Add bcmgpio(4). For now this driver only provides pinctrl functionality.

Actual gpio support (possibly including gpio(4) support) will come later.

ok jsg@

2 files changed, 204 insertions, 1 deletions

diff --git a/sys/dev/fdt/bcm2835_gpio.c b/sys/dev/fdt/bcm2835_gpio.c
new file mode 100644
index 00000000000..4d9d0ab3426
--- /dev/null
+++ b/sys/dev/fdt/bcm2835_gpio.c
@@ -0,0 +1,199 @@
+/*	$OpenBSD: bcm2835_gpio.c,v 1.1 2020/04/24 09:52:43 kettenis Exp $	*/
+/*
+ * Copyright (c) 2020 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/device.h>
+#include <sys/malloc.h>
+#include <sys/systm.h>
+
+#include <machine/bus.h>
+#include <machine/fdt.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_pinctrl.h>
+#include <dev/ofw/fdt.h>
+
+/* Registers */
+#define GPFSEL(n)		(0x00 + ((n) * 4))
+#define  GPFSEL_MASK		0x7
+#define  GPFSEL_GPIO_IN		0x0
+#define  GPFSEL_GPIO_OUT	0x1
+#define  GPFSEL_ALT0		0x4
+#define  GPFSEL_ALT1		0x5
+#define  GPFSEL_ALT2		0x6
+#define  GPFSEL_ALT3		0x7
+#define  GPFSEL_ALT4		0x3
+#define  GPFSEL_ALT5		0x2
+#define GPPUD			0x94
+#define  GPPUD_PUD		0x3
+#define  GPPUD_PUD_OFF		0x0
+#define  GPPUD_PUD_DOWN		0x1
+#define  GPPUD_PUD_UP		0x2
+#define GPPUDCLK(n)		(0x98 + ((n) * 4))
+#define GPPULL(n)		(0xe4 + ((n) * 4))
+#define  GPPULL_MASK		0x3
+
+#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 bcmgpio_softc {
+	struct device		sc_dev;
+	bus_space_tag_t		sc_iot;
+	bus_space_handle_t	sc_ioh;
+
+	void	(*sc_config_pull)(struct bcmgpio_softc *, int, int);
+};
+
+int	bcmgpio_match(struct device *, void *, void *);
+void	bcmgpio_attach(struct device *, struct device *, void *);
+
+struct cfattach	bcmgpio_ca = {
+	sizeof (struct bcmgpio_softc), bcmgpio_match, bcmgpio_attach
+};
+
+struct cfdriver bcmgpio_cd = {
+	NULL, "bcmgpio", DV_DULL
+};
+
+void	bcm2711_config_pull(struct bcmgpio_softc *, int, int);
+void	bcm2835_config_pull(struct bcmgpio_softc *, int, int);
+int	bcmgpio_pinctrl(uint32_t, void *);
+
+int
+bcmgpio_match(struct device *parent, void *match, void *aux)
+{
+	struct fdt_attach_args *faa = aux;
+
+	return (OF_is_compatible(faa->fa_node, "brcm,bcm2711-gpio") ||
+	    OF_is_compatible(faa->fa_node, "brcm,bcm2835-gpio"));
+}
+
+void
+bcmgpio_attach(struct device *parent, struct device *self, void *aux)
+{
+	struct bcmgpio_softc *sc = (struct bcmgpio_softc *)self;
+	struct fdt_attach_args *faa = aux;
+
+	if (faa->fa_nreg < 1) {
+		printf(": no registers\n");
+		return;
+	}
+
+	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)) {
+		printf(": can't map registers\n");
+		return;
+	}
+
+	printf("\n");
+
+	if (OF_is_compatible(faa->fa_node, "brcm,bcm2711-gpio"))
+	    sc->sc_config_pull = bcm2711_config_pull;
+	else
