[PATCH 0/5] Add support of STM32 hwspinlock

[PATCH 0/5] Add support of STM32 hwspinlock

[Benjamin Gaignard]

This serie adds the support of the hardware semaphore block for stm32mp1 SoC.
The last patch isn't related to the hardware itself but propose a way to test
hwspinlocks.

Benjamin Gaignard (5):
  dt-bindings: hwlock: Document STM32 hwspinlock bindings
  hwspinlock: add STM32 hwspinlock device
  ARM: dts: stm32: Add hwspinlock node for stm32mp157 SoC
  ARM: dts: stm32: enable hwspinlock on stm32mp157c-ed1
  hwspinlock: Add test module

 .../bindings/hwlock/st,stm32-hwspinlock.txt        |  23 ++++
 arch/arm/boot/dts/stm32mp157c-ed1.dts              |   4 +
 arch/arm/boot/dts/stm32mp157c.dtsi                 |   9 ++
 drivers/hwspinlock/Kconfig                         |  18 +++
 drivers/hwspinlock/Makefile                        |   2 +
 drivers/hwspinlock/hwspinlock_test.c               | 132 ++++++++++++++++++
 drivers/hwspinlock/stm32_hwspinlock.c              | 147 +++++++++++++++++++++
 7 files changed, 335 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
 create mode 100644 drivers/hwspinlock/hwspinlock_test.c
 create mode 100644 drivers/hwspinlock/stm32_hwspinlock.c

-- 
2.15.0

[PATCH 0/5] Add support of STM32 hwspinlock

[Benjamin Gaignard]

This serie adds the support of the hardware semaphore block for stm32mp1 SoC.
The last patch isn't related to the hardware itself but propose a way to test
hwspinlocks.

Benjamin Gaignard (5):
  dt-bindings: hwlock: Document STM32 hwspinlock bindings
  hwspinlock: add STM32 hwspinlock device
  ARM: dts: stm32: Add hwspinlock node for stm32mp157 SoC
  ARM: dts: stm32: enable hwspinlock on stm32mp157c-ed1
  hwspinlock: Add test module

 .../bindings/hwlock/st,stm32-hwspinlock.txt        |  23 ++++
 arch/arm/boot/dts/stm32mp157c-ed1.dts              |   4 +
 arch/arm/boot/dts/stm32mp157c.dtsi                 |   9 ++
 drivers/hwspinlock/Kconfig                         |  18 +++
 drivers/hwspinlock/Makefile                        |   2 +
 drivers/hwspinlock/hwspinlock_test.c               | 132 ++++++++++++++++++
 drivers/hwspinlock/stm32_hwspinlock.c              | 147 +++++++++++++++++++++
 7 files changed, 335 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
 create mode 100644 drivers/hwspinlock/hwspinlock_test.c
 create mode 100644 drivers/hwspinlock/stm32_hwspinlock.c

-- 
2.15.0

[PATCH 1/5] dt-bindings: hwlock: Document STM32 hwspinlock bindings

[Benjamin Gaignard]

Add bindings for STM32 hardware spinlock device

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 .../bindings/hwlock/st,stm32-hwspinlock.txt        | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt

diff --git a/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
new file mode 100644
index 000000000000..7a999479d802
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
@@ -0,0 +1,23 @@
+STM32 Hardware Spinlock Device Binding
+-------------------------------------
+
+Required properties :
+- compatible : should be "st,stm32-hwspinlock".
+- reg : the register address of hwspinlock.
+- #hwlock-cells : hwlock users only use the hwlock id to represent a specific
+	hwlock, so the number of cells should be <1> here.
+- clock-names : Must contain "hwspinlock".
+- clocks : Must contain a phandle entry for the clock in clock-names, see the
+	common clock bindings.
+
+Please look at the generic hwlock binding for usage information for consumers,
+"Documentation/devicetree/bindings/hwlock/hwlock.txt"
+
+Example of hwlock provider:
+	hwspinlock@4c000000 {
+		compatible = "st,stm32-hwspinlock";
+		#hwlock-cells = <1>;
+		reg = <0x4c000000 0x400>;
+		clocks = <&rcc HSEM>;
+		clock-names = "hwspinlock";
+	};
-- 
2.15.0

[PATCH 1/5] dt-bindings: hwlock: Document STM32 hwspinlock bindings

[Benjamin Gaignard]

Add bindings for STM32 hardware spinlock device

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 .../bindings/hwlock/st,stm32-hwspinlock.txt        | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt

diff --git a/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
new file mode 100644
index 000000000000..7a999479d802
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
@@ -0,0 +1,23 @@
+STM32 Hardware Spinlock Device Binding
+-------------------------------------
+
+Required properties :
+- compatible : should be "st,stm32-hwspinlock".
+- reg : the register address of hwspinlock.
+- #hwlock-cells : hwlock users only use the hwlock id to represent a specific
+	hwlock, so the number of cells should be <1> here.
+- clock-names : Must contain "hwspinlock".
+- clocks : Must contain a phandle entry for the clock in clock-names, see the
+	common clock bindings.
+
+Please look at the generic hwlock binding for usage information for consumers,
+"Documentation/devicetree/bindings/hwlock/hwlock.txt"
+
+Example of hwlock provider:
+	hwspinlock at 4c000000 {
+		compatible = "st,stm32-hwspinlock";
+		#hwlock-cells = <1>;
+		reg = <0x4c000000 0x400>;
+		clocks = <&rcc HSEM>;
+		clock-names = "hwspinlock";
+	};
-- 
2.15.0

[PATCH 2/5] hwspinlock: add STM32 hwspinlock device

[Benjamin Gaignard]

This patch adds support of hardware semaphores for stm32mp1 SoC.
The hardware block provides 32 semaphores.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 drivers/hwspinlock/Kconfig            |   9 +++
 drivers/hwspinlock/Makefile           |   1 +
 drivers/hwspinlock/stm32_hwspinlock.c | 147 ++++++++++++++++++++++++++++++++++
 3 files changed, 157 insertions(+)
 create mode 100644 drivers/hwspinlock/stm32_hwspinlock.c

diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index e895d29500ee..e1a20b460590 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -59,3 +59,12 @@ config HSEM_U8500
 	  SoC.
 
