[RFC v2 00/24] Re-use nvram module

@@ -1,130 +0,0 @@
-/*
- * /dev/nvram driver for Power Macintosh.
- */
-
-#define NVRAM_VERSION "1.0"
-
-#include <linux/module.h>
-
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <linux/fs.h>
-#include <linux/miscdevice.h>
-#include <linux/fcntl.h>
-#include <linux/nvram.h>
-#include <linux/init.h>
-#include <asm/uaccess.h>
-#include <asm/nvram.h>
-
-#define NVRAM_SIZE	8192
-
-static loff_t nvram_llseek(struct file *file, loff_t offset, int origin)
-{
-	switch (origin) {
-	case 0:
-		break;
-	case 1:
-		offset += file->f_pos;
-		break;
-	case 2:
-		offset += NVRAM_SIZE;
-		break;
-	default:
-		offset = -1;
-	}
-	if (offset < 0)
-		return -EINVAL;
-
-	file->f_pos = offset;
-	return file->f_pos;
-}
-
-static ssize_t read_nvram(struct file *file, char __user *buf,
-			  size_t count, loff_t *ppos)
-{
-	unsigned int i;
-	char __user *p = buf;
-
-	if (!access_ok(VERIFY_WRITE, buf, count))
-		return -EFAULT;
-	if (*ppos >= NVRAM_SIZE)
-		return 0;
-	for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count)
-		if (__put_user(nvram_read_byte(i), p))
-			return -EFAULT;
-	*ppos = i;
-	return p - buf;
-}
-
-static ssize_t write_nvram(struct file *file, const char __user *buf,
-			   size_t count, loff_t *ppos)
-{
-	unsigned int i;
-	const char __user *p = buf;
-	char c;
-
-	if (!access_ok(VERIFY_READ, buf, count))
-		return -EFAULT;
-	if (*ppos >= NVRAM_SIZE)
-		return 0;
-	for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count) {
-		if (__get_user(c, p))
-			return -EFAULT;
-		nvram_write_byte(c, i);
-	}
-	*ppos = i;
-	return p - buf;
-}
-
-static long nvram_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
-	switch(cmd) {
-		case PMAC_NVRAM_GET_OFFSET:
-		{
-			int part, offset;
-			if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0)
-				return -EFAULT;
-			if (part < pmac_nvram_OF || part > pmac_nvram_NR)
-				return -EINVAL;
-			offset = pmac_get_partition(part);
-			if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0)
-				return -EFAULT;
-			break;
-		}
-
-		default:
-			return -EINVAL;
-	}
-
-	return 0;
-}
-
-const struct file_operations nvram_fops = {
-	.owner		= THIS_MODULE,
-	.llseek		= nvram_llseek,
-	.read		= read_nvram,
-	.write		= write_nvram,
-	.unlocked_ioctl	= nvram_ioctl,
-};
-
-static struct miscdevice nvram_dev = {
-	NVRAM_MINOR,
-	"nvram",
-	&nvram_fops
-};
-
-int __init nvram_init(void)
-{
-	printk(KERN_INFO "Macintosh non-volatile memory driver v%s\n",
-		NVRAM_VERSION);
-	return misc_register(&nvram_dev);
-}
-
-void __exit nvram_cleanup(void)
-{
-        misc_deregister( &nvram_dev );
-}
-
-module_init(nvram_init);
-module_exit(nvram_cleanup);
-MODULE_LICENSE("GPL");

@@ -235,21 +235,7 @@ EXPORT_SYMBOL(arch_nvram_ops);
 
 static loff_t nvram_misc_llseek(struct file *file, loff_t offset, int origin)
 {
-	switch (origin) {
-	case 0:
-		/* nothing to do */
-		break;
-	case 1:
-		offset += file->f_pos;
-		break;
-	case 2:
-		offset += NVRAM_BYTES;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	return (offset >= 0) ? (file->f_pos = offset) : -EINVAL;
+	return fixed_size_llseek(file, offset, origin, nvram_size);
 }
 
