]> git.ipfire.org Git - thirdparty/u-boot.git/commitdiff
dm: Add support for simple-pm-bus
authorSean Anderson <seanga2@gmail.com>
Wed, 24 Jun 2020 10:41:12 +0000 (06:41 -0400)
committerAndes <uboot@andestech.com>
Wed, 1 Jul 2020 07:01:21 +0000 (15:01 +0800)
This type of bus is used in Linux to designate buses which have power
domains and/or clocks which need to be enabled before their child devices
can be used. Because power domains are automatically enabled before probing
in U-Boot, we just need to enable any clocks present.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
arch/sandbox/dts/test.dts
arch/sandbox/include/asm/clk.h
configs/sandbox_defconfig
doc/device-tree-bindings/bus/simple-pm-bus.txt [new file with mode: 0644]
drivers/core/Kconfig
drivers/core/Makefile
drivers/core/simple-pm-bus.c [new file with mode: 0644]
test/dm/Makefile
test/dm/simple-pm-bus.c [new file with mode: 0644]

index a6e2bfd082f63211801dff6baa3685f404610216..b59bf157a9144c28d20ce5f93c8d8ef6eef7f505 100644 (file)
        mdio: mdio-test {
                compatible = "sandbox,mdio";
        };
+
+       pm-bus-test {
+               compatible = "simple-pm-bus";
+               clocks = <&clk_sandbox 4>;
+               power-domains = <&pwrdom 1>;
+       };
 };
 
 #include "sandbox_pmic.dtsi"
index 1573e4a13474edd025d54fc1bb154aa8a2499db2..c184c4bffcf7b7ade69cc400bfa38119197994fc 100644 (file)
@@ -21,6 +21,7 @@ enum sandbox_clk_id {
        SANDBOX_CLK_ID_I2C,
        SANDBOX_CLK_ID_UART1,
        SANDBOX_CLK_ID_UART2,
+       SANDBOX_CLK_ID_BUS,
 
        SANDBOX_CLK_ID_COUNT,
 };
index 20a81a0350d2ddf1e444b18e34bd680f015bbdb8..692432c7d69a98005068b931df43d4c9525337be 100644 (file)
@@ -96,6 +96,7 @@ CONFIG_REGMAP=y
 CONFIG_SYSCON=y
 CONFIG_DEVRES=y
 CONFIG_DEBUG_DEVRES=y
+CONFIG_SIMPLE_PM_BUS=y
 CONFIG_ADC=y
 CONFIG_ADC_SANDBOX=y
 CONFIG_AXI=y
diff --git a/doc/device-tree-bindings/bus/simple-pm-bus.txt b/doc/device-tree-bindings/bus/simple-pm-bus.txt
new file mode 100644 (file)
index 0000000..6f15037
--- /dev/null
@@ -0,0 +1,44 @@
+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 the Devicetree Specification, 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>;
+       };
index a3b0399342366a40b562e360b8c12847feb258d3..a594899f371ebe3a874d4104137783c02b4eaf92 100644 (file)
@@ -195,6 +195,13 @@ config SPL_SIMPLE_BUS
          Supports the 'simple-bus' driver, which is used on some systems
          in SPL.
 
