bcm2835_gpio: Handle BCM2711 pin configuration

Add support for GPIO internal pull up/down configuration on RPi4 family.

BCM2711 SoC on 4th generation Raspberry Pi changed the way to configure
its GPIO pins' internal pull up/down resistors. NetBSD already have
support for this change, and port it to FreeBSD is trivial.

This patch, based on the NetBSD commit adds the appropriate method for
BCM2711 and now we can properly configure the GPIO pins' pull status.

PR:		256372
Reviewed by:	mhorne
Obtained from:	NetBSD bb88cfa64ad8
Pull Request:	https://github.com/freebsd/freebsd-src/pull/746

1 files changed, 61 insertions, 20 deletions

diff --git a/sys/arm/broadcom/bcm2835/bcm2835_gpio.c b/sys/arm/broadcom/bcm2835/bcm2835_gpio.c
index d6e04a215ee1..8fc1299ce0d0 100644
--- a/sys/arm/broadcom/bcm2835/bcm2835_gpio.c
+++ b/sys/arm/broadcom/bcm2835/bcm2835_gpio.c
@@ -64,8 +64,10 @@ __FBSDID("$FreeBSD$");
 #endif
 
 #define	BCM_GPIO_IRQS		4
-#define	BCM_GPIO_PINS		54
 #define	BCM_GPIO_PINS_PER_BANK	32
+#define	BCM2835_GPIO_PINS	54
+#define	BCM2711_GPIO_PINS	58
+#define	BCM_GPIO_PINS		BCM2711_GPIO_PINS
 
 #define	BCM_GPIO_DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT |	\
     GPIO_PIN_PULLUP | GPIO_PIN_PULLDOWN | GPIO_INTR_LEVEL_LOW |		\
@@ -85,6 +87,10 @@ __FBSDID("$FreeBSD$");
 #define	BCM2835_PUD_DOWN	1
 #define	BCM2835_PUD_UP		2
 
+#define	BCM2711_PUD_OFF		0
+#define	BCM2711_PUD_DOWN	2
+#define	BCM2711_PUD_UP		1
+
 static struct resource_spec bcm_gpio_res_spec[] = {
 	{ SYS_RES_MEMORY, 0, RF_ACTIVE },
 	{ SYS_RES_IRQ, 0, RF_ACTIVE },	/* bank 0 interrupt */
@@ -112,6 +118,8 @@ struct bcm_gpio_softc {
 	bus_space_tag_t		sc_bst;
 	bus_space_handle_t	sc_bsh;
 	void *			sc_intrhand[BCM_GPIO_IRQS];
+	bool			sc_is2711;
+	u_int			sc_maxpins;
 	int			sc_gpio_npins;
 	int			sc_ro_npins;
 	int			sc_ro_pins[BCM_GPIO_PINS];
@@ -151,8 +159,13 @@ enum bcm_gpio_pud {
 #define	BCM_GPIO_GPLEN(_bank)	(0x70 + _bank * 4)	/* Low Level irq */
 #define	BCM_GPIO_GPAREN(_bank)	(0x7c + _bank * 4)	/* Async Rising Edge */
 #define	BCM_GPIO_GPAFEN(_bank)	(0x88 + _bank * 4)	/* Async Falling Egde */
-#define	BCM_GPIO_GPPUD(_bank)	(0x94)			/* Pin Pull up/down */
-#define	BCM_GPIO_GPPUDCLK(_bank) (0x98 + _bank * 4)	/* Pin Pull up clock */
+#define	BCM2835_GPIO_GPPUD(_bank) (0x94)		/* Pin Pull up/down */
+#define	BCM2835_GPIO_GPPUDCLK(_bank) (0x98 + _bank * 4)	/* Pin Pull up clock */
+
+#define	BCM2711_GPIO_GPPUD(x)	(0x0e4 + (x) * sizeof(uint32_t)) /* Pin Pull up/down */
+#define	BCM2711_GPIO_MASK	(0x3)
+#define	BCM2711_GPIO_SHIFT(n)	(((n) % 16) * 2)
+#define	BCM2711_GPIO_REGID(n)	((n) / 16)
 
 static struct ofw_compat_data compat_data[] = {
 	{"broadcom,bcm2835-gpio",	1},
@@ -289,16 +302,39 @@ bcm_gpio_set_function(struct bcm_gpio_softc *sc, uint32_t pin, uint32_t f)
 static void
 bcm_gpio_set_pud(struct bcm_gpio_softc *sc, uint32_t pin, uint32_t state)
 {
-	uint32_t bank;
-
 	/* Must be called with lock held. */
 	BCM_GPIO_LOCK_ASSERT(sc);
 
