xref: /openbmc/linux/drivers/mtd/maps/sbc_gxx.c (revision 384740dc)
1 /* sbc_gxx.c -- MTD map driver for Arcom Control Systems SBC-MediaGX,
2                 SBC-GXm and SBC-GX1 series boards.
3 
4    Copyright (C) 2001 Arcom Control System Ltd
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 2 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software
18    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 
20 The SBC-MediaGX / SBC-GXx has up to 16 MiB of
21 Intel StrataFlash (28F320/28F640) in x8 mode.
22 
23 This driver uses the CFI probe and Intel Extended Command Set drivers.
24 
25 The flash is accessed as follows:
26 
27    16 KiB memory window at 0xdc000-0xdffff
28 
29    Two IO address locations for paging
30 
31    0x258
32        bit 0-7: address bit 14-21
33    0x259
34        bit 0-1: address bit 22-23
35        bit 7:   0 - reset/powered down
36                 1 - device enabled
37 
38 The single flash device is divided into 3 partition which appear as
39 separate MTD devices.
40 
41 25/04/2001 AJL (Arcom)  Modified signon strings and partition sizes
42                         (to support bzImages up to 638KiB-ish)
43 */
44 
45 // Includes
46 
47 #include <linux/module.h>
48 #include <linux/slab.h>
49 #include <linux/ioport.h>
50 #include <linux/init.h>
51 #include <asm/io.h>
52 
53 #include <linux/mtd/mtd.h>
54 #include <linux/mtd/map.h>
55 #include <linux/mtd/partitions.h>
56 
57 // Defines
58 
59 // - Hardware specific
60 
61 #define WINDOW_START 0xdc000
62 
63 /* Number of bits in offset. */
64 #define WINDOW_SHIFT 14
65 #define WINDOW_LENGTH (1 << WINDOW_SHIFT)
66 
67 /* The bits for the offset into the window. */
68 #define WINDOW_MASK (WINDOW_LENGTH-1)
69 #define PAGE_IO 0x258
70 #define PAGE_IO_SIZE 2
71 
72 /* bit 7 of 0x259 must be 1 to enable device. */
73 #define DEVICE_ENABLE 0x8000
74 
75 // - Flash / Partition sizing
76 
77 #define MAX_SIZE_KiB             16384
78 #define BOOT_PARTITION_SIZE_KiB  768
79 #define DATA_PARTITION_SIZE_KiB  1280
80 #define APP_PARTITION_SIZE_KiB   6144
81 
82 // Globals
83 
84 static volatile int page_in_window = -1; // Current page in window.
85 static void __iomem *iomapadr;
86 static DEFINE_SPINLOCK(sbc_gxx_spin);
87 
88 /* partition_info gives details on the logical partitions that the split the
89  * single flash device into. If the size if zero we use up to the end of the
90  * device. */
91 static struct mtd_partition partition_info[]={
92     { .name = "SBC-GXx flash boot partition",
93       .offset = 0,
94       .size =   BOOT_PARTITION_SIZE_KiB*1024 },
95     { .name = "SBC-GXx flash data partition",
96       .offset = BOOT_PARTITION_SIZE_KiB*1024,
97       .size = (DATA_PARTITION_SIZE_KiB)*1024 },
98     { .name = "SBC-GXx flash application partition",
99       .offset = (BOOT_PARTITION_SIZE_KiB+DATA_PARTITION_SIZE_KiB)*1024 }
100 };
101 
102 #define NUM_PARTITIONS 3
103 
104 static inline void sbc_gxx_page(struct map_info *map, unsigned long ofs)
105 {
106 	unsigned long page = ofs >> WINDOW_SHIFT;
107 
108 	if( page!=page_in_window ) {
109 		outw( page | DEVICE_ENABLE, PAGE_IO );
110 		page_in_window = page;
111 	}
112 }
113 
114 
115 static map_word sbc_gxx_read8(struct map_info *map, unsigned long ofs)
116 {
117 	map_word ret;
118 	spin_lock(&sbc_gxx_spin);
119 	sbc_gxx_page(map, ofs);