+	    sc->sc_config_pull = bcm2835_config_pull;
+
+	pinctrl_register(faa->fa_node, bcmgpio_pinctrl, sc);
+}
+
+void
+bcmgpio_config_func(struct bcmgpio_softc *sc, int pin, int func)
+{
+	int reg = (pin / 10);
+	int shift = (pin % 10) * 3;
+	uint32_t val;
+	
+	val = HREAD4(sc, GPFSEL(reg));
+	val &= ~(GPFSEL_MASK << shift);
+	HWRITE4(sc, GPFSEL(reg), val);
+	val |= ((func & GPFSEL_MASK) << shift);
+	HWRITE4(sc, GPFSEL(reg), val);
+}
+
+void
+bcm2711_config_pull(struct bcmgpio_softc *sc, int pin, int pull)
+{
+	int reg = (pin / 16);
+	int shift = (pin % 16) * 2;
+	uint32_t val;
+
+	val = HREAD4(sc, GPPULL(reg));
+	val &= ~(GPPULL_MASK << shift);
+	pull = ((pull & 1) << 1) | ((pull & 2) >> 1);
+	val |= (pull << shift);
+	HWRITE4(sc, GPPULL(reg), val);
+}
+
+void
+bcm2835_config_pull(struct bcmgpio_softc *sc, int pin, int pull)
+{
+	int reg = (pin / 32);
+	int shift = (pin % 32);
+
+	HWRITE4(sc, GPPUD, pull & GPPUD_PUD);
+	delay(1);
+	HWRITE4(sc, GPPUDCLK(reg), 1 << shift);
+	delay(1);
+	HWRITE4(sc, GPPUDCLK(reg), 0);
+}
+
+int
+bcmgpio_pinctrl(uint32_t phandle, void *cookie)
+{
+	struct bcmgpio_softc *sc = cookie;
+	uint32_t *pins, *pull = NULL;
+	int len, plen = 0;
+	int node, i;
+	int func;
+
+	node = OF_getnodebyphandle(phandle);
+	if (node == 0)
+		return -1;
+
+	len = OF_getproplen(node, "brcm,pins");
+	if (len <= 0)
+		return -1;
+
+	pins = malloc(len, M_TEMP, M_WAITOK);
+	if (OF_getpropintarray(node, "brcm,pins", pins, len) != len)
+		goto fail;
+	func = OF_getpropint(node, "brcm,function", -1);
+
+	plen = OF_getproplen(node, "brcm,pull");
+	if (plen > 0) {
+		pull = malloc(len, M_TEMP, M_WAITOK);
+		if (OF_getpropintarray(node, "brcm,pull", pull, plen) != plen)
+			goto fail;
+	}
+
+	for (i = 0; i < len / sizeof(uint32_t); i++) {
+		bcmgpio_config_func(sc, pins[i], func);
+		if (i < plen / sizeof(uint32_t))
+			sc->sc_config_pull(sc, pins[i], pull[i]);
+	}
+
+	free(pull, M_TEMP, plen);
+	free(pins, M_TEMP, len);
+	return 0;
+
+fail:
+	free(pull, M_TEMP, plen);
+	free(pins, M_TEMP, len);
+	return -1;
+}
diff --git a/sys/dev/fdt/files.fdt b/sys/dev/fdt/files.fdt
index a9b4082a944..f0b41a72c5e 100644
--- a/sys/dev/fdt/files.fdt
+++ b/sys/dev/fdt/files.fdt
@@ -1,4 +1,4 @@
-#	$OpenBSD: files.fdt,v 1.125 2020/04/23 22:14:49 patrick Exp $
+#	$OpenBSD: files.fdt,v 1.126 2020/04/24 09:52:43 kettenis Exp $
 #
 # Config file and device description for machine-independent FDT code.
 # Included by ports that need it.
@@ -93,6 +93,10 @@ device	bcmdog
 attach	bcmdog at fdt
 file	dev/fdt/bcm2835_dog.c		bcmdog
 
+device	bcmgpio
+attach	bcmgpio at fdt
+file	dev/fdt/bcm2835_gpio.c		bcmgpio
+
 device	bcmirng
 attach	bcmirng at fdt
 file	dev/fdt/bcm2711_rng.c		bcmirng