-	bank = BCM_GPIO_BANK(pin);
-	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUD(0), state);
-	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUDCLK(bank), BCM_GPIO_MASK(pin));
-	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUD(0), 0);
-	BCM_GPIO_WRITE(sc, BCM_GPIO_GPPUDCLK(bank), 0);
+	if (sc->sc_is2711) { /* BCM2711 */
+		u_int regid = BCM2711_GPIO_REGID(pin);
+		u_int shift = BCM2711_GPIO_SHIFT(pin);
+		uint32_t reg;
+
+		switch (state) {
+		case BCM2835_PUD_OFF:
+			state = BCM2711_PUD_OFF;
+			break;
+		case BCM2835_PUD_DOWN:
+			state = BCM2711_PUD_DOWN;
+			break;
+		case BCM2835_PUD_UP:
+			state = BCM2711_PUD_UP;
+			break;
+		}
+
+		reg = BCM_GPIO_READ(sc, BCM2711_GPIO_GPPUD(regid));
+		reg &= ~(BCM2711_GPIO_MASK << shift);
+		reg |= (state << shift);
+		BCM_GPIO_WRITE(sc, BCM2711_GPIO_GPPUD(regid), reg);
+	} else { /* BCM2835 */
+		uint32_t bank;
+
+		bank = BCM_GPIO_BANK(pin);
+		BCM_GPIO_WRITE(sc, BCM2835_GPIO_GPPUD(0), state);
+		BCM_GPIO_WRITE(sc, BCM2835_GPIO_GPPUDCLK(bank), BCM_GPIO_MASK(pin));
+		BCM_GPIO_WRITE(sc, BCM2835_GPIO_GPPUD(0), 0);
+		BCM_GPIO_WRITE(sc, BCM2835_GPIO_GPPUDCLK(bank), 0);
+	}
 }
 
 static void
@@ -376,8 +412,10 @@ bcm_gpio_get_bus(device_t dev)
 static int
 bcm_gpio_pin_max(device_t dev, int *maxpin)
 {
+	struct bcm_gpio_softc *sc;
 
-	*maxpin = BCM_GPIO_PINS - 1;
+	sc = device_get_softc(dev);
+	*maxpin = sc->sc_maxpins - 1;
 	return (0);
 }
 
@@ -770,16 +808,19 @@ bcm_gpio_attach(device_t dev)
 	}
 	sc->sc_bst = rman_get_bustag(sc->sc_res[0]);
 	sc->sc_bsh = rman_get_bushandle(sc->sc_res[0]);
-	/* Setup the GPIO interrupt handler. */
-	if (bcm_gpio_intr_attach(dev)) {
-		device_printf(dev, "unable to setup the gpio irq handler\n");
-		goto fail;
-	}
 	/* Find our node. */
 	gpio = ofw_bus_get_node(sc->sc_dev);
 	if (!OF_hasprop(gpio, "gpio-controller"))
 		/* Node is not a GPIO controller. */
 		goto fail;
+	/* Guess I'm BCM2711 or not. */
+	sc->sc_is2711 = ofw_bus_node_is_compatible(gpio, "brcm,bcm2711-gpio");
+	sc->sc_maxpins = sc->sc_is2711 ? BCM2711_GPIO_PINS : BCM2835_GPIO_PINS;
+	/* Setup the GPIO interrupt handler. */
+	if (bcm_gpio_intr_attach(dev)) {
+		device_printf(dev, "unable to setup the gpio irq handler\n");
+		goto fail;
+	}
 	/*
 	 * Find the read-only pins.  These are pins we never touch or bad
 	 * things could happen.
@@ -787,7 +828,7 @@ bcm_gpio_attach(device_t dev)
 	if (bcm_gpio_get_reserved_pins(sc) == -1)
 		goto fail;
 	/* Initialize the software controlled pins. */
-	for (i = 0, j = 0; j < BCM_GPIO_PINS; j++) {
+	for (i = 0, j = 0; j < sc->sc_maxpins; j++) {
 		snprintf(sc->sc_gpio_pins[i].gp_name, GPIOMAXNAME,
 		    "pin %d", j);
 		func = bcm_gpio_get_function(sc, j);
@@ -956,7 +997,7 @@ bcm_gpio_pic_attach(struct bcm_gpio_softc *sc)
 	const char *name;
 
 	name = device_get_nameunit(sc->sc_dev);
-	for (irq = 0; irq < BCM_GPIO_PINS; irq++) {
+	for (irq = 0; irq < sc->sc_maxpins; irq++) {
 		sc->sc_isrcs[irq].bgi_irq = irq;
 		sc->sc_isrcs[irq].bgi_mask = BCM_GPIO_MASK(irq);
 		sc->sc_isrcs[irq].bgi_mode = GPIO_INTR_CONFORM;
@@ -1044,7 +1085,7 @@ bcm_gpio_pic_map_fdt(struct bcm_gpio_softc *sc, struct intr_map_data_fdt *daf,
 		return (EINVAL);
 
 	irq = daf->cells[0];
-	if (irq >= BCM_GPIO_PINS || bcm_gpio_pin_is_ro(sc, irq))
+	if (irq >= sc->sc_maxpins || bcm_gpio_pin_is_ro(sc, irq))
 		return (EINVAL);
 
 	/* Only reasonable modes are supported. */
@@ -1075,7 +1116,7 @@ bcm_gpio_pic_map_gpio(struct bcm_gpio_softc *sc, struct intr_map_data_gpio *dag,
 	uint32_t mode;
 
 	irq = dag->gpio_pin_num;
-	if (irq >= BCM_GPIO_PINS || bcm_gpio_pin_is_ro(sc, irq))
+	if (irq >= sc->sc_maxpins || bcm_gpio_pin_is_ro(sc, irq))
 		return (EINVAL);
 
 	mode = dag->gpio_intr_mode;