 static ssize_t nvram_misc_read(struct file *file, char __user *buf,

@@ -0,0 +1,255 @@
+/*
+ * CMOS/NV-RAM driver for Atari. Adapted from drivers/char/nvram.c.
+ * Copyright (C) 1997 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
+ * idea by and with help from Richard Jelinek <rj@suse.de>
+ * Portions copyright (c) 2001,2002 Sun Microsystems (thockin@sun.com)
+ * Further contributions from Cesar Barros, Erik Gilling, Tim Hockin and
+ * Wim Van Sebroeck.
+ */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/mc146818rtc.h>
+#include <linux/module.h>
+#include <linux/nvram.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <asm/atarihw.h>
+#include <asm/atariints.h>
+
+#define NVRAM_BYTES		50
+
+/* It is worth noting that these functions all access bytes of general
+ * purpose memory in the NVRAM - that is to say, they all add the
+ * NVRAM_FIRST_BYTE offset. Pass them offsets into NVRAM as if you did not
+ * know about the RTC cruft.
+ */
+
+/* Note that *all* calls to CMOS_READ and CMOS_WRITE must be done with
+ * rtc_lock held. Due to the index-port/data-port design of the RTC, we
+ * don't want two different things trying to get to it at once. (e.g. the
+ * periodic 11 min sync from kernel/time/ntp.c vs. this driver.)
+ */
+
+unsigned char __nvram_read_byte(int i)
+{
+	return CMOS_READ(NVRAM_FIRST_BYTE + i);
+}
+
+unsigned char nvram_read_byte(int i)
+{
+	unsigned long flags;
+	unsigned char c;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	c = __nvram_read_byte(i);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return c;
+}
+EXPORT_SYMBOL(nvram_read_byte);
+
+/* This races nicely with trying to read with checksum checking */
+void __nvram_write_byte(unsigned char c, int i)
+{
+	CMOS_WRITE(c, NVRAM_FIRST_BYTE + i);
+}
+
+void nvram_write_byte(unsigned char c, int i)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	__nvram_write_byte(c, i);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+}
+
+/* On Ataris, the checksum is over all bytes except the checksum bytes
+ * themselves; these are at the very end.
+ */
+#define ATARI_CKS_RANGE_START	0
+#define ATARI_CKS_RANGE_END	47
+#define ATARI_CKS_LOC		48
+
+int __nvram_check_checksum(void)
+{
+	int i;
+	unsigned char sum = 0;
+
+	for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
+		sum += __nvram_read_byte(i);
+	return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff)) &&
+	       (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff));
+}
+
+int nvram_check_checksum(void)
+{
+	unsigned long flags;
+	int rv;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	rv = __nvram_check_checksum();
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return rv;
+}
+EXPORT_SYMBOL(nvram_check_checksum);
+
+static void __nvram_set_checksum(void)
+{
+	int i;
+	unsigned char sum = 0;
+
+	for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
+		sum += __nvram_read_byte(i);
+	__nvram_write_byte(~sum, ATARI_CKS_LOC);
+	__nvram_write_byte(sum, ATARI_CKS_LOC + 1);
+}
+
+#ifdef CONFIG_PROC_FS
+static struct {
+	unsigned char val;
+	char *name;
+} boot_prefs[] = {
+	{ 0x80, "TOS" },
+	{ 0x40, "ASV" },
+	{ 0x20, "NetBSD (?)" },
+	{ 0x10, "Linux" },
+	{ 0x00, "unspecified" },
+};
+
+static char *languages[] = {
+	"English (US)",
+	"German",
+	"French",
+	"English (UK)",
+	"Spanish",
+	"Italian",
+	"6 (undefined)",
+	"Swiss (French)",
+	"Swiss (German)",
