Split /dev/nvram driver out of isa/clock.c for i386 and amd64. I have not

refactored it to be a generic device.
Instead of being part of the standard kernel, there is now a 'nvram' device
for i386/amd64.  It is in DEFAULTS like io and mem, and can be turned off
with 'nodevice nvram'.  This matches the previous behavior when it was
first committed.

12 files changed, 182 insertions, 292 deletions

diff --git a/sys/amd64/conf/DEFAULTS b/sys/amd64/conf/DEFAULTS
index e98b169..519198c 100644
--- a/sys/amd64/conf/DEFAULTS
+++ b/sys/amd64/conf/DEFAULTS
@@ -11,6 +11,7 @@ device		isa
 # Pseudo devices.
 device		mem		# Memory and kernel memory devices
 device		io		# I/O device
+device		nvram		# Access to rtc cmos via /dev/nvram
 
 # UART chips on this platform
 device		uart_ns8250
diff --git a/sys/amd64/include/clock.h b/sys/amd64/include/clock.h
index 30c2f26..9a6876e 100644
--- a/sys/amd64/include/clock.h
+++ b/sys/amd64/include/clock.h
@@ -31,7 +31,8 @@ void	i8254_init(void);
 
 int	acquire_timer2(int mode);
 int	release_timer2(void);
-int	rtcin(int val);
+int	rtcin(int reg);
+void	writertc(int reg, unsigned char val);
 int	sysbeep(int pitch, int period);
 void	init_TSC(void);
 void	init_TSC_tc(void);
diff --git a/sys/amd64/isa/clock.c b/sys/amd64/isa/clock.c
index 0e5c8fc..2809828 100644
--- a/sys/amd64/isa/clock.c
+++ b/sys/amd64/isa/clock.c
@@ -433,7 +433,7 @@ rtcin(reg)
 	return (val);
 }
 
-static void
+void
 writertc(int reg, u_char val)
 {
 
@@ -934,99 +934,4 @@ static devclass_t attimer_devclass;
 DRIVER_MODULE(attimer, isa, attimer_driver, attimer_devclass, 0, 0);
 DRIVER_MODULE(attimer, acpi, attimer_driver, attimer_devclass, 0, 0);
 
