Commit | Line | Data |
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1da177e4 LT |
1 | /* $Id: flash.c,v 1.25 2001/12/21 04:56:16 davem Exp $ |
2 | * flash.c: Allow mmap access to the OBP Flash, for OBP updates. | |
3 | * | |
4 | * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be) | |
5 | */ | |
6 | ||
7 | #include <linux/config.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/types.h> | |
10 | #include <linux/errno.h> | |
11 | #include <linux/miscdevice.h> | |
12 | #include <linux/slab.h> | |
13 | #include <linux/fcntl.h> | |
14 | #include <linux/poll.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/smp_lock.h> | |
17 | #include <linux/spinlock.h> | |
18 | ||
19 | #include <asm/system.h> | |
20 | #include <asm/uaccess.h> | |
21 | #include <asm/pgtable.h> | |
22 | #include <asm/io.h> | |
23 | #include <asm/sbus.h> | |
24 | #include <asm/ebus.h> | |
25 | #include <asm/upa.h> | |
26 | ||
27 | static DEFINE_SPINLOCK(flash_lock); | |
28 | static struct { | |
29 | unsigned long read_base; /* Physical read address */ | |
30 | unsigned long write_base; /* Physical write address */ | |
31 | unsigned long read_size; /* Size of read area */ | |
32 | unsigned long write_size; /* Size of write area */ | |
33 | unsigned long busy; /* In use? */ | |
34 | } flash; | |
35 | ||
36 | #define FLASH_MINOR 152 | |
37 | ||
38 | static int | |
39 | flash_mmap(struct file *file, struct vm_area_struct *vma) | |
40 | { | |
41 | unsigned long addr; | |
42 | unsigned long size; | |
43 | ||
44 | spin_lock(&flash_lock); | |
45 | if (flash.read_base == flash.write_base) { | |
46 | addr = flash.read_base; | |
47 | size = flash.read_size; | |
48 | } else { | |
49 | if ((vma->vm_flags & VM_READ) && | |
50 | (vma->vm_flags & VM_WRITE)) { | |
51 | spin_unlock(&flash_lock); | |
52 | return -EINVAL; | |
53 | } | |
54 | if (vma->vm_flags & VM_READ) { | |
55 | addr = flash.read_base; | |
56 | size = flash.read_size; | |
57 | } else if (vma->vm_flags & VM_WRITE) { | |
58 | addr = flash.write_base; | |
59 | size = flash.write_size; | |
60 | } else { | |
61 | spin_unlock(&flash_lock); | |
62 | return -ENXIO; | |
63 | } | |
64 | } | |
65 | spin_unlock(&flash_lock); | |
66 | ||
67 | if ((vma->vm_pgoff << PAGE_SHIFT) > size) | |
68 | return -ENXIO; | |
69 | addr = vma->vm_pgoff + (addr >> PAGE_SHIFT); | |
70 | ||
71 | if (vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT)) > size) | |
72 | size = vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT)); | |
73 | ||
74 | pgprot_val(vma->vm_page_prot) &= ~(_PAGE_CACHE); | |
75 | pgprot_val(vma->vm_page_prot) |= _PAGE_E; | |
76 | vma->vm_flags |= (VM_SHM | VM_LOCKED); | |
77 | ||
78 | if (io_remap_pfn_range(vma, vma->vm_start, addr, size, vma->vm_page_prot)) | |
79 | return -EAGAIN; | |
80 | ||
81 | return 0; | |
82 | } | |
83 | ||
84 | static long long | |
85 | flash_llseek(struct file *file, long long offset, int origin) | |
86 | { | |
87 | lock_kernel(); | |
88 | switch (origin) { | |
89 | case 0: | |
90 | file->f_pos = offset; | |
91 | break; | |
92 | case 1: | |
93 | file->f_pos += offset; | |
94 | if (file->f_pos > flash.read_size) | |
95 | file->f_pos = flash.read_size; | |
96 | break; | |
97 | case 2: | |
98 | file->f_pos = flash.read_size; | |
99 | break; | |
100 | default: | |
101 | unlock_kernel(); | |
102 | return -EINVAL; | |
103 | } | |
104 | unlock_kernel(); | |
105 | return file->f_pos; | |
106 | } | |
107 | ||
108 | static ssize_t | |
109 | flash_read(struct file * file, char __user * buf, | |
110 | size_t count, loff_t *ppos) | |
111 | { | |
112 | unsigned long p = file->f_pos; | |
113 | int i; | |
114 | ||
115 | if (count > flash.read_size - p) | |
116 | count = flash.read_size - p; | |
117 | ||
118 | for (i = 0; i < count; i++) { | |
119 | u8 data = upa_readb(flash.read_base + p + i); | |
120 | if (put_user(data, buf)) | |
121 | return -EFAULT; | |
122 | buf++; | |
123 | } | |
124 | ||
125 | file->f_pos += count; | |
126 | return count; | |
127 | } | |
128 | ||
129 | static int | |