+};
+
+static char *dateformat[] = {
+	"MM%cDD%cYY",
+	"DD%cMM%cYY",
+	"YY%cMM%cDD",
+	"YY%cDD%cMM",
+	"4 (undefined)",
+	"5 (undefined)",
+	"6 (undefined)",
+	"7 (undefined)",
+};
+
+static char *colors[] = {
+	"2", "4", "16", "256", "65536", "??", "??", "??"
+};
+
+static void atari_nvram_proc_read(unsigned char *nvram, struct seq_file *seq,
+                                  void *offset)
+{
+	int checksum;
+	int i;
+	unsigned vmode;
+
+	spin_lock_irq(&rtc_lock);
+	checksum = __nvram_check_checksum();
+	spin_unlock_irq(&rtc_lock);
+
+	seq_printf(seq, "Checksum status  : %svalid\n", checksum ? "" : "not ");
+
+	seq_puts(seq, "Boot preference  : ");
+	for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i)
+		if (nvram[1] == boot_prefs[i].val) {
+			seq_printf(seq, "%s\n", boot_prefs[i].name);
+			break;
+		}
+	if (i < 0)
+		seq_printf(seq, "0x%02x (undefined)\n", nvram[1]);
+
+	seq_printf(seq, "SCSI arbitration : %s\n",
+	           (nvram[16] & 0x80) ? "on" : "off");
+	seq_puts(seq, "SCSI host ID     : ");
+	if (nvram[16] & 0x80)
+		seq_printf(seq, "%d\n", nvram[16] & 7);
+	else
+		seq_puts(seq, "n/a\n");
+
+	if (!MACH_IS_FALCON)
+		return;
+
+	seq_puts(seq, "OS language      : ");
+	if (nvram[6] < ARRAY_SIZE(languages))
+		seq_printf(seq, "%s\n", languages[nvram[6]]);
+	else
+		seq_printf(seq, "%u (undefined)\n", nvram[6]);
+	seq_puts(seq, "Keyboard language: ");
+	if (nvram[7] < ARRAY_SIZE(languages))
+		seq_printf(seq, "%s\n", languages[nvram[7]]);
+	else
+		seq_printf(seq, "%u (undefined)\n", nvram[7]);
+	seq_puts(seq, "Date format      : ");
+	seq_printf(seq, dateformat[nvram[8] & 7],
+	           nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/');
+	seq_printf(seq, ", %dh clock\n", nvram[8] & 16 ? 24 : 12);
+	seq_puts(seq, "Boot delay       : ");
+	if (nvram[10] == 0)
+		seq_puts(seq, "default");
+	else
+		seq_printf(seq, "%ds%s\n", nvram[10],
+		           nvram[10] < 8 ? ", no memory test" : "");
+
+	vmode = (nvram[14] << 8) | nvram[15];
+	seq_printf(seq,
+	           "Video mode       : %s colors, %d columns, %s %s monitor\n",
+	           colors[vmode & 7], vmode & 8 ? 80 : 40,
+	           vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC");
+	seq_printf(seq,
+	           "                   %soverscan, compat. mode %s%s\n",
+	           vmode & 64 ? "" : "no ", vmode & 128 ? "on" : "off",
+	           vmode & 256 ?
+	           (vmode & 16 ? ", line doubling" : ", half screen") : "");
+}
+
+static int nvram_proc_read(struct seq_file *seq, void *offset)
+{
+	unsigned char contents[NVRAM_BYTES];
+	int i;
+
+	spin_lock_irq(&rtc_lock);
+	for (i = 0; i < NVRAM_BYTES; ++i)
+		contents[i] = __nvram_read_byte(i);
+	spin_unlock_irq(&rtc_lock);
+
+	atari_nvram_proc_read(contents, seq, offset);
+
+	return 0;
+}
+
+static int nvram_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, nvram_proc_read, NULL);
+}
+
+static const struct file_operations nvram_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= nvram_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int __init atari_nvram_init(void)
+{
+	if (!(MACH_IS_ATARI && ATARIHW_PRESENT(TT_CLK)))
+		return -ENODEV;
+
+	if (!proc_create("driver/nvram", 0, NULL, &nvram_proc_fops)) {
+		pr_err("nvram: can't create /proc/driver/nvram\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+device_initcall(atari_nvram_init);
+#endif /* CONFIG_PROC_FS */

