[linux.git] / drivers / sbus / char / flash.c

/* $Id: flash.c,v 1.25 2001/12/21 04:56:16 davem Exp $
 * flash.c: Allow mmap access to the OBP Flash, for OBP updates.
 *
 * Copyright (C) 1997  Eddie C. Dost  ([email protected])
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/slab.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/spinlock.h>

#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/sbus.h>
#include <asm/ebus.h>
#include <asm/upa.h>

static DEFINE_SPINLOCK(flash_lock);
static struct {
	unsigned long read_base;	/* Physical read address */
	unsigned long write_base;	/* Physical write address */
	unsigned long read_size;	/* Size of read area */
	unsigned long write_size;	/* Size of write area */
	unsigned long busy;		/* In use? */
} flash;

#define FLASH_MINOR	152

static int
flash_mmap(struct file *file, struct vm_area_struct *vma)
{
	unsigned long addr;
	unsigned long size;

	spin_lock(&flash_lock);
	if (flash.read_base == flash.write_base) {
		addr = flash.read_base;
		size = flash.read_size;
	} else {
		if ((vma->vm_flags & VM_READ) &&
		    (vma->vm_flags & VM_WRITE)) {
			spin_unlock(&flash_lock);
			return -EINVAL;
		}
		if (vma->vm_flags & VM_READ) {
			addr = flash.read_base;
			size = flash.read_size;
		} else if (vma->vm_flags & VM_WRITE) {
			addr = flash.write_base;
			size = flash.write_size;
		} else {
			spin_unlock(&flash_lock);
			return -ENXIO;
		}
	}
	spin_unlock(&flash_lock);

	if ((vma->vm_pgoff << PAGE_SHIFT) > size)
		return -ENXIO;
	addr = vma->vm_pgoff + (addr >> PAGE_SHIFT);

	if (vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT)) > size)
		size = vma->vm_end - (vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT));

	vma->vm_flags |= (VM_SHM | VM_LOCKED);
	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

	if (io_remap_pfn_range(vma, vma->vm_start, addr, size, vma->vm_page_prot))
		return -EAGAIN;
		
	return 0;
}

static long long
flash_llseek(struct file *file, long long offset, int origin)
{
	lock_kernel();
	switch (origin) {
		case 0:
			file->f_pos = offset;
			break;
		case 1:
			file->f_pos += offset;
			if (file->f_pos > flash.read_size)
				file->f_pos = flash.read_size;
			break;
		case 2:
			file->f_pos = flash.read_size;
			break;
		default:
			unlock_kernel();
			return -EINVAL;
	}
	unlock_kernel();
	return file->f_pos;
}

static ssize_t
flash_read(struct file * file, char __user * buf,
	   size_t count, loff_t *ppos)
{
	unsigned long p = file->f_pos;
	int i;
	
	if (count > flash.read_size - p)
		count = flash.read_size - p;

	for (i = 0; i < count; i++) {
		u8 data = upa_readb(flash.read_base + p + i);
		if (put_user(data, buf))
			return -EFAULT;
		buf++;
	}

	file->f_pos += count;
	return count;
}

static int
flash_open(struct inode *inode, struct file *file)
{
	if (test_and_set_bit(0, (void *)&flash.busy) != 0)
		return -EBUSY;

	return 0;
}

static int
flash_release(struct inode *inode, struct file *file)
{
	spin_lock(&flash_lock);
	flash.busy = 0;
	spin_unlock(&flash_lock);

	return 0;
}

static struct file_operations flash_fops = {
	/* no write to the Flash, use mmap
	 * and play flash dependent tricks.
	 */
	.owner =	THIS_MODULE,
	.llseek =	flash_llseek,
	.read =		flash_read,
	.mmap =		flash_mmap,
	.open =		flash_open,
	.release =	flash_release,
};

static struct miscdevice flash_dev = { FLASH_MINOR, "flash", &flash_fops };

static int __init flash_init(void)
{
	struct sbus_bus *sbus;
	struct sbus_dev *sdev = NULL;
#ifdef CONFIG_PCI
	struct linux_ebus *ebus;
	struct linux_ebus_device *edev = NULL;
	struct linux_prom_registers regs[2];
	int len, nregs;
#endif
	int err;