-/*
- * Linux-style /dev/nvram driver
- *
- * cmos ram starts at bytes 14 through 128, for a total of 114 bytes.
- * bytes 16 through 31 are checksummed at byte 32.
- * Unlike Linux, you have to take care of the checksums yourself.
- * The driver exposes byte 14 as file offset 0.
- */
-
-#define NVRAM_FIRST	RTC_DIAG	/* 14 */
-#define NVRAM_LAST	128
-
-static d_open_t		nvram_open;
-static d_read_t		nvram_read;
-static d_write_t	nvram_write;
-
-static struct cdev *nvram_dev;
-
-static struct cdevsw nvram_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_flags =	D_NEEDGIANT,
-	.d_open =	nvram_open,
-	.d_read =	nvram_read,
-	.d_write =	nvram_write,
-	.d_name =	"nvram",
-};
-
-static int
-nvram_open(struct cdev *dev __unused, int flags, int fmt __unused,
-    struct thread *td)
-{
-	int error = 0;
-
-	if (flags & FWRITE)
-		error = securelevel_gt(td->td_ucred, 0);
-
-	return (error);
-}
-
-static int
-nvram_read(struct cdev *dev, struct uio *uio, int flags)
-{
-	int nv_off;
-	u_char v;
-	int error = 0;
-
-	while (uio->uio_resid > 0 && error == 0) {
-		nv_off = uio->uio_offset + NVRAM_FIRST;
-		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
-			return (0);	/* Signal EOF */
-		/* Single byte at a time */
-		v = rtcin(nv_off);
-		error = uiomove(&v, 1, uio);
-	}
-	return (error);
-
-}
-
-static int
-nvram_write(struct cdev *dev, struct uio *uio, int flags)
-{
-	int nv_off;
-	u_char v;
-	int error = 0;
-
-	while (uio->uio_resid > 0 && error == 0) {
-		nv_off = uio->uio_offset + NVRAM_FIRST;
-		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
-			return (0);	/* Signal EOF */
-		/* Single byte at a time */
-		error = uiomove(&v, 1, uio);
-		writertc(nv_off, v);
-	}
-	return (error);
-}
-
-static int
-nvram_modevent(module_t mod __unused, int type, void *data __unused)
-{
-	switch (type) {
-	case MOD_LOAD:
-		nvram_dev = make_dev(&nvram_cdevsw, 0,
-		    UID_ROOT, GID_KMEM, 0640, "nvram");
-		break;
-	case MOD_UNLOAD:
-	case MOD_SHUTDOWN:
-		destroy_dev(nvram_dev);
-		break;
-	default:
-		return (EOPNOTSUPP);
-	}
-	return (0);
-}
-DEV_MODULE(nvram, nvram_modevent, NULL);
-
 #endif /* DEV_ISA */
diff --git a/sys/conf/files.amd64 b/sys/conf/files.amd64
index 00d3263..f3e6a76 100644
--- a/sys/conf/files.amd64
+++ b/sys/conf/files.amd64
@@ -185,6 +185,7 @@ dev/kbd/kbd.c			optional	atkbd | sc | ukbd
 dev/mem/memutil.c		optional	mem
 dev/nfe/if_nfe.c		optional	nfe pci
 dev/nve/if_nve.c		optional	nve pci
+dev/nvram/nvram.c		optional	nvram isa
 dev/rr232x/os_bsd.c		optional	rr232x
 dev/rr232x/osm_bsd.c		optional	rr232x
 dev/rr232x/rr232x_config.c	optional	rr232x
diff --git a/sys/conf/files.i386 b/sys/conf/files.i386
index 87c4a23..15d2150 100644
--- a/sys/conf/files.i386
+++ b/sys/conf/files.i386
@@ -211,6 +211,7 @@ dev/mse/mse.c			optional mse
 dev/mse/mse_isa.c		optional mse isa
 dev/nfe/if_nfe.c		optional nfe pci
 dev/nve/if_nve.c		optional nve pci
+dev/nvram/nvram.c		optional nvram isa
 dev/pcf/pcf_isa.c		optional pcf
 dev/random/nehemiah.c		optional random
 dev/rr232x/os_bsd.c		optional rr232x
diff --git a/sys/dev/nvram/nvram.c b/sys/dev/nvram/nvram.c
new file mode 100644
index 0000000..fde9d88
--- /dev/null
+++ b/sys/dev/nvram/nvram.c
@@ -0,0 +1,159 @@
+/*-
+ * Copyright (c) 2007 Peter Wemm
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/conf.h>
+#include <sys/fcntl.h>
+#include <sys/proc.h>
+#include <sys/uio.h>
+#include <sys/module.h>
+
+#include <machine/clock.h>
+#include <isa/rtc.h>
+
+/*
+ * Linux-style /dev/nvram driver
+ *
+ * cmos ram starts at bytes 14 through 128, for a total of 114 bytes.
+ * The driver exposes byte 14 as file offset 0.
+ *
+ * Offsets 2 through 31 are checksummed at offset 32, 33.
+ * In order to avoid the possibility of making the machine unbootable at the
+ * bios level (press F1 to continue!), we refuse to allow writes if we do
+ * not see a pre-existing valid checksum.  If the existing sum is invalid,
+ * then presumably we do not know how to make a sum that the bios will accept.
+ */
+
+#define NVRAM_FIRST	RTC_DIAG	/* 14 */
+#define NVRAM_LAST	128
+
+#define CKSUM_FIRST	2
+#define CKSUM_LAST	31
+#define CKSUM_MSB	32
+#define CKSUM_LSB	33
+
+static d_open_t		nvram_open;
+static d_read_t		nvram_read;
+static d_write_t	nvram_write;
+
+static struct cdev *nvram_dev;
+
+static struct cdevsw nvram_cdevsw = {
+	.d_version =	D_VERSION,
+	.d_flags =	D_NEEDGIANT,
+	.d_open =	nvram_open,
+	.d_read =	nvram_read,
+	.d_write =	nvram_write,
+	.d_name =	"nvram",
+};
+
+static int
+nvram_open(struct cdev *dev __unused, int flags, int fmt __unused,
+    struct thread *td)
+{
+	int error = 0;
+
+	if (flags & FWRITE)
+		error = securelevel_gt(td->td_ucred, 0);
+
+	return (error);
+}
+
+static int
+nvram_read(struct cdev *dev, struct uio *uio, int flags)
+{
+	int nv_off;
+	u_char v;
+	int error = 0;
+
+	while (uio->uio_resid > 0 && error == 0) {
+		nv_off = uio->uio_offset + NVRAM_FIRST;
+		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
+			return (0);	/* Signal EOF */
+		/* Single byte at a time */
+		v = rtcin(nv_off);
+		error = uiomove(&v, 1, uio);
+	}
+	return (error);
+
+}
+
+static int
+nvram_write(struct cdev *dev, struct uio *uio, int flags)
+{
+	int nv_off;
+	u_char v;
+	int error = 0;
+	int i;
+	uint16_t sum;
+
+	/* Assert that we understand the existing checksum first!  */
+	sum = rtcin(NVRAM_FIRST + CKSUM_MSB) << 8 |
+	      rtcin(NVRAM_FIRST + CKSUM_LSB);
+	for (i = CKSUM_FIRST; i <= CKSUM_LAST; i++)
+		sum -= rtcin(NVRAM_FIRST + i);
+	if (sum != 0)
+		return (EIO);
+	/* Bring in user data and write */
+	while (uio->uio_resid > 0 && error == 0) {
+		nv_off = uio->uio_offset + NVRAM_FIRST;
+		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
+			return (0);	/* Signal EOF */
+		/* Single byte at a time */
+		error = uiomove(&v, 1, uio);
+		writertc(nv_off, v);
+	}
+	/* Recalculate checksum afterwards */
+	sum = 0;
+	for (i = CKSUM_FIRST; i <= CKSUM_LAST; i++)
+		sum += rtcin(NVRAM_FIRST + i);
+	writertc(NVRAM_FIRST + CKSUM_MSB, sum >> 8);
+	writertc(NVRAM_FIRST + CKSUM_LSB, sum);
+	return (error);
+}
+
+static int
+nvram_modevent(module_t mod __unused, int type, void *data __unused)
+{
+	switch (type) {
+	case MOD_LOAD:
+		nvram_dev = make_dev(&nvram_cdevsw, 0,
+		    UID_ROOT, GID_KMEM, 0640, "nvram");
+		break;
+	case MOD_UNLOAD:
+	case MOD_SHUTDOWN:
+		destroy_dev(nvram_dev);
+		break;
+	default:
+		return (EOPNOTSUPP);
+	}
+	return (0);
+}
+DEV_MODULE(nvram, nvram_modevent, NULL);
diff --git a/sys/i386/conf/DEFAULTS b/sys/i386/conf/DEFAULTS
index a5f69a1..2e459f0 100644
--- a/sys/i386/conf/DEFAULTS
+++ b/sys/i386/conf/DEFAULTS
@@ -15,6 +15,7 @@ device		npx
 # Pseudo devices.
 device		mem		# Memory and kernel memory devices
 device		io		# I/O device
+device		nvram		# Access to rtc cmos via /dev/nvram
 