@@ -6,3 +6,5 @@ obj-y		:= config.o time.o debug.o ataint
 			atasound.o stram.o
 
 obj-$(CONFIG_ATARI_KBD_CORE)	+= atakeyb.o
+
+obj-$(CONFIG_NVRAM:m=y)		+= nvram.o

@@ -21,13 +21,6 @@
  * ioctl(NVRAM_SETCKS) (doesn't change contents, just makes checksum valid
  * again; use with care!)
  *
- * This file also provides some functions for other parts of the kernel that
- * want to access the NVRAM: nvram_{read,write,check_checksum,set_checksum}.
- * Obviously this can be used only if this driver is always configured into
- * the kernel and is not a module. Since the functions are used by some Atari
- * drivers, this is the case on the Atari.
- *
- *
  * 	1.1	Cesar Barros: SMP locking fixes
  * 		added changelog
  * 	1.2	Erik Gilling: Cobalt Networks support

@@ -39,64 +32,6 @@
 
 #include <linux/module.h>
 #include <linux/nvram.h>
-
-#define PC		1
-#define ATARI		2
-
-/* select machine configuration */
-#if defined(CONFIG_ATARI)
-#  define MACH ATARI
-#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__)  /* and ?? */
-#  define MACH PC
-#else
-#  error Cannot build nvram driver for this machine configuration.
-#endif
-
-#if MACH == PC
-
-/* RTC in a PC */
-#define CHECK_DRIVER_INIT()	1
-
-/* On PCs, the checksum is built only over bytes 2..31 */
-#define PC_CKS_RANGE_START	2
-#define PC_CKS_RANGE_END	31
-#define PC_CKS_LOC		32
-#define NVRAM_BYTES		(128-NVRAM_FIRST_BYTE)
-
-#define mach_check_checksum	pc_check_checksum
-#define mach_set_checksum	pc_set_checksum
-#define mach_proc_infos		pc_proc_infos
-
-#endif
-
-#if MACH == ATARI
-
-/* Special parameters for RTC in Atari machines */
-#include <asm/atarihw.h>
-#include <asm/atariints.h>
-#define RTC_PORT(x)		(TT_RTC_BAS + 2*(x))
-#define CHECK_DRIVER_INIT()	(MACH_IS_ATARI && ATARIHW_PRESENT(TT_CLK))
-
-#define NVRAM_BYTES		50
-
-/* On Ataris, the checksum is over all bytes except the checksum bytes
- * themselves; these are at the very end */
-#define ATARI_CKS_RANGE_START	0
-#define ATARI_CKS_RANGE_END	47
-#define ATARI_CKS_LOC		48
-
-#define mach_check_checksum	atari_check_checksum
-#define mach_set_checksum	atari_set_checksum
-#define mach_proc_infos		atari_proc_infos
-
-#endif
-
-/* Note that *all* calls to CMOS_READ and CMOS_WRITE must be done with
- * rtc_lock held. Due to the index-port/data-port design of the RTC, we
- * don't want two different things trying to get to it at once. (e.g. the
- * periodic 11 min sync from kernel/time/ntp.c vs. this driver.)
- */
-
 #include <linux/types.h>
 #include <linux/errno.h>
 #include <linux/miscdevice.h>

@@ -119,12 +54,9 @@ static int nvram_open_mode;	/* special o
 #define NVRAM_WRITE		1 /* opened for writing (exclusive) */
 #define NVRAM_EXCL		2 /* opened with O_EXCL */
 
-static int mach_check_checksum(void);
-static void mach_set_checksum(void);
-
 #ifdef CONFIG_PROC_FS
-static void mach_proc_infos(unsigned char *contents, struct seq_file *seq,
-								void *offset);
+static void pc_nvram_proc_read(unsigned char *contents, struct seq_file *seq,
+                               void *offset);
 #endif
 
 /*

@@ -138,6 +70,14 @@ static void mach_proc_infos(unsigned cha
  * know about the RTC cruft.
  */
 
+#define NVRAM_BYTES		(128 - NVRAM_FIRST_BYTE)
+
+/* Note that *all* calls to CMOS_READ and CMOS_WRITE must be done with
+ * rtc_lock held. Due to the index-port/data-port design of the RTC, we
+ * don't want two different things trying to get to it at once. (e.g. the
+ * periodic 11 min sync from kernel/time/ntp.c vs. this driver.)
+ */
+
 unsigned char __nvram_read_byte(int i)
 {
 	return CMOS_READ(NVRAM_FIRST_BYTE + i);

@@ -173,9 +113,22 @@ void nvram_write_byte(unsigned char c, i
 }
 EXPORT_SYMBOL(nvram_write_byte);
 
+/* On PCs, the checksum is built only over bytes 2..31 */
+#define PC_CKS_RANGE_START	2
+#define PC_CKS_RANGE_END	31
+#define PC_CKS_LOC		32
+
 int __nvram_check_checksum(void)
 {
-	return mach_check_checksum();
+	int i;
+	unsigned short sum = 0;
+	unsigned short expect;
+
+	for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
+		sum += __nvram_read_byte(i);
+	expect = __nvram_read_byte(PC_CKS_LOC)<<8 |
+	    __nvram_read_byte(PC_CKS_LOC+1);
+	return (sum & 0xffff) == expect;
 }
 EXPORT_SYMBOL(__nvram_check_checksum);
 

