svn commit: r328257 - in head/sys: arm/broadcom/bcm2835 dts/arm modules

Poul-Henning Kamp phk at FreeBSD.org
Mon Jan 22 07:10:32 UTC 2018


Author: phk
Date: Mon Jan 22 07:10:30 2018
New Revision: 328257
URL: https://svnweb.freebsd.org/changeset/base/328257

Log:
  Add a skeleton Clock Manager for RPi2/3, and use that from pwm
  instead of frobbing the registers directly.
  
  As a hack the bcm2835_pwm kmod presently ignores the 'status="disabled"'
  in the RPI3 DTB, assuming that if you load the kld you probably
  want the PWM to work.

Added:
  head/sys/arm/broadcom/bcm2835/bcm2835_clkman.c   (contents, props changed)
  head/sys/arm/broadcom/bcm2835/bcm2835_clkman.h   (contents, props changed)
Modified:
  head/sys/arm/broadcom/bcm2835/bcm2835_pwm.c
  head/sys/dts/arm/bcm2836.dtsi
  head/sys/modules/Makefile

Added: head/sys/arm/broadcom/bcm2835/bcm2835_clkman.c
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/arm/broadcom/bcm2835/bcm2835_clkman.c	Mon Jan 22 07:10:30 2018	(r328257)
@@ -0,0 +1,212 @@
+/*-
+ * Copyright (C) 2013-2015 Daisuke Aoyama <aoyama at peach.ne.jp>
+ * 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.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+#include <sys/cpu.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/rman.h>
+#include <sys/sema.h>
+#include <sys/sysctl.h>
+
+#include <machine/bus.h>
+#include <machine/cpu.h>
+
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+
+#include <arm/broadcom/bcm2835/bcm2835_clkman.h>
+
+static struct ofw_compat_data compat_data[] = {
+	{"brcm,bcm2835-cprman",		1},
+	{"broadcom,bcm2835-cprman",	1},
+	{NULL,				0}
+};
+
+struct bcm2835_clkman_softc {
+	device_t		sc_dev;
+
+	struct resource *	sc_m_res;
+	bus_space_tag_t		sc_m_bst;
+	bus_space_handle_t	sc_m_bsh;
+};
+
+#define BCM_CLKMAN_WRITE(_sc, _off, _val)              \
+    bus_space_write_4(_sc->sc_m_bst, _sc->sc_m_bsh, _off, _val)
+#define BCM_CLKMAN_READ(_sc, _off)                     \
+    bus_space_read_4(_sc->sc_m_bst, _sc->sc_m_bsh, _off)
+
+#define W_CMCLK(_sc, unit, _val) BCM_CLKMAN_WRITE(_sc, unit, 0x5a000000 | (_val))
+#define R_CMCLK(_sc, unit) BCM_CLKMAN_READ(_sc, unit)
+#define W_CMDIV(_sc, unit, _val) BCM_CLKMAN_WRITE(_sc, (unit) + 4, 0x5a000000 | (_val))
+#define R_CMDIV(_sc,  unit) BCM_CLKMAN_READ(_sc, (unit) + 4)
+
+static int
+bcm2835_clkman_probe(device_t dev)
+{
+
+	if (!ofw_bus_status_okay(dev))
+		return (ENXIO);
+
+	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
+		return (ENXIO);
+
+	device_set_desc(dev, "BCM283x Clock Manager");
+
+	return (BUS_PROBE_DEFAULT);
+}
+
+static int
+bcm2835_clkman_attach(device_t dev)
+{
+	struct bcm2835_clkman_softc *sc;
+	int rid;
+
+	if (device_get_unit(dev) != 0) {
+		device_printf(dev, "only one clk manager supported\n");
+		return (ENXIO);
+	}
+
+	sc = device_get_softc(dev);
+	sc->sc_dev = dev;
+
+	rid = 0;
+	sc->sc_m_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
+	    RF_ACTIVE);
+	if (!sc->sc_m_res) {
+		device_printf(dev, "cannot allocate memory window\n");
+		return (ENXIO);
+	}
+
+	sc->sc_m_bst = rman_get_bustag(sc->sc_m_res);
+	sc->sc_m_bsh = rman_get_bushandle(sc->sc_m_res);
+
+	return (bus_generic_attach(dev));
+}
+
+uint32_t
+bcm2835_clkman_set_frequency(device_t dev, uint32_t unit, uint32_t hz)
+{
+	struct bcm2835_clkman_softc *sc;
+	int i;
+	uint32_t u;
+
+	sc = device_get_softc(dev);
+
+	if (unit != BCM_PWM_CLKSRC) {
+		device_printf(sc->sc_dev,
+		    "Unsupported unit 0x%x", unit);
+		return (0);
+	}
+
+	W_CMCLK(sc, unit, 6);
+	for (i = 0; i < 10; i++) {
+		u = R_CMCLK(sc, unit);
+		if (!(u&0x80))
+			break;
+		DELAY(1000);
+	}
+	if (u & 0x80) {
+		device_printf(sc->sc_dev,
+		    "Failed to stop clock for unit 0x%x", unit);
+		return (0);
+	}
+	if (hz == 0)
+		return (0);
+
+	u = 500000000/hz;
+	if (u < 4) {
+		device_printf(sc->sc_dev,
+		    "Frequency too high for unit 0x%x (max: 125MHz)",
+		    unit);
+		return (0);
+	}
+	if (u > 0xfff) {
+		device_printf(sc->sc_dev,
+		    "Frequency too low for unit 0x%x (min: 123Hz)",
+		    unit);
+		return (0);
+	}
+	hz = 500000000/u;
+	W_CMDIV(sc, unit, u << 12);
+
+	W_CMCLK(sc, unit, 0x16);
+	for (i = 0; i < 10; i++) {
+		u = R_CMCLK(sc, unit);
+		if ((u&0x80))
+			break;
+		DELAY(1000);
+	}
+	if (!(u & 0x80)) {
+		device_printf(sc->sc_dev,
+		    "Failed to start clock for unit 0x%x", unit);
+		return (0);
+	}
+	return (hz);
+}
+
+static int
+bcm2835_clkman_detach(device_t dev)
+{
+	struct bcm2835_clkman_softc *sc;
+
+	bus_generic_detach(dev);
+
+	sc = device_get_softc(dev);
+	if (sc->sc_m_res)
+		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_m_res);
+
+	return (0);
+}
+
+static device_method_t bcm2835_clkman_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		bcm2835_clkman_probe),
+	DEVMETHOD(device_attach,	bcm2835_clkman_attach),
+	DEVMETHOD(device_detach,	bcm2835_clkman_detach),
+
+	DEVMETHOD_END
+};
+
+static devclass_t bcm2835_clkman_devclass;
+static driver_t bcm2835_clkman_driver = {
+	"bcm2835_clkman",
+	bcm2835_clkman_methods,
+	sizeof(struct bcm2835_clkman_softc),
+};
+
+DRIVER_MODULE(bcm2835_clkman, simplebus, bcm2835_clkman_driver,
+    bcm2835_clkman_devclass, 0, 0);
+MODULE_VERSION(bcm2835_clkman, 1);