	for_all_sbusdev(sdev, sbus) {
		if (!strcmp(sdev->prom_name, "flashprom")) {
			if (sdev->reg_addrs[0].phys_addr == sdev->reg_addrs[1].phys_addr) {
				flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) |
					(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
				flash.read_size = sdev->reg_addrs[0].reg_size;
				flash.write_base = flash.read_base;
				flash.write_size = flash.read_size;
			} else {
				flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) |
					(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
				flash.read_size = sdev->reg_addrs[0].reg_size;
				flash.write_base = ((unsigned long)sdev->reg_addrs[1].phys_addr) |
					(((unsigned long)sdev->reg_addrs[1].which_io)<<32UL);
				flash.write_size = sdev->reg_addrs[1].reg_size;
			}
			flash.busy = 0;
			break;
		}
	}
	if (!sdev) {
#ifdef CONFIG_PCI
		for_each_ebus(ebus) {
			for_each_ebusdev(edev, ebus) {
				if (!strcmp(edev->prom_name, "flashprom"))
					goto ebus_done;
			}
		}
	ebus_done:
		if (!edev)
			return -ENODEV;

		len = prom_getproperty(edev->prom_node, "reg", (void *)regs, sizeof(regs));
		if ((len % sizeof(regs[0])) != 0) {
			printk("flash: Strange reg property size %d\n", len);
			return -ENODEV;
		}

		nregs = len / sizeof(regs[0]);

		flash.read_base = edev->resource[0].start;
		flash.read_size = regs[0].reg_size;

		if (nregs == 1) {
			flash.write_base = edev->resource[0].start;
			flash.write_size = regs[0].reg_size;
		} else if (nregs == 2) {
			flash.write_base = edev->resource[1].start;
			flash.write_size = regs[1].reg_size;
		} else {
			printk("flash: Strange number of regs %d\n", nregs);
			return -ENODEV;
		}

		flash.busy = 0;

#else
		return -ENODEV;
#endif
	}

	printk("OBP Flash: RD %lx[%lx] WR %lx[%lx]\n",
	       flash.read_base, flash.read_size,
	       flash.write_base, flash.write_size);

	err = misc_register(&flash_dev);
	if (err) {
		printk(KERN_ERR "flash: unable to get misc minor\n");
		return err;
	}