@@ -193,7 +146,13 @@ EXPORT_SYMBOL(nvram_check_checksum);
 
 static void __nvram_set_checksum(void)
 {
-	mach_set_checksum();
+	int i;
+	unsigned short sum = 0;
+
+	for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
+		sum += __nvram_read_byte(i);
+	__nvram_write_byte(sum >> 8, PC_CKS_LOC);
+	__nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1);
 }
 
 #if 0

@@ -396,7 +355,7 @@ static int nvram_proc_read(struct seq_fi
 		contents[i] = __nvram_read_byte(i);
 	spin_unlock_irq(&rtc_lock);
 
-	mach_proc_infos(contents, seq, offset);
+	pc_nvram_proc_read(contents, seq, offset);
 
 	return 0;
 }

@@ -443,10 +402,6 @@ static int __init nvram_init(void)
 {
 	int ret;
 
-	/* First test whether the driver should init at all */
-	if (!CHECK_DRIVER_INIT())
-		return -ENODEV;
-
 	ret = misc_register(&nvram_dev);
 	if (ret) {
 		printk(KERN_ERR "nvram: can't misc_register on minor=%d\n",

@@ -476,36 +431,6 @@ static void __exit nvram_cleanup_module(
 module_init(nvram_init);
 module_exit(nvram_cleanup_module);
 
-/*
- * Machine specific functions
- */
-
-#if MACH == PC
-
-static int pc_check_checksum(void)
-{
-	int i;
-	unsigned short sum = 0;
-	unsigned short expect;
-
-	for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
-		sum += __nvram_read_byte(i);
-	expect = __nvram_read_byte(PC_CKS_LOC)<<8 |
-	    __nvram_read_byte(PC_CKS_LOC+1);
-	return (sum & 0xffff) == expect;
-}
-
-static void pc_set_checksum(void)
-{
-	int i;
-	unsigned short sum = 0;
-
-	for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
-		sum += __nvram_read_byte(i);
-	__nvram_write_byte(sum >> 8, PC_CKS_LOC);
-	__nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1);
-}
-
 #ifdef CONFIG_PROC_FS
 
 static char *floppy_types[] = {

@@ -520,8 +445,8 @@ static char *gfx_types[] = {
 	"monochrome",
 };
 
-static void pc_proc_infos(unsigned char *nvram, struct seq_file *seq,
-								void *offset)
+static void pc_nvram_proc_read(unsigned char *nvram, struct seq_file *seq,
+                               void *offset)
 {
 	int checksum;
 	int type;

@@ -582,143 +507,8 @@ static void pc_proc_infos(unsigned char
 
 	return;
 }
-#endif
-
-#endif /* MACH == PC */
-
-#if MACH == ATARI
-
-static int atari_check_checksum(void)
-{
-	int i;
-	unsigned char sum = 0;
-
-	for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
-		sum += __nvram_read_byte(i);
-	return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff)) &&
-	    (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff));
-}
-
-static void atari_set_checksum(void)
-{
-	int i;
-	unsigned char sum = 0;
 
