--- /dev/null
+Renesas Bus State Controller (BSC)
+==================================
+
+The Renesas Bus State Controller (BSC, sometimes called "LBSC within Bus
+Bridge", or "External Bus Interface") can be found in several Renesas ARM SoCs.
+It provides an external bus for connecting multiple external devices to the
+SoC, driving several chip select lines, for e.g. NOR FLASH, Ethernet and USB.
+
+While the BSC is a fairly simple memory-mapped bus, it may be part of a PM
+domain, and may have a gateable functional clock.
+Before a device connected to the BSC can be accessed, the PM domain
+containing the BSC must be powered on, and the functional clock
+driving the BSC must be enabled.
+
+The bindings for the BSC extend the bindings for "simple-pm-bus".
+
+
+Required properties
+ - compatible: Must contain an SoC-specific value, and "renesas,bsc" and
+ "simple-pm-bus" as fallbacks.
+ SoC-specific values can be:
+ "renesas,bsc-r8a73a4" for R-Mobile APE6 (r8a73a4)
+ "renesas,bsc-sh73a0" for SH-Mobile AG5 (sh73a0)
+ - #address-cells, #size-cells, ranges: Must describe the mapping between
+ parent address and child address spaces.
+ - reg: Must contain the base address and length to access the bus controller.
+
+Optional properties:
+ - interrupts: Must contain a reference to the BSC interrupt, if available.
+ - clocks: Must contain a reference to the functional clock, if available.
+ - power-domains: Must contain a reference to the PM domain, if available.
+
+
+Example:
+
+ bsc: bus@fec10000 {
+ compatible = "renesas,bsc-sh73a0", "renesas,bsc",
+ "simple-pm-bus";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 0 0x20000000>;
+ reg = <0xfec10000 0x400>;
+ interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&zb_clk>;
+ power-domains = <&pd_a4s>;
+ };
--- /dev/null
+Simple Power-Managed Bus
+========================
+
+A Simple Power-Managed Bus is a transparent bus that doesn't need a real
+driver, as it's typically initialized by the boot loader.
+
+However, its bus controller is part of a PM domain, or under the control of a
+functional clock. Hence, the bus controller's PM domain and/or clock must be
+enabled for child devices connected to the bus (either on-SoC or externally)
+to function.
+
+While "simple-pm-bus" follows the "simple-bus" set of properties, as specified
+in ePAPR, it is not an extension of "simple-bus".
+
+
+Required properties:
+ - compatible: Must contain at least "simple-pm-bus".
+ Must not contain "simple-bus".
+ It's recommended to let this be preceded by one or more
+ vendor-specific compatible values.
+ - #address-cells, #size-cells, ranges: Must describe the mapping between
+ parent address and child address spaces.
+
+Optional platform-specific properties for clock or PM domain control (at least
+one of them is required):
+ - clocks: Must contain a reference to the functional clock(s),
+ - power-domains: Must contain a reference to the PM domain.
+Please refer to the binding documentation for the clock and/or PM domain
+providers for more details.
+
+
+Example:
+
+ bsc: bus@fec10000 {
+ compatible = "renesas,bsc-sh73a0", "renesas,bsc",
+ "simple-pm-bus";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 0 0x20000000>;
+ reg = <0xfec10000 0x400>;
+ interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&zb_clk>;
+ power-domains = <&pd_a4s>;
+ };
menu "Bus devices"
+config ARM_CCI
+ bool "ARM CCI driver support"
+ depends on ARM && OF && CPU_V7
+ help
+ Driver supporting the CCI cache coherent interconnect for ARM
+ platforms.
+
+config ARM_CCN
+ bool "ARM CCN driver support"
+ depends on ARM || ARM64
+ depends on PERF_EVENTS
+ help
+ PMU (perf) driver supporting the ARM CCN (Cache Coherent Network)
+ interconnect.
+
config BRCMSTB_GISB_ARB
bool "Broadcom STB GISB bus arbiter"
depends on ARM || MIPS
Driver needed for the MBus configuration on Marvell EBU SoCs
(Kirkwood, Dove, Orion5x, MV78XX0 and Armada 370/XP).
