Add exrtc(4), a driver for the RTC found on Samsung Exynos SoCs.

2 files changed, 155 insertions, 1 deletions

diff --git a/sys/dev/fdt/exrtc.c b/sys/dev/fdt/exrtc.c
new file mode 100644
index 00000000000..0b54c236c57
--- /dev/null
+++ b/sys/dev/fdt/exrtc.c
@@ -0,0 +1,150 @@
+/*	$OpenBSD: exrtc.c,v 1.1 2017/03/11 00:11:47 kettenis Exp $	*/
+/*
+ * Copyright (c) 2017 Mark kettenis <kettenis@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/time.h>
+
+#include <machine/bus.h>
+#include <machine/fdt.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/fdt.h>
+
+#include <dev/clock_subr.h>
+
+extern todr_chip_handle_t todr_handle;
+
+#define RTCCTRL		0x40
+#define RTCCTRL_RTCEN	(1 << 0)
+
+#define RTCSEC		0x70
+#define RTCMIN		0x74
+#define RTCHOUR		0x78
+#define RTCDAY		0x7c
+#define RTCMON		0x84
+#define RTCYEAR		0x88
+
+#define HREAD4(sc, reg)							\
+	(bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg)))
+#define HWRITE4(sc, reg, val)						\
+	bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, (reg), (val))
+
+struct exrtc_softc {
+	struct device	sc_dev;
+	bus_space_tag_t		sc_iot;
+	bus_space_handle_t	sc_ioh;
+	struct todr_chip_handle sc_todr;
+};
+
+int	exrtc_match(struct device *, void *, void *);
+void	exrtc_attach(struct device *, struct device *, void *);
+
+struct cfattach exrtc_ca = {
+	sizeof(struct exrtc_softc), exrtc_match, exrtc_attach
+};
+
+struct cfdriver exrtc_cd = {
+	NULL, "exrtc", DV_DULL
+};
+
+int	exrtc_gettime(todr_chip_handle_t, struct timeval *);
+int	exrtc_settime(todr_chip_handle_t, struct timeval *);
+
+int
+exrtc_match(struct device *parent, void *match, void *aux)
+{
+	struct fdt_attach_args *faa = aux;
+
+	return OF_is_compatible(faa->fa_node, "samsung,s3c6410-rtc");
+}
+
+void
+exrtc_attach(struct device *parent, struct device *self, void *aux)
+{
+	struct exrtc_softc *sc = (struct exrtc_softc *)self;
+	struct fdt_attach_args *faa = aux;
+	struct clock_ymdhms dt;
+
+	sc->sc_iot = faa->fa_iot;
+
+	if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr,
+	    faa->fa_reg[0].size, 0, &sc->sc_ioh))
+		panic("%s: bus_space_map failed!", __func__);
+
+	printf("\n");
+
+	sc->sc_todr.cookie = sc;
+	sc->sc_todr.todr_gettime = exrtc_gettime;
+	sc->sc_todr.todr_settime = exrtc_settime;
+	todr_handle = &sc->sc_todr;
+}
+
+int
+exrtc_gettime(todr_chip_handle_t handle, struct timeval *tv)
+{
+	struct exrtc_softc *sc = handle->cookie;
+	struct clock_ymdhms dt;
+	int retried = 0;
+
+retry:
+	dt.dt_sec = FROMBCD(HREAD4(sc, RTCSEC));
+	dt.dt_min = FROMBCD(HREAD4(sc, RTCMIN));
+	dt.dt_hour = FROMBCD(HREAD4(sc, RTCHOUR));
+	dt.dt_day = FROMBCD(HREAD4(sc, RTCDAY));
+	dt.dt_mon = FROMBCD(HREAD4(sc, RTCMON));
+	dt.dt_year = FROMBCD(HREAD4(sc, RTCYEAR)) + 1900;
+
+	/* If the second counter rolled over, retry. */
+	if (dt.dt_sec > FROMBCD(HREAD4(sc, RTCSEC)) && !retried) {
+		retried = 1;
+		goto retry;
+	}
+
+	if (dt.dt_sec > 59 || dt.dt_min > 59 || dt.dt_hour > 23 ||
+	    dt.dt_day > 31 || dt.dt_day == 0 ||
+	    dt.dt_mon > 12 || dt.dt_mon == 0 ||
+	    dt.dt_year < POSIX_BASE_YEAR)
+		return 1;
+
+	tv->tv_sec = clock_ymdhms_to_secs(&dt);
+	tv->tv_usec = 0;
+	return 0;
+}
+
+int
+exrtc_settime(todr_chip_handle_t handle, struct timeval *tv)
+{
+	struct exrtc_softc *sc = handle->cookie;
+	struct clock_ymdhms dt;
+	uint32_t val;
+
+	clock_secs_to_ymdhms(tv->tv_sec, &dt);
+
+	HWRITE4(sc, RTCSEC, TOBCD(dt.dt_sec));
+	HWRITE4(sc, RTCMIN, TOBCD(dt.dt_min));
+	HWRITE4(sc, RTCHOUR, TOBCD(dt.dt_hour));
+	HWRITE4(sc, RTCDAY, TOBCD(dt.dt_day));
+	HWRITE4(sc, RTCMON, TOBCD(dt.dt_mon));
+	HWRITE4(sc, RTCYEAR, TOBCD(dt.dt_year - 1900));
+
+	val = HREAD4(sc, RTCCTRL);
+	HWRITE4(sc, RTCCTRL, val | RTCCTRL_RTCEN);
+
+	return 0;
+}
diff --git a/sys/dev/fdt/files.fdt b/sys/dev/fdt/files.fdt
index ce495179573..6e242f9a60c 100644
--- a/sys/dev/fdt/files.fdt
+++ b/sys/dev/fdt/files.fdt
@@ -1,4 +1,4 @@
-#	$OpenBSD: files.fdt,v 1.8 2017/03/09 20:04:21 kettenis Exp $
+#	$OpenBSD: files.fdt,v 1.9 2017/03/11 00:11:47 kettenis Exp $
 #
 # Config file and device description for machine-independent FDT code.
 # Included by ports that need it.
@@ -30,6 +30,10 @@ device	bcmdog
 attach	bcmdog at fdt
 file	dev/fdt/bcm2835_dog.c		bcmdog
 
+device	exrtc
+attach	exrtc at fdt
+file	dev/fdt/exrtc.c			exrtc
+
 # ARM PrimeCell PL031 Real-time clock
 device	plrtc
 attach	plrtc at fdt