;
179 	scx200_docflash_map.virt = ioremap(docmem.start, scx200_docflash_map.size);
180 	if (!scx200_docflash_map.virt) {
181 		printk(KERN_ERR NAME ": failed to ioremap the flash\n");
182 		release_resource(&docmem);
183 		return -EIO;
184 	}
185 
186 	mymtd = do_map_probe(flashtype, &scx200_docflash_map);
187 	if (!mymtd) {
188 		printk(KERN_ERR NAME ": unable to detect flash\n");
189 		iounmap(scx200_docflash_map.virt);
190 		release_resource(&docmem);
191 		return -ENXIO;
192 	}
193 
194 	if (size < mymtd->size)
195 		printk(KERN_WARNING NAME ": warning, flash mapping is smaller than flash size\n");
196 
197 	mymtd->owner = THIS_MODULE;
198 
199 	partition_info[3].offset = mymtd->size-partition_info[3].size;
200 	partition_info[2].size = partition_info[3].offset-partition_info[2].offset;
201 	mtd_device_register(mymtd, partition_info, NUM_PARTITIONS);
202 
203 	return 0;
204 }
205 
cleanup_scx200_docflash(void)206 static void __exit cleanup_scx200_docflash(void)
207 {
208 	if (mymtd) {
209 		mtd_device_unregister(mymtd);
210 		map_destroy(mymtd);
211 	}
212 	if (scx200_docflash_map.virt) {
213 		iounmap(scx200_docflash_map.virt);
214 		release_resource(&docmem);
215 	}
216 }
217 
218 module_init(init_scx200_docflash);
219 module_exit(cleanup_scx200_docflash);
220