 	  If unsure, say N.
+
+config HWSPINLOCK_STM32
+	tristate "STM32 Hardware Spinlock device"
+	depends on MACH_STM32MP157
+	depends on HWSPINLOCK
+	help
+	  Say y here to support the STM32 Hardware Spinlock device.
+
+	  If unsure, say N.
diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index b87c01a506a4..c0a9505b4dcf 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_HWSPINLOCK_QCOM)		+= qcom_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
 obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
+obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o
diff --git a/drivers/hwspinlock/stm32_hwspinlock.c b/drivers/hwspinlock/stm32_hwspinlock.c
new file mode 100644
index 000000000000..6a0fafac7389
--- /dev/null
+++ b/drivers/hwspinlock/stm32_hwspinlock.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2018
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/hwspinlock.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "hwspinlock_internal.h"
+
+#define STM32_MUTEX_COREID	BIT(8)
+#define STM32_MUTEX_LOCK_BIT	BIT(31)
+#define STM32_MUTEX_NUM_LOCKS	32
+
+struct stm32_hwspinlock {
+	struct clk *clk;
+	struct hwspinlock_device bank;
+};
+
+static int stm32_hwspinlock_trylock(struct hwspinlock *lock)
+{
+	void __iomem *lock_addr = lock->priv;
+	u32 status;
+
+	writel(STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID, lock_addr);
+	status = readl(lock_addr);
+
+	return status == (STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID);
+}
+
+static void stm32_hwspinlock_unlock(struct hwspinlock *lock)
+{
+	void __iomem *lock_addr = lock->priv;
+
+	writel(STM32_MUTEX_COREID, lock_addr);
+}
+
+static const struct hwspinlock_ops stm32_hwspinlock_ops = {
+	.trylock	= stm32_hwspinlock_trylock,
+	.unlock		= stm32_hwspinlock_unlock,
+};
+
+static int stm32_hwspinlock_probe(struct platform_device *pdev)
+{
+	struct stm32_hwspinlock *hw;
+	void __iomem *io_base;
+	struct resource *res;
+	size_t array_size;
+	int i, ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	io_base = devm_ioremap_resource(&pdev->dev, res);
+	if (!io_base)
+		return -ENOMEM;
+
+	array_size = STM32_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock);
+	hw = devm_kzalloc(&pdev->dev, sizeof(*hw) + array_size, GFP_KERNEL);
+	if (!hw)
+		return -ENOMEM;
+
+	hw->clk = devm_clk_get(&pdev->dev, "hwspinlock");
+	if (IS_ERR(hw->clk))
+		return PTR_ERR(hw->clk);
+
+	for (i = 0; i < STM32_MUTEX_NUM_LOCKS; i++)
+		hw->bank.lock[i].priv = io_base + i * sizeof(u32);
+
+	platform_set_drvdata(pdev, hw);
+	pm_runtime_enable(&pdev->dev);
+
+	ret = hwspin_lock_register(&hw->bank, &pdev->dev, &stm32_hwspinlock_ops,
+				   0, STM32_MUTEX_NUM_LOCKS);
+
+	if (ret)
+		pm_runtime_disable(&pdev->dev);
+
+	return ret;
+}
+
+static int stm32_hwspinlock_remove(struct platform_device *pdev)
+{
+	struct stm32_hwspinlock *hw = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = hwspin_lock_unregister(&hw->bank);
+	if (ret) {
+		dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
+		return ret;
+	}
+
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_hwspinlock_runtime_suspend(struct device *dev)
+{
+	struct stm32_hwspinlock *hw = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(hw->clk);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_hwspinlock_runtime_resume(struct device *dev)
+{
+	struct stm32_hwspinlock *hw = dev_get_drvdata(dev);
+
+	clk_prepare_enable(hw->clk);
+
+	return 0;
+}
+
+static const struct dev_pm_ops stm32_hwspinlock_pm_ops = {
+	SET_RUNTIME_PM_OPS(stm32_hwspinlock_runtime_suspend,
+			   stm32_hwspinlock_runtime_resume,
+			   NULL)
+};
+
+static const struct of_device_id stm32_hwpinlock_ids[] = {
+	{ .compatible = "st,stm32-hwspinlock", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, stm32_hwpinlock_ids);
+
+static struct platform_driver stm32_hwspinlock_driver = {
+	.probe		= stm32_hwspinlock_probe,
+	.remove		= stm32_hwspinlock_remove,
+	.driver		= {
+		.name	= "stm32_hwspinlock",
+		.of_match_table = stm32_hwpinlock_ids,
+		.pm	= &stm32_hwspinlock_pm_ops,
+	},
+};
+module_platform_driver(stm32_hwspinlock_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Hardware spinlock driver for STM32 SoCs");
+MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
-- 
2.15.0

[PATCH 2/5] hwspinlock: add STM32 hwspinlock device

[Benjamin Gaignard]

This patch adds support of hardware semaphores for stm32mp1 SoC.
The hardware block provides 32 semaphores.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 drivers/hwspinlock/Kconfig            |   9 +++
 drivers/hwspinlock/Makefile           |   1 +
 drivers/hwspinlock/stm32_hwspinlock.c | 147 ++++++++++++++++++++++++++++++++++
 3 files changed, 157 insertions(+)
 create mode 100644 drivers/hwspinlock/stm32_hwspinlock.c

diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index e895d29500ee..e1a20b460590 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -59,3 +59,12 @@ config HSEM_U8500
 	  SoC.
 
