Add device to access and modify Open Firmware NVRAM settings in

PowerPC-based Apple's machines and small utility to do it from
userland modelled after the similar utility in Darwin/OSX.

Only tested on 1.25GHz G4 Mac Mini.

MFC after:	1 month

2 files changed, 491 insertions, 0 deletions

diff --git a/sys/dev/powermac_nvram/powermac_nvram.c b/sys/dev/powermac_nvram/powermac_nvram.c
new file mode 100644
index 000000000000..e131d6a99484
--- /dev/null
+++ b/sys/dev/powermac_nvram/powermac_nvram.c
@@ -0,0 +1,423 @@
+/*
+ * Copyright (c) 2006 Maxim Sobolev <sobomax@FreeBSD.org>
+ * 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 ``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 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/module.h>
+#include <sys/bus.h>
+#include <sys/conf.h>
+#include <sys/kernel.h>
+#include <sys/uio.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_pci.h>
+
+#include <machine/bus.h>
+#include <machine/md_var.h>
+#include <machine/nexusvar.h>
+#include <machine/resource.h>
+
+#include <sys/rman.h>
+
+#include <powerpc/ofw/ofw_pci.h>
+#include <dev/powermac_nvram/powermac_nvramvar.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+/*
+ * Device interface.
+ */
+static int		powermac_nvram_probe(device_t);
+static int		powermac_nvram_attach(device_t);
+static int		powermac_nvram_detach(device_t);
+
+/* Helper functions */
+static int		powermac_nvram_check(void *data);
+static int		chrp_checksum(int sum, uint8_t *, uint8_t *);
+static uint32_t		adler_checksum(uint8_t *, int);
+static int		erase_bank(device_t, uint8_t *);
+static int		write_bank(device_t, uint8_t *, uint8_t *);
+
+/*
+ * Driver methods.
+ */
+static device_method_t	powermac_nvram_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		powermac_nvram_probe),
+	DEVMETHOD(device_attach,	powermac_nvram_attach),
+	DEVMETHOD(device_detach,	powermac_nvram_detach),
+
+	{ 0, 0 }
+};
+
+static driver_t	powermac_nvram_driver = {
+	"powermac_nvram",
+	powermac_nvram_methods,
+	sizeof(struct powermac_nvram_softc)
+};
+
+static devclass_t powermac_nvram_devclass;
+
+DRIVER_MODULE(powermac_nvram, nexus, powermac_nvram_driver, powermac_nvram_devclass, 0, 0);
+
+/*
+ * Cdev methods.
+ */
+
+#define	NVRAM_UNIT(dev)		minor(dev)
+#define	NVRAM_SOFTC(unit)	((struct powermac_nvram_softc *) \
+     devclass_get_softc(powermac_nvram_devclass, unit))
+
+static	d_open_t	powermac_nvram_open;
+static	d_close_t	powermac_nvram_close;
+static	d_read_t	powermac_nvram_read;
+static	d_write_t	powermac_nvram_write;
+
+static struct cdevsw powermac_nvram_cdevsw = {
+	.d_version =	D_VERSION,
+	.d_flags =	D_NEEDGIANT,
+	.d_open =	powermac_nvram_open,
+	.d_close =	powermac_nvram_close,
+	.d_read =	powermac_nvram_read,
+	.d_write =	powermac_nvram_write,
+	.d_name =	"powermac_nvram",
+};
+
+static int
+powermac_nvram_probe(device_t dev)
+{
+	char	*type, *compatible;
+
+	type = nexus_get_device_type(dev);
+	compatible = nexus_get_compatible(dev);
+
+	if (type == NULL || compatible == NULL)
+		return ENXIO;
+
+	if (strcmp(type, "nvram") != 0 || strcmp(compatible, "amd-0137") != 0)
+		return ENXIO;
+
+	device_set_desc(dev, "Apple NVRAM");
+	return 0;
+}
+
+static int
+powermac_nvram_attach(device_t dev)
+{
+	struct powermac_nvram_softc *sc;
+	phandle_t node;
+	u_int32_t reg[2];
+	int gen0, gen1;
+
+	node = nexus_get_node(dev);
+	sc = device_get_softc(dev);
+
+	if (OF_getprop(node, "reg", reg, sizeof(reg)) < 8)
+		return ENXIO;
+
+	sc->sc_dev = dev;
+	sc->sc_node = node;
+
+	sc->sc_bank0 = (vm_offset_t)pmap_mapdev(reg[0], NVRAM_SIZE * 2);
+	sc->sc_bank1 = sc->sc_bank0 + NVRAM_SIZE;
+
+	gen0 = powermac_nvram_check((void *)sc->sc_bank0);
+	gen1 = powermac_nvram_check((void *)sc->sc_bank1);