-config OMAP_OCP2SCP
- tristate "OMAP OCP2SCP DRIVER"
- depends on ARCH_OMAP2PLUS
- help
- Driver to enable ocp2scp module which transforms ocp interface
- protocol to scp protocol. In OMAP4, USB PHY is connected via
- OCP2SCP and in OMAP5, both USB PHY and SATA PHY is connected via
- OCP2SCP.
-
config OMAP_INTERCONNECT
tristate "OMAP INTERCONNECT DRIVER"
depends on ARCH_OMAP2PLUS
help
Driver to enable OMAP interconnect error handling driver.
-config ARM_CCI
- bool "ARM CCI driver support"
- depends on ARM && OF && CPU_V7
+config OMAP_OCP2SCP
+ tristate "OMAP OCP2SCP DRIVER"
+ depends on ARCH_OMAP2PLUS
help
- Driver supporting the CCI cache coherent interconnect for ARM
- platforms.
+ Driver to enable ocp2scp module which transforms ocp interface
+ protocol to scp protocol. In OMAP4, USB PHY is connected via
+ OCP2SCP and in OMAP5, both USB PHY and SATA PHY is connected via
+ OCP2SCP.
-config ARM_CCN
- bool "ARM CCN driver support"
- depends on ARM || ARM64
- depends on PERF_EVENTS
+config SIMPLE_PM_BUS
+ bool "Simple Power-Managed Bus Driver"
+ depends on OF && PM
+ depends on ARCH_SHMOBILE || COMPILE_TEST
help
- PMU (perf) driver supporting the ARM CCN (Cache Coherent Network)
- interconnect.
+ Driver for transparent busses that don't need a real driver, but
+ where the bus controller is part of a PM domain, or under the control
+ of a functional clock, and thus relies on runtime PM for managing
+ this PM domain and/or clock.
+ An example of such a bus controller is the Renesas Bus State
+ Controller (BSC, sometimes called "LBSC within Bus Bridge", or
+ "External Bus Interface") as found on several Renesas ARM SoCs.
config VEXPRESS_CONFIG
bool "Versatile Express configuration bus"
# Makefile for the bus drivers.
#
+# Interconnect bus drivers for ARM platforms
+obj-$(CONFIG_ARM_CCI) += arm-cci.o
+obj-$(CONFIG_ARM_CCN) += arm-ccn.o
+
obj-$(CONFIG_BRCMSTB_GISB_ARB) += brcmstb_gisb.o
-obj-$(CONFIG_IMX_WEIM) += imx-weim.o
-obj-$(CONFIG_MVEBU_MBUS) += mvebu-mbus.o
-obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o
+obj-$(CONFIG_IMX_WEIM) += imx-weim.o
+obj-$(CONFIG_MVEBU_MBUS) += mvebu-mbus.o
# Interconnect bus driver for OMAP SoCs.
obj-$(CONFIG_OMAP_INTERCONNECT) += omap_l3_smx.o omap_l3_noc.o
-# Interconnect bus drivers for ARM platforms
-obj-$(CONFIG_ARM_CCI) += arm-cci.o
-obj-$(CONFIG_ARM_CCN) += arm-ccn.o
-
+obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o
+obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o
obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o
--- /dev/null
+/*
+ * Simple Power-Managed Bus Driver
+ *
+ * Copyright (C) 2014-2015 Glider bvba
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+
+static int simple_pm_bus_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+
+ pm_runtime_enable(&pdev->dev);
+
+ if (np)
+ of_platform_populate(np, NULL, NULL, &pdev->dev);
+
+ return 0;
+}
+
+static int simple_pm_bus_remove(struct platform_device *pdev)
+{
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+
+ pm_runtime_disable(&pdev->dev);
+ return 0;
+}
+
+static const struct of_device_id simple_pm_bus_of_match[] = {
+ { .compatible = "simple-pm-bus", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, simple_pm_bus_of_match);
+
+static struct platform_driver simple_pm_bus_driver = {
+ .probe = simple_pm_bus_probe,
+ .remove = simple_pm_bus_remove,
+ .driver = {
+ .name = "simple-pm-bus",
+ .of_match_table = simple_pm_bus_of_match,
+ },
+};
+
+module_platform_driver(simple_pm_bus_driver);
+
+MODULE_DESCRIPTION("Simple Power-Managed Bus Driver");
+MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
+MODULE_LICENSE("GPL v2");
projects / linux-2.6-block.git / commitdiff