Added: head/sys/arm/broadcom/bcm2835/bcm2835_clkman.h
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/arm/broadcom/bcm2835/bcm2835_clkman.h	Mon Jan 22 07:10:30 2018	(r328257)
@@ -0,0 +1,43 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2017 Poul-Henning Kamp <phk at FreeBSD.org>
+ *
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef	_BCM2835_CLKMAN_H_
+#define	_BCM2835_CLKMAN_H_
+
+// Offset into BAR0 for unit
+enum bcm2835_clksrc {
+	BCM_GPIO0_CLKSRC =	0x70,
+	BCM_GPIO1_CLKSRC =	0x78,
+	BCM_GPIO2_CLKSRC =	0x80,
+	BCM_PWM_CLKSRC =	0xa0,
+};
+
+uint32_t bcm2835_clkman_set_frequency(device_t, uint32_t, uint32_t);
+
+#endif	/* _BCM2835_CLKMAN_H_ */

Modified: head/sys/arm/broadcom/bcm2835/bcm2835_pwm.c
==============================================================================
--- head/sys/arm/broadcom/bcm2835/bcm2835_pwm.c	Mon Jan 22 06:00:45 2018	(r328256)
+++ head/sys/arm/broadcom/bcm2835/bcm2835_pwm.c	Mon Jan 22 07:10:30 2018	(r328257)
@@ -42,12 +42,12 @@ __FBSDID("$FreeBSD$");
 
 #include <machine/bus.h>
 #include <machine/resource.h>
-#include <machine/intr.h>
 
 #include <dev/ofw/ofw_bus.h>
 #include <dev/ofw/ofw_bus_subr.h>
 
 #include <arm/broadcom/bcm2835/bcm2835_gpio.h>
+#include <arm/broadcom/bcm2835/bcm2835_clkman.h>
 
 static struct ofw_compat_data compat_data[] = {
 	{"broadcom,bcm2835-pwm",	1},
@@ -62,9 +62,7 @@ struct bcm_pwm_softc {
 	bus_space_tag_t		sc_m_bst;
 	bus_space_handle_t	sc_m_bsh;
 
-	struct resource *	sc_clk_res;
-	bus_space_tag_t		sc_c_bst;
-	bus_space_handle_t	sc_c_bsh;
+	device_t		clkman;
 
 	uint32_t		freq;
 	uint32_t		period;
@@ -91,15 +89,9 @@ struct bcm_pwm_softc {
 #define W_DAT(_sc, _val) BCM_PWM_MEM_WRITE(_sc, 0x14, _val)
 #define R_DAT(_sc) BCM_PWM_MEM_READ(_sc, 0x14)
 