 # UART chips on this platform
 device		uart_ns8250
diff --git a/sys/i386/include/clock.h b/sys/i386/include/clock.h
index a91b252..9bdd421 100644
--- a/sys/i386/include/clock.h
+++ b/sys/i386/include/clock.h
@@ -31,7 +31,8 @@ void	i8254_init(void);
 
 int	acquire_timer2(int mode);
 int	release_timer2(void);
-int	rtcin(int val);
+int	rtcin(int reg);
+void	writertc(int reg, unsigned char val);
 int	sysbeep(int pitch, int period);
 void	timer_restore(void);
 void	init_TSC(void);
diff --git a/sys/i386/isa/clock.c b/sys/i386/isa/clock.c
index 4b848c4..a67db31 100644
--- a/sys/i386/isa/clock.c
+++ b/sys/i386/isa/clock.c
@@ -438,7 +438,7 @@ rtcin(reg)
 	return (val);
 }
 
-static void
+void
 writertc(int reg, u_char val)
 {
 
@@ -938,99 +938,4 @@ static devclass_t attimer_devclass;
 DRIVER_MODULE(attimer, isa, attimer_driver, attimer_devclass, 0, 0);
 DRIVER_MODULE(attimer, acpi, attimer_driver, attimer_devclass, 0, 0);
 