 	  If unsure, say N.
+
+config HWSPINLOCK_STM32
+	tristate "STM32 Hardware Spinlock device"
+	depends on MACH_STM32MP157
+	depends on HWSPINLOCK
+	help
+	  Say y here to support the STM32 Hardware Spinlock device.
+
+	  If unsure, say N.
diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index b87c01a506a4..c0a9505b4dcf 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_HWSPINLOCK_QCOM)		+= qcom_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
 obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
+obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o
diff --git a/drivers/hwspinlock/stm32_hwspinlock.c b/drivers/hwspinlock/stm32_hwspinlock.c
new file mode 100644
index 000000000000..6a0fafac7389
--- /dev/null
+++ b/drivers/hwspinlock/stm32_hwspinlock.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2018
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/hwspinlock.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "hwspinlock_internal.h"
+
+#define STM32_MUTEX_COREID	BIT(8)
+#define STM32_MUTEX_LOCK_BIT	BIT(31)
+#define STM32_MUTEX_NUM_LOCKS	32
+
+struct stm32_hwspinlock {
+	struct clk *clk;
+	struct hwspinlock_device bank;
+};
+
+static int stm32_hwspinlock_trylock(struct hwspinlock *lock)
+{
+	void __iomem *lock_addr = lock->priv;
+	u32 status;
+
+	writel(STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID, lock_addr);
+	status = readl(lock_addr);
+
+	return status == (STM32_MUTEX_LOCK_BIT | STM32_MUTEX_COREID);
+}
+
+static void stm32_hwspinlock_unlock(struct hwspinlock *lock)
+{
+	void __iomem *lock_addr = lock->priv;
+
+	writel(STM32_MUTEX_COREID, lock_addr);
+}
+
+static const struct hwspinlock_ops stm32_hwspinlock_ops = {
+	.trylock	= stm32_hwspinlock_trylock,
+	.unlock		= stm32_hwspinlock_unlock,
+};
+
+static int stm32_hwspinlock_probe(struct platform_device *pdev)
+{
+	struct stm32_hwspinlock *hw;
+	void __iomem *io_base;
+	struct resource *res;
+	size_t array_size;
+	int i, ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	io_base = devm_ioremap_resource(&pdev->dev, res);
+	if (!io_base)
+		return -ENOMEM;
+
+	array_size = STM32_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock);
+	hw = devm_kzalloc(&pdev->dev, sizeof(*hw) + array_size, GFP_KERNEL);
+	if (!hw)
+		return -ENOMEM;
+
+	hw->clk = devm_clk_get(&pdev->dev, "hwspinlock");
+	if (IS_ERR(hw->clk))
+		return PTR_ERR(hw->clk);
+
+	for (i = 0; i < STM32_MUTEX_NUM_LOCKS; i++)
+		hw->bank.lock[i].priv = io_base + i * sizeof(u32);
+
+	platform_set_drvdata(pdev, hw);
+	pm_runtime_enable(&pdev->dev);
+
+	ret = hwspin_lock_register(&hw->bank, &pdev->dev, &stm32_hwspinlock_ops,
+				   0, STM32_MUTEX_NUM_LOCKS);
+
+	if (ret)
+		pm_runtime_disable(&pdev->dev);
+
+	return ret;
+}
+
+static int stm32_hwspinlock_remove(struct platform_device *pdev)
+{
+	struct stm32_hwspinlock *hw = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = hwspin_lock_unregister(&hw->bank);
+	if (ret) {
+		dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
+		return ret;
+	}
+
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_hwspinlock_runtime_suspend(struct device *dev)
+{
+	struct stm32_hwspinlock *hw = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(hw->clk);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_hwspinlock_runtime_resume(struct device *dev)
+{
+	struct stm32_hwspinlock *hw = dev_get_drvdata(dev);
+
+	clk_prepare_enable(hw->clk);
+
+	return 0;
+}
+
+static const struct dev_pm_ops stm32_hwspinlock_pm_ops = {
+	SET_RUNTIME_PM_OPS(stm32_hwspinlock_runtime_suspend,
+			   stm32_hwspinlock_runtime_resume,
+			   NULL)
+};
+
+static const struct of_device_id stm32_hwpinlock_ids[] = {
+	{ .compatible = "st,stm32-hwspinlock", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, stm32_hwpinlock_ids);
+
+static struct platform_driver stm32_hwspinlock_driver = {
+	.probe		= stm32_hwspinlock_probe,
+	.remove		= stm32_hwspinlock_remove,
+	.driver		= {
+		.name	= "stm32_hwspinlock",
+		.of_match_table = stm32_hwpinlock_ids,
+		.pm	= &stm32_hwspinlock_pm_ops,
+	},
+};
+module_platform_driver(stm32_hwspinlock_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Hardware spinlock driver for STM32 SoCs");
+MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
-- 
2.15.0

[PATCH 3/5] ARM: dts: stm32: Add hwspinlock node for stm32mp157 SoC

[Benjamin Gaignard]

Declare hwspinlock device for stm32mp157 SoC

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 arch/arm/boot/dts/stm32mp157c.dtsi | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm/boot/dts/stm32mp157c.dtsi b/arch/arm/boot/dts/stm32mp157c.dtsi
index 185541a5b69f..9b16c28f8ac3 100644
--- a/arch/arm/boot/dts/stm32mp157c.dtsi
+++ b/arch/arm/boot/dts/stm32mp157c.dtsi
@@ -803,6 +803,15 @@
 			status = "disabled";
 		};
 
+		hsem: hwspinlock@4c000000 {
+			compatible = "st,stm32-hwspinlock";
+			#hwlock-cells = <1>;
+			reg = <0x4c000000 0x400>;
+			clocks = <&rcc HSEM>;
+			clock-names = "hwspinlock";
+			status = "disabled";
+		};
+
 		rcc: rcc@50000000 {
 			compatible = "st,stm32mp1-rcc", "syscon";
 			reg = <0x50000000 0x1000>;
-- 
2.15.0

[PATCH 3/5] ARM: dts: stm32: Add hwspinlock node for stm32mp157 SoC

[Benjamin Gaignard]

Declare hwspinlock device for stm32mp157 SoC

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 arch/arm/boot/dts/stm32mp157c.dtsi | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm/boot/dts/stm32mp157c.dtsi b/arch/arm/boot/dts/stm32mp157c.dtsi
index 185541a5b69f..9b16c28f8ac3 100644
--- a/arch/arm/boot/dts/stm32mp157c.dtsi
+++ b/arch/arm/boot/dts/stm32mp157c.dtsi
@@ -803,6 +803,15 @@
 			status = "disabled";
 		};
 
+		hsem: hwspinlock at 4c000000 {
+			compatible = "st,stm32-hwspinlock";
+			#hwlock-cells = <1>;
+			reg = <0x4c000000 0x400>;
+			clocks = <&rcc HSEM>;
+			clock-names = "hwspinlock";
+			status = "disabled";
+		};
+
 		rcc: rcc at 50000000 {
 			compatible = "st,stm32mp1-rcc", "syscon";
 			reg = <0x50000000 0x1000>;
-- 
2.15.0

[PATCH 4/5] ARM: dts: stm32: enable hwspinlock on stm32mp157c-ed1

[Benjamin Gaignard]

Enable hwspinlock on stm32mp157c-ed1

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 arch/arm/boot/dts/stm32mp157c-ed1.dts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/boot/dts/stm32mp157c-ed1.dts b/arch/arm/boot/dts/stm32mp157c-ed1.dts
index f77bea49c079..158a337b3129 100644
--- a/arch/arm/boot/dts/stm32mp157c-ed1.dts
+++ b/arch/arm/boot/dts/stm32mp157c-ed1.dts
@@ -94,3 +94,7 @@
 	vdda1v1-supply = <&reg11>;
 	vdda1v8-supply = <&reg18>;
 };
+
+&hsem {
+	status = "okay";
+};
-- 
2.15.0

[PATCH 4/5] ARM: dts: stm32: enable hwspinlock on stm32mp157c-ed1

[Benjamin Gaignard]