120 	ret.x[0] = readb(iomapadr + (ofs & WINDOW_MASK));
121 	spin_unlock(&sbc_gxx_spin);
122 	return ret;
123 }
124 
125 static void sbc_gxx_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
126 {
127 	while(len) {
128 		unsigned long thislen = len;
129 		if (len > (WINDOW_LENGTH - (from & WINDOW_MASK)))
130 			thislen = WINDOW_LENGTH-(from & WINDOW_MASK);
131 
132 		spin_lock(&sbc_gxx_spin);
133 		sbc_gxx_page(map, from);
134 		memcpy_fromio(to, iomapadr + (from & WINDOW_MASK), thislen);
135 		spin_unlock(&sbc_gxx_spin);
136 		to += thislen;
137 		from += thislen;
138 		len -= thislen;
139 	}
140 }
141 
142 static void sbc_gxx_write8(struct map_info *map, map_word d, unsigned long adr)
143 {
144 	spin_lock(&sbc_gxx_spin);
145 	sbc_gxx_page(map, adr);
146 	writeb(d.x[0], iomapadr + (adr & WINDOW_MASK));
147 	spin_unlock(&sbc_gxx_spin);
148 }
149 
150 static void sbc_gxx_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
151 {
152 	while(len) {
153 		unsigned long thislen = len;
154 		if (len > (WINDOW_LENGTH - (to & WINDOW_MASK)))
155 			thislen = WINDOW_LENGTH-(to & WINDOW_MASK);
156 
157 		spin_lock(&sbc_gxx_spin);
158 		sbc_gxx_page(map, to);
159 		memcpy_toio(iomapadr + (to & WINDOW_MASK), from, thislen);
160 		spin_unlock(&sbc_gxx_spin);
161 		to += thislen;
162 		from += thislen;
163 		len -= thislen;
164 	}
165 }
166 
167 static struct map_info sbc_gxx_map = {
168 	.name = "SBC-GXx flash",
169 	.phys = NO_XIP,
170 	.size = MAX_SIZE_KiB*1024, /* this must be set to a maximum possible amount
171 			 of flash so the cfi probe routines find all
172 			 the chips */
173 	.bankwidth = 1,
174 	.read = sbc_gxx_read8,
175 	.copy_from = sbc_gxx_copy_from,
176 	.write = sbc_gxx_write8,
177 	.copy_to = sbc_gxx_copy_to
178 };
179 
180 /* MTD device for all of the flash. */
181 static struct mtd_info *all_mtd;
182 
183 static void cleanup_sbc_gxx(void)
184 {
185 	if( all_mtd ) {
186 		del_mtd_partitions( all_mtd );
187 		map_destroy( all_mtd );
188 	}
189 
190 	iounmap(iomapadr);
191 	release_region(PAGE_IO,PAGE_IO_SIZE);
192 }
193 
194 static int __init init_sbc_gxx(void)
195 {
196   	iomapadr = ioremap(WINDOW_START, WINDOW_LENGTH);
197 	if (!iomapadr) {
198 		printk( KERN_ERR"%s: failed to ioremap memory region\n",
199 			sbc_gxx_map.name );
200 		return -EIO;
201 	}
202 
203 	if (!request_region( PAGE_IO, PAGE_IO_SIZE, "SBC-GXx flash")) {
204 		printk( KERN_ERR"%s: IO ports 0x%x-0x%x in use\n",
205 			sbc_gxx_map.name,
206 			PAGE_IO, PAGE_IO+PAGE_IO_SIZE-1 );
207 		iounmap(iomapadr);
208 		return -EAGAIN;
209 	}
210 
211 
212 	printk( KERN_INFO"%s: IO:0x%x-0x%x MEM:0x%x-0x%x\n",
213 		sbc_gxx_map.name,
214 		PAGE_IO, PAGE_IO+PAGE_IO_SIZE-1,
215 		WINDOW_START, WINDOW_START+WINDOW_LENGTH-1 );
216 
217 	/* Probe for chip. */
218 	all_mtd = do_map_probe( "cfi_probe", &sbc_gxx_map );
219 	if( !all_mtd ) {
220 		cleanup_sbc_gxx();
221 		return -ENXIO;
222 	}
223 
224 	all_mtd->owner = THIS_MODULE;
225 
226 	/* Create MTD devices for each partition. */
227 	add_mtd_partitions(all_mtd, partition_info, NUM_PARTITIONS );
228 
229 	return 0;
230 }
231 
232 module_init(init_sbc_gxx);
233 module_exit(cleanup_sbc_gxx);
234 
235 MODULE_LICENSE("GPL");
236 MODULE_AUTHOR("Arcom Control Systems Ltd.");
237 MODULE_DESCRIPTION("MTD map driver for SBC-GXm and SBC-GX1 series boards");
238