130 | flash_open(struct inode *inode, struct file *file) | |
131 | { | |
132 | if (test_and_set_bit(0, (void *)&flash.busy) != 0) | |
133 | return -EBUSY; | |
134 | ||
135 | return 0; | |
136 | } | |
137 | ||
138 | static int | |
139 | flash_release(struct inode *inode, struct file *file) | |
140 | { | |
141 | spin_lock(&flash_lock); | |
142 | flash.busy = 0; | |
143 | spin_unlock(&flash_lock); | |
144 | ||
145 | return 0; | |
146 | } | |
147 | ||
148 | static struct file_operations flash_fops = { | |
149 | /* no write to the Flash, use mmap | |
150 | * and play flash dependent tricks. | |
151 | */ | |
152 | .owner = THIS_MODULE, | |
153 | .llseek = flash_llseek, | |
154 | .read = flash_read, | |
155 | .mmap = flash_mmap, | |
156 | .open = flash_open, | |
157 | .release = flash_release, | |
158 | }; | |
159 | ||
160 | static struct miscdevice flash_dev = { FLASH_MINOR, "flash", &flash_fops }; | |
161 | ||
162 | static int __init flash_init(void) | |
163 | { | |
164 | struct sbus_bus *sbus; | |
165 | struct sbus_dev *sdev = NULL; | |
166 | #ifdef CONFIG_PCI | |
167 | struct linux_ebus *ebus; | |
168 | struct linux_ebus_device *edev = NULL; | |
169 | struct linux_prom_registers regs[2]; | |
170 | int len, nregs; | |
171 | #endif | |
172 | int err; | |
173 | ||
174 | for_all_sbusdev(sdev, sbus) { | |
175 | if (!strcmp(sdev->prom_name, "flashprom")) { | |
176 | if (sdev->reg_addrs[0].phys_addr == sdev->reg_addrs[1].phys_addr) { | |
177 | flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) | | |
178 | (((unsigned long)sdev->reg_addrs[0].which_io)<<32UL); | |
179 | flash.read_size = sdev->reg_addrs[0].reg_size; | |
180 | flash.write_base = flash.read_base; | |
181 | flash.write_size = flash.read_size; | |
182 | } else { | |
183 | flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) | | |
184 | (((unsigned long)sdev->reg_addrs[0].which_io)<<32UL); | |
185 | flash.read_size = sdev->reg_addrs[0].reg_size; | |
186 | flash.write_base = ((unsigned long)sdev->reg_addrs[1].phys_addr) | | |
187 | (((unsigned long)sdev->reg_addrs[1].which_io)<<32UL); | |
188 | flash.write_size = sdev->reg_addrs[1].reg_size; | |
189 | } | |
190 | flash.busy = 0; | |
191 | break; | |
192 | } | |
193 | } | |
194 | if (!sdev) { | |
195 | #ifdef CONFIG_PCI | |
196 | for_each_ebus(ebus) { | |
197 | for_each_ebusdev(edev, ebus) { | |
198 | if (!strcmp(edev->prom_name, "flashprom")) | |
199 | goto ebus_done; | |
200 | } | |
201 | } | |
202 | ebus_done: | |
203 | if (!edev) | |
204 | return -ENODEV; | |
205 | ||
206 | len = prom_getproperty(edev->prom_node, "reg", (void *)regs, sizeof(regs)); | |
207 | if ((len % sizeof(regs[0])) != 0) { | |
208 | printk("flash: Strange reg property size %d\n", len); | |
209 | return -ENODEV; | |
210 | } | |
211 | ||
212 | nregs = len / sizeof(regs[0]); | |
213 | ||
214 | flash.read_base = edev->resource[0].start; | |
215 | flash.read_size = regs[0].reg_size; | |
216 | ||
217 | if (nregs == 1) { | |
218 | flash.write_base = edev->resource[0].start; | |
219 | flash.write_size = regs[0].reg_size; | |
220 | } else if (nregs == 2) { | |
221 | flash.write_base = edev->resource[1].start; | |
222 | flash.write_size = regs[1].reg_size; | |
223 | } else { | |
224 | printk("flash: Strange number of regs %d\n", nregs); | |
225 | return -ENODEV; | |
226 | } | |
227 | ||
228 | flash.busy = 0; | |
229 | ||
230 | #else | |
231 | return -ENODEV; | |
232 | #endif | |
233 | } | |
234 | ||
235 | printk("OBP Flash: RD %lx[%lx] WR %lx[%lx]\n", | |
236 | flash.read_base, flash.read_size, | |
237 | flash.write_base, flash.write_size); | |
238 | ||
239 | err = misc_register(&flash_dev); | |
240 | if (err) { | |
241 | printk(KERN_ERR "flash: unable to get misc minor\n"); | |
242 | return err; | |
243 | } | |
244 | ||
245 | return 0; | |
246 | } | |
247 | ||
248 | static void __exit flash_cleanup(void) | |
249 | { | |
250 | misc_deregister(&flash_dev); | |
251 | } | |
252 | ||
253 | module_init(flash_init); | |
254 | module_exit(flash_cleanup); | |
255 | MODULE_LICENSE("GPL"); |