-	for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
-		sum += __nvram_read_byte(i);
-	__nvram_write_byte(~sum, ATARI_CKS_LOC);
-	__nvram_write_byte(sum, ATARI_CKS_LOC + 1);
-}
-
-#ifdef CONFIG_PROC_FS
-
-static struct {
-	unsigned char val;
-	char *name;
-} boot_prefs[] = {
-	{ 0x80, "TOS" },
-	{ 0x40, "ASV" },
-	{ 0x20, "NetBSD (?)" },
-	{ 0x10, "Linux" },
-	{ 0x00, "unspecified" }
-};
-
-static char *languages[] = {
-	"English (US)",
-	"German",
-	"French",
-	"English (UK)",
-	"Spanish",
-	"Italian",
-	"6 (undefined)",
-	"Swiss (French)",
-	"Swiss (German)"
-};
-
-static char *dateformat[] = {
-	"MM%cDD%cYY",
-	"DD%cMM%cYY",
-	"YY%cMM%cDD",
-	"YY%cDD%cMM",
-	"4 (undefined)",
-	"5 (undefined)",
-	"6 (undefined)",
-	"7 (undefined)"
-};
-
-static char *colors[] = {
-	"2", "4", "16", "256", "65536", "??", "??", "??"
-};
-
-static void atari_proc_infos(unsigned char *nvram, struct seq_file *seq,
-								void *offset)
-{
-	int checksum = nvram_check_checksum();
-	int i;
-	unsigned vmode;
-
-	seq_printf(seq, "Checksum status  : %svalid\n", checksum ? "" : "not ");
-
-	seq_printf(seq, "Boot preference  : ");
-	for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i) {
-		if (nvram[1] == boot_prefs[i].val) {
-			seq_printf(seq, "%s\n", boot_prefs[i].name);
-			break;
-		}
-	}
-	if (i < 0)
-		seq_printf(seq, "0x%02x (undefined)\n", nvram[1]);
-
-	seq_printf(seq, "SCSI arbitration : %s\n",
-	    (nvram[16] & 0x80) ? "on" : "off");
-	seq_printf(seq, "SCSI host ID     : ");
-	if (nvram[16] & 0x80)
-		seq_printf(seq, "%d\n", nvram[16] & 7);
-	else
-		seq_printf(seq, "n/a\n");
-
-	/* the following entries are defined only for the Falcon */
-	if ((atari_mch_cookie >> 16) != ATARI_MCH_FALCON)
-		return;
-
-	seq_printf(seq, "OS language      : ");
-	if (nvram[6] < ARRAY_SIZE(languages))
-		seq_printf(seq, "%s\n", languages[nvram[6]]);
-	else
-		seq_printf(seq, "%u (undefined)\n", nvram[6]);
-	seq_printf(seq, "Keyboard language: ");
-	if (nvram[7] < ARRAY_SIZE(languages))
-		seq_printf(seq, "%s\n", languages[nvram[7]]);
-	else
-		seq_printf(seq, "%u (undefined)\n", nvram[7]);
-	seq_printf(seq, "Date format      : ");
-	seq_printf(seq, dateformat[nvram[8] & 7],
-	    nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/');
-	seq_printf(seq, ", %dh clock\n", nvram[8] & 16 ? 24 : 12);
-	seq_printf(seq, "Boot delay       : ");
-	if (nvram[10] == 0)
-		seq_printf(seq, "default");
-	else
-		seq_printf(seq, "%ds%s\n", nvram[10],
-		    nvram[10] < 8 ? ", no memory test" : "");
-
-	vmode = (nvram[14] << 8) || nvram[15];
-	seq_printf(seq,
-	    "Video mode       : %s colors, %d columns, %s %s monitor\n",
-	    colors[vmode & 7],
-	    vmode & 8 ? 80 : 40,
-	    vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC");
-	seq_printf(seq, "                   %soverscan, compat. mode %s%s\n",
-	    vmode & 64 ? "" : "no ",
-	    vmode & 128 ? "on" : "off",
-	    vmode & 256 ?
-	    (vmode & 16 ? ", line doubling" : ", half screen") : "");
-
-	return;
-}
-#endif
-
-#endif /* MACH == ATARI */
+#endif /* CONFIG_PROC_FS */
 
 MODULE_LICENSE("GPL");
 MODULE_ALIAS_MISCDEV(NVRAM_MINOR);

@@ -247,7 +247,7 @@ source "drivers/char/hw_random/Kconfig"
 
 config NVRAM
 	tristate "/dev/nvram support"
-	depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
+	depends on X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
 	---help---
 	  If you say Y here and create a character special file /dev/nvram
 	  with major number 10 and minor number 144 using mknod ("man mknod"),

@@ -265,9 +265,6 @@ config NVRAM
 	  should NEVER idly tamper with it. See Ralf Brown's interrupt list
 	  for a guide to the use of CMOS bytes by your BIOS.
 
-	  On Atari machines, /dev/nvram is always configured and does not need
-	  to be selected.
-
 	  To compile this driver as a module, choose M here: the
 	  module will be called nvram.
 

@@ -1592,14 +1592,14 @@ config ATARI_SCSI
 	tristate "Atari native SCSI support"
 	depends on ATARI && SCSI
 	select SCSI_SPI_ATTRS
-	select NVRAM
 	---help---
 	  If you have an Atari with built-in NCR5380 SCSI controller (TT,
 	  Falcon, ...) say Y to get it supported. Of course also, if you have
 	  a compatible SCSI controller (e.g. for Medusa).
 
-	  To compile this driver as a module, choose M here: the
-	  module will be called atari_scsi.
+	  To compile this driver as a module, choose M here: the module will
+	  be called atari_scsi. If you also enable NVRAM support, the SCSI
+	  host's ID is taken from the setting in TT RTC NVRAM.
 
