xref: /openbmc/linux/drivers/mtd/maps/sun_uflash.c (revision 87c2ce3b)
1 /* $Id: sun_uflash.c,v 1.13 2005/11/07 11:14:28 gleixner Exp $
2  *
3  * sun_uflash - Driver implementation for user-programmable flash
4  * present on many Sun Microsystems SME boardsets.
5  *
6  * This driver does NOT provide access to the OBP-flash for
7  * safety reasons-- use <linux>/drivers/sbus/char/flash.c instead.
8  *
9  * Copyright (c) 2001 Eric Brower (ebrower@usa.net)
10  *
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/fs.h>
16 #include <linux/errno.h>
17 #include <linux/init.h>
18 #include <linux/ioport.h>
19 #include <asm/ebus.h>
20 #include <asm/oplib.h>
21 #include <asm/uaccess.h>
22 #include <asm/io.h>
23 
24 #include <linux/mtd/mtd.h>
25 #include <linux/mtd/map.h>
26 
27 #define UFLASH_OBPNAME	"flashprom"
28 #define UFLASH_DEVNAME 	"userflash"
29 
30 #define UFLASH_WINDOW_SIZE	0x200000
31 #define UFLASH_BUSWIDTH		1			/* EBus is 8-bit */
32 
33 MODULE_AUTHOR
34 	("Eric Brower <ebrower@usa.net>");
35 MODULE_DESCRIPTION
36 	("User-programmable flash device on Sun Microsystems boardsets");
37 MODULE_SUPPORTED_DEVICE
38 	("userflash");
39 MODULE_LICENSE
40 	("GPL");
41 
42 static LIST_HEAD(device_list);
43 struct uflash_dev {
44 	char *			name;	/* device name */
45 	struct map_info 	map;	/* mtd map info */
46 	struct mtd_info *	mtd;	/* mtd info */
47 	struct list_head	list;
48 };
49 
50 
51 struct map_info uflash_map_templ = {
52 		.name =		"SUNW,???-????",
53 		.size =		UFLASH_WINDOW_SIZE,
54 		.bankwidth =	UFLASH_BUSWIDTH,
55 };
56 
57 int uflash_devinit(struct linux_ebus_device* edev)
58 {
59 	int iTmp, nregs;
60 	struct linux_prom_registers regs[2];
61 	struct uflash_dev *pdev;
62 
63 	iTmp = prom_getproperty(
64 		edev->prom_node, "reg", (void *)regs, sizeof(regs));
65 	if ((iTmp % sizeof(regs[0])) != 0) {
66 		printk("%s: Strange reg property size %d\n",
67 			UFLASH_DEVNAME, iTmp);
68 		return -ENODEV;
69 	}
70 
71 	nregs = iTmp / sizeof(regs[0]);
72 
73 	if (nregs != 1) {
74 		/* Non-CFI userflash device-- once I find one we
75 		 * can work on supporting it.
76 		 */
77 		printk("%s: unsupported device at 0x%lx (%d regs): " \
78 			"email ebrower@usa.net\n",
79 			UFLASH_DEVNAME, edev->resource[0].start, nregs);
80 		return -ENODEV;
81 	}
82 
83 	if(0 == (pdev = kmalloc(sizeof(struct uflash_dev), GFP_KERNEL))) {
84 		printk("%s: unable to kmalloc new device\n", UFLASH_DEVNAME);
85 		return(-ENOMEM);
86 	}
87 
88 	/* copy defaults and tweak parameters */
89 	memcpy(&pdev->map, &uflash_map_templ, sizeof(uflash_map_templ));
90 	pdev->map.size = regs[0].reg_size;
91 
92 	iTmp = prom_getproplen(edev->prom_node, "model");
93 	pdev->name = kmalloc(iTmp, GFP_KERNEL);
94 	prom_getstring(edev->prom_node, "model", pdev->name, iTmp);
95 	if(0 != pdev->name && 0 < strlen(pdev->name)) {
96 		pdev->map.name = pdev->name;
97 	}
98 	pdev->map.phys = edev->resource[0].start;
99 	pdev->map.virt = ioremap_nocache(edev->resource[0].start, pdev->map.size);
100 	if(0 == pdev->map.virt) {
101 		printk("%s: failed to map device\n", __FUNCTION__);
102 		kfree(pdev->name);
103 		kfree(pdev);
104 		return(-1);
105 	}
106 
107 	simple_map_init(&pdev->map);
108 
109 	/* MTD registration */
110 	pdev->mtd = do_map_probe("cfi_probe", &pdev->map);
111 	if(0 == pdev->mtd) {
112 		iounmap(pdev->map.virt);
113 		kfree(pdev->name);
114 		kfree(pdev);
115 		return(-ENXIO);
116 	}
117 
118 	list_add(&pdev->list, &device_list);
119 
120 	pdev->mtd->owner = THIS_MODULE;
121 
122 	add_mtd_device(pdev->mtd);
123 	return(0);
124 }
125 
126 static int __init uflash_init(void)
127 {
128 	struct linux_ebus *ebus = NULL;
129 	struct linux_ebus_device *edev = NULL;
130 
131 	for_each_ebus(ebus) {
132 		for_each_ebusdev(edev, ebus) {
133 			if (!strcmp(edev->prom_name, UFLASH_OBPNAME)) {
134 				if(0 > prom_getproplen(edev->prom_node, "user")) {
135 					DEBUG(2, "%s: ignoring device at 0x%lx\n",
136 							UFLASH_DEVNAME, edev->resource[0].start);
137 				} else {
138 					uflash_devinit(edev);
139 				}
140 			}
141 		}
142 	}
143 
144 	if(list_empty(&device_list)) {
145 		printk("%s: unable to locate device\n", UFLASH_DEVNAME);
146 		return -ENODEV;
147 	}
148 	return(0);
149 }
150 
151 static void __exit uflash_cleanup(void)
152 {
153 	struct list_head *udevlist;
154 	struct uflash_dev *udev;
155 
156 	list_for_each(udevlist, &device_list) {
157 		udev = list_entry(udevlist, struct uflash_dev, list);
158 		DEBUG(2, "%s: removing device %s\n",
159 			UFLASH_DEVNAME, udev->name);
160 
161 		if(0 != udev->mtd) {
162 			del_mtd_device(udev->mtd);
163 			map_destroy(udev->mtd);
164 		}
165 		if(0 != udev->map.virt) {
166 			iounmap(udev->map.virt);
167 			udev->map.virt = NULL;
168 		}
169 		kfree(udev->name);
170 		kfree(udev);
171 	}
172 }
173 
174 module_init(uflash_init);
175 module_exit(uflash_cleanup);
176