Enable hwspinlock on stm32mp157c-ed1

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 arch/arm/boot/dts/stm32mp157c-ed1.dts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/boot/dts/stm32mp157c-ed1.dts b/arch/arm/boot/dts/stm32mp157c-ed1.dts
index f77bea49c079..158a337b3129 100644
--- a/arch/arm/boot/dts/stm32mp157c-ed1.dts
+++ b/arch/arm/boot/dts/stm32mp157c-ed1.dts
@@ -94,3 +94,7 @@
 	vdda1v1-supply = <&reg11>;
 	vdda1v8-supply = <&reg18>;
 };
+
+&hsem {
+	status = "okay";
+};
-- 
2.15.0

[PATCH 5/5] hwspinlock: Add test module

[Benjamin Gaignard]

Create a test module to perform simple unitary tests on hwspinlock.
It doesn't cover all the possibles cases but at least allow to test
that very basic features are working.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 drivers/hwspinlock/Kconfig           |   9 +++
 drivers/hwspinlock/Makefile          |   1 +
 drivers/hwspinlock/hwspinlock_test.c | 132 +++++++++++++++++++++++++++++++++++
 3 files changed, 142 insertions(+)
 create mode 100644 drivers/hwspinlock/hwspinlock_test.c

diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index e1a20b460590..f340ebb4d1f7 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -68,3 +68,12 @@ config HWSPINLOCK_STM32
 	  Say y here to support the STM32 Hardware Spinlock device.
 
 	  If unsure, say N.
+
+config HWSPINLOCK_TEST
+	tristate "hwspinlock test module"
+	depends on HWSPINLOCK && m
+	default n
+	help
+	  Select M here if you want to build hwspinlock test module
+
+	  If unsure, say N.
diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index c0a9505b4dcf..e6b3d0212fe0 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
 obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
 obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o
+obj-$(CONFIG_HWSPINLOCK_TEST) 		+= hwspinlock_test.o
diff --git a/drivers/hwspinlock/hwspinlock_test.c b/drivers/hwspinlock/hwspinlock_test.c
new file mode 100644
index 000000000000..75819337e45a
--- /dev/null
+++ b/drivers/hwspinlock/hwspinlock_test.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2018
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/hwspinlock.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#define TIMEOUT	50 /* ms */
+
+static void hwspin_lock_test_twice_request_specific(void)
+{
+	struct hwspinlock *lock0 = hwspin_lock_request_specific(0);
+	struct hwspinlock *lock1 = hwspin_lock_request_specific(1);
+
+	int ret;
+
+	if (!lock0 || !lock1) {
+		pr_warn("Can't request twice hwspin_lock\n");
+		return;
+	}
+
+	ret = hwspin_trylock(lock0);
+	if (ret)
+		pr_warn("Can't trylock requested hwspin_lock 0 (%d)\n", ret);
+
+	ret = hwspin_trylock(lock1);
+	if (ret)
+		pr_warn("Can't trylock requested hwspin_lock 1 (%d)\n", ret);
+
+	hwspin_unlock(lock0);
+	hwspin_unlock(lock1);
+
+	ret = hwspin_lock_free(lock0);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+
+	ret = hwspin_lock_free(lock1);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+}
+
+static void hwspin_lock_test_trylock(void)
+{
+	struct hwspinlock *lock = hwspin_lock_request();
+	int ret;
+
+	if (!lock) {
+		pr_warn("Can't request hwspin_lock\n");
+		return;
+	}
+
+	ret = hwspin_trylock(lock);
+	if (ret)
+		pr_warn("Can't trylock requested hwspin_lock (%d)\n", ret);
+
+	/* Try to lock a second time, this should failed */
+	ret = hwspin_trylock(lock);
+	if (ret != -EBUSY)
+		pr_warn("Getting twice the same lock ! (%d)\n", ret);
+
+	hwspin_unlock(lock);
+	ret = hwspin_lock_free(lock);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+}
+
+static void hwspin_lock_test_request_specific(void)
+{
+	/*
+	 * Let's assume that any hwspin_lock driver would at least have one
+	 * lock at index 0
+	 */
+	struct hwspinlock *lock = hwspin_lock_request_specific(0);
+	int ret;
+
+	if (!lock) {
+		pr_warn("Can't request hwspin_lock 0\n");
+		return;
+	}
+
+	ret = hwspin_lock_timeout(lock, TIMEOUT);
+	if (ret)
+		pr_warn("Can't lock requested hwspin_lock 0 (%d)\n", ret);
+
+	hwspin_unlock(lock);
+	ret = hwspin_lock_free(lock);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+}
+
+static void hwspin_lock_test_request(void)
+{
+	struct hwspinlock *lock = hwspin_lock_request();
+	int ret;
+
+	if (!lock) {
+		pr_warn("Can't request hwspin_lock\n");
+		return;
+	}
+
+	ret = hwspin_lock_timeout(lock, TIMEOUT);
+	if (ret)
+		pr_warn("Can't lock requested hwspin_lock (%d)\n", ret);
+
+	hwspin_unlock(lock);
+	ret = hwspin_lock_free(lock);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock\n");
+}
+
+/*
+ * Test hwspinlock user API when module is loaded
+ */
+static int __init hwspin_lock_test_init(void)
+{
+	pr_warn("Loading hwspinlock test module\n");
+	hwspin_lock_test_request();
+	hwspin_lock_test_request_specific();
+	hwspin_lock_test_trylock();
+	hwspin_lock_test_twice_request_specific();
+
+	return 0;
+}
+
+module_init(hwspin_lock_test_init);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Hardware spinlock test driver");
-- 
2.15.0

[PATCH 5/5] hwspinlock: Add test module

[Benjamin Gaignard]

Create a test module to perform simple unitary tests on hwspinlock.
It doesn't cover all the possibles cases but at least allow to test
that very basic features are working.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
---
 drivers/hwspinlock/Kconfig           |   9 +++
 drivers/hwspinlock/Makefile          |   1 +
 drivers/hwspinlock/hwspinlock_test.c | 132 +++++++++++++++++++++++++++++++++++
 3 files changed, 142 insertions(+)
 create mode 100644 drivers/hwspinlock/hwspinlock_test.c

diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index e1a20b460590..f340ebb4d1f7 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -68,3 +68,12 @@ config HWSPINLOCK_STM32
 	  Say y here to support the STM32 Hardware Spinlock device.
 