-/*
- * Linux-style /dev/nvram driver
- *
- * cmos ram starts at bytes 14 through 128, for a total of 114 bytes.
- * bytes 16 through 31 are checksummed at byte 32.
- * Unlike Linux, you have to take care of the checksums yourself.
- * The driver exposes byte 14 as file offset 0.
- */
-
-#define NVRAM_FIRST	RTC_DIAG	/* 14 */
-#define NVRAM_LAST	128
-
-static d_open_t		nvram_open;
-static d_read_t		nvram_read;
-static d_write_t	nvram_write;
-
-static struct cdev *nvram_dev;
-
-static struct cdevsw nvram_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_flags =	D_NEEDGIANT,
-	.d_open =	nvram_open,
-	.d_read =	nvram_read,
-	.d_write =	nvram_write,
-	.d_name =	"nvram",
-};
-
-static int
-nvram_open(struct cdev *dev __unused, int flags, int fmt __unused,
-    struct thread *td)
-{
-	int error = 0;
-
-	if (flags & FWRITE)
-		error = securelevel_gt(td->td_ucred, 0);
-
-	return (error);
-}
-
-static int
-nvram_read(struct cdev *dev, struct uio *uio, int flags)
-{
-	int nv_off;
-	u_char v;
-	int error = 0;
-
-	while (uio->uio_resid > 0 && error == 0) {
-		nv_off = uio->uio_offset + NVRAM_FIRST;
-		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
-			return (0);	/* Signal EOF */
-		/* Single byte at a time */
-		v = rtcin(nv_off);
-		error = uiomove(&v, 1, uio);
-	}
-	return (error);
-
-}
-
-static int
-nvram_write(struct cdev *dev, struct uio *uio, int flags)
-{
-	int nv_off;
-	u_char v;
-	int error = 0;
-
-	while (uio->uio_resid > 0 && error == 0) {
-		nv_off = uio->uio_offset + NVRAM_FIRST;
-		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
-			return (0);	/* Signal EOF */
-		/* Single byte at a time */
-		error = uiomove(&v, 1, uio);
-		writertc(nv_off, v);
-	}
-	return (error);
-}
-
-static int
-nvram_modevent(module_t mod __unused, int type, void *data __unused)
-{
-	switch (type) {
-	case MOD_LOAD:
-		nvram_dev = make_dev(&nvram_cdevsw, 0,
-		    UID_ROOT, GID_KMEM, 0640, "nvram");
-		break;
-	case MOD_UNLOAD:
-	case MOD_SHUTDOWN:
-		destroy_dev(nvram_dev);
-		break;
-	default:
-		return (EOPNOTSUPP);
-	}
-	return (0);
-}
-DEV_MODULE(nvram, nvram_modevent, NULL);
-
 #endif /* DEV_ISA */
diff --git a/sys/isa/atrtc.c b/sys/isa/atrtc.c
index 4b848c4..a67db31 100644
--- a/sys/isa/atrtc.c
+++ b/sys/isa/atrtc.c
@@ -438,7 +438,7 @@ rtcin(reg)
 	return (val);
 }
 
-static void
+void
 writertc(int reg, u_char val)
 {
 
@@ -938,99 +938,4 @@ static devclass_t attimer_devclass;
 DRIVER_MODULE(attimer, isa, attimer_driver, attimer_devclass, 0, 0);
 DRIVER_MODULE(attimer, acpi, attimer_driver, attimer_devclass, 0, 0);
 
