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-rw-r--r--drivers/sbus/char/flash.c255
1 files changed, 255 insertions, 0 deletions
diff --git a/drivers/sbus/char/flash.c b/drivers/sbus/char/flash.c
new file mode 100644
index 0000000..6bdd768
--- /dev/null
+++ b/drivers/sbus/char/flash.c
@@ -0,0 +1,255 @@
+/* $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 (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/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));
+
+ pgprot_val(vma->vm_page_prot) &= ~(_PAGE_CACHE);
+ pgprot_val(vma->vm_page_prot) |= _PAGE_E;
+ vma->vm_flags |= (VM_SHM | VM_LOCKED);
+
+ 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");
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