-#define W_CMCLK(_sc, _val) BCM_PWM_CLK_WRITE(_sc, 0x00, 0x5a000000 | (_val))
-#define R_CMCLK(_sc) BCM_PWM_CLK_READ(_sc, 0x00)
-#define W_CMDIV(_sc, _val) BCM_PWM_CLK_WRITE(_sc, 0x04, 0x5a000000 | (_val))
-#define R_CMDIV(_s) BCM_PWM_CLK_READ(_sc, 0x04)
-
 static int
 bcm_pwm_reconf(struct bcm_pwm_softc *sc)
 {
-	int i;
 	uint32_t u;
 	device_t gpio;
 
@@ -107,22 +99,10 @@ bcm_pwm_reconf(struct bcm_pwm_softc *sc)
 	W_CTL(sc, 0);
 
 	/* Stop PWM clock */
-	W_CMCLK(sc, 6);
-	for (i = 0; i < 10; i++) {
-		u = R_CMCLK(sc);
-		if (!(u&0x80))
-			break;
-		DELAY(1000);
-	}
-	if (u&0x80) {
-		device_printf(sc->sc_dev, "Failed to stop clock\n");
-		return(EIO);
-	}
+	(void)bcm2835_clkman_set_frequency(sc->clkman, BCM_PWM_CLKSRC, 0);
 
-	if (sc->mode == 0) {
-		// XXX: GPIO cfg ?
+	if (sc->mode == 0)
 		return (0);
-	}
 
 	/* Ask GPIO0 to set ALT0 for pin 12 */
 	gpio = devclass_get_device(devclass_find("gpio"), 0);
@@ -132,32 +112,11 @@ bcm_pwm_reconf(struct bcm_pwm_softc *sc)
 	}
 	bcm_gpio_set_alternate(gpio, 12, BCM_GPIO_ALT0);
 
-	/* Configure divider */
-	u = 500000000/sc->freq;
-	if (u < 4) {
-		device_printf(sc->sc_dev, "Freq too high (max 125MHz)\n");
-		return(EINVAL);
-	}
-	if (u > 0xfff) {
-		device_printf(sc->sc_dev, "Freq too low (min 123Hz)\n");
-		return(EINVAL);
-	}
-	sc->freq = 500000000/u;
-	W_CMDIV(sc, u << 12);
+	u = bcm2835_clkman_set_frequency(sc->clkman, BCM_PWM_CLKSRC, sc->freq);
+	if (u == 0)
+		return (EINVAL);
+	sc->freq = u;
 
-	/* Start PWM clock */
-	W_CMCLK(sc, 0x16);
-	for (i = 0; i < 10; i++) {
-		u = R_CMCLK(sc);
-		if ((u&0x80))
-			break;
-		DELAY(1000);
-	}
-	if (!(u&0x80)) {
-		device_printf(sc->sc_dev, "Failed to start clock\n");
-		return(EIO);
-	}
-
 	/* Config PWM */
 	W_RNG(sc, sc->period);
 	if (sc->ratio > sc->period)
@@ -266,19 +225,13 @@ bcm_pwm_reg_proc(SYSCTL_HANDLER_ARGS)
 	int error;
 
 	sc = (struct bcm_pwm_softc *)arg1;
-	if (arg2 & 0x100)
-		reg = BCM_PWM_CLK_READ(sc, arg2 & 0xff);
-	else
-		reg = BCM_PWM_MEM_READ(sc, arg2 & 0xff);
+	reg = BCM_PWM_MEM_READ(sc, arg2 & 0xff);
 
 	error = sysctl_handle_int(oidp, &reg, sizeof(reg), req);
 	if (error != 0 || req->newptr == NULL)
 		return (error);
 
-	if (arg2 & 0x100)
-		BCM_PWM_CLK_WRITE(sc, arg2 & 0xff, reg);
-	else
-		BCM_PWM_MEM_WRITE(sc, arg2, reg);
+	BCM_PWM_MEM_WRITE(sc, arg2, reg);
 	return (0);
 }
 
@@ -301,8 +254,6 @@ bcm_pwm_sysctl_init(struct bcm_pwm_softc *sc)
 	    CTLFLAG_RW | CTLTYPE_UINT, sc, 0x##x,		\
 	    bcm_pwm_reg_proc, "IU", "Register 0x" #x " " y);
 
-		RR(100, "PWMCTL")
-		RR(104, "PWMDIV")
 		RR(24, "DAT2")
 		RR(20, "RNG2")
 		RR(18, "FIF1")
@@ -335,8 +286,12 @@ static int
 bcm_pwm_probe(device_t dev)
 {
 