-/*
- * Linux-style /dev/nvram driver
- *
- * cmos ram starts at bytes 14 through 128, for a total of 114 bytes.
- * bytes 16 through 31 are checksummed at byte 32.
- * Unlike Linux, you have to take care of the checksums yourself.
- * The driver exposes byte 14 as file offset 0.
- */
-
-#define NVRAM_FIRST	RTC_DIAG	/* 14 */
-#define NVRAM_LAST	128
-
-static d_open_t		nvram_open;
-static d_read_t		nvram_read;
-static d_write_t	nvram_write;
-
-static struct cdev *nvram_dev;
-
-static struct cdevsw nvram_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_flags =	D_NEEDGIANT,
-	.d_open =	nvram_open,
-	.d_read =	nvram_read,
-	.d_write =	nvram_write,
-	.d_name =	"nvram",
-};
-
-static int
-nvram_open(struct cdev *dev __unused, int flags, int fmt __unused,
-    struct thread *td)
-{
-	int error = 0;
-
-	if (flags & FWRITE)
-		error = securelevel_gt(td->td_ucred, 0);
-
-	return (error);
-}
-
-static int
-nvram_read(struct cdev *dev, struct uio *uio, int flags)
-{
-	int nv_off;
-	u_char v;
-	int error = 0;
-
-	while (uio->uio_resid > 0 && error == 0) {
-		nv_off = uio->uio_offset + NVRAM_FIRST;
-		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
-			return (0);	/* Signal EOF */
-		/* Single byte at a time */
-		v = rtcin(nv_off);
-		error = uiomove(&v, 1, uio);
-	}
-	return (error);
-
-}
-
-static int
-nvram_write(struct cdev *dev, struct uio *uio, int flags)
-{
-	int nv_off;
-	u_char v;
-	int error = 0;
-
-	while (uio->uio_resid > 0 && error == 0) {
-		nv_off = uio->uio_offset + NVRAM_FIRST;
-		if (nv_off < NVRAM_FIRST || nv_off >= NVRAM_LAST)
-			return (0);	/* Signal EOF */
-		/* Single byte at a time */
-		error = uiomove(&v, 1, uio);
-		writertc(nv_off, v);
-	}
-	return (error);
-}
-
-static int
-nvram_modevent(module_t mod __unused, int type, void *data __unused)
-{
-	switch (type) {
-	case MOD_LOAD:
-		nvram_dev = make_dev(&nvram_cdevsw, 0,
-		    UID_ROOT, GID_KMEM, 0640, "nvram");
-		break;
-	case MOD_UNLOAD:
-	case MOD_SHUTDOWN:
-		destroy_dev(nvram_dev);
-		break;
-	default:
-		return (EOPNOTSUPP);
-	}
-	return (0);
-}
-DEV_MODULE(nvram, nvram_modevent, NULL);
-
 #endif /* DEV_ISA */
diff --git a/sys/modules/Makefile b/sys/modules/Makefile
index d8279ba..539031f 100644
--- a/sys/modules/Makefile
+++ b/sys/modules/Makefile
@@ -188,6 +188,7 @@ SUBDIR=	${_3dfx} \
 	ntfs_iconv \
 	nullfs \
 	${_nve} \
+	${_nvram} \
 	${_nwfs} \
 	${_nxge} \
 	${_oltr} \
@@ -202,7 +203,6 @@ SUBDIR=	${_3dfx} \
 	plip \
 	${_pmc} \
 	portalfs \
-	${_powermac_nvram} \
 	ppbus \
 	ppc \
 	ppi \
@@ -399,6 +399,7 @@ _mse=		mse
 _ncp=		ncp
 .endif
 _ncv=		ncv
+_nvram=		nvram
 _ndis=		ndis
 _nsp=		nsp
 .if ${MK_NCP} != "no"
@@ -519,6 +520,7 @@ _mly=		mly
 _ndis=		ndis
 _nfe=		nfe
 _nve=		nve
+_nvram=		nvram
 _nxge=		nxge
 _pccard=	pccard
 _rr232x=	rr232x
@@ -579,7 +581,7 @@ _ath_hal=	ath_hal
 _ath_rate_amrr=	ath_rate_amrr
 _ath_rate_onoe=	ath_rate_onoe
 _ath_rate_sample=ath_rate_sample
-_powermac_nvram=	powermac_nvram
+_nvram=		powermac_nvram
 _smbfs=		smbfs
 .endif
 
diff --git a/sys/modules/nvram/Makefile b/sys/modules/nvram/Makefile
new file mode 100644
index 0000000..7af468d
--- /dev/null
+++ b/sys/modules/nvram/Makefile
@@ -0,0 +1,8 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../dev/nvram
+
+KMOD=	nvram
+SRCS=	nvram.c
+
+.include <bsd.kmod.mk>