+config SIMPLE_PM_BUS
+       bool "Support simple-pm-bus driver"
+       depends on DM && OF_CONTROL && CLK && POWER_DOMAIN
+       help
+         Supports the 'simple-pm-bus' driver, which is used for busses that
+         have power domains and/or clocks which need to be enabled before use.
+
 config OF_TRANSLATE
        bool "Translate addresses using fdt_translate_address"
        depends on DM && OF_CONTROL
index c707026a3a029f4c375594e99497205cf85b78fe..10f4bece3353c677524fbbf040462fc08e0e55a5 100644 (file)
@@ -7,6 +7,7 @@ obj-$(CONFIG_$(SPL_TPL_)ACPIGEN) += acpi.o
 obj-$(CONFIG_DEVRES) += devres.o
 obj-$(CONFIG_$(SPL_)DM_DEVICE_REMOVE)  += device-remove.o
 obj-$(CONFIG_$(SPL_)SIMPLE_BUS)        += simple-bus.o
+obj-$(CONFIG_SIMPLE_PM_BUS)    += simple-pm-bus.o
 obj-$(CONFIG_DM)       += dump.o
 obj-$(CONFIG_$(SPL_TPL_)REGMAP)        += regmap.o
 obj-$(CONFIG_$(SPL_TPL_)SYSCON)        += syscon-uclass.o
diff --git a/drivers/core/simple-pm-bus.c b/drivers/core/simple-pm-bus.c
new file mode 100644 (file)
index 0000000..51dc9b2
--- /dev/null
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 Sean Anderson <seanga2@gmail.com>
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+
+/*
+ * Power domains are taken care of by driver_probe, so we just have to enable
+ * clocks
+ */
+static int simple_pm_bus_probe(struct udevice *dev)
+{
+       int ret;
+       struct clk_bulk *bulk = dev_get_priv(dev);
+
+       ret = clk_get_bulk(dev, bulk);
+       if (ret)
+               return ret;
+
+       ret = clk_enable_bulk(bulk);
+       if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
+               clk_release_bulk(bulk);
+               return ret;
+       }
+       return 0;
+}
+
+static int simple_pm_bus_remove(struct udevice *dev)
+{
+       int ret;
+       struct clk_bulk *bulk = dev_get_priv(dev);
+
+       ret = clk_release_bulk(bulk);
+       if (ret && ret != -ENOSYS && ret != -ENOTSUPP)
+               return ret;
+       else
+               return 0;
+}
+
+static const struct udevice_id simple_pm_bus_ids[] = {
+       { .compatible = "simple-pm-bus" },
+       { }
+};
+
+U_BOOT_DRIVER(simple_pm_bus_drv) = {
+       .name   = "simple_pm_bus",
+       .id     = UCLASS_SIMPLE_BUS,
+       .of_match = simple_pm_bus_ids,
+       .probe = simple_pm_bus_probe,
+       .remove = simple_pm_bus_remove,
+       .priv_auto_alloc_size = sizeof(struct clk_bulk),
+       .flags  = DM_FLAG_PRE_RELOC,
+};
index 5094a7866af64523a3198107a3906c0f4e53ef29..518ee8e377315885de7d281d24a1dd0e1e4e273b 100644 (file)
@@ -74,4 +74,5 @@ obj-$(CONFIG_DM_MDIO) += mdio.o
 obj-$(CONFIG_DM_MDIO_MUX) += mdio_mux.o
 obj-$(CONFIG_DM_RNG) += rng.o
 obj-$(CONFIG_CLK_K210_SET_RATE) += k210_pll.o
+obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o
 endif
diff --git a/test/dm/simple-pm-bus.c b/test/dm/simple-pm-bus.c
new file mode 100644 (file)
index 0000000..978c7f1
--- /dev/null
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Sean Anderson <seanga2@gmail.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/test.h>
+#include <dm/device-internal.h>
+#include <test/ut.h>
+#include <asm/clk.h>
+#include <asm/power-domain.h>
+
+/* These must match the ids in the device tree */
+#define TEST_CLOCK_ID 4
+#define TEST_POWER_ID 1
+
+static int dm_test_simple_pm_bus(struct unit_test_state *uts)
+{
+       struct udevice *power;
+       struct udevice *clock;
+       struct udevice *bus;
+
+       ut_assertok(uclass_get_device_by_name(UCLASS_POWER_DOMAIN,
+                                             "power-domain", &power));
+       ut_assertok(uclass_get_device_by_name(UCLASS_CLK, "clk-sbox",
+                                             &clock));
+       ut_asserteq(0, sandbox_power_domain_query(power, TEST_POWER_ID));
+       ut_asserteq(0, sandbox_clk_query_enable(clock, TEST_CLOCK_ID));
+
+       ut_assertok(uclass_get_device_by_name(UCLASS_SIMPLE_BUS, "pm-bus-test",
+                                             &bus));
+       ut_asserteq(1, sandbox_power_domain_query(power, TEST_POWER_ID));
+       ut_asserteq(1, sandbox_clk_query_enable(clock, TEST_CLOCK_ID));
+
+       ut_assertok(device_remove(bus, DM_REMOVE_NORMAL));
+       /* must re-probe since device_remove also removes the power domain */
+       ut_assertok(uclass_get_device_by_name(UCLASS_POWER_DOMAIN,
+                                             "power-domain", &power));
+       ut_asserteq(0, sandbox_power_domain_query(power, TEST_POWER_ID));
+       ut_asserteq(0, sandbox_clk_query_enable(clock, TEST_CLOCK_ID));
+
+       return 0;
+}
+DM_TEST(dm_test_simple_pm_bus, DM_TESTF_SCAN_FDT);