/* $Id: flash.c,v 1.11 1999/03/09 14:06:45 davem Exp $
* flash.c: Allow mmap access to the OBP Flash, for OBP updates.
*
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/malloc.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <linux/init.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>
static struct {
unsigned long read_base;
unsigned long write_base;
unsigned long read_size;
unsigned long write_size;
unsigned long busy;
} flash;
#define FLASH_MINOR 152
static int
flash_mmap(struct file *file, struct vm_area_struct *vma)
{
unsigned long addr;
unsigned long size;
if (vma->vm_offset & ~(PAGE_MASK))
return -ENXIO;
if (flash.read_base == flash.write_base) {
addr = __pa(flash.read_base);
size = flash.read_size;
} else {
if ((vma->vm_flags & VM_READ) &&
(vma->vm_flags & VM_WRITE))
return -EINVAL;
if (vma->vm_flags & VM_READ) {
addr = __pa(flash.read_base);
size = flash.read_size;
} else if (vma->vm_flags & VM_WRITE) {
addr = __pa(flash.write_base);
size = flash.write_size;
} else
return -ENXIO;
}
if (vma->vm_offset > size)
return -ENXIO;
addr += vma->vm_offset;
if (vma->vm_end - (vma->vm_start + vma->vm_offset) > size)
size = vma->vm_end - (vma->vm_start + vma->vm_offset);
pgprot_val(vma->vm_page_prot) &= ~(_PAGE_CACHE);
pgprot_val(vma->vm_page_prot) |= _PAGE_E;
vma->vm_flags |= (VM_SHM | VM_LOCKED);
if (remap_page_range(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)
{
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:
return -EINVAL;
}
return file->f_pos;
}
static ssize_t
flash_read(struct file * file, char * buf,
size_t count, loff_t *ppos)
{
unsigned long p = file->f_pos;
if (count > flash.read_size - p)
count = flash.read_size - p;
if (copy_to_user(buf, flash.read_base + p, count) < 0)
return -EFAULT;
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;
MOD_INC_USE_COUNT;
return 0;
}
static int
flash_release(struct inode *inode, struct file *file)
{
MOD_DEC_USE_COUNT;
flash.busy = 0;
return 0;
}
static struct file_operations flash_fops = {
flash_llseek,
flash_read,
NULL, /* no write to the Flash, use mmap
* and play flash dependent tricks.
*/
NULL, /* readdir */
NULL, /* poll */
NULL, /* ioctl */
flash_mmap,
flash_open,
NULL, /* flush */
flash_release
};
static struct miscdevice flash_dev = { FLASH_MINOR, "flash", &flash_fops };
EXPORT_NO_SYMBOLS;
#ifdef MODULE
int init_module(void)
#else
__initfunc(int flash_init(void))
#endif
{
struct linux_sbus *sbus;
struct linux_sbus_device *sdev = 0;
struct linux_ebus *ebus;
struct linux_ebus_device *edev = 0;
struct linux_prom_registers regs[2];
int len, err, nregs;
for_all_sbusdev(sdev, sbus) {
if (!strcmp(sdev->prom_name, "flashprom")) {
prom_apply_sbus_ranges(sdev->my_bus, &sdev->reg_addrs[0],
sdev->num_registers, sdev);
if (sdev->reg_addrs[0].phys_addr == sdev->reg_addrs[1].phys_addr) {
flash.read_base = (unsigned long)sparc_alloc_io(sdev->reg_addrs[0].phys_addr, 0,
sdev->reg_addrs[0].reg_size, "flashprom",
sdev->reg_addrs[0].which_io, 0);
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)sparc_alloc_io(sdev->reg_addrs[0].phys_addr, 0,
sdev->reg_addrs[0].reg_size, "flashprom",
sdev->reg_addrs[0].which_io, 0);
flash.read_size = sdev->reg_addrs[0].reg_size;
flash.write_base = (unsigned long)sparc_alloc_io(sdev->reg_addrs[1].phys_addr, 0,
sdev->reg_addrs[1].reg_size, "flashprom",
sdev->reg_addrs[1].which_io, 0);
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->base_address[0];
flash.read_size = regs[0].reg_size;
if (nregs == 1) {
flash.write_base = edev->base_address[0];
flash.write_size = regs[0].reg_size;
} else if (nregs == 2) {
flash.write_base = edev->base_address[1];
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",
__pa(flash.read_base), flash.read_size,
__pa(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;
}
#ifdef MODULE
void cleanup_module(void)
{
misc_deregister(&flash_dev);
}
#endif