 	  This driver supports both styles of NCR integration into the
 	  system: the TT style (separate DMA), and the Falcon style (via

@@ -875,9 +875,10 @@ static int __init atari_scsi_probe(struc
 	if (ATARIHW_PRESENT(TT_SCSI) && setup_sg_tablesize >= 0)
 		atari_scsi_template.sg_tablesize = setup_sg_tablesize;
 
-	if (setup_hostid >= 0) {
+	if (setup_hostid >= 0)
 		atari_scsi_template.this_id = setup_hostid & 7;
-	} else {
+#ifdef CONFIG_NVRAM
+	else
 		/* Test if a host id is set in the NVRam */
 		if (ATARIHW_PRESENT(TT_CLK) && nvram_check_checksum()) {
 			unsigned char b = nvram_read_byte(14);

@@ -888,8 +889,7 @@ static int __init atari_scsi_probe(struc
 			if (b & 0x80)
 				atari_scsi_template.this_id = b & 7;
 		}
-	}
-
+#endif
 
 #ifdef REAL_DMA
 	/* If running on a Falcon and if there's TT-Ram (i.e., more than one

@@ -38,33 +38,12 @@ unsigned char __nvram_read_byte(int i)
 	return CMOS_READ(NVRAM_FIRST_BYTE + i);
 }
 
-unsigned char nvram_read_byte(int i)
-{
-	unsigned long flags;
-	unsigned char c;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	c = __nvram_read_byte(i);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-	return c;
-}
-EXPORT_SYMBOL(nvram_read_byte);
-
 /* This races nicely with trying to read with checksum checking */
 void __nvram_write_byte(unsigned char c, int i)
 {
 	CMOS_WRITE(c, NVRAM_FIRST_BYTE + i);
 }
 
-void nvram_write_byte(unsigned char c, int i)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	__nvram_write_byte(c, i);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-}
-
 /* On Ataris, the checksum is over all bytes except the checksum bytes
  * themselves; these are at the very end.
  */

@@ -83,18 +62,6 @@ int __nvram_check_checksum(void)
 	       (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff));
 }
 
-int nvram_check_checksum(void)
-{
-	unsigned long flags;
-	int rv;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	rv = __nvram_check_checksum();
-	spin_unlock_irqrestore(&rtc_lock, flags);
-	return rv;
-}
-EXPORT_SYMBOL(nvram_check_checksum);
-
 static void __nvram_set_checksum(void)
 {
 	int i;

@@ -106,6 +73,62 @@ static void __nvram_set_checksum(void)
 	__nvram_write_byte(sum, ATARI_CKS_LOC + 1);
 }
 
+static ssize_t nvram_read(char *buf, size_t count, loff_t *ppos)
+{
+	char *p = buf;
+	loff_t i;
+
+	spin_lock_irq(&rtc_lock);
+
+	if (!__nvram_check_checksum()) {
+		spin_unlock_irq(&rtc_lock);
+		return -EIO;
+	}
+
+	for (i = *ppos; count > 0 && i < NVRAM_BYTES; --count, ++i, ++p)
+		*p = __nvram_read_byte(i);
+
+	spin_unlock_irq(&rtc_lock);
+
+	*ppos = i;
+	return p - buf;
+}
+
+static ssize_t nvram_write(char *buf, size_t count, loff_t *ppos)
+{
+	char *p = buf;
+	loff_t i;
+
+	spin_lock_irq(&rtc_lock);
+
+	if (!__nvram_check_checksum()) {
+		spin_unlock_irq(&rtc_lock);
+		return -EIO;
+	}
+
+	for (i = *ppos; count > 0 && i < NVRAM_BYTES; --count, ++i, ++p)
+		__nvram_write_byte(*p, i);
+
+	__nvram_set_checksum();
+
+	spin_unlock_irq(&rtc_lock);
+
+	*ppos = i;
+	return p - buf;
+}
+
+static ssize_t nvram_get_size(void)
+{
+	return NVRAM_BYTES;
+}
+
+const struct nvram_ops arch_nvram_ops = {
+	.read           = nvram_read,
+	.write          = nvram_write,
+	.get_size       = nvram_get_size,
+};
+EXPORT_SYMBOL(arch_nvram_ops);
+
 #ifdef CONFIG_PROC_FS
 static struct {
 	unsigned char val;