 	  If unsure, say N.
+
+config HWSPINLOCK_TEST
+	tristate "hwspinlock test module"
+	depends on HWSPINLOCK && m
+	default n
+	help
+	  Select M here if you want to build hwspinlock test module
+
+	  If unsure, say N.
diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index c0a9505b4dcf..e6b3d0212fe0 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
 obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
 obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o
+obj-$(CONFIG_HWSPINLOCK_TEST) 		+= hwspinlock_test.o
diff --git a/drivers/hwspinlock/hwspinlock_test.c b/drivers/hwspinlock/hwspinlock_test.c
new file mode 100644
index 000000000000..75819337e45a
--- /dev/null
+++ b/drivers/hwspinlock/hwspinlock_test.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics SA 2018
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/hwspinlock.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#define TIMEOUT	50 /* ms */
+
+static void hwspin_lock_test_twice_request_specific(void)
+{
+	struct hwspinlock *lock0 = hwspin_lock_request_specific(0);
+	struct hwspinlock *lock1 = hwspin_lock_request_specific(1);
+
+	int ret;
+
+	if (!lock0 || !lock1) {
+		pr_warn("Can't request twice hwspin_lock\n");
+		return;
+	}
+
+	ret = hwspin_trylock(lock0);
+	if (ret)
+		pr_warn("Can't trylock requested hwspin_lock 0 (%d)\n", ret);
+
+	ret = hwspin_trylock(lock1);
+	if (ret)
+		pr_warn("Can't trylock requested hwspin_lock 1 (%d)\n", ret);
+
+	hwspin_unlock(lock0);
+	hwspin_unlock(lock1);
+
+	ret = hwspin_lock_free(lock0);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+
+	ret = hwspin_lock_free(lock1);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+}
+
+static void hwspin_lock_test_trylock(void)
+{
+	struct hwspinlock *lock = hwspin_lock_request();
+	int ret;
+
+	if (!lock) {
+		pr_warn("Can't request hwspin_lock\n");
+		return;
+	}
+
+	ret = hwspin_trylock(lock);
+	if (ret)
+		pr_warn("Can't trylock requested hwspin_lock (%d)\n", ret);
+
+	/* Try to lock a second time, this should failed */
+	ret = hwspin_trylock(lock);
+	if (ret != -EBUSY)
+		pr_warn("Getting twice the same lock ! (%d)\n", ret);
+
+	hwspin_unlock(lock);
+	ret = hwspin_lock_free(lock);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+}
+
+static void hwspin_lock_test_request_specific(void)
+{
+	/*
+	 * Let's assume that any hwspin_lock driver would at least have one
+	 * lock at index 0
+	 */
+	struct hwspinlock *lock = hwspin_lock_request_specific(0);
+	int ret;
+
+	if (!lock) {
+		pr_warn("Can't request hwspin_lock 0\n");
+		return;
+	}
+
+	ret = hwspin_lock_timeout(lock, TIMEOUT);
+	if (ret)
+		pr_warn("Can't lock requested hwspin_lock 0 (%d)\n", ret);
+
+	hwspin_unlock(lock);
+	ret = hwspin_lock_free(lock);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock 0\n");
+}
+
+static void hwspin_lock_test_request(void)
+{
+	struct hwspinlock *lock = hwspin_lock_request();
+	int ret;
+
+	if (!lock) {
+		pr_warn("Can't request hwspin_lock\n");
+		return;
+	}
+
+	ret = hwspin_lock_timeout(lock, TIMEOUT);
+	if (ret)
+		pr_warn("Can't lock requested hwspin_lock (%d)\n", ret);
+
+	hwspin_unlock(lock);
+	ret = hwspin_lock_free(lock);
+	if (ret)
+		pr_warn("Can't free requested hwspin_lock\n");
+}
+
+/*
+ * Test hwspinlock user API when module is loaded
+ */
+static int __init hwspin_lock_test_init(void)
+{
+	pr_warn("Loading hwspinlock test module\n");
+	hwspin_lock_test_request();
+	hwspin_lock_test_request_specific();
+	hwspin_lock_test_trylock();
+	hwspin_lock_test_twice_request_specific();
+
+	return 0;
+}
+
+module_init(hwspin_lock_test_init);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Hardware spinlock test driver");
-- 
2.15.0

Re: [PATCH 2/5] hwspinlock: add STM32 hwspinlock device

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:
> diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
> index e895d29500ee..e1a20b460590 100644
> --- a/drivers/hwspinlock/Kconfig
> +++ b/drivers/hwspinlock/Kconfig
> @@ -59,3 +59,12 @@ config HSEM_U8500
>  	  SoC.
>  
>  	  If unsure, say N.
> +
> +config HWSPINLOCK_STM32

Please keep these alphabetically sorted.

> +	tristate "STM32 Hardware Spinlock device"
> +	depends on MACH_STM32MP157
> +	depends on HWSPINLOCK
> +	help
> +	  Say y here to support the STM32 Hardware Spinlock device.
> +
> +	  If unsure, say N.
> diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
> index b87c01a506a4..c0a9505b4dcf 100644
> --- a/drivers/hwspinlock/Makefile
> +++ b/drivers/hwspinlock/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_HWSPINLOCK_QCOM)		+= qcom_hwspinlock.o
>  obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
>  obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
>  obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
> +obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o

Ditto.

> diff --git a/drivers/hwspinlock/stm32_hwspinlock.c b/drivers/hwspinlock/stm32_hwspinlock.c
> new file mode 100644
> index 000000000000..6a0fafac7389
> --- /dev/null
> +++ b/drivers/hwspinlock/stm32_hwspinlock.c
> @@ -0,0 +1,147 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) STMicroelectronics SA 2018
> + * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
> + * License terms:  GNU General Public License (GPL), version 2

Didn't you already state your license terms with the SPDX header above?

> + */
[..]
> +static int stm32_hwspinlock_remove(struct platform_device *pdev)
> +{
> +	struct stm32_hwspinlock *hw = platform_get_drvdata(pdev);
> +	int ret;
> +
> +	ret = hwspin_lock_unregister(&hw->bank);
> +	if (ret) {
> +		dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
> +		return ret;

The return value of platform_device is ignored, so printing an error
message is fine, but don't "abort".

> +	}
> +
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}

Regards,
Bjorn

[PATCH 2/5] hwspinlock: add STM32 hwspinlock device

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:
> diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
> index e895d29500ee..e1a20b460590 100644
> --- a/drivers/hwspinlock/Kconfig
> +++ b/drivers/hwspinlock/Kconfig
> @@ -59,3 +59,12 @@ config HSEM_U8500
>  	  SoC.
>  
>  	  If unsure, say N.
> +
> +config HWSPINLOCK_STM32

Please keep these alphabetically sorted.

> +	tristate "STM32 Hardware Spinlock device"
> +	depends on MACH_STM32MP157
> +	depends on HWSPINLOCK
> +	help
> +	  Say y here to support the STM32 Hardware Spinlock device.
> +
> +	  If unsure, say N.
> diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
> index b87c01a506a4..c0a9505b4dcf 100644
> --- a/drivers/hwspinlock/Makefile
> +++ b/drivers/hwspinlock/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_HWSPINLOCK_QCOM)		+= qcom_hwspinlock.o
>  obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
>  obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
>  obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
> +obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o

Ditto.