+#if 0
+	// XXX: default state is disabled in RPI3 DTB, assume for now
+	// XXX: that people want the PWM to work if the KLD this module.
 	if (!ofw_bus_status_okay(dev))
 		return (ENXIO);
+#endif
 
 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
 		return (ENXIO);
@@ -360,6 +315,12 @@ bcm_pwm_attach(device_t dev)
 	sc = device_get_softc(dev);
 	sc->sc_dev = dev;
 
+	sc->clkman = devclass_get_device(devclass_find("bcm2835_clkman"), 0);
+	if (sc->clkman == NULL) {
+		device_printf(dev, "cannot find Clock Manager\n");
+		return (ENXIO);
+	}
+
 	rid = 0;
 	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
 	    RF_ACTIVE);
@@ -371,16 +332,6 @@ bcm_pwm_attach(device_t dev)
 	sc->sc_m_bst = rman_get_bustag(sc->sc_mem_res);
 	sc->sc_m_bsh = rman_get_bushandle(sc->sc_mem_res);
 
-	rid = 1;
-	sc->sc_clk_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
-	    RF_ACTIVE);
-	if (!sc->sc_clk_res) {
-		device_printf(dev, "cannot allocate clock window\n");
-		return (ENXIO);
-	}
-	sc->sc_c_bst = rman_get_bustag(sc->sc_clk_res);
-	sc->sc_c_bsh = rman_get_bushandle(sc->sc_clk_res);
-
 	/* Add sysctl nodes. */
 	bcm_pwm_sysctl_init(sc);
 
@@ -400,12 +351,10 @@ bcm_pwm_detach(device_t dev)
 	bus_generic_detach(dev);
 
 	sc = device_get_softc(dev);
-	sc->mode = 0;	
+	sc->mode = 0;
 	(void)bcm_pwm_reconf(sc);
 	if (sc->sc_mem_res)
 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
-	if (sc->sc_clk_res)
-		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_clk_res);
 
 	return (0);
 }
@@ -414,17 +363,15 @@ static phandle_t
 bcm_pwm_get_node(device_t bus, device_t dev)
 {
 
-	/* We only have one child, the SPI bus, which needs our own node. */
 	return (ofw_bus_get_node(bus));
 }
 
+
 static device_method_t bcm_pwm_methods[] = {
 	/* Device interface */
 	DEVMETHOD(device_probe,		bcm_pwm_probe),
 	DEVMETHOD(device_attach,	bcm_pwm_attach),
 	DEVMETHOD(device_detach,	bcm_pwm_detach),
-
-	/* ofw_bus interface */
 	DEVMETHOD(ofw_bus_get_node,	bcm_pwm_get_node),
 
 	DEVMETHOD_END
@@ -439,3 +386,4 @@ static driver_t bcm_pwm_driver = {
 };
 
 DRIVER_MODULE(bcm2835_pwm, simplebus, bcm_pwm_driver, bcm_pwm_devclass, 0, 0);
+MODULE_DEPEND(bcm2835_pwm, bcm2835_clkman, 1, 1, 1);

Modified: head/sys/dts/arm/bcm2836.dtsi
==============================================================================
--- head/sys/dts/arm/bcm2836.dtsi	Mon Jan 22 06:00:45 2018	(r328256)
+++ head/sys/dts/arm/bcm2836.dtsi	Mon Jan 22 07:10:30 2018	(r328257)
@@ -389,6 +389,11 @@
 			};
 		};
 
+		cprman {
+			compatible = "broadcom,bcm2835-cprman";
+			reg = <0x101000 0x2000>;
+		};
+
 		rng {
 			compatible = "broadcom,bcm2835-rng",
 				     "broadcom,bcm2708-rng";
@@ -427,7 +432,7 @@
 
 		pwm0 {
 			compatible = "broadcom,bcm2835-pwm";
-			reg = <0x20c000 0x28>,<0x1010a0 8>;
+			reg = <0x20c000 0x28>;
 		};
 
 		dma: dma {

Modified: head/sys/modules/Makefile
==============================================================================
--- head/sys/modules/Makefile	Mon Jan 22 06:00:45 2018	(r328256)
+++ head/sys/modules/Makefile	Mon Jan 22 07:10:30 2018	(r328257)
@@ -60,6 +60,7 @@ SUBDIR=	\
 	${_autofs} \
 	${_auxio} \
 	${_bce} \
+	${_bcm283x_clkman} \
 	${_bcm283x_pwm} \
 	bfe \
 	bge \
@@ -808,6 +809,7 @@ _cloudabi64=	cloudabi64
 .endif
 
 .if ${MACHINE_ARCH:Marmv[67]*} != "" || ${MACHINE_CPUARCH} == "aarch64"
+_bcm283x_clkman=  bcm283x_clkman
 _bcm283x_pwm=  bcm283x_pwm
 .endif
 


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