@@ -880,13 +880,15 @@ static int __init atari_scsi_probe(struc
 #ifdef CONFIG_NVRAM
 	else
 		/* Test if a host id is set in the NVRam */
-		if (ATARIHW_PRESENT(TT_CLK) && nvram_check_checksum()) {
-			unsigned char b = nvram_read_byte(14);
+		if (ATARIHW_PRESENT(TT_CLK)) {
+			unsigned char b;
+			loff_t offset = 14;
+			ssize_t count = arch_nvram_ops.read(&b, 1, &offset);
 
 			/* Arbitration enabled? (for TOS)
 			 * If yes, use configured host ID
 			 */
-			if (b & 0x80)
+			if ((count == 1) && (b & 0x80))
 				atari_scsi_template.this_id = b & 7;
 		}
 #endif

@@ -10,4 +10,13 @@ extern void __nvram_write_byte(unsigned
 extern void nvram_write_byte(unsigned char c, int i);
 extern int __nvram_check_checksum(void);
 extern int nvram_check_checksum(void);
+
+struct nvram_ops {
+	ssize_t         (*read)(char *, size_t, loff_t *);
+	ssize_t         (*write)(char *, size_t, loff_t *);
+	ssize_t         (*get_size)(void);
+};
+
+extern const struct nvram_ops arch_nvram_ops;
+
 #endif  /* _LINUX_NVRAM_H */

@@ -51,9 +51,12 @@ static DEFINE_MUTEX(nvram_mutex);
 static DEFINE_SPINLOCK(nvram_state_lock);
 static int nvram_open_cnt;	/* #times opened */
 static int nvram_open_mode;	/* special open modes */
+static ssize_t nvram_size;
 #define NVRAM_WRITE		1 /* opened for writing (exclusive) */
 #define NVRAM_EXCL		2 /* opened with O_EXCL */
 
+#if defined(CONFIG_X86) || defined(CONFIG_ARM)
+
 /*
  * These functions are provided to be called internally or by other parts of
  * the kernel. It's up to the caller to ensure correct checksum before reading

@@ -161,6 +164,20 @@ void nvram_set_checksum(void)
 }
 #endif  /*  0  */
 
+static ssize_t nvram_get_size(void)
+{
+	return NVRAM_BYTES;
+}
+
+const struct nvram_ops arch_nvram_ops = {
+	.read_byte      = nvram_read_byte,
+	.write_byte     = nvram_write_byte,
+	.get_size       = nvram_get_size,
+};
+EXPORT_SYMBOL(arch_nvram_ops);
+
+#endif /* CONFIG_X86 || CONFIG_ARM */
+
 /*
  * The are the file operation function for user access to /dev/nvram
  */

@@ -332,7 +349,7 @@ static int nvram_misc_release(struct ino
 	return 0;
 }
 
-#ifdef CONFIG_PROC_FS
+#if defined(CONFIG_PROC_FS) && (defined(CONFIG_X86) || defined(CONFIG_ARM))
 
 static char *floppy_types[] = {
 	"none", "5.25'' 360k", "5.25'' 1.2M", "3.5'' 720k", "3.5'' 1.44M",

@@ -459,13 +476,20 @@ static int __init nvram_module_init(void
 {
 	int ret;
 
+	if (arch_nvram_ops.get_size == NULL)
+		return -ENODEV;
+
+	nvram_size = arch_nvram_ops.get_size();
+	if (nvram_size < 0)
+		return nvram_size;
+
 	ret = misc_register(&nvram_misc);
 	if (ret) {
 		pr_err("nvram: can't misc_register on minor=%d\n", NVRAM_MINOR);
 		return ret;
 	}
 
-#ifdef CONFIG_PROC_FS
+#if defined(CONFIG_PROC_FS) && (defined(CONFIG_X86) || defined(CONFIG_ARM))
 	if (!proc_create("driver/nvram", 0, NULL, &nvram_proc_fops)) {
 		pr_err("nvram: can't create /proc/driver/nvram\n");
 		misc_deregister(&nvram_misc);

@@ -479,7 +503,7 @@ static int __init nvram_module_init(void
 
 static void __exit nvram_module_exit(void)
 {
-#ifdef CONFIG_PROC_FS
+#if defined(CONFIG_PROC_FS) && (defined(CONFIG_X86) || defined(CONFIG_ARM))
 	remove_proc_entry("driver/nvram", NULL);
 #endif
 	misc_deregister(&nvram_misc);