> diff --git a/drivers/hwspinlock/stm32_hwspinlock.c b/drivers/hwspinlock/stm32_hwspinlock.c
> new file mode 100644
> index 000000000000..6a0fafac7389
> --- /dev/null
> +++ b/drivers/hwspinlock/stm32_hwspinlock.c
> @@ -0,0 +1,147 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) STMicroelectronics SA 2018
> + * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
> + * License terms:  GNU General Public License (GPL), version 2

Didn't you already state your license terms with the SPDX header above?

> + */
[..]
> +static int stm32_hwspinlock_remove(struct platform_device *pdev)
> +{
> +	struct stm32_hwspinlock *hw = platform_get_drvdata(pdev);
> +	int ret;
> +
> +	ret = hwspin_lock_unregister(&hw->bank);
> +	if (ret) {
> +		dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
> +		return ret;

The return value of platform_device is ignored, so printing an error
message is fine, but don't "abort".

> +	}
> +
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}

Regards,
Bjorn

Re: [PATCH 1/5] dt-bindings: hwlock: Document STM32 hwspinlock bindings

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:

> Add bindings for STM32 hardware spinlock device
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
> ---
>  .../bindings/hwlock/st,stm32-hwspinlock.txt        | 23 ++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
> 
> diff --git a/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
> new file mode 100644
> index 000000000000..7a999479d802
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
> @@ -0,0 +1,23 @@
> +STM32 Hardware Spinlock Device Binding
> +-------------------------------------
> +
> +Required properties :
> +- compatible : should be "st,stm32-hwspinlock".
> +- reg : the register address of hwspinlock.
> +- #hwlock-cells : hwlock users only use the hwlock id to represent a specific
> +	hwlock, so the number of cells should be <1> here.
> +- clock-names : Must contain "hwspinlock".

This is supposed to be the name of the clock signal of this hardware
block, is it really named "hwspinlock"? Note that you can probably omit
the clock-names property, as you only have a single clock...

Apart from that, I think the binding looks good.

Regards,
Bjorn

> +- clocks : Must contain a phandle entry for the clock in clock-names, see the
> +	common clock bindings.
> +
> +Please look at the generic hwlock binding for usage information for consumers,
> +"Documentation/devicetree/bindings/hwlock/hwlock.txt"
> +
> +Example of hwlock provider:
> +	hwspinlock@4c000000 {
> +		compatible = "st,stm32-hwspinlock";
> +		#hwlock-cells = <1>;
> +		reg = <0x4c000000 0x400>;
> +		clocks = <&rcc HSEM>;
> +		clock-names = "hwspinlock";
> +	};
> -- 
> 2.15.0
> 

[PATCH 1/5] dt-bindings: hwlock: Document STM32 hwspinlock bindings

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:

> Add bindings for STM32 hardware spinlock device
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
> ---
>  .../bindings/hwlock/st,stm32-hwspinlock.txt        | 23 ++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
> 
> diff --git a/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
> new file mode 100644
> index 000000000000..7a999479d802
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwlock/st,stm32-hwspinlock.txt
> @@ -0,0 +1,23 @@
> +STM32 Hardware Spinlock Device Binding
> +-------------------------------------
> +
> +Required properties :
> +- compatible : should be "st,stm32-hwspinlock".
> +- reg : the register address of hwspinlock.
> +- #hwlock-cells : hwlock users only use the hwlock id to represent a specific
> +	hwlock, so the number of cells should be <1> here.
> +- clock-names : Must contain "hwspinlock".

This is supposed to be the name of the clock signal of this hardware
block, is it really named "hwspinlock"? Note that you can probably omit
the clock-names property, as you only have a single clock...

Apart from that, I think the binding looks good.

Regards,
Bjorn

> +- clocks : Must contain a phandle entry for the clock in clock-names, see the
> +	common clock bindings.
> +
> +Please look at the generic hwlock binding for usage information for consumers,
> +"Documentation/devicetree/bindings/hwlock/hwlock.txt"
> +
> +Example of hwlock provider:
> +	hwspinlock at 4c000000 {
> +		compatible = "st,stm32-hwspinlock";
> +		#hwlock-cells = <1>;
> +		reg = <0x4c000000 0x400>;
> +		clocks = <&rcc HSEM>;
> +		clock-names = "hwspinlock";
> +	};
> -- 
> 2.15.0
> 

Re: [PATCH 3/5] ARM: dts: stm32: Add hwspinlock node for stm32mp157 SoC

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:

> Declare hwspinlock device for stm32mp157 SoC
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

Pending the clock-names question,

Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> ---
>  arch/arm/boot/dts/stm32mp157c.dtsi | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/stm32mp157c.dtsi b/arch/arm/boot/dts/stm32mp157c.dtsi
> index 185541a5b69f..9b16c28f8ac3 100644
> --- a/arch/arm/boot/dts/stm32mp157c.dtsi
> +++ b/arch/arm/boot/dts/stm32mp157c.dtsi
> @@ -803,6 +803,15 @@
>  			status = "disabled";
>  		};
>  
> +		hsem: hwspinlock@4c000000 {
> +			compatible = "st,stm32-hwspinlock";
> +			#hwlock-cells = <1>;
> +			reg = <0x4c000000 0x400>;
> +			clocks = <&rcc HSEM>;
> +			clock-names = "hwspinlock";
> +			status = "disabled";
> +		};
> +
>  		rcc: rcc@50000000 {
>  			compatible = "st,stm32mp1-rcc", "syscon";
>  			reg = <0x50000000 0x1000>;
> -- 
> 2.15.0
> 

[PATCH 3/5] ARM: dts: stm32: Add hwspinlock node for stm32mp157 SoC

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:

> Declare hwspinlock device for stm32mp157 SoC
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

Pending the clock-names question,

Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> ---
>  arch/arm/boot/dts/stm32mp157c.dtsi | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/stm32mp157c.dtsi b/arch/arm/boot/dts/stm32mp157c.dtsi
> index 185541a5b69f..9b16c28f8ac3 100644
> --- a/arch/arm/boot/dts/stm32mp157c.dtsi
> +++ b/arch/arm/boot/dts/stm32mp157c.dtsi
> @@ -803,6 +803,15 @@
>  			status = "disabled";
>  		};
>  
> +		hsem: hwspinlock at 4c000000 {
> +			compatible = "st,stm32-hwspinlock";
> +			#hwlock-cells = <1>;
> +			reg = <0x4c000000 0x400>;
> +			clocks = <&rcc HSEM>;
> +			clock-names = "hwspinlock";
> +			status = "disabled";
> +		};
> +
>  		rcc: rcc at 50000000 {
>  			compatible = "st,stm32mp1-rcc", "syscon";
>  			reg = <0x50000000 0x1000>;
> -- 
> 2.15.0
> 

Re: [PATCH 5/5] hwspinlock: Add test module

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:

> Create a test module to perform simple unitary tests on hwspinlock.
> It doesn't cover all the possibles cases but at least allow to test
> that very basic features are working.
> 

I like the idea of making these things testable, but I would like to
hear from others how useful this module would be to them before merging
it.

> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
> ---
>  drivers/hwspinlock/Kconfig           |   9 +++
>  drivers/hwspinlock/Makefile          |   1 +
>  drivers/hwspinlock/hwspinlock_test.c | 132 +++++++++++++++++++++++++++++++++++
>  3 files changed, 142 insertions(+)
>  create mode 100644 drivers/hwspinlock/hwspinlock_test.c
> 
> diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
> index e1a20b460590..f340ebb4d1f7 100644
> --- a/drivers/hwspinlock/Kconfig
> +++ b/drivers/hwspinlock/Kconfig
> @@ -68,3 +68,12 @@ config HWSPINLOCK_STM32
>  	  Say y here to support the STM32 Hardware Spinlock device.
>  
>  	  If unsure, say N.
> +
> +config HWSPINLOCK_TEST
> +	tristate "hwspinlock test module"
> +	depends on HWSPINLOCK && m
> +	default n
> +	help
> +	  Select M here if you want to build hwspinlock test module
> +
> +	  If unsure, say N.
> diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
> index c0a9505b4dcf..e6b3d0212fe0 100644
> --- a/drivers/hwspinlock/Makefile
> +++ b/drivers/hwspinlock/Makefile
> @@ -10,3 +10,4 @@ obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
>  obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
>  obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
>  obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o
> +obj-$(CONFIG_HWSPINLOCK_TEST) 		+= hwspinlock_test.o
> diff --git a/drivers/hwspinlock/hwspinlock_test.c b/drivers/hwspinlock/hwspinlock_test.c
> new file mode 100644
> index 000000000000..75819337e45a
> --- /dev/null
> +++ b/drivers/hwspinlock/hwspinlock_test.c
> @@ -0,0 +1,132 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) STMicroelectronics SA 2018
> + * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
> + * License terms:  GNU General Public License (GPL), version 2
> + */
> +
> +#include <linux/hwspinlock.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +
> +#define TIMEOUT	50 /* ms */
> +
> +static void hwspin_lock_test_twice_request_specific(void)
> +{
> +	struct hwspinlock *lock0 = hwspin_lock_request_specific(0);
> +	struct hwspinlock *lock1 = hwspin_lock_request_specific(1);

In a platform with more than one hwspinlock this will test the
implementation that was first probed and it will assume that there's no
issues with messing with the first two locks from this provider.

> +
> +	int ret;
> +
> +	if (!lock0 || !lock1) {
> +		pr_warn("Can't request twice hwspin_lock\n");
> +		return;
> +	}
> +
> +	ret = hwspin_trylock(lock0);
> +	if (ret)
> +		pr_warn("Can't trylock requested hwspin_lock 0 (%d)\n", ret);
> +
> +	ret = hwspin_trylock(lock1);
> +	if (ret)
> +		pr_warn("Can't trylock requested hwspin_lock 1 (%d)\n", ret);
> +
> +	hwspin_unlock(lock0);
> +	hwspin_unlock(lock1);

As described in the kerneldoc for these it's a bug to attempt to unlock
a unlocked lock. I believe this should be interpreted as it being
invalid to unlock unless hwspin_trylock() returned successfully.

> +
> +	ret = hwspin_lock_free(lock0);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +
> +	ret = hwspin_lock_free(lock1);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +}
> +
> +static void hwspin_lock_test_trylock(void)
> +{
> +	struct hwspinlock *lock = hwspin_lock_request();
> +	int ret;
> +
> +	if (!lock) {
> +		pr_warn("Can't request hwspin_lock\n");
> +		return;
> +	}
> +
> +	ret = hwspin_trylock(lock);
> +	if (ret)
> +		pr_warn("Can't trylock requested hwspin_lock (%d)\n", ret);
> +
> +	/* Try to lock a second time, this should failed */
> +	ret = hwspin_trylock(lock);
> +	if (ret != -EBUSY)
> +		pr_warn("Getting twice the same lock ! (%d)\n", ret);

This shouldn't be a warning, as this is a test failure.

> +
> +	hwspin_unlock(lock);
> +	ret = hwspin_lock_free(lock);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +}
> +
> +static void hwspin_lock_test_request_specific(void)
> +{
> +	/*
> +	 * Let's assume that any hwspin_lock driver would at least have one
> +	 * lock at index 0
> +	 */
> +	struct hwspinlock *lock = hwspin_lock_request_specific(0);
> +	int ret;
> +
> +	if (!lock) {
> +		pr_warn("Can't request hwspin_lock 0\n");
> +		return;
> +	}
> +
> +	ret = hwspin_lock_timeout(lock, TIMEOUT);
> +	if (ret)
> +		pr_warn("Can't lock requested hwspin_lock 0 (%d)\n", ret);
> +
> +	hwspin_unlock(lock);
> +	ret = hwspin_lock_free(lock);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +}
> +
> +static void hwspin_lock_test_request(void)

I would suggest that your test cases test one thing each; so request and
request_specific should test just that.

> +{
> +	struct hwspinlock *lock = hwspin_lock_request();
> +	int ret;
> +
> +	if (!lock) {
> +		pr_warn("Can't request hwspin_lock\n");
> +		return;
> +	}
> +
> +	ret = hwspin_lock_timeout(lock, TIMEOUT);
> +	if (ret)
> +		pr_warn("Can't lock requested hwspin_lock (%d)\n", ret);

Testing lock-timeout seems useful, but you probably want to elaborate it
to ensure that it both can lock a lock but that it times out properly
when trying to grab a taken lock.

> +
> +	hwspin_unlock(lock);
> +	ret = hwspin_lock_free(lock);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock\n");
> +}
> +
> +/*
> + * Test hwspinlock user API when module is loaded
> + */
> +static int __init hwspin_lock_test_init(void)
> +{
> +	pr_warn("Loading hwspinlock test module\n");
> +	hwspin_lock_test_request();
> +	hwspin_lock_test_request_specific();
> +	hwspin_lock_test_trylock();
> +	hwspin_lock_test_twice_request_specific();
> +
> +	return 0;
> +}
> +

Regards,
Bjorn

[PATCH 5/5] hwspinlock: Add test module

[Bjorn Andersson]

On Wed 31 Oct 02:30 PDT 2018, Benjamin Gaignard wrote:

> Create a test module to perform simple unitary tests on hwspinlock.
> It doesn't cover all the possibles cases but at least allow to test
> that very basic features are working.
> 

I like the idea of making these things testable, but I would like to
hear from others how useful this module would be to them before merging
it.

> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
> ---
>  drivers/hwspinlock/Kconfig           |   9 +++
>  drivers/hwspinlock/Makefile          |   1 +
>  drivers/hwspinlock/hwspinlock_test.c | 132 +++++++++++++++++++++++++++++++++++
>  3 files changed, 142 insertions(+)
>  create mode 100644 drivers/hwspinlock/hwspinlock_test.c
> 
> diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
> index e1a20b460590..f340ebb4d1f7 100644
> --- a/drivers/hwspinlock/Kconfig
> +++ b/drivers/hwspinlock/Kconfig
> @@ -68,3 +68,12 @@ config HWSPINLOCK_STM32
>  	  Say y here to support the STM32 Hardware Spinlock device.
>  
>  	  If unsure, say N.
> +
> +config HWSPINLOCK_TEST
> +	tristate "hwspinlock test module"
> +	depends on HWSPINLOCK && m
> +	default n
> +	help
> +	  Select M here if you want to build hwspinlock test module
> +
> +	  If unsure, say N.
> diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
> index c0a9505b4dcf..e6b3d0212fe0 100644
> --- a/drivers/hwspinlock/Makefile
> +++ b/drivers/hwspinlock/Makefile
> @@ -10,3 +10,4 @@ obj-$(CONFIG_HWSPINLOCK_SIRF)		+= sirf_hwspinlock.o
>  obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
>  obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
>  obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o
> +obj-$(CONFIG_HWSPINLOCK_TEST) 		+= hwspinlock_test.o
> diff --git a/drivers/hwspinlock/hwspinlock_test.c b/drivers/hwspinlock/hwspinlock_test.c
> new file mode 100644
> index 000000000000..75819337e45a
> --- /dev/null
> +++ b/drivers/hwspinlock/hwspinlock_test.c
> @@ -0,0 +1,132 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) STMicroelectronics SA 2018
> + * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
> + * License terms:  GNU General Public License (GPL), version 2
> + */
> +
> +#include <linux/hwspinlock.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +
> +#define TIMEOUT	50 /* ms */
> +
> +static void hwspin_lock_test_twice_request_specific(void)
> +{
> +	struct hwspinlock *lock0 = hwspin_lock_request_specific(0);
> +	struct hwspinlock *lock1 = hwspin_lock_request_specific(1);

In a platform with more than one hwspinlock this will test the
implementation that was first probed and it will assume that there's no
issues with messing with the first two locks from this provider.

> +
> +	int ret;
> +
> +	if (!lock0 || !lock1) {
> +		pr_warn("Can't request twice hwspin_lock\n");
> +		return;
> +	}
> +
> +	ret = hwspin_trylock(lock0);
> +	if (ret)
> +		pr_warn("Can't trylock requested hwspin_lock 0 (%d)\n", ret);
> +
> +	ret = hwspin_trylock(lock1);
> +	if (ret)
> +		pr_warn("Can't trylock requested hwspin_lock 1 (%d)\n", ret);
> +
> +	hwspin_unlock(lock0);
> +	hwspin_unlock(lock1);

As described in the kerneldoc for these it's a bug to attempt to unlock
a unlocked lock. I believe this should be interpreted as it being
invalid to unlock unless hwspin_trylock() returned successfully.

> +
> +	ret = hwspin_lock_free(lock0);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +
> +	ret = hwspin_lock_free(lock1);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +}
> +
> +static void hwspin_lock_test_trylock(void)
> +{
> +	struct hwspinlock *lock = hwspin_lock_request();
> +	int ret;
> +
> +	if (!lock) {
> +		pr_warn("Can't request hwspin_lock\n");
> +		return;
> +	}
> +
> +	ret = hwspin_trylock(lock);
> +	if (ret)
> +		pr_warn("Can't trylock requested hwspin_lock (%d)\n", ret);
> +
> +	/* Try to lock a second time, this should failed */
> +	ret = hwspin_trylock(lock);
> +	if (ret != -EBUSY)
> +		pr_warn("Getting twice the same lock ! (%d)\n", ret);

This shouldn't be a warning, as this is a test failure.

> +
> +	hwspin_unlock(lock);
> +	ret = hwspin_lock_free(lock);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +}
> +
> +static void hwspin_lock_test_request_specific(void)
> +{
> +	/*
> +	 * Let's assume that any hwspin_lock driver would at least have one
> +	 * lock at index 0
> +	 */
> +	struct hwspinlock *lock = hwspin_lock_request_specific(0);
> +	int ret;
> +
> +	if (!lock) {
> +		pr_warn("Can't request hwspin_lock 0\n");
> +		return;
> +	}
> +
> +	ret = hwspin_lock_timeout(lock, TIMEOUT);
> +	if (ret)
> +		pr_warn("Can't lock requested hwspin_lock 0 (%d)\n", ret);
> +
> +	hwspin_unlock(lock);
> +	ret = hwspin_lock_free(lock);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock 0\n");
> +}
> +
> +static void hwspin_lock_test_request(void)

I would suggest that your test cases test one thing each; so request and
request_specific should test just that.

> +{
> +	struct hwspinlock *lock = hwspin_lock_request();
> +	int ret;
> +
> +	if (!lock) {
> +		pr_warn("Can't request hwspin_lock\n");
> +		return;
> +	}
> +
> +	ret = hwspin_lock_timeout(lock, TIMEOUT);
> +	if (ret)
> +		pr_warn("Can't lock requested hwspin_lock (%d)\n", ret);

Testing lock-timeout seems useful, but you probably want to elaborate it
to ensure that it both can lock a lock but that it times out properly
when trying to grab a taken lock.

> +
> +	hwspin_unlock(lock);
> +	ret = hwspin_lock_free(lock);
> +	if (ret)
> +		pr_warn("Can't free requested hwspin_lock\n");
> +}
> +
> +/*
> + * Test hwspinlock user API when module is loaded
> + */
> +static int __init hwspin_lock_test_init(void)
> +{
> +	pr_warn("Loading hwspinlock test module\n");
> +	hwspin_lock_test_request();
> +	hwspin_lock_test_request_specific();
> +	hwspin_lock_test_trylock();
> +	hwspin_lock_test_twice_request_specific();
> +
> +	return 0;
> +}
> +

Regards,
Bjorn