	return 0;
}

static void __exit flash_cleanup(void)
{
	misc_deregister(&flash_dev);
}

module_init(flash_init);
module_exit(flash_cleanup);
MODULE_LICENSE("GPL");
Commit	Line	Data
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 ([email protected])
	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
1da177e4	74	vma->vm_flags \|= (VM_SHM \| VM_LOCKED);
14778d90	75	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1da177e4 LT	76
	77	if (io_remap_pfn_range(vma, vma->vm_start, addr, size, vma->vm_page_prot))
	78	return -EAGAIN;
	79
	80	return 0;
	81	}
	82
	83	static long long
	84	flash_llseek(struct file *file, long long offset, int origin)
	85	{
	86	lock_kernel();
	87	switch (origin) {
	88	case 0:
	89	file->f_pos = offset;
	90	break;
	91	case 1:
	92	file->f_pos += offset;
	93	if (file->f_pos > flash.read_size)
	94	file->f_pos = flash.read_size;
	95	break;
	96	case 2:
	97	file->f_pos = flash.read_size;
	98	break;
	99	default:
	100	unlock_kernel();
	101	return -EINVAL;
	102	}
	103	unlock_kernel();
	104	return file->f_pos;
	105	}
	106
	107	static ssize_t
	108	flash_read(struct file * file, char __user * buf,
	109	size_t count, loff_t *ppos)
	110	{
	111	unsigned long p = file->f_pos;
	112	int i;
	113
	114	if (count > flash.read_size - p)
	115	count = flash.read_size - p;
	116
	117	for (i = 0; i < count; i++) {
	118	u8 data = upa_readb(flash.read_base + p + i);
	119	if (put_user(data, buf))
	120	return -EFAULT;
	121	buf++;
	122	}
	123
	124	file->f_pos += count;
	125	return count;
	126	}
	127
	128	static int
	129	flash_open(struct inode inode, struct file file)
	130	{
	131	if (test_and_set_bit(0, (void *)&flash.busy) != 0)
	132	return -EBUSY;
	133
	134	return 0;
	135	}
	136
	137	static int
	138	flash_release(struct inode inode, struct file file)
	139	{
140	spin_lock(&flash_lock);
141	flash.busy = 0;
142	spin_unlock(&flash_lock);
143
144	return 0;
145	}
146
147	static struct file_operations flash_fops = {
148	/* no write to the Flash, use mmap
149	* and play flash dependent tricks.
150	*/
151	.owner = THIS_MODULE,
152	.llseek = flash_llseek,
153	.read = flash_read,
154	.mmap = flash_mmap,
155	.open = flash_open,
156	.release = flash_release,
157	};
158
159	static struct miscdevice flash_dev = { FLASH_MINOR, "flash", &flash_fops };
160
161	static int __init flash_init(void)
162	{
163	struct sbus_bus *sbus;
164	struct sbus_dev *sdev = NULL;
165	#ifdef CONFIG_PCI
166	struct linux_ebus *ebus;
167	struct linux_ebus_device *edev = NULL;
168	struct linux_prom_registers regs[2];
169	int len, nregs;
170	#endif
171	int err;
172
173	for_all_sbusdev(sdev, sbus) {
174	if (!strcmp(sdev->prom_name, "flashprom")) {
175	if (sdev->reg_addrs[0].phys_addr == sdev->reg_addrs[1].phys_addr) {
176	flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) \|
177	(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
178	flash.read_size = sdev->reg_addrs[0].reg_size;
179	flash.write_base = flash.read_base;
180	flash.write_size = flash.read_size;
181	} else {
182	flash.read_base = ((unsigned long)sdev->reg_addrs[0].phys_addr) \|
183	(((unsigned long)sdev->reg_addrs[0].which_io)<<32UL);
184	flash.read_size = sdev->reg_addrs[0].reg_size;
185	flash.write_base = ((unsigned long)sdev->reg_addrs[1].phys_addr) \|
186	(((unsigned long)sdev->reg_addrs[1].which_io)<<32UL);
187	flash.write_size = sdev->reg_addrs[1].reg_size;
188	}
189	flash.busy = 0;
190	break;
191	}
192	}
193	if (!sdev) {
194	#ifdef CONFIG_PCI
195	for_each_ebus(ebus) {
196	for_each_ebusdev(edev, ebus) {
197	if (!strcmp(edev->prom_name, "flashprom"))
198	goto ebus_done;
199	}
200	}
201	ebus_done:
202	if (!edev)
203	return -ENODEV;
204
205	len = prom_getproperty(edev->prom_node, "reg", (void *)regs, sizeof(regs));
206	if ((len % sizeof(regs[0])) != 0) {
207	printk("flash: Strange reg property size %d\n", len);
208	return -ENODEV;
209	}
210
211	nregs = len / sizeof(regs[0]);
212
213	flash.read_base = edev->resource[0].start;
214	flash.read_size = regs[0].reg_size;
215
216	if (nregs == 1) {
217	flash.write_base = edev->resource[0].start;
218	flash.write_size = regs[0].reg_size;
219	} else if (nregs == 2) {
220	flash.write_base = edev->resource[1].start;
221	flash.write_size = regs[1].reg_size;
222	} else {
223	printk("flash: Strange number of regs %d\n", nregs);
224	return -ENODEV;
225	}
226
227	flash.busy = 0;
228
229	#else
230	return -ENODEV;
231	#endif
232	}
233
234	printk("OBP Flash: RD %lx[%lx] WR %lx[%lx]\n",
235	flash.read_base, flash.read_size,
236	flash.write_base, flash.write_size);
237
238	err = misc_register(&flash_dev);
239	if (err) {
240	printk(KERN_ERR "flash: unable to get misc minor\n");
241	return err;
242	}
243
244	return 0;
245	}
246
247	static void __exit flash_cleanup(void)
248	{
249	misc_deregister(&flash_dev);
250	}
251
252	module_init(flash_init);
253	module_exit(flash_cleanup);
254	MODULE_LICENSE("GPL");