+
+	if (gen0 == -1 && gen1 == -1) {
+		if ((void *)sc->sc_bank0 != NULL)
+			pmap_unmapdev(sc->sc_bank0, NVRAM_SIZE * 2);
+		device_printf(dev, "both banks appear to be corrupt\n");
+		return ENXIO;
+	}
+	device_printf(dev, "bank0 generation %d, bank1 generation %d\n",
+	    gen0, gen1);
+
+	sc->sc_bank = (gen0 > gen1) ? sc->sc_bank0 : sc->sc_bank1;
+	bcopy((void *)sc->sc_bank, (void *)sc->sc_data, NVRAM_SIZE);
+
+	sc->sc_cdev = make_dev(&powermac_nvram_cdevsw, 0, 0, 0, 0600,
+	    "powermac_nvram");
+
+	return 0;
+}
+
+static int
+powermac_nvram_detach(device_t dev)
+{
+	struct powermac_nvram_softc *sc;
+
+	sc = device_get_softc(dev);
+
+	if ((void *)sc->sc_bank0 != NULL)
+		pmap_unmapdev(sc->sc_bank0, NVRAM_SIZE * 2);
+
+	if (sc->sc_cdev != NULL)
+		destroy_dev(sc->sc_cdev);
+	
+	return 0;
+}
+
+static int
+powermac_nvram_open(struct cdev *dev, int flags, int fmt, struct thread *td)
+{
+	struct powermac_nvram_softc *sc;
+
+	sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
+	if (sc->sc_isopen)
+		return EBUSY;
+	sc->sc_isopen = 1;
+	sc->sc_rpos = sc->sc_wpos = 0;
+	return 0;
+}
+
+static int
+powermac_nvram_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
+{
+	struct powermac_nvram_softc *sc;
+	struct core99_header *header;
+	vm_offset_t bank;
+
+	sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
+
+	if (sc->sc_wpos != sizeof(sc->sc_data)) {
+		/* Short write, restore in-memory copy */
+		bcopy((void *)sc->sc_bank, (void *)sc->sc_data, NVRAM_SIZE);
+		sc->sc_isopen = 0;
+		return 0;
+	}
+
+	header = (struct core99_header *)sc->sc_data;
+
+	header->generation = ((struct core99_header *)sc->sc_bank)->generation;
+	header->generation++;
+	header->chrp_header.signature = CORE99_SIGNATURE;
+
+	header->adler_checksum =
+	    adler_checksum((uint8_t *)&(header->generation),
+	    NVRAM_SIZE - offsetof(struct core99_header, generation));
+	header->chrp_header.chrp_checksum = chrp_checksum(header->chrp_header.signature,
+	    (uint8_t *)&(header->chrp_header.length),
+	    (uint8_t *)&(header->adler_checksum));
+
+	bank = (sc->sc_bank == sc->sc_bank0) ? sc->sc_bank1 : sc->sc_bank0;
+	if (erase_bank(sc->sc_dev, (uint8_t *)bank) != 0 ||
+	    write_bank(sc->sc_dev, (uint8_t *)bank, sc->sc_data) != 0) {
+		sc->sc_isopen = 0;
+		return ENOSPC;
+	}
+	sc->sc_bank = bank;
+	sc->sc_isopen = 0;
+	return 0;
+}
+
+static int
+powermac_nvram_read(struct cdev *dev, struct uio *uio, int ioflag)
+{
+	int rv, amnt, data_available;
+	struct powermac_nvram_softc *sc;
+
+	sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
+
+	rv = 0;
+	while (uio->uio_resid > 0) {
+		data_available = sizeof(sc->sc_data) - sc->sc_rpos;
+		if (data_available > 0) {
+			amnt = MIN(uio->uio_resid, data_available);
+			rv = uiomove((void *)(sc->sc_data + sc->sc_rpos),
+			    amnt, uio);
+			if (rv != 0)
+				break;
+			sc->sc_rpos += amnt;
+		} else {
+			break;
+		}
+	}
+	return rv;
+}
+
+static int
+powermac_nvram_write(struct cdev *dev, struct uio *uio, int ioflag)
+{
+	int rv, amnt, data_available;
+	struct powermac_nvram_softc *sc;
+
+	sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
+
+	if (sc->sc_wpos >= sizeof(sc->sc_data))
+		return EINVAL;
+
+	rv = 0;
+	while (uio->uio_resid > 0) {
+		data_available = sizeof(sc->sc_data) - sc->sc_wpos;
+		if (data_available > 0) {
+			amnt = MIN(uio->uio_resid, data_available);
+			rv = uiomove((void *)(sc->sc_data + sc->sc_wpos),
+			    amnt, uio);
+			if (rv != 0)
+				break;
+			sc->sc_wpos += amnt;
+		} else {
+			break;
+		}
+	}
+	return rv;
+}
+
+static int
+powermac_nvram_check(void *data)
+{
+	struct core99_header *header;
+
+	header = (struct core99_header *)data;
+
+	if (header->chrp_header.signature != CORE99_SIGNATURE)
+		return -1;
+	if (header->chrp_header.chrp_checksum !=
+	    chrp_checksum(header->chrp_header.signature,
+	    (uint8_t *)&(header->chrp_header.length),
+	    (uint8_t *)&(header->adler_checksum)))
+		return -1;
+	if (header->adler_checksum !=
+	    adler_checksum((uint8_t *)&(header->generation),
+	    NVRAM_SIZE - offsetof(struct core99_header, generation)))
+		return -1;
+	return header->generation;
+}
+
+static int
+chrp_checksum(int sum, uint8_t *data, uint8_t *end)
+{
+
+	for (; data < end; data++)
+		sum += data[0];
+	while (sum > 0xff)
+		sum = (sum & 0xff) + (sum >> 8);
+	return sum;
+}
+
+static uint32_t
+adler_checksum(uint8_t *data, int len)
+{
+	uint32_t low, high;
+	int i;
+
+	low = 1;
+	high = 0;
+	for (i = 0; i < len; i++) {
+		if ((i % 5000) == 0) {
+			high %= 65521UL;
+			high %= 65521UL;
+		}
+		low += data[i];
+		high += low;
+	}
+	low %= 65521UL;
+	high %= 65521UL;
+
+	return (high << 16) | low;
+}
+
+#define	OUTB_DELAY(a, v)	outb(a, v); DELAY(1);
+
+static int
+wait_operation_complete(uint8_t *bank)
+{
+	int i;
+
+	for (i = 1000000; i != 0; i--)
+		if ((inb(bank) ^ inb(bank)) == 0)
+			return 0;
+	return -1;
+}
+
+static int
+erase_bank(device_t dev, uint8_t *bank)
+{
+	unsigned int i;
+
+	/* Unlock 1 */
+	OUTB_DELAY(bank + 0x555, 0xaa);
+	/* Unlock 2 */
+	OUTB_DELAY(bank + 0x2aa, 0x55);
+
+	/* Sector-Erase */
+	OUTB_DELAY(bank + 0x555, 0x80);
+	OUTB_DELAY(bank + 0x555, 0xaa);
+	OUTB_DELAY(bank + 0x2aa, 0x55);
+	OUTB_DELAY(bank, 0x30);
+
+	if (wait_operation_complete(bank) != 0) {
+		device_printf(dev, "flash erase timeout\n");
+		return -1;
+	}
+
+	/* Reset */
+	OUTB_DELAY(bank, 0xf0);
+
+	for (i = 0; i < NVRAM_SIZE; i++) {
+		if (bank[i] != 0xff) {
+			device_printf(dev, "flash erase has failed\n");
+			return -1;
+		}
+	}
+	return 0;
+}
+
+static int
+write_bank(device_t dev, uint8_t *bank, uint8_t *data)
+{
+	unsigned int i;
+
+	for (i = 0; i < NVRAM_SIZE; i++) {
+		/* Unlock 1 */
+		OUTB_DELAY(bank + 0x555, 0xaa);
+		/* Unlock 2 */
+		OUTB_DELAY(bank + 0x2aa, 0x55);
+
+		/* Write single word */
+		OUTB_DELAY(bank + 0x555, 0xa0);
+		OUTB_DELAY(bank + i, data[i]);
+		if (wait_operation_complete(bank) != 0) {
+			device_printf(dev, "flash write timeout\n");
+			return -1;
+		}
+	}
+
+	/* Reset */
+	OUTB_DELAY(bank, 0xf0);
+
+	for (i = 0; i < NVRAM_SIZE; i++) {
+		if (bank[i] != data[i]) {
+			device_printf(dev, "flash write has failed\n");
+			return -1;
+		}
+	}
+	return 0;
+}
diff --git a/sys/dev/powermac_nvram/powermac_nvramvar.h b/sys/dev/powermac_nvram/powermac_nvramvar.h
new file mode 100644
index 000000000000..6f4fb26e8990
--- /dev/null
+++ b/sys/dev/powermac_nvram/powermac_nvramvar.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2006 Maxim Sobolev <sobomax@FreeBSD.org>
+ * 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 ``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 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef	_POWERPC_POWERMAC_POWERMAC_NVRAMVAR_H_
+#define	_POWERPC_POWERMAC_POWERMAC_NVRAMVAR_H_
+
+#define	NVRAM_SIZE		0x2000
+
+#define	CORE99_SIGNATURE	0x5a
+
+#ifdef _KERNEL
+
+struct powermac_nvram_softc {
+	device_t		sc_dev;
+	phandle_t		sc_node;
+	vm_offset_t		sc_bank;
+	vm_offset_t		sc_bank0;
+	vm_offset_t		sc_bank1;
+	uint8_t			sc_data[NVRAM_SIZE];
+
+	struct cdev *		sc_cdev;
+	int			sc_isopen;
+	int			sc_rpos;
+	int			sc_wpos;
+};
+
+#endif /* _KERNEL */
+
+struct chrp_header {
+	uint8_t			signature;
+	uint8_t			chrp_checksum;
+	uint16_t		length;
+	char			name[12];
+};
+
+struct core99_header {
+	struct chrp_header	chrp_header;
+	uint32_t		adler_checksum;
+	uint32_t		generation;
+	uint32_t		reserved[2];
+};
+
+#endif  /* _POWERPC_POWERMAC_POWERMAC